WorldWideScience

Sample records for climate control factors

  1. Climate Controlled?

    Science.gov (United States)

    Harney, John O.

    2014-01-01

    More than 250 higher education leaders from campuses across the U.S. met last week in Boston for the 2014 Presidential Summit on Climate Leadership. The summit was organized by Second Nature, the supporting organization for the American College & University Presidents' Climate Commitment (ACUPCC). Almost 700 colleges and universities have…

  2. Depression, Control, and Climate: An Examination of Factors Impacting Teaching Quality in Preschool Classrooms

    Science.gov (United States)

    Sandilos, Lia E.; Cycyk, Lauren M.; Scheffner Hammer, Carol; Sawyer, Brook E.; López, Lisa; Blair, Clancy

    2015-01-01

    Research Findings: This study investigated the relationship of preschool teachers' self-reported depressive symptomatology, perception of classroom control, and perception of school climate to classroom quality as measured by the Classroom Assessment Scoring System Pre-K. The sample consisted of 59 urban preschool classrooms serving low-income and…

  3. Dengue vector dynamics (Aedes aegypti influenced by climate and social factors in Ecuador: implications for targeted control.

    Directory of Open Access Journals (Sweden)

    Anna M Stewart Ibarra

    Full Text Available BACKGROUND: Dengue fever, a mosquito-borne viral disease, is now the fastest spreading tropical disease globally. Previous studies indicate that climate and human behavior interact to influence dengue virus and vector (Aedes aegypti population dynamics; however, the relative effects of these variables depends on local ecology and social context. We investigated the roles of climate and socio-ecological factors on Ae. aegypti population dynamics in Machala, a city in southern coastal Ecuador where dengue is hyper-endemic. METHODS/PRINCIPAL FINDINGS: We studied two proximate urban localities where we monitored weekly Ae. aegypti oviposition activity (Nov. 2010-June 2011, conducted seasonal pupal surveys, and surveyed household to identify dengue risk factors. The results of this study provide evidence that Ae. aegypti population dynamics are influenced by social risk factors that vary by season and lagged climate variables that vary by locality. Best-fit models to predict the presence of Ae. aegypti pupae included parameters for household water storage practices, access to piped water, the number of households per property, condition of the house and patio, and knowledge and perceptions of dengue. Rainfall and minimum temperature were significant predictors of oviposition activity, although the effect of rainfall varied by locality due to differences in types of water storage containers. CONCLUSIONS: These results indicate the potential to reduce the burden of dengue in this region by conducting focused vector control interventions that target high-risk households and containers in each season and by developing predictive models using climate and non-climate information. These findings provide the region's public health sector with key information for conducting time and location-specific vector control campaigns, and highlight the importance of local socio-ecological studies to understand dengue dynamics. See Text S1 for an executive summary in

  4. Dengue Vector Dynamics (Aedes aegypti) Influenced by Climate and Social Factors in Ecuador: Implications for Targeted Control

    Science.gov (United States)

    Stewart Ibarra, Anna M.; Ryan, Sadie J.; Beltrán, Efrain; Mejía, Raúl; Silva, Mercy; Muñoz, Ángel

    2013-01-01

    Background Dengue fever, a mosquito-borne viral disease, is now the fastest spreading tropical disease globally. Previous studies indicate that climate and human behavior interact to influence dengue virus and vector (Aedes aegypti) population dynamics; however, the relative effects of these variables depends on local ecology and social context. We investigated the roles of climate and socio-ecological factors on Ae. aegypti population dynamics in Machala, a city in southern coastal Ecuador where dengue is hyper-endemic. Methods/Principal findings We studied two proximate urban localities where we monitored weekly Ae. aegypti oviposition activity (Nov. 2010-June 2011), conducted seasonal pupal surveys, and surveyed household to identify dengue risk factors. The results of this study provide evidence that Ae. aegypti population dynamics are influenced by social risk factors that vary by season and lagged climate variables that vary by locality. Best-fit models to predict the presence of Ae. aegypti pupae included parameters for household water storage practices, access to piped water, the number of households per property, condition of the house and patio, and knowledge and perceptions of dengue. Rainfall and minimum temperature were significant predictors of oviposition activity, although the effect of rainfall varied by locality due to differences in types of water storage containers. Conclusions These results indicate the potential to reduce the burden of dengue in this region by conducting focused vector control interventions that target high-risk households and containers in each season and by developing predictive models using climate and non-climate information. These findings provide the region's public health sector with key information for conducting time and location-specific vector control campaigns, and highlight the importance of local socio-ecological studies to understand dengue dynamics. See Text S1 for an executive summary in Spanish. PMID:24324542

  5. Smarter greenhouse climate control

    NARCIS (Netherlands)

    Nederhoff, E.M.; Houter, G.

    2011-01-01

    Greenhouse operators strive to be as economic as possible with energy. However, investing in fancy energy-saving equipment is often not cost-effective for smaller operations and in climate zones with mild winters. It is possible, though, for many growers to save energy without buying special equipme

  6. Assessing morphological, climatic and structural factors controlling water discharge and sediment load of rivers flowing from the Sierra Madre de Chiapas to the Pacific Coast (Southern Mexico)

    Science.gov (United States)

    Munoz-Salinas, E.; Castillo, M.

    2014-12-01

    The Sierra Madre de Chiapas (SMC) is a steep mountain range located in the south-western part of Mexico with elevations higher than 2000 m. The SMC is ~30 km off the Pacific Coast and it is oriented parallel to the coast. The annual rainfall exceeds 6 m and most of this takes place during summer season when low-pressure systems and cyclones are frequent. The rivers in SMC incise into the granite and transport large volumes of sediment. Even though rivers can be regarded as bedrock bedrock channels these suddenly change to alluvial-type rivers when these flow in the coastal plain which is ~10 km from the headwater of rivers. There are not data available of the sediment yield of rivers, however, the well-broad coastal plain and the wide continental shelf suggest that the sediment transport from the mountain area to the lowlands is significantly high. Here we assess the main morphological, climatic and structural factors controlling water discharge and sediment load of the rivers flowing from the SMC to the Pacific Coast by means of (1) topographical analysis on a high-resolution DEM, (2) grain-size and OSL analysis on sediment extracted from the riverbed of the main rivers and (3) time-series analysis from the available data of sediment discharge and sediment load. Our results indicate that the river incision and sediment transport is particularly high at the southern sector of the SMC where the topographic and climatic factors promote higher erosion rates.

  7. Thresholds controlling shifts in forest cover types in the boreal region of Interior Alaska: inter- actions between climate, fire and edaphic factors

    Science.gov (United States)

    Kasischke, E. S.; Johnstone, J. F.; Rupp, S.; Duffy, P. A.; Kielland, K.; Chapin, F. S.

    2007-12-01

    There is a general consensus that future warming in the North American Boreal Region will cause a reduction in coniferous species common to cool, wet sites and an increase in deciduous/coniferous species found on warmer drier sites. In addition, it is believed that much of the change in forest cover will occur during secondary succession following disturbance and that the frequency of disturbance is likely to increase in response to climate warming; however, neither the rate at forest cover will change, nor the mechanisms thereof are well understood. Here, we summarize results from recent studies in Alaska that are being carried out as part of the Bonanza Creek Long Term Ecological Research Project and research being funded by the Joint Fire Science Program and NASA. We have examined factors important in regulating the change in the extent of black spruce (Picea mariana), a dominant forest type across the North American boreal region. Depth of burning of the surface organic layer is a fire severity measure that is important in regulating the post-fire environment in black spruce forests. In particular, seeds from deciduous trees have extremely low germination rates in post-fire organic soils that are greater than 3 cm deep. In addition, we found the growth of deciduous species in burned stands is inversely proportional to the depth of the remaining organic soil, with the highest growth observed on sites with exposed mineral soils. Other factors controlling seedling survival and growth include soil temperature and moisture, nutrient availability, and the fact that deciduous and coniferous species have different capabilities in absorbing different forms of soil nitrogen. These additional factors are also controlled by the amount of organic soil remaining after the fire. Finally, our research has shown that the depth of the remaining organic soil after fires is controlled both by topography and climate, with the frequency of sites with organic layers shallower than 3

  8. Climate modification directed by control theory

    CERN Document Server

    Liang, Wang

    2008-01-01

    Climate modification measures to counteract global warming receive some more new attentions in these years. Most current researches only discuss the impact of these measures to climate, but how to design such a climate regulator is still unknown. This paper shows the control theory could give the systematic direction for climate modification. But the control analyzing also reveals that climate modifications should only be regarded as a last-ditch measure.

  9. SCHOOL CLIMATE AND TEACHERS’ PERCEPTIONS ON CLIMATE FACTORS:

    Directory of Open Access Journals (Sweden)

    İlhan GÜNBAYI

    2006-12-01

    Full Text Available This study examined the difference in the levels of the variables related to the schoolclimate factors among the teachers teaching social science courses, the teachers teaching natural science courses,and the teachers teaching art, music and physical education. The data collected from a sample of 204 teachersfrom 9 urban schools serving general high school education in the centre of Afyon and Usak cities in Turkey bymeans of the questionnaire developed by the researcher in the academic year of 2001-2002. The questionnaireasked the participants to report the perceived school climate levels of the variables related to the organizationalclimate factors - organizational clarity and standards, team commitment, autonomy, intimacy and support,member conflict, rewards, and risk - on the open-to-closed continuum. The data collected were analyzed by t-testfor Equality of Means and Analysis of Variance and Tukey post hoc tests. As a result of the analyzes, all theteachers reported open climate in relation to the factors of team commitment, organizational clarity andstandards, intimacy and support , autonomy, member conflict, medium climate in relation to the factors of riskand in reward. Additionally, the teachers teaching art, music and physical education reported higher open schoolclimate than others, man than women, single teachers than married ones, the teachers with more degree ofeducation than the ones with a lower degree of education, older teachers than younger ones, and the teacherswith less seniority than the ones with more seniority. Finally, some ideas were suggested about what should bedone in helping teachers to work in a more desirable open school climate

  10. CLIMATE AS A RISK FACTOR FOR TOURISM

    Directory of Open Access Journals (Sweden)

    ÁKOS NÉMETH

    2009-12-01

    Full Text Available Weather and climate risk factors for tourism are surveyed and illustrated with regard to the expected climate changes in Hungary. These changes are not at all advantageous and which affect the business in question both directly and indirectly. These are the summer resort tourism (characterised by bioclimatic indices. Green tourism is the next one to characterise, including skiing, mountain climbing and eco-tourism, as well. Here both day-to-day weather extremes and long-lasting effects on the biota (e.g. drought, or inundation for plain-area eco-tourism. Last, but not least the urban (cultural- and shopping- tourism is presented, since the large towns exhibit their special climate and different risks. The paper intends to specify these meteorological factors and effects also in terms of the different types of touristic activities. The general statements on the effect of weather and climate on tourism are illustrated by a few individual parameters and also by the so called Physiologically Equivalent Temperature. Annual and diurnal course of this parameter are presented, together with various trends in this variable at different sites and in different (hot and cold extremities of the occurring values. Other examples, helping the tourism industry are presented in various climate conditions of the country. They include high precipitation and high relative humidity information. The paper also lists the possible adaptation measures to extreme events and also their likely changes in time.

  11. Determinants of palm species distributions across Africa: the relative roles of climate, non-climatic environmental factors, and spatial constraints

    DEFF Research Database (Denmark)

    Overgaard, Anne Blach; Svenning, J.-C.; Dransfield, John;

    2010-01-01

    ' ranges may be controlled by soil or other environmental factors, or by non-environmental factors such as biotic interactions, dispersal barriers, intrinsic population dynamics, or time-limited expansion from place of origin or past refugia. How species ranges are controlled is of key importance......-climatic environmental factors, or non-environmental spatial constraints. A comprehensive data set on African palm species occurrences was assembled and analysed using the SDM algorithm Maxent in combination with climatic and non-climatic environmental predictors (habitat, human impact), as well as spatial eigenvector...

  12. Greenhouse climate management: an optimal control approach.

    NARCIS (Netherlands)

    Henten, van E.J.

    1994-01-01

    In this thesis a methodology is developed for the construction and analysis of an optimal greenhouse climate control system.In chapter 1, the results of a literature survey are presented and the research objectives are defined. In the literature, optimal greenhouse climate management systems have be

  13. Palaeogeographic controls on climate and proxy interpretation

    Science.gov (United States)

    Lunt, Daniel J.; Farnsworth, Alex; Loptson, Claire; Foster, Gavin L.; Markwick, Paul; O'Brien, Charlotte L.; Pancost, Richard D.; Robinson, Stuart A.; Wrobel, Neil

    2016-05-01

    During the period from approximately 150 to 35 million years ago, the Cretaceous-Paleocene-Eocene (CPE), the Earth was in a "greenhouse" state with little or no ice at either pole. It was also a period of considerable global change, from the warmest periods of the mid-Cretaceous, to the threshold of icehouse conditions at the end of the Eocene. However, the relative contribution of palaeogeographic change, solar change, and carbon cycle change to these climatic variations is unknown. Here, making use of recent advances in computing power, and a set of unique palaeogeographic maps, we carry out an ensemble of 19 General Circulation Model simulations covering this period, one simulation per stratigraphic stage. By maintaining atmospheric CO2 concentration constant across the simulations, we are able to identify the contribution from palaeogeographic and solar forcing to global change across the CPE, and explore the underlying mechanisms. We find that global mean surface temperature is remarkably constant across the simulations, resulting from a cancellation of opposing trends from solar and palaeogeographic change. However, there are significant modelled variations on a regional scale. The stratigraphic stage-stage transitions which exhibit greatest climatic change are associated with transitions in the mode of ocean circulation, themselves often associated with changes in ocean gateways, and amplified by feedbacks related to emissivity and planetary albedo. We also find some control on global mean temperature from continental area and global mean orography. Our results have important implications for the interpretation of single-site palaeo proxy records. In particular, our results allow the non-CO2 (i.e. palaeogeographic and solar constant) components of proxy records to be removed, leaving a more global component associated with carbon cycle change. This "adjustment factor" is used to adjust sea surface temperatures, as the deep ocean is not fully equilibrated in

  14. The human factor: climate change and climate communication

    DEFF Research Database (Denmark)

    2011-01-01

    Reprint and translation of the article: “Den menneskelige faktor” published in the magazine Klima&Tilpasning Publisher: “Coordination unit for Research in Climate Change Adaptation” (KFT)......Reprint and translation of the article: “Den menneskelige faktor” published in the magazine Klima&Tilpasning Publisher: “Coordination unit for Research in Climate Change Adaptation” (KFT)...

  15. Climate Control Using Nuclear Energy

    CERN Document Server

    Modgil, Moninder Singh

    2008-01-01

    We examine implications of anthropogenic low pressure regions, - created by injecting heat from nuclear reactors, into atmosphere. We suggest the possibility that such artificially generated low pressure regions, near hurricanes could disrupt their growth, path, and intensity. This method can also create controlled tropical stroms, which lead to substantial rainfall in arid areas, such as - (1)Sahara desert, (2) Australian interior desert, and (3) Indian Thar desert. A simple vortex suction model is developed to study, effect on atmospheric dynamics, by such a nuclear heat injection system.

  16. Variable temperature seat climate control system

    Science.gov (United States)

    Karunasiri, Tissa R.; Gallup, David F.; Noles, David R.; Gregory, Christian T.

    1997-05-06

    A temperature climate control system comprises a variable temperature seat, at least one heat pump, at least one heat pump temperature sensor, and a controller. Each heat pump comprises a number of Peltier thermoelectric modules for temperature conditioning the air in a main heat exchanger and a main exchanger fan for passing the conditioned air from the main exchanger to the variable temperature seat. The Peltier modules and each main fan may be manually adjusted via a control switch or a control signal. Additionally, the temperature climate control system may comprise a number of additional temperature sensors to monitor the temperature of the ambient air surrounding the occupant as well as the temperature of the conditioned air directed to the occupant. The controller is configured to automatically regulate the operation of the Peltier modules and/or each main fan according to a temperature climate control logic designed both to maximize occupant comfort during normal operation, and minimize possible equipment damage, occupant discomfort, or occupant injury in the event of a heat pump malfunction.

  17. Climate Change and the Social Factor

    DEFF Research Database (Denmark)

    Petersen, Lars Kjerulf; Jensen, Anne; Nielsen, Signe Svalgaard

    risks and concerns of everyday life? The project found that the distinction between climate change mitigation and adaptation is of little significance for lay people. The prospect of climate change does provoke reflections on social values and the need for saving energy, but when it comes to protecting......This poster reports from a explorative study about social aspects of climate change adaptation in Denmark. The aim of the project was to explore how people perceive and relate to climate change adaptation, what risks are associated with climate change and how are those risks balanced with other...... ones own life and property against future damaging effects of climate change the threat seems distant and other forms of home improvement seem more relevant. People have a high level of trust in socio-technical systems and feel that adaptation measures primarily should be taken by the authorities....

  18. System Identification for Indoor Climate Control

    CERN Document Server

    M., A W; H., P W M; Steskens,

    2012-01-01

    The study focuses on the applicability of system identification to identify building and system dynamics for climate control design. The main problem regarding the simulation of the dynamic response of a building using building simulation software is that (1) the simulation of a large complex building is time consuming, and (2) simulation results often lack information regarding fast dynamic behaviour (in the order of seconds), since most software uses a discrete time step, usually fixed to one hour. The first objective is to study the applicability of system identification to reduce computing time for the simulation of large complex buildings. The second objective is to research the applicability of system identification to identify building dynamics based on discrete time data (one hour) for climate control design. The study illustrates that system identification is applicable for the identification of building dynamics with a frequency that is smaller as the maximum sample frequency as used for identificat...

  19. Multi-factor climate change effects on insect herbivore performance

    DEFF Research Database (Denmark)

    Scherber, Christoph; Gladbach, David J; Stevnbak, Karen;

    2013-01-01

    The impact of climate change on herbivorous insects can have far-reaching consequences for ecosystem processes. However, experiments investigating the combined effects of multiple climate change drivers on herbivorous insects are scarce. We independently manipulated three climate change drivers (CO......, nitrogen, and water content. Overall, drought was the most important factor for this insect herbivore. Our study shows that weight and survival of insect herbivores may decline under future climate. The complexity of insect herbivore responses increases with the number of combined climate change drivers....

  20. Factors associated with asthma control.

    NARCIS (Netherlands)

    Vries, M.P. de; Bemt, E.A.J.M. van den; Lince, S.; Muris, J.W.M.; Thoonen, B.P.A.; Schayck, C.P. van

    2005-01-01

    The aim of this study was to evaluate which factors are associated with asthma control experienced by asthma patients. In a cross-sectional study patients aged 16-60 years with mild to moderate asthma were selected. The influence of the following factors on asthma control was studied in a multivaria

  1. Spatiotemporal distribution of malaria and the association between its epidemic and climate factors in Hainan, China

    OpenAIRE

    Li Lang; Wang Guangze; Xu Dezhong; Fang Liqun; Wang Shanqing; Long Yong; Xiao Dan; Cao Wuchun; Yan Yongping

    2010-01-01

    Abstract Background Hainan is one of the provinces most severely affected by malaria epidemics in China. The distribution pattern and major determinant climate factors of malaria in this region have remained obscure, making it difficult to target countermeasures for malaria surveillance and control. This study detected the spatiotemporal distribution of malaria and explored the association between malaria epidemics and climate factors in Hainan. Methods The cumulative and annual malaria incid...

  2. Correlation of climatic factors and dengue incidence in Metro Manila, Philippines.

    Science.gov (United States)

    Su, Glenn L Sia

    2008-06-01

    Dengue is a serious public health problem in Metro Manila, Philippines. Increasing dengue incidence has been attributed to climate change; however, contradicting reports show inconclusive relationships between dengue and climatic factors. This study investigates temperature and rainfall as climatic factors affecting dengue incidence in Metro Manila from 1996 to 2005. Monthly dengue incidence and climatic data for Metro Manila were collected over a 10-y period (1996-2005). Climatic factors temperature and rainfall were linked with dengue incidence through regression analysis. A predictive model equation plots dengue incidence (Y) versus rainfall (X), which suggests that rainfall is significantly correlated to dengue incidence (r2 = 0.377, p 0.05). Evidence shows dengue incidence in Metro Manila varies with changing rainfall patterns. Intensified surveillance and control of mosquitoes during periods with high rainfall are recommended.

  3. Climate change - clouds remain the misty factor

    NARCIS (Netherlands)

    Muller, M.

    2007-01-01

    Clouds are the great unknown quantity in predictions about climate change. For aeons they have been drifting quietly across the sky, but scientists still dont know exactly how they are formed and why they eventually come down again as rain. High time to take a closer look at clouds, say researchers

  4. Identification and Resolution of Feature Interactions in Greenhouse Climate Control

    DEFF Research Database (Denmark)

    Sørensen, Jan Corfixen

    another causing unexpected or undesirable climate control outputs. Malfunctioning behavior as a consequence of control strategy interference is know in the literature as the feature interaction problem. This PhD dissertation presents a feature interaction manager (FIM) that uses an evolutionary search......The slow adoption pace of new control strategies for sustainable greenhouse climate control by industrial growers, is mainly due to the complexity of identifying and resolving potentially conflicting climate control requirements. When separate climate control strategies are composed they become...... coupled through the shared environment resources. As a consequence, the greenhouse climate control system requirements may no longer be entailed when independent climate control strategies try to control the same shared environment phenomena. The problem emerges when control strategies interfere with one...

  5. Thermal battery for portable climate control

    International Nuclear Information System (INIS)

    Highlights: • ATB is adsorptive thermal battery delivering both heating and cooling via storage. • The novel design promotes transport and maximizes ATB performance. • A general theoretical framework is developed to analyze ATB performance. • NaX–water is used as the adsorbent–refrigerant pair as a specific case study. • The effect of key geometric parameters and operating conditions are presented. - Abstract: Current technologies that provide climate control in the transportation sector are quite inefficient. In gasoline-powered vehicles, the use of air-conditioning is known to result in higher emissions of greenhouse gases and pollutants apart from decreasing the gas-mileage. On the other hand, for electric vehicles (EVs), a drain in the onboard electric battery due to the operation of heating and cooling system results in a substantial decrease in the driving range. As an alternative to the conventional climate control system, we are developing an adsorption-based thermal battery (ATB), which is capable of storing thermal energy, and delivering both heating and cooling on demand, while requiring minimal electric power supply. Analogous to an electrical battery, the ATB can be charged for reuse. Furthermore, it promises to be compact, lightweight, and deliver high performance, which is desirable for mobile applications. In this study, we describe the design and operation of the ATB-based climate control system. We present a general theoretical framework to determine the maximum achievable heating and cooling performance using the ATB. The framework is then applied to study the feasibility of ATB integration in EVs, wherein we analyze the use of NaX zeolite–water as the adsorbent–refrigerant pair. In order to deliver the necessary heating and cooling performance, exceeding 2.5 kW h thermal capacity for EVs, the analysis determines the optimal design and operating conditions. While the use of the ATB in EVs can potentially enhance its driving

  6. Multi-factor climate change effects on insect herbivore performance

    DEFF Research Database (Denmark)

    Scherber, Christoph; Gladbach, David J; Stevnbak, Karen;

    2013-01-01

    The impact of climate change on herbivorous insects can have far-reaching consequences for ecosystem processes. However, experiments investigating the combined effects of multiple climate change drivers on herbivorous insects are scarce. We independently manipulated three climate change drivers (CO...... the drought treatment, and there was a three-way interaction between time, CO2, and drought. Survival was lowest when drought, warming, and elevated CO2 were combined. Effects of climate change drivers depended on other co-acting factors and were mediated by changes in plant secondary compounds, nitrogen...... suturalis Thomson), an important herbivore on heather, to ambient versus elevated drought, temperature, and CO2 (plus all combinations) for 5 weeks. Larval weight and survival were highest under ambient conditions and decreased significantly with the number of climate change drivers. Weight was lowest under...

  7. Assessment of factors responsbile for climate change and human health problems

    Science.gov (United States)

    Jena, V. K.

    2010-09-01

    Weather and climate play important roles in determining patterns of air quality over multiple scales in time and space. Air quality is strongly dependent on weather and is therefore sensitive to climate change. There is growing recognition that development of optimal control strategies for key pollutants like fine particles now requires assessment of potential future climate conditions and their influence on the attainment of air quality objectives. Climate change induced by anthropogenic warming of the earth's atmosphere is a daunting problem. In addition, other air contaminants of relevance to human health, including smoke from wildfires and airborne pollens and molds, may be influenced by climate change. While further research is needed, climate change coupled with air pollutant exposures may have potentially serious adverse consequences for human health in urban and polluted regions. Climate change producing alterations in: food webs, lipid dynamics, ice and snow melt, and organic carbon cycling could result in increased PMs level in air. In this study, the focus is on the ways in which health-relevant measures of air quality, including particulate matter, and aeroallergens, may be affected by climate variability and change. The small but growing literature focusing on climate impacts on air quality, how these influences may play out in future decades, and the implications for human health is reviewed. Keywords: Climate change, responsible factors, health effects,

  8. Climatic factors influencing triatomine occurrence in Central-West Brazil

    OpenAIRE

    Joyce Mendes Pereira; Paulo Silva de Almeida; Adair Vieira de Sousa; Aécio Moraes de Paula; Ricardo Bomfim Machado; Rodrigo Gurgel-Gonçalves

    2013-01-01

    We estimated the geographic distributions of triatomine species in Central-West Region of Brazil (CW) and analysed the climatic factors influencing their occurrence. A total of 3,396 records of 27 triatomine species were analysed. Using the maximum entropy method, ecological niche models were produced for eight species occurring in at least 20 municipalities based on 13 climatic variables and elevation. Triatoma sordida and Rhodnius neglectus were the species with the broadest geographic dist...

  9. Branch and Bound algorithms in greenhouse climate control

    OpenAIRE

    Hermelink, Marleen

    2016-01-01

    The horticultural sector has become an increasingly important sector of food production, for which greenhouse climate control plays a vital role in improving its sustainability. One of the methods to control the greenhouse climate is Model Predictive Control, which can be optimized through a branch and bound algorithm. The application of the algorithm in literature is examined and analyzed through small examples, and later extended to greenhouse climate simulation. A comparison is ma...

  10. Palaeogeographic controls on climate and proxy interpretation

    Directory of Open Access Journals (Sweden)

    D. J. Lunt

    2015-12-01

    Full Text Available During the period from approximately 150 to 35 million years ago, the Cretaceous–Paleocene–Eocene (CPE, the Earth was in a "greenhouse" state with little or no ice at either pole. It was also a period of considerable global change, from the warmest periods of the mid Cretaceous, to the threshold of icehouse conditions at the end of the Eocene. However, the relative contribution of palaeogeographic change, solar change, and carbon cycle change to these climatic variations is unknown. Here, making use of recent advances in computing power, and a set of unique palaeogeographic maps, we carry out an ensemble of 19 General Circulation Model simulations covering this period, one simulation per stratigraphic stage. By maintaining atmospheric CO2 concentration constant across the simulations, we are able to identify the contribution from palaeogeographic and solar forcing to global change across the CPE, and explore the underlying mechanisms. We find that global mean surface temperature is remarkably constant across the simulations, resulting from a cancellation of opposing trends from solar and paleogeographic change. However, there are significant modelled variations on a regional scale. The stratigraphic stage–stage transitions which exhibit greatest climatic change are associated with transitions in the mode of ocean circulation, themselves often associated with changes in ocean gateways, and amplified by feedbacks related to emissivity and albedo. Our results also have implications for the interpretation of single-site palaeo proxy records. In particular, our results allow the non-CO2 (i.e. palaeogeographic and solar constant components of proxy records to be removed, leaving a more global component associated with carbon cycle change. This "adjustment factor" is illustrated for 7 key sites in the CPE, and applied to proxy data from Falkland Plateau, and we provide data so that similar adjustments can be made to any site and for any time

  11. Climatic controls on diffuse groundwater recharge across Australia

    Directory of Open Access Journals (Sweden)

    O. V. Barron

    2012-05-01

    Full Text Available Reviews of field studies of groundwater recharge have attempted to investigate how climate characteristics control recharge, but due to a lack of data have not been able to draw any strong conclusions beyond that rainfall is the major determinant. This study has used numerical modeling for a range of Köppen-Geiger climate types (tropical, arid and temperate to investigate the effect of climate variables on recharge for different soil and vegetation types. For the majority of climate types the total annual rainfall had a weaker correlation with recharge than the rainfall parameters reflecting rainfall intensity. In regions with winter-dominated rainfall, annual recharge under the same annual rainfall, soils and vegetation conditions is greater than in regions with summer-dominated rainfall. The relative importance of climate parameters other than rainfall is higher for recharge under annual vegetation, but overall is highest in the tropical climate type. Solar radiation and vapour pressure deficit show a greater relative importance than mean annual daily mean temperature. Climate parameters have lowest relative importance in the arid climate type (with cold winters and the temperate climate type. For 75% of all considered cases of soil, vegetation and climate types recharge elasticity varies between 2 and 4, indicating a 20% to 40% change in recharge for a 10% change in annual rainfall Understanding how climate controls recharge under the observed historical climate allows more informed choices of analogue sites if they are to be used for climate change impact assessments.

  12. Revisiting factors controlling methane emissions from high-Arctic tundra

    DEFF Research Database (Denmark)

    Mastepanov, M.; Sigsgaard, Charlotte; Tagesson, Håkan Torbern;

    2013-01-01

    controlling methane emission, i.e. temperature and water table position. Late in the growing season CH4 emissions were found to be very similar between the study years (except the extremely dry 2010) despite large differences in climatic factors (temperature and water table). Late-season bursts of CH4...... short-term control factors (temperature and water table). Our findings suggest the importance of multiyear studies with a continued focus on shoulder seasons in Arctic ecosystems....

  13. Model based design of optimal multivariable climate control systems.

    NARCIS (Netherlands)

    Henten, van E.J.

    1989-01-01

    The simulation results are presented of the application of the linear quadratic performance (LQP) control design methodology to a non-linear physical greenhouse climate system. A multivariable greenhouse climate model designed by Bot (1983) is used for controller design and evaluation. First, the no

  14. Solar Powered Automobile Interior Climate Control System

    Science.gov (United States)

    Howard, Richard T. (Inventor)

    2003-01-01

    There is provided a climate control system for a parked vehicle that includes a solar panel, thermostatic switch, fans, and thermoelectric coolers. The solar panel can serve as the sole source of electricity for the system. The system affords convenient installation and removal by including solar panels that are removably attached to the exterior of a vehicle. A connecting wire electrically connects the solar panels to a housing that is removably mounted to a partially opened window on the vehicle. The thermostatic switch, fans, and thermoelectric coolers are included within the housing. The thermostatic switch alternates the direction of the current flow through the thermoelectric coolers to selectively heat or cool the interior of the vehicle. The interior surface of the thermoelectric coolers are in contact with interior heat sinks that have air circulated across them by an interior fan. Similarly, the exterior surface of the thermoelectric coolers are in contact with exterior heat sinks that have air circulated across them by an exterior fan.

  15. INFLUENCE OF CLIMATIC FACTOR ON SPECIFIC CONSUMPTION OF GRAPHITIZED ELECTRODES

    Directory of Open Access Journals (Sweden)

    O. M. Grudnitskiy

    2012-01-01

    Full Text Available It is shown that influence of climatic factor on production processes is necessary to be taken into account at planning of enterprise work: to carry out correction of production schedules, and also to vary specific norms of raw and materials consumption.

  16. Global warming and climate change: control methods

    International Nuclear Information System (INIS)

    This paper aimed at finding causes of global warming and ways to bring it under control. Data based on scientific opinion as given by synthesis reports of news, articles, web sites, and books. global warming is the observed and projected increases in average temperature of Earth's atmosphere and oceans. Carbon dioxide and other air pollution that is collecting in the atmosphere like a thickening blanket, trapping the sun's heat and causing the planet to warm up. Pollution is one of the biggest man-made problems. Burning fossil fuels is the main factor of pollution. As average temperature increases, habitats, species and people are threatened by drought, changes in rainfall, altered seasons, and more violent storms and floods. Indeed the life cycle of nuclear power results in relatively little pollution. Energy efficiency, solar, wind and other renewable fuels are other weapons against global warming . Human activity, primarily burning fossil fuels, is the major driving factor in global warming . Curtailing the release of carbon dioxide into the atmosphere by reducing use of oil, gasoline, coal and employment of alternate energy, sources are the tools for keeping global warming under control. global warming can be slowed and stopped, with practical actions thal yield a cleaner, healthier atmosphere

  17. Controlling indoor climate. Passive cooling of residential buildings in hot-humid climates in China

    Energy Technology Data Exchange (ETDEWEB)

    Wang Zhiwu

    1996-10-01

    Overheating is a paramount problem in residential buildings in hot and humid climates in China during summer. This study aims to deal with the overheating problem and the problem of poor air quality in dwellings. The main objective is to improve indoor thermal conditions by passive cooling approaches, climatisation techniques in buildings without auxiliary cooling from air conditioning equipment. This thesis focuses on the study of cross-ventilation in apartments, which is one of the most effective ways of natural cooling in a hot humid climate, but is also one of the least understood parts in controlling indoor climate. The Computational Fluid Dynamics (CFD) technique is used, which is a new approach, since cross-ventilation studies have been conventionally made by wind tunnel tests. The validations of the CFD technique are examined by a comparison between wind tunnel tests and computer simulations. The factors influencing indoor air movement are investigated for a single room. Cross-ventilation in two apartments is studied, and the air change efficiency in a Chinese kitchen is calculated with CFD techniques. The thermal performance of ventilated roofs, a simple and widely used type of roof in the region, is specially addressed by means of a full-scale measurement, wind tunnel tests and computer simulations. An integrated study of passive cooling approaches and factors affecting indoor thermal comfort is carried out through a case study in a southern Chinese city, Guangzhou. This thesis demonstrates that passive cooling measure have a high potential in significantly improving indoor thermal conditions during summer. This study also gives discussions and conclusions on the evaluation of indoor thermal environment; effects influencing cross-ventilation in apartments; design guidelines for ventilated roofs and an integrated study of passive cooling. 111 refs, 83 figs, 65 tabs

  18. Climatic factors influencing triatomine occurrence in Central-West Brazil

    Directory of Open Access Journals (Sweden)

    Joyce Mendes Pereira

    2013-05-01

    Full Text Available We estimated the geographic distributions of triatomine species in Central-West Region of Brazil (CW and analysed the climatic factors influencing their occurrence. A total of 3,396 records of 27 triatomine species were analysed. Using the maximum entropy method, ecological niche models were produced for eight species occurring in at least 20 municipalities based on 13 climatic variables and elevation. Triatoma sordida and Rhodnius neglectus were the species with the broadest geographic distributions in CW Brazil. The Cerrado areas in the state of Goiás were found to be more suitable for the occurrence of synanthropic triatomines than the Amazon forest areas in the northern part of the state of Mato Grosso. The variable that best explains the evaluated models is temperature seasonality. The results indicate that almost the entire region presents climatic conditions that are appropriate for at least one triatomine species. Therefore, it is recommended that entomological surveillance be reinforced in CW Brazil.

  19. Climatic controls on arid continental basin margin systems

    Science.gov (United States)

    Gough, Amy; Clarke, Stuart; Richards, Philip; Milodowski, Antoni

    2016-04-01

    Alluvial fans are both dominant and long-lived within continental basin margin systems. As a result, they commonly interact with a variety of depositional systems that exist at different times in the distal extent of the basin as the basin evolves. The deposits of the distal basin often cycle between those with the potential to act as good aquifers and those with the potential to act as good aquitards. The interactions between the distal deposits and the basin margin fans can have a significant impact upon basin-scale fluid flow. The fans themselves are commonly considered as relatively homogeneous, but their sedimentology is controlled by a variety of factors, including: 1) differing depositional mechanisms; 2) localised autocyclic controls; 3) geometrical and temporal interactions with deposits of the basin centre; and, 4) long-term allocyclic climatic variations. This work examines the basin margin systems of the Cutler Group sediments of the Paradox Basin, western U.S.A and presents generalised facies models for the Cutler Group alluvial fans as well as for the zone of interaction between these fans and the contemporaneous environments in the basin centre, at a variety of scales. Small-scale controls on deposition include climate, tectonics, base level and sediment supply. It has been ascertained that long-term climatic alterations were the main control on these depositional systems. Models have been constructed to highlight how both long-term and short-term alterations in the climatic regime can affect the sedimentation in the basin. These models can be applied to better understand similar, but poorly exposed, alluvial fan deposits. The alluvial fans of the Brockram Facies, northern England form part of a once-proposed site for low-level nuclear waste decommissioning. As such, it is important to understand the sedimentology, three-dimensional geometry, and the proposed connectivity of the deposits from the perspective of basin-scale fluid flow. The developed

  20. Climatic controls on diffuse groundwater recharge across Australia

    Directory of Open Access Journals (Sweden)

    O. V. Barron

    2012-12-01

    Full Text Available Reviews of field studies of groundwater recharge have attempted to investigate how climate characteristics control recharge, but due to a lack of data have not been able to draw any strong conclusions beyond that rainfall is the major determinant. This study has used numerical modelling for a range of Köppen-Geiger climate types (tropical, arid and temperate to investigate the effect of climate variables on recharge for different soil and vegetation types. For the majority of climate types, the correlation between the modelled recharge and total annual rainfall is weaker than the correlation between recharge and the annual rainfall parameters reflecting rainfall intensity. Under similar soil and vegetation conditions for the same annual rainfall, annual recharge in regions with winter-dominated rainfall is greater than in regions with summer-dominated rainfall. The importance of climate parameters other than rainfall in recharge estimation is highest in the tropical climate type. Mean annual values of solar radiation and vapour pressure deficit show a greater importance in recharge estimation than mean annual values of the daily mean temperature. Climate parameters have the lowest relative importance in recharge estimation in the arid climate type (with cold winters and the temperate climate type. For 75% of all soil, vegetation and climate types investigated, recharge elasticity varies between 2 and 4 indicating a 20% to 40% change in recharge for a 10% change in annual rainfall. Understanding how climate controls recharge under the observed historical climate allows more informed choices of analogue sites if they are to be used for climate change impact assessments.

  1. Methane : its role in climate change and options for control

    NARCIS (Netherlands)

    Amstel, van A.R.

    2012-01-01

    This study on CH4, (its role in climate change and options for control), aimed at a scenario analysis to assess future climate change under reduced methane emissions. At the same time improving the quality of CH4 emission inventories and estimating the costs of emission reducti

  2. Climatic controls on the pace of glacier erosion

    Science.gov (United States)

    Koppes, Michele; Hallet, Bernard; Rignot, Eric; Mouginot, Jeremie; Wellner, Julia; Love, Katherine

    2016-04-01

    Mountain ranges worldwide have undergone large-scale modification due the erosive action of ice, yet the mechanisms that control the timing of this modification and the rate by which ice erodes remain poorly understood. Available data report a wide range of erosion rates from individual ice masses over varying timescales, suggesting that modern erosion rates exceed orogenic rates by 2-3 orders of magnitude. These modern rates are presumed to be due to dynamic acceleration of the ice masses during deglaciation and retreat. Recent numerical models have focused on replicating the processes that produce the geomorphic signatures of glacial landscapes. Central to these models is a simple quantitative index that relates erosion rate to ice dynamics and to climate. To provide such an index, we examined explicitly the factors controlling modern glacier erosion rates across climatic regimes. Holding tectonic history, bedrock lithology and glacier hypsometries relatively constant across a latitudinal transect from Patagonia to the Antarctic Peninsula, we find that modern, basin-averaged erosion rates vary by three orders of magnitude, from 1->10 mm yr-1 for temperate tidewater glaciers to 0.01-ELA, in accord with theory. The general relationship between ice dynamics and erosion suggests that the erosion rate scales non-linearly with basal sliding speed, with an exponent n ≈ 2-2.62. Notably, erosion rates decrease by over two orders of magnitude between temperate and polar glaciers with similar ice discharge rates. The difference in erosion rates between temperate and colder glaciers of similar shape and size is primarily related to the abundance of meltwater accessing the bed. Since all glaciers worldwide have experienced colder than current climatic conditions, the 100-fold decrease in long-term relative to modern erosion rates may in part reflect the temporal averaging of warm and cold-based conditions over the lifecycle of these glaciers. Higher temperatures and

  3. Methane : its role in climate change and options for control

    OpenAIRE

    Amstel, van, R.J.

    2012-01-01

    This study on CH4, (its role in climate change and options for control), aimed at a scenario analysis to assess future climate change under reduced methane emissions. At the same time improving the quality of CH4 emission inventories and estimating the costs of emission reductions between 2010 and 2100. In this thesis 28 major options to control or mitigate methane emissions from different sources were identified. The effectiveness and costs of these options were assessed. This resulted in a ...

  4. Heart Disease Risk Factors You Can Control

    Science.gov (United States)

    ... disease: Know your risk Heart Health and Stroke Heart disease risk factors you can control Did you know? ... overall health. Return to top More information on Heart disease risk factors you can control Read more from ...

  5. Development of a variable climate controlled portable storage facility

    Science.gov (United States)

    Timmins, Mitchel; Yadav, Kamal; Iroanusi, Kennedy; Tickle, Andrew J.

    2012-10-01

    This paper focuses on the development of a portable variable climate controlled system that can be tailored to the requirements of the item to be stored by manipulating the temperature, humidity and light levels within the controlled area. This could be used to store anything from bio-chemical samples (to preserve them from field work) to cooled electronics (prior to deployment in a given situation) to foodstuffs (such as wine and other alcohols). In this situation however, to provide a relatively simplistic example, the environment will be used to store wine. The system is adaptive in that anything can be stored within it, assuming the storage parameters are known in order to correctly configure the environment. In this paper a microcontroller (PICF4520) is connected to a fridge with various sensors attached to monitor and manipulate the environment and adjust it accordingly. For the chosen item to be stored, a temperature of 13- 14oC is required, a high humidity level and a non-Ultraviolent (UV) light source. This work thus allows for a small handheld unit that could be used to control the climate within without the need for the traditional 12 - 16 foot size portable units traditionally used. The unit could be left in the field and run off a solar cell to assist in longer term studies. This paper presents how the microcontroller is connected to the fridge and its sensors, how it manipulates the environment and the process by which the temperature and other factors can be changed without having to edit and recompile the C code, this allows for a much more friendly device interface.

  6. Factors Influencing Smallholder Farmers' Climate Change Perceptions: A Study from Farmers in Ethiopia.

    Science.gov (United States)

    Habtemariam, Lemlem Teklegiorgis; Gandorfer, Markus; Kassa, Getachew Abate; Heissenhuber, Alois

    2016-08-01

    Factors influencing climate change perceptions have vital roles in designing strategies to enrich climate change understanding. Despite this, factors that influence smallholder farmers' climate change perceptions have not yet been adequately studied. As many of the smallholder farmers live in regions where climate change is predicted to have the most negative impact, their climate change perception is of particular interest. In this study, based on data collected from Ethiopian smallholder farmers, we assessed farmers' perceptions and anticipations of past and future climate change. Furthermore, the factors influencing farmers' climate change perceptions and the relation between farmers' perceptions and available public climate information were assessed. Our findings revealed that a majority of respondents perceive warming temperatures and decreasing rainfall trends that correspond with the local meteorological record. Farmers' perceptions about the past climate did not always reflect their anticipations about the future. A substantial number of farmers' anticipations of future climate were less consistent with climate model projections. The recursive bivariate probit models employed to explore factors affecting different categories of climate change perceptions illustrate statistical significance for explanatory variables including location, gender, age, education, soil fertility status, climate change information, and access to credit services. The findings contribute to the literature by providing evidence not just on farmers' past climate perceptions but also on future climate anticipations. The identified factors help policy makers to provide targeted extension and advisory services to enrich climate change understanding and support appropriate farm-level climate change adaptations.

  7. Factors Influencing Smallholder Farmers' Climate Change Perceptions: A Study from Farmers in Ethiopia.

    Science.gov (United States)

    Habtemariam, Lemlem Teklegiorgis; Gandorfer, Markus; Kassa, Getachew Abate; Heissenhuber, Alois

    2016-08-01

    Factors influencing climate change perceptions have vital roles in designing strategies to enrich climate change understanding. Despite this, factors that influence smallholder farmers' climate change perceptions have not yet been adequately studied. As many of the smallholder farmers live in regions where climate change is predicted to have the most negative impact, their climate change perception is of particular interest. In this study, based on data collected from Ethiopian smallholder farmers, we assessed farmers' perceptions and anticipations of past and future climate change. Furthermore, the factors influencing farmers' climate change perceptions and the relation between farmers' perceptions and available public climate information were assessed. Our findings revealed that a majority of respondents perceive warming temperatures and decreasing rainfall trends that correspond with the local meteorological record. Farmers' perceptions about the past climate did not always reflect their anticipations about the future. A substantial number of farmers' anticipations of future climate were less consistent with climate model projections. The recursive bivariate probit models employed to explore factors affecting different categories of climate change perceptions illustrate statistical significance for explanatory variables including location, gender, age, education, soil fertility status, climate change information, and access to credit services. The findings contribute to the literature by providing evidence not just on farmers' past climate perceptions but also on future climate anticipations. The identified factors help policy makers to provide targeted extension and advisory services to enrich climate change understanding and support appropriate farm-level climate change adaptations. PMID:27179801

  8. Factors Influencing Smallholder Farmers' Climate Change Perceptions: A Study from Farmers in Ethiopia

    Science.gov (United States)

    Habtemariam, Lemlem Teklegiorgis; Gandorfer, Markus; Kassa, Getachew Abate; Heissenhuber, Alois

    2016-08-01

    Factors influencing climate change perceptions have vital roles in designing strategies to enrich climate change understanding. Despite this, factors that influence smallholder farmers' climate change perceptions have not yet been adequately studied. As many of the smallholder farmers live in regions where climate change is predicted to have the most negative impact, their climate change perception is of particular interest. In this study, based on data collected from Ethiopian smallholder farmers, we assessed farmers' perceptions and anticipations of past and future climate change. Furthermore, the factors influencing farmers' climate change perceptions and the relation between farmers' perceptions and available public climate information were assessed. Our findings revealed that a majority of respondents perceive warming temperatures and decreasing rainfall trends that correspond with the local meteorological record. Farmers' perceptions about the past climate did not always reflect their anticipations about the future. A substantial number of farmers' anticipations of future climate were less consistent with climate model projections. The recursive bivariate probit models employed to explore factors affecting different categories of climate change perceptions illustrate statistical significance for explanatory variables including location, gender, age, education, soil fertility status, climate change information, and access to credit services. The findings contribute to the literature by providing evidence not just on farmers' past climate perceptions but also on future climate anticipations. The identified factors help policy makers to provide targeted extension and advisory services to enrich climate change understanding and support appropriate farm-level climate change adaptations.

  9. Temporal trend and climate factors of hemorrhagic fever with renal syndrome epidemic in Shenyang City, China

    Directory of Open Access Journals (Sweden)

    Liu Xiaodong

    2011-12-01

    was composed of three principal components and two autocorrelation terms. The association between HFRS epidemics and climate factors was better explained in the PCR model (F = 446.452, P R2 = 0.75 than in the general multiple regression model (F = 223.670, P R2 = 0.51. Conclusion The temporal distribution of HFRS in Shenyang varied in different years with a distinctly declining trend. The monthly trends of HFRS were significantly associated with local temperature, relative humidity, precipitation, air pressure, and wind velocity of the different previous months. The model conducted in this study will make HFRS surveillance simpler and the control of HFRS more targeted in Shenyang.

  10. Climatic and landscape controls on effective discharge

    Science.gov (United States)

    Basso, S.; Frascati, A.; Marani, M.; Schirmer, M.; Botter, G.

    2015-10-01

    The effective discharge constitutes a key concept in river science and engineering. Notwithstanding many years of studies, a full understanding of the effective discharge determinants is still challenged by the variety of values identified for different river catchments. The present paper relates the observed diversity of effective discharge to the underlying heterogeneity of flow regimes. An analytic framework is proposed, which links the effective ratio (i.e., the ratio between effective discharge and mean streamflow) to the empirical exponent of the sediment rating curve and to the streamflow variability, resulting from climatic and landscape drivers. The analytic formulation predicts patterns of effective ratio versus streamflow variability observed in a set of catchments of the continental United States and helps in disentangling the major climatic and landscape drivers of sediment transport in rivers. The findings highlight larger effective ratios of erratic hydrologic regimes (characterized by high flow variability) compared to those exhibited by persistent regimes, which are attributable to intrinsically different streamflow dynamics. The framework provides support for the estimate of effective discharge in rivers belonging to diverse climatic areas.

  11. Climatic change controls productivity variation in global grasslands.

    Science.gov (United States)

    Gao, Qingzhu; Zhu, Wenquan; Schwartz, Mark W; Ganjurjav, Hasbagan; Wan, Yunfan; Qin, Xiaobo; Ma, Xin; Williamson, Matthew A; Li, Yue

    2016-05-31

    Detection and identification of the impacts of climate change on ecosystems have been core issues in climate change research in recent years. In this study, we compared average annual values of the normalized difference vegetation index (NDVI) with theoretical net primary productivity (NPP) values based on temperature and precipitation to determine the effect of historic climate change on global grassland productivity from 1982 to 2011. Comparison of trends in actual productivity (NDVI) with climate-induced potential productivity showed that the trends in average productivity in nearly 40% of global grassland areas have been significantly affected by climate change. The contribution of climate change to variability in grassland productivity was 15.2-71.2% during 1982-2011. Climate change contributed significantly to long-term trends in grassland productivity mainly in North America, central Eurasia, central Africa, and Oceania; these regions will be more sensitive to future climate change impacts. The impacts of climate change on variability in grassland productivity were greater in the Western Hemisphere than the Eastern Hemisphere. Confirmation of the observed trends requires long-term controlled experiments and multi-model ensembles to reduce uncertainties and explain mechanisms.

  12. Variation in Rubisco content and activity under variable climatic factors.

    Science.gov (United States)

    Galmés, Jeroni; Aranjuelo, Iker; Medrano, Hipólito; Flexas, Jaume

    2013-11-01

    The main objective of the present review is to provide a compilation of published data of the effects of several climatic conditions on Rubisco, particularly its activity, state of activation, and concentration, and its influence on leaf gas exchange and photosynthesis. The environmental conditions analyzed include drought, salinity, heavy metals, growth temperature, and elevated [O3], [CO2], and ultraviolet-B irradiance. The results show conclusive evidence for a major negative effect on activity of Rubisco with increasing intensity of a range of abiotic stress factors. This decrease in the activity of Rubisco is associated with down-regulation of the activation state of the enzyme (e.g., by de-carbamylation and/or binding of inhibitory sugar phosphates) in response to drought or high temperature. On the contrary, the negative effects of low temperature, heavy metal stress (cadmium), ozone, and UV-B stress on Rubisco activity are associated with changes in the concentration of Rubisco. Notably, in response to all environmental factors, the regulation of in vivo CO2 assimilation rate was related to Rubisco in vitro parameters, either concentration and/or carboxylation, depending on the particular stress. The importance of the loss of Rubisco activity and its repercussion on plant photosynthesis are discussed in the context of climate change. It is suggested that decreased Rubisco activity will be a major effect induced by climate change, which will need to be considered in any prediction model on plant productivity in the near future.

  13. Climate Control Load Reduction Strategies for Electric Drive Vehicles in Warm Weather

    Energy Technology Data Exchange (ETDEWEB)

    Jeffers, M. A.; Chaney, L.; Rugh, J. P.

    2015-04-30

    Passenger compartment climate control is one of the largest auxiliary loads on a vehicle. Like conventional vehicles, electric vehicles (EVs) require climate control to maintain occupant comfort and safety, but cabin heating and air conditioning have a negative impact on driving range for all electric vehicles. Range reduction caused by climate control and other factors is a barrier to widespread adoption of EVs. Reducing the thermal loads on the climate control system will extend driving range, thereby reducing consumer range anxiety and increasing the market penetration of EVs. Researchers at the National Renewable Energy Laboratory have investigated strategies for vehicle climate control load reduction, with special attention toward EVs. Outdoor vehicle thermal testing was conducted on two 2012 Ford Focus Electric vehicles to evaluate thermal management strategies for warm weather, including solar load reduction and cabin pre-ventilation. An advanced thermal test manikin was used to assess a zonal approach to climate control. In addition, vehicle thermal analysis was used to support testing by exploring thermal load reduction strategies, evaluating occupant thermal comfort, and calculating EV range impacts. Through stationary cooling tests and vehicle simulations, a zonal cooling configuration demonstrated range improvement of 6%-15%, depending on the drive cycle. A combined cooling configuration that incorporated thermal load reduction and zonal cooling strategies showed up to 33% improvement in EV range.

  14. Evaluating the effect of climate change on areal reduction factors using regional climate model projections

    Science.gov (United States)

    Li, Jingwan; Sharma, Ashish; Johnson, Fiona; Evans, Jason

    2015-09-01

    Areal reduction factors (ARFs) are commonly used to transform point design rainfall to represent the average design rainfall for a catchment area. While there has been considerable attention paid in the research and engineering communities to the likely changes in rainfall intensity in future climates, the issue of changes to design areal rainfall has been largely ignored. This paper investigates the impact of climate change on ARFs. A new methodology for estimating changes in ARFs is presented. This method is used to assess changes in ARFs in the greater Sydney region using a high-resolution regional climate model (RCM). ARFs under present (1990-2009) and future (2040-2059) climate conditions were derived and compared for annual exceedance probabilities (AEPs) from 50% to 5% for durations ranging from 1 h to 120 h. The analysis shows two main trends in the future changes in ARFs. For the shortest duration events (1-h) the ARFs are found to increase which implies that these events will tend to have a larger spatial structure in the future than the current climate. In contrast, storms with durations between 6 and 72 h are likely to have decreased ARFs in the future, suggesting a more restricted spatial coverage of storms under a warming climate. The extent of the decrease varies with event frequency and catchment size. The largest decreases are found for large catchments and rare events. Although the results here are based on a single RCM and need to be confirmed in future work with multiple models, the framework that is proposed will be useful for future studies considering changes in the areal extent of rainfall extremes.

  15. Factors controlling contrail cirrus optical depth

    Directory of Open Access Journals (Sweden)

    B. Kärcher

    2009-08-01

    Full Text Available Aircraft contrails develop into contrail cirrus by depositional growth and sedimentation of ice particles and horizontal spreading due to wind shear. Factors controlling this development include temperature, ice supersaturation, thickness of ice-supersaturated layers, and vertical gradients in the horizontal wind field. An analytical microphysical cloud model is presented and validated that captures these processes. Many individual contrail cirrus are simulated that develop differently owing to the variability in the controlling factors, resulting in large samples of cloud properties that are statistically analyzed. Contrail cirrus development is studied over the first four hours past formation, similar to the ages of line-shaped contrails that were tracked in satellite imagery on regional scales. On these time scales, contrail cirrus optical depth and microphysical variables exhibit a marked variability, expressed in terms of broad and skewed probability distribution functions. Simulated mean optical depths at a wavelength of 0.55 μm range from 0.05-0.5 and a substantial fraction 20-50% of contrail cirrus stay subvisible (optical depth <0.02, depending on meteorological conditions.

    A detailed analysis based on an observational case study over the continental USA suggests that previous satellite measurements of line-shaped persistent contrails have missed about 89%, 50%, and 11% of contrails with optical depths 0-0.05, 0.05-0.1, and 0.1-0.2, respectively, amounting to 65% of contrail coverage of all optical depths. When comparing observations with simulations and when estimating the contrail cirrus climate impact, not only mean values but also the variability in optical depth and microphysical properties need to be considered.

  16. Factors controlling contrail cirrus optical depth

    Directory of Open Access Journals (Sweden)

    B. Kärcher

    2009-05-01

    Full Text Available Aircraft contrails develop into contrail cirrus by depositional growth and sedimentation of ice particles and horizontal spreading due to wind shear. Factors controlling this development include temperature, ice supersaturation, thickness of ice-supersaturated layers, and vertical gradients in the horizontal wind field. An analytical microphysical cloud model is presented and validated that captures these processes. Many individual contrail cirrus are simulated that develop differently owing to the variability in the controlling factors, resulting in large samples of cloud properties that are statistically analyzed. Contrail cirrus development is studied over the first four hours past formation, similar to the ages of contrails that were tracked in satellite imagery on regional scales. On these time scales, contrail cirrus optical depth and microphysical variables exhibit a marked variability, expressed in terms of broad and skewed probability distribution functions. Typical simulated mean optical depths at a wavelength of 0.55 μm are in the range 0.2–0.3. A substantial fraction 20–40% of contrail cirrus stay subvisible (optical depth <0.02. A detailed analysis suggests that previous satellite measurements of line-shaped persistent contrails have missed about 86% (35% of contrails with optical depth ≤0.05 (0.05–0.1, amounting to almost 50% of contrails of all optical depths. When comparing observations with simulations and when estimating the contrail cirrus climate impact, not only mean values but also the variability in optical depth and microphysical properties need to be considered.

  17. Industry, air and climate control; Industrie, protection de l'air et du climat

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-11-01

    Facing the fight against the climatic changes, the industry invests in processes to control the greenhouse effect gazes. This colloquium proposes to insist on the dialog between the public policy and the manufacturers, to make the state of the art on the performances evolution and the agreements and to present the financial and energetic cost of the pollution control. (A.L.B.)

  18. Modelling and (adaptive) control of greenhouse climates

    NARCIS (Netherlands)

    Udink ten Cate, A.J.

    1983-01-01

    The material presented in this thesis can be grouped around four themes, system concepts, modeling, control and adaptive control. In this summary these themes will be treated separately.System conceptsIn Chapters 1 and 2 an overview of the problem formulation is presented. It is suggested that there

  19. Climatic Control on Forests and Tree Species Distribution in the Forest Region of Northeast China

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    North-east (NE) China covers considerable climatic gradients and all major forests types of NE Asia. In the present study, 10 major forest types across the forest region of NE China were sampled to investigate forest distribution in relation to climate. Canonical correspondence analysis (CCA) revealed that growing season precipitation and energy availability were primary climatic factors for the overall forest pattern of NE China, accounting for 66% of the explanatory power of CCA. Conversely, annual precipitation and winter coldness had minor effects. Generalized additive models revealed that tree species responded to climatic gradients differently and showed three types of response curve: (i) monotonous decline; (ii) monotonous increase; and (iii) a unimodal pattern. Furthermore, tree species showed remarkable differences in limiting climatic factors for their distribution. The power of climate in explaining species distribution declined significantly with decreasing species dominance, suggesting that the distribution of dominant species was primarily controlled by climate, whereas that of subordinate species was more affected by competition from other species.

  20. SIGNAL DETECTION OF GLOBAL CLIMATE CHANGE AND EXTERNAL FORCING FACTORS

    Institute of Scientific and Technical Information of China (English)

    李晓东; 王在文; 侯章栓

    2001-01-01

    In this paper, we displayed one-dimensional climate signals, such as global temperature variation, Southern Oscillation Index and variation of external forcing factors, on a two-dimensional time-scale plane using compactly supported wavelet decomposition. Using the lag-correlation analysis method, and interpretative variance analysis method, and phase comparison method to the wavelet analysis result, we not only gained the variation on different scales to the global temperature and El Nino signals, the location of the jump point and intrinsic scale of these series, but also indicated the magnitude, extent and time of the effect of external forcing factors on them. We also put forward reasonable explanation to the main variation of recent 140 years.

  1. Organizational Climate: An Analysis of Factors and Influences.

    Science.gov (United States)

    Grace, Linda

    1986-01-01

    The author investigates the literature on organizational climate, presents an overview of aspects of such climate, and assesses areas needing further investigation. One problem is definition of the term "organizational climate." She stresses the need for clarification and special emphasis on the long-term nature of climate. (Author/CH)

  2. Causal Factors in Genome Control

    NARCIS (Netherlands)

    O'Duibhir, E.

    2015-01-01

    The aim of this thesis is to study how genes are switched on and off in a coordinated way across an entire genome. In order to do this yeast is used as a model organism. The mechanisms that control gene expression in yeast are very similar to those of human cells. Chapter 1 provides a general introd

  3. Austrian Daily Climate Data Rescue and Quality Control

    Science.gov (United States)

    Jurkovic, A.; Lipa, W.; Adler, S.; Albenberger, J.; Lechner, W.; Swietli, R.; Vossberg, I.; Zehetner, S.

    2010-09-01

    Checked climate datasets are a "conditio sine qua non" for all projects that are relevant for environment and climate. In the framework of climate change studies and analysis it is essential to work with quality controlled and trustful data. Furthermore these datasets are used as input for various simulation models. In regard to investigations of extreme events, like strong precipitation periods, drought periods and similar ones we need climate data in high temporal resolution (at least in daily resolution). Because of the historical background - during Second World War the majority of our climate sheets were sent to Berlin, where the historical sheets were destroyed by a bomb attack and so important information got lost - only several climate sheets, mostly duplicates, before 1939 are available and stored in our climate data archive. In 1970 the Central Institute for Meteorology and Geodynamics in Vienna started a first attempt to digitize climate data by means of punch cards. With the introduction of a routinely climate data quality control in 1984 we can speak of high-class-checked daily data (finally checked data, quality flag 6). Our group is working on the processing of digitization and quality control of the historical data for the period 1872 to 1983 for 18 years. Since 2007 it was possible to intensify the work (processes) in the framework of an internal project, namely Austrian Climate Data Rescue and Quality Control. The aim of this initiative was - and still is - to supply daily data in an outstanding good and uniform quality. So this project is a kind of pre-project for all scientific projects which are working with daily data. In addition to routine quality checks (that are running since 1984) using the commercial Bull Software we are testing our data with additional open source software, namely ProClim.db. By the use of this spatial and statistical test procedure, the elements air temperature and precipitation - for several sites in Carinthia - could

  4. The Influence of Safety Training on Safety Climate Factors in a Construction Site

    Directory of Open Access Journals (Sweden)

    MohammadJavad Jafari

    2015-10-01

    Full Text Available  Safety issues have always been put forward as one of the major problems and primary concerns in construction industries in many countries. This paper will focus on the impact of safety training on safety climate and its relevant factors in two sites of a construction firm. The Health and Safety Executive (HSE guide to safety climate tool that had been validated in Iran was used to determine the impacts of safety training on safety climate and its relevant factors. For this purpose, 347 workers filled out the questionnaire before and after safety training. The relationships between demographic features of workers and safety climate factors were considered in the questionnaire. Spearman's rho test was used to determine the relationship between safety climate factors. In both sites, there were significant differences (p<0.05 between safety climate factors before and after safety training while, the level of safety climate in both sites was the same before (p=0.416 and after (p=0.547 safety training. The results of Spearman's correlations test indicated that there has been a significant relationship (p<0.05 between safety climate and its relevant factors in both sites. The results showed that some safety climate factors such as pressure for production had been influenced by demographic factors such as age and job category. Safety training can improve the level of safety climate and its relevant factors in a construction industry. Improvement of each safety climate factor can promote the level of safety climate. Demographic features affected safety climate level and its relevant factors.

  5. An Analysis of the Relationship between Select Organizational Climate Factors and Job Satisfaction Factors as Reported by Community College Personnel

    Science.gov (United States)

    San Giacomo, Rose-Marie Carla

    2011-01-01

    The purpose of this study was to investigate the overall satisfaction with organizational climate factors across seven studies of various levels of community college personnel. A secondary purpose was to determine if there was a significant relationship between satisfaction with organizational climate factors and the importance of job satisfaction…

  6. Socio-economic factors influencing climate change adaptation among crop farmers in Umuahia South Area of Abia State, Nigeria

    Directory of Open Access Journals (Sweden)

    N. O. Anyoha

    2013-04-01

    Full Text Available The aim of the study was to determine the socioeconomic factors influencing climate change adaptation among crop farmers in Umuahia South Area of Abia State, Nigeria. The specific objectives of the study were to determine socioeconomic characteristics of crop farmers in the area, determine farmers level of awareness of climate change in the area, ascertain effects of climate change in crop production, identify adaptation strategies adopted by the farmers in the area and determine socioeconomic factors influencing adaptation to climate change. Data were collected through a questionnaire distributed to 120 farmers. Data were analyzed using descriptive statistical tools such as tables, likert type scale and multiple regression analysis. Results of data collected shows that the strategies adopted to combat the effects of climate change by farmers in the area include tree planting, cultivation of early maturing crops, mixed farming, use of improved crop varieties, increased use of family labour, engagement in complementary/diverse livelihoods, cover cropping, changes in planting and harvesting dates, irrigation practices, crop rotation, riverside/bank cultivation, increased frequency of weeding etc, Results reveal that farm size, farming experience, household size, and social organization (MEM COP were significant at 5%, sex was significant at 1% . Extension educational campaign should be intensified to increase the knowledge about climate change. Government should collaborate with meteorologists in forecasting about climate change and also in bringing about measures to control the adverse effect of climate change especially in agriculture.

  7. Modeling, Estimation and Control of Indoor Climate in Livestock Buildings

    DEFF Research Database (Denmark)

    Wu, Zhuang

    The main objective of this research is to design an efficient control system for the indoor climate of a large-scale partition-less livestock building, in order to maintain a healthy, comfortable and economically energy consuming indoor environment for the agricultural animals and farmers....... In this thesis, a conceptual multi-zone climate model is proposed according to the knowledge about the hybrid ventilation theory. The method is to compartmentalize the building into some well-mixed macroscopic homogeneous zones, with the major emphasizes on the occupied spaces where the animals confined in...... the resilience of the control system to disturbances beyond its bandwidth, increases the manipulators utilization efficiency, and reduces energy consumption by solving a constrained convex optimization. Through comparative simulation results analysis, the proposed modeling and control technique is proved...

  8. Estimating productivity of tropical forest plantations by climatic factors

    Energy Technology Data Exchange (ETDEWEB)

    Pandey, D.

    1996-12-31

    This study presents an alternative method of estimating wood production at regional/global levels from tropical plantations based on climatic variables. A generic model for estimating potential yield in tropical plantations was formulated. The model was developed for teak (Tectona grandis L. F.) as a case study. Available data of teak sample plots from India, Myanmar, Indonesia, Nigeria and Ivory Coast, consisting of 153 plots distributed over 38 meteorological stations were used. A new base age invariant site index function was developed and the site index of each plot was estimated. The mean annual volume increment (MAI) of each plot from existing yield tables was then interpolated. Treating MAI at 50 years (rotation age) as potential yield of teak, a model was constructed which could explain about 59% variance of the potential yield. Models constructed for estimating the maximum MAI and the site index of teak explained the variability up to 61% and 57% respectively. The models underestimated the productivity of teak in Indonesia, Nigeria and Ivory Coast. The rainfall and the relative humidity have been identified as the most important climatic variables influencing the growth of teak. The length of the growing season and the temperature of the warmest month of the growing season were found significant in the models. The temperature and the day length (sunshine) have not been found to be the limiting factors for the growth of teak. However, the maximum temperature beyond a certain upper limit has a negative effect on growth. The study indicates that this upper limit is around 33 deg C for teak. The models could be used to forecast the potential yield of the existing as well as planned teak plantations in the tropical region. 109 refs, 15 figs, 11 tabs

  9. Phase Detector for Power-Factor Controller

    Science.gov (United States)

    Nola, F. J.

    1984-01-01

    Positive feedback assures reliable switching. Three Phase Power Factor Controller includes three phase detectors, each produces rectangular waves of duration approximately equal to lag time between line voltage and motor current.

  10. Climate control of terrestrial carbon exchange across biomes and continents

    International Nuclear Information System (INIS)

    Understanding the relationships between climate and carbon exchange by terrestrial ecosystems is critical to predict future levels of atmospheric carbon dioxide because of the potential accelerating effects of positive climate-carbon cycle feedbacks. However, directly observed relationships between climate and terrestrial CO2 exchange with the atmosphere across biomes and continents are lacking. Here we present data describing the relationships between net ecosystem exchange of carbon (NEE) and climate factors as measured using the eddy covariance method at 125 unique sites in various ecosystems over six continents with a total of 559 site-years. We find that NEE observed at eddy covariance sites is (1) a strong function of mean annual temperature at mid- and high-latitudes, (2) a strong function of dryness at mid- and low-latitudes, and (3) a function of both temperature and dryness around the mid-latitudinal belt (45 deg. N). The sensitivity of NEE to mean annual temperature breaks down at ∼ 16 deg. C (a threshold value of mean annual temperature), above which no further increase of CO2 uptake with temperature was observed and dryness influence overrules temperature influence.

  11. Climate control of terrestrial carbon exchange across biomes and continents

    Energy Technology Data Exchange (ETDEWEB)

    Yi Chuixiang; Wolbeck, John; Xu Xiyan [School of Earth and Environmental Sciences, Queens College, City University of New York, NY 11367 (United States); Ricciuto, Daniel [Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Li Runze [Department of Statistics, Pennsylvania State University, University Park, PA 16802 (United States); Nilsson, Mats [Department of Forest Ecology, Swedish University of Agricultural Sciences, SE-901 83 Umeaa (Sweden); Aires, Luis [CESAM and Department of Environmental Engineering, School of Technology and Management, Polytechnic Institute of Leiria (Portugal); Albertson, John D [Department of Civil and Environmental Engineering, Duke University, Durham, NC 22708-0287 (United States); Ammann, Christof [Federal Research Station Agroscope Reckenholz-Taenikon, Reckenholzstrasse 191, 8046 Zuerich (Switzerland); Arain, M Altaf [School of Geography and Earth Sciences, McMaster University, Hamilton, ON, L8S 4K1 (Canada); De Araujo, Alessandro C [Instituto Nacional de Pesquisas da Amazonia, Programa LBA, Campus-II, Manaus-Amazonas 69060 (Brazil); Aubinet, Marc [University of Liege, Gembloux Agro-Bio Tech, Unit of Biosystem Physics, 2 Passage des Deportes, 5030 Gembloux (Belgium); Aurela, Mika [Finnish Meteorological Institute, Climate Change Research, FI-00101 Helsinki (Finland); Barcza, Zoltan [Department of Meteorology, Eoetvoes Lorand University, H-1117 Budapest, Pazmany setany 1/A (Hungary); Barr, Alan [Climate Research Division, Environment Canada, Saskatoon, SK, S7N 3H5 (Canada); Berbigier, Paul [INRA, UR1263 EPHYSE, Villenave d' Ornon F-33883 (France); Beringer, Jason [School of Geography and Environmental Science, Monash University, Clayton, Victoria 3800 (Australia); Bernhofer, Christian [Institute of Hydrology and Meteorology, Dresden University of Technology, Pienner Strasse 23, D-01737, Tharandt (Germany)

    2010-07-15

    Understanding the relationships between climate and carbon exchange by terrestrial ecosystems is critical to predict future levels of atmospheric carbon dioxide because of the potential accelerating effects of positive climate-carbon cycle feedbacks. However, directly observed relationships between climate and terrestrial CO{sub 2} exchange with the atmosphere across biomes and continents are lacking. Here we present data describing the relationships between net ecosystem exchange of carbon (NEE) and climate factors as measured using the eddy covariance method at 125 unique sites in various ecosystems over six continents with a total of 559 site-years. We find that NEE observed at eddy covariance sites is (1) a strong function of mean annual temperature at mid- and high-latitudes, (2) a strong function of dryness at mid- and low-latitudes, and (3) a function of both temperature and dryness around the mid-latitudinal belt (45 deg. N). The sensitivity of NEE to mean annual temperature breaks down at {approx} 16 deg. C (a threshold value of mean annual temperature), above which no further increase of CO{sub 2} uptake with temperature was observed and dryness influence overrules temperature influence.

  12. Energy efficient climate control for cut flower alstroemeria

    OpenAIRE

    Labrie, C.W.; Zwart, de, H.F.

    2012-01-01

    Like in most countries, in the Netherlands energy consumption is an increasing cost component. In cut flowers grown at a relatively low temperature, most of the energy is used for dehumidification. In Alstroemeria dehumidification is especially important to prevent the physiological disorder expressed as necrotic leaf tips. Research has been carried out showing that improved climate control can save 37% on heating, without a reduction on yield and even a quality, compared to a contemporary re...

  13. Computer Model for Automobile Climate Control System Simulation and Application

    Directory of Open Access Journals (Sweden)

    Emin Oker

    1999-06-01

    Full Text Available A software to simulate the dynamic operation of climate control system for a generic automobile has been developed. The transient nature of passenger cabin temperature and relative humidity are predicted using the principles of thermodynamics. Analysis include detailed simulations of every component of the automobile air conditioning network. The methodology is validated by comparing the simulation results with the experimental results.

  14. Complexity in Climatic Controls on Plant Species Distribution: Satellite Data Reveal Unique Climate for Giant Sequoia in the California Sierra Nevada

    Science.gov (United States)

    Waller, Eric Kindseth

    A better understanding of the environmental controls on current plant species distribution is essential if the impacts of such diverse challenges as invasive species, changing fire regimes, and global climate change are to be predicted and important diversity conserved. Climate, soil, hydrology, various biotic factors fire, history, and chance can all play a role, but disentangling these factors is a daunting task. Increasingly sophisticated statistical models relying on existing distributions and mapped climatic variables, among others, have been developed to try to answer these questions. Any failure to explain pattern with existing mapped climatic variables is often taken as a referendum on climate as a whole, rather than on the limitations of the particular maps or models. Every location has a unique and constantly changing climate so that any distribution could be explained by some aspect of climate. Chapter 1 of this dissertation reviews some of the major flaws in species distribution modeling and addresses concerns that climate may therefore not be predictive of, or even relevant to, species distributions. Despite problems with climate-based models, climate and climate-derived variables still have substantial merit for explaining species distribution patterns. Additional generation of relevant climate variables and improvements in other climate and climate-derived variables are still needed to demonstrate this more effectively. Satellite data have a long history of being used for vegetation mapping and even species distribution mapping. They have great potential for being used for additional climatic information, and for improved mapping of other climate and climate-derived variables. Improving the characterization of cloud cover frequency with satellite data is one way in which the mapping of important climate and climate-derived variables can be improved. An important input to water balance models, solar radiation maps could be vastly improved with a

  15. Empirical Investigation of Factors Contributing to the Psychological Safety Climate on Construction Sites

    OpenAIRE

    Shen, Y.; Koh, TY; Rowlinson, SM; Bridge, AJ

    2015-01-01

    Employees’ safety climate perceptions dictate their safety behavior because individuals act based on their perceptions of reality. Extensive empirical research in applied psychology has confirmed this relationship. However, rare efforts have been made to investigate the factors contributing to a favorable safety climate in construction research. As an initial effort to address the knowledge gap, this paper examines factors contributing to a psychological safety climate, an operationalization ...

  16. Climate factors influencing bacterial count in background air samples.

    Science.gov (United States)

    Harrison, Roy M; Jones, Alan M; Biggins, Peter D E; Pomeroy, Nigel; Cox, Christopher S; Kidd, Stephen P; Hobman, Jon L; Brown, Nigel L; Beswick, Alan

    2005-01-01

    Total (as opposed to culturable) bacterial number counts are reported for four sites in the United Kingdom measured during campaigns over four separate seasons. These are interpreted in relation to simple climatic factors, i.e. temperature, wind speed and wind direction. Temperature has a marked effect at all four sites with data for a rural coastal site conforming best to a simple exponential model. Data for the other rural and urban locations show a baseline similar to that determined at the coastal rural location, but with some very significant positive excursions. The temperature dependence of bacterial number is found to conform to that typical of bacterial growth rates. At the coastal rural location, bacterial numbers normalised for temperature show no dependence on wind speed whilst at the inland sites there is a decrease with increasing wind speed of the form expected for a large area source. Only one site appeared to show a systematic relationship of bacterial concentrations to wind direction that being a site in the suburbs of Birmingham with highest number concentrations observed on a wind sector approaching from the city centre. PCR techniques have been used to identify predominant types of bacteria and results are presented which show that Bacillus was the dominant genus observed at the three inland sites during the winter and summer seasons. Pseudomonas appeared with comparable frequency at certain sites and seasons. There was in general a greater diversity of bacteria at the coastal site than at the inland sites.

  17. Cholera outbreak in Senegal in 2005: was climate a factor?

    Directory of Open Access Journals (Sweden)

    Guillaume Constantin de Magny

    Full Text Available Cholera is an acute diarrheal illness caused by Vibrio cholerae and occurs as widespread epidemics in Africa. In 2005, there were 31,719 cholera cases, with 458 deaths in the Republic of Senegal. We retrospectively investigated the climate origin of the devastating floods in mid-August 2005, in the Dakar Region of Senegal and the subsequent outbreak of cholera along with the pattern of cholera outbreaks in three other regions of that country. We compared rainfall patterns between 2002 and 2005 and the relationship between the sea surface temperature (SST gradient in the tropical Atlantic Ocean and precipitation over Senegal for 2005. Results showed a specific pattern of rainfall throughout the Dakar region during August, 2005, and the associated rainfall anomaly coincided with an exacerbation of the cholera epidemic. Comparison of rainfall and epidemiological patterns revealed that the temporal dynamics of precipitation, which was abrupt and heavy, was presumably the determining factor. Analysis of the SST gradient showed that the Atlantic Ocean SST variability in 2005 differed from that of 2002 to 2004, a result of a prominent Atlantic meridional mode. The influence of this intense precipitation on cholera transmission over a densely populated and crowded region was detectable for both Dakar and Thiès, Senegal. Thus, high resolution rainfall forecasts at subseasonal time scales should provide a way forward for an early warning system in Africa for cholera and, thereby, trigger epidemic preparedness. Clearly, attention must be paid to both natural and human induced environmental factors to devise appropriate action to prevent cholera and other waterborne disease epidemics in the region.

  18. Cholera Outbreak in Senegal in 2005: Was Climate a Factor?

    Science.gov (United States)

    Constantin de Magny, Guillaume; Thiaw, Wassila; Kumar, Vadlamani; Manga, Noël M.; Diop, Bernard M.; Gueye, Lamine; Kamara, Mamina; Roche, Benjamin; Murtugudde, Raghu; Colwell, Rita R.

    2012-01-01

    Cholera is an acute diarrheal illness caused by Vibrio cholerae and occurs as widespread epidemics in Africa. In 2005, there were 31,719 cholera cases, with 458 deaths in the Republic of Senegal. We retrospectively investigated the climate origin of the devastating floods in mid-August 2005, in the Dakar Region of Senegal and the subsequent outbreak of cholera along with the pattern of cholera outbreaks in three other regions of that country. We compared rainfall patterns between 2002 and 2005 and the relationship between the sea surface temperature (SST) gradient in the tropical Atlantic Ocean and precipitation over Senegal for 2005. Results showed a specific pattern of rainfall throughout the Dakar region during August, 2005, and the associated rainfall anomaly coincided with an exacerbation of the cholera epidemic. Comparison of rainfall and epidemiological patterns revealed that the temporal dynamics of precipitation, which was abrupt and heavy, was presumably the determining factor. Analysis of the SST gradient showed that the Atlantic Ocean SST variability in 2005 differed from that of 2002 to 2004, a result of a prominent Atlantic meridional mode. The influence of this intense precipitation on cholera transmission over a densely populated and crowded region was detectable for both Dakar and Thiès, Senegal. Thus, high resolution rainfall forecasts at subseasonal time scales should provide a way forward for an early warning system in Africa for cholera and, thereby, trigger epidemic preparedness. Clearly, attention must be paid to both natural and human induced environmental factors to devise appropriate action to prevent cholera and other waterborne disease epidemics in the region. PMID:22952995

  19. International colloquium challenge climate for the France: the factor 4; Colloque international defi climat pour la France: le facteur 4

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    The objective factor 4 is the division by four of the greenhouse gases emission. This colloquium aims to define possible actions to reach this objective. The first part concerns presentations of personalities of the domain and offers an international panorama of the energetic and environmental policies, against the climatic change and how to reconcile economic growth with climatic change. The second part wonders on the mobilization of the actors secton a national and international framework. (A.L.B.)

  20. Estimation of climate factors for future extreme rainfall: Comparing observations and RCM simulations

    DEFF Research Database (Denmark)

    Gregersen, Ida Bülow; Madsen, H.; Arnbjerg-Nielsen, Karsten

    2011-01-01

    The application of climate factors has become more common in urban drainage design. The climate factor accounts for the expected increase in the magnitude of the extreme rainfall events during the technical lifetime of the drainage system. The present practice in Denmark is the application of cli...

  1. Climate controls on dust storm occurrence in Maowusu Desert, Inner Mongolia, North China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Dust storms occurring in arid and semi-arid regions play a main role in the evolution of landscapes. Climate is generally regarded to be important factors influencing the occurrence of dust storm, however, the way of climate controlling dust storms had been poorly understood. In this paper, we present the Ew Index model to describe the relationship between climate variables and dust storm frequency using the available meteorological data from three meteorological stations in Maowusu Desert. This index model explains 96.8%, 69.8% and 65.3% of the variance of dust storm frequency in three regions from the north to the south,respectively and this difference is probably caused by the difference of the human disturbance. The Ew Index model is an effective predictor of dust storm frequency and provides us a quite good understanding on the occurrence of dust storms in Maowusu Desert.

  2. Climate and soil factors influencing seedling recruitment of plant species used for dryland restoration

    Science.gov (United States)

    Muñoz-Rojas, Miriam; Erickson, Todd E.; Martini, Dylan C.; Dixon, Kingsley W.; Merritt, David J.

    2016-06-01

    Land degradation affects 10-20 % of drylands globally. Intensive land use and management, large-scale disturbances such as extractive operations, and global climate change, have contributed to degradation of these systems worldwide. Restoring these damaged environments is critical to improving ecosystem services and functions, conserve biodiversity, and contribute to climate resilience, food security, and landscape sustainability. Here, we present a case study on plant species of the mining intensive semi-arid Pilbara region in Western Australia that examines the effects of climate and soil factors on the restoration of drylands. We analysed the effects of a range of rainfall and temperature scenarios and the use of alternative soil materials on seedling recruitment of key native plant species from this area. Experimental studies were conducted in controlled environment facilities where conditions simulated those found in the Pilbara. Soil from topsoil (T) stockpiles and waste materials (W) from an active mine site were mixed at different proportions (100 % T, 100 % W, and two mixes of topsoil and waste at 50 : 50 and 25 : 75 ratios) and used as growth media. Our results showed that seedling recruitment was highly dependent on soil moisture and emergence was generally higher in the topsoil, which had the highest available water content. In general, responses to the climate scenarios differed significantly among the native species which suggest that future climate scenarios of increasing drought might affect not only seedling recruitment but also diversity and structure of native plant communities. The use of waste materials from mining operations as growth media could be an alternative to the limited topsoil. However, in the early stages of plant establishment successful seedling recruitment can be challenging in the absence of water. These limitations could be overcome by using soil amendments but the cost associated to these solutions at large landscape scales

  3. Climate controls on forest productivity along the climate gradient of the western Sierra Nevada

    Science.gov (United States)

    Kelly, A. E.; Goulden, M. L.

    2010-12-01

    The broad climate gradient of the slopes of the western Sierra Nevada mountains supports ecosystems spanning extremes of productivity, biomass, and function. We are using this natural environmental gradient to understand how climate controls NPP, aboveground biomass, species' range limits, and phenology. Our experimental approach combines eddy covariance, sap flow, dendrometer, and litterfall measurements in combination with soil and hydrological data from the Southern Sierra Critical Zone Observatory (SSCZO). We have found that above about 2500 m, forest productivity is limited by winter cold, while below 1200 m, productivity is likely limited by summer drought. The sweet spot between these elevations has a nearly year-long growing season despite a snowpack that persists for as long as six months. Our results show that small differences in temperature can markedly alter the water balance and productivity of mixed conifer forests.

  4. Winter climate change: a critical factor for temperate vegetation performance.

    Science.gov (United States)

    Kreyling, Juergen

    2010-07-01

    Winter ecological processes are important drivers of vegetation and ecosystem functioning in temperate ecosystems. There, winter conditions are subject to rapid climate change. The potential loss of a longer-lasting snow cover with implications to other plant-related climate parameters and overwintering strategies make the temperate zone particularly vulnerable to winter climate change. A formalized literature search in the ISI Web of Science shows that plant related research on the effects of winter climate change is generally underrepresented. Temperate regions in particular are rarely studied in this respect, although the few existing studies imply strong effects of winter climate change on species ranges, species compositions, phenology, or frost injury. The generally positive effect of warming on plant survival and production may be counteracted by effects such as an increased frost injury of roots and shoots, an increased insect pest risk, or a disrupted synchrony between plants and pollinators. Based on the literature study, gaps in current knowledge are discussed. Understanding the relative effects of interacting climate parameters, as well as a stronger consideration of shortterm events and variability of climatic conditions is urgent. With respect to plant response, it would be particularly worthwhile to account for hidden players such as pathogens, pollinators, herbivores, or fungal partners in mycorrhization.

  5. Winter climate change: a critical factor for temperate vegetation performance.

    Science.gov (United States)

    Kreyling, Juergen

    2010-07-01

    Winter ecological processes are important drivers of vegetation and ecosystem functioning in temperate ecosystems. There, winter conditions are subject to rapid climate change. The potential loss of a longer-lasting snow cover with implications to other plant-related climate parameters and overwintering strategies make the temperate zone particularly vulnerable to winter climate change. A formalized literature search in the ISI Web of Science shows that plant related research on the effects of winter climate change is generally underrepresented. Temperate regions in particular are rarely studied in this respect, although the few existing studies imply strong effects of winter climate change on species ranges, species compositions, phenology, or frost injury. The generally positive effect of warming on plant survival and production may be counteracted by effects such as an increased frost injury of roots and shoots, an increased insect pest risk, or a disrupted synchrony between plants and pollinators. Based on the literature study, gaps in current knowledge are discussed. Understanding the relative effects of interacting climate parameters, as well as a stronger consideration of shortterm events and variability of climatic conditions is urgent. With respect to plant response, it would be particularly worthwhile to account for hidden players such as pathogens, pollinators, herbivores, or fungal partners in mycorrhization. PMID:20715613

  6. Dominant climatic factor driving annual runoff change at catchments scale over China

    Directory of Open Access Journals (Sweden)

    Z. Huang

    2015-12-01

    Full Text Available With global climate changes intensifying, the hydrological response to climate changes has attracted more attentions. It is beneficial not only for hydrology and ecology but also for water resources planning and management to reveal the impacts of climate change on runoff. It is of great significance of climate elasticity of runoff to estimate the impacts of climatic factors on runoff. In addition, there are large spatial variations in climate type and geography characteristics over China. To get a better understanding the spatial variation of runoff response to climate variables change and detect the dominant climatic factor driving annual runoff change, we chose the climate elasticity method proposed by Yang and Yang (2011, where the impact of the catchment characteristics on runoff was represented by a parameter n. The results show that the dominant climatic factor driving annual runoff is precipitation in the most part of China, net radiation in the lower reach of Yangtze River Basin, the Pearl River Basin, the Huai River Basin and the southeast area, and wind speed in part of the northeast China.

  7. The impact of climatic risk factors on the prevalence, distribution, and severity of acute and chronic trachoma.

    Directory of Open Access Journals (Sweden)

    Anita Ramesh

    2013-11-01

    Full Text Available BACKGROUND AND OBJECTIVES: Trachoma is the most common cause of infectious blindness. Hot, dry climates, dust and water scarcity are thought to be associated with the distribution of trachoma but the evidence is unclear. The aim of this study was to evaluate the epidemiological evidence regarding the extent to which climatic factors explain the current prevalence, distribution, and severity of acute and chronic trachoma. Understanding the present relationship between climate and trachoma could help inform current and future disease elimination. METHODS: A systematic review of peer-reviewed literature was conducted to identify observational studies which quantified an association between climate factors and acute or chronic trachoma and which met the inclusion and exclusion criteria. Studies that assessed the association between climate types and trachoma prevalence were also reviewed. RESULTS: Only eight of the 1751 papers retrieved met the inclusion criteria, all undertaken in Africa. Several papers reported an association between trachoma prevalence and altitude in highly endemic areas, providing some evidence of a role for temperature in the transmission of acute disease. A robust mapping study found strong evidence of an association between low rainfall and active trachoma. There is also consistent but weak evidence that the prevalence of trachoma is higher in savannah-type ecological zones. There were no studies on the effect of climate in low endemic areas, nor on the effect of dust on trachoma. CONCLUSION: Current evidence on the potential role of climate on trachoma distribution is limited, despite a wealth of anecdotal evidence. Temperature and rainfall appear to play a role in the transmission of acute trachoma, possibly mediated through reduced activity of flies at lower temperatures. Further research is needed on climate and other environmental and behavioural factors, particularly in arid and savannah areas. Many studies did not

  8. Controls on soil microbial community stability under climate change

    Directory of Open Access Journals (Sweden)

    Franciska T De Vries

    2013-09-01

    Full Text Available Soil microbial communities are intricately linked to ecosystem functioning because they play important roles in carbon and nitrogen cycling. Still, we know little about how soil microbial communities will be affected by disturbances expected with climate change. This is a significant gap in understanding, as the stability of microbial communities, defined as a community's ability to resist and recover from disturbances, likely has consequences for ecosystem function. Here, we propose a framework for predicting a community’s response to climate change, based on specific functional traits present in the community, the relative dominance of r- and K-strategists, and the soil environment. We hypothesize that the relative abundance of r- and K-strategists will inform about a community’s resistance and resilience to climate change associated disturbances. We also propose that other factors specific to soils, such as moisture content and the presence of plants, may enhance a community’s resilience. For example, recent evidence suggests microbial grazers, resource availability, and plant roots each impact on microbial community stability. We explore these hypotheses by offering three vignettes of published data that that we re-analyzed. Our results show that community measures of the relative abundance of r- and K-strategists, as well as environmental properties like resource availability and the abundance and diversity of higher trophic levels, can contribute to explaining the response of microbial community composition to climate change-related disturbances. However, further investigation and experimental validation is necessary to directly test these hypotheses across a wide range of soil ecosystems.

  9. Use of predictions in temperature control in buildings: A passive climate system application. Doctoral thesis

    Energy Technology Data Exchange (ETDEWEB)

    Lute, P.J.

    1992-01-01

    The thesis consists of two parts. The first part is a general part about predictive control in the indoor climate field. The second part deals with the control system implementation in the passive indoor climate system. The fundamentals, general principles and mechanisms of the class of predictive controllers and control strategies with a linear objective function are described in chapter 2. Chapter 3 deals with the typical characteristics of the indoor and outdoor climate, that have to be incorporated in a predictive control system to make it a successful and robust predictive indoor climate control system. A general scheme for a predictive indoor climate system, that has self-learning features, is described in Chapter 4. Chapter 5 introduces the passive indoor climate system to which a predictive control strategy is applied. Finally, in Chapter 6, a test facility for passive climate systems, referred to as the TU Delft test cell, is described.

  10. Quantifying the Impacts of Environmental Factors on Vegetation Dynamics over Climatic and Management Gradients of Central Asia

    Directory of Open Access Journals (Sweden)

    Olena Dubovyk

    2016-07-01

    Full Text Available Currently there is a lack of quantitative information regarding the driving factors of vegetation dynamics in post-Soviet Central Asia. Insufficient knowledge also exists concerning vegetation variability across sub-humid to arid climatic gradients as well as vegetation response to different land uses, from natural rangelands to intensively irrigated croplands. In this study, we analyzed the environmental drivers of vegetation dynamics in five Central Asian countries by coupling key vegetation parameter “overall greenness” derived from Moderate Resolution Imaging Spectroradiometer (MODIS Normalized Difference Vegetation Index (NDVI time series data, with its possible factors across various management and climatic gradients. We developed nine generalized least-squares random effect (GLS-RE models to analyze the relative impact of environmental factors on vegetation dynamics. The obtained results quantitatively indicated the extensive control of climatic factors on managed and unmanaged vegetation cover across Central Asia. The most diverse vegetation dynamics response to climatic variables was observed for “intensively managed irrigated croplands”. Almost no differences in response to these variables were detected for managed non-irrigated vegetation and unmanaged (natural vegetation across all countries. Natural vegetation and rainfed non-irrigated crop dynamics were principally associated with temperature and precipitation parameters. Variables related to temperature had the greatest relative effect on irrigated croplands and on vegetation cover within the mountainous zone. Further research should focus on incorporating the socio-economic factors discussed here in a similar analysis.

  11. Socioeconomic Factors and Asthma Control in Children

    Science.gov (United States)

    Cope, Shannon F.; Ungar, Wendy J.; Glazier, Richard H.

    2016-01-01

    Summary Objectives The objective of this study was to evaluate the association between socioeconomic factors and asthma control in children, as defined by the Canadian Pediatric Asthma Consensus Guidelines. Patients and Methods Cross-sectional data from a completed study of 879 asthmatic children between the ages of 1 and 18 residing in the Greater Toronto Area were used. The database included data on demographics, health status, asthma control, and health-related quality of life. Stepwise forward modeling multiple regression was used to investigate the impact of socioeconomic status on asthma control, based on six control parameters from the 2003 Canadian Pediatric Asthma Consensus Guidelines. Results Only 11% of patients met the requirements for acceptable control, while 20% had intermediate control, and 69% had unacceptable asthma control. Children from families in lower income adequacy levels had poorer control. Conclusions Disparities in asthma control between children from families of different socio-economic strata persist, even with adjustment for utilization of primary care services and use of controller medications. PMID:18615669

  12. The sensitivity of NPP to climate controls in northern China estimated by CLM model coupled with RS and GIS technology

    Science.gov (United States)

    Gao, Zhiqiang; Gao, Wei; Slusser, James R.; Pan, Xiaoling; Ma, Yingjun

    2003-07-01

    The continuing rise in atmospheric CO2 is considered as a main cause of the future changes in global climate. Predicted climate changes include an increase in mean annual air temperature and alterations in precipitation pattern and cloud cover. Net primary productivity (NPP) measures products of major economic and social importance, such as agricultural crop yield and forest production. It is important to understand the response of vegetation to the possible climate changes. While the Global NPP is hard to be measured directly, its global spatial and temporal dynamics can be investigated by a combination of ecosystem process modeling and monitoring by remote sensing (RS). NPP has been linked to climatic patterns by approaches ranging from simple correlations to sophisticated simulation models. This study was conducted in a range where the productivity and climate exist along an east-west transect in northern China. We used modified Common Land Surface Model (CLM) to simulate the NPP combined with satellite data and assessed the response of NPP under different climate change controls with different land surface vegetation types in study areas. The feasibility of the CLM model was tested and parameterized based on the ecological characteristics. The response of NPP to increased temperature was more sensitive to the doubled CO2 climate because the temperature is the limited factor to vegetation growth in study areas. The responses of NPP to different climate controls were also influenced by different vegetation types and ecological characteristics.

  13. Rconfigurable adaptive fuzzy fault-hiding control for greenhouse climate control system

    DEFF Research Database (Denmark)

    Hameed, Ibrahim; El-Madbouly, E I; Abdo, M I

    2016-01-01

    Modern greenhouses are equipped with different components for providing a comfortable climate for plant growth. A component malfunction may result in loss of production. Therefore, it is desirable to design a control system, which is stable, and is able to provide an acceptable degraded performance...... even in the faulty case. In this paper, an active fault tolerant control scheme to compensate for actuator and/or sensor faults in the greenhouse climate system is designed. The control system consists of a sensitive and reliable Fault Detection and Diagnosis (FDD) mechanism for different types...... of faults in presence of system disturbances and a robust reconfigurable control design based on fault-hiding principal in which the fault is hidden from the nominal controller and the fault effects are compensated. In this approach, a set of virtual actuators and virtual sensors are used to guarantee...

  14. A new numerical framework for simulating the control of weather and climate on the evolution of soil-mantled hillslopes

    Science.gov (United States)

    Bovy, Benoît; Braun, Jean; Demoulin, Alain

    2016-06-01

    We present a new numerical framework for simulating short to long-term hillslope evolution. This modeling framework, to which we have given the name CLICHE (CLImate Control on Hillslope Evolution), aims to better capture the control of climate on soil dynamics. It allows the use of realistic forcing that involves, through a specific time discretization scheme, the variability of both the temperature and precipitation at time scales ranging from the daily rainfall events to the climatic oscillations of the Quaternary, also including seasonal variability. Two simple models of soil temperature and soil water balance permit the link between the climatic inputs and derived quantities that take part in the computation of the soil flux, such as the surface water discharge and the depth of the non-frozen soil layer. Using this framework together with a multi-process parameterization of soil transport, we apply an original method to calculate hillslope effective diffusivity as a function of climate. This allows us to demonstrate the ability of the model to simulate observed rates of hillslope erosion under different climates (cold and temperate) with a single set of parameter values. Numerical experiments furthermore suggest a potential high peak of sediment transport on hillslopes during the glacial-interglacial transitions of the Quaternary. We finally discuss the need to improve the parameterization of the soil production and transport processes in order to explicitly account for other key controlling factors that are also climate-sensitive, such as biological activity.

  15. Climate vs. soil factors in local adaptation of two common plant species

    NARCIS (Netherlands)

    Macel, M.; Lawson, C.S.; Mortimer, S.R.; Smilauerova, M.; Bischoff, A.; Crémieux, L.; Dolezal, J.; Edwards, A.R.; Lanta, V.; Bezemer, T.M.; Putten, van der W.H.; Igual, J.M.; Rodriguez-Barrueco, C.; Müller-Schärer, H.; Steinger, T.

    2007-01-01

    Evolutionary theory suggests that divergent natural selection in heterogeneous environments can result in locally adapted plant genotypes. To understand local adaptation it is important to study the ecological factors responsible for divergent selection. At a continental scale, variation in climate

  16. Key factors affecting urban runoff pollution under cold climatic conditions

    Science.gov (United States)

    Valtanen, Marjo; Sillanpää, Nora; Setälä, Heikki

    2015-10-01

    Urban runoff contains various pollutants and has the potential of deteriorating the quality of aquatic ecosystems. In this study our objective is to shed light on the factors that control the runoff water quality in urbanized catchments. The effects of runoff event characteristics, land use type and catchment imperviousness on event mass loads (EML) and event mean concentrations (EMC) were studied during warm and cold periods in three study catchments (6.1, 6.5 and 12.6 ha in size) in the city of Lahti, Finland. Runoff and rainfall were measured continuously for two years at each catchment. Runoff samples were taken for total nutrients (tot-P and tot-N), total suspended solids (TSS), heavy metals (Zn, Cr, Al, Co, Ni, Cu, Pb, Mn) and total organic carbon (TOC). Stepwise multiple linear regression analysis (SMLR) was used to identify general relationships between the following variables: event water quality, runoff event characteristics and catchment characteristics. In general, the studied variables explained 50-90% of the EMLs but only 30-60% of the EMCs, with runoff duration having an important role in most of the SMLR models. Mean runoff intensity or peak flow was also often included in the runoff quality models. Yet, the importance (being the first, second or third best) and role (negative or positive impact) of the explanatory variables varied between the cold and warm period. Land use type often explained cold period concentrations, but imperviousness alone explained EMCs weakly. As for EMLs, the influence of imperviousness and/or land use was season and pollutant dependent. The study suggests that pollutant loads can be - throughout the year - adequately predicted by runoff characteristics given that seasonal differences are taken into account. Although pollutant concentrations were sensitive to variation in seasonal and catchment conditions as well, the accurate estimation of EMCs would require a more complete set of explanatory factors than used in this

  17. Impact on Organizational Climate trough Organizational Culture factors. Case Study of Latvia and Lithuania

    OpenAIRE

    Iljins, Juris; Skvarciany, Viktorija; Gaile-Sarkane, Elīna

    2015-01-01

    Purpose of the article: The purpose of this paper is to investigate the impact of organizational culture on organizational climate in process of change. For solving this problem, it is necessary to identify the main factors of organizational culture in the change process. After exploring the impact of organizational culture on organizational climate through distinguished culture’s factors, article examines how changes can be processed in different cultural environments. Methodology. The resea...

  18. Transcription factor PIF4 controls the thermosensory activation of flowering

    KAUST Repository

    Kumar, S. Vinod

    2012-03-21

    Plant growth and development are strongly affected by small differences in temperature. Current climate change has already altered global plant phenology and distribution, and projected increases in temperature pose a significant challenge to agriculture. Despite the important role of temperature on plant development, the underlying pathways are unknown. It has previously been shown that thermal acceleration of flowering is dependent on the florigen, FLOWERING LOCUS T (FT). How this occurs is, however, not understood, because the major pathway known to upregulate FT, the photoperiod pathway, is not required for thermal acceleration of flowering. Here we demonstrate a direct mechanism by which increasing temperature causes the bHLH transcription factor PHYTOCHROME INTERACTING FACTOR4 (PIF4) to activate FT. Our findings provide a new understanding of how plants control their timing of reproduction in response to temperature. Flowering time is an important trait in crops as well as affecting the life cycles of pollinator species. A molecular understanding of how temperature affects flowering will be important for mitigating the effects of climate change. © 2012 Macmillan Publishers Limited. All rights reserved.

  19. Dominant climatic factors driving annual runoff changes at the catchment scale across China

    Science.gov (United States)

    Huang, Zhongwei; Yang, Hanbo; Yang, Dawen

    2016-07-01

    With global climate changes intensifying, the hydrological response to climate changes has attracted more attention. It is beneficial not only for hydrology and ecology but also for water resource planning and management to understand the impact of climate change on runoff. In addition, there are large spatial variations in climate type and geographic characteristics across China. To gain a better understanding of the spatial variation of the response of runoff to changes in climatic factors and to detect the dominant climatic factors driving changes in annual runoff, we chose the climate elasticity method proposed by Yang and Yang (2011). It is shown that, in most catchments of China, increasing air temperature and relative humidity have negative impacts on runoff, while declining net radiation and wind speed have positive impacts on runoff, which slow the overall decline in runoff. The dominant climatic factors driving annual runoff are precipitation in most parts of China, net radiation mainly in some catchments of southern China, air temperature and wind speed mainly in some catchments in northern China.

  20. Effects of climate factors on the height increment of poplar protection forest in the riverbank field

    Institute of Scientific and Technical Information of China (English)

    LIHai-mei; HEXing-yuan; WANGKui-ling

    2004-01-01

    Based on the data of stand investigation and stem analysis, the effects of climate factors on the poplar protection forest increment in the riverbank field of the Dalinghe and Xiaolinghe rivers of Liaoning Province, China were studied by stepwise regression procedure and grey system theories and methods. A regression model reflecting the correlation between the height increment of poplar protection forest and climatic factors was developed. The order of grey relevance for the effect of climatic factors on the height increment of poplar protection forest is" light>water>heat, and it could be interpreted that the poplar increment was mainly influenced by light factor, water factor, and heat factor. This result will provide scientific basis for the intensive cultivation and regeneration of the poplar protection forest in riverbank field in similar regions in China.

  1. Climate factors play a limited role for past adaptation strategies in West Africa

    DEFF Research Database (Denmark)

    Mertz, Ole; Mbow, Cheikh; Nielsen, Jonas Østergaard;

    2010-01-01

    The Sudano-Sahelian zone of West Africa has experienced recurrent droughts since the mid-1970s and today there is considerable concern for how this region will be able to adapt to future climate change. To develop well targeted adaptation strategies, the relative importance of climate factors...... as drivers of land use and livelihood change need to be better understood. Based on the perceptions of 1249 households in five countries across an annual rainfall gradient of 400-900 mm, we provide an estimate of the relative weight of climate factors as drivers of changes in rural households during the past...

  2. The Influence of Safety Training on Safety Climate Factors in a Construction Site

    OpenAIRE

    MohammadJavad Jafari; Mehdi Gharari; Mohtasham Ghafari; Leila Omidi; Saba Kalantari; GolamReza Asadolah-Fardi

    2015-01-01

     Safety issues have always been put forward as one of the major problems and primary concerns in construction industries in many countries. This paper will focus on the impact of safety training on safety climate and its relevant factors in two sites of a construction firm. The Health and Safety Executive (HSE) guide to safety climate tool that had been validated in Iran was used to determine the impacts of safety training on safety climate and its relevant factors. For this purpose, 347 work...

  3. The role of climate and socioeconomic factors on the spatiotemporal variability of cholera in Nigeria

    Science.gov (United States)

    Abdussalam, Auwal; Thornes, John; Leckebusch, Gregor

    2015-04-01

    Nigeria has a number of climate-sensitive infectious diseases; one of the most important of these diseases that remains a threat to public health is cholera. This study investigates the influences of both meteorological and socioeconomic factors on the spatiotemporal variability of cholera in Nigeria. A stepwise multiple regression models are used to estimate the influence of the year-to-year variations of cholera cases and deaths for individual states in the country and as well for three groups of states that are classified based on annual rainfall amount. Specifically, seasonal mean maximum and minimum temperatures and annual rainfall totals were analysed with annual aggregate count of cholera cases and deaths, taking into account of the socioeconomic factors that are potentially enhancing vulnerability such as: absolute poverty, adult literacy, access to pipe borne water and population density. Result reveals that the most important explanatory meteorological and socioeconomic variables in explaining the spatiotemporal variability of the disease are rainfall totals, seasonal mean maximum temperature, absolute poverty, and accessibility to pipe borne water. The influences of socioeconomic factors appeared to be more pronounced in the northern part of the country, and vice-versa in the case of meteorological factors. Also, cross validated models output suggests a strong possibility of disease prediction, which will help authorities to put effective control measures in place which depend on prevention, and or efficient response.

  4. Studying the Relationship Between Climatic Factors and Cotton Production by Different Applied Methods

    Directory of Open Access Journals (Sweden)

    Zakaria M. Sawan

    2013-11-01

    Full Text Available This study investigates the statistical relationship between climatic variables and aspects of cotton production (G. barbadense, and the effects of climatic factors prevailing prior to flowering or subsequent to boll setting on flower and boll production and retention in cotton. Also, the study covers the predicted effects of climatic factors during convenient intervals (in days on cotton flower and boll production compared with daily observation. Further, cotton flower and boll production as affected by climatic factors and soil moisture status has been considered. Evaporation, sunshine duration, relative humidity , surface soil temperature at 1800 h, and maximum air temperature are the important climatic factors that significantly affect flower and boll production. The least important variables were found to be surface soil temperature at 0600 h and minimum temperature. The five-day interval was found to be more adequately and sensibly related to yield parameters. Evaporation, minimum humidity and sunshine duration were the most effective climatic factors during preceding and succeeding periods on boll production and retention. There was a negative correlation between flower and boll production and either evaporation or sunshine duration, while that correlation with minimum relative humidity was positive. The soil moisture status showed low and in significant correlation with flower and boll production. Higher minimum relative humidity, short period of sunshine duration, and low temperatures enhanced flower and boll formation.

  5. Association between climate factors and diarrhoea in a Mekong Delta area

    Science.gov (United States)

    Phung, Dung; Huang, Cunrui; Rutherford, Shannon; Chu, Cordia; Wang, Xiaoming; Nguyen, Minh; Nguyen, Nga Huy; Manh, Cuong Do; Nguyen, Trung Hieu

    2015-09-01

    The Mekong Delta is vulnerable to changes in climate and hydrological events which alter environmental conditions, resulting in increased risk of waterborne diseases. Research exploring the association between climate factors and diarrhoea, the most frequent waterborne disease in Mekong Delta region, is sparse. This study evaluated the climate-diarrhoea association in Can Tho city, a typical Mekong Delta area in Vietnam. Climate data (temperature, relative humidity, and rainfall) were obtained from the Southern Regional Hydro-Meteorological Centre, and weekly counts of diarrhoea visits were obtained from Can Tho Preventive Medicine Centre from 2004 to 2011. Analysis of climate and health variables was carried out using spline function to adjust for seasonal and long-term trends of variables. A distributed lag model was used to investigate possible delayed effects of climate variables on diarrhoea (considering 0-4 week lag periods), then the multivariate Poisson regression was used to examine any potential association between climate factors and diarrhoea. The results indicated that the diarrhoea incidence peaked within the period August-October annually. Significant positive associations were found between increased diarrhoea and high temperature at 4 weeks prior to the date of hospital visits (IRR = 1.07; 95 % CI = 1.04-1.08), high relative humidity (IRR = 1.13; 95 % CI = 1.12-1.15) and high (>90th percentile) cumulative rainfall (IRR = 1.05; 95 % CI = 1.05-1.08). The association between climate factors and diarrhoea was stronger in rural than urban areas. These findings in the context of the projected changes of climate conditions suggest that climate change will have important implications for residential health in Mekong Delta region.

  6. An Agent-based Extensible Climate Control System for Sustainable Greenhouse Production

    DEFF Research Database (Denmark)

    Sørensen, Jan Corfixen; Jørgensen, Bo Nørregaard; Klein, Mark;

    2011-01-01

    The slow adoption pace of new control strategies for sustainable greenhouse climate control by industrial growers is mainly due to the complexity of identifying and resolving potentially conflicting climate control requirements. In this paper, we present a multi-agent-based climate control system....... Negotiation is done using a novel multi-issue negotiation protocol that uses a generic algorithm to find an optimized solution within the search space. The Multi-Agent control system has been empirically evaluated in an ornamental floriculture research facility in Denmark. The evaluation showed...... that it is realistic to implement the climate control requirements as individual agents, thereby opening greenhouse climate control systems for integration of independently produced control strategies....

  7. Influence of climate factors on Vibrio cholerae dynamics in the Pearl River estuary, South China.

    Science.gov (United States)

    Yue, Yujuan; Gong, Jianhua; Wang, Duochun; Kan, Biao; Li, Baisheng; Ke, Changwen

    2014-06-01

    Current research has seldom focused on the quantitative relationships between Vibrio cholerae (V. cholerae) and climate factors owing to the complexities and high cost of field observation in the aquatic environment. This study has focused on the relationships between V. cholerae and climate factors based on linear regression method and data partition method. Data gathered from 2008 to 2009 in the Pearl River estuary, South China, were adopted. Positive rate of V. cholerae was correlated closely with monthly climate factors of water temperature and air temperature, respectively in 2009. Quarterly data analysis from 2008 to 2009 showed that there existed seasonal characteristic for V. cholerae. Positive rate of V. cholerae was correlated positively with quarterly climate factors of land surface temperature, pH, water temperature, air temperature and rainfall, respectively and negatively with quarterly air pressure. Partition data analysis in 2009 showed that there existed geography region characteristic for V. cholerae. V. cholerae dynamics was closely correlated to climate factors in the downstream area. However, it was more greatly affected by human geography factors in the urban area. Positive annual rate of V. cholerae was higher in the downstream area than in the urban area both in 2008 and 2009. At last, a cellular automaton model was used to simulate V. cholerae diffusion downstream, and the distribution of V. cholerae obtained from this model was similar to that obtained from the field observations.

  8. Elevational and Latitudinal Gradient Sites Enable Phenology Controls and Climate Change Detection

    Science.gov (United States)

    Losleben, M. V.; Weltzin, J. F.; Billick, I.; Jones, D.

    2008-12-01

    Phenology is the study of the timing of recurring biological phases, the causes of their timing with regard to biotic and abiotic forces, and the interrelation among phases of the same or different species. Although phenology is a far-reaching component of environmental science, it is poorly understood relative to other ecological patterns and processes. For example, it is unclear how climatic attributes affect the phenology of different organisms, and how those attributes vary in importance on different spatial and temporal scales. We know phenology affects the abundance and diversity of organisms, and their function and interactions in the environment, especially their effects on fluxes in water, energy, and chemical elements at various scales. With sufficient observations and understanding, phenology can be used as a predictor for other processes and variables of importance at local to global scales, and phenology could drive a variety of ecological forecast models with both scientific and practical applications. Integration of spatially-extensive phenological data and models with both short and long-term climatic forecasts offer a powerful agent for human adaptation to ongoing and future climate change. To fully utilize the value of phenology, not only more observations at more locations are needed, but also linkages between climatic factors and phenology must be more firmly established through linked direct observations and remotely sensed (Landscape Phenology or LSP) measurements with climatic factors. Sites along elevational gradients over a range of latitudes provide this opportunity. Elevational gradients present the phenological observational efficiency of compressed ecosystem transitions, and through climatic matching of sites, latitudinal range presents opportunities to control for additional abiotic factors such as day length, seasonal variability, storm track, and atmospheric chemistry. These sites also provide excellent platforms to advance new, and

  9. Safety factor profile control in a tokamak

    CERN Document Server

    Bribiesca Argomedo, Federico; Prieur, Christophe

    2014-01-01

    Control of the Safety Factor Profile in a Tokamak uses Lyapunov techniques to address a challenging problem for which even the simplest physically relevant models are represented by nonlinear, time-dependent, partial differential equations (PDEs). This is because of the  spatiotemporal dynamics of transport phenomena (magnetic flux, heat, densities, etc.) in the anisotropic plasma medium. Robustness considerations are ubiquitous in the analysis and control design since direct measurements on the magnetic flux are impossible (its estimation relies on virtual sensors) and large uncertainties remain in the coupling between the plasma particles and the radio-frequency waves (distributed inputs). The Brief begins with a presentation of the reference dynamical model and continues by developing a Lyapunov function for the discretized system (in a polytopic linear-parameter-varying formulation). The limitations of this finite-dimensional approach motivate new developments in the infinite-dimensional framework. The t...

  10. Simulation of Greenhouse Climate Monitoring and Control with Wireless Sensor Network and Event-Based Control

    Directory of Open Access Journals (Sweden)

    Andrzej Pawlowski

    2009-01-01

    Full Text Available Monitoring and control of the greenhouse environment play a decisive role in greenhouse production processes. Assurance of optimal climate conditions has a direct influence on crop growth performance, but it usually increases the required equipment cost. Traditionally, greenhouse installations have required a great effort to connect and distribute all the sensors and data acquisition systems. These installations need many data and power wires to be distributed along the greenhouses, making the system complex and expensive. For this reason, and others such as unavailability of distributed actuators, only individual sensors are usually located in a fixed point that is selected as representative of the overall greenhouse dynamics. On the other hand, the actuation system in greenhouses is usually composed by mechanical devices controlled by relays, being desirable to reduce the number of commutations of the control signals from security and economical point of views. Therefore, and in order to face these drawbacks, this paper describes how the greenhouse climate control can be represented as an event-based system in combination with wireless sensor networks, where low-frequency dynamics variables have to be controlled and control actions are mainly calculated against events produced by external disturbances. The proposed control system allows saving costs related with wear minimization and prolonging the actuator life, but keeping promising performance results. Analysis and conclusions are given by means of simulation results.

  11. Computer Controlled Portable Greenhouse Climate Control System for Enhanced Energy Efficiency

    Science.gov (United States)

    Datsenko, Anthony; Myer, Steve; Petties, Albert; Hustek, Ryan; Thompson, Mark

    2010-04-01

    This paper discusses a student project at Kettering University focusing on the design and construction of an energy efficient greenhouse climate control system. In order to maintain acceptable temperatures and stabilize temperature fluctuations in a portable plastic greenhouse economically, a computer controlled climate control system was developed to capture and store thermal energy incident on the structure during daylight periods and release the stored thermal energy during dark periods. The thermal storage mass for the greenhouse system consisted of a water filled base unit. The heat exchanger consisted of a system of PVC tubing. The control system used a programmable LabView computer interface to meet functional specifications that minimized temperature fluctuations and recorded data during operation. The greenhouse was a portable sized unit with a 5' x 5' footprint. Control input sensors were temperature, water level, and humidity sensors and output control devices were fan actuating relays and water fill solenoid valves. A Graphical User Interface was developed to monitor the system, set control parameters, and to provide programmable data recording times and intervals.

  12. THE IMPACT OF STRUCTURAL, PETROGRAPHIC AND CLIMATIC FACTORS ON THE SLOPE STABILITY IN THE OPEN CAST MINE OF GRADNA

    Directory of Open Access Journals (Sweden)

    Ivan Tomašić

    1992-12-01

    Full Text Available This paper presents an analysis of a complexity of interrelated structural, petrologic and climatic factors that considerably affect the instabilities in the open cast mine of Gradna, near Samobor. The instabilities provoke the slope failures such as slides and slumps of rock material. During the protracted periodical investigations, the relationship among the factors of regional geology, tectonics, structural geology, petrography, engineering geology, rock mechanics and the rock mining technology was observed in the area. The local control of hydrogeologic properties, as well as climatic fluctuations of temperature and precipitation on the slope stability, was also recognized. It turned out that the structural relationships, characteristic of the manifold cataclased dolomite, stimulated the development of local instabilities, particularly during the period of low temperatures affecting the process of ground-water accumulation. When the temperatures are worm, the ground-water circulation is slow, exerting only the small-scale influence on the local instabilities (the paper is published in Croatian.

  13. Abrupt Holocene climate change as an important factor for human migration in West Greenland

    OpenAIRE

    D’Andrea, William J.; Huang, Yongsong; Sherilyn C Fritz; Anderson, N. John

    2011-01-01

    West Greenland has had multiple episodes of human colonization and cultural transitions over the past 4,500 y. However, the explanations for these large-scale human migrations are varied, including climatic factors, resistance to adaptation, economic marginalization, mercantile exploration, and hostile neighborhood interactions. Evaluating the potential role of climate change is complicated by the lack of quantitative paleoclimate reconstructions near settlement areas and by the relative stab...

  14. Factors predicting team climate, and its relationship with quality of care in general practice

    OpenAIRE

    Eccles Martin P; Goh Teik T; Steen Nick

    2009-01-01

    Abstract Background Quality of care in general practice may be affected by the team climate perceived by its health and non-health professionals. Better team working is thought to lead to higher effectiveness and quality of care. However, there is limited evidence available on what affects team functioning and its relationship with quality of care in general practice. This study aimed to explore individual and practice factors that were associated with team climate, and to explore the relatio...

  15. Farmers' Perceived Risks of Climate Change and Influencing Factors: A Study in the Mekong Delta, Vietnam

    Science.gov (United States)

    Le Dang, Hoa; Li, Elton; Nuberg, Ian; Bruwer, Johan

    2014-08-01

    Many countries are confronting climate change that threatens agricultural production and farmers' lives. Farmers' perceived risks of climate change and factors influencing those perceived risks are critical to their adaptive behavior and well-planned adaptation strategies. However, there is limited understanding of these issues. In this paper, we attempt to quantitatively measure farmers' perceived risks of climate change and explore the influences of risk experience, information, belief in climate change, and trust in public adaptation to those perceived risks. Data are from structured interviews with 598 farmers in the Mekong Delta. The study shows that perceived risks to production, physical health, and income dimensions receive greater priority while farmers pay less attention to risks to happiness and social relationships. Experiences of the events that can be attributed to climate change increase farmers' perceived risks. Information variables can increase or decrease perceived risks, depending on the sources of information. Farmers who believe that climate change is actually happening and influencing their family's lives, perceive higher risks in most dimensions. Farmers who think that climate change is not their concern but the government's, perceive lower risks to physical health, finance, and production. As to trust in public adaptation, farmers who believe that public adaptive measures are well co-ordinated, perceive lower risks to production and psychology. Interestingly, those who believe that the disaster warning system is working well, perceive higher risks to finance, production, and social relationships. Further attention is suggested for the quality, timing, and channels of information about climate change and adaptation.

  16. Climatic change controls productivity variation in global grasslands

    OpenAIRE

    Qingzhu Gao; Wenquan Zhu; Schwartz, Mark W.; Hasbagan Ganjurjav; Yunfan Wan; Xiaobo Qin; Xin Ma; Williamson, Matthew A.; Yue Li

    2016-01-01

    Detection and identification of the impacts of climate change on ecosystems have been core issues in climate change research in recent years. In this study, we compared average annual values of the normalized difference vegetation index (NDVI) with theoretical net primary productivity (NPP) values based on temperature and precipitation to determine the effect of historic climate change on global grassland productivity from 1982 to 2011. Comparison of trends in actual productivity (NDVI) with ...

  17. The Relationship among Antibiotic Consumption, Socioeconomic Factors and Climatic Conditions

    Directory of Open Access Journals (Sweden)

    Fawziah Marra

    2010-01-01

    Full Text Available BACKGROUND: Antibiotic consumption in human populations is one of the factors responsible for the emergence of resistant organisms. It is important to track population-based data on an ongoing basis, and to explore the determinants of regional variation in antibiotic consumption.

  18. Impact of CO2 and climate on Last Glacial Maximum vegetation – a factor separation

    Directory of Open Access Journals (Sweden)

    T. Raddatz

    2012-11-01

    Full Text Available Differences between glacial and pre-industrial potential vegetation patterns can conceptually be attributed to two factors: firstly to differences in the climate, caused by a strong increase in ice masses and the radiative effect of lower greenhouse gas concentrations, and secondly to differences in the ecophysiological effect of lower glacial atmospheric CO2 concentrations. The synergy emerging from these effects when operating simultaneously can be interpreted as sensitivity of the effect of enhancing physiologically available CO2 on shifting vegetation to climate warming. Alternatively and equally valid, it can be viewed as sensitivity of climatically induced vegetation changes to differences in physiologically available CO2. A first complete factor separation based on simulations with the MPI Earth System Model indicates that the pure climate effect mainly leads to a contraction or a shift in vegetation patterns when comparing glacial with pre-industrial simulation vegetation patterns. Globally, a reduction in fractional coverage of most plant functional types is seen – except for raingreen shrubs which strongly benefit from the colder and drier climate. The ecophysiological effect of CO2 appears to be stronger than the pure climate contribution for many plant functional types – in line with previous simulations. The ecophysiological effect of lower CO2 mainly yields a reduction in fractional coverage, a thinning of vegetation and a strong reduction in net primary production. The synergy appears to be as strong as each of the pure contributions locally. For tropical evergreen trees, the synergy appears strong also on global average. Hence this modelling study suggests that for tropical forests, an increase in CO2 has, on average, a stronger ecophysiological effect in warmer climate than in glacial climate. Alternatively, areal differences in tropical forests induced by climate warming can, on average, be expected to be larger with

  19. Climate controls the distribution of a widespread invasive species: Implications for future range expansion

    Science.gov (United States)

    McDowell, W.G.; Benson, A.J.; Byers, J.E.

    2014-01-01

    1. Two dominant drivers of species distributions are climate and habitat, both of which are changing rapidly. Understanding the relative importance of variables that can control distributions is critical, especially for invasive species that may spread rapidly and have strong effects on ecosystems. 2. Here, we examine the relative importance of climate and habitat variables in controlling the distribution of the widespread invasive freshwater clam Corbicula fluminea, and we model its future distribution under a suite of climate scenarios using logistic regression and maximum entropy modelling (MaxEnt). 3. Logistic regression identified climate variables as more important than habitat variables in controlling Corbicula distribution. MaxEnt modelling predicted Corbicula's range expansion westward and northward to occupy half of the contiguous United States. By 2080, Corbicula's potential range will expand 25–32%, with more than half of the continental United States being climatically suitable. 4. Our combination of multiple approaches has revealed the importance of climate over habitat in controlling Corbicula's distribution and validates the climate-only MaxEnt model, which can readily examine the consequences of future climate projections. 5. Given the strong influence of climate variables on Corbicula's distribution, as well as Corbicula's ability to disperse quickly and over long distances, Corbicula is poised to expand into New England and the northern Midwest of the United States. Thus, the direct effects of climate change will probably be compounded by the addition of Corbicula and its own influences on ecosystem function.

  20. Spatial Diffusion of Influenza Outbreak-Related Climate Factors in Chiang Mai Province, Thailand

    Directory of Open Access Journals (Sweden)

    Marc Souris

    2012-10-01

    Full Text Available Influenza is one of the most important leading causes of respiratory illness in the countries located in the tropical areas of South East Asia and Thailand. In this study the climate factors associated with influenza incidence in Chiang Mai Province, Northern Thailand, were investigated. Identification of factors responsible for influenza outbreaks and the mapping of potential risk areas in Chiang Mai are long overdue. This work examines the association between yearly climate patterns between 2001 and 2008 and influenza outbreaks in the Chiang Mai Province. The climatic factors included the amount of rainfall, percent of rainy days, relative humidity, maximum, minimum temperatures and temperature difference. The study develops a statistical analysis to quantitatively assess the relationship between climate and influenza outbreaks and then evaluate its suitability for predicting influenza outbreaks. A multiple linear regression technique was used to fit the statistical model. The Inverse Distance Weighted (IDW interpolation and Geographic Information System (GIS techniques were used in mapping the spatial diffusion of influenza risk zones. The results show that there is a significance correlation between influenza outbreaks and climate factors for the majority of the studied area. A statistical analysis was conducted to assess the validity of the model comparing model outputs and actual outbreaks.

  1. "What Controls the Structure and Stability of the Ocean Meridional Overturning Circulation: Implications for Abrupt Climate Change?"

    Energy Technology Data Exchange (ETDEWEB)

    Fedorov, Alexey [Yale University

    2013-11-23

    The central goal of this research project is to understand the properties of the ocean meridional overturning circulation (MOC) – a topic critical for understanding climate variability and stability on a variety of timescales (from decadal to centennial and longer). Specifically, we have explored various factors that control the MOC stability and decadal variability in the Atlantic and the ocean thermal structure in general, including the possibility abrupt climate change. We have also continued efforts on improving the performance of coupled ocean-atmosphere GCMs.

  2. Effects of Climate and Rodent Factors on Hemorrhagic Fever with Renal Syndrome in Chongqing, China, 1997-2008.

    Directory of Open Access Journals (Sweden)

    Yuntao Bai

    Full Text Available China has the highest global incidence of hemorrhagic fever with renal syndrome (HFRS, constituting 90% of the cases in the world. Chongqing, located in the Three Gorges Reservoir Region, has been experiencing differences in the occurrence of HFRS from 1997 to 2008. The current study was designed to explore the effects of climate and rodent factors on the transmission of HFRS in Chongqing. Data on monthly HFRS cases, rodent strains, and climatic factors were collected from 1997 to 2008. Spatio-temporal analysis indicated that most HFRS cases were clustered in central Chongqing and that the incidence of HFRS decreased from 1997 to 2008. Poisson regression models showed that temperature (with lagged months of 0 and 5 and rainfall (with 2 lagged months were key climatic factors contributing to the transmission of HFRS. A zero-inflated negative binomial model revealed that rodent density was also significantly associated with the occurrence of HFRS in the Changshou district. The monthly trend in HFRS incidence was positively associated with rodent density and rainfall and negatively associated with temperature. Possible mechanisms are proposed through which construction of the dam influenced the incidence of HFRS in Chongqing. The findings of this study may contribute to the development of early warning systems for the control and prevention of HFRS in the Three Gorges Reservoir Region.

  3. A Fast Version of LASG/IAP Climate System Model and Its 1000-year Control Integration

    Institute of Scientific and Technical Information of China (English)

    ZHOU Tianjun; WU Bo; WEN Xinyu; LI Lijuan; WANG Bin

    2008-01-01

    A fast version of the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geo- physical Fluid Dynamics (LASG)/Institute of Atmospheric Physics (IAP) climate system model is briefly documented. The fast coupled model employs a low resolution version of the atmospheric component Grid Atmospheric Model of IAP/LASG (GAMIL), with the other parts of the model, namely an oceanic com- ponent LASG/IAP Climate Ocean Model (LICOM), land component Common Land Model (CLM), and sea ice component from National Center for Atmospheric Research Community Climate System Model (NCAR CCSM2), as the same as in the standard version of LASG/IAP Flexible Global Ocean Atmosphere Land System model (FGOALS_g). The parameterizatious of physical and dynamical processes of the at- mospheric component in the fast version are identical to the standard version, although some parameter values are different. However, by virtue of reduced horizontal resolution and increased time-step of the most time-consuming atmospheric component, it runs faster by a factor of 3 and can serve as a useful tool for long- term and large-ensemble integrations. A 1000-year control simulation of the present-day climate has been completed without flux adjustments. The final 600 years of this simulation has virtually no trends in global mean sea surface temperatures and is recommended for internal variability studies. Several aspects of the control simulation's mean climate and variability axe evaluated against the observational or reanalysis data. The strengths and weaknesses of the control simulation are evaluated. The mean atmospheric circulation is well simulated, except in high latitudes. The Asian-Australian monsoonal meridional cell shows realistic features, however, an artificial rainfall center is located to the eastern periphery of the Tibetan Plateau persists throughout the year. The mean bias of SST resembles that of the standard version, appearing as a "double ITCZ" (Inter

  4. Geographical distribution for malignant neoplasm of the pancreas in relation to selected climatic factors in Japan

    Directory of Open Access Journals (Sweden)

    Okada Masafumi

    2007-07-01

    Full Text Available Abstract Background Malignant neoplasm of the pancreas has become one of the leading causes of death from malignant neoplasm in Japan (the 5th in 2003. Although smoking is believed to be a risk factor, other risk factors remain unclear. Mortality from malignant neoplasm of the pancreas tends to be higher in northern Japan and in northern European countries. A recent study reported that standardized mortality ratios (SMRs for malignant neoplasm of the pancreas were negatively correlated to global solar radiation level. People residing in regions with lower solar radiation and lower temperatures may be at higher risk of development of malignant neoplasm of the pancreas. Therefore, this study aimed to examine the relationship between SMRs for malignant neoplasm of the pancreas and climatic factors, such as the amount of global solar radiation and the daily maximum temperature in Japan. Results The study used multiple linear regression models. Number of deaths and demographic data from 1998 to 2002 were used for the calculation of SMR. We employed mesh climatic data for Japan published in 2006 by the Japan Meteorological Agency. Regression coefficients for the amount of global solar radiation and the daily maximum temperature in males were -4.35 (p = 0.00034 and -2.81 (p Conclusion This study suggested that low solar radiation and low temperature might relate to the increasing risk of malignant neoplasm of the pancreas. Use of group data has a limitation in the case of evaluating environmental factors affecting health, since the impact of climatic factors on the human body varies according to individual lifestyles and occupations. Use of geographical mesh climatic data, however, proved useful as an index of risk or beneficial factors in a small study area. Further research using individual data is necessary to elucidate the relationship between climatic factors and the development of malignant neoplasm of the pancreas.

  5. Non-climatic factors and long-term, continental-scale changes in seasonally frozen ground

    Science.gov (United States)

    Shiklomanov, Nikolay I.

    2012-03-01

    ). In their recent paper entitled 'An observational 71-year history of seasonally frozen ground changes in Eurasian high latitudes', Frauenfeld and Zhang (2011) provided detailed analysis of soil temperature data to assess 1930-2000 trends in seasonal freezing depth. The data were obtained from 387 Soviet non-permafrost meteorological stations. The authors performed systematic, quality-controlled, integrative analysis over the entire former Soviet Union domain. The long-term changes in depth of seasonal freezing were discussed in relation to such forcing variables as air temperature, degree days of freezing/thawing, snow depth and summer precipitation as well as modes of the North Atlantic Oscillation. The spatially average approach adopted for the study provides a generalized continental-scale trend. The study greatly improves, expands and extends previous 1956-90 analysis of the ground thermal regime over the Eurasian high latitudes (Frauenfeld et al 2004). Although the work of Frauenfeld and Zhang (2011) is the most comprehensive assessment of the continental-scale long-term trends in seasonal freezing available to date, more detailed analysis is needed to determine the effect of climate change on seasonally frozen ground. It should be noted that, in addition to the variables considered for analysis, other non-climatic factors affect the depth of freezing propagation. Unlike the surface, which is influenced by the climate directly, the ground even at shallow depth receives a climatic signal that is substantially modified by edaphic processes, contributing to highly localized thermal sensitivities of the ground to climatic forcing. Subsurface properties, soil moisture, and snow and vegetation covers influence the depth of freezing. Topography also plays an important role in establishing the ground thermal regime. It is an important determinant of the amount of heat received by the ground surface, affects the distribution of snow and vegetation, and influences the

  6. Climate control of terrestrial carbon exchange across biomes and continents

    NARCIS (Netherlands)

    Yi, C.; Jacobs, C.M.J.; Moors, E.J.; Elbers, J.A.

    2010-01-01

    Understanding the relationships between climate and carbon exchange by terrestrial ecosystems is critical to predict future levels of atmospheric carbon dioxide because of the potential accelerating effects of positive climate–carbon cycle feedbacks. However, directly observed relationships between

  7. Climate control of terrestrial carbon exchange across biomes and continents

    DEFF Research Database (Denmark)

    Yi, Chuixiang; Ricciuto, Daniel; Li, Runze;

    2010-01-01

    Understanding the relationships between climate and carbon exchange by terrestrial ecosystems is critical to predict future levels of atmospheric carbon dioxide because of the potential accelerating effects of positive climate–carbon cycle feedbacks. However, directly observed relationships betwe...

  8. Analysis of Climatic Factors Influencing Walnut Distribution in the Main Producing Areas of Yunnan Province

    Institute of Scientific and Technical Information of China (English)

    Liangjun; XIAO; Ting; MA; Delu; Ning

    2013-01-01

    Using the data of 11 climatic factors on 40 counties in the main producing areas of walnut of Yunnan Province,we analyze the impact of various climatic factors on the distribution of Yunnan walnut.The results show that Yunnan walnut has a great expectation on temperature and moisture.Temperature,including average temperature in January,average temperature in July,the average annual temperature and accumulated temperature≥10℃,has the greatest impact on the distribution of Yunnan walnut,and is the primary dominant factor;moisture,including annual rainfall and average relative humidity,has a great impact on the distribution of Yunnan walnut,and is the secondary dominant factor.

  9. Perception of Transfer Climate Factors in the Macro and Micro Organizational Work Environment

    Science.gov (United States)

    Diggs, Byron Kenneth

    2011-01-01

    This qualitative study was designed to provide insight on the perceived transfer climate factors in the macro and micro organizational work environment that may influence an employee's willingness to transfer what was learned in a training program to the job. More specifically, the purpose of the study was to delineate descriptive patterns and…

  10. Factors influencing farmers’ choices of adaptation to climate change in Ekiti State, Nigeria

    Directory of Open Access Journals (Sweden)

    Oluwakemi Adeola Obayelu

    2014-06-01

    Full Text Available Climate change poses a great threat to human security through erratic rainfall patterns and decreasing crop yields, contributing to increased hunger. The perceptions of the indigenous people about climate change and their responses to climate change have significant roles to play in addressing climate change. Therefore a critical study on farmers’ choices of adaptation to is critical for ensuring food security poverty alleviation. A multi-stage random sampling technique was used to select 156 households in Ekiti state while descriptive statistics and multinomial logit were used to analyze the data obtained from the households. The results showed that the most widely used adaptation method by the farmers were soil and water conservation measures (67 percent. The multinomial logit analysis revealed that the factors explaining farmer’s choices of climate change adaptation include age of the farmers, gender of the household head, years of education, years of farming experience, household size, farmers information on climate change, farmers access to credit, farm income, non-farm income, livestock ownership and extension contact.

  11. Nonsquare Spectral Factorization for Nonlinear Control Systems

    NARCIS (Netherlands)

    Petersen, Mark A.; Schaft, Arjan J. van der

    2005-01-01

    This paper considers nonsquare spectral factorization of nonlinear input affine state space systems in continuous time. More specifically, we obtain a parametrization of nonsquare spectral factors in terms of invariant Lagrangian submanifolds and associated solutions of Hamilton–Jacobi inequalities.

  12. Moderating Effect of Negative Peer Group Climate on the Relation Between Men's Locus of Control and Aggression Toward Intimate Partners.

    Science.gov (United States)

    Schmidt, Megan R; Lisco, Claire G; Parrott, Dominic J; Tharp, Andra T

    2016-03-01

    The present study sought to examine the interactive effects of an external locus of control and interaction in a negative peer group climate on men's perpetration of physical aggression and infliction of injury toward their female intimate partners. Participants were 206 heterosexual males recruited from the metro-Atlanta community who completed self-report measures of external locus of control, involvement in a negative peer group climate, and physical aggression and infliction of injury against intimate partners during the past 12 months. Negative peer group climate was conceptualized as a peer group that displays behavior which may instigate aggressive norms, attitudes, and behaviors. Results indicated that men with an external locus of control were more likely to perpetrate physical aggression toward and inflict injury on their intimate partners if they reported high, but not low, involvement in a negative peer group climate. These results extend current research suggesting external locus of control as a risk factor for intimate partner aggression by highlighting the impact of negative peer groups. Implications and future intervention research are discussed.

  13. Climate change - An uncertainty factor in risk analysis of contaminated land.

    Science.gov (United States)

    Augustsson, Anna; Filipsson, Monika; Oberg, Tomas; Bergbäck, Bo

    2011-10-15

    Metals frequently occur at contaminated sites, where their potential toxicity and persistence require risk assessments that consider possible long-term changes. Changes in climate are likely to affect the speciation, mobility, and risks associated with metals. This paper provides an example of how the climate effect can be inserted in a commonly used exposure model, and how the exposure then changes compared to present conditions. The comparison was made for cadmium (Cd) exposure to 4-year-old children at a highly contaminated iron and steel works site in southeastern Sweden. Both deterministic and probabilistic approaches (through probability bounds analysis, PBA) were used in the exposure assessment. Potential climate-sensitive variables were determined by a literature review. Although only six of the total 39 model variables were assumed to be sensitive to a change in climate (groundwater infiltration, hydraulic conductivity, soil moisture, soil:water distribution, and two bioconcentration factors), the total exposure was clearly affected. For example, by altering the climate-sensitive variables in the order of 15% to 20%, the deterministic estimate of exposure increased by 27%. Similarly, the PBA estimate of the reasonable maximum exposure (RME, defined as the upper bound of the 95th percentile) increased by almost 20%. This means that sites where the exposure in present conditions is determined to be slightly below guideline values may in the future exceed these guidelines, and risk management decisions could thus be affected. The PBA, however, showed that there is also a possibility of lower exposure levels, which means that the changes assumed for the climate-sensitive variables increase the total uncertainty in the probabilistic calculations. This highlights the importance of considering climate as a factor in the characterization of input data to exposure assessments at contaminated sites. The variable with the strongest influence on the result was the

  14. Climate change - An uncertainty factor in risk analysis of contaminated land.

    Science.gov (United States)

    Augustsson, Anna; Filipsson, Monika; Oberg, Tomas; Bergbäck, Bo

    2011-10-15

    Metals frequently occur at contaminated sites, where their potential toxicity and persistence require risk assessments that consider possible long-term changes. Changes in climate are likely to affect the speciation, mobility, and risks associated with metals. This paper provides an example of how the climate effect can be inserted in a commonly used exposure model, and how the exposure then changes compared to present conditions. The comparison was made for cadmium (Cd) exposure to 4-year-old children at a highly contaminated iron and steel works site in southeastern Sweden. Both deterministic and probabilistic approaches (through probability bounds analysis, PBA) were used in the exposure assessment. Potential climate-sensitive variables were determined by a literature review. Although only six of the total 39 model variables were assumed to be sensitive to a change in climate (groundwater infiltration, hydraulic conductivity, soil moisture, soil:water distribution, and two bioconcentration factors), the total exposure was clearly affected. For example, by altering the climate-sensitive variables in the order of 15% to 20%, the deterministic estimate of exposure increased by 27%. Similarly, the PBA estimate of the reasonable maximum exposure (RME, defined as the upper bound of the 95th percentile) increased by almost 20%. This means that sites where the exposure in present conditions is determined to be slightly below guideline values may in the future exceed these guidelines, and risk management decisions could thus be affected. The PBA, however, showed that there is also a possibility of lower exposure levels, which means that the changes assumed for the climate-sensitive variables increase the total uncertainty in the probabilistic calculations. This highlights the importance of considering climate as a factor in the characterization of input data to exposure assessments at contaminated sites. The variable with the strongest influence on the result was the

  15. Colon cancer controls versus population controls in case-control studies of occupational risk factors

    Directory of Open Access Journals (Sweden)

    Sabroe Svend

    2004-04-01

    Full Text Available Abstract Background Since updated population registers do not exist in many countries it is often difficult to sample valid population controls from the study base to a case-control study. Use of patient controls is an alternative option if the exposure experience under study for these patients are interchangeable with the experience for population controls. Patient controls may even be preferable from population controls under certain conditions. In this study we examine if colon cancer patients can serve as surrogates for proper population controls in case-control studies of occupational risk factors. Methods The study was conducted from 1995 to 1997. Incident colon cancer controls (N = 428 aged 35–69 years with a histological verified diagnosis and population controls (N = 583 were selected. Altogether 254 (59% of the colon cancer controls and 320 (55% of the population controls were interviewed about occupational, medical and life style conditions. Results No statistical significant difference for educational level, medical history or smoking status was seen between the two control groups. There was evidence of a higher alcohol intake, less frequent work as a farmer and less exposure to pesticides among colon cancer controls. Conclusions Use of colon cancer controls may provide valid exposure estimates in studies of many occupational risk factors for cancer, but not for studies on exposure related to farming.

  16. Socio-economic and Climate Factors Associated with Dengue Fever Spatial Heterogeneity: A Worked Example in New Caledonia.

    Directory of Open Access Journals (Sweden)

    Magali Teurlai

    2015-12-01

    Full Text Available Understanding the factors underlying the spatio-temporal distribution of infectious diseases provides useful information regarding their prevention and control. Dengue fever spatio-temporal patterns result from complex interactions between the virus, the host, and the vector. These interactions can be influenced by environmental conditions. Our objectives were to analyse dengue fever spatial distribution over New Caledonia during epidemic years, to identify some of the main underlying factors, and to predict the spatial evolution of dengue fever under changing climatic conditions, at the 2100 horizon.We used principal component analysis and support vector machines to analyse and model the influence of climate and socio-economic variables on the mean spatial distribution of 24,272 dengue cases reported from 1995 to 2012 in thirty-three communes of New Caledonia. We then modelled and estimated the future evolution of dengue incidence rates using a regional downscaling of future climate projections.The spatial distribution of dengue fever cases is highly heterogeneous. The variables most associated with this observed heterogeneity are the mean temperature, the mean number of people per premise, and the mean percentage of unemployed people, a variable highly correlated with people's way of life. Rainfall does not seem to play an important role in the spatial distribution of dengue cases during epidemics. By the end of the 21st century, if temperature increases by approximately 3 °C, mean incidence rates during epidemics could double.In New Caledonia, a subtropical insular environment, both temperature and socio-economic conditions are influencing the spatial spread of dengue fever. Extension of this study to other countries worldwide should improve the knowledge about climate influence on dengue burden and about the complex interplay between different factors. This study presents a methodology that can be used as a step by step guide to model

  17. Climatization

    DEFF Research Database (Denmark)

    Grant, Stephen; Tamason, Charlotte Crim; Jensen, Peter Kjær Mackie

    2015-01-01

    by climate change, in order to reach an intended goal or to distractthe discussion from the real problem which might have a different root course than caused bythe climate change effects. The implications of climatization are currently unclear – particularly to what extent climatizinga disaster might......In recent years, there has been a developing trend of labelling some disasters as ‘climatechange disasters’. In doing so, a discursive phenomenon can emerge that the authors havecoined ‘climatization’ which is specified as framing a disastrous event or degraded environmentalcondition as caused...... in the context of Bangladesh – a country that is expectedto be among the worst affected by climate change and a country in which some peopleclaim the effects of climate change can already be seen. A qualitative field study whichincluded key informant interviews, focus group discussions and a literature review...

  18. The effect of family climate on risky driving of young novices: the moderating role of attitude and locus of control.

    Science.gov (United States)

    Carpentier, Aline; Brijs, Kris; Declercq, Katrien; Brijs, Tom; Daniels, Stijn; Wets, Geert

    2014-12-01

    The aim of the study was to examine the relative importance of young novice drivers' family climate on their driving behavior. A sample of young novice drivers (N=171) between the age of 17 and 24, who held their permanent (or temporary) driver's license for no longer than one year, participated. The questionnaire included items related to the participants' family climate, 3 socio-cognitive determinants (i.e., attitude, locus of control and social norm), and risky driving behaviors. We expected both family climate and the socio-cognitive determinants to exert a direct effect on risky driving. Furthermore we hypothesized that the socio-cognitive determinants would moderate the impact of family climate on risky driving. The results showed that the effect of family climate on risky driving only originated from one single factor (i.e., noncommitment). Besides that, the results confirmed the importance of the three socio-cognitive determinants to the degree that attitude, locus of control, and social norm significantly predicted the self-reported risky driving. In line of what we hypothesized, attitude moderated the relationship between noncommitment and risky driving. Lastly, we found an unexpected three-way interaction which indicated that locus of control moderated the relation between noncommitment and risky driving only when young drivers' attitude was risk-supportive. We recommend scholars and practitioners to take into account the interaction between external sources of influence (such as an individual's family climate) and more personally oriented dispositions (such as an individual's attitude, social norm and locus of control) when trying to explain and change young novices' risky driving.

  19. The Influence of Effortful Control and Empathy on Perception of School Climate

    Science.gov (United States)

    Zorza, Juan P.; Marino, Julián; Mesas, Alberto Acosta

    2015-01-01

    The purpose of this study was to determine the predictive power of effortful control (EC) and empathy for perception of school climate. Self-report measures of EC, dispositional empathy, and perception of school climate were obtained for 398 students (204 females) aged 12 to 13. Sociometric status was peer-evaluated, and academic achievement was…

  20. Climate control based on stomatal behavior in a semi-closed greenhouse system 'Aircokas'

    NARCIS (Netherlands)

    Voogt, J.; Weel, van P.A.

    2008-01-01

    Climate control in a greenhouse is usually based on maintaining a specific air temperature, sometimes adjusted to the available light level or the cost of energy. According to theoretical physiological knowledge optimal photosynthesis depends on the behavior of the stomata. No existing climate contr

  1. Patterns of tree species diversity in relation to climatic factors on the Sierra Madre Occidental, Mexico.

    Directory of Open Access Journals (Sweden)

    Ramón Silva-Flores

    Full Text Available Biological diversity can be defined as variability among living organisms from all sources, including terrestrial organisms, marine and other aquatic ecosystems, and the ecological complexes which they are part of. This includes diversity within species, between species, and of ecosystems. Numerous diversity indices combine richness and evenness in a single expression, and several climate-based explanations have been proposed to explain broad-scale diversity patterns. However, climate-based water-energy dynamics appears to be an essential factor that determines patterns of diversity. The Mexican Sierra Madre Occidental occupies an area of about 29 million hectares and is located between the Neotropical and Holarctic ecozones. It shelters a high diversity of flora, including 24 different species of Pinus (ca. 22% on the whole, 54 species of Quercus (ca. 9-14%, 7 species of Arbutus (ca. 50% and many other trees species. The objectives of this study were to model how tree species diversity is related to climatic and geographic factors and stand density and to test the Metabolic Theory, Productivity-Diversity Hypothesis, Physiological Tolerance Hypothesis, Mid-Domain Effect, and the Water-Energy Dynamic Theory on the Sierra Madre Occidental, Durango. The results supported the Productivity-Diversity Hypothesis, Physiological Tolerance Hypothesis and Water-Energy Dynamic Theory, but not the Mid-Domain Effect or Metabolic Theory. The annual aridity index was the variable most closely related to the diversity indices analyzed. Contemporary climate was found to have moderate to strong effects on the minimum, median and maximum tree species diversity. Because water-energy dynamics provided a satisfactory explanation for the patterns of minimum, median and maximum diversity, an understanding of this factor is critical to future biodiversity research. Quantile regression of the data showed that the three diversity parameters of tree species are generally

  2. Climatic controls and climate proxy potential of Lewis Glacier, Mt Kenya

    Science.gov (United States)

    Prinz, Rainer; Nicholson, Lindsey; Gurgiser, Wolfgang; Mölg, Thomas; Kaser, Georg

    2016-04-01

    Glaciers in the tropics can provide information about regional climate, its dynamics, and its evolution over decadal and centennial time scales, if their interaction with the atmosphere is understood, and their changes are documented or reconstructed. The glaciers on Mount Kenya capture a climate signal from the mid troposphere at about 5 km a.s.l., where our knowledge of climate change is scarce and controversial. We use in-situ meteorological and glaciological observations to optimize and validate a physically-based, process-orientated energy and mass balance model to quantify the exchange processes between the glacier surface and the atmosphere above and to explore the sensitivity of energy and mass exchanges to changing climatic conditions. Currently the glacier loses mass due to the imbalance between insufficient accumulation and enhanced melt, because radiative energy gains cannot be compensated by turbulent energy sinks. Exchanging model input data with synthetic climate scenarios, which were sampled from the meteorological measurements and account for coupled climatic variable perturbations, reveal that the current mass balance is most sensitive to changes in atmospheric moisture (via its impact on solid precipitation, cloudiness and surface albedo). Scenarios with lower air temperatures are drier and associated with lower accumulation and increased net radiation due to reduced cloudiness and albedo. Hence, similar to the glaciers of nearby Kilimanjaro, the recession of Lewis Glacier is not because of increased air temperatures, but because of decreased atmospheric moisture. If the climate scenarios currently producing positive mass balances are applied to Lewis Glacier's late 19th century maximum extent (L19), negative mass balances are the result, meaning that the conditions required sustaining the glacier in its L19 extent are not reflected in today's climate observations. Alternatively, a balanced mass budget for the L19 extent can be explained by

  3. Factors controlling the initiation of Snowball Earth events

    Science.gov (United States)

    Voigt, A.

    2012-12-01

    During the Neoproterozoic glaciations tropical continents were covered by active glaciers that extended down to sea level. To explain these glaciers, the Snowball Earth hypothesis assumes that oceans were completely sea-ice covered during these glaciation, but there is an ongoing debate whether or not some regions of the tropical oceans remained open. In this talk, I will describe past and ongoing climate modelling activities with the comprehensive coupled climate model ECHAM5/MPI-OM that identify and compare factors that control the initiation of Snowball Earth events. I first show that shifting the continents from their present-day location to their Marinoan (635 My BP) low-latitude location increases the planetary albedo, cools the climate, and thereby allows Snowball Earth initiation at higher levels of total solar irradiance and atmospheric CO2. I then present simulations with successively lowered bare sea-ice albedo, disabled sea-ice dynamics, and switched-off ocean heat transport. These simulations show that both lowering the bare sea-ice albedo and disabling sea-ice dynamics increase the critical sea-ice cover in ECHAM5/MPI-OM, but sea-ice dynamics due to strong equatorward sea-ice transport have a much larger influence on the critical CO2. Disabling sea-ice transport allows a state with sea-ice margin at 10 deg latitude by virtue of the Jormungand mechanism. The accumulation of snow on land, in combination with tropical land temperatures below or close to freezing, suggests that tropical land glaciers could easily form in such a state. However, in contrast to aquaplanet simulations without ocean heat transport, there is no sign of a Jormungand hysteresis in the coupled simulations. Ocean heat transport is not responsible for the lack of a Jormungand hysteresis in the coupled simulations. By relating the above findings to previous studies, I will outline promising future avenues of research on the initiation of Snowball Earth events. In particular, an

  4. Effect of climate factors on wood veneers exposed to outdoor conditions in black sea region

    OpenAIRE

    Köse, Gaye; Temiz, Ali; Akbaş, Selçuk; Özkan, Emre

    2013-01-01

    In this study, 2×100×200 mm wood veneers obtained from Scots pine (Pinus sylvestris L.), European black pine (Pinus nigra Arn.) and beech (Fagus orientalis L.) wood were exposed to outdoor climate conditions at three different cities (Trabzon, Artvin, and Kastamonu) of Black Sea region in Turkey for totally 4 months from May to August, 2012. The aim of this study was to investigate the effect of climate factors on the changes occurred on different types of wood veneers that were subjected to ...

  5. Zonal Differences in Correlation Patterns Between Soil Organic Carbon and Climate Factors at Multi-extent

    Institute of Scientific and Technical Information of China (English)

    QIN Falyu; SHI Xuezheng; XU Shengxiang; YU Dongsheng; WANG Dandan

    2016-01-01

    Studying the relationship between climate factors and soil organic carbon (SOC) is vitally important.However,how SOC responses to climate (temperature and precipitation) at cohesive extents is poorly studied.Two transects of approximately the same length (transect P and transect T) were selected to examine the variation of SOC content in relation to mean annual temperature (MAT) and mean annual precipitation (MAP).The coefficients of partial correlation between SOC density and MAT (Rt) and MAP (Rp) were determined to quantify the relationships between SOC density and the two climate factors.The results indicated that for transect T,Rt was statistically significant once the extent level was greater than or equal to two fundamental extent units,while for transect P,Rp showed statistical significance only at extent levels which were greater than two fundamental extent units.At the same extent levels but in different transects,Rts exhibited no zonal difference,but Rps did once the extent level was greater than two fundamental extent units.Therefore,to study the relationship between SOC density and different climate factors,different minimum extent levels should be examined.The results of this paper could deepen the understanding of the impacts that SOC pool has on terrestrial ecosystem and global carbon cycling.

  6. Snow Cover Variations and Controlling Factors at Upper Heihe River Basin, Northwestern China

    Directory of Open Access Journals (Sweden)

    Yunbo Bi

    2015-05-01

    Full Text Available Snow is an important water resource and greatly influences water availability in the downstream areas. In this study, snow cover variations of the Upper Heihe River Basin (UHRB during hydrological years (HY 2003–2013 (September through August is examined using the flexible multiday-combined MODIS snow cover products. Spatial distribution and pattern of snow cover from year to year for the basin is found to be relatively stable, with maximum snow cover area (SCA and snow cover days occurring in HY2004, HY2008 and HY2012. A method, based on correlation coefficients between SCA and climate factors (mainly air temperature and precipitation, is presented to identify the threshold altitude that determines contributions of climate factors to SCA. A threshold altitude of 3650 ± 150 m is found for the UHRB, where below this altitude, both air temperature (Tair and precipitation are negative factors on SCA, except in the winter season when both are positive factors. Above the threshold altitude, precipitation acts as a positive factor except in summer, while Tair is a negative factor except in autumn. Overall, Tair is the primary controlling factor on SCA below the threshold altitude, while precipitation is the primary controlling factor on SCA above the threshold altitude.

  7. Two thresholds determine climatic control of forest-fire size in Europe

    Directory of Open Access Journals (Sweden)

    L. Loepfe

    2012-07-01

    Full Text Available Fire weather indices predict fire extent from meteorological conditions assuming a monotonic function; this approach is frequently used to predict future fire patterns under climate change scenarios using linear extrapolation. However, the relationship between weather and fire extent may potentially depend on the existence of fuel humidity thresholds above which this relationship changes dramatically, challenging this statistical approach. Here we combine the continuous and the threshold approaches to analyze satellite-detected fires in Europe during 2001–2010 in relation to meteorological conditions, showing that fire size response to increasing dryness follows a ramp function, i.e. with two plateaus separated by a phase of monotonic increase. This study confirms that at a continental and a high-resolution temporal scales, large fires are very unlikely to occur under moist conditions, but it also reveals that fire size stops to be controlled by fuel humidity above a given threshold of dryness. Thus, fuel humidity control only applies when fire is not limited by other factors such as fuel load, as large fires are virtually absent in dry regions with less than 500 mm of average annual rainfall, i.e. where fuel amount is insufficient. In regions with sufficient fuel, other factors such as fire suppression or fuel discontinuity can impede large fires even under very dry weather conditions. These findings are relevant under current climatic trends in which the fire season length, in terms of number of days with DC (drought code values above the observed thresholds (break points, is increasing in many parts of the Mediterranean, while it is decreasing in Eastern Europe and remains unchanged in Central Europe.

  8. Coupled Effects of Climatic and Socio-economic Factors on Winter Cropping in India

    Science.gov (United States)

    Jain, M.; Mondal, P.; Galford, G. L.; DeFries, R. S.

    2015-12-01

    India is predicted to be one of the most vulnerable regions in terms of agricultural sensitivity to future climate changes. Approximately 69% of India's population is rural, and over 55% of the working population relies on agriculture for sustenance and livelihoods. Indian smallholder farmers who own less than 2 ha of farmland represent 78% of the total Indian farmers and produce 41% of the country's food crops. These smallholder farmers are among some of the most vulnerable communities to climatic and economic changes due to limited access to technology, infrastructure, markets, and institutional or financial support in the case of adverse climatic events. Baseline information on agricultural sensitivity to climate variability will provide useful information for regional-level, and eventually state- and national-level, strategies and policies that promote adaption to climate variability. We use a decade of remote sensing analysis of cropping patterns and climatic factors along with census data for irrigation and demographic factors to understand winter cropping trajectories across agro-ecological zones in India. Findings from multiple agro-ecological zones indicate that there are three primary trajectories in winter cropping in India - increasing, fluctuating, and decreasing. In the Central Indian Highlands, for example, the most dominant trend is that of fluctuating cropped area, ranging between ~37,300 km2 in 2010 and ~21,100 km2 in 2013, which is associated with village-level access to irrigation and local labor dynamics. Clay soil type and increasing irrigation coverage were associated with intensification. Yet, suitable soil type and access to irrigation do not reduce vulnerability to high daytime temperatures that is negatively associated with winter crop cover. With pronounced winter warming projected in the coming decades, effective adaptation by smallholder farmers would require additional strategies, such as access to fine-scale temperature forecasts

  9. Climate and terrain factors explaining streamflow response and recession in Australian catchments

    Directory of Open Access Journals (Sweden)

    A. I. J. M. van Dijk

    2010-01-01

    Full Text Available Daily streamflow data were analysed to assess which climate and terrain factors best explain streamflow response in 183 Australian catchments. Assessed descriptors of catchment response included the parameters of fitted baseflow models, and baseflow index (BFI, average quick flow and average baseflow derived by baseflow separation. The variation in response between catchments was compared with indicators of catchment climate, morphology, geology, soils and land use. Spatial coherence in the residual unexplained variation was investigated using semi-variogram techniques. A linear reservoir model (one parameter; recession coefficient produced baseflow estimates as good as those obtained using a non-linear reservoir (two parameters and for practical purposes was therefore considered an appropriate balance between simplicity and explanatory performance. About a third (27–34% of the spatial variation in recession coefficients and BFI was explained by catchment climate indicators, with another 53% of variation being spatially correlated over distances of 100–150 km, probably indicative of substrate characteristics not captured by the available soil and geology data. The shortest recession half-times occurred in the driest catchments and were attributed to intermittent occurrence of fast-draining (possibly perched groundwater. Most (70–84% of the variation in average baseflow and quick flow was explained by rainfall and climate characteristics; another 20% of variation was spatially correlated over distances of 300–700 km, possibly reflecting a combination of terrain and climate factors. It is concluded that catchment streamflow response can be predicted quite well on the basis of catchment climate alone. The prediction of baseflow recession response should be improved further if relevant substrate properties were identified and measured.

  10. Management and Climate Controls on Fire Trends in the Continental United States

    Science.gov (United States)

    Lin, H.; McCarty, J. L.; Wang, D.; Rogers, B. M.; Morton, D. C.; Collatz, G. J.; Randerson, J. T.

    2012-12-01

    Fires in croplands, plantations, and rangelands contribute significantly to fire emissions in the United States, yet are often overshadowed by forest fires in both scale and in the resources invested for management. Here we quantified decadal trends, interannual variability, and seasonality of satellite observations of active fires as a function of management type in the continental U.S. during 2001-2010. We used the Monitoring Trends in Burn Severity Database (MTBS) to identify the location of large wildland fires and the MODIS Land Cover Type Product (MCD12Q1) to identify agricultural burning in croplands. A third class of fires, defined as prescribed or other fires included all residual fires not attributed to wildland or cropland fire types. Wildland fires dominated the interannual variation for U.S. active fires; however, there were no significant trends by region over the last decade. Agricultural and other/prescribed fires were responsible for 70% of total active fires, 50% of which were in the south and southeastern United States where contributions from wildland fires was relatively small. In the west, agricultural fires had a decreasing trend at a rate of 6% per year, mainly during the harvest season of October. Except for the west, prescribed fires were in-phase with agricultural fires on both seasonal and interannual timescales, possibly reflecting the similar management strategies. We also performed correlation analysis between fires and potential evapotranspiration (PE) to examine how climate controls varied by fire type. While climate is the dominant factor for wildland fires, agricultural and other non-wildland fires show no direct relationship to PE. Our result suggests that by targeting agricultural and prescribed fire management, there is potential to significantly reduce landscape fire emissions within the U.S., despite expected changes in climate over the next several decades. The trends (p < 0.01) in annual active fire detections across the

  11. Climatic and Landscape Controls on Storage Capacity of Urban Stormwater Control Measures (SCMs): Implications for Stormwater-Stream Connectivity

    Science.gov (United States)

    Fanelli, R. M.; Prestegaard, K. L.; Palmer, M.

    2015-12-01

    Urbanization alters watershed hydrological processes; impervious surfaces increase runoff generation, while storm sewer networks increase connectivity between runoff sources and streams. Stormwater control measures (SCMs) that enhance stormwater infiltration have been proposed to mitigate these effects by functioning as stormwater sinks. Regenerative stormwater conveyances structures (RSCs) are an example of infiltration-based SCMs that are placed between storm sewer outfalls and perennial stream networks. Given their location, RSCs act as critical nodes that regulate stormwater-stream connectivity. Therefore, the storage capacity of a RSC structure may exert a major control on the frequency, duration, and magnitude of these connections. This project examined both hydrogeological and hydro-climatic factors that could influence storage capacity of RSC structures. We selected three headwater (5-48 ha) urban watersheds near Annapolis, Maryland, USA. Each watershed is drained by first-order perennial streams and has been implemented with a RSC structure. We conducted high-frequency precipitation and stream stage monitoring below the outlet of each RSC structure for a 1-year period. We also instrumented one of the RSC structures with groundwater wells to monitor changes in subsurface storage over time. Using these data, we 1) identified rainfall thresholds for RSC storage capacity exceedance; 2) quantified the frequency and duration of connectivity when the storage capacity of each RSC was exceeded; and 3) evaluated both event-scale and seasonal changes in groundwater levels within the RSC structure. Precipitation characteristics and antecedent precipitation indices influenced the frequency and duration of stormwater-stream connections. We hypothesize both infiltration limitations and storage limitations of the RSCs contributed to the temporal patterns we observed in stormwater-stream connectivity. We also observed reduced storage potential as contributing area and

  12. Spatiotemporal Characteristics of Reference Evapotranspiration and Its Sensitivity Coefifcients to Climate Factors in Huang-Huai-Hai Plain, China

    Institute of Scientific and Technical Information of China (English)

    YANG Jian-ying; LIU Qin; MEI Xu-rong; YAN Chang-rong; JU Hui; XUJian-wen

    2013-01-01

    Climate change will have important implications in water shore regions, such as Huang-Huai-Hai (3H) plain, where expected warmer and drier conditions might augment crop water demand. Sensitivity analysis is important in understanding the relative importance of climatic variables to the variation in reference evapotranspiration (ET0). In this study, the 51-yrET0 during winter wheat and summer maize growing season were calculated from a data set of daily climate variables in 40 meteorological stations. Sensitivity maps for key climate variables were estimated according to Kriging method and the spatial pattern of sensitivity coefifcients for these key variables was plotted. In addition, the slopes of the linear regression lines for sensitivity coefifcients were obtained. Results showed thatET0 during winter wheat growing season accounted for the largest proportion of annualET0, due to its long phenological days, whileET0 was detected to decrease signiifcantly with the magnitude of 0.5 mmyr-1 in summer maize growing season. Solar radiation is considered to be the most sensitive and primarily controlling variable for negative trend inET0 for summer maize season, and higher sensitive coefifcient value ofET0 to solar radiation and temperature were detected in east part and southwest part of 3H plain respectively. Relative humidity was demonstrated as the most sensitive factor forET0 in winter wheat growing season and declining relativity humidity also primarily controlled a negative trend inET0, furthermore the sensitivity coefifcient to relative humidity increased from west to southeast. The eight sensitivity centrals were all found located in Shandong Province. TheseET0 along with its sensitivity maps under winter wheat-summer maize rotation system can be applied to predict the agricultural water demand and will assist water resources planning and management for this region.

  13. Climatic controls and climate proxy potential of Lewis Glacier, Mt Kenya

    Directory of Open Access Journals (Sweden)

    R. Prinz

    2015-07-01

    Full Text Available The Lewis Glacier on Mt Kenya is one of the best studied tropical glaciers and has experienced considerable retreat since a maximum extent in the late 19th century (L19. From distributed mass and energy balance modelling, this study evaluates the current sensitivity of the surface mass and energy balance to climatic drivers, explores climate conditions under which the L19 maximum extent might have sustained, and discusses the potential for using the glacier retreat to quantify climate change. Multiyear meteorological measurements at 4828 m provide data for input, optimization and evaluation of a spatially distributed glacier mass balance model to quantify the exchanges of energy and mass at the glacier–atmosphere interface. Currently the glacier loses mass due to the imbalance between insufficient accumulation and enhanced melt, because radiative energy gains cannot be compensated by turbulent energy sinks. Exchanging model input data with synthetic climate scenarios, which were sampled from the meteorological measurements and account for coupled climatic variable perturbations, reveal that the current mass balance is most sensitive to changes in atmospheric moisture (via its impact on solid precipitation, cloudiness and surface albedo. Positive mass balances result from scenarios with an increase of annual (seasonal accumulation of 30 % (100 %, compared to values observed today, without significant changes in air temperature required. Scenarios with lower air temperatures are drier and associated with lower accumulation and increased net radiation due to reduced cloudiness and albedo. If the scenarios currently producing positive mass balances are applied to the L19 extent, negative mass balances are the result, meaning that the conditions required to sustain the glacier in its L19 extent are not reflected in today's observations. Alternatively, a balanced mass budget for the L19 extent can be explained by changing model parameters that imply

  14. ANALYSIS OF THE MAIN CLIMATIC FACTORS AND THEIR IMPACT ON CROP PRODUCTION

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    Elena COFAS

    2014-06-01

    Full Text Available The data records of crop productivity shows wide fluctuations from one year to another, these being influencedsignificantly by the conditions climate variability. In general, climate variability affects all sectors of the economy,but, in particular, the agricultural sector it is the most exposed. This study aims an statistical analyze the effectsinduced by climatological factors on the main agricultural crops, quantified in agroclimatic risks at local andregional levels, for the period 1990-2000, in Ialomita county. Thus, we used statistical data relating to the twogroups of variables: 1 agricultural productions (for the main crops – wheat and rye, corn, sunflower, sugar beet,potatoes, vegetables and 2 climatology data (for the main climatological factors – average temperatures, rainfall,the sunshine duration and the nebulosity and we analysed the possible correlations for those major variables.

  15. Revisiting factors controlling methane emissions from high-Arctic tundra

    Directory of Open Access Journals (Sweden)

    M. Mastepanov

    2013-07-01

    Full Text Available The northern latitudes are experiencing disproportionate warming relative to the mid-latitudes, and there is growing concern about feedbacks between this warming and methane production and release from high-latitude soils. Studies of methane emissions carried out in the Arctic, particularly those with measurements made outside the growing season, are underrepresented in the literature. Here we present results of 5 yr (2006–2010 of automatic chamber measurements at a high-Arctic location in Zackenberg, NE Greenland, covering both the growing seasons and two months of the following freeze-in periods. The measurements show clear seasonal dynamics in methane emission. The start of the growing season and the increase in CH4 fluxes were strongly related to the date of snowmelt. Within each particular growing season, CH4 fluxes were highly correlated with the soil temperature (R2 > 0.75, which is probably explained by high seasonality of both variables, and weakly correlated with the water table. The greatest variability in fluxes between the study years was observed during the first part of the growing season. Somewhat surprisingly, this variability could not be explained by commonly known factors controlling methane emission, i.e. temperature and water table position. Late in the growing season CH4 emissions were found to be very similar between the study years (except the extremely dry 2010 despite large differences in climatic factors (temperature and water table. Late-season bursts of CH4 coinciding with soil freezing in the autumn were observed during at least three years. The cumulative emission during the freeze-in CH4 bursts was comparable in size with the growing season emission for the year 2007, and about one third of the growing season emissions for the years 2009 and 2010. In all three cases the CH4 burst was accompanied by a corresponding episodic increase in CO2 emission, which can compose a significant contribution to the annual CO2

  16. Assessing the significance of climate and community factors on urban water demand

    Directory of Open Access Journals (Sweden)

    Md Mahmudul Haque

    2015-12-01

    Full Text Available Ensuring adequate water supply to urban areas is a challenging task due to factors such as rapid urban growth, increasing water demand and climate change. In developing a sustainable water supply system, it is important to identify the dominant water demand factors for any given water supply scheme. This paper applies principal components analysis to identify the factors that dominate residential water demand using the Blue Mountains Water Supply System in Australia as a case study. The results show that the influence of community intervention factors (e.g. use of water efficient appliances and rainwater tanks on water demand are among the most significant. The result also confirmed that the community intervention programmes and water pricing policy together can play a noticeable role in reducing the overall water demand. On the other hand, the influence of rainfall on water demand is found to be very limited, while temperature shows some degree of correlation with water demand. The results of this study would help water authorities to plan for effective water demand management strategies and to develop a water demand forecasting model with appropriate climatic factors to achieve sustainable water resources management. The methodology developed in this paper can be adapted to other water supply systems to identify the influential factors in water demand modelling and to devise an effective demand management strategy.

  17. The impact of climate factors on the prevalence of urolithiasis in Northern Taiwan

    OpenAIRE

    Kuo-Jen Lin; Po-Hung Lin; Sheng-Hsien Chu; Hsiao-Wen Chen; Ta-Min Wang; Yang-Jen Chiang; Kuan-Lin Liu; Hsu-Han Wang

    2014-01-01

    Background: Urolithiasis is a common disease with high prevalence and recurrence. Its incidence varies in different geographic locations, and there are evidences that meteorological factors also affect urinary stone formation. The aim of this study is to analyze the effects of climate parameters on the numbers of shockwave treatments for urinary stones in our hospital, in order to understand the effects of these parameters on the prevalence of urolithiasis in northern Taiwan. Methods: We r...

  18. Key factors for assessing climate benefits of natural gas versus coal electricity generation

    International Nuclear Information System (INIS)

    Assessing potential climate effects of natural gas versus coal electricity generation is complicated by the large number of factors reported in life cycle assessment studies, compounded by the large number of proposed climate metrics. Thus, there is a need to identify the key factors affecting the climate effects of natural gas versus coal electricity production, and to present these climate effects in as clear and transparent a way as possible. Here, we identify power plant efficiencies and methane leakage rates as the factors that explain most of the variance in greenhouse gas emissions by natural gas and coal power plants. Thus, we focus on the role of these factors in determining the relative merits of natural gas versus coal power plants. We develop a simple model estimating CO2 and CH4 emissions from natural gas and coal power plants, and resulting temperature change. Simple underlying physical changes can be obscured by abstract evaluation metrics, thus we focus our analysis on the time evolution of global mean temperature. We find that, during the period of plant operation, if there is substantial methane leakage, natural gas plants can produce greater near-term warming than coal plants with the same power output. However, if methane leakage rates are low and power plant efficiency is high, natural gas plants can produce some reduction in near-term warming. In the long term, natural gas power plants produce less warming than would occur with coal power plants. However, without carbon capture and storage natural gas power plants cannot achieve the deep reductions that would be required to avoid substantial contribution to additional global warming. (letter)

  19. THE ROLE OF CLIMATIC FACTORS ON FOREST LANDSCAPE CHANGE IN THE GURGHIU BASIN

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    M. L. NEAGU

    2012-03-01

    Full Text Available Wind is the main factor involved in changing the natural balance of forest ecosystems from Gurghiu hydrographic basin. Strong winds are responsible for windthrows, especially in spruce arboretums, the most representative of the wood species form the studied area. Trees can be partially (bending of trunks, branches and broken tops or totally (pulling the roots damaged. Windthrows occurrence is closely related to the climatic factors, physical-geographical conditions (slope, soil characteristics and arboretum characteristics (structure, age, consistency are also important. The imbalance induced by those phenomena is emphasized by pest invasions (especially Ips Typographus which are quite frequent after windthrows.Our study represents a detailed analysis of the way in which the structure and the balance of the forest ecosystems of Gurghiu basin undergo major changes, because the climatic factors (wind, snow action. Case study is the windthrow occurred on June 2010, when 200,000 m³ of wood was windthrowed, over a total area of ​​5,953 ha in P.U. II Isticeu (Fâncel Forest Range and partially in P.U. I Glăjărie (the same forest range. The methodology used includes the analysis of climatic data, statistical data processing, GIS techniques for mapping the areas vulnerable to windthrows, synthesis.

  20. Forecasting Malaria Cases Using Climatic Factors in Delhi, India: A Time Series Analysis

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    Varun Kumar

    2014-01-01

    Full Text Available Background. Malaria still remains a public health problem in developing countries and changing environmental and climatic factors pose the biggest challenge in fighting against the scourge of malaria. Therefore, the study was designed to forecast malaria cases using climatic factors as predictors in Delhi, India. Methods. The total number of monthly cases of malaria slide positives occurring from January 2006 to December 2013 was taken from the register maintained at the malaria clinic at Rural Health Training Centre (RHTC, Najafgarh, Delhi. Climatic data of monthly mean rainfall, relative humidity, and mean maximum temperature were taken from Regional Meteorological Centre, Delhi. Expert modeler of SPSS ver. 21 was used for analyzing the time series data. Results. Autoregressive integrated moving average, ARIMA (0,1,1 (0,1,012, was the best fit model and it could explain 72.5% variability in the time series data. Rainfall (P value = 0.004 and relative humidity (P value = 0.001 were found to be significant predictors for malaria transmission in the study area. Seasonal adjusted factor (SAF for malaria cases shows peak during the months of August and September. Conclusion. ARIMA models of time series analysis is a simple and reliable tool for producing reliable forecasts for malaria in Delhi, India.

  1. A Critical Analysis of Climate Change Factors and its Projected Future Values in Delta State, Nigeria

    Directory of Open Access Journals (Sweden)

    Emaziye, P. O., R. N. Okoh

    2012-06-01

    Full Text Available The study focused on the critical analysis of climate change factors (temperature and rainfall and its projected future values in the state. The main objective was to determine the trends of climate change factors (temperature and rainfall. And the specific objective was to determine the projected future trends of climate change factors in the state. Multistage sampling procedure was used in the random selection of states, local government, communities and rural households for the research study. Annual mean time series data of temperature and rainfall were collected from Nigerian Meteorological Agency (NIMET. Data were also obtained from structure questionnaire survey. The collected data were analyzed using descriptive statistics, trend analysis and growth model. The study reveals that there were increasing trends of temperature values and decreasing rainfall values in the state. But their projected future values witnessed an increasing trend. The increasing trends in temperature values may lead to a situation were crops will be smothered by excessive heat thereby reducing food production in the state. The study therefore recommends that meteorological station units should be established in the rural farming households in the state where accessibility is extremely difficult. This will make available meteorological data (information to the reach of the poor rural farming household for the attainment of food production.

  2. Transmission of Haemorrhagic Fever with Renal Syndrome in China and the Role of Climate Factors: A Review

    Directory of Open Access Journals (Sweden)

    Alana Hansen

    2015-04-01

    Full Text Available Haemorrhagic fever with renal syndrome (HFRS is a rodent-borne disease that poses a serious public health threat in China. HFRS is caused by hantaviruses, mainly Seoul virus in urban areas and Hantaan virus in agricultural areas. Although preventive measures including vaccination programs and rodent control measures have resulted in a decline in cases in recent years, there has been an increase in incidence in some areas and new endemic areas have emerged. This review summarises the recent literature relating to the effects of climatic factors on the incidence of HFRS in China and discusses future research directions. Temperature, precipitation and humidity affect crop yields, rodent breeding patterns and disease transmission, and these can be influenced by a changing climate. Detailed surveillance of infections caused by Hantaan and Seoul viruses and further research on the viral agents will aid in interpretation of spatiotemporal patterns and a better understanding of the environmental and ecological drivers of HFRS amid China's rapidly urbanising landscape and changing climate.

  3. Field measurement and analysis of climatic factors affecting dune mobility near Grand Falls on the Navajo Nation, southwestern United States

    Science.gov (United States)

    Bogle, Rian C.; Redsteer, Margaret Hiza; Vogel, John M.

    2015-01-01

    Aeolian sand covers extensive areas of the Navajo Nation in the southwestern United States. Much of this sand is currently stabilized by vegetation, although many drier parts of these Native lands also have active and partly active dunes. Current prolonged drought conditions that started in the mid-1990s are producing significant changes in dune mobility. Reactivation of regional aeolian deposits due to drought or increasing aridity from rising temperatures resulting from climate change could have serious consequences for human and animal populations, agriculture, grazing, and infrastructure. To understand and document the current and future potential for mobility, seasonally repeated surveys were used to track the location of multiple active barchan dunes. By utilizing Real-Time Kinematic GPS field surveys and simultaneously collecting in-situ meteorological data, it is possible to examine climatic parameters and seasonal variations that affect dune mobility and their relative influences. Through analysis of the recorded data, we examined the fit of various climate parameters, and demonstrate that under the current prolonged drought, wind power is the dominant factor controlling dune mobility.

  4. Controls of soil hydraulic characteristics on modeling groundwater recharge under different climatic conditions

    Science.gov (United States)

    Wang, Tiejun; Franz, Trenton E.; Zlotnik, Vitaly A.

    2015-02-01

    To meet the challenge of estimating spatially varying groundwater recharge (GR), increasing attention has been given to the use of vadose zone models (VZMs). However, the application of this approach is usually constrained by the lack of field soil hydraulic characteristics (SHCs) required by VZMs. To tackle this issue, SHCs based on the van Genuchten or Brooks-Corey model are generally estimated by pedotransfer functions or taken from texture based class averages. With the increasing use of this method, it is important to elucidate the controls of SHCs on computing GR mostly due to the high nonlinearity of the models. In this study, it is hypothesized that the nonlinear controls of SHCs on computing GR would vary with climatic conditions. To test this hypothesis, a widely used VZM along with two SHCs datasets for sand and loamy sand is used to compute GR at four sites in the continental Unites States with a significant gradient of precipitation (P). The simulation results show that the distribution patterns of mean annual GR ratios (GR ‾ / P ‾ , where GR ‾ and P ‾ are mean annual GR and P, respectively) vary considerably across the sites, largely depending on soil texture and climatic conditions at each site. It is found that GR ‾ / P ‾ is mainly controlled by the shape factor n in the van Genuchten model and the nonlinear effect of n on GR ‾ / P ‾ varies with climatic conditions. Specifically, for both soil textures, the variability in GR ‾ / P ‾ is smallest at the Andrews Forest with the highest P ‾ (191.3 cm/year) and GR ‾ / P ‾ is least sensitive to n; whereas, the variability in GR ‾ / P ‾ at the Konza Prairie (P ‾ = 84.2 cm/year) is the largest and GR ‾ / P ‾ is most sensitive to n. With further decreasing P ‾ , the nonlinear effect of n weakens at the Barta Brothers (P ‾ = 57.3 cm/year) and Sevilleta (P ‾ = 20.3 cm/year), leading to smaller GR ‾ / P ‾ variability at those two sites than at the Konza Prairie. The

  5. Socio-economic factors influencing climate change adaptation among crop farmers in Umuahia South Area of Abia State, Nigeria

    OpenAIRE

    N. O. Anyoha; F. N. Nnadi; J. Chikaire; J. A. Echetama; C. O. Utazi; R. A. Ihenacho

    2013-01-01

    The aim of the study was to determine the socioeconomic factors influencing climate change adaptation among crop farmers in Umuahia South Area of Abia State, Nigeria. The specific objectives of the study were to determine socioeconomic characteristics of crop farmers in the area, determine farmers level of awareness of climate change in the area, ascertain effects of climate change in crop production, identify adaptation strategies adopted by the farmers in the area and determine socioeconomi...

  6. Human factors in the control room

    International Nuclear Information System (INIS)

    The performance of Ontario Hydro's CANDU-based nuclear power plants has been excellent to date. Human factors engineering has been very much a part of the CANDU reactor design and development process. From the beginning operations staff has worked closely with designers. During commissioning and operation faults and errors are recorded and reported to the designers. A central group also carries out long-term evaluations of experience gained in nuclear plants around the world. The increasing complexity of nuclear power plants may in the short term increase operator's expectations for pay and job conditions, and in the longer term limit the number of people who want the job. Human factors engineering should minimize the complexity of systems, their interrelationships, the operator's tasks, and the environment in which they perform. Keep it simple

  7. The impact of climate factors on the prevalence of urolithiasis in Northern Taiwan

    Directory of Open Access Journals (Sweden)

    Kuo-Jen Lin

    2014-02-01

    Full Text Available Background: Urolithiasis is a common disease with high prevalence and recurrence. Its incidence varies in different geographic locations, and there are evidences that meteorological factors also affect urinary stone formation. The aim of this study is to analyze the effects of climate parameters on the numbers of shockwave treatments for urinary stones in our hospital, in order to understand the effects of these parameters on the prevalence of urolithiasis in northern Taiwan. Methods: We retrospectively reviewed the records of extracorporeal shockwave lithotripsy (ESWL performed in our hospital from December 2006 to November 2011. Repeated ESWL performed in the same patient within 1 month was excluded, and we only counted as one ESWL in our study. Climate data of the corresponding months were collected from Central Weather Bureau. The available monthly meteorological data included highest, lowest, and average temperatures, humidity, rainfall, total rain days, sunshine hours, average atmospheric pressure, and wind speed. Results: Monthly ESWL number was positively correlated to temperature (r = 0.696, sunshine hours (r = 0.515, and wind speed (r = 0.369, while it was negatively correlated to humidity (r = -0.441 and atmospheric pressure (r = -0.568. Average monthly temperature had the strongest correlation to ESWL number (r2 = 0.484. Monthly rainfall and rain days were not significantly correlated to ESWL number. To investigate the climate parameters together, we introduced these correlated factors into the multivariate linear regression model which demonstrated only temperature (ß = 1.438, 95% CI: 3.703-9.144, p < 0.001 and atmospheric pressure (ß = 0.803, 95% CI: 0.790-5.428, p = 0.010 to be independently related to monthly ESWL number. Conclusion: Temperature and atmospheric pressure are associated with monthly ESWL number. Ambient temperature is the most important climate factor affecting the prevalence of urolithiasis in northern Taiwan.

  8. Multi-Factor Impact Analysis of Agricultural Production in Bangladesh with Climate Change

    Science.gov (United States)

    Ruane, Alex C.; Major, David C.; Yu, Winston H.; Alam, Mozaharul; Hussain, Sk. Ghulam; Khan, Abu Saleh; Hassan, Ahmadul; Al Hossain, Bhuiya Md. Tamim; Goldberg, Richard; Horton, Radley M.; Rosenzweig, Cynthia

    2012-01-01

    Diverse vulnerabilities of Bangladesh's agricultural sector in 16 sub-regions are assessed using experiments designed to investigate climate impact factors in isolation and in combination. Climate information from a suite of global climate models (GCMs) is used to drive models assessing the agricultural impact of changes in temperature, precipitation, carbon dioxide concentrations, river floods, and sea level rise for the 2040-2069 period in comparison to a historical baseline. Using the multi-factor impacts analysis framework developed in Yu et al. (2010), this study provides new sub-regional vulnerability analyses and quantifies key uncertainties in climate and production. Rice (aman, boro, and aus seasons) and wheat production are simulated in each sub-region using the biophysical Crop Environment REsource Synthesis (CERES) models. These simulations are then combined with the MIKE BASIN hydrologic model for river floods in the Ganges-Brahmaputra-Meghna (GBM) Basins, and the MIKE21Two-Dimensional Estuary Model to determine coastal inundation under conditions of higher mean sea level. The impacts of each factor depend on GCM configurations, emissions pathways, sub-regions, and particular seasons and crops. Temperature increases generally reduce production across all scenarios. Precipitation changes can have either a positive or a negative impact, with a high degree of uncertainty across GCMs. Carbon dioxide impacts on crop production are positive and depend on the emissions pathway. Increasing river flood areas reduce production in affected sub-regions. Precipitation uncertainties from different GCMs and emissions scenarios are reduced when integrated across the large GBM Basins' hydrology. Agriculture in Southern Bangladesh is severely affected by sea level rise even when cyclonic surges are not fully considered, with impacts increasing under the higher emissions scenario.

  9. Drug treatment-related factors of inadequate seizure control.

    NARCIS (Netherlands)

    Handoko, K.B.; Rijkom, JE Zwart-van; Visee, H.F.; Hermens, W.A.; Hekster, Y.A.; Egberts, T.C.G.

    2008-01-01

    To optimize seizure control it is important to identify modifiable factors. We conducted a case-control study to explore to what extent drug treatment-related factors are associated with seizures. Eighty-six patients with epilepsy were evaluated: 45 cases (recently experienced a seizure) and 41 cont

  10. Distributed Lag Nonlinear Modelling Approach to Identify Relationship between Climatic Factors and Dengue Incidence in Colombo District, Sri Lanka

    Directory of Open Access Journals (Sweden)

    Thiyanga Talagala

    2015-12-01

    Full Text Available Dengue fever and its more severe deadly complication dengue hemorrhagic fever is an infectious mosquito borne disease. The rise in dengue fever has made a heavy economic burden to the country. Climate variability is considered as the major determinant of dengue transmission. Sri Lanka has a favorable climatic condition for development and transmission of dengue.  Hence the aim of this study is to estimate the effect of diverse climatic variables on the transmission of dengue while taking the lag effect and nonlinear effect into account. Weekly data on dengue cases were obtained from January, 2009 to September, 2014. Temperature, precipitation, visibility, humidity, and wind speed were also recorded as weekly averages. Poisson regression combined with distributed lag nonlinear model was used to quantify the impact of climatic factors. Results of  DLNM  revealed; Mean Temperature 250C – 270C at lag 1 – 8 weeks, Precipitation higher than  70mm at lag 1- 5 weeks and 20- 50mm at  lag 10 – 20 weeks, humidity ranged from 65% to 80% at lag 10 – 18 weeks, visibility greater than 14 km have a positive impact on the occurrence of dengue incidence while, mean temperature higher than 280C at lag 6 – 25 weeks, maximum temperature at lag 4 – 6 weeks, precipitation higher than 65mm at lag 15 – 20 weeks,  humidity less than 70% at lag 4 – 9 weeks, visibility less than 14km, high wind speed have a negative impact on the occurrence of dengue incidence. These findings can aid the targeting of vector control interventions and the planning for dengue vaccine implementation.

  11. Tectonic, lithologic and climatic controls on knickpoint retreat rates and landscape response times

    Science.gov (United States)

    Whittaker, Alexander; Boulton, Sarah; Kent, Emiko; Alçiçek, Cihat

    2016-04-01

    The plan-view and vertical rates at which transient knickpoints propagate through a landscape fundamentally controls geomorphic response times to tectonic and climatic perturbations. Here we present knickpoint retreat rates upstream of active faults for bedrock catchments in the Gediz graben of Turkey where past climate is well documented but where the history of faulting is not fully constrained. The rivers upstream of the normal fault-bounded graben each contain a non-lithologic knickpoint, including those that drain through inferred fault segment boundaries. Knickpoint heights measured vertically from the fault scale with footwall relief and documented fault throw (vertical displacement). Consequently, we deduce these knickpoints were initiated by an increase in slip rate on the basin-bounding fault, driven by linkage of the three main fault segments of the high-angle graben-bounding fault array. Fault interaction theory and ratios of channel steepness suggest that the slip rate enhancement factor on linkage was a factor of 3. We combine this information with geomorphic and structural constraints to estimate that linkage took place between 0.6 Ma and 1 Ma. Calculated pre- and post- linkage throw rates are 0.6 and 2 mm/yr respectively. Maximum plan-view knickpoint retreat rates upstream of the faults range from 4.5 to 28 mm/yr, and when normalised by drainage area, they are 2-7 times faster than for similar catchments upstream of normal faults in the Central Apennines of Italy and the Hatay Graben of Turkey. These knickpoint retreat rates imply a fluvial response time to fault growth and interaction of 1.6 to 2.7 My. However, marked along-strike disparities in retreat rates exist. We demonstrate that climate differences may explain the variation in rates between these study areas, but not within the Gediz graben itself. Consequently, we evaluate the extent to which measureable differences in bedrock lithology and erodibility modulate the propagation of

  12. Climate warming increases biological control agent impact on a non-target species

    OpenAIRE

    Lu, Xinmin; Siemann, Evan; He, Minyan; Wei, Hui; Shao, Xu; Ding, Jianqing

    2014-01-01

    Climate change may shift interactions of invasive plants, herbivorous insects and native plants, potentially affecting biological control efficacy and non-target effects on native species. Here, we show how climate warming affects impacts of a multivoltine introduced biocontrol beetle on the non-target native plant Alternanthera sessilis in China. In field surveys across a latitudinal gradient covering their full distributions, we found beetle damage on A. sessilis increased with rising tempe...

  13. Satellite-based assessment of climate controls on US burned area

    OpenAIRE

    D. C. Morton; G. J. Collatz; Wang, D.; Randerson, J. T.; Giglio, L.; Chen, Y.

    2013-01-01

    Climate regulates fire activity through the buildup and drying of fuels and the conditions for fire ignition and spread. Understanding the dynamics of contemporary climate–fire relationships at national and sub-national scales is critical to assess the likelihood of changes in future fire activity and the potential options for mitigation and adaptation. Here, we conducted the first national assessment of climate controls on US fire activity using two satellite-based estimates of monthly burne...

  14. An Integrated Control System for Heating and Indoor Climate Applications

    OpenAIRE

    Tahersima, Fatemeh

    2012-01-01

    In the present study, we investigated modeling and control of hydronic heat emitters integrated with a ground-source heat pump. Optimization of the system performance in terms of energy efficiency, associated energy cost and occupants' thermal comfort is the main objective to be fulfilled via de-sign of an integrated controller. We also proposed control strategies to manage energy consumption of the building to turn domestic heat demands into a flexible load in the smart electricity grid. We ...

  15. Policy means of control in the climate policy

    International Nuclear Information System (INIS)

    Using the MARKAL simulation tool, different economic incentives in climate mitigation policy such as tradable emission permits, green certificates and carbon dioxide taxes have been analyzed. The analysis shows that there is an important advantage in applying the emission reductions internationally compared to a national policy, due to the varying marginal costs for the measures in different countries. The analysis also reveals at which price levels the Nordic countries as a whole become net sellers or net buyers of emission permits. The effects of combining emission permits with green certificates are analyzed, e.g. the inverse relation between permit and certificate prices. An appendix to the report gives a description of the Swedish energy system, emissions world-wide and examples of cost-effective mitigation measures for Sweden

  16. Reproductive Risk Factors for Breast Cancer: A Case Control Study

    OpenAIRE

    Meshram II; Hiwarkar PA; Kulkarni PN

    2009-01-01

    Background: Breast cancer is second most important cancer among Indian women. Although risk factors are not much prevalent as in western countries, incidence rate is increasing in India. The study was undertaken to study various risk factors associated with breast cancer. Methods: A hospital based group matched case control study was undertaken to identify risk factors. The study consisted of 105 hospitalized cases confirmed on histopathology and 210 group matched controls selected from urban...

  17. Chemical weathering as a mechanism for the climatic control of bedrock river incision.

    Science.gov (United States)

    Murphy, Brendan P; Johnson, Joel P L; Gasparini, Nicole M; Sklar, Leonard S

    2016-04-14

    Feedbacks between climate, erosion and tectonics influence the rates of chemical weathering reactions, which can consume atmospheric CO2 and modulate global climate. However, quantitative predictions for the coupling of these feedbacks are limited because the specific mechanisms by which climate controls erosion are poorly understood. Here we show that climate-dependent chemical weathering controls the erodibility of bedrock-floored rivers across a rainfall gradient on the Big Island of Hawai'i. Field data demonstrate that the physical strength of bedrock in streambeds varies with the degree of chemical weathering, which increases systematically with local rainfall rate. We find that incorporating the quantified relationships between local rainfall and erodibility into a commonly used river incision model is necessary to predict the rates and patterns of downcutting of these rivers. In contrast to using only precipitation-dependent river discharge to explain the climatic control of bedrock river incision, the mechanism of chemical weathering can explain strong coupling between local climate and river incision.

  18. Climate Change

    Science.gov (United States)

    ... in a place over a period of time. Climate change is major change in temperature, rainfall, snow, or ... by natural factors or by human activities. Today climate changes are occurring at an increasingly rapid rate. Climate ...

  19. Climate change as a confounding factor in reversibility of acidification: RAIN and CLIMEX projects

    Directory of Open Access Journals (Sweden)

    R. F. Wright

    2001-01-01

    Full Text Available The RAIN and CLIMEX experiments at Risdalsheia, southernmost Norway, together cover 17 years (1984-2000 of whole-catchment manipulation of acid deposition and climate. A 1200 m2 roof placed over the forest canopy at KIM catchment excluded about 80% of ambient acid deposition; clean rain was sprinkled under the roof. A climate change treatment (3.7°C increase in air temperature and increase in air carbon dioxide concentrations to 560 ppmv was superimposed on the clean rain treatment for four years (1995-1998. Sea-salt inputs and temperature are climate-related factors that influence water chemistry and can confound long-term trends caused by changes in deposition of sulphur and nitrogen. The RAIN and CLIMEX experiments at Risdalsheia provided direct experimental data that allow quantitative assessment of these factors. Run-off chemistry responded rapidly to the decreased acid deposition. Sulphate concentrations decreased by 50% within three years; nitrate and ammonium concentrations decreased to new steady-state levels within the first year. Acid neutralising capacity increased and hydrogen ion and inorganic aluminium decreased. Similar recovery from acidification was also observed at the reference catchment, ROLF, in response to the general 50% reduction in sulphate deposition over southern Norway in the late 1980s and 1990s. Variations in sea-salt deposition caused large variations in run-off chemistry at the reference catchment ROLF and the year-to-year noise in acid neutralising capacity was as large as the overall trend over the period. These variations were absent at KIM catchment because the sea-salt inputs were held constant over the entire 17 years of the clean rain treatment. The climate change experiment at KIM catchment resulted in increased leaching of inorganic nitrogen, probably due to increased mineralisation and nitrification rates in the soils. Keywords: acid deposition, global change, water, soil, catchment, experiment, Norway.

  20. Underlying Factors for Practicality of the Production Control Systems

    DEFF Research Database (Denmark)

    Arica, Emrah; Strandhagen, Jan Ola; Hvolby, Hans-Henrik

    2012-01-01

    This paper gives indications to important factors that must be considered for effectiveness of the production control systems under uncertainty. Five key factors have been identified by the literature study. Production schedule generation and execution approach under uncertainty, information...... and communication technology, coordination and feedback, human factors and decision making, and measurement are the identified factors to be taken into account. Industrial interviews with three case companies, that are participating to the research program called The Norwegian Manufacturing Future (SFI NORMAN...

  1. Numerical investigation of climate factors impact on carbon cycle in the East Asian terrestrial ecosystem

    Energy Technology Data Exchange (ETDEWEB)

    Mabuchi, K. [Meteorological Research Institute, Tsukuba (Japan); Takahashi, K. [Japan Meteorological Agency, Tokyo (Japan); Nasahara, K.N. [Univ. of Tsukuba (Japan). Inst. of Agricultural and Forest Engineering

    2009-07-01

    The present state of environmental problems due to global warming resulting from increases of greenhouse gases has reached new levels. The international treaty known as the United Nations Framework Convention on Climate Change (UNFCCC) was adopted in 1992 to begin to consider what can be done to reduce global warming. The Kyoto Protocol, adopted in 1997 at the third Conference of the Parties to the UNFCCC (COP 3), proposed a worldwide reduction of greenhouse gas emission. Under these conditions, it became necessary to monitor the increases of greenhouse gases, especially carbon dioxide, and to conduct research to further understand the mechanisms of interactions between environmental changes and the carbon balance. Estimations of the carbon dioxide budget are of great importance in taking the proper steps to deal with increased concentrations due to anthropogenic emissions, and in predictions of future concentration levels. The main components of the carbon dioxide budget are anthropogenic emissions, atmospheric concentration, the exchange between the atmosphere and ocean, and the exchange between the atmosphere and terrestrial ecosystems. Among these components, the role of the terrestrial ecosystem is still uncertain, due to the heterogeneity of that system. Using a regional climate model that includes a terrestrial biosphere model, numerical simulations were performed to clarify the mechanism of the carbon cycle between the terrestrial ecosystem and the atmosphere and to investigate the climate factors impact on the carbon cycle in the East Asian terrestrial ecosystem. Model verifications were performed with regard to the principal elements: precipitation and vegetation phenology. The variations of the atmospheric carbon dioxide concentration simulated by the model were validated using the data at six in situ observatories. After the confirmations of the model performance, regional features of the impact of climate factors on the gross primary production (GPP

  2. Use of a Regional Climate Model to Diagnose Circulation and Surface Climate Controls of Wildfire in North America

    Science.gov (United States)

    Hostetler, S. W.; Bartlein, P. J.; Alder, J. R.

    2014-12-01

    We explore monthly North American climate and wildfire relationships through joint analysis of a new wildfire data base and climate simulations that we conducted with the RegCM3 regional climate model. We derived the new data base, which covers 1986-2012, by screening and merging the US FPA-FOD, US NIFC and Canadian CNFDB data guided by an analysis that included the examination of "heavy-tailed" statistical distributions (Pareto and tapered Pareto) in order to maximize the number of combined records while minimizing potential irregularities and noise such as over- and under-reporting and spurious data. We associate area burned from lightning-set wildfires, as registered to the start date of the fires, with the simulated atmospheric circulation and the surface water and energy balances at 50 km over NA and at 15 km for 4 sub-regions of NA. Our 50-km results clearly associate the seasonal cycle and spatial distribution of wildfire in the US and Canada with the seasonal cycle of atmospheric circulation and surface climate, in particular to solar and long-wave radiation and latent and sensible heating. We also use the 50-km model output to diagnose the within-season temporal and spatial characteristics of wildfire (e.g., the Northern Rockies versus the Boreal forest) and the characteristics of individual fire years. Over the 15-km sub-regions, we use composite anomalies of the surface water and energy balances to differentiate the spatial and temporal controls of high- and low-fire years and to assess the role of interannual variability in the fire record

  3. Microbial responses to multi-factor climate change: Effects on soil enzymes

    Directory of Open Access Journals (Sweden)

    J Megan Steinweg

    2013-06-01

    Full Text Available The activities of extracellular enzymes, the proximate agents of decomposition in soils, are known to depend strongly on temperature, but less is known about how they respond to changes in precipitation patterns, and the interaction of these two components of climate change. Both enzyme production and turnover can be affected by changes in temperature and soil moisture, thus it is difficult to predict how enzyme pool size may respond to altered climate. Soils from the Boston-Area Climate Experiment, which is located in an old field (on abandoned farmland, were used to examine how climate variables affect enzyme activities and microbial biomass carbon (MBC in different seasons and in soils exposed to a combination of three levels of precipitation treatments (ambient, 150% of ambient during growing season, and 50% of ambient year-round and four levels of warming treatments (unwarmed to ~4˚C above ambient over the course of a year. Warming, precipitation and season had very little effect on potential enzyme activity. Most models assume that enzyme dynamics follow microbial biomass, because enzyme production should be directly controlled by the size and activity of microbial biomass. We observed differences among seasons and treatments in mass-specific potential enzyme activity, suggesting that this assumption is invalid. In June 2009, mass-specific potential enzyme activity, using chloroform fumigation-extraction MBC, increased with temperature, peaking under medium warming and then declining under the highest warming. This finding suggests that either enzyme production increased with temperature or turnover rates decreased. Increased maintenance costs associated with warming may have resulted in increased mass-specific enzyme activities due to increased nutrient demand. Our research suggests that allocation of resources to enzyme production could be affected by climate-induced changes in microbial efficiency and maintenance costs.

  4. Risk factors for caries - control and prevention

    Directory of Open Access Journals (Sweden)

    Melida Hasanagić

    2008-08-01

    Full Text Available Objectives. To investigate a prevalence of caries, filled permanentand extracted permanent teeth, as well as caries risk factors inschool children aged 7, 9 and 11.Methods. The survey included 800 children (296 children aged7; 254 children aged 9 and 250 children aged 11 from the MostarMunicipality, 400 of them living in both rural and urban areas.A dental mirror and standard light of dental chair were used forexamination. The DMF index (Dental Caries, Missing Teeth andFilled Teeth was determined, as well as failure in keeping teethhygiene, sugar intake with food, and incidence of oral cavity infection.Results. The dental state of permanent teeth in children aged 7and 9 has shown significant difference between the children fromrural and urban areas (p < 0,001. Out of 2,698 and 2,790 permanentteeth in children aged 11 from rural and urban areas, 1,086(40,25 % and 884 (31.68 % had caries, respectively (p < 0.01.The difference between these groups of children has been foundin relation to the index of oral hygiene too (p < 0.05.Conclusion. An identification of risk groups for getting caries wasvery important and could help health and social structures to maintaintheir programs in order to improve oral health.

  5. Spatio-temporal variation in vegetation biomass and its relationships with climate factors in the Xilingol grasslands, Northern China.

    Directory of Open Access Journals (Sweden)

    Tian Gao

    Full Text Available Knowledge about grassland biomass and its dynamics is critical for studying regional carbon cycles and for the sustainable use of grassland resources. In this study, we investigated the spatio-temporal variation of biomass in the Xilingol grasslands of northern China. Field-based biomass samples and MODIS time series data sets were used to establish two empirical models based on the relationship of the normalized difference vegetation index (NDVI with above-ground biomass (AGB as well as that of AGB with below-ground biomass (BGB. We further explored the climatic controls of these variations. Our results showed that the biomass averaged 99.01 Tg (1 Tg=10(12 g over a total area of 19.6 × 10(4 km(2 and fluctuated with no significant trend from 2001 to 2012. The mean biomass density was 505.4 g/m(2, with 62.6 g/m(2 in AGB and 442.8 g/m(2 in BGB, which generally decreased from northeast to southwest and exhibited a large spatial heterogeneity. The year-to-year AGB pattern was generally consistent with the inter-annual variation in the growing season precipitation (GSP, showing a robust positive correlation (R(2=0.82, P<0.001, but an opposite coupled pattern was observed with the growing season temperature (GST (R(2=0.61, P=0.003. Climatic factors also affected the spatial distribution of AGB, which increased progressively with the GSP gradient (R(2=0.76, P<0.0001 but decreased with an increasing GST (R(2=0.70, P<0.0001. An improved moisture index that combined the effects of GST and GSP explained more variation in AGB than did precipitation alone (R(2=0.81, P<0.0001. The relationship between AGB and GSP could be fit by a power function. This increasing slope of the GSP-AGB relationships along the GSP gradient may be partly explained by the GST-GSP spatial pattern in Xilingol. Our findings suggest that the relationships between climatic factors and AGB may be scale-dependent and that multi-scale studies and sufficient long-term field data are needed

  6. How phosphorus limitation can control climatic gas emission

    Science.gov (United States)

    Gypens, Nathalie; Borges, Alberto V.; Speeckaert, Gaelle; Ghyoot, Caroline

    2015-04-01

    Anthropogenic activities severely increased river nutrient [nitrogen (N) and phosphorus (P)] loads to European coastal areas. However, specific nutrient reduction policies implemented since the late 1990's have considerably reduced P loads, while N is maintained. In the Southern North Sea, the resulting N: P: Si imbalance (compared to phytoplankton requirements) stimulated the growth of Phaeocystis colonies modifying the functioning of the ecosystem and, therefore, the carbon cycle but also the biogenic sulphur cycle, Phaeocystis being a significant producer of DMSP (dimethylsulphide propionate), the precursor of dimethylsulfide (DMS). In this application, the mechanistic MIRO-BIOGAS model is used to investigate the effects of changing N and P loads on ecosystem structure and their impact on DMS and CO2 emissions. In particular, competition for P between phytoplankton groups (diatoms vs Phaeocystis colonies) but also between phytoplankton and bacteria is explored. The ability of autotroph and heterotroph organism to use dissolved organic phosphorus (DOP) as P nutrient source is also explored and its effect on climatic gas emission estimated. Simulations were done from 1950 to 2010 and different nutrient limiting conditions are analyzed.

  7. Ecological interaction between insect pests, climatic factors and plant traits on abundance of beneficial insects in paddy field

    Directory of Open Access Journals (Sweden)

    Norazliza, R.

    2016-04-01

    Full Text Available The presences of beneficial insects in the paddy field are very important for the ecological systems of paddy field as those insects could help managing the population of the pests. Hence, it will reduce the dependence on pesticides usage to combat the population of insect pests. This study was aimed to study on ecological interaction between environmental factors such as insect pests, plant height, rainfall, temperature and humidity with abundance of beneficial insects in paddy field of Sungai Burong, Tanjung Karang, Selangor for two seasons of paddy planting. Low number of insects composition were recorded in paddy field at Sungai Burong during the vegetative phase and highest during the reproductive and maturity phases for two seasons of paddy planting. The trend of mean composition of insects were gradually increasing from vegetative to maturity phases while, the ecological interaction between insect pests, climatic factors and plant traits were acceptable as good predictor for all beneficial insects collected in this study namely Zygoptera, Gerridae, Coccinellidae and Staphylinidae except for Anisoptera. Therefore, consideration on several stated factors by maintaining or conserving ecology and controlling practices in good manner in paddy field has high potential and more reliable to control insect pests effectively using beneficial insects.

  8. Impact of Climate and Environmental Factors on West Nile Virus Circulation in Iran

    Directory of Open Access Journals (Sweden)

    Farzaneh Ahmadnejad

    2016-01-01

    Full Text Available Background: Geographic distribution of West Nile virus (WNV is heterogeneous in Iran by a high circulation in the southern-western areas. The objective of our study was to determine environmental and climatic factors associ­ated with the risk of WNV equine seropositivity in Iran.Methods: Serological data were obtained from a serosurvey conducted in equine population in 260 districts in Iran. The climate and environmental parameters included in the models were distance to the nearest wetland area, type of stable, Normalized Difference Vegetation Index (NDVI, annual mean temperature, humidity and precipitation.Results: The important risk factors included annual mean temperature, distance to wetlands, local and seasonal NDVI differences. The effect of local NDVI differences in spring was particularly notable. This was a normalized difference of average NDVI between two areas: a 5 km radius area centered on the stable and the 5–10 km sur­rounding area.Conclusion: The model indicated that local NDVI’s contrast during spring is a major risk factor of the transmission of West-Nile virus in Iran. This so-called oasis effect consistent with the seasonal production of vegetation in spring, and is associated to the attractiveness of the local NDVI environment for WNV vectors and hosts.  

  9. Quantitative Analysis of Critical Factors for the Climate Impact of Landfill Mining.

    Science.gov (United States)

    Laner, David; Cencic, Oliver; Svensson, Niclas; Krook, Joakim

    2016-07-01

    Landfill mining has been proposed as an innovative strategy to mitigate environmental risks associated with landfills, to recover secondary raw materials and energy from the deposited waste, and to enable high-valued land uses at the site. The present study quantitatively assesses the importance of specific factors and conditions for the net contribution of landfill mining to global warming using a novel, set-based modeling approach and provides policy recommendations for facilitating the development of projects contributing to global warming mitigation. Building on life-cycle assessment, scenario modeling and sensitivity analysis methods are used to identify critical factors for the climate impact of landfill mining. The net contributions to global warming of the scenarios range from -1550 (saving) to 640 (burden) kg CO2e per Mg of excavated waste. Nearly 90% of the results' total variation can be explained by changes in four factors, namely the landfill gas management in the reference case (i.e., alternative to mining the landfill), the background energy system, the composition of the excavated waste, and the applied waste-to-energy technology. Based on the analyses, circumstances under which landfill mining should be prioritized or not are identified and sensitive parameters for the climate impact assessment of landfill mining are highlighted. PMID:27282202

  10. Identification of dominant climate factor for pan evaporation trend in the Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    LIU Xiaomang; ZHENG Hongxing; ZHANG Minghua; LIU Changming

    2011-01-01

    Despite the observed increase in global temperature,observed pan evaporation in many regions has been decreasing over the past 50 years,which is known as the “pan evaporation paradox”.The “pan evaporation paradox” also exists in the Tibetan Plateau,where pan evaporation has decreased by 3.06 mm a-2 (millimeter per annum).It is necessary to explain the mechanisms behind the observed decline in pan evaporation because the Tibetan Plateau strongly influences climatic and environmental changes in China,Asia and even in the Northern Hemisphere.In this paper,a derivation based approach has been used to quantitatively assess the contribution rate of climate factors to the observed pan evaporation trend across the Tibetan Plateau.The results showed that,provided the other factors remain constant,the increasing temperature should have led to a 2.73 mm a-2 increase in pan evaporation annually,while change in wind speed,vapor pressure and solar radiation should have led to a decrease in pan evaporation by 2.81 mm a-2,1.96 mm a-2 and 1.11 mm a-2 respectively from 1970 to 2005.The combined effects of the four climate variables have resuited in a 3.15 mm a-2 decrease in pan evaporation,which is close to the observed pan evaporation trend with a relative error of 2.94%.A decrease in wind speed was the dominant factor for the decreasing pan evaporation,followed by an increasing vapor pressure and decreasing solar radiation,all of which offset the effect of increasing temperature across the Tibetan Plateau.

  11. PMBLDC motor drive with power factor correction controller

    DEFF Research Database (Denmark)

    George, G.J.; Ramachandran, Rakesh; Arun, N.

    2012-01-01

    This paper presents a boost converter configuration, control scheme and design of single phase power factor controller for permanent magnet brushless DC motor (PMBLDCM) drive. PMBLDC motors are the latest choice of researchers, due to the high efficiency, silent operation, compact size, high...... reliability, and low maintenance requirements. The proposed Power Factor Controller topology improves power quality by improving performance of PMBLDCM drive, such as reduction of AC main current harmonics, near unity power factor. PFC converter forces the drive to draw sinusoidal supply current in phase...

  12. CLIMATE CHANGES AS THE RISK FACTOR IN MILK PRODUCTION IN WIELKOPOLSKA

    Directory of Open Access Journals (Sweden)

    Ryszard Chaberski

    2015-06-01

    Full Text Available The pilot researches were conducted in Wielkopolska. They aimed initial identifi cation of cows reaction on changing of THI, which are likened to temperature and humidity conditions of air. The subjected cows characterize with high productivity, exceeding 40kg of milk per day, independently from lactation stages. The results display that the day s production of raw milk, as well as fat and protein content, do not only depend on lactation stage but also on the value of THI factors. Higher THI is accompanied by loss in the weight of milk and drop in its technological utility. The climate warming may escalate the risk of production loss during the heats.

  13. Why natural gas for CO2 and climate control?

    International Nuclear Information System (INIS)

    The Intergovernmental Panel on Climate Change (IPCC) and the US Environmental Protection Agency (EPA) have suggested that increased use of natural gas is a possible strategy for reducing the potential for global warming. Carbon dioxide (CO2) contributes as much to global warming as all other greenhouse gases combined. During combustion, natural gas generates less CO2 per unit of energy produced than either coal or oil. On the basis of the amount of CO2 emitted, the potential for global warming could be reduced by substituting natural gas to coal or oil. However, since natural gas is primarily methane, a potent greenhouse gas, these emissions could reduce natural gas's inherent advantage of lower CO2 emissions. To address this issue and compare the fuels on an equivalent basis, it is necessary to account for emissions of all greenhouse gases throughout the fuel cycle of each fuel and to determine the impact of these gases on global warming. Gas Research Institute and EPA jointly funded a study to quantify methane emissions from the natural gas industry so that this information could be used as input to address the issue of the fuel switching strategy. The study found that the natural gas industry emitted 1.4% of natural gas production (314 Bscf of methane) to the atmosphere in 1992. Today, due to voluntary reductions from the gas industry, the percent leaked is even less. This 1992 amount has been analyzed over a broad range of global warming potentials, and the conclusion that fuel switching to natural gas reduces the potential for global warming is supported. The results of this study are presented in this paper

  14. Vulnerability to extreme heat and climate change: is ethnicity a factor?

    Directory of Open Access Journals (Sweden)

    Alana Hansen

    2013-07-01

    Full Text Available Background: With a warming climate, it is important to identify sub-populations at risk of harm during extreme heat. Several international studies have reported that individuals from ethnic minorities are at increased risk of heat-related illness, for reasons that are not often discussed. Objective: The aim of this article is to investigate the underpinning reasons as to why ethnicity may be associated with susceptibility to extreme heat, and how this may be relevant to Australia's population. Design: Drawing upon literary sources, the authors provide commentary on this important, yet poorly understood area of heat research. Results: Social and economic disparities, living conditions, language barriers, and occupational exposure are among the many factors contributing to heat-susceptibility among minority ethnic groups in the United States. However, there is a knowledge gap about socio-cultural influences on vulnerability in other countries. Conclusion: More research needs to be undertaken to determine the effects of heat on tourists, migrants, and refugees who are confronted with a different climatic environment. Thorough epidemiological investigations of the association between ethnicity and heat-related health outcomes are required, and this could be assisted with better reporting of nationality data in health statistics. Climate change adaptation strategies in Australia and elsewhere need to be ethnically inclusive and cognisant of an upward trend in the proportion of the population who are migrants and refugees.

  15. Meteorological Factors for Dengue Fever Control and Prevention in South China

    Science.gov (United States)

    Gu, Haogao; Leung, Ross Ka-Kit; Jing, Qinlong; Zhang, Wangjian; Yang, Zhicong; Lu, Jiahai; Hao, Yuantao; Zhang, Dingmei

    2016-01-01

    Dengue fever (DF) is endemic in Guangzhou and has been circulating for decades, causing significant economic loss. DF prevention mainly relies on mosquito control and change in lifestyle. However, alert fatigue may partially limit the success of these countermeasures. This study investigated the delayed effect of meteorological factors, as well as the relationships between five climatic variables and the risk for DF by boosted regression trees (BRT) over the period of 2005–2011, to determine the best timing and strategy for adapting such preventive measures. The most important meteorological factor was daily average temperature. We used BRT to investigate the lagged relationship between dengue clinical burden and climatic variables, with the 58 and 62 day lag models attaining the largest area under the curve. The climatic factors presented similar patterns between these two lag models, which can be used as references for DF prevention in the early stage. Our results facilitate the development of the Mosquito Breeding Risk Index for early warning systems. The availability of meteorological data and modeling methods enables the extension of the application to other vector-borne diseases endemic in tropical and subtropical countries. PMID:27589777

  16. Meteorological Factors for Dengue Fever Control and Prevention in South China.

    Science.gov (United States)

    Gu, Haogao; Leung, Ross Ka-Kit; Jing, Qinlong; Zhang, Wangjian; Yang, Zhicong; Lu, Jiahai; Hao, Yuantao; Zhang, Dingmei

    2016-01-01

    Dengue fever (DF) is endemic in Guangzhou and has been circulating for decades, causing significant economic loss. DF prevention mainly relies on mosquito control and change in lifestyle. However, alert fatigue may partially limit the success of these countermeasures. This study investigated the delayed effect of meteorological factors, as well as the relationships between five climatic variables and the risk for DF by boosted regression trees (BRT) over the period of 2005-2011, to determine the best timing and strategy for adapting such preventive measures. The most important meteorological factor was daily average temperature. We used BRT to investigate the lagged relationship between dengue clinical burden and climatic variables, with the 58 and 62 day lag models attaining the largest area under the curve. The climatic factors presented similar patterns between these two lag models, which can be used as references for DF prevention in the early stage. Our results facilitate the development of the Mosquito Breeding Risk Index for early warning systems. The availability of meteorological data and modeling methods enables the extension of the application to other vector-borne diseases endemic in tropical and subtropical countries. PMID:27589777

  17. Climate control in cultural heritage buildings in Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, Poul Klenz [The National Museum, Copenhagen (Denmark). Dept. of Conservation; Brostroem, Tor [Gotland Univ., Visby (Sweden)

    2011-07-01

    Conservation heating has been used for decades to control the RH in cultural heritage buildings. But if the building is not used for living or working, heating is not needed for human comfort. The chemical decay of organic materials depends mainly on temperature, so it is better for preservation to reduce heating. The air exchange rate is related to the design of the building envelope. With rising energy prices humidity control by dehumidification may be an attractive alternative. The potential for energy efficient RH control was examined for a generic building exposed to the monthly average outside temperature and RH in Denmark. The indoor temperature was allowed to follow the outside average, whereas the indoor RH was controlled to 40 % 50 % 60 % or 70 %. Dehumidification was implemented in three different buildings: A recent museum store, a medieval church, and an 18th century country mansion. The energy consumption depends on the RH set point, the air exchange rate and the source of liquid moisture to the building. The air exchange rate related to the design of the building envelope. Single glazed windows and doors are the most important sources of leakage to buildings. Lack of maintenance may lead to poor performance of the dehumidifier and waste energy. (orig.)

  18. Individual and collective climate control in aircraft cabins

    NARCIS (Netherlands)

    Jacobs, P.; Gids, W.F. de

    2006-01-01

    A new concept for aircraft cabin climatisation has been developed in which the seat is the main Indoor Air Quality (IAQ) and temperature control system for the passengers containing provisions for local supply and local exhaust of air. Direct supply of clean outside air in the breathing zone, throug

  19. Correlation and periodicity analysis between herbage yields and climatic factors in the Tianshan Mountain,China in 22 year periods.

    Science.gov (United States)

    Jianlong, L.

    2009-04-01

    To analyze the relationship between herbage yields and climatic factors, 22 years of herbage yields and climate data were collected on the northern slope of the Tianshan Mountains region of western China. Using multiple regression analysis, maximum entropy spectrum analysis and cross spectrum analysis, it was clarified that fluctuation of climatic factors affected herbage yields and their periodical variation. The herbage yields were correlated significantly to the four climate factors including annual precipitation, annual means of relative humidity, absolute humidity and percentage of sunshine, but unrelated to the trend variable (the former year yield has little effects on the later) and other climatic factors. These clarified that long term variation of grassland productivity responded directly to changes of some climate factors in typical zone of arid continental climate. The results in co-spectrum and quadrature spectrum analysis revealed that the herbage yields had 4-year period similar to some moisture factors, and with 1/4 period delay. These findings demonstrated further that the fluctuation of some climatic elements (precipitation particularly) was the crucial factor affecting the variations of herbage yields of natural grassland in arid and semiarid ecosystem. The periodical change of vegetation and correlation with climate provide us a way to predict the herbage production according to the climate change, and it was important for the herdsmen to arrange predictively their animal production including rectifying their livestock population in natural grazing land and storing up the supply of forage timely for livestock use in cold season. Our finding in periodical variation of climatic element and plant yield further demonstrated the crucial driver of some climate factors on formation of herbage yields. The same or similar quasi-4-year period in climatic element and vegetation was due to that periodical variation of climatic element (especially

  20. Climatic control of tracheid production of black spruce in dense mesic stands of eastern Canada.

    Science.gov (United States)

    Dufour, Boris; Morin, Hubert

    2013-02-01

    Inferences on climate change effects are reliable only if they are based on a causal relationship rather than simple statistical predictive capacity. To assess for causal links between climate and mature black spruce (Picea mariana (Mills.) BSP) radial growth, we combined the use of wood anatomy, cambium phenology, climate and soil measurements (air temperature and humidity, precipitations, soil temperature and water content, photosynthetically active radiation), and a model selection approach proceeding backwards from a full model. Results show that the number of tracheids is responsible for 88% of the variation in ring width whereas mean tracheid diameter accounts for the remaining 12%. The number of tracheids produced depends on factors related to photosynthesis during tracheid production, i.e., daily light intensity and maximum temperature between the day of initiation and the day of cessation of tracheid production, plus soil temperature during August of the previous year which is an important period for determining the number of new needles produced. It is also important to consider duration of the period for tracheid production. These results imply that short-term climate change should increase black spruce radial growth. They also suggest that the typical use of post-growth ring width sampling individually linked to air temperature and precipitations is not sufficient to infer climate change effects accurately on radial growth where there is no strong single climatic limitation but multiple limitations instead. PMID:23355635

  1. A broad assessment of factors determining Culicoides imicola abundance: modelling the present and forecasting its future in climate change scenarios.

    Directory of Open Access Journals (Sweden)

    Pelayo Acevedo

    Full Text Available Bluetongue (BT is still present in Europe and the introduction of new serotypes from endemic areas in the African continent is a possible threat. Culicoides imicola remains one of the most relevant BT vectors in Spain and research on the environmental determinants driving its life cycle is key to preventing and controlling BT. Our aim was to improve our understanding of the biotic and abiotic determinants of C. imicola by modelling its present abundance, studying the spatial pattern of predicted abundance in relation to BT outbreaks, and investigating how the predicted current distribution and abundance patterns might change under future (2011-2040 scenarios of climate change according to the Intergovernmental Panel on Climate Change. C. imicola abundance data from the bluetongue national surveillance programme were modelled with spatial, topoclimatic, host and soil factors. The influence of these factors was further assessed by variation partitioning procedures. The predicted abundance of C. imicola was also projected to a future period. Variation partitioning demonstrated that the pure effect of host and topoclimate factors explained a high percentage (>80% of the variation. The pure effect of soil followed in importance in explaining the abundance of C. imicola. A close link was confirmed between C. imicola abundance and BT outbreaks. To the best of our knowledge, this study is the first to consider wild and domestic hosts in predictive modelling for an arthropod vector. The main findings regarding the near future show that there is no evidence to suggest that there will be an important increase in the distribution range of C. imicola; this contrasts with an expected increase in abundance in the areas where it is already present in mainland Spain. What may be expected regarding the future scenario for orbiviruses in mainland Spain, is that higher predicted C. imicola abundance may significantly change the rate of transmission of orbiviruses.

  2. Climate warming increases biological control agent impact on a non-target species.

    Science.gov (United States)

    Lu, Xinmin; Siemann, Evan; He, Minyan; Wei, Hui; Shao, Xu; Ding, Jianqing

    2015-01-01

    Climate change may shift interactions of invasive plants, herbivorous insects and native plants, potentially affecting biological control efficacy and non-target effects on native species. Here, we show how climate warming affects impacts of a multivoltine introduced biocontrol beetle on the non-target native plant Alternanthera sessilis in China. In field surveys across a latitudinal gradient covering their full distributions, we found beetle damage on A. sessilis increased with rising temperature and plant life history changed from perennial to annual. Experiments showed that elevated temperature changed plant life history and increased insect overwintering, damage and impacts on seedling recruitment. These results suggest that warming can shift phenologies, increase non-target effect magnitude and increase non-target effect occurrence by beetle range expansion to additional areas where A. sessilis occurs. This study highlights the importance of understanding how climate change affects species interactions for future biological control of invasive species and conservation of native species.

  3. Climate warming increases biological control agent impact on a non-target species

    Science.gov (United States)

    Lu, Xinmin; Siemann, Evan; He, Minyan; Wei, Hui; Shao, Xu; Ding, Jianqing

    2015-01-01

    Climate change may shift interactions of invasive plants, herbivorous insects and native plants, potentially affecting biological control efficacy and non-target effects on native species. Here, we show how climate warming affects impacts of a multivoltine introduced biocontrol beetle on the non-target native plant Alternanthera sessilis in China. In field surveys across a latitudinal gradient covering their full distributions, we found beetle damage on A. sessilis increased with rising temperature and plant life history changed from perennial to annual. Experiments showed that elevated temperature changed plant life history and increased insect overwintering, damage and impacts on seedling recruitment. These results suggest that warming can shift phenologies, increase non-target effect magnitude and increase non-target effect occurrence by beetle range expansion to additional areas where A. sessilis occurs. This study highlights the importance of understanding how climate change affects species interactions for future biological control of invasive species and conservation of native species. PMID:25376303

  4. [Spatial distribution characteristics of China cotton fiber quality and climatic factors based on GIS].

    Science.gov (United States)

    Xiong, Zong-Wei; Gu, Sheng-Hao; Mao, Li-Li; Wang, Xue-Jiao; Zhang, Li-Zhen; Zhou, Zhi-Guo

    2012-12-01

    By using geographical information system (GIS), the cotton fiber quality data from 2005 to 2011 and the daily meteorological data from 1981 to 2010 at 82 sites (counties and cities) in China major cotton production regions were collected and treated with spatial interpolation. The spatial information system of cotton fiber quality in China major cotton production regions was established based on GIS, and the spatial distribution characteristics of the cotton fiber quality and their relationships with the local climatic factors were analyzed. In the northwest region (especially Xinjiang) of China, due to the abundant sunlight, low precipitation, and low relative humidity, the cotton fiber length, micronaire, and grade ranked the first. In the Yangtze River region and Yellow River region, the specific strength of cotton fiber was higher, and in the Yangtze River region, the cotton fiber length and specific strength were higher, while the micronaire and grade were lower than those in the Yellow River region. The cotton fiber quality was closely related to the climate factors such as temperature, sunlight, rainfall, and humidity.

  5. Carbon exchange between ecosystems and atmosphere in the Czech Republic is affected by climate factors

    Energy Technology Data Exchange (ETDEWEB)

    Marek, Michal V., E-mail: marek.mv@czechglobe.cz [Global Change Research Centres, Academy of Science of the Czech Republic, Belidla 4a CZ-60300 Brno (Czech Republic); Institute of Forest Ecology Forestry Faculty, Mendel University Brno, Zemedelska 3, CZ-614 00 (Czech Republic); Janous, Dalibor; Taufarova, Klara; Havrankova, Katerina; Pavelka, Marian; Kaplan, Veroslav [Global Change Research Centres, Academy of Science of the Czech Republic, Belidla 4a CZ-60300 Brno (Czech Republic); Markova, Irena [Institute of Forest Ecology Forestry Faculty, Mendel University Brno, Zemedelska 3, CZ-614 00 (Czech Republic)

    2011-05-15

    By comparing five ecosystem types in the Czech Republic over several years, we recorded the highest carbon sequestration potential in an evergreen Norway spruce forest (100%) and an agroecosystem (65%), followed by European beech forest (25%) and a wetland ecosystem (20%). Because of a massive ecosystem respiration, the final carbon gain of the grassland was negative. Climate was shown to be an important factor of carbon uptake by ecosystems: by varying the growing season length (a 22-d longer season in 2005 than in 2007 increased carbon sink by 13%) or by the effect of short- term synoptic situations (e.g. summer hot and dry days reduced net carbon storage by 58% relative to hot and wet days). Carbon uptake is strongly affected by the ontogeny and a production strategy which is demonstrated by the comparison of seasonal course of carbon uptake between coniferous (Norway spruce) and deciduous (European beech) stands. - Highlights: > Highest carbon sequestration potential in evergreen Norway spruce forest (100%) and an agroecosystem (65%), followed by European beech forest (25%) and a wetland ecosystem (20%). > The final carbon gain of the grassland was negative (massive ecosystem respiration). > Climate is important factor of net primary productivity. > Carbon uptake is strongly affected by the ontogeny and a production strategy of ecosystem. - Identification of the apparent differences in the carbon storage by different ecosystem types.

  6. Role of natural and anthropogenic factors in global and regional climate transformations

    Science.gov (United States)

    Kovalenko, Vladimir A.; Zherebtsov, Gelii A.

    2003-04-01

    Presented is the evidence for the actual manifestation of solar variability in climatic characteristics of the Prebaikalye. This influence on surface air temperature was quantified. A high degree of correlation was established between the mean power of a solar activity cycle and the surface air temperature in the Prebaikalye, averaged over a solar cycle period. It is shown that the main meaningful air temperature variations in the region for the period 1881-1960 were caused by solar activity. The temperature variation amplitude for that period was 1°C. Since the 1960s until the present, with the influence of solar variability persisting, there has been an obvious forcing of another factor whose role was steadily increasing so that as recently as in the last decade it exceeded the contribution from solar variability. For the period 1960-1997, the temperature rise that was not associated with solar variability, was 1.7°C. This new factor is most likely to be the global variations of the thermal regime of the atmosphere that are caused by the anthropogenic factor. This assumption is in agreement with model calculations, pointing to the fact that the most significant manifestation of a global warming should be expected in inland regions of Eurasia. An analysis of the seasonal variations in ground temperature showed that the variations that are taking place to date are most clearly pronounced in the winter-spring period and are associated with a reduction of the stationary period of the Siberian anticyclone. This suggests that the mechanism responsible for the realization of variability factors of regional climate is the global atmospheric circulation rather than a local change of the energy balance of the atmosphere.

  7. The significance of crop co-states for receding horizon optimal control of greenhouse climate

    NARCIS (Netherlands)

    Straten, van G.; Willigenburg, van L.G.; Tap, R.F.

    2002-01-01

    While a tomato crop grows on the time-scale of weeks, the greenhouse climate changes on a time-scale of minutes. The economic optimal control problem of producing good quality crops against minimum input of resources is tackled by a two time-scale decomposition. First, the sub-problem associated to

  8. Vulnerability of Permafrost Soil Carbon to Climate Warming: Evaluating Controls on Microbial Community Composition

    Science.gov (United States)

    Abstract: Despite the fact that permafrost soils contain up to half of the carbon (C) in terrestrial pools, we have a poor understanding of the controls on decomposition in thawed permafrost. Global climate models assume that decomposition increases linearly with temperature, yet decomposition in th...

  9. Electricity versus hydrogen for passenger cars under stringent climate change control

    NARCIS (Netherlands)

    H. Rösler; B. van der Zwaan; I. Keppo; J. Bruggink

    2014-01-01

    In this article we analyze how passenger car transportation in Europe may change this century under permanent high oil prices and stringent climate control policy. We focus on electricity and hydrogen as principal candidate energy carriers, because these two options are increasingly believed to beco

  10. Confirmatory Factor Analysis of the Work Locus of Control Scale

    Science.gov (United States)

    Oliver, Joseph E.; Jose, Paul E.; Brough, Paula

    2006-01-01

    Original formulations of the Work Locus of Control Scale (WLCS) proposed a unidimensional structure of this measure; however, more recently, evidence for a two-dimensional structure has been reported, with separate subscales for internal and external loci of control. The current study evaluates the one- and two-factor models with confirmatory…

  11. Transcription Factor Zbtb20 Controls Regional Specification of Mammalian Archicortex

    DEFF Research Database (Denmark)

    Rosenthal, Eva Helga

    2010-01-01

    Combinatorial expression of sets of transcription factors (TFs) along the mammalian cortex controls its subdivision into functional areas. Unlike neocortex, only few recent data suggest genetic mechanisms controlling the regionalization of the archicortex. TF Emx2 plays a crucial role in patterning...

  12. Climate Control of the Arnamagnæan Archive

    DEFF Research Database (Denmark)

    Padfield, Tim; Ryhl-Svendsen, Morten; Klenz Larsen, Poul;

    2014-01-01

    The small archive of the Arnamagnæan Institute is almost passively air conditioned by being placed between a corridor in a permanently warm Copenhagen university building and the outer wall of the building. It is well insulated towards the warmed building and thinly insulated towards the outside......, so that its temperature is approximately one third of the way between the building interior temperature and the running average outside temperature. The annual average temperature in the archive is above the annual average outside so that the annual average relative humidity (RH) is automatically...... lower than that outside: it is about 50%. The day to day RH remains steady over the entire year because of humidity buffering by the walls and by the hygroscopic content of the archive. Fine control of the RH is provided by pumping in outside air when it is, by chance, of the right water vapour content...

  13. An Integrated Control System for Heating and Indoor Climate Applications

    DEFF Research Database (Denmark)

    Tahersima, Fatemeh

    2012-01-01

    Low temperature hydronic heating and cooling systems connected to renewable energy sources have gained more attention in the recent decades. This is due to the growing public awareness of the adverse environmental impacts of energy generation using fossil fuel. Radiant hydronic sub-floor heating...... pipes and radiator panels are two examples of such systems that have reputation of improving the quality of indoor thermal comfort compared to forced-air heating or cooling units. Specifically, a radiant water-based sub-floor heating system is usually combined with low temperature heat sources, among...... which geothermal heat pump, solar driven heat pumps and the other types are categorized as renewable or renewable energy sources. In the present study, we investigated modeling and control of hydronic heat emitters integrated with a ground-source heat pump. Optimization of the system performance...

  14. Satellite-based assessment of climate controls on US burned area

    Directory of Open Access Journals (Sweden)

    D. C. Morton

    2012-06-01

    Full Text Available Climate regulates fire activity through the buildup and drying of fuels and the conditions for fire ignition and spread. Understanding the dynamics of contemporary climate-fire relationships at national and sub-national scales is critical to assess the likelihood of changes in future fire activity and the potential options for mitigation and adaptation. Here, we conducted the first national assessment of climate controls on US fire activity using two satellite-based estimates of monthly burned area (BA, the Global Fire Emissions Database (GFED, 1997–2010 and Monitoring Trends in Burn Severity (MTBS, 1984–2009 BA products. For each US National Climate Assessment (NCA region, we analyzed the relationships between monthly BA and potential evaporation (PE derived from reanalysis climate data at 0.5° resolution. US fire activity increased over the past 25 yr, with statistically significant increases in MTBS BA for entire US and the Southeast and Southwest NCA regions. Monthly PE was strongly correlated with US fire activity, yet the climate driver of PE varied regionally. Fire season temperature and shortwave radiation were the primary controls on PE} and fire activity in the Alaska, while water deficit (precipitation – PE was strongly correlated with fire activity in the Plains regions and Northwest US. BA and precipitation anomalies were negatively correlated in all regions, although fuel-limited ecosystems in the Southern Plains and Southwest exhibited positive correlations with longer lead times (6–12 months. Fire season PE increased from the 1980s–2000s, enhancing climate-driven fire risk in the southern and western US where PE-BA correlations were strongest. Spatial and temporal patterns of increasing fire season PE and BA during the 1990s–2000s highlight the potential sensitivity of US fire activity to climate change in coming decades. However, climate-fire relationships at the national scale are complex, based on the diversity of

  15. Satellite-based assessment of climate controls on US burned area

    Science.gov (United States)

    Morton, D. C.; Collatz, G. J.; Wang, D.; Randerson, J. T.; Giglio, L.; Chen, Y.

    2013-01-01

    Climate regulates fire activity through the buildup and drying of fuels and the conditions for fire ignition and spread. Understanding the dynamics of contemporary climate-fire relationships at national and sub-national scales is critical to assess the likelihood of changes in future fire activity and the potential options for mitigation and adaptation. Here, we conducted the first national assessment of climate controls on US fire activity using two satellite-based estimates of monthly burned area (BA), the Global Fire Emissions Database (GFED, 1997-2010) and Monitoring Trends in Burn Severity (MTBS, 1984-2009) BA products. For each US National Climate Assessment (NCA) region, we analyzed the relationships between monthly BA and potential evaporation (PE) derived from reanalysis climate data at 0.5° resolution. US fire activity increased over the past 25 yr, with statistically significant increases in MTBS BA for the entire US and the Southeast and Southwest NCA regions. Monthly PE was strongly correlated with US fire activity, yet the climate driver of PE varied regionally. Fire season temperature and shortwave radiation were the primary controls on PE and fire activity in Alaska, while water deficit (precipitation - PE) was strongly correlated with fire activity in the Plains regions and Northwest US. BA and precipitation anomalies were negatively correlated in all regions, although fuel-limited ecosystems in the Southern Plains and Southwest exhibited positive correlations with longer lead times (6-12 months). Fire season PE increased from the 1980's-2000's, enhancing climate-driven fire risk in the southern and western US where PE-BA correlations were strongest. Spatial and temporal patterns of increasing fire season PE and BA during the 1990's-2000's highlight the potential sensitivity of US fire activity to climate change in coming decades. However, climate-fire relationships at the national scale are complex, based on the diversity of fire types

  16. PMP Estimations at Sparsely Controlled Andinian Basins and Climate Change Projections

    Science.gov (United States)

    Lagos Zúñiga, M. A.; Vargas, X.

    2012-12-01

    Probable Maximum Precipitation (PMP) estimation implies an extensive review of hydrometeorological data and understandig of precipitation formation processes. There exists different methodology processes that apply for their estimations and all of them require a good spatial and temporal representation of storms. The estimation of hydrometeorological PMP on sparsely controlled basins is a difficult task, specially if the studied area has an important orographic effect due to mountains and the mixed precipitation occurrence in the most several storms time period, the main task of this study is to propose and estimate PMP in a sparsely controlled basin, affected by abrupt topography and mixed hidrology basin; also analyzing statystic uncertainties estimations and possible climate changes effects in its estimation. In this study the PMP estimation under statistical and hydrometeorological aproaches (watershed-based and traditional depth area duration analysis) was done in a semi arid zone at Puclaro dam in north Chile. Due to the lack of good spatial meteorological representation at the study zone, we propose a methodology to consider the orographic effects of Los Andes due to orographic effects patterns based in a RCM PRECIS-DGF and annual isoyetal maps. Estimations were validated with precipitation patterns for given winters, considering snow route and rainfall gauges at the preferencial wind direction, finding good results. The estimations are also compared with the highest areal storms in USA, Australia, India and China and with frequency analysis in local rain gauge stations in order to decide about the most adequate approach for the study zone. Climate change projections were evaluated with ECHAM5 GCM model, due to its good quality representation in the seasonality and the magnitude of meteorological variables. Temperature projections, for 2040-2065 period, show that there would be a rise in the catchment contributing area that would lead to an increase of the

  17. Chicken barn climate and hazardous volatile compounds control using simple linear regression and PID

    Science.gov (United States)

    Abdullah, A. H.; Bakar, M. A. A.; Shukor, S. A. A.; Saad, F. S. A.; Kamis, M. S.; Mustafa, M. H.; Khalid, N. S.

    2016-07-01

    The hazardous volatile compounds from chicken manure in chicken barn are potentially to be a health threat to the farm animals and workers. Ammonia (NH3) and hydrogen sulphide (H2S) produced in chicken barn are influenced by climate changes. The Electronic Nose (e-nose) is used for the barn's air, temperature and humidity data sampling. Simple Linear Regression is used to identify the correlation between temperature-humidity, humidity-ammonia and ammonia-hydrogen sulphide. MATLAB Simulink software was used for the sample data analysis using PID controller. Results shows that the performance of PID controller using the Ziegler-Nichols technique can improve the system controller to control climate in chicken barn.

  18. Human factors survey of advanced instrumentation and controls

    International Nuclear Information System (INIS)

    A survey oriented towards identifying the human factors issues in regard to the use of advanced instrumentation and controls (I ampersand C) in the nuclear industry was conducted. A number of United States (US) and Canadian nuclear vendors and utilities were participants in the survey. Human factors items, subsumed under the categories of computer-generated displays (CGD), controls, organizational support, training, and related topics, were discussed. The survey found the industry to be concerned about the human factors issues related to the implementation of advanced I ampersand C. Fifteen potential human factors problems were identified. They include: the need for an advanced I ampersand C guideline equivalent to NUREG-0700; a role change in the control room from operator to supervisor; information overload; adequacy of existing training technology for advanced I ampersand C; and operator acceptance and trust. 11 refs., 1 tab

  19. The Factor Replicability of the Litwin and Stringer Organizational Climate Questionnaire: An Inter- and Intra-Organizational Assessment.

    Science.gov (United States)

    Rogers, Evan D.; And Others

    1980-01-01

    Four recent factor analytic studies of the Litwin and Stringer Organizational Climate Questionnaire (LSOCQ) are compared. Although there is somewhat more intra- than inter-organizational replicability of factors, both comparisons raise considerable doubt about the validity of the Litwin and Stringer instrument. (Author)

  20. Fantasy and Reality in the History of Weather and Climate Control

    Science.gov (United States)

    Fleming, J. R.

    2005-12-01

    This presentation examines the history of large-scale weather and climate engineering since 1840, with special reference to imaginative and speculative literature and with special relevance to ethical and policy issues. Ultimate control of the weather and climate embodies both our wildest fantasies and our greatest fears. Fantasy often informs reality (and vice-versa). NASA managers know this well, as do Trekkies. The best science fiction authors typically build from the current state of a field to construct futuristic scenarios that reveal and explore the human condition. Scientists as well often venture into flights of fancy. Though not widely documented, the fantasy-reality axis is also a prominent aspect of the history of the geosciences. James Espy's proposal in the 1840s to enhance precipitation by lighting huge fires, thus stimulating convective updrafts, preceded the widespread charlatanism of the rain-makers, or so-called "pluviculturalists," in the western U.S. One hundred years later, promising discoveries in "cloud seeding" by Irving Langmuir and his associates at the General Electric Corporation rapidly devolved into unsupportable proposals and questionable practices by military and commercial rain-makers seeking to control the weather. During the Cold War, Soviet engineers also promoted a chilling vision (to Westerners) of global climate control. Recently, rather immodest proposals to "fix" a climate system perceived to be out of control have received wide circulation. In 2003 the U.S. Pentagon released a report recommending that the government should "explore geo-engineering options that control the climate." In 2004 a symposium in Cambridge, England set out to "identify, debate, and evaluate" possible, but highly controversial options for the design and construction of engineering projects for the management and mitigation of global climate change. This talk will locate the history of weather and climate modification within a long tradition of

  1. Employees' perspective on organizational climate and job motivation factors and their relationship with the Blood Transfusion Organization's employees, 2012

    OpenAIRE

    Iraj Soltani; Mostafa Aghahosseini; Nahid Akbari

    2014-01-01

    This study aimed to examine the employees' views about the organizational climate dimensions and motivational factors and explain their relationship in the Blood Transfusion Organization's employees. Eighty-seven subjects as the population were selected from all parts of the organization. The research tools included the questionnaires of organizational climate, motivational potential dimensions (job identification), and the needs. According to goals and questions, the data from the research q...

  2. A longitudinal study of mental health symptoms in young prisoners: exploring the influence of personal factors and the correctional climate

    OpenAIRE

    Gonçalves, Leonel C.; Endrass, Jérôme; Rossegger, Astrid; Dirkzwager, Anja J. E.

    2016-01-01

    Background Despite the high prevalence rate of mental health problems among young prisoners, little is known about the longitudinal course and covariates of their mental health symptoms during incarceration, especially the influence of the correctional climate. The current study aimed: (1) to examine changes in young prisoners’ mental health symptoms during incarceration, (2) to identify personal factors associated with their mental health symptoms and perceptions of the correctional climate,...

  3. A longitudinal study of mental health symptoms in young prisoners : exploring the influence of personal factors and the correctional climate

    OpenAIRE

    Gonçalves, Leonel C.; Endrass, Jérôme; Rossegger, Astrid; Dirkzwager, Anja J. E.

    2016-01-01

    BackgroundDespite the high prevalence rate of mental health problems among young prisoners, little is known about the longitudinal course and covariates of their mental health symptoms during incarceration, especially the influence of the correctional climate. The current study aimed: (1) to examine changes in young prisoners’ mental health symptoms during incarceration, (2) to identify personal factors associated with their mental health symptoms and perceptions of the correctional climate, ...

  4. Comparison of thermal comfort performance of two different types of road vehicle climate control systems.

    Science.gov (United States)

    Quanten, S; Van Brecht, A; Berckmans, D

    2007-03-01

    The performance of climate control systems in vehicles becomes more and more important, especially against the background of the important relationship between compartment climate and driver mental condition and, thus, traffic safety. The performance of two different types of climate control systems, an un-air-conditioned heating/cooling device (VW) and an air-conditioning climate control unit (BMW), is compared using modern and practical evaluation techniques quantifying both the dynamic 3-D temperature distribution and the local air refreshment rate. Both systems suffer from considerable temperature gradients: temperature gradients in the U-AC (VW) car up to 8-9 degrees C are encountered, while the AC (BMW) delivers clear improvement resulting in temperature gradients of 5-6 degrees C. The experiments clearly demonstrate the effect of the presence of even a single passenger on the thermal regime, increasing the existing thermal discrepancies in the compartment with 15% independent of ventilation rate. Furthermore, in terms of air refreshment rates in the vehicle compartment, an air-conditioning unit halves the air refreshment time at all positions in the vehicle cabin, delivering a significant improvement in terms of human comfort. Similarly, extra air inlets in the back compartment of a car deliver progress in terms of cabin refreshment rate (93 s down to 50 s).

  5. Atmospheric carbon dioxide and the long-term control of the Earth's climate

    Directory of Open Access Journals (Sweden)

    J. H. Carver

    Full Text Available A CO2-weathering model has been used to explore the possible evolution of the Earth's climate as the Sun steadily brightened throughout geologic time. The results of the model calculations can be described in terms of three, qualitatively different, "Megaclimates". Mega-climate 1 resulted from a period of rapid outgassing in the early Archean, with high, but declining, temperatures caused by the small weathering rates on a largely water-covered planet. Mega-climate 2 began about 3 Gyear ago as major continental land masses developed, increasing the weathering rate in the early Proterozoic and thereby depleting the atmospheric CO2 concentration. This process produced the first Precambrian glaciations about 2.3 Gyear ago. During Mega-climate 2, evolutionary biological processes increased the surface weatherability in incremental steps and plate tectonics modulated the CO2 outgassing rate with an estimated period of 150 Myear (approximately one-half the period for the formation and breakup of super continents. Throughout Mega-climate 2 the surface temperature was controlled by variations in the atmospheric CO2 level allowing transitions between glacial and non-glacial conditions. The results of the model for Mega-climate 2 are in agreement with the occurrence (and absence of glaciations in the geologic record. Extending the model to the future suggests that CO2 control of the Earth's temperature will no longer be able to compensate for a solar flux that continues to increase. The present level of atmospheric CO2 is so small that further reduction in CO2 cannot prevent the Earth from experiencing Mega-climate 3 with steadily increasing surface temperatures caused by the continued brightening of the Sun. During Mega-climate 3, the main danger to the biosphere would come not from an increasing temperature but from a decreasing (rather than an increasing CO2

  6. Satellite-based assessment of climate controls on US burned area

    Directory of Open Access Journals (Sweden)

    D. C. Morton

    2013-01-01

    Full Text Available Climate regulates fire activity through the buildup and drying of fuels and the conditions for fire ignition and spread. Understanding the dynamics of contemporary climate–fire relationships at national and sub-national scales is critical to assess the likelihood of changes in future fire activity and the potential options for mitigation and adaptation. Here, we conducted the first national assessment of climate controls on US fire activity using two satellite-based estimates of monthly burned area (BA, the Global Fire Emissions Database (GFED, 1997–2010 and Monitoring Trends in Burn Severity (MTBS, 1984–2009 BA products. For each US National Climate Assessment (NCA region, we analyzed the relationships between monthly BA and potential evaporation (PE derived from reanalysis climate data at 0.5° resolution. US fire activity increased over the past 25 yr, with statistically significant increases in MTBS BA for the entire US and the Southeast and Southwest NCA regions. Monthly PE was strongly correlated with US fire activity, yet the climate driver of PE varied regionally. Fire season temperature and shortwave radiation were the primary controls on PE and fire activity in Alaska, while water deficit (precipitation – PE was strongly correlated with fire activity in the Plains regions and Northwest US. BA and precipitation anomalies were negatively correlated in all regions, although fuel-limited ecosystems in the Southern Plains and Southwest exhibited positive correlations with longer lead times (6–12 months. Fire season PE increased from the 1980's–2000's, enhancing climate-driven fire risk in the southern and western US where PE–BA correlations were strongest. Spatial and temporal patterns of increasing fire season PE and BA during the 1990's–2000's highlight the potential sensitivity of US fire activity to climate change in coming decades. However, climate-fire relationships at the national scale are complex, based on the

  7. Climate, orography and scale controls on flood frequency in Triveneto (Italy)

    Science.gov (United States)

    Persiano, Simone; Castellarin, Attilio; Salinas, Jose Luis; Domeneghetti, Alessio; Brath, Armando

    2016-05-01

    The growing concern about the possible effects of climate change on flood frequency regime is leading Authorities to review previously proposed reference procedures for design-flood estimation, such as national flood frequency models. Our study focuses on Triveneto, a broad geographical region in North-eastern Italy. A reference procedure for design flood estimation in Triveneto is available from the Italian NCR research project "VA.PI.", which considered Triveneto as a single homogeneous region and developed a regional model using annual maximum series (AMS) of peak discharges that were collected up to the 1980s by the former Italian Hydrometeorological Service. We consider a very detailed AMS database that we recently compiled for 76 catchments located in Triveneto. All 76 study catchments are characterized in terms of several geomorphologic and climatic descriptors. The objective of our study is threefold: (1) to inspect climatic and scale controls on flood frequency regime; (2) to verify the possible presence of changes in flood frequency regime by looking at changes in time of regional L-moments of annual maximum floods; (3) to develop an updated reference procedure for design flood estimation in Triveneto by using a focused-pooling approach (i.e. Region of Influence, RoI). Our study leads to the following conclusions: (1) climatic and scale controls on flood frequency regime in Triveneto are similar to the controls that were recently found in Europe; (2) a single year characterized by extreme floods can have a remarkable influence on regional flood frequency models and analyses for detecting possible changes in flood frequency regime; (3) no significant change was detected in the flood frequency regime, yet an update of the existing reference procedure for design flood estimation is highly recommended and we propose the RoI approach for properly representing climate and scale controls on flood frequency in Triveneto, which cannot be regarded as a single

  8. Controlling harmful cyanobacterial blooms in a world experiencing anthropogenic and climatic-induced change

    International Nuclear Information System (INIS)

    Harmful (toxic, food web altering, hypoxia generating) cyanobacterial algal blooms (CyanoHABs) are proliferating world-wide due to anthropogenic nutrient enrichment, and they represent a serious threat to the use and sustainability of our freshwater resources. Traditionally, phosphorus (P) input reductions have been prescribed to control CyanoHABs, because P limitation is widespread and some CyanoHABs can fix atmospheric nitrogen (N2) to satisfy their nitrogen (N) requirements. However, eutrophying systems are increasingly plagued with non N2 fixing CyanoHABs that are N and P co-limited or even N limited. In many of these systems N loads are increasing faster than P loads. Therefore N and P input constraints are likely needed for long-term CyanoHAB control in such systems. Climatic changes, specifically warming, increased vertical stratification, salinization, and intensification of storms and droughts play additional, interactive roles in modulating CyanoHAB frequency, intensity, geographic distribution and duration. In addition to having to consider reductions in N and P inputs, water quality managers are in dire need of effective tools to break the synergy between nutrient loading and hydrologic regimes made more favorable for CyanoHABs by climate change. The more promising of these tools make affected waters less hospitable for CyanoHABs by 1) altering the hydrology to enhance vertical mixing and/or flushing and 2) decreasing nutrient fluxes from organic rich sediments by physically removing the sediments or capping sediments with clay. Effective future CyanoHAB management approaches must incorporate both N and P loading dynamics within the context of altered thermal and hydrologic regimes associated with climate change. - Research Highlights: → Toxic cyanobacterial blooms (CyanoHABs) increasingly threaten global water supplies. → Human (nutrient) and climate (hydrology, temperature) changes synergistically promote CyanoHABs. → CyanoHAB control involves

  9. Controlling harmful cyanobacterial blooms in a world experiencing anthropogenic and climatic-induced change

    Energy Technology Data Exchange (ETDEWEB)

    Paerl, Hans W., E-mail: hpaerl@email.unc.edu; Hall, Nathan S.; Calandrino, Elizabeth S.

    2011-04-15

    Harmful (toxic, food web altering, hypoxia generating) cyanobacterial algal blooms (CyanoHABs) are proliferating world-wide due to anthropogenic nutrient enrichment, and they represent a serious threat to the use and sustainability of our freshwater resources. Traditionally, phosphorus (P) input reductions have been prescribed to control CyanoHABs, because P limitation is widespread and some CyanoHABs can fix atmospheric nitrogen (N{sub 2}) to satisfy their nitrogen (N) requirements. However, eutrophying systems are increasingly plagued with non N{sub 2} fixing CyanoHABs that are N and P co-limited or even N limited. In many of these systems N loads are increasing faster than P loads. Therefore N and P input constraints are likely needed for long-term CyanoHAB control in such systems. Climatic changes, specifically warming, increased vertical stratification, salinization, and intensification of storms and droughts play additional, interactive roles in modulating CyanoHAB frequency, intensity, geographic distribution and duration. In addition to having to consider reductions in N and P inputs, water quality managers are in dire need of effective tools to break the synergy between nutrient loading and hydrologic regimes made more favorable for CyanoHABs by climate change. The more promising of these tools make affected waters less hospitable for CyanoHABs by 1) altering the hydrology to enhance vertical mixing and/or flushing and 2) decreasing nutrient fluxes from organic rich sediments by physically removing the sediments or capping sediments with clay. Effective future CyanoHAB management approaches must incorporate both N and P loading dynamics within the context of altered thermal and hydrologic regimes associated with climate change. - Research Highlights: {yields} Toxic cyanobacterial blooms (CyanoHABs) increasingly threaten global water supplies. {yields} Human (nutrient) and climate (hydrology, temperature) changes synergistically promote CyanoHABs. {yields

  10. Environmental optimal control strategies based on plant canopy photosynthesis responses and greenhouse climate model

    Science.gov (United States)

    Deng, Lujuan; Xie, Songhe; Cui, Jiantao; Liu, Tao

    2006-11-01

    It is the essential goal of intelligent greenhouse environment optimal control to enhance income of cropper and energy save. There were some characteristics such as uncertainty, imprecision, nonlinear, strong coupling, bigger inertia and different time scale in greenhouse environment control system. So greenhouse environment optimal control was not easy and especially model-based optimal control method was more difficult. So the optimal control problem of plant environment in intelligent greenhouse was researched. Hierarchical greenhouse environment control system was constructed. In the first level data measuring was carried out and executive machine was controlled. Optimal setting points of climate controlled variable in greenhouse was calculated and chosen in the second level. Market analysis and planning were completed in third level. The problem of the optimal setting point was discussed in this paper. Firstly the model of plant canopy photosynthesis responses and the model of greenhouse climate model were constructed. Afterwards according to experience of the planting expert, in daytime the optimal goals were decided according to the most maximal photosynthesis rate principle. In nighttime on plant better growth conditions the optimal goals were decided by energy saving principle. Whereafter environment optimal control setting points were computed by GA. Compared the optimal result and recording data in real system, the method is reasonable and can achieve energy saving and the maximal photosynthesis rate in intelligent greenhouse

  11. Climaite - a three factor climate change ecosystem manipulation study: set up and approaches for data analysis

    DEFF Research Database (Denmark)

    N. Mikkelsen, Teis; Beier, Claus; Schmidt, Inger Kappel;

    In a new Danish climate change related field scale experiment, CLIMAITE, we are investigating the impacts of individual and multiple simultaneous global changes on ecosystem processes and functioning in a Danish semi natural grassland vegetation dominated by Deschampsia flexuosa and Calluna...... vulgaris. The Climaite experiment involves three global change factors: elevated CO2 (510 ppm), elevated temperature (+ 1-2 C) and altered precipitation (1-1.5 months extended drought in May-July) all compared to ambient conditions in a complete factorial design. The experiment includes six replicates......, the physiological status of plants, soil water chemistry and emission of green house gasses. The CO2 is enhanced all year around during daylight hours in 6 plots by the use of a FACE system (F. Miglietta design). Temperature elevation is achieved by night time warming where IR reflective curtains automatically...

  12. Leaf litter nitrogen concentration as related to climatic factors in Eurasian forests

    DEFF Research Database (Denmark)

    Liu, Chunjiang; Berg, Bjørn; Kutsch, Werner;

    2006-01-01

    The aim of this study is to determine the patterns of nitrogen (N) concentrations in leaf litter of forest trees as functions of climatic factors, annual average temperature (Temp, °C) and annual precipitation (Precip, dm) and of forest type (coniferous vs. broadleaf, deciduous vs. evergreen, Pinus......, etc.). Location: The review was conducted using data from studies across the Eurasian continent. Methods: Leaf litter N concentration was compiled from 204 sets of published data (81 sets from coniferous and 123 from broadleaf forests in Eurasia). We explored the relationships between leaf litter N...... concentration and Temp and Precip by means of regression analysis. Leaf litter data from N2-fixing species were excluded from the analysis. Results: Over the Eurasian continent, leaf litter N concentration increased with increasing Temp and Precip within functional groups such as conifers, broadleaf, deciduous...

  13. Agricultural Policy, Climate Factors and Grain Output:Evidence From Household Survey Data in Rural China

    Institute of Scientific and Technical Information of China (English)

    CHEN Yong-fu; WU Zhi-gang; ZHU Tie-hui; YANG Lei; MA Guo-ying; Chien Hsiao-ping

    2013-01-01

    This paper estimates a stochastic frontier function using a panel data set that includes 4 961 farmer households for the period of 2005-2009 to decompose the growth of grain production and the total factor productivity (TFP) growth at the farmer level. The empirical results show that the major contributor to the grain output growth for farmers is input growth and that its average contribution accounts for 60.92%of farmer’s grain production growth in the period of 2006-2009, whereas the average contributions sourced from TFP growth and residuals are only 17.30 and 21.78%, respectively. The growth of intermediate inputs is a top contributor with an average contribution of 44.46%, followed by the planted area (18.16%), investment in fixed assets (1.05%), and labor input (-2.75%), indicating that the contribution from the farmer’s input growth is mainly due to the growth of intermediate inputs and that the decline in labor inputs has become an obstacle for farmers in seeking grain output growth. Among the elements consisting of TFP growth, the contribution of technical progress is the largest (32.04%), followed by grain subsidies (8.55%), the average monthly temperature (4.26%), the average monthly precipitation (-0.88%), the adjusted scale effect (-5.66%), and growth in technical efficiency (-21.01%). In general, the contribution of climate factors and agricultural policy factor are positive and significant.

  14. How Do Various Maize Crop Models Vary in Their Responses to Climate Change Factors?

    Science.gov (United States)

    Bassu, Simona; Brisson, Nadine; Grassini, Patricio; Durand, Jean-Louis; Boote, Kenneth; Lizaso, Jon; Jones, James W.; Rosenzweig, Cynthia; Ruane, Alex C.; Adam, Myriam; Baron, Christian; Basso, Bruno; Biernath, Christian; Boogaard, Hendrik; Conijn, Sjaak; Corbeels, Marc; Deryng, Delphine; DeSanctis, Giacomo; Gayler, Sebastian; Grassini, Patricio; Hatfield, Jerry; Hoek, Steven; Izaurralde, Cesar; Jongschaap, Raymond; Kemanian, Armen R.; Kersebaum, K. Christian

    2014-01-01

    Potential consequences of climate change on crop production can be studied using mechanistic crop simulation models. While a broad variety of maize simulation models exist, it is not known whether different models diverge on grain yield responses to changes in climatic factors, or whether they agree in their general trends related to phenology, growth, and yield. With the goal of analyzing the sensitivity of simulated yields to changes in temperature and atmospheric carbon dioxide concentrations [CO2], we present the largest maize crop model intercomparison to date, including 23 different models. These models were evaluated for four locations representing a wide range of maize production conditions in the world: Lusignan (France), Ames (USA), Rio Verde (Brazil) and Morogoro (Tanzania). While individual models differed considerably in absolute yield simulation at the four sites, an ensemble of a minimum number of models was able to simulate absolute yields accurately at the four sites even with low data for calibration, thus suggesting that using an ensemble of models has merit. Temperature increase had strong negative influence on modeled yield response of roughly -0.5 Mg ha(sup 1) per degC. Doubling [CO2] from 360 to 720 lmol mol 1 increased grain yield by 7.5% on average across models and the sites. That would therefore make temperature the main factor altering maize yields at the end of this century. Furthermore, there was a large uncertainty in the yield response to [CO2] among models. Model responses to temperature and [CO2] did not differ whether models were simulated with low calibration information or, simulated with high level of calibration information.

  15. Seasonal Shift in Climatic Limiting Factors on Tree Transpiration: Evidence from Sap Flow Observations at Alpine Treelines in Southeast Tibet

    Science.gov (United States)

    Liu, Xinsheng; Nie, Yuqin; Luo, Tianxiang; Yu, Jiehui; Shen, Wei; Zhang, Lin

    2016-01-01

    Alpine and northern treelines are primarily controlled by low temperatures. However, little is known about the impact of low soil temperature on tree transpiration at treelines. We aim to test the hypothesis that in cold-limited forests, the main limiting factors for tree transpiration switch from low soil temperature before summer solstice to atmospheric evaporative demand after summer solstice, which generally results in low transpiration in the early growing season. Sap flow, meteorological factors and predawn needle water potential were continuously monitored throughout one growing season across Smith fir (Abies georgei var. smithii) and juniper (Juniperus saltuaria) treelines in southeast Tibet. Sap flow started in early May and corresponded to a threshold mean air-temperature of 0°C. Across tree species, transpiration was mainly limited by low soil temperature prior to the summer solstice but by vapor pressure deficit and solar radiation post-summer solstice, which was further confirmed on a daily scale. As a result, tree transpiration for both tree species was significantly reduced in the pre-summer solstice period as compared to post-summer solstice, resulting in a lower predawn needle water potential for Smith fir trees in the early growing season. Our data supported the hypothesis, suggesting that tree transpiration mainly responds to soil temperature variations in the early growing season. The results are important for understanding the hydrological response of cold-limited forest ecosystems to climate change.

  16. Seasonal Shift in Climatic Limiting Factors on Tree Transpiration: Evidence from Sap Flow Observations at Alpine Treelines in Southeast Tibet.

    Science.gov (United States)

    Liu, Xinsheng; Nie, Yuqin; Luo, Tianxiang; Yu, Jiehui; Shen, Wei; Zhang, Lin

    2016-01-01

    Alpine and northern treelines are primarily controlled by low temperatures. However, little is known about the impact of low soil temperature on tree transpiration at treelines. We aim to test the hypothesis that in cold-limited forests, the main limiting factors for tree transpiration switch from low soil temperature before summer solstice to atmospheric evaporative demand after summer solstice, which generally results in low transpiration in the early growing season. Sap flow, meteorological factors and predawn needle water potential were continuously monitored throughout one growing season across Smith fir (Abies georgei var. smithii) and juniper (Juniperus saltuaria) treelines in southeast Tibet. Sap flow started in early May and corresponded to a threshold mean air-temperature of 0°C. Across tree species, transpiration was mainly limited by low soil temperature prior to the summer solstice but by vapor pressure deficit and solar radiation post-summer solstice, which was further confirmed on a daily scale. As a result, tree transpiration for both tree species was significantly reduced in the pre-summer solstice period as compared to post-summer solstice, resulting in a lower predawn needle water potential for Smith fir trees in the early growing season. Our data supported the hypothesis, suggesting that tree transpiration mainly responds to soil temperature variations in the early growing season. The results are important for understanding the hydrological response of cold-limited forest ecosystems to climate change.

  17. Seasonal shift in climatic limiting factors on tree transpiration: evidence from sap flow observations at alpine treelines in southeast Tibet

    Directory of Open Access Journals (Sweden)

    Liu Xinsheng

    2016-07-01

    Full Text Available Alpine and northern treelines are primarily controlled by low temperatures. However, little is known about the impact of low soil temperature on tree transpiration at treelines. We aim to test the hypothesis that in cold-limited forests, the main limiting factors for tree transpiration switch from low soil temperature before summer solstice to atmospheric evaporative demand after summer solstice, which generally results in low transpiration in the early growing season. Sap flow, meteorological factors and predawn needle water potential were continuously monitored throughout one growing season across Smith fir (Abies georgei var. smithii and juniper (Juniperus saltuaria treelines in southeast Tibet. Sap flow started in early May and corresponded to a threshold mean air-temperature of 0 oC. Across tree species, transpiration was mainly limited by low soil temperature prior to the summer solstice but by vapor pressure deficit and solar radiation post-summer solstice, which was further confirmed on a daily scale. As a result, tree transpiration for both tree species was significantly reduced in the pre-summer solstice period as compared to post-summer solstice, resulting in a lower predawn needle water potential for Smith fir trees in the early growing season. Our data supported the hypothesis, suggesting that tree transpiration mainly responds to soil temperature variations in the early growing season. The results are important for understanding the hydrological response of cold-limited forest ecosystems to climate change.

  18. Risk factors for ovarian cancer: a case-control study.

    OpenAIRE

    Booth, M.; Beral, V; SMITH, P.

    1989-01-01

    A hospital-based case-control study of ovarian cancer was conducted in London and Oxford between October 1978 and February 1983. Menstrual characteristics, reproductive and contraceptive history and history of exposure to various environmental factors were compared between 235 women with histologically diagnosed epithelial ovarian cancer and 451 controls. High gravidity, hysterectomy, female sterilisation and oral contraceptive use were associated with a reduced risk of ovarian cancer. Infert...

  19. Teleoperator hand controllers: A contextual human factors assessment

    Energy Technology Data Exchange (ETDEWEB)

    Draper, J.V.

    1994-05-01

    This document provides a human factors assessment of controllers for use with remotely controlled manipulators deployed to remove hazardous waste from underground storage tanks. The analysis concentrates on controller technique (i.e., the broad class of hand controller) and not on details of controller ergonomics. Examples of controller techniques include, for example, direct rate control, resolved unilateral position control, and direct bilateral position control. Using an existing concept, the Tank Waste Retrieval Manipulator System, as a reference, two basic types of manipulators may be identified for this application. A long reach, gross-positioning manipulator (LRM) may be used to position a smaller manipulator or an end-effector within a work site. For a Long Reach Manipulator, which will have an enormous motion range and be capable of high end-effector velocity, it will be safest and most efficient to use a resolved rate control system. A smaller, dexterous manipulator may be used to perform handling work within a relatively small work site, (i.e., to complete tasks requiring near-human dexterity). For a Dexterous Manipulator, which will have a smaller motion range than the LRM and be required to perform more difficult tasks, a resolved bilateral position control system will be safest and most efficient. However, during some waste recovery tasks it may be important to support the users by restricting movements to a single plane or axis. This can be done with a resolved bilateral position control system by (1) using the master controller force output to restrict controller inputs or (2) switching the controller to a multiaxis rate control mode and using the force output to provide a spring return to center functionality.

  20. Potential risk factors for diabetic neuropathy: a case control study

    Directory of Open Access Journals (Sweden)

    Nooraei Mahdi

    2005-12-01

    Full Text Available Abstract Background Diabetes mellitus type II afflicts at least 2 million people in Iran. Neuropathy is one of the most common complications of diabetes and lowers the patient's quality of life. Since neuropathy often leads to ulceration and amputation, we have tried to elucidate the factors that can affect its progression. Methods In this case-control study, 110 diabetic patients were selected from the Shariati Hospital diabetes clinic. Michigan Neuropathic Diabetic Scoring (MNDS was used to differentiate cases from controls. The diagnosis of neuropathy was confirmed by nerve conduction studies (nerve conduction velocity and electromyography. The multiple factors compared between the two groups included consumption of angiotensin converting enzyme inhibitors (ACEI, blood pressure, serum lipid level, sex, smoking, method of diabetes control and its quality. Results Statistically significant relationships were found between neuropathy and age, gender, quality of diabetes control and duration of disease (P values in the order: 0.04, 0.04, Conclusion In this study, hyperglycemia was the only modifiable risk factor for diabetic neuropathy. Glycemic control reduces the incidence of neuropathy, slows its progression and improves the diabetic patient's quality of life. More attention must be paid to elderly male diabetic patients with poor diabetes control with regard to regular foot examinations and more practical education.

  1. Exploring factors influencing farmers' willingness to pay (WTP) for a planned adaptation programme to address climatic issues in agricultural sectors.

    Science.gov (United States)

    Ahmed, Adeel; Masud, Muhammad Mehedi; Al-Amin, Abul Quasem; Yahaya, Siti Rohani Binti; Rahman, Mahfuzur; Akhtar, Rulia

    2015-06-01

    This study empirically estimates farmers' willingness to pay (WTP) for a planned adaptation programme for addressing climate issues in Pakistan's agricultural sectors. The contingent valuation method (CVM) was employed to determine a monetary valuation of farmers' preferences for a planned adaptation programme by ascertaining the value attached to address climatic issues. The survey was conducted by distributing structured questionnaires among Pakistani farmers. The study found that 67 % of respondents were willing to pay for a planned adaptation programme. However, several socioeconomic and motivational factors exert greater influence on their willingness to pay (WTP). This paper specifies the steps needed for all institutional bodies to better address issues in climate change. The outcomes of this paper will support attempts by policy makers to design an efficient adaptation framework for mitigating and adapting to the adverse impacts of climate change. PMID:25613801

  2. Exploring factors influencing farmers' willingness to pay (WTP) for a planned adaptation programme to address climatic issues in agricultural sectors.

    Science.gov (United States)

    Ahmed, Adeel; Masud, Muhammad Mehedi; Al-Amin, Abul Quasem; Yahaya, Siti Rohani Binti; Rahman, Mahfuzur; Akhtar, Rulia

    2015-06-01

    This study empirically estimates farmers' willingness to pay (WTP) for a planned adaptation programme for addressing climate issues in Pakistan's agricultural sectors. The contingent valuation method (CVM) was employed to determine a monetary valuation of farmers' preferences for a planned adaptation programme by ascertaining the value attached to address climatic issues. The survey was conducted by distributing structured questionnaires among Pakistani farmers. The study found that 67 % of respondents were willing to pay for a planned adaptation programme. However, several socioeconomic and motivational factors exert greater influence on their willingness to pay (WTP). This paper specifies the steps needed for all institutional bodies to better address issues in climate change. The outcomes of this paper will support attempts by policy makers to design an efficient adaptation framework for mitigating and adapting to the adverse impacts of climate change.

  3. Climatic controls on ecosystem resilience: Postfire regeneration in the Cape Floristic Region of South Africa

    Science.gov (United States)

    Wilson, Adam M.; Latimer, Andrew M.; Silander, John A.

    2015-01-01

    Conservation of biodiversity and natural resources in a changing climate requires understanding what controls ecosystem resilience to disturbance. This understanding is especially important in the fire-prone Mediterranean systems of the world. The fire frequency in these systems is sensitive to climate, and recent climate change has resulted in more frequent fires over the last few decades. However, the sensitivity of postfire recovery and biomass/fuel load accumulation to climate is less well understood than fire frequency despite its importance in driving the fire regime. In this study, we develop a hierarchical statistical framework to model postfire ecosystem recovery using satellite-derived observations of vegetation as a function of stand age, topography, and climate. In the Cape Floristic Region (CFR) of South Africa, a fire-prone biodiversity hotspot, we found strong postfire recovery gradients associated with climate resulting in faster recovery in regions with higher soil fertility, minimum July (winter) temperature, and mean January (summer) precipitation. Projections using an ensemble of 11 downscaled Coupled Model Intercomparison Project Phase 5 (CMIP5) general circulation models (GCMs) suggest that warmer winter temperatures in 2080–2100 will encourage faster postfire recovery across the region, which could further increase fire frequency due to faster fuel accumulation. However, some models project decreasing precipitation in the western CFR, which would slow recovery rates there, likely reducing fire frequency through lack of fuel and potentially driving local biome shifts from fynbos shrubland to nonburning semidesert vegetation. This simple yet powerful approach to making inferences from large, remotely sensed datasets has potential for wide application to modeling ecosystem resilience in disturbance-prone ecosystems globally. PMID:26150521

  4. What roles do team climate, roster control, and work life conflict play in shiftworkers' fatigue longitudinally?

    Science.gov (United States)

    Pisarski, Anne; Barbour, Jennifer P

    2014-05-01

    The study aimed to examine shiftworkers fatigue and the longitudinal relationships that impact on fatigue such as team climate, work life conflict, control of shifts and shift type in shift working nurses. We used a quantitative survey methodology and analysed data with a moderated hierarchical multiple regression. After matching across two time periods 18 months apart, the sample consisted of 166 nurses from one Australian hospital. Of these nurses, 61 worked two rotating day shifts (morning & afternoon/evening) and 105 were rotating shiftworkers who worked three shifts (morning afternoon/evening and nights). The findings suggest that control over shift scheduling can have significant effects on fatigue for both two-shift and three-shift workers. A significant negative relationship between positive team climate and fatigue was moderated by shift type. At both Time 1 and Time 2, work life conflict was the strongest predictor of concurrent fatigue, but over time it was not.

  5. Northern Hemisphere Controls on Tropical Southeast African Climate During the Past 60,000 Years

    Science.gov (United States)

    Tierney, Jessica E.; Russell, James M.; Huang, Yongsong; Damsté, Jaap S. Sinninghe; Hopmans, Ellen C.; Cohen, Andrew S.

    2008-10-01

    The processes that control climate in the tropics are poorly understood. We applied compound-specific hydrogen isotopes (δD) and the TEX86 (tetraether index of 86 carbon atoms) temperature proxy to sediment cores from Lake Tanganyika to independently reconstruct precipitation and temperature variations during the past 60,000 years. Tanganyika temperatures follow Northern Hemisphere insolation and indicate that warming in tropical southeast Africa during the last glacial termination began to increase ~3000 years before atmospheric carbon dioxide concentrations. δD data show that this region experienced abrupt changes in hydrology coeval with orbital and millennial-scale events recorded in Northern Hemisphere monsoonal climate records. This implies that precipitation in tropical southeast Africa is more strongly controlled by changes in Indian Ocean sea surface temperatures and the winter Indian monsoon than by migration of the Intertropical Convergence Zone.

  6. Farmers' Perceptions of Climate Variability and Factors Influencing Adaptation: Evidence from Anhui and Jiangsu, China

    Science.gov (United States)

    Kibue, Grace Wanjiru; Liu, Xiaoyu; Zheng, Jufeng; zhang, Xuhui; Pan, Genxing; Li, Lianqing; Han, Xiaojun

    2016-05-01

    Impacts of climate variability and climate change are on the rise in China posing great threat to agriculture and rural livelihoods. Consequently, China is undertaking research to find solutions of confronting climate change and variability. However, most studies of climate change and variability in China largely fail to address farmers' perceptions of climate variability and adaptation. Yet, without an understanding of farmers' perceptions, strategies are unlikely to be effective. We conducted questionnaire surveys of farmers in two farming regions, Yifeng, Jiangsu and Qinxi, Anhui achieving 280 and 293 responses, respectively. Additionally, we used climatological data to corroborate the farmers' perceptions of climate variability. We found that farmers' were aware of climate variability such that were consistent with climate records. However, perceived impacts of climate variability differed between the two regions and were influenced by farmers' characteristics. In addition, the vast majorities of farmers were yet to make adjustments in their farming practices as a result of numerous challenges. These challenges included socioeconomic and socio-cultural barriers. Results of logit modeling showed that farmers are more likely to adapt to climate variability if contact with extension services, frequency of seeking information, household heads' education, and climate variability perceptions are improved. These results suggest the need for policy makers to understand farmers' perceptions of climate variability and change in order to formulate policies that foster adaptation, and ultimately protect China's agricultural assets.

  7. Large-scale climatic and geophysical controls on the leaf economics spectrum.

    Science.gov (United States)

    Asner, Gregory P; Knapp, David E; Anderson, Christopher B; Martin, Roberta E; Vaughn, Nicholas

    2016-07-12

    Leaf economics spectrum (LES) theory suggests a universal trade-off between resource acquisition and storage strategies in plants, expressed in relationships between foliar nitrogen (N) and phosphorus (P), leaf mass per area (LMA), and photosynthesis. However, how environmental conditions mediate LES trait interrelationships, particularly at large biospheric scales, remains unknown because of a lack of spatially explicit data, which ultimately limits our understanding of ecosystem processes, such as primary productivity and biogeochemical cycles. We used airborne imaging spectroscopy and geospatial modeling to generate, to our knowledge, the first biospheric maps of LES traits, here centered on 76 million ha of Andean and Amazonian forest, to assess climatic and geophysical determinants of LES traits and their interrelationships. Elevation and substrate were codominant drivers of leaf trait distributions. Multiple additional climatic and geophysical factors were secondary determinants of plant traits. Anticorrelations between N and LMA followed general LES theory, but topo-edaphic conditions strongly mediated and, at times, eliminated this classic relationship. We found no evidence for simple P-LMA or N-P trade-offs in forest canopies; rather, we mapped a continuum of N-P-LMA interactions that are sensitive to elevation and temperature. Our results reveal nested climatic and geophysical filtering of LES traits and their interrelationships, with important implications for predictions of forest productivity and acclimation to rapid climate change. PMID:27354534

  8. Impact of climatic factors to the percentage of young in the population of brown hare (Lepus europaeus P in the Bačka district

    Directory of Open Access Journals (Sweden)

    Beuković Miloš

    2013-01-01

    Full Text Available Climatic factors, especially temperature and precipitations, greatly affect the dynamics of the hare number and population. Climatic factors directly affect the physiological and reproductive processes of both individuals and entire populations, or indirectly, through the availability of food, competition with other species, predators and other. The age structure of the hare population at the end of the period of reproduction is an important indicator of the population growth that is used for planning the level of explotation of the hare population (hunting. The rational use of the hare's population is one of the most important protection procedures and it should be well monitored and controlled by the hunting professionals. We used the average monthly temperature and the sum of monthly precipitations in the hare reproductive period (March-September during ten years (2000 - 2009, together with the percent of young in the hare population, on the territory of Bačka, for multiple regression (stepwise analysis. Results of the regression analysis show an association between the percentage of young hares and the influence of climatic factors. The average temperature and sum of precipitation in June, are the strongest predictor of the percent of young in the hare’s population in Bačka. According to the coefficient of determination (R2=0.50 climatic parameters account for 50% of variance in the percentage of young hares in Bačka. The regression correlation coefficient of all factors was R=0.70, which is on the border line between medium and high correlation.

  9. Dominant factors in controlling marine gas pools in South China

    Institute of Scientific and Technical Information of China (English)

    XU Sihuang; W.Lynn Watney

    2007-01-01

    In marine strata from Sinian to Middle Triassic in South China,there develop four sets of regional and six sets of local source rocks,and ten sets of reservoir rocks.The occurrence of four main formation periods in association with five main reconstruction periods,results in a secondary origin for the most marine gas pools in South China.To improve the understanding of marine gas pools in South China with severely deformed geological background,the dominant control factors are discussed in this paper.The fluid sources,including the gas cracked from crude oil,the gas dissolved in water,the gas of inorganic origin,hydrocarbons generated during the second phase,and the mixed pool fluid source,were the most significant control factors of the types and the development stage of pools.The period of the pool formation and the reconstruction controlled the pool evolution and the distribution on a regional scale.Owing to the multiple periods of the pool formation and the reconstruction,the distribution of marine gas pools was complex both in space and in time,and the gas in the pools is heterogeneous.Pool elements,such as preservation conditions,traps and migration paths,and reservoir rocks and facies,also served as important control factors to marine gas pools in South China.Especially,the preservation conditions played a key role in maintaining marine oil and gas accumulations on a regional or local scale.According to several dominant control factors of a pool,the pool-controlling model can be constructed.As an example,the pool-controlling model of Sinian gas pool in Weiyuan gas field in Sichuan basin was summed up.

  10. Dominant factors in controlling marine gas pools in South China

    Science.gov (United States)

    Xu, S.; Watney, W.L.

    2007-01-01

    In marine strata from Sinian to Middle Triassic in South China, there develop four sets of regional and six sets of local source rocks, and ten sets of reservoir rocks. The occurrence of four main formation periods in association with five main reconstruction periods, results in a secondary origin for the most marine gas pools in South China. To improve the understanding of marine gas pools in South China with severely deformed geological background, the dominant control factors are discussed in this paper. The fluid sources, including the gas cracked from crude oil, the gas dissolved in water, the gas of inorganic origin, hydrocarbons generated during the second phase, and the mixed pool fluid source, were the most significant control factors of the types and the development stage of pools. The period of the pool formation and the reconstruction controlled the pool evolution and the distribution on a regional scale. Owing to the multiple periods of the pool formation and the reconstruction, the distribution of marine gas pools was complex both in space and in time, and the gas in the pools is heterogeneous. Pool elements, such as preservation conditions, traps and migration paths, and reservoir rocks and facies, also served as important control factors to marine gas pools in South China. Especially, the preservation conditions played a key role in maintaining marine oil and gas accumulations on a regional or local scale. According to several dominant control factors of a pool, the pool-controlling model can be constructed. As an example, the pool-controlling model of Sinian gas pool in Weiyuan gas field in Sichuan basin was summed up. ?? Higher Education Press and Springer-Verlag 2007.

  11. Dentine sensitivity risk factors: A case–control study

    OpenAIRE

    Mafla, Ana Cristina; Lopez-Moncayo, Luis Fernando

    2016-01-01

    Objective: To identify the clinical and psychological risk factors associated with dentine hypersensitivity (DH) in order to provide an early diagnosis and preventive therapy. Materials and Methods: A nested case–control study was design between 2011 and 2012. A total of 61 DH cases and 122 controls participated in this investigation. Cases and controls were matched for sex, group of age and socioeconomic status in a ratio of 1:2. DH to different stimuli such as cold, heat, acid, and sweet wa...

  12. Climatic and geomorphic controls on the erosion of terrestrial biomass from subtropical mountain forest.

    OpenAIRE

    R. J. Hilton; A. Galy; Niels Hovius; S. J. Kao; Horng, M.J.; Chen, H.;  

    2012-01-01

    [1] Erosion of particulate organic carbon (POC) occurs at very high rates in mountain river catchments, yet the proportion derived recently from atmospheric CO2 in the terrestrial biosphere (POCnon-fossil) remains poorly constrained. Here we examine the transport of POCnon-fossil in mountain rivers of Taiwan and its climatic and geomorphic controls. In 11 catchments we have combined previous geochemical quantification of POC source (accounting for fossil POC from bedrock), with measurements o...

  13. High-efficiency climate control systems with a heat and cold storage unit for electric vehicles

    OpenAIRE

    Nasri, Mounir

    2016-01-01

    Range reduction caused by climate control is a barrier to widespread adoption of electric vehicles (EV). Higher efficiency and lower energy consumption by the air conditioning system will mitigate this disadvantage, as power consumption inside electric vehicles is a very relevant issue. Moreover, several European Union directives prohibit the use of HFC 134a or any other fluorinated greenhouse gas with a Global Warming Potential (GWP) higher than 150 in new mobile air conditioning systems ...

  14. Physiology and Endocrinology Symposium. Factors controlling puberty in beef heifers

    Science.gov (United States)

    The Physiology and Endocrinology Symposium on “Factors controlling puberty in beef heifers” was held at the joint annual meeting of the American Dairy Science Association and the American Society of Animal Science in New Orleans, Louisiana, USA, July 10 to 14, 2011. The objective of the symposium w...

  15. Patient factors and glycaemic control--associations and explanatory power

    DEFF Research Database (Denmark)

    Rogvi, S; Tapager, I; Almdal, T P;

    2012-01-01

    AIMS: To investigate the association between glycaemic control and patient socio-demographics, activation level, diabetes-related distress, assessment of care, knowledge of target HbA(1c), and self-management behaviours, and to determine to what extent these factors explain the variance in HbA(1c...

  16. Responses of Lens esculenta Moench to controlled environmental factors

    NARCIS (Netherlands)

    Saint-Clair, P.M.

    1972-01-01

    Many experiments were undertaken to study the responses of the lentil cultivars 'Large blonde' and 'Anicia' to controlled environmental factors. They covered different aspects of the physiology and the ecology of the crop.The orientation experiments (2) involved germination and depth of sowing. The

  17. The effects of air pollution and climatic factors on atmospheric corrosion of marble under field exposure

    International Nuclear Information System (INIS)

    The atmospheric corrosion of marble was evaluated in terms of SO2 concentration as air pollution and climatic factors such as rainfall, relative humidity, temperature and so on under the field exposure. Marble of calcite type (CaCO3) was exposed to outdoor atmospheric environment with and without a rain shelter at four test sites in the southern part of Vietnam for 3-month, 1- and 2-year periods from July 2001 to September 2003. The thickness loss of marble was investigated gravimetrically. X-ray diffraction and X-ray fluorescent methods were applied to study corrosion products on marble. The corrosion product of marble was only gypsum (CaSO4 . 2H2O) and was washed out by rain under the unsheltered exposure condition. It was found that the most substantial factors influencing the corrosion of marble were rainfall, SO2 concentration in the air and relative humidity. Based on the results obtained, we estimated the dose-response functions for the atmospheric corrosion of marble in the southern part of Vietnam

  18. Designing Simulation Experiments with Controllable and Uncontrollable Factors

    DEFF Research Database (Denmark)

    Dehlendorff, Christian; Kulahci, Murat; Andersen, Klaus Kaae

    In this study we propose a new method for designing computer experiments inspired by the split plot designs used in physical experimentation. The basic layout is that each set of controllable factor settings corresponds to a whole plot for which a number of subplots, each corresponding to one...... should be guaranteed. Our proposed method allows for a large number of uncontrollable and controllable settings to be run in a limited number of runs while uniformly covering the design space for the uncontrollable factors....... combination of settings of the uncontrollable factors, is employed. The caveat is a desire that the subplots within each whole plot cover the design space uniformly. A further desire is that in the combined design, where all experimental runs are considered at once, the uniformity of the design space coverage...

  19. Projecting Future Land Use Changes in West Africa Driven by Climate and Socioeconomic Factors: Uncertainties and Implications for Adaptation

    Science.gov (United States)

    Wang, G.; Ahmed, K. F.; You, L.

    2015-12-01

    Land use changes constitute an important regional climate change forcing in West Africa, a region of strong land-atmosphere coupling. At the same time, climate change can be an important driver for land use, although its importance relative to the impact of socio-economic factors may vary significant from region to region. This study compares the contributions of climate change and socioeconomic development to potential future changes of agricultural land use in West Africa and examines various sources of uncertainty using a land use projection model (LandPro) that accounts for the impact of socioeconomic drivers on the demand side and the impact of climate-induced crop yield changes on the supply side. Future crop yield changes were simulated by a process-based crop model driven with future climate projections from a regional climate model, and future changes of food demand is projected using a model for policy analysis of agricultural commodities and trade. The impact of human decision-making on land use was explicitly considered through multiple "what-if" scenarios to examine the range of uncertainties in projecting future land use. Without agricultural intensification, the climate-induced decrease of crop yield together with increase of food demand are found to cause a significant increase in agricultural land use at the expense of forest and grassland by the mid-century, and the resulting land use land cover changes are found to feed back to the regional climate in a way that exacerbates the negative impact of climate on crop yield. Analysis of results from multiple decision-making scenarios suggests that human adaptation characterized by science-informed decision making to minimize land use could be very effective in many parts of the region.

  20. MODELLING THE POTENTIAL IMPACTS OF GLOBAL CLIMATE CHANGE IN BANGLADESH: AN OPTIMAL CONTROL APPROACH

    Directory of Open Access Journals (Sweden)

    H. A. Biswas

    2016-01-01

    Full Text Available One of the most hot issues in the recent environmental research worldwide has become the harmful effects of climate change on the ecosystems and environment due to global warming. Bangladesh is one of the most vulnerable countries not only in the South East Asia but also in the world. It is predicted that a large portion of the South-western region of Bangladesh will go under sea in the next 50 to 100 years due to sea level rise. In this paper, we first discuss some potential impacts of climate change in Bangladesh and its aftermath on the ecosystems and secondly, we study a mathematical model of climate change in terms of ordinary differential equations (ODEs and apply optimal control techniques in the form of Pontryagin Maximum Principle (PMP to investigate the control strategy of greenhouse gases (GHGs. We study the model numerically using some known nonlinear ‘optimal control solvers’ and the results are illustrated with numerical simulations.

  1. Impact of climate change on factors relevant to probable maximum precipitation estimates

    International Nuclear Information System (INIS)

    Full text: Full text: Large-scale civil engineering works are often designed with reference to the probable maximum precipitation (PMP) design flood, in which one required input is the PMP estimate for a particular catchment. The PMP is the greatest depth of precipitation meteorologically possible for a given duration, area, location and time of year, with no allowance made for long-term climatic trends. PMP estimates are derived for any catchment in Australia using an appropriate generalised method. Each method relies on a catalogue of previous significant rainfall events of various areas and durations for a particular application zone. The PMP rainfall depth is derived from the upper bound of the maximised-standardised convergence rainfall, in which the available moisture for each event has been maximised to its climatological extreme and all events standardised to a common location. The event associated with the PMP rainfall depth (for a particular area and duration) is also assumed to operate at an optimal efficiency. The PMP estimates, although assumed to be independent of climate change, are likely to be influenced by changes in factors contributing to moisture availability (through both storm and extreme precipitable water) and relative storm efficiency (the ratio of rainfall rate to storm precipitable water). Analyses indicate that changes in extreme precipitable water will have the most direct impact on PMP estimates when applied to a particular catchment. The CSIRO Mk3.0 climate model was used to assess for changes in the 90th percentile of precipitable water for different emission scenarios up to the year 2100. These changes indicate that extreme precipitable water will increase for most seasons and locations across Australia that have been associated with previous significant rainfall events. However when assessing the effect of changes, an additional complication results from the transposition process within the generalised methods. There is a

  2. Climatic influences on development and survival of free-living stages of equine strongyles: implications for worm control strategies and managing anthelmintic resistance.

    Science.gov (United States)

    Nielsen, Martin K; Kaplan, Ray M; Thamsborg, Stig M; Monrad, Jesper; Olsen, Susanne N

    2007-07-01

    Development of resistance to anthelmintic drugs by horse strongyles constitutes a growing threat to equine health because it is unknown when new drug classes can be expected on the market. Consequently, parasite control strategies should attempt to maintain drug efficacy for as long as possible. The proportion of a parasite population that is not exposed to anthelmintic treatment is described as being "in refugia" and although many factors affect the rate at which resistance develops, levels of refugia are considered the most important as these parasites are not selected by treatment and so provide a pool of sensitive genes in the population. Accordingly, treatment should be avoided when pasture refugia are small because such treatments will place significant selection pressure for resistance on worm populations. Given this new paradigm for parasite control, it has become important to identify seasons and circumstances wherein refugia are diminished. Free-living stages of equine strongyles are highly dependent on climatic influences, and this review summarises studies of strongyle development and survival under laboratory and field conditions in Northern (cool) temperate, Southern (warm) temperate and subtropical/tropical climates. In Northern temperate climates, refugia are smallest during the winter. In contrast, refugia are lowest during the summer in warm temperate and subtropical/tropical climates. Although adverse seasonal changes clearly have significant effects on the ability of free living stages of strongyle nematode parasites to survive and develop, available data suggest that climatic influences cannot effectively "clean" pastures from one grazing season to the next. PMID:16815051

  3. Internal Roof and Attic Thermal Radiation Control Retrofit Strategies for Cooling-Dominated Climates

    Energy Technology Data Exchange (ETDEWEB)

    Fallahi, A. [Fraunhofer Center for Sustainable Energy Systems, Boston, MA (United States); Duraschlag, H. [Fraunhofer Center for Sustainable Energy Systems, Boston, MA (United States); Elliott, D. [Fraunhofer Center for Sustainable Energy Systems, Boston, MA (United States); Hartsough, J. [Fraunhofer Center for Sustainable Energy Systems, Boston, MA (United States); Shukla, N. [Fraunhofer Center for Sustainable Energy Systems, Boston, MA (United States); Kosny, J. [Fraunhofer Center for Sustainable Energy Systems, Boston, MA (United States)

    2013-12-01

    This project evaluates the cooling energy savings and cost effectiveness of radiation control retrofit strategies for residential attics in U.S. cooling-dominated climates. Usually, in residential applications, radiation control retrofit strategies are applied below the roof deck or on top of the attic floor insulation. They offer an alternative option to the addition of conventional bulk insulation such as fiberglass or cellulose insulation. Radiation control is a potentially low-cost energy efficiency retrofit strategy that does not require significant changes to existing homes. In this project, two groups of low-cost radiation control strategies were evaluated for southern U.S. applications. One uses a radiant barrier composed of two aluminum foils combined with an enclosed reflective air space and the second uses spray-applied interior radiation control coatings (IRCC).

  4. Internal Roof and Attic Thermal Radiation Control Retrofit Strategies for Cooling-Dominated Climates

    Energy Technology Data Exchange (ETDEWEB)

    Fallahi, A. [Fraunhofer Center for Sustainable Energy Systems (CSE), Boston, MA (United States); Durschlag, H. [Fraunhofer Center for Sustainable Energy Systems (CSE), Boston, MA (United States); Elliott, D. [Fraunhofer Center for Sustainable Energy Systems (CSE), Boston, MA (United States); Hartsough, J. [Fraunhofer Center for Sustainable Energy Systems (CSE), Boston, MA (United States); Shukla, N. [Fraunhofer Center for Sustainable Energy Systems (CSE), Boston, MA (United States); Kosny, J. [Fraunhofer Center for Sustainable Energy Systems (CSE), Boston, MA (United States)

    2013-12-01

    This project evaluates the cooling energy savings and cost effectiveness of radiation control retrofit strategies for residential attics in U.S. cooling-dominated climates. Usually, in residential applications, radiation control retrofit strategies are applied below the roof deck or on top of the attic floor insulation. They offer an alternative option to the addition of conventional bulkinsulation such as fiberglass or cellulose insulation. Radiation control is a potentially low-cost energy efficiency retrofit strategy that does not require significant changes to existing homes. In this project, two groups of low-cost radiation control strategies were evaluated for southern U.S. applications. One uses a radiant barrier composed of two aluminum foils combined with an enclosedreflective air space and the second uses spray-applied interior radiation control coatings (IRCC).

  5. An Examination of Bullying in Georgia Schools: Demographic and School Climate Factors Associated with Willingness to Intervene in Bullying Situations

    OpenAIRE

    Goldammer, Lori; Swahn, Monica; Strasser, Sheryl; Ashby, Jeffrey; Meyers, Joel

    2013-01-01

    Introduction: Research dedicated to identification of precursors to cases of aggravated bullying in schools has led to enhanced knowledge of risk factors for both victimization and perpetration. However, characteristics among those who are more likely to intervene in such situations are less understood. The purpose of this study is to examine the associations between demographic characteristics, school climate and psychosocial factors, and willingness to intervene in a bullying situation amon...

  6. Expedient parameters of deep horizon mining in respect to climatic factors

    Energy Technology Data Exchange (ETDEWEB)

    Kuzin, V.A.; Martynov, A.A.

    1988-01-01

    Studies on forecasting thermal conditions in 670-1026 m deep workings were conducted at 8 mines in the central Donbass region. In these workings rock mass temperature, air temperature and air humidity were 30-40 C, 25.2-30.7 C and 82-100% respectively. Presents methods of temperature forecasting and control. It was established that development working with grouping of adjacent seams into field segments according to formation of climatic conditions is the most suitable method. By grouping worked seams, the temperature at longwall entrances can be lowered by 0.9-1.6 C compared to workings with individual headings. When more seams (three or more) are grouped together, air temperature at longwall entrances can be lowered by 1.2-2.6 C. Reduction in distances between cross cuts from 750 to 300 m provides a further temperature decrease of 0.4-0.7 C. Recommends increasing air flow rate and cross section areas of ventilation headings from 3.5-6 m/sup 3//s to 8 m/sup 3//s and from 4.6 m/sup 2/ to 6.1 m/sup 2/ respectively. Concludes that under conditions similar to those prevailing in the central Donbass region the following measures can be recommended: technological schemes with excavation by strips to the dip; increased cross-sectional areas of workings; roof control by stowing, especially using cooled backfilling material; preventing ventilation air from escaping through excavated space.

  7. REPRODUCTIVE FACTORS AND COLORECTAL CANCER RISK. Case - control study.

    Directory of Open Access Journals (Sweden)

    Adriana Ruseva

    2015-02-01

    Full Text Available Colorectal cancer is one of the most common cancers worldwide. The role of the female sex hormones in the etiology of the disease is very intriguing. Reproductive factors are surrogate measure of lifetime exposition to the sex hormones. Purpose: Our aim is to investigate the association between the reproductive factors and colorectal carcinoma risk. Materials and methods: We include 234 Bulgarian women in our study – 117 cases with colorectal cancer and the same number of healthy controls. Cases are divided into three groups according to the localization of the tumor. We conduct case-control study, using questionnaires about reproductive factors. We use the following statistical methods – descriptive, variational analysis, binary logistic regression. Results: We observed that only the age at menopause is associated with colorectal cancer risk, and this factor has strongest protective effect in the proximal colon (95% CI - 0,051-0,781, OR – 0,200, p – 0,021. Conclusion: Analyzing our data we observed that among Bulgarian women the only reproductive factor that show association with the risk of colorectal cancer is the age at menopause.

  8. Goldilocks and three factors that make mercury in fish more than just mercury deposition: sulfur, land use and climate (Invited)

    Science.gov (United States)

    Bishop, K. H.; Eklöf, K.; Nilsson, M. B.; Osterwalder, S.; Åkerblom, S.

    2013-12-01

    The problem of mercury in fish is often framed as a problem created by anthropogenic emissions of mercury increasing the levels of mercury in the environment. But the methylation step that is crucial to making mercury available for bioaccumulation in the aquatic food web is influenced by more than just the concentration of mercury in the environment. Redox conditions, the quality of organic matter, and, in the case of methylation by sulfur reducing bacteria, the availability of sulfur, have all been shown to influence methylmercury concentrations in surface waters and/or mercury in the biota. This creates many possibilities for human influence on mercury bioaccumulation in freshwater fish. But it also creates possibilities for mitigating those human influences, if we can understand them. Forest harvest is one type of land use with a documented human influence on mercury levels in fish. Atmospheric deposition of sulfur is another potential influence on the mercury cycle, as is warming of the climate. Some for the possibilities for controlling the mercury problem may be overlooked by too much focus on mercury deposition and concentrations of total mercury in the landscape relative to these other factors. A range of field studies in FennoScandia published over the last 15 years were analyzed to explore the relative contribution of these different anthropogenic factors on the cycling of mercury. The studies included synoptic surveys across gradients of atmospheric deposition and land use (clear felling, site preparation and stump harvest) in relation to either fish mercury, sediment mercury, peat methylation potential or methylmercury concentrations in water. Long-term field manipulations (6-15 years) of land use (forest harvest) or combinations of sulphur deposition, nitrogen deposition and well greenhouse warming on peatland were also studied. The results suggest that the variation of total mercury in soils or water is less important than several of the other factors

  9. Factores de necesidad asociados al uso adecuado del control prenatal

    Directory of Open Access Journals (Sweden)

    Clarybel Miranda Mellado

    2016-07-01

    Full Text Available Introducción: Por las implicaciones sociales de la mortalidad y morbilidad materna es importante determinar los factores de necesidad que influyen en el uso adecuado del control prenatal en gestantes de Sincelejo. Materiales y Métodos: Estudio analítico de corte transversal, que incluyó 730 gestantes, seleccionadas mediante muestreo aleatorio por conglomerados, de las comunas de la ciudad. La información fue recolectada por medio de una encuesta sociodemográfica, una ficha de uso de control prenatal y un Cuestionario para evaluar los factores de necesidad  propuestos por el Modelo de Promoción de la Salud de Nola Pender. Las gestantes fueron contactadas en sus domicilios y diligenciaron los instrumentos. Los datos fueron analizados aplicando estadística descriptiva e inferencial para determinar las asociaciones entre variables. Resultados: El 97,7% (713 de las gestantes asistía al control prenatal, con una mediana de 4 controles prenatales. Un 2,3% (17 no lo habían iniciado al momento de la encuesta y 24,4% (178 hizo uso inadecuado. El 80,7% (589 de las gestantes califican su estado de salud como bueno o muy bueno, 94,8% (692 percibieron beneficios del control prenatal. Se encontró asociación significativa entre la percepción de beneficios y el uso adecuado de control prenatal [OR=5,5 (IC 95%: 2,8 - 10,8]. Discusión y Conclusiones: La percepción que las mujeres tienen sobre los buenos resultados que reporta la asistencia al control prenatal, es el principal factor que puede explicar la adherencia al control y el cumplimiento regular de las consultas. Cómo citar este artículo: Miranda C, Castillo IY. Factores de necesidad asociados al uso adecuado del control prenatal. Rev Cuid. 2016; 7(2: 1345-51. http://dx.doi.org/10.15649/cuidarte.v7i2.340

  10. An Examination of Bullying in Georgia Schools: Demographic and School Climate Factors Associated with Willingness to Intervene in Bullying Situations

    Directory of Open Access Journals (Sweden)

    Lori Goldammer

    2013-08-01

    Full Text Available Introduction: Research dedicated to identification of precursors to cases of aggravated bullying in schools has led to enhanced knowledge of risk factors for both victimization and perpetration. However, characteristics among those who are more likely to intervene in such situations are less understood. The purpose of this study is to examine the associations between demographic characteristics, school climate and psychosocial factors, and willingness to intervene in a bullying situation among middle and high school students in Georgia.Methods: We computed analyses using cross-sectional data from the Georgia Student Health Survey II (GSHS 2006 administered to public school students in grades 6, 8, 10, and 12 (n=175,311. We used logistic regression analyses to determine the demographic, school climate and psychosocial factors associated with a willingness to intervene in a bullying situation.Results: Students who were white and who were girls were most likely to report willingness to intervene in bullying situations. Several school-climate factors, such as feeling safe at school, liking school, feeling successful at school and perceiving clear rules at school, were associated with willingness to intervene, while youth who reported binge drinking were less willing to intervene.Conclusion: These findings, while preliminary, indicate that girls, students who are white, and students who experience a relatively positive school climate and adaptive psychosocial factors are more likely to report that they would intervene in bullying situations. These findings may guide how bullying is addressed in schools and underscore the importance of safe school climates. [West J Emerg Med. 2013;14(4:324–328.

  11. The adaptation rate of terrestrial ecosystems as a critical factor in global climate dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Fuessler, J.S.; Gassmann, F. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    A conceptual climate model describing regional two-way atmosphere-vegetation interaction has been extended by a simple qualitative scheme of ecosystem adaptation to drought stress. The results of this explorative study indicate that the role of terrestrial vegetation under different forcing scenarios depends crucially on the rate of the ecosystems adaptation to drought stress. The faster the adaptation of important ecosystems such as forests the better global climate is protected from abrupt climate changes. (author) 1 fig., 3 refs.

  12. Factores de necesidad asociados al uso adecuado del control prenatal

    OpenAIRE

    Clarybel Miranda Mellado; Irma Castillo Avila

    2016-01-01

    Introducción: Por las implicaciones sociales de la mortalidad y morbilidad materna es importante determinar los factores de necesidad que influyen en el uso adecuado del control prenatal en gestantes de Sincelejo. Materiales y Métodos: Estudio analítico de corte transversal, que incluyó 730 gestantes, seleccionadas mediante muestreo aleatorio por conglomerados, de las comunas de la ciudad. La información fue recolectada por medio de una encuesta sociodemográfica, una ficha de uso de control p...

  13. The response to climate factors for the different specificity in M2 physiology of 60Co γ-ray irradiated flowers

    International Nuclear Information System (INIS)

    Physiology and climate factor of different M2 flower (Begonia tuberhybrida Voss and Dahlia pinnata Cav root) after 60Co γ-ray irradiated were determined. The result showed that transpiration rate, stoma conductance, intercellular CO2 concentration of M2 of Dahlia pinnata Cav are affected obviously with climate factors, however, effect on the photosynthetic speed was not found, and M2 of Begonia tuberhybrida Voss was not significant for physiology to climate

  14. Soil chemical weathering under morphologic and climatic controls in the Northern Rockies, Montana

    Science.gov (United States)

    Benjaram, S. S.; Dixon, J. L.

    2015-12-01

    Climate influences soil weathering via moisture availability and temperatures, but globally physical erosion rate appears to be a more important control on weathering rate than climate. Understanding these links requires investigation into landscapes where the climate's influence on weathering is discernable despite the signal of physical erosion rate—in kinetically limited regimes. However, in these systems, rapid erosion rates and complex morphologies add complexity and heterogeneity to soil weathering. To investigate the dual controls of landscape morphology and climate on chemical weathering, we quantify soil distribution, thickness, and weathering extent by focusing on catchments within two adjacent mountain ranges in the Northern Rockies. The Bitterroot Mtns present previously-glaciated valleys with steep ridges and high present-day MAP, which contrast with the drier and more gentle, nonglaciated hillslopes of the Sapphire Mtns to the east. We use field and remotely sensed data to quantify soil distribution and thickness, and elemental geochemistry to measure the variability of chemical weathering across these systems.Mean slopes in the Bitterroots are ~1.3x higher than those in our Sapphire catchment, leading to large differences in soil distribution. Initial mapping of soils using remotely sensed data and rock exposure indices (REI) indicate that ~50% of the Bitterroot system is bare of soil, compared to XRF data suggest soil weathering intensity is more than two times greater in the Sapphires. These results suggest that the morphologic landscape legacy left by now-extinct glaciers imposes a kinetic limitation on soil weathering, even despite high modern moisture availability.

  15. Mechanisms Controlling the Effects of Weather and Climate on California's Ecosystems (Invited)

    Science.gov (United States)

    Goulden, M.; Kelly, A. E.; Fellows, A.; Winston, G.

    2010-12-01

    We combined observations and manipulations along topographic gradients in southern and central California to understand how climate controls ecosystem function. California's topography causes large temperature and precipitation gradients as a result of orographic, rain-shadow, atmospheric lapse, and sea breeze effects. These gradients lead to a wide diversity of ecosystem types and provide a natural laboratory for understanding the controls on plant community composition and ecosystem function. Findings include: (1) Natural climate gradients drive large changes in species composition, plant phenology, growing season length, and primary production. The growing season at low, dry, and warm locations is limited by summer drought, resulting in low primary production. The growing season at high, wet, and cold locations is limited by winter cold, resulting in low primary production. The growing season at mid elevation is limited by neither summer drought nor winter cold, resulting in year-round and high primary production. (2) The relative importance of plant species within a community shifts rapidly in response to changes in water input, caused by either natural variability or experimental manipulation. Species that are intolerant of drier conditions decline rapidly with reduced water input, and may disappear locally; species that are tolerant of drier conditions increase rapidly in extent. (3) Inward plant migration, and the establishment of new species at a location, is a comparatively slow process. The initial phases of climate change will likely reshuffle the importance of existing species within the community, resulting in only modest changes in ecosystem function but possibly extirpating species that are intolerant of warmer and drier conditions, and reducing biodiversity. These declines in biodiversity and delays in species immigration may ultimately limit the ability of ecosystems to respond to subsequent interannual and decadal variations in weather, and to

  16. Controlling for gene expression changes in transcription factor protein networks.

    Science.gov (United States)

    Banks, Charles A S; Lee, Zachary T; Boanca, Gina; Lakshminarasimhan, Mahadevan; Groppe, Brad D; Wen, Zhihui; Hattem, Gaye L; Seidel, Chris W; Florens, Laurence; Washburn, Michael P

    2014-06-01

    The development of affinity purification technologies combined with mass spectrometric analysis of purified protein mixtures has been used both to identify new protein-protein interactions and to define the subunit composition of protein complexes. Transcription factor protein interactions, however, have not been systematically analyzed using these approaches. Here, we investigated whether ectopic expression of an affinity tagged transcription factor as bait in affinity purification mass spectrometry experiments perturbs gene expression in cells, resulting in the false positive identification of bait-associated proteins when typical experimental controls are used. Using quantitative proteomics and RNA sequencing, we determined that the increase in the abundance of a set of proteins caused by overexpression of the transcription factor RelA is not sufficient for these proteins to then co-purify non-specifically and be misidentified as bait-associated proteins. Therefore, typical controls should be sufficient, and a number of different baits can be compared with a common set of controls. This is of practical interest when identifying bait interactors from a large number of different baits. As expected, we found several known RelA interactors enriched in our RelA purifications (NFκB1, NFκB2, Rel, RelB, IκBα, IκBβ, and IκBε). We also found several proteins not previously described in association with RelA, including the small mitochondrial chaperone Tim13. Using a variety of biochemical approaches, we further investigated the nature of the association between Tim13 and NFκB family transcription factors. This work therefore provides a conceptual and experimental framework for analyzing transcription factor protein interactions.

  17. Risk Factors For Coronary Heart Disease : A Case Control Study

    Directory of Open Access Journals (Sweden)

    Zodpey Sanjay P

    1998-01-01

    Full Text Available Research question: What is the role of different risk factors in causation of CHD. Objective: To identify the risk factors contributing to the outcome of CHD. Design: Pair matched case-control study. Setting: Government Medical college, Nagpur, India, a tertiary care hospital. Participants: The study included 294 incident cases of CHD diagnosed by standard criteria. Each case was pair matched with one control for age and sex. Controls were selected from subjects attending the hospital for conditions other than CHD. Main Outcome Measure: CHD. Study variable: Socio-economic status (SES, physical inactivity (PI, family history of CHD, type A personality (TAP, cigarette smoking (CS, alcohol consumption (AC, obesity, oral contraceptive use (OC use, diabetes mellitus (DM, hypertension (HT and total serum cholesterol TSC. Results: On univariate analysis all the 11 risk factors were significantly associated with CHD. Conditional multiple logistic regression identified significant association of SES (OR 2.92, 95% CI 2.28-3.73, PI (OR 2.03, 95% CI 1.56-2.62, OC use (OR 3.96, 95% CI 1.11-14.02, obesity (OR 1.62, 95% CI 1.15-2.27, DM (OR 2.17, 95% CI 1.13-4.13, HT (OR 4.23, 95% CI 2.56-6399, TSC (OR 3.84, 95% CI 2.58-5.72 and CHD. Estimates of attributable risk proportion and population attributable risk proportion for the significant factors confirmed their etiological role and impact of these factors on the development of CHD in this population. Conclusion: This study identified significance of SES, PI, OC use, obesity, DM, HT and TSC in multivariate environment in the outcome of CHD.

  18. The role of climatic factors in evolving flood patterns in a Mediterranean Region (1301–2012

    Directory of Open Access Journals (Sweden)

    A. Barrera-Escoda

    2014-08-01

    Full Text Available Data on flood occurrence and flood impacts for the last seven centuries in the northeast Iberian Peninsula have been analysed in order to characterise long-term trends, anomalous periods and their relationship with different climatic factors such as precipitation, general circulation and solar activity. Catastrophic floods do not present a statistically significant trend, whereas extraordinary floods have seen a significant rise, especially from 1850 on, and were responsible for the total increase in flooding in the region. This rise can be mainly attributed to small coastal catchments, which have experienced a marked increase in developed land and population, resulting in changes in land use and greater vulnerability. Changes in precipitation alone cannot explain the variation in flood patterns, although a certain increase was shown in late summer–early autumn, when extraordinary floods are most frequently recorded. The relationship between North Atlantic circulation and floods is not as strong, due to the important role of mesoscale factors in heavy precipitation in the northwest of the Mediterranean region. However it can explain the variance to some extent, mainly in relation to the catastrophic floods experienced during the autumn. Solar activity has some impact on changes in catastrophic floods with cycles related to the Quasi-Biennial Oscillation and the Gleissberg solar cycle. In addition, anomalous periods of high flood frequency in autumn generally occurred during periods of increased solar activity. The physical influence of the latter in general circulation patterns, the high troposphere and the stratosphere, has been analysed in order to ascertain its role in causing floods.

  19. Land cover or climate? In search of dominant factors inducing groundwater recharge and fen hydrology in European scale

    Science.gov (United States)

    Grygoruk, Mateusz; Kotowski, Wiktor

    2016-04-01

    Groundwater recharge plays the crucial role in development and stability of fens. It was hypothesized that the mid- and late-Holocene acceleration of fens' development in Europe could have been induced by changes in land cover: decreasing areas of forests resulting from the expanding agriculture have enhanced groundwater recharge by decreasing evapotranspiration and interception and promoting infiltration. However, regardless human-related changes of the landscape, recorded climatic fluctuations could also be considered as drivers of changing groundwater recharge that affects fen stability and development. Nowadays, when up to 90% of European wetlands is considered degraded, assessing vulnerability of groundwater recharge to changing landscape and climate is of the crucial importance for setting fen restoration and management strategies. Main goal of our study was to assess the magnitude of changes in groundwater recharge estimation resulting from modelled changes of the landscape and climatic features in >300 fens located in Poland, Germany, The Netherlands, Sweden, UK and Norway. In our approach we (1) delineated the most probable extents of catchments of particular fens analysed, (2) assumed hypothetical and the most probable changes of land cover within these catchments, (3) assumed the most probable ranges of climatic changes in each of the catchments including historical reconstructions (Holocene) and future projections (A1B scenario, CSIRO:MK3 and UKMO:HADCM3 GCM-RCM ensembles), (4) developed, tested and calibrated automatic, GIS-based groundwater recharge calculation algorithm to be applied in the study, (5) calculated groundwater recharge in multiple probable combinations of landscape and climatic conditions and (6) performed statistical analysis in order to reveal whether the climate or landscape changes were the dominant factors that could have probably influenced groundwater recharge in catchments of fens analysed. We revealed that in the case of 80% of

  20. Predictive factors of seizure control in childhood onset epilepsy

    OpenAIRE

    Eli Shahar; Jacob Genizi

    2008-01-01

    Background: Prediction of the long-term outcomes of childhood-onset epilepsy remains crucial for the future well-being of the affected children and their families and for planning proper therapeutic and educational programs. Objective: To identify and analyze the early predictive factors of seizure control in childhood-onset epilepsies referred at the age of 1 month up to the age of 18 years to the Epilepsy Service at the Meyer Children Hospital, Rambam Medical Center, Haifa, Israel. Materia...

  1. Macrophage migration inhibitory factor: controller of systemic inflammation

    OpenAIRE

    Larson, Douglas F.; Horak, Katherine

    2006-01-01

    Macrophage migration inhibitory factor (MIF) is a cytokine that is secreted by the anterior pituitary and immune cells in response to surgical stress, injury, and sepsis. This cytokine appears to be a critical regulator of the inflammatory pathways, leading to systemic inflammatory response syndrome and subsequent multiple organ dysfunction syndrome. This report provides an integrated scheme describing the manner by which MIF controls the neurohormonal response and the adaptive immune system,...

  2. Warming climate extends dryness-controlled areas of terrestrial carbon sequestration

    Science.gov (United States)

    Yi, Chuixiang; Wei, Suhua; Hendrey, George

    2014-01-01

    At biome-scale, terrestrial carbon uptake is controlled mainly by weather variability. Observational data from a global monitoring network indicate that the sensitivity of terrestrial carbon sequestration to mean annual temperature (T) breaks down at a threshold value of 16°C, above which terrestrial CO2 fluxes are controlled by dryness rather than temperature. Here we show that since 1948 warming climate has moved the 16°C T latitudinal belt poleward. Land surface area with T > 16°C and now subject to dryness control rather than temperature as the regulator of carbon uptake has increased by 6% and is expected to increase by at least another 8% by 2050. Most of the land area subjected to this warming is arid or semiarid with ecosystems that are highly vulnerable to drought and land degradation. In areas now dryness-controlled, net carbon uptake is ~27% lower than in areas in which both temperature and dryness (T 16°C has implications not only for positive feedback on climate change, but also for ecosystem integrity and land cover, particularly for pastoral populations in marginal lands. PMID:24980649

  3. Factors Controlling the Distribution of Trace Metals in Macroalgae

    Institute of Scientific and Technical Information of China (English)

    王宝利; 刘丛强

    2004-01-01

    This paper presents the concentrations of trace metals (Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, Pb) in macroalgae from five areas. Significant differences were noticed in trace metal concentration in macroalgae, and a large range of variations between the minimum and maximum concentrations of trace metals was found. Trace metals detected in macroalgae generally occur in adsorbed and absorbed forms. Environmental and biological factors jointly control the trace metal compositions and concentrations in macroalgae. The complexity and variation of these factors cause significant differences in trace metal concentrations in macroalgae. Environmental factors play a more important role in controlling trace metal compositions and concentrations when external available trace metals are beyond requirement for algal metabolism and growth, especially for non-essential trace metals; however, when the external available trace metals just satisfy the needs of algal metabolism and growth, biological factors would play a more important role, especially for essential trace metals. Interactions among the trace metals can also influence their compositions and concentrations in macroalgae. It is also discussed how to make macroalgae as an excellent biomonitor for trace metals.

  4. Effects of Environmental Factors on the Disinfection Performance of a Wastewater Stabilization Pond Operated in a Temperate Climate

    Directory of Open Access Journals (Sweden)

    Lei Liu

    2015-12-01

    Full Text Available Treatment in a wastewater stabilization pond (WSP relies on natural purification processes, which can be sensitive to both location and climate. This study investigated the effects of three environmental factors, pH, dissolved oxygen (DO and temperature, on disinfection efficiency in a WSP system consisting of three facultative cells, and operated in a temperate climate region, in Eastern Ontario, Canada. Indicator organism (Escherichia coli (E. coli removal in WSP systems is driven by a combination of different factors. Elevated pH and DO concentrations, which are attributed to the presence of algae, are important factors for effective disinfection. Therefore, the presence of algae in natural wastewater treatment systems can contribute appreciably to disinfection. Consequently, based on algal concentrations, removal efficiencies of pathogenic microorganisms during wastewater treatment over the course of a year can be highly variable, where higher removal efficiencies would be expected in summer and fall seasons.

  5. Control factors and scale analysis of annual river water, sediments and carbon transport in China

    Science.gov (United States)

    Song, Chunlin; Wang, Genxu; Sun, Xiangyang; Chang, Ruiying; Mao, Tianxu

    2016-05-01

    Under the context of dramatic human disturbances on river system, the processes that control the transport of water, sediment, and carbon from river basins to coastal seas are not completely understood. Here we performed a quantitative synthesis for 121 sites across China to find control factors of annual river exports (Rc: runoff coefficient; TSSC: total suspended sediment concentration; TSSL: total suspended sediment loads; TOCL: total organic carbon loads) at different spatial scales. The results indicated that human activities such as dam construction and vegetation restoration might have a greater influence than climate on the transport of river sediment and carbon, although climate was a major driver of Rc. Multiple spatial scale analyses indicated that Rc increased from the small to medium scale by 20% and then decreased at the sizable scale by 20%. TSSC decreased from the small to sizeable scale but increase from the sizeable to large scales; however, TSSL significantly decreased from small (768 g·m-2·a-1) to medium spatial scale basins (258 g·m-2·a-1), and TOCL decreased from the medium to large scale. Our results will improve the understanding of water, sediment and carbon transport processes and contribute better water and land resources management strategies from different spatial scales.

  6. Control factors and scale analysis of annual river water, sediments and carbon transport in China

    Science.gov (United States)

    Song, Chunlin; Wang, Genxu; Sun, Xiangyang; Chang, Ruiying; Mao, Tianxu

    2016-05-01

    Under the context of dramatic human disturbances on river system, the processes that control the transport of water, sediment, and carbon from river basins to coastal seas are not completely understood. Here we performed a quantitative synthesis for 121 sites across China to find control factors of annual river exports (Rc: runoff coefficient; TSSC: total suspended sediment concentration; TSSL: total suspended sediment loads; TOCL: total organic carbon loads) at different spatial scales. The results indicated that human activities such as dam construction and vegetation restoration might have a greater influence than climate on the transport of river sediment and carbon, although climate was a major driver of Rc. Multiple spatial scale analyses indicated that Rc increased from the small to medium scale by 20% and then decreased at the sizable scale by 20%. TSSC decreased from the small to sizeable scale but increase from the sizeable to large scales; however, TSSL significantly decreased from small (768 g·m‑2·a‑1) to medium spatial scale basins (258 g·m‑2·a‑1), and TOCL decreased from the medium to large scale. Our results will improve the understanding of water, sediment and carbon transport processes and contribute better water and land resources management strategies from different spatial scales.

  7. A Geographic Perspective on Factors Controlling Post-Fire Succession in Boreal Black Spruce Forests in Western North America

    Science.gov (United States)

    Kasischke, E. S.; Kane, E. S.; Genet, H.; Turetsky, M. R.; ODonnell, J. A.; Hoy, E.; Barrett, K.; Baltzer, J. L.

    2014-12-01

    Recent changes to climate and the fire regime have resulted in a number of distinct changes to patterns of post-fire succession in the boreal forest region of western North America. In interior Alaska and Yukon, these responses include a shift from spruce to deciduous dominated forests in black spruce forests that experienced exposure of mineral soils from deep burning of surface organic soils, as well as low seedling recruitment in white spruce forests as a result of moisture stress. In this presentation, we will use a physical geography framework to analyze factors controlling low seedling recruitment in recently burned black spruce forests in Alaska. This approach allows for understanding how changes in the biologic components of black spruce forest ecosystems (e.g., biogeography) are controlled by factors related to geomorphology and climate over multiple spatial and temporal scales. In particular, this framework will be used to examine how the interactions between fire, climate, topography and soil texture influence pre-fire and post-fire permafrost conditions, which interact to have a strong influence on variations in soil moisture. In turn, recent changes to climate combined with variations in soil moisture controlled by differences in permafrost conditions (ground ice content, active layer thickness) can be used to explain variations in post-fire seedling recruitment in black spruce forests, where low recruitment is occurring on the sites with the driest soils. In addition, we will examine the need for further research in other boreal forest regions of western North America where the presence of pine species (jack and lodgepole) that are absent in Alaska, as well as differences in soils and permafrost conditions, are likely resulting in additional patterns of post-fire succession as a result of recent changes to climate and the fire regime.

  8. Can climate change jeopardize predator control of invasive herbivore species? A case study in avocado agro-ecosystems in Spain.

    Science.gov (United States)

    Montserrat, Marta; Sahún, Rosa María; Guzmán, Celeste

    2013-02-01

    Climate change is one of the most important factors affecting the phenology, distribution, composition and diversity of organisms. In agricultural systems many pests and natural enemies are arthropods. As poikilotherm organisms, their body temperature is highly dependent on environmental conditions. Because higher trophic levels typically have lower tolerance to high temperatures than lower trophic levels, trends towards increasing local or regional temperatures may affect the strength of predator/prey interactions and disrupt pest control. Furthermore, increasing temperatures may create climate corridors that could facilitate the invasion and establishment of invasive species originating from warmer areas. In this study we examined the effect of environmental conditions on the dynamics of an agro-ecosystem community located in southern Spain, using field data on predator/prey dynamics and climate gathered during four consecutive years. The study system was composed of an ever-green tree species (avocado), an exotic tetranychid mite, and two native species of phytoseiid mites found in association with this new pest. We also present a climatological analysis of the temperature trend in the area of study during the last 28 years, as evidence of temperature warming occurring in the area. We found that the range of temperatures with positive per capita growth rates was much wider in prey than in predators, and that relative humidity contributed to explain the growth rate variation in predators, but not in prey. Predator and prey differences in thermal performance curves could explain why natural enemies did not respond numerically to the pest when environmental conditions were harsh.

  9. Combined climate factors alleviate changes in gross soil nitrogen dynamics in heathlands

    DEFF Research Database (Denmark)

    Bjorsne, Anna-Karin; Rutting, Tobias; Ambus, Per

    2014-01-01

    The ongoing climate change affects biogeochemical cycling in terrestrial ecosystems, but the magnitude and direction of this impact is yet unclear. To shed further light on the climate change impact, we investigated alterations in the soil nitrogen (N) cycling in a Danish heathland after 5 years...

  10. Understanding disease control: influence of epidemiological and economic factors

    CERN Document Server

    Oles, Katarzyna; Kleczkowski, Adam

    2011-01-01

    We present a local spread model of disease transmission on a regular network and compare different control options ranging from treating the whole population to local control in a well-defined neighborhood of an infectious individual. Comparison is based on a total cost of epidemic, including cost of palliative treatment of ill individuals and preventive cost aimed at vaccination or culling of susceptible individuals. Disease is characterized by pre- symptomatic phase which makes detection and control difficult. Three general strategies emerge, global preventive treatment, local treatment within a neighborhood of certain size and only palliative treatment with no prevention. The choice between the strategies depends on relative costs of palliative and preventive treatment. The details of the local strategy and in particular the size of the optimal treatment neighborhood weakly depends on disease infectivity but strongly depends on other epidemiological factors. The required extend of prevention is proportiona...

  11. Cooperative research for human factors review of advanced control rooms

    International Nuclear Information System (INIS)

    This project has been performed as cooperative research between KAERI and USNRC. Human factors issues related to soft controls, which is one of key features of advanced HSI, are identified in this project. The issues are analyzed for the evaluation approaches in either experimental or analytical ways. Also, issues requiring additional researches for the evaluation of advanced HSI are identified in the areas of advanced information systems design, computer-based procedure systems, soft controls, human systems interface and plant modernization process, and maintainability of digital systems. The issues are analyzed to discriminate the urgency of researches on it to high, medium, and low levels in consideration of advanced HSI development status in Korea, and some of the issues that can be handled by experimental researches are identified. Additionally, an experimental study is performed to compare operator's performance on human error detection in advanced control rooms vs. in conventional control rooms. It is found that advanced control rooms have several design characteristics hindering operator's error detection performance compared to conventional control rooms

  12. Shifts in Arctic phenology in response to climate and anthropogenic factors as detected from multiple satellite time series

    International Nuclear Information System (INIS)

    There is an urgent need to reduce the uncertainties in remotely sensed detection of phenological shifts of high latitude ecosystems in response to climate changes in past decades. In this study, vegetation phenology in western Arctic Russia (the Yamal Peninsula) was investigated by analyzing and comparing Normalized Difference Vegetation Index (NDVI) time series derived from the Advanced Very High Resolution Radiometer (AVHRR), the Moderate Resolution Imaging Spectroradiometer (MODIS), and SPOT-Vegetation (VGT) during the decade 2000–2010. The spatial patterns of key phenological parameters were highly heterogeneous along the latitudinal gradients based on multi-satellite data. There was earlier SOS (start of the growing season), later EOS (end of the growing season), longer LOS (length of the growing season), and greater MaxNDVI from north to south in the region. The results based on MODIS and VGT data showed similar trends in phenological changes from 2000 to 2010, while quite a different trend was found based on AVHRR data from 2000 to 2008. A significantly delayed EOS (p < 0.01), thus increasing the LOS, was found from AVHRR data, while no similar trends were detected from MODIS and VGT data. There were no obvious shifts in MaxNDVI during the last decade. MODIS and VGT data were considered to be preferred data for monitoring vegetation phenology in northern high latitudes. Temperature is still a key factor controlling spatial phenological gradients and variability, while anthropogenic factors (reindeer husbandry and resource exploitation) might explain the delayed SOS in southern Yamal. Continuous environmental damage could trigger a positive feedback to the delayed SOS. (letter)

  13. Variability of photosynthetic parameters of Pinus sibirica Du Tour needles under changing climatic factors

    Directory of Open Access Journals (Sweden)

    A.P. Zotikova

    2013-12-01

    Full Text Available The air temperature and relative humidity and the intensity of photosynthetically active radiation are the basic ecological factors determining geographical distribution of a species. Wood plant adaptation depends on the intensity of physiological and biochemicalprocesses of plants as a response to changing environmental factors. Investigations to reveal (detect the variability of modification andgenetic components of the photosynthetic parameters in needles of the Siberian cedar (Pinus sibirica Du Tour mountain ecotypes, distributed in central part of the Altai Mountains, were carried out. Also, the survey was extended to some experiments with these ecotypes introduced to mild climate and flat regions from south-western of Siberia. The length and thickness of needles, the size of chloroplasts, content of the photosynthetic pigments, and the functional activity of chloroplastsat the level of photo system II were the evaluated traits. Growing under mountainous conditions (at about 2000m elevation, the two-year-old needles were shorter and thicker and contained very large in size chloroplasts while the content of chlorophylls and carotinoids was twice lower than that in the local ecotype growing in the lowlands. On the other hand, more green and yellow pigments were found in needles of mountain ecotypes planted in the lowlands compared to the local lowland ectype trees. A decrease in pool of the photosynthetic pigments in the highlands ecotypes is probably due to decreased biosynthesis andincreased photo-destruction caused by severe light and temperature conditions. These parameters are likely to be associated withmodifications due to intense insolation, low temperature, ozone concentration, UV radiation, and other negative factors that are morepronounced at high elevation. Despite the large pool of accumulated photosynthetic pigments, the functional activity of chloroplasts in themountain ecotype at the level

  14. Climate change adaptation and the social factor; Klimatilpasning og den sociale faktor

    Energy Technology Data Exchange (ETDEWEB)

    Kjerulf Petersen, L.; Jensen, Anne; Svalgaard Nielsen, S.

    2009-06-15

    This report addresses the social aspects of climate change adaptation. How do people perceive and relate to climate change adaptation; what risks are associated with climate change, and how are these risks balanced with other risks and concerns of everyday life and long-range choices? The report is based on an explorative study about social aspects of climate change adaptation in Denmark. The issue was investigated through literature studies and interviews with respondents with residence in different parts of Denmark. The study was based on a distinction between climate change mitigation and adaptation and further on an assumption in adaptation policies that some adaptation measures - for economic or practical reasons - will have to be carried out by private citizens and households. This study showed, however, that the distinction between climate change mitigation and adaptation is of little significance for lay people. Moreover, the prospect of climate change does provoke reflections on social values and the need for saving energy, but when it comes to protecting ones own life and property against future damaging effects of climate change the threat seems distant and other forms of home improvement seem more relevant. Nevertheless, some adaptation measures are carried out by single households and local communities. When households experience weather related damages - of a kind that are expected to occur more frequently and with greater force as a result of climate changes - they take action to repair damages and prevent similar damages in the future; at least the kind of action that is easily carried out such as moving valuable goods from the basement or felling a tree. Such measures are, however, not necessarily understood in a context of climate change adaptation; they are rather specific reactions to acute problems. To the extent that a more thorough precautionary adaptation effort is required, also by private citizens, it will have to be performed in

  15. Parameter Estimation of Dynamic Multi-zone Models for Livestock Indoor Climate Control

    DEFF Research Database (Denmark)

    Wu, Zhuang; Stoustrup, Jakob; Heiselberg, Per

    2008-01-01

    In this paper, a multi-zone modeling concept is proposed based on a simplified energy balance formulation to provide a better prediction of the indoor horizontal temperature variation inside the livestock building. The developed mathematical models reflect the influences from the weather, the liv......In this paper, a multi-zone modeling concept is proposed based on a simplified energy balance formulation to provide a better prediction of the indoor horizontal temperature variation inside the livestock building. The developed mathematical models reflect the influences from the weather......, the livestock, the ventilation system and the building on the dynamic performance of indoor climate. Some significant parameters employed in the climate model as well as the airflow interaction between each conceptual zone are identified with the use of experimental time series data collected during spring...... and winter at a real scale livestock building in Denmark. The obtained comparative results between the measured data and the simulated output confirm that a very simple multi-zone model can capture the salient dynamical features of the climate dynamics which are needed for control purposes....

  16. Orbital control, climate seasonality, and landscape evolution in the Quaternary Rocky Mountains

    Science.gov (United States)

    Sewall, Jacob O.; Riihimaki, Catherine A.; Kadegis, Jeffrey

    2015-12-01

    While climate has long been implicated in the extensive erosion of Eocene through Miocene-aged basin fills in the Rocky Mountains, lack of precise, high temporal-density datasets of landform ages has made it difficult to detail the mechanisms by which climate increased relief. A dense dataset of (U-Th)/He dates from the Powder River Basin, Wyoming and Montana, USA, indicates correspondence between elevated exhumation and peaks in orbital eccentricity. Here we use an atmospheric general circulation model to investigate the potential role of eccentricity in enhancing erosion in the Rocky Mountains. We find that with high orbital eccentricity (0.05767), elevated seasonality (the moving vernal equinox of perihelion [MVELP] = 270°) results in 10-100% more summer precipitation and surface runoff than low seasonality (MVELP = 90°). Under low orbital eccentricity (0.0034), precipitation and runoff changes across a precession cycle are negligible. These results suggest that elevated eccentricity could, indeed, be associated with more intense summer precipitation and runoff, which could then drive higher landscape erosion rates. This finding could explain the occurrence of ~ 100-kyr cyclicity in Powder River Basin landform ages and provides a clear, non-glacial, link between climate variability and landscape evolution in the Rocky Mountains. In this, and other low-to-mid-latitude sedimentary basins, runoff volume and not glacier dynamics may be the variable that exerts primary control on landscape evolution.

  17. Based on Multi-Factors Grey Prediction Control for Elevator Velocity Modulation

    OpenAIRE

    Jiming Wang; Jin Ning; Ye Fei

    2012-01-01

    This paper uses the double-factors grey prediction and the fuzzy controller for the elevator car speed control. We introduce double-factors grey control to predict car vibration for elevator speed during the operation. Simulation results show that based on multi-factors gray prediction fuzzy PI control for elevator velocity modulation system closer than simple gray fuzzy PI control elevator speed control system to the actual operation. The control effect of double factors grey fuzzy PI contro...

  18. NREL Reveals Links Among Climate Control, Battery Life, and Electric Vehicle Range (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2012-06-01

    Researchers at the National Renewable Energy Laboratory (NREL) are providing new insights into the relationships between the climate-control systems of plug-in electric vehicles and the distances these vehicles can travel on a single charge. In particular, NREL research has determined that 'preconditioning' a vehicle-achieving a comfortable cabin temperature and preheating or precooling the battery while the vehicle is still plugged in-can extend its driving range and improve battery life over the long term.

  19. Health-care climate, perceived self-care competence, and glycemic control among patients with type 2 diabetes in primary care

    Directory of Open Access Journals (Sweden)

    Anne M Koponen

    2015-04-01

    Full Text Available This study showed, in line with self-determination theory, that glycemic control among patients with type 2 diabetes (n = 2866 was strongly associated with perceived self-care competence, which in turn was associated with autonomous motivation and autonomy-supportive health-care climate. These associations remained after adjusting for the effect of important life-context factors. Autonomous motivation partially mediated the effect of health-care climate on perceived competence, which fully mediated the effect of autonomous motivation on glycemic control. The results of the study emphasize health-care personnel’s important role in supporting patients’ autonomous motivation and perceived self-care competence.

  20. Climate controls in a historic house museum in the tropics : a case study of collection care and human comfort

    Energy Technology Data Exchange (ETDEWEB)

    Maekawa, S.; Beltran, V. [Getty Conservation Inst., Los Angeles, CA (United States); Carvalho, C. [Casa de Rui Barbosa Foundation, Rio de Janeiro (Brazil); Toledo, F. [Conservare, Recife (Brazil)

    2009-07-01

    This paper reported on a ventilation/dehumidification-based climate control strategy that was successfully used in a historic house museum in a hot and humid climate. The building envelope of the Casa de Rui Barbosa Museum in Rio de Janeiro, Brazil was repaired and original passive climate designs were restored. A ventilator and dehumidifier-based climate control system was installed in the basement and attic. The thermal comfort of occupants was addressed by using an air conditioning system with a high air exchange rate and ensuring high air movement along visitor pathways. Energy conservation measures were adopted whereby full ventilation was used during dry outside conditions and full recirculation and hibernation modes were used during non-visiting hours. The installed temperature control system has maintained the indoor temperature at about 25 degrees C with reduced air pollution levels and particulate matters. Visitors have expressed satisfaction regarding thermal comfort, air quality, daylighting and low noise levels. 6 refs., 7 figs.

  1. Effect of Climate Factors on the Childhood Pneumonia in Papua New Guinea: A Time-Series Analysis.

    Science.gov (United States)

    Kim, Jinseob; Kim, Jong-Hun; Cheong, Hae-Kwan; Kim, Ho; Honda, Yasushi; Ha, Mina; Hashizume, Masahiro; Kolam, Joel; Inape, Kasis

    2016-02-15

    This study aimed to assess the association between climate factors and the incidence of childhood pneumonia in Papua New Guinea quantitatively and to evaluate the variability of the effect size according to their geographic properties. The pneumonia incidence in children under five-year and meteorological factors were obtained from six areas, including monthly rainfall and the monthly average daily maximum temperatures during the period from 1997 to 2006 from national health surveillance data. A generalized linear model was applied to measure the effect size of local and regional climate factor. The pooled risk of pneumonia in children per every 10 mm increase of rainfall was 0.24% (95% confidence interval: -0.01%-0.50%), and risk per every 1 °C increase of the monthly mean of the maximum daily temperatures was 4.88% (95% CI: 1.57-8.30). Southern oscillation index and dipole mode index showed an overall negative effect on childhood pneumonia incidence, -0.57% and -4.30%, respectively, and the risk of pneumonia was higher in the dry season than in the rainy season (pooled effect: 12.08%). There was a variability in the relationship between climate factors and pneumonia which is assumed to reflect distribution of the determinants of and vulnerability to pneumonia in the community.

  2. Risk Factors For Ectopic Pregnancy : A Case Control Study

    Directory of Open Access Journals (Sweden)

    Deshmukh J.S

    1999-01-01

    Full Text Available Research question: Which are the risk factors for ectopic pregnancy . Objective: To study the strength of association between hypothesised risk factors and ectopic pregnancy. Study design: Unmatched case- control study. Setting: Government Medical College, Hospital, Nagpur. Participants: 133 cases of ectopic pregnancy and equal number of controls (non pregnant women admitted to study hospital. Study variables : Pelvic inflammatory diseases, sexually transmitted diseases, IUD use at conception , past use of IUD, prior ectopic pregnancy, OC pills use at the time of conception, past use of OC pills, induced abortion, spontaneous abortion, infertility and pelvic and abdominal surgery. Statistical analysis: Odds ratios & their 95% CI, Pearson’s chi square test, unconditional logistic regression analysis and population attributable risk proportion. Results : Use of IUD at conception, prior ectopic pregnancy , pelvic inflammatory disease, sexually transmitted diseases, infertility, OC pills use at the time of conception, past use of IUD and induced abortion were found to be significantly associated with ectopic pregnancy. Conclusion: Identification of these risk factors for etopic pregnancy shall help in early detection and appropriate management in an individual case and it may help in devising a comprehensive preventive strategy for ectopic pregnancy

  3. Autoregulatory systems controlling translation factor expression: Thermostat-like control of translational accuracy

    OpenAIRE

    Betney, Russell; de Silva, Eric; Krishnan, Jawahar; Stansfield, Ian

    2010-01-01

    In both prokaryotes and eukaryotes, the expression of a large number of genes is controlled by negative feedback, in some cases operating at the level of translation of the mRNA transcript. Of particular interest are those cases where the proteins concerned have cell-wide function in recognizing a particular codon or RNA sequence. Examples include the bacterial translation termination release factor RF2, initiation factor IF3, and eukaryote poly(A) binding protein. The regulatory loops that c...

  4. 寒热等气候因子相关基因与疾病%Some Genes of Climatic Factor in Cold and Heat Related to Disease Response

    Institute of Scientific and Technical Information of China (English)

    林乔; 王米渠; 张敬远

    2002-01-01

    The theory of evolutive phases and climatic changes in Canon be analyzed with the dataof gene related by comparative way. There are results as follows: A lot of endemic and epidemic diseasesunder the climatic changes will being induced with the relationship of HLA. There are observed by ancientdoctors that under the climatic factor of same year of sixty Ganzhi Code Years Cycle, there are induced asame diseases. If you are comparing with the symptoms of that diseases induced in a year and by someHLA genes, you can find that there be similar. Obviously, would you not recognize that there are no rela-tionship between certain climatic factor and HLA?

  5. An information value based analysis of physical and climatic factors affecting dengue fever and dengue haemorrhagic fever incidence

    Directory of Open Access Journals (Sweden)

    Tripathi Nitin

    2005-06-01

    Full Text Available Abstract Background Vector-borne diseases are the most dreaded worldwide health problems. Although many campaigns against it have been conducted, Dengue Fever (DF and Dengue Haemorrhagic Fever (DHF are still the major health problems of Thailand. The reported number of dengue incidences in 1998 for the Thailand was 129,954, of which Sukhothai province alone reported alarming number of 682. It was the second largest epidemic outbreak of dengue after 1987. Government arranges the remedial facilities as and when dengue is reported. But, the best way to control is to prevent it from happening. This will be possible only when knowledge about the relationship of DF/DHF with climatic and physio-environmental agents is discovered. This paper explores empirical relationship of climatic factors rainfall, temperature and humidity with the DF/DHF incidences using multivariate regression analysis. Also, a GIS based methodology is proposed in this paper to explore the influence of physio-environmental factors on dengue incidences. Remotely sensed data provided important data about physical environment and have been used for many vector borne diseases. Information Values (IV method was utilised to derive influence of various factors in the quantitative terms. Researchers have not applied this type of analysis for dengue earlier. Sukhothai province was selected for the case study as it had high number of dengue cases in 1998 and also due to its diverse physical setting with variety of land use/land cover types. Results Preliminary results demonstrated that physical factors derived from remotely sensed data could indicate variation in physical risk factors affecting DF/DHF. A composite analysis of these three factors with dengue incidences was carried out using multivariate regression analysis. Three empirical models ER-1, ER-2 and ER-3 were evaluated. It was found that these three factors have significant relation with DF/DHF incidences and can be related to

  6. Economic Model Predictive Control for Building Climate Control in a Smart Grid

    DEFF Research Database (Denmark)

    Halvgaard, Rasmus; Poulsen, Niels Kjølstad; Madsen, Henrik;

    2012-01-01

    to production is crucial. We present a model for a house with a heat pump used for supplying thermal energy to a floor heating system. The model is a linear state space model and the resulting controller is an Economic MPC formulated as a linear program. The model includes forecasts of both weather...

  7. Frequency control system based on power factor control of asynchronous motor

    Institute of Scientific and Technical Information of China (English)

    MENG Qing-chun; YANG Fei-xia; REN Zhi-ling

    2005-01-01

    Deduced the relationship between the power factor (PF) and the angular frequency according to the simplified equivalent circuit of asynchronous motor, forming a power factor auto-control system. An anti-interference circuit was also introduced in the middle voltage link of inverter to avoid the shift of the optimum PF point caused by the change of the load and the reliable run of the control system was assured. The experiment results show that it has a good self-adaptation in the whole scope of speed adjustment and an obvious economization on energy while it runs under load.

  8. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

    KAUST Repository

    Prest, Emmanuelle I.

    2016-02-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  9. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges.

    Science.gov (United States)

    Prest, Emmanuelle I; Hammes, Frederik; van Loosdrecht, Mark C M; Vrouwenvelder, Johannes S

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  10. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

    Science.gov (United States)

    Prest, Emmanuelle I.; Hammes, Frederik; van Loosdrecht, Mark C. M.; Vrouwenvelder, Johannes S.

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  11. Biological stability of drinking water: controlling factors, methods and challenges

    Directory of Open Access Journals (Sweden)

    Emmanuelle ePrest

    2016-02-01

    Full Text Available Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g. development of opportunistic pathogens, aesthetic (e.g. deterioration of taste, odour, colour or operational (e.g. fouling or biocorrosion of pipes problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors such as (i type and concentration of available organic and inorganic nutrients, (ii type and concentration of residual disinfectant, (iii presence of predators such as protozoa and invertebrates, (iv environmental conditions such as water temperature, and (v spatial location of microorganisms (bulk water, sediment or biofilm. Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i existing knowledge on biological stability controlling factors and (ii how these factors are affected by drinking water production and distribution conditions. In addition, (iii the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discuss how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order to

  12. Multiple Sclerosis Associated Risk Factors: A Case-Control Study

    Directory of Open Access Journals (Sweden)

    Jalal POOROLAJAL

    2015-11-01

    Full Text Available Background: Hamadan Province is one of the high-risk regions in Iran for Multiple sclerosis (MS. A majority of the epidemiological studies conducted in Iran addressing MS are descriptive. This study was conducted to assess MS and its associated risk factors in Hamadan Province, the west of Iran.Methods: This case-control study compared 100 patients with MS (case group and 100 patients with acute infectious diseases (control group from September 2013 to March 2014. A checklist was used to assess the demographic, medical, and family history of the patients. The Friedman-Rosenman questionnaire was also used to assess personality type. Statistical analysis was performed using logistic regression model with Stata 11 software program.Results: The adjusted odds ratio (OR estimate of MS was 4.37 (95% CI: 2.33, 8.20 for females compared to males; 0.15 (95% CI: 0.06, 0.43 for people aged above 50 years compared to aged 14 to 29 years; 0.44 (95% CI: 0.21, 0.91 for overweight or obese people compared to normal weights. Crude OR indicated a significant association between the occurrence of MS and exclusive breast feeding, season of birth, and smoking. However, the association was not statistically significant after adjustment for other covariates.Conclusion: The risk of MS is significantly lower in male gender, obese/overweight, and old people. Furthermore, non-smoking, non-exclusive breast-feeding, and born in autumn may increase the risk of MS but need further investigation. However, long-term large prospective cohort studies are needed to investigate the true effect of the potential risk factors on MS. Keywords: Multiple sclerosis, Risk factors, Case-control study, Iran

  13. Tectonic and climatic control on geomorphological and sedimentary evolution of the Mercure basin, southern Apennines, Italy

    Science.gov (United States)

    Robustelli, Gaetano; Ermolli, Elda Russo; Petrosino, Paola; Jicha, Brian; Sardella, Raffaele; Donato, Paola

    2014-06-01

    The morpho-tectonic and sedimentary evolution of the Mercure intramontane basin (Calabria-Lucania boundary, southern Apennines) has been assessed through facies analysis, morphostratigraphy and geomorphological correlation with adjacent areas. The Mercure basin, one of the most active seismogenic zones of the southern Apennines, is a favorable area for reconstructing the main stages of landscape evolution of the axial zone because of its capability to record changes in base level during the Quaternary. In addition, the presence of both erosional and depositional Palaeosurfaces is a useful marker for reconstructing tectonic and morphogenetic events, and hence to detect the role played by tectonics and climate in its genesis, evolution and extinction. The present study identifies the key role of tectonics and denudation, combined with high-frequency floods, as mechanisms controlling alluvial sedimentation in the study area. During endorheic conditions, denudational processes driven by pulses of extensional deformation of the basin margin caused strong alluvial inputs that resulted in the development of alluvial fans. Alluvial facies are mainly characterized by turbulent, subaerial, hyperconcentrated flood flows deposited during the glacial, semi-arid conditions of MIS 14. The retrogradational stacking pattern of the alluvial system indicates decreasing rates of tectonic activity along with declining river gradients. The Mercure coalescing alluvial fans were inundated by lake transgression during MIS 13 in response to (i) abrupt tectonic subsidence at the basin margins and (ii) large decrease of coarse sediment supply due to the interplay among climate, tectonics and catchment size changes. In this regard, it is suggested that tectonic control on the drainage network along with climate and long-term slope evolution may have caused marked pulses in sediment supply, thus influencing the arrangement of facies associations in the sedimentary succession. In addition, the

  14. Regional flood frequency analysis in Triveneto (Italy): climate and scale controls

    Science.gov (United States)

    Persiano, Simone; Castellarin, Attilio; Domeneghetti, Alessio; Brath, Armando

    2016-04-01

    The growing concern about the possible effects of climate change on flood frequency regime is leading Authorities to review previously proposed procedures for design-flood estimation, such as national regionalization approaches. Our study focuses on the Triveneto region, a broad geographical area in North-eastern Italy consisting of the administrative regions of Trentino-Alto Adige, Veneto and Friuli-Venezia Giulia. A reference procedure for design flood estimation in Triveneto is available from the Italian NCR research project "VA.PI.", which developed a regional model using annual maximum series (AMS) of peak discharges that were collected up to the 80s by the former Italian Hydrometeorological Service. We consider a very detailed AMS database that we recently compiled for ~80 catchments located in Triveneto. Our dataset includes the historical data mentioned above, together with more recent data obtained from Regional Services and annual maximum peak streamflows extracted from inflow series to artificial reservoirs and provided by dam managers. All ~80 study catchments are characterized in terms of several geomorphologic and climatic descriptors. The main objectives of our study are: (1) to check whether climatic and scale controls on flood frequency regime in Triveneto are similar to the controls that were recently found in Europe; (2) to verify the possible presence of trends as well as abrupt changes in the intensity and frequency of flood extremes by looking at changes in time of regional L-moments of annual maximum floods; (3) to assess the reliability and representativeness of the reference procedure for design flood estimation relative to flood data that were not included in the VA.PI. dataset (i.e. more recent data collected after the 80s and historical data provided by dam managers); (4) to develop an updated reference procedure for design flood estimation in Triveneto by using a focused-pooling approach (i.e. Region of Influence, RoI).

  15. Controlling harmful cyanobacterial blooms in a world experiencing anthropogenic and climatic-induced change.

    Science.gov (United States)

    Paerl, Hans W; Hall, Nathan S; Calandrino, Elizabeth S

    2011-04-15

    Harmful (toxic, food web altering, hypoxia generating) cyanobacterial algal blooms (CyanoHABs) are proliferating world-wide due to anthropogenic nutrient enrichment, and they represent a serious threat to the use and sustainability of our freshwater resources. Traditionally, phosphorus (P) input reductions have been prescribed to control CyanoHABs, because P limitation is widespread and some CyanoHABs can fix atmospheric nitrogen (N(2)) to satisfy their nitrogen (N) requirements. However, eutrophying systems are increasingly plagued with non N(2) fixing CyanoHABs that are N and P co-limited or even N limited. In many of these systems N loads are increasing faster than P loads. Therefore N and P input constraints are likely needed for long-term CyanoHAB control in such systems. Climatic changes, specifically warming, increased vertical stratification, salinization, and intensification of storms and droughts play additional, interactive roles in modulating CyanoHAB frequency, intensity, geographic distribution and duration. In addition to having to consider reductions in N and P inputs, water quality managers are in dire need of effective tools to break the synergy between nutrient loading and hydrologic regimes made more favorable for CyanoHABs by climate change. The more promising of these tools make affected waters less hospitable for CyanoHABs by 1) altering the hydrology to enhance vertical mixing and/or flushing and 2) decreasing nutrient fluxes from organic rich sediments by physically removing the sediments or capping sediments with clay. Effective future CyanoHAB management approaches must incorporate both N and P loading dynamics within the context of altered thermal and hydrologic regimes associated with climate change.

  16. Hospital safety climate, psychosocial risk factors and needlestick injuries in Japan.

    Science.gov (United States)

    Smith, Derek R; Muto, Takashi; Sairenchi, Toshimi; Ishikawa, Yumiko; Sayama, Shizue; Yoshida, Atsushi; Townley-Jones, Maureen

    2010-01-01

    To investigate the interactions between safety climate, psychosocial issues and Needlestick and Sharps Injuries (NSI), a cross-sectional study was undertaken among nurses at a university teaching hospital in Japan (89% response rate). NSI were correlated with various aspects of hospital safety climate including supporting one another at work, the protection of staff against blood-borne diseases being a high management priority, managers doing their part to protect staff from blood-borne disease, having unsafe work practices corrected by supervisors, having the opportunity to use safety equipment to protect against blood-borne disease exposures, having an uncluttered work area, and having minimal conflict within their department. In conclusion, this study has demonstrated the importance of hospital safety climate in Japanese health care practice, particularly its relationship with NSI. Although the provision of safer devices remains critical in preventing injuries, ensuring a positive safety climate will also be essential in meeting these important challenges for nurses' occupational health.

  17. Three controllable factors of steady operation of EGSB reactor

    Institute of Scientific and Technical Information of China (English)

    LI Hui-li; LU Bing-nan; LI Fang

    2008-01-01

    The bench- scale EGSB (expanded granular sludge bed) reactor was operated to study the effect of sludge loading rate, pH value and nutrient element on the operation of the EGSB reactor and the control rule of these factors. Continuous flow was used to treat synthetic wastewater containing dextrose and beer, and the temperature of reactor was controlled at mesophiles temperature (33 ℃). The experimental results demonstrated trolled by adding sodium bicarbonate, the proper additive quantity was 1000-1200 mg/L; the additive quantity wastewater with 400-5000 mg/L COD concentration. The COD removal efficiency was over 85%. The operation of the EGSB reactor was steady and the EGSB reactor had strong anti-shock load ability.

  18. Intrinsic Factors Influencing the Infection by Helminth Parasites in Horses under an Oceanic Climate Area (NW Spain)

    OpenAIRE

    I. Francisco; Arias, M.; Cortiñas, F. J.; R. Francisco; E. Mochales; Dacal, V.; J. L. Suárez; Uriarte, J.; Morrondo, P.; Sánchez-Andrade, R.; P. Díez-Baños; Paz-Silva, A.

    2009-01-01

    A coprological survey to determine the influence of some intrinsic factors (breed, age, and sex) on the infection by helminth parasites in equine livestock (n = 418) under an oceanic climate area (NW Spain) was conducted. Faecal samples were individually collected and analyzed by the coprological techniques. The main strongylid genera identified were Trichonema and Cyalocephalus spp (small strongyles) and Strongylus and Triodontophorus (large strongyles). The prevalence of gastrointestinal ne...

  19. Circulating Influenza Virus, Climatic Factors, and Acute Myocardial Infarction: A Time Series Study in England and Wales and Hong Kong

    OpenAIRE

    Warren-Gash, Charlotte; Bhaskaran, Krishnan; Hayward, Andrew; Leung, Gabriel M.; Lo, Su-Vui; Wong, Chit-Ming; Ellis, Joanna; Pebody, Richard; Smeeth, Liam; Cowling, Benjamin J.

    2011-01-01

    Background. Previous studies identifying associations between influenza and acute cardiac events may have been confounded by climatic factors. Differing seasonal patterns of influenza activity in Hong Kong and England and Wales provide a natural experiment to examine associations with myocardial infarction (MI) independent of cold weather effects. Methods. Weekly clinical and laboratory influenza surveillance data, environmental temperature and humidity data, and counts of MI-associated hospi...

  20. Climate Control Load Reduction Strategies for Electric Drive Vehicles in Cold Weather

    Energy Technology Data Exchange (ETDEWEB)

    Jeffers, Matthew A.; Chaney, Larry; Rugh, John P.

    2016-04-01

    When operated, the climate control system is the largest auxiliary load on a vehicle. This load has significant impact on fuel economy for conventional and hybrid vehicles, and it drastically reduces the driving range of all electric vehicles (EVs). Heating is even more detrimental to EV range than cooling because no engine waste heat is available. Reducing the thermal loads on the heating, ventilating, and air conditioning system will extend driving range and increase the market penetration of EVs. Researchers at the National Renewable Energy Laboratory have evaluated strategies for vehicle climate control load reduction with special attention toward grid connected electric vehicles. Outdoor vehicle thermal testing and computational modeling were used to assess potential strategies for improved thermal management and to evaluate the effectiveness of thermal load reduction technologies. A human physiology model was also used to evaluate the impact on occupant thermal comfort. Experimental evaluations of zonal heating strategies demonstrated a 5.5% to 28.5% reduction in cabin heating energy over a 20-minute warm-up. Vehicle simulations over various drive cycles show a 6.9% to 18.7% improvement in EV range over baseline heating using the most promising zonal heating strategy investigated. A national-level analysis was conducted to determine the overall national impact. If all vehicles used the best zonal strategy, the range would be improved by 7.1% over the baseline heating range. This is a 33% reduction in the range penalty for heating.

  1. Climate Control Load Reduction Strategies for Electric Drive Vehicles in Cold Weather: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Jeffers, Matthew; Chaney, Lawrence; Rugh, John

    2016-03-31

    When operated, the climate control system is the largest auxiliary load on a vehicle. This load has significant impact on fuel economy for conventional and hybrid vehicles, and it drastically reduces the driving range of all electric vehicles (EVs). Heating is even more detrimental to EV range than cooling because no engine waste heat is available. Reducing the thermal loads on the heating, ventilating, and air conditioning system will extend driving range and increase the market penetration of EVs. Researchers at the National Renewable Energy Laboratory have evaluated strategies for vehicle climate control load reduction with special attention toward grid connected electric vehicles. Outdoor vehicle thermal testing and computational modeling were used to assess potential strategies for improved thermal management and to evaluate the effectiveness of thermal load reduction technologies. A human physiology model was also used to evaluate the impact on occupant thermal comfort. Experimental evaluations of zonal heating strategies demonstrated a 5.5% to 28.5% reduction in cabin heating energy over a 20-minute warm-up. Vehicle simulations over various drive cycles show a 6.9% to 18.7% improvement in EV range over baseline heating using the most promising zonal heating strategy investigated. A national-level analysis was conducted to determine the overall national impact. If all vehicles used the best zonal strategy, the range would be improved by 7.1% over the baseline heating range. This is a 33% reduction in the range penalty for heating.

  2. Understanding disease control: influence of epidemiological and economic factors.

    Directory of Open Access Journals (Sweden)

    Katarzyna Oleś

    Full Text Available We present a model of disease transmission on a regular and small world network and compare different control options. Comparison is based on a total cost of epidemic, including cost of palliative treatment of ill individuals and preventive cost aimed at vaccination or culling of susceptible individuals. Disease is characterized by pre-symptomatic phase, which makes detection and control difficult. Three general strategies emerge: global preventive treatment, local treatment within a neighborhood of certain size and only palliative treatment with no prevention. While the choice between the strategies depends on a relative cost of palliative and preventive treatment, the details of the local strategy and, in particular, the size of the optimal treatment neighborhood depend on the epidemiological factors. The required extent of prevention is proportional to the size of the infection neighborhood, but depends on time till detection and time till treatment in a non-nonlinear (power law. The optimal size of control neighborhood is also highly sensitive to the relative cost, particularly for inefficient detection and control application. These results have important consequences for design of prevention strategies aiming at emerging diseases for which parameters are not nessecerly known in advance.

  3. Factors controlling phosphorus release from sediments in coastal archipelago areas.

    Science.gov (United States)

    Puttonen, Irma; Kohonen, Tuula; Mattila, Johanna

    2016-07-15

    In coastal archipelago areas of the northern Baltic Sea, significantly higher phosphate concentrations (6.0±4.5μmol/l, mean±SD) were measured in water samples close to the sediment surface compared with those from 1m above the seafloor (1.6±2.0μmol/l). The results indicated notable phosphate release from sediments under the bottom water oxygen concentrations of up to 250μmol/l, especially in areas that had experienced recent temporal fluctuation between oxic and hypoxic/anoxic conditions. No single factor alone was found to control the elevated PO4-P concentrations in the near-bottom water. In addition to the oxygen in the water, the contents of potentially mobile phosphorus fractions, grain-size, the organic content at the sediment surface, and the water depth were all important factors controlling the internal loading of phosphorus. The complexity of this process needs to be accounted for in assessments of the internal loading of phosphorus and in potential mitigation plans. PMID:27184132

  4. Assessment of five control strategies of an adjustable glazing at three different climate zones

    Directory of Open Access Journals (Sweden)

    Volker Ritter

    2015-11-01

    Full Text Available The energy demand for operating modern office spaces is often driven by either the annual heating demand, cooling demand or the demand for electrical lighting. The irradiation of the sun directly and indirectly affects the demand of all three. Consequently, the glazing of higher office buildings is often treated with coating that allows a fixed transmittance. Due to changing exterior conditions and interior needs, a fix-transmittance value is a compromise and most often doesn’t provide optimal thermal and visual conditions. The team in the research project named Fluidglass develops a new glazing in which the transmittance of the glazing can be adjusted. This is possible by colouring a fluid, which is circulated in chambers of the glazing. The concentration of the colorant can be infinitely adjusted. In addition, this window allows collecting heat in the exterior fluid and allows the interior fluid chamber to operate as heating panel. This paper presents a first assessment of different control strategies for adjusting the colorant concentration with a simplified model. The assessed control strategies result in considerably different overall energy demands. Certain control strategies have high potential for reducing the energy demand for heating and cooling depending on the locations (Munich 20–30% , Madrid 50–70% , Dubai 50–60%. However, certain control strategies increase the electricity demand for lighting, which needs to be considered in the further development. In general, control strategies that only consider the solar irradiation are less promising strategies in temperate climate than strategies that also take the interior temperature into account. The results of controls that also respect the thermal comfort based on a Predicted Mean Vote (PMV index can achieve low energy demand, presuming that a deviation from the highest level of comfort is acceptable. At this stage of research, none of the studied control strategies shows to be

  5. Dentine sensitivity risk factors: A case–control study

    Science.gov (United States)

    Mafla, Ana Cristina; Lopez-Moncayo, Luis Fernando

    2016-01-01

    Objective: To identify the clinical and psychological risk factors associated with dentine hypersensitivity (DH) in order to provide an early diagnosis and preventive therapy. Materials and Methods: A nested case–control study was design between 2011 and 2012. A total of 61 DH cases and 122 controls participated in this investigation. Cases and controls were matched for sex, group of age and socioeconomic status in a ratio of 1:2. DH to different stimuli such as cold, heat, acid, and sweet was asked in patient interviews, and dental examinations were used to detect DH. Clinical and psychological risk factors such as dental hygiene, periodontal disease, acid diet, alcohol consumption, psychological stress, and psychopathological symptoms were inquired. Psychological stress was measured through the PSS-10 and psychopathological symptoms were evaluated by SCL-90-R in Spanish. Descriptive and univariate binary logistic regression analysis were performed to estimate the association between clinical and psychological risk factors and the presence of DH. Results: Toothpaste abrasivity (odds ratio [OR] 1.881, 95% confidence interval [CI] 1.010–3.502, P = 0.045), gingival recession (OR 2.196, 95% CI 1.020–4.728, P = 0.041), and periodontal therapy (OR 5.357, 95% CI 2.051–13.993, P < 0.001) were associated with DH. Subjects with perceived stress (OR 1.211, 95%, CI 0.518–2.833, P = 0.658), obsessive-compulsive (OR 1.266, 95%, CI 0.494–3.240, P = 0.623) and hostility (OR 1.235, 95%, CI 0.507–3.007, P = 0.642) symptoms had a clinical greater odd of DH. Conclusion: Oral hygiene products and periodontal conditions are important risk factors for DH. Individuals with perceived stress, obsessive-compulsive, and hostility symptoms may increase a clinical risk for this entity. Targeting to dental counseling focused on oral hygiene products, periodontal therapy and a psychological evaluation may be promising in DH prevention. PMID:27011732

  6. The effect of family climate on risky driving of young novices: The moderating role of attitude and locus of control

    OpenAIRE

    Carpentier, Aline; BRIJS, Kris; Declercq, Katrien; Brijs, Tom; Daniels, Stijn; Wets, Geert

    2014-01-01

    The aim of the study was to examine the relative importance of young novice drivers’ family climate on their driving behavior. A sample of young novice drivers (N = 171) between the age of 17 and 24, who held their permanent (or temporary) driver's license for no longer than one year, participated. The questionnaire included items related to the participants’ family climate, 3 socio-cognitive determinants (i.e., attitude, locus of control and social norm), and risky driving behaviors. We expe...

  7. Risk factors for psoriasis: A case-control study.

    Science.gov (United States)

    Jankovic, Slavenka; Raznatovic, Milena; Marinkovic, Jelena; Jankovic, Janko; Maksimovic, Natasa

    2009-06-01

    A case-control study of 110 consecutive psoriatic outpatients and 200 unmatched controls was carried out in order to analyze the association of psoriasis with smoking habits, alcohol consumption, family history of psoriasis and stressful life events. Stressful life events were assessed with Paykel's Interview for Recent Life Events, a semi-structured interview covering 63 life events. According to our results, the risk of psoriasis is higher in urban dwellers (odds ratio [OR] = 3.61; 95% confidence interval [CI] = 0.99-13.18), patients who were divorced (OR = 5.69; 95% CI = 2.26-14.34) and those exposed to environmental tobacco smoke at home (OR = 2.29; 95% CI = 1.12-4.67). Alcohol consumption (OR = 2.55; 95% CI = 1.26-5.17), family history of psoriasis (OR = 33.96; 95% CI = 14.14-81.57) and change in work conditions (OR = 8.34; 95% CI = 1.86-37.43) are also risk factors for psoriasis. Separate analyses for men and women showed that the risk of developing psoriasis was stronger in men with a family history of psoriasis (OR = 30.39; 95% CI = 6.72-137.42) than in women (OR = 16.99; 95% CI = 7.21-40.07). The effect of environmental tobacco smoke at home was found only in women (OR = 2.44; 95% CI = 1.26-4.73). Future well-designed epidemiological studies need to be performed in order to determine whether lifestyle factors and stress could be risk factors triggering or aggravating psoriasis.

  8. Controllability analysis of transcriptional regulatory networks reveals circular control patterns among transcription factors

    DEFF Research Database (Denmark)

    Österlund, Tobias; Bordel, Sergio; Nielsen, Jens

    2015-01-01

    Transcriptional regulation is the most committed type of regulation in living cells where transcription factors (TFs) control the expression of their target genes and TF expression is controlled by other TFs forming complex transcriptional regulatory networks that can be highly interconnected. Here...... we analyze the topology and organization of nine transcriptional regulatory networks for E. coli, yeast, mouse and human, and we evaluate how the structure of these networks influences two of their key properties, namely controllability and stability. We calculate the controllability for each network...... as a measure of the organization and interconnectivity of the network. We find that the number of driver nodes n(D) needed to control the whole network is 64% of the TFs in the E. coli transcriptional regulatory network in contrast to only 17% for the yeast network, 4% for the mouse network and 8...

  9. Impacts of Climatic Factors on Runoff Coefficients in Source Regions of the Huanghe River

    Institute of Scientific and Technical Information of China (English)

    CHEN Liqun; LIU Changming; LI Yanping; WANG Guoqiang

    2007-01-01

    Runoff coefficients of the source regions of the Huanghe River in 1956-2000 were analyzed in this paper. In the 1990s runoff of Tangnaihai Hydrologic Station of the Huanghe River experienced a serious decrease, which had attracted considerable attention. Climate changes have important impact on the water resources availability. From the view of water cycling, runoff coefficients are important indexes of water resources in a particular catchment. Kalinin baseflow separation technique was improved based on the characteristics of precipitation and streamflow. After the separation of runoff coefficient (R/P), baseflow coefficient (Br/P) and direct runoff coefficient (Dr/P) were estimated. Statistic analyses were applied to assessing the impact of precipitation and temperature on runoff coefficients (including Dr/P,Br/P and R/P). The results show that in the source regions of the Huanghe River, mean annual baseflow coefficient was higher than mean annual direct runoff coefficient. Annual runoff coefficients were in direct proportion to annual precipitation and in inverse proportion to annual mean temperature. The decrease of runoff coefficients in the 1990s was closely related to the decrease in precipitation and increase in temperature in the same period. Over different sub-basins of the source regions of the Huanghe River, runoff coefficients responded differently to precipitation and temperature. In the area above Jimai Hydrologic Station where annual mean temperature is -3.9 ℃, temperature is the main factor influencing the runoff coefficients. Runoff coefficients were in inverse relation to temperature, and precipitation had nearly no impact on runoff coefficients. In subbasin between Jimai and Maqu Hydrologic Station Dr/P was mainly affected by precipitation while R/P and Br/P were both significantly influenced by precipitation and temperature. In the area between Maqu and Tangnaihai hydrologic stations all the three runoff coefficients increased with the rising

  10. Vegetation exerts a greater control on litter decomposition than climate warming in peatlands.

    Science.gov (United States)

    Ward, Susan E; Orwin, Kate H; Ostle, Nicholas J; Briones, J I; Thomson, Bruce C; Griffiths, Robert I; Oakley, Simon; Quirk, Helen; Bardget, Richard D

    2015-01-01

    Historically, slow decomposition rates have resulted in the accumulation of large amounts of carbon in northern peatlands. Both climate warming and vegetation change can alter rates of decomposition, and hence affect rates of atmospheric CO2 exchange, with consequences for climate change feedbacks. Although warming and vegetation change are happening concurrently, little is known about their relative and interactive effects on decomposition processes. To test the effects of warming and vegetation change on decomposition rates, we placed litter of three dominant species (Calluna vulgaris, Eriophorum vaginatum, Hypnum jutlandicum) into a peatland field experiment that combined warming.with plant functional group removals, and measured mass loss over two years. To identify potential mechanisms behind effects, we also measured nutrient cycling and soil biota. We found that plant functional group removals exerted a stronger control over short-term litter decomposition than did approximately 1 degrees C warming, and that the plant removal effect depended on litter species identity. Specifically, rates of litter decomposition were faster when shrubs were removed from the plant community, and these effects were strongest for graminoid and bryophyte litter. Plant functional group removals also had strong effects on soil biota and nutrient cycling associated with decomposition, whereby shrub removal had cascading effects on soil fungal community composition, increased enchytraeid abundance, and increased rates of N mineralization. Our findings demonstrate that, in addition to litter quality, changes in vegetation composition play a significant role in regulating short-term litter decomposition and belowground communities in peatland, and that these impacts can be greater than moderate warming effects. Our findings, albeit from a relatively short-term study, highlight the need to consider both vegetation change and its impacts below ground alongside climatic effects when

  11. Modelling climate control on cropland and grassland development using phenologically tuned variables

    DEFF Research Database (Denmark)

    Horion, Stéphanie Marie Anne F; Tychon, Bernard; Cornet, Yves

    2010-01-01

    that, between 1982 and 1999, primary productivity increased by 6% globally in response to climate change. This study also stressed the need to take into account the spatial variability of climatic constraints to plant growth when analyzing the climate change impact on vegetation. Others authors......Many studies already investigated the impact of climate change and climate variability on vegetation at global and continental scales. Using time series of remote sensing and climate data, Nemani et al. (2003) analyzed trends in Net Primary Production in relation with changes in climate and showed...... described different phenomenon linked with climate change such as increases of seasonal NDVI amplitude and growing season duration in the Northern high latitude or changes in circumpolar photosynthetic activities. Understanding the interactions between climate and vegetation is also a key issue in our Ph...

  12. Geohelminths distribution as affected by soil properties, physicochemical factors and climate in Sharkyia governorate Egypt.

    Science.gov (United States)

    Etewa, Samia E; Abdel-Rahman, Sara A; Abd El-Aal, Naglaa F; Fathy, Ghada M; El-Shafey, Mahmoud A; Ewis, A M G

    2016-06-01

    Soil-transmitted helminths are mainly a group of parasitic nematodes causing human infection through contact with parasite eggs or larvae; they survive in the warm and moist soil of the tropical and subtropical countries. This study was carried out in Sharkyia governorate from October, 2011 to October, 2013, to correlate between the prevalence and distribution of these parasites in the soil and the physicochemical factors affecting the examined samples of the soil. One hundred and twenty samples of different types of soil (clay, silt, sand) from different localities were collected and examined. Diagnosis of geohelminths was confirmed by the recovery of their eggs and larvae with other protozoa by different parasitological methods. The modified baermann method was found to be more efficient in detection of geohelminths larvae than charcoal culture method. Among the examined sites geohelminths were much more numerous in the soil of rural areas especially in the spring and summer seasons, while the contamination of canal banks by geohelminths was the worst (80 %). An insignificant correlation was reported between the soil texture and the number of positive samples in the examined areas while the relationship was directly proportional among (moisture, PH, organic). It appeared that the most common geohelminthic stage was Toxocara spp. eggs besides other types of protozoa especially Balantidium coli cysts. This suggests that factors other than soil texture are important in the prevalence of geohelminths in the soil e.g. temperature, moisture, PH and organic matter. So, to change some of these factors in a trial to control geoparasites transmission but with keeping the environment should be tried. These results also open the way to further studies to highlight the mutual affection between inhabitants of these sites and the prevalence of these geoparasites.

  13. Geohelminths distribution as affected by soil properties, physicochemical factors and climate in Sharkyia governorate Egypt.

    Science.gov (United States)

    Etewa, Samia E; Abdel-Rahman, Sara A; Abd El-Aal, Naglaa F; Fathy, Ghada M; El-Shafey, Mahmoud A; Ewis, A M G

    2016-06-01

    Soil-transmitted helminths are mainly a group of parasitic nematodes causing human infection through contact with parasite eggs or larvae; they survive in the warm and moist soil of the tropical and subtropical countries. This study was carried out in Sharkyia governorate from October, 2011 to October, 2013, to correlate between the prevalence and distribution of these parasites in the soil and the physicochemical factors affecting the examined samples of the soil. One hundred and twenty samples of different types of soil (clay, silt, sand) from different localities were collected and examined. Diagnosis of geohelminths was confirmed by the recovery of their eggs and larvae with other protozoa by different parasitological methods. The modified baermann method was found to be more efficient in detection of geohelminths larvae than charcoal culture method. Among the examined sites geohelminths were much more numerous in the soil of rural areas especially in the spring and summer seasons, while the contamination of canal banks by geohelminths was the worst (80 %). An insignificant correlation was reported between the soil texture and the number of positive samples in the examined areas while the relationship was directly proportional among (moisture, PH, organic). It appeared that the most common geohelminthic stage was Toxocara spp. eggs besides other types of protozoa especially Balantidium coli cysts. This suggests that factors other than soil texture are important in the prevalence of geohelminths in the soil e.g. temperature, moisture, PH and organic matter. So, to change some of these factors in a trial to control geoparasites transmission but with keeping the environment should be tried. These results also open the way to further studies to highlight the mutual affection between inhabitants of these sites and the prevalence of these geoparasites. PMID:27413327

  14. Climatic factors associated with reproductive performance in English Berkshire pigs and crossbred pigs between Landrace and Large White raised in a subtropical climate region of Japan.

    Science.gov (United States)

    Usui, Shiho; Koketsu, Yuzo

    2015-12-01

    Our objective was to characterize Berkshire female pigs associated with climatic factors by examining the interactions between two pig groups (pure English Berkshire females and crossbred females between Landrace and Large White) for reproductive performance in a humid subtropical zone. We analyzed 63,227 first-service records of 11,992 females in 12 herds. Climate data were obtained from four weather stations located close to the herds. Mean daily maximum temperatures (Tmax) and daily average relative humidity (ARH) for different time periods around servicing and farrowing of each female were coordinated with that female's reproductive performance data. Multilevel mixed-effects models were applied to the data. There were two-way interactions between the pig groups and either Tmax or ARH for weaning-to-first-mating interval (WMI) and number of total pigs born (TPB; P TPB decreased by 0.3 pigs as Tmax increased from 20 to 30 °C (P < 0.05), whereas that in crossbred females decreased by 0.4 pigs (P < 0.05). Therefore, we recommend producers apply advanced cooling systems for Berkshire females. PMID:26250151

  15. Simulation of thermal indoor climate in buildings by using human Projected Area Factors

    DEFF Research Database (Denmark)

    Christensen, Jørgen Erik

    2009-01-01

    measure for thermal environ-ment. The operative temperature is a function of the air temperature, the mean radiant temperature and the relative air velocity. However, in many programs for calculation of energy consumption and thermal indoor climate the model for calculating the mean radiant temperature......Nowadays many new and old buildings in Denmark have large glass surfaces. This is a consequence of the technical development of windows with low U-values that has made it possible to build houses with windows from floor to ceiling in northern climates. On the other hand if one is sitting close...... to these large windows on a cold winter day it is recognized that this can cause thermal discomfort. The calculation of this discomfort needs to be taken properly into account in the simulation of the thermal indoor climate and energy consumption of the rooms. The operative temperature can be used as a simple...

  16. Air pollution control and decreasing new particle formation lead to strong climate warming

    Directory of Open Access Journals (Sweden)

    R. Makkonen

    2012-02-01

    Full Text Available The number concentration of cloud droplets determines several climatically relevant cloud properties. A major cause for the high uncertainty in the indirect aerosol forcing is the availability of cloud condensation nuclei (CCN, which in turn is highly sensitive to atmospheric new particle formation. Here we present the effect of new particle formation on anthropogenic aerosol forcing in present-day (year 2000 and future (year 2100 conditions. The present-day total aerosol forcing is increased from −1.0 W m−2 to −1.6 W m−2 when nucleation is introduced into the model. Nucleation doubles the change in aerosol forcing between years 2000 and 2100, from +0.6 W m−2 to +1.4 W m−2. Two climate feedbacks are studied, resulting in additional negative forcings of −0.1 W m−2 (+10% DMS emissions in year 2100 and −0.5 W m−2 (+50% BVOC emissions in year 2100. With the total aerosol forcing diminishing in response to air pollution control measures taking effect, warming from increased greenhouse gas concentrations can potentially increase at a very rapid rate.

  17. Climate change as a confounding factor in reversibility of acidification: RAIN and CLIMEX projects

    OpenAIRE

    R. F. Wright; Jenkins, A.

    2001-01-01

    International audience The RAIN and CLIMEX experiments at Risdalsheia, southernmost Norway, together cover 17 years (1984-2000) of whole-catchment manipulation of acid deposition and climate. A 1200 m2 roof placed over the forest canopy at KIM catchment excluded about 80% of ambient acid deposition; clean rain was sprinkled under the roof. A climate change treatment (3.7°C increase in air temperature and increase in air carbon dioxide concentrations to 560 ppmv) was superimposed on the cle...

  18. Climate change as a confounding factor in reversibility of acidification: RAIN and CLIMEX projects

    OpenAIRE

    R. F. Wright; Jenkins, A.

    2001-01-01

    The RAIN and CLIMEX experiments at Risdalsheia, southernmost Norway, together cover 17 years (1984-2000) of whole-catchment manipulation of acid deposition and climate. A 1200 m2 roof placed over the forest canopy at KIM catchment excluded about 80% of ambient acid deposition; clean rain was sprinkled under the roof. A climate change treatment (3.7°C increase in air temperature and increase in air carbon dioxide concentrations to 560 ppmv) was superimposed on the clean rain treatment for...

  19. Changes in Climatic Factors Influencing the Growth Period of Corn in Fengjie County

    Institute of Scientific and Technical Information of China (English)

    Xiaozhen; MAO; Xinli; MOU; Chen; MA; Jiang; HUANG; Lin; YUAN

    2014-01-01

    Under the background of global climate change,we analyze the change tendency of average temperature and amount of precipitation influencing the corn’s growth period. The results show that from March to August,the monthly temperatures show an upward trend,but the rise is different in different months,and the maximum temperature rise is in May. Precipitation in different months has different trends. Climate change brings about favorable conditions at high altitudes in Fengjie,reduces production due to the temperature drop after the beginning of autumn,and increases the pressure on the corn supply.

  20. Characteristics of climatic trends and correlation between pan-evaporation and environmental factors in the last 40 years over China

    Institute of Scientific and Technical Information of China (English)

    ZUO Hongchao; LI Dongliang; HU Yinqiao; BAO Yan; L(U) Shihua

    2005-01-01

    Using the data observed by 62 Chinese Routine Meteorological Stations (CRMS) with long term radiation observation, the climatic trends and the relationship between pan-evaporation and its environmental factors are analyzed comprehensively. The results show that during the last 40 years, the relative humidity is uptrend in west China, downtrend in east China, and their extrema are 0.20%/a and -0.22%/a respectively; the precipitations of about 61% CRMS keep uptrend, its maximum can reach 10.52 mm/a2 while the cloud amounts of about 79% CRMS keep downtrend slightly. About 98% CRMS display the air temperature uptrend, and the maximum is 0.11℃/a. About 76% CRMS display the land surface temperature uptrend. About 87% CRMS show the daily range of temperature downtrend. The global radiations observed by about 85% CRMS and the 10 m wind speeds observed by about 77% CRMS hold downtrend. The annual pan-evaporations of about 66% CRMS hold descend trend, and the biggest descent reaches -24.9 mm/a2. The pan-evaporation has good relationship with many environmental factors, but the relationship with the relative humidity is the best. All of the climatic trends respond to the global climate changes.

  1. TECTONIC AND CLIMATIC CONTROL ON DEPOSITION OF SEEP-CARBONATES: THE CASE OF MIDDLE-LATE MIOCENE SALSOMAGGIORE RIDGE (NORTHERN APENNINES, ITALY

    Directory of Open Access Journals (Sweden)

    ANDREA ARTONI

    2014-11-01

    Full Text Available Seep-carbonates are generally related to hydrocarbon seepage on continental margins. Modern cold seeps are abundant in actively deforming tectonic settings, suggesting that tectonics is one of the major controlling factor on fluid emissions. Hydrocarbon seepages areconsidered major geological sources of atmospheric methane, one of the most important green-house gases, and have also been related to climate changes. However, the interplaybetween tectonics and climate change in forcing seepage is not clearly understood. Miocene seep-carbonates, formed in a collisional settingsuch as that ofthe Salsomaggiore area of the Northern Apennines(Italy, provide an opportunitytoassess accumulation and release of methane in response to tectonics and climate change along a convergent margin. Thestudiedseep-carbonatesarerelated to fluid emissions of various intensities coeval with tectonic pulses.Newplanktonic foraminiferal biostratigraphic datareveals thatdepositionof these seep-carbonatesislate Serravallian-early Tortonian in age and partiallycoeval with the Miller’s global cooling event Mi 5 (as used below. These seep-carbonates were deposited in two stages with different seepage modes. During the first stage, local tectonic pulses at the onset of the Mi5 event may have producedslow seepage, whereas during the second stage regional tectonics and more extreme climatic conditions (coolest peak of Mi5 event may have resulted inafast and more intense seepage as suggested by increasing occurrence of chaotic facies. In the Salsomaggiore Ridge, tectonics and the Mi5 cooling event actively concurredtothe deposition of seep-carbonates in both stages.

  2. Processes and controlling factors of polygenetic dolomite formation in the Transdanubian Range, Hungary: a synopsis

    Science.gov (United States)

    Haas, János; Hips, Kinga; Budai, Tamás; Győri, Orsolya; Lukoczki, Georgina; Kele, Sándor; Demény, Attila; Poros, Zsófia

    2016-06-01

    In the Transdanubian Range (Hungary), dolostone and dolomitic limestone appear in a number of sedimentary successions formed from the Late Permian to the Late Triassic in various depositional settings and under various diagenetic conditions, whereas only a negligible amount of dolomite was detected in the post-Triassic formations. Seven dolomite-bearing units representing ramp, small and large carbonate platforms, and intraplatform basin settings are presented in this synopsis. In most cases, multi-stage and polygenetic dolomitization was inferred. The main mass of the dolostones was formed via near-surface diagenetic processes, which were commonly preceded by the formation of synsedimentary dolomite. Accordingly, surficial conditions that prevailed during sediment deposition controlled the dolomite-forming processes and thus the lateral extension and the time span of dolomitization. The area of episodic subaerial exposure was a critical controlling factor of the lateral extension of the near-surface dolomite genesis, whereas its temporal extension was mostly governed by climate. Burial diagenesis usually resulted in only moderate dolomitization, either in connection with compactional fluid flow or via thermal convection. The Triassic fault zones provided conduits for fluid flow that led to both replacive dolomitization and dolomite cement precipitation. In the Late Triassic extensional basins, synsedimentary fault-controlled dolomitization of basinal deposits was reconstructed.

  3. Phase detector for three-phase power factor controller

    Science.gov (United States)

    Nola, F. J. (Inventor)

    1984-01-01

    A phase detector for the three phase power factor controller (PFC) is described. The phase detector for each phase includes an operational amplifier which senses the current phase angle for that phase by sensing the voltage across the phase thyristor. Common mode rejection is achieved by providing positive feedback between the input and output of the voltage sensing operational amplifier. this feedback preferably comprises a resistor connected between the output and input of the operational amplifier. The novelty of the invention resides in providing positive feedback such that switching of the operational amplifier is synchronized with switching of the voltage across the thyristor. The invention provides a solution to problems associated with high common mode voltage and enables use of lower cost components than would be required by other approaches.

  4. Study of factors controlling organic pollution in Lake Kiba

    International Nuclear Information System (INIS)

    Lake Kiba is located in Ishikawa Prefecture and has been facing to high COD value, a simple indicator of organic pollution, of lake water. This study analyzed organic matter content in a sediment core with time scale and discussed factors controlling COD value. Sedimentation rate estimated from depth profile of 210Pbex is divided into three periods such as present-1989, 1989-1959 and 1959-past. TOC flux at the present is five times higher than that of 1959. The TOC/TN molar ratio decreased from 15.7 to 12.8. These results suggest that accumulation of total organic matter increases but the contribution of terrestrial organic matter and phytoplankton relatively varies with time. (author)

  5. Factors Influencing Glycemic Control in Children with Type 1 Diabetes

    Directory of Open Access Journals (Sweden)

    Seher Çakır

    2010-05-01

    Full Text Available Introduction: There are a plenty of factors influencing glycemic control in children with type 1 diabetes mellitus (DM. The aim of this study was to determine the factors influencing metabolic control in children with type 1 DM. Materials and Method: The study was performed in 200 children with type 1 DM between the ages 6 months to 18 years. This study was conducted by interviewing individually with the children and their families and completing the questionnaires related to their demographic features and data associated with their illness. The laboratory findings and medical information of the patients from the charts were also retrospectively recorded. Results: There were a total of 200 patients including 104 (52% girls and 96 (48% boys. The mean age of the patients was 11.7 (±4.26 years. The mean duration of diabetes was 3.8 years (6 months to 14 years. Eighty-nine percent of all patients and all of the patients between 12 and 18 years of age were on intensive insulin therapy. Mean insulin dose was 0.84±0.19 units/kg/day. The mean HbA1c value was 8.8%. Body mass index (BMI mean z-score was -0.06±1.19. There were no correlations between HbA1c and the duration of diabetes or age although a positive correlation was found with insulin dose (r=0.27 p<0.01. It was found that intensive therapy did not lower HbA1c values or the risk of severe hypoglycemia. Nevertheless, there was a decrease in HbA1c values of 72 (36% patients whose therapy was converted from conventional therapy to intensive therapy (p<0.05. HbA1c values were found to be higher in patients who lived with more than 4 persons in the house, who were non-compliant to follow-up or diet, who had more than 3 symptomatic hypoglycemia in the last 6 months, who had episodes of diabetic ketoacidosis (DKA, who were adolescent at the time of diagnosis, and who were admitted with diabetic ketoacidosis at the time of diagnosis (p<0.05. Although there was a correlation between insulin doses and

  6. Changes in forcing factors affecting coastal and shallow water erosion in the future Arctic climate change projections.

    Science.gov (United States)

    Dobrynin, Mikhail; Razumov, Sergey; Brovkin, Victor; Ilyina, Tatiana; Grigoriev, Mikhail

    2016-04-01

    Driving factors of seabed and coastal erosion in the Arctic can be classified as thermal and mechanical. Thermal factors such as air and ocean temperatures affect the seabed and coastal ground temperatures. Mechanical factors such as ocean currents and surface gravity waves contribute to the seabed and costal erosion due to shear stress. Due to polar amplification, the Arctic experiences strong increase in air and water temperature, sea-ice loss and changes in the ocean and atmospheric circulation, temperature and wind distribution. These climatic changes lead to changes in factors driving seabed and coastal erosion, which is expected to accelerate in the shallow Arctic regions such as the Laptev sea and East Siberian sea. In these regions, the coastal line to a large extent consists of frozen rocks, sediments and organic soils including ground ice. The increase of erosion rate of the coastal line will increase the release of organic and inorganic matter from thawed permafrost. Dynamics of thermal and mechanical drivers of seabed and coastal erosion in the present and future climate change (RCP8.5 scenario) simulated by the CMIP5 version of the MPI Earth system model and wave model WAM will be presented. Special attention will be given to changes in the air temperature, wind dynamics and development of new waves system in the ``ice-free'' Arctic and its role in the seabed and coastal erosion.

  7. Climatic factors directly impact the volatile organic compound fingerprint in green Arabica coffee bean as well as coffee beverage quality.

    Science.gov (United States)

    Bertrand, B; Boulanger, R; Dussert, S; Ribeyre, F; Berthiot, L; Descroix, F; Joët, T

    2012-12-15

    Coffee grown at high elevations fetches a better price than that grown in lowland regions. This study was aimed at determining whether climatic conditions during bean development affected sensory perception of the coffee beverage and combinations of volatile compounds in green coffee. Green coffee samples from 16 plots representative of the broad range of climatic variations in Réunion Island were compared by sensory analysis. Volatiles were extracted by solid phase micro-extraction and the volatile compounds were analysed by GC-MS. The results revealed that, among the climatic factors, the mean air temperature during seed development greatly influenced the sensory profile. Positive quality attributes such as acidity, fruity character and flavour quality were correlated and typical of coffees produced at cool climates. Two volatile compounds (ethanal and acetone) were identified as indicators of these cool temperatures. Among detected volatiles, most of the alcohols, aldehydes, hydrocarbons and ketones appeared to be positively linked to elevated temperatures and high solar radiation, while the sensory profiles displayed major defects (i.e. green, earthy flavour). Two alcohols (butan-1,3-diol and butan-2,3-diol) were closely correlated with a reduction in aromatic quality, acidity and an increase in earthy and green flavours. We assumed that high temperatures induce accumulation of these compounds in green coffee, and would be detected as off-flavours, even after roasting. Climate change, which generally involves a substantial increase in average temperatures in mountainous tropical regions, could be expected to have a negative impact on coffee quality. PMID:22980845

  8. Air pollution control and decreasing new particle formation lead to strong climate warming

    Directory of Open Access Journals (Sweden)

    R. Makkonen

    2011-09-01

    Full Text Available The number of cloud droplets determines several climatically relevant cloud properties. A major cause for the high uncertainty in the indirect aerosol forcing is the availability of cloud condensation nuclei (CCN, which in turn is highly sensitive to atmospheric new particle formation. Here we present the effect of new particle formation on anthropogenic aerosol forcing in present-day (year 2000 and future (year 2100 conditions. The total aerosol forcing (−1.61 W m−2 in year 2000 is simulated to be greatly reduced in the future, to −0.23 W m−2, mainly due to decrease in SO2 emissions and resulting decrease in new particle formation. With the total aerosol forcing decreasing in response to air pollution control measures taking effect, warming from increased greenhouse gas concentrations can potentially increase at a very rapid rate.

  9. Climatic Controls of Soil Carbon Cycling Across a Gradient of Sonoran Desert Ecosystems

    Science.gov (United States)

    Rasmussen, C.

    2009-04-01

    Arid and semiarid lands cover roughly 36% to 40% of global land area, highlighting the importance these ecosystems play in the global carbon cycle. The controls of arid and semiarid ecosystem carbon cycle processes, such as soil organic matter turnover and mineral weathering, remain poorly understood. To address this knowledge gap, we established a set of long-term soil monitoring sites across a gradient of semiarid ecosystems in the Sonoran Desert of the Southwestern USA. These sites were established as part of the Critical Zone Exploration Network (CZEN), sponsored by the US National Science Foundation. The primary objectives of the Sonoran Desert Environmental Gradient (SDEG) include: (i) characterizing climate forcing controls of soil physical, chemical and biological processes, and the flux of chemical species from soils to surface waters; and (ii) developing predictive models of carbon cycle response to climate and climate change. Particular attention is given to the bimodal precipitation regime characteristic of the SDEG ecosystems and the relative impact of warm versus cold precipitation on biogeochemical processes. The SDEG spans a steep elevation and environmental gradient on granitic parent materials near Tucson, Arizona, USA. Elevation ranges from 800-2650 m a.s.l. with concurrent shifts in climatic regime. Specifically, mean annual air temperature decreases (20-10 °C) and mean annual precipitation increases (30-85 cm) with elevation, with concomitant changes in vegetation from mixed desert-scrub (forest (>2000 m). We sampled soil and regolith material from each of vegetation community across the SDEG and established a long-term soil-moisture and temperature monitoring network. Pedon physicochemical data, coupled with elemental mass balance, radiocarbon analyses of soil organic matter, and terrestrial cosmogenic nuclide (10Be) analyses indicate substantial variation in carbon cycling across the SDEG. Soil morphology suggests the dominant pedogenic

  10. Climatic Controls on Spring Onset of the Tibetan Plateau Grasslands from 1982 to 2008

    Directory of Open Access Journals (Sweden)

    Wenjiang Zhang

    2015-12-01

    Full Text Available Understanding environmental controls on vegetation spring onset (SO in the Tibetan Plateau (TP is crucial to diagnosing regional ecosystem responses to climate change. We investigated environmental controls on the SO of the TP grasslands using satellite vegetation index (VI from the 3rd Global Inventory Modeling and Mapping Studies (GIMMS3g product, with in situ air temperature (Ta and precipitation (Prcp measurement records from 1982 to 2008. The SO was determined using a dynamic threshold method based on a 25% threshold of seasonal VI amplitude. We find that SO shows overall close associations with spring Ta, but is also subject to regulation from spring precipitation. In relatively dry but increasingly wetting (0.50 mm·year−1, p < 0.10 grasslands (mean spring Prcp = 22.8 mm; Ta = −3.27 °C, more precipitation tends to advance SO (−0.146 day·mm−1, p = 0.150 before the mid-1990s, but delays SO (0.110 day·mm−1, p = 0.108 over the latter record attributed to lower solar radiation and cooler temperatures associated with Prcp increases in recent years. In contrast, in relatively humid TP grasslands (73.0 mm; −3.51 °C, more precipitation delays SO (0.036 day·mm−1, p = 0.165 despite regional warming (0.045 °C·year−1, p < 0.05; the SO also shows a delaying response to a standardized drought index (mean R = 0.266, indicating a low energy constraint to vegetation onset. Our results highlight the importance of surface moisture status in regulating the phenological response of alpine grasslands to climate warming.

  11. Coastal erosion's influencing factors include development, dams, wells, and climate change

    International Nuclear Information System (INIS)

    The demographic flight to the coast, begun in early civilization, continues unabated worldwide according to latest studies. The percentage of population living on the coast is expected to remain relatively constant over the next few decades, but the total numbers will increase as the population increases. Recent coastal battering by hurricanes and extratropical storms poses questions about coastal habitability and the real economics of coastal development. Repair costs are borne by private individuals as well as the public in various direct and indirect ways. As these costs escalate, it is fitting to ask what the future portends for storm and coastal-flood damage. It is known that development pressures will continue to increase along the coast, but what will happen concurrently to natural-hazard threats to this infrastructure? Though much emphasis has been placed on sea-level rise, the broader issue is climate change in general. Here, the author considers climate change in both its natural and anthropogenic perspectives. Without becoming mired in the debate about the greenhouse effect and human influence on climatic shifts, some of the broad classes of natural hazards that might accompany climate change are examined. There are several categories of possible global-change effects on coastal erosion. In the early 1980's, an Environmental Protection Agency (EPA) report postulated increases in global sea level up to 4 meters during the next 100 years. Though balanced somewhat by other, lower estimates of sea-level rise, this higher extreme grabbed public attention. During the next decade, scientists attempted to concur on a more reasonable estimate of global sea-level rise due to climate change. Recent credible estimates suggest that approximately 10 to 20 percent of EPA's earlier maximum estimate is most reasonable

  12. Baseline for Climate Change: Modeling Watershed Aquatic Biodiversity Relative to Environmental and Anthropogenic Factors

    Energy Technology Data Exchange (ETDEWEB)

    Maurakis, Eugene G

    2010-10-01

    Objectives of the two-year study were to (1) establish baselines for fish and macroinvertebrate community structures in two mid-Atlantic lower Piedmont watersheds (Quantico Creek, a pristine forest watershed; and Cameron Run, an urban watershed, Virginia) that can be used to monitor changes relative to the impacts related to climate change in the future; (2) create mathematical expressions to model fish species richness and diversity, and macroinvertebrate taxa and macroinvertebrate functional feeding group taxa richness and diversity that can serve as a baseline for future comparisons in these and other watersheds in the mid-Atlantic region; and (3) heighten people’s awareness, knowledge and understanding of climate change and impacts on watersheds in a laboratory experience and interactive exhibits, through internship opportunities for undergraduate and graduate students, a week-long teacher workshop, and a website about climate change and watersheds. Mathematical expressions modeled fish and macroinvertebrate richness and diversity accurately well during most of the six thermal seasons where sample sizes were robust. Additionally, hydrologic models provide the basis for estimating flows under varying meteorological conditions and landscape changes. Continuations of long-term studies are requisite for accurately teasing local human influences (e.g. urbanization and watershed alteration) from global anthropogenic impacts (e.g. climate change) on watersheds. Effective and skillful translations (e.g. annual potential exposure of 750,000 people to our inquiry-based laboratory activities and interactive exhibits in Virginia) of results of scientific investigations are valuable ways of communicating information to the general public to enhance their understanding of climate change and its effects in watersheds.

  13. Impact of climatic factors on energy consumption during the heating season

    Science.gov (United States)

    Ginzburg, A. S.; Reshetar, O. A.; Belova, I. N.

    2016-09-01

    Global and regional climate changes produce a significant effect on energy production and consumption, especially on heating and air conditioning in residential, industrial, commercial, and office rooms. In Russia, with its contracting climate conditions, energy consumption varies a lot in different regions. Thus, we have to review the dynamics of energy consumption during the cold season individually for each region of the country. We analyzed the dynamics of duration and temperature of the heating season in Moscow region and completed a comparative study of heat energy consumption, actual and calculated based on the 'degreedays' concept, in the municipal economy of Moscow during the last decade. Based on the actual data analysis, we proved that conservation of energy resources in a large city relies not so much on a shortening of the heating period as on the growth of atmospheric air temperature in winter. The projected climate warming in the Moscow region in the nearest decades, along with measures of energy conservation, will promote a significant reduction in energy consumption of the municipal economy in winter. The results shown in this article were obtained in the process of preparing and implementing project no. 16-17-00114 by the Russian Science Foundation "Analysis of an impact of the regional climate change on the residential and commercial energy consumption of Russian megacities," within the main area of focus of the Russian Science Foundation, which is "Fundamental Research and Exploration in Main Topical Areas of Focus." The project was implemented within the framework of the scientific area of focus, which is "Reduction of the Risk and Mitigation of Consequences of Natural and Man-made Disasters" ("Studying Economical, Political, and Social Consequences of Global Climate Changes" problem).

  14. Risk factors in pediatric asthmatic patients. Cases and control studies.

    Directory of Open Access Journals (Sweden)

    Rafael Alejandro Gómez Baute

    2003-04-01

    Full Text Available Background: Asthma constitutes the first disease among chronic diseases in children. The morbid-mortality promoted to continue being elevated in spite of the new therapies. For this reason it is a disease with high priority for investigation in pediatric ages. Method: A control and case group study was carried out. The samples was composed by 72 asthmatic children from three General Comprehensive doctor offices from Palmira health area located in Cienfuegos Province, Cuba; and a control group of 72 children apparently healthy from the same population. A questionnaire with the different risk variables was elaborated. Odds ratio technique was used to estimate the risk. Results: low weight at birth, family history of asthma, brochiolitis antecedent and the excessive usage of antibiotics in children under 1 year old were the main risks found. Conclusions: It is conclusive that the exposure to home allergen plus a genetic favorable factor, the prematurity, and brochiolitis constituted the most outstanding elements to suffer from asthma in the population studied.

  15. Climate Versus Local Cave Environment Controls on Trace Element and Stable Isotopic Cycles in Annual Laminae in Speleothem

    Science.gov (United States)

    Mattey, D.; Grassineau, N. V.; Muller, W.; Garcia-Anton, E.; Fairchild, I. J.

    2011-12-01

    in Mg, Sr and soil derived elements P and Y but strong periodicity in δ13C that is largely decoupled from δ18O. Calcite precipitation at NSM. modulated by ventilation-controlled cave air pCO2, shows strong coupling of fabric, trace elements and stable isotopes. Laminae developed at the temperate maritime sites MA and HP have exceptionally well developed annual cycles in Mg, Sr and soil derived elements, P, Y and Zn but variations in δ13C and δ18O vary independently of seasonal change. Mg and Sr seem to be elements that can be strongly dominated by local processes such as prior calcite precipitation and ventilation controlled growth kinetics whereas elements P, Y or Zn, mobilized as organometallic complexes, have closer relations to soil processes and local climate. δ13C is sensitive to a range of factors but may closely track trace element cycles at sites where seasonal changes in cave air pCO2 are important; in general, evidence suggests that δ18O tracks seasonal or interannual variations in the δ18O of effective recharge but absence of a correlation between δ18O with δ13C does not always preclude some modification of δ18O by local processes.

  16. Analysis on the Climatic Change Characteristics of the Snow Cover Days and Its Influence Factors in Suzhou during Recent 50 Years

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The research aimed to study climatic variation characteristics of snow cover days and its influence factors in Suzhou of Anhui Province during recent 50 years. [Method] According to annual snow cover days and correlated data in Suzhou during 1961-2010, by using linear trend method, accumulative anomaly and complete correlation coefficient method, etc., the climatic variation characteristics of snow cover days and its influence factors in Suzhou were analyzed. [Result] In recent 50 years, the sno...

  17. Flood history of the Bavarian Alpine Foreland since the late Middle Ages in the context of internal and external climate forcing factors

    Directory of Open Access Journals (Sweden)

    O. Böhm

    2014-07-01

    1615–1665, 1730–1780, 1820–1870, and 1910–1955 as well as in a 9th period beginning in 1980. The flood-rich periods are characterized by longer flood durations. Most of the flood-rich and flood-poor periods (in particular the beginning and the end of them can be connected to changes in natural climate variability. These include changing sunspot numbers (as a measure of solar activity, so-called Little Ice Age Type Events (LIATEs as well as changes in the North Atlantic Oscillation (NAO. Climate signals from external forcing factors, which could be used to explain the changing flood frequencies in the Bavarian Alpine Foreland, end in 1930. Relationships within the climate system such as the correlation of flood frequencies with the NAO have changed during the transition from the post Little Ice Age period to the Modern Climate Optimum around 1930. Natural climate variability might have been outperformed by anthropogenic climate change.

  18. RNA Sequencing Analysis Reveals Transcriptomic Variations in Tobacco (Nicotiana tabacum Leaves Affected by Climate, Soil, and Tillage Factors

    Directory of Open Access Journals (Sweden)

    Bo Lei

    2014-04-01

    Full Text Available The growth and development of plants are sensitive to their surroundings. Although numerous studies have analyzed plant transcriptomic variation, few have quantified the effect of combinations of factors or identified factor-specific effects. In this study, we performed RNA sequencing (RNA-seq analysis on tobacco leaves derived from 10 treatment combinations of three groups of ecological factors, i.e., climate factors (CFs, soil factors (SFs, and tillage factors (TFs. We detected 4980, 2916, and 1605 differentially expressed genes (DEGs that were affected by CFs, SFs, and TFs, which included 2703, 768, and 507 specific and 703 common DEGs (simultaneously regulated by CFs, SFs, and TFs, respectively. GO and KEGG enrichment analyses showed that genes involved in abiotic stress responses and secondary metabolic pathways were overrepresented in the common and CF-specific DEGs. In addition, we noted enrichment in CF-specific DEGs related to the circadian rhythm, SF-specific DEGs involved in mineral nutrient absorption and transport, and SF- and TF-specific DEGs associated with photosynthesis. Based on these results, we propose a model that explains how plants adapt to various ecological factors at the transcriptomic level. Additionally, the identified DEGs lay the foundation for future investigations of stress resistance, circadian rhythm and photosynthesis in tobacco.

  19. Temporal dynamics and impact of climate factors on the incidence of zoonotic cutaneous leishmaniasis in central Tunisia.

    Directory of Open Access Journals (Sweden)

    Amine Toumi

    Full Text Available BACKGROUND: Old world Zoonotic Cutaneous Leishmaniasis (ZCL is a vector-borne human disease caused by Leishmania major, a unicellular eukaryotic parasite transmitted by pool blood-feeding sand flies mainly to wild rodents, such as Psammomys obesus. The human beings who share the rodent and sand fly habitats can be subverted as both sand fly blood resource. ZCL is endemic in the Middle East, Central Asia, Subsaharan and North Africa. Like other vector-borne diseases, the incidence of ZCL displayed by humans varies with environmental and climate factors. However, so far no study has addressed the temporal dynamics or the impact of climate factors on the ZCL risk. PRINCIPAL FINDINGS: Seasonality during the same epidemiologic year and interval between ZCL epidemics ranging from 4 to 7 years were demonstrated. Models showed that ZCL incidence is raising i by 1.8% (95% confidence intervals CI:0.0-3.6% when there is 1 mm increase in the rainfall lagged by 12 to 14 months ii by 5.0% (95% CI: 0.8-9.4% when there is a 1% increase in humidity from July to September in the same epidemiologic year. CONCLUSION/SIGNIFICANCE: Higher rainfall is expected to result in increased density of chenopods, a halophytic plant that constitutes the exclusive food of Psammomys obesus. Consequently, following a high density of Psammomys obesus, the pool of Leishmania major transmissible from the rodents to blood-feeding female sand flies could lead to a higher probability of transmission to humans over the next season. These findings provide the evidence that ZCL is highly influenced by climate factors that could affect both Psammomys obesus and the sand fly population densities.

  20. Climate Factors as Important Determinants of Dengue Incidence in Curaçao.

    Science.gov (United States)

    Limper, M; Thai, K T D; Gerstenbluth, I; Osterhaus, A D M E; Duits, A J; van Gorp, E C M

    2016-03-01

    Macro- and microclimates may have variable impact on dengue incidence in different settings. We estimated the short-term impact and delayed effects of climate variables on dengue morbidity in Curaçao. Monthly dengue incidence data from 1999 to 2009 were included to estimate the short-term influences of climate variables by employing wavelet analysis, generalized additive models (GAM) and distributed lag nonlinear models (DLNM) on rainfall, temperature and relative humidity in relation to dengue incidence. Dengue incidence showed a significant irregular 4-year multi-annual cycle associated with climate variables. Based on GAM, temperature showed a U-shape, while humidity and rainfall exhibited a dome-shaped association, suggesting that deviation from mean temperature increases and deviation from mean humidity and rainfall decreases dengue incidence, respectively. Rainfall was associated with an immediate increase in dengue incidence of 4.1% (95% CI: 2.2-8.1%) after a 10-mm increase, with a maximum increase of 6.5% (95% CI: 3.2-10.0%) after 1.5 month lag. A 1 °C decrease of mean temperature was associated with a RR of 17.4% (95% CI: 11.2-27.0%); the effect was inversed for a 1°C increase of mean temperature (RR= 0.457, 95% CI: 0.278-0.752). Climate variables are important determinants of dengue incidence and provide insight into its short-term effects. An increase in mean temperature was associated with lower dengue incidence, whereas lower temperatures were associated with higher dengue incidence. PMID:26122819

  1. Impact of Pollution, Climate, and Socio-demographic Factors on Spatiotemporal Dynamics of Seasonal Respiratory Viruses

    OpenAIRE

    Sloan, Chantel; Moore, Martin L.; Hartert, Tina

    2011-01-01

    Seasonal viruses present a major cause of morbidity and mortality in temperate climates. Through major pandemics and smaller annual epidemics, viruses such as influenza, respiratory syncytial virus (RSV) and human rhinovirus (HRV) result in lost school and work days for most that are infected and more serious complications for the immunocompromised. The reasons for these viruses showing strict seasonality include but are not limited to the influence of cold weather and humidity on virus parti...

  2. Greenhouse Gas Emission Factor Module: Land Use in Rural New Zealand—Climate Version 1

    OpenAIRE

    Hendy, Joanna; Kerr, Suzi

    2005-01-01

    Several different New Zealand economic models produce measures of rural economic activity that have greenhouse gas implications. For climate change analysis, models need to translate economic activity into greenhouse gas emissions. This document estimates functions and creates projections for land-use related greenhouse gas emissions per unit of economic activity that are simple; are based on readily available data and strong science; are consistent with the national inventory in 2002; evolve...

  3. How Climate Factors Influenced the Spatial Allocation of and Returns to Texas Cattle Breeds

    OpenAIRE

    YUQUAN W. ZHANG; Hagerman, Amy D.; McCarl, Bruce A

    2011-01-01

    A multivariate binary choice model is used to examine the climate effects on cattle breed selection across Texas counties. Angus, Brangus, and Brahman are considered in the model. Results suggest that it is more efficient to estimate the binary choice equations jointly than separately. Counties having higher summer temperatures are more likely to choose Brahman and warmer winters increase the likelihood of adopting Brangus and Brahman. Angus price imposes positive effects on both Angus and Br...

  4. Hydrologic factors controlling groundwater salinity in northwestern coastal zone, Egypt

    Indian Academy of Sciences (India)

    Nahla A Morad; M H Masoud; S M Abdel Moghith

    2014-10-01

    The aim of this article is to assess the main factors influencing salinity of groundwater in the coastal area between El Dabaa and Sidi Barani, Egypt. The types and ages of the main aquifers in this area are the fractured limestone of Middle Miocene, the calcareous sandstone of Pliocene and the Oolitic Limestone of Pleistocene age. The aquifers in the area are recharged by seasonal rainfall of the order of 150 mm/year. The relationship of groundwater salinity against the absolute water level, the well drilling depth, and the ability of aquifer to recharge has been discussed in the present work. The ability of aquifer to locally recharge by direct rainfall is a measure of the vertical permeability due to lithological and structural factors that control groundwater salinity in the investigated aquifers. On the other hand, the fracturing system as well as the attitude of the surface water divide has a prime role in changing both the mode of occurrence and the salinity of groundwater in the area. Directly to the west of Matrouh, where the coastal plain is the narrowest, and east of Barrani, where the coastal plain is the widest, are good examples of this concept, where the water salinity attains its maximum and minimum limits respectively. Accordingly, well drilling in the Miocene aquifer, in the area between El Negila and Barrani to get groundwater of salinities less than 5000 mg/l is recommended in this area, at flow rate less than 10m3/hr/well. In other words, one can expect that the brackish water is probably found where the surface water divide is far from the shore line, where the Wadi fill deposits dominate (Quaternary aquifer), acting as a possible water salinity by direct rainfall and runoff.

  5. Climatic factors associated with reproductive performance in English Berkshire pigs and crossbred pigs between Landrace and Large White raised in a subtropical climate region of Japan.

    Science.gov (United States)

    Usui, Shiho; Koketsu, Yuzo

    2015-12-01

    Our objective was to characterize Berkshire female pigs associated with climatic factors by examining the interactions between two pig groups (pure English Berkshire females and crossbred females between Landrace and Large White) for reproductive performance in a humid subtropical zone. We analyzed 63,227 first-service records of 11,992 females in 12 herds. Climate data were obtained from four weather stations located close to the herds. Mean daily maximum temperatures (Tmax) and daily average relative humidity (ARH) for different time periods around servicing and farrowing of each female were coordinated with that female's reproductive performance data. Multilevel mixed-effects models were applied to the data. There were two-way interactions between the pig groups and either Tmax or ARH for weaning-to-first-mating interval (WMI) and number of total pigs born (TPB; P < 0.05). The WMI in Berkshire sows increased by 0.64 days as Tmax increased from 20 to 30 °C (P < 0.05), whereas in crossbred sows it only increased by 0.09 days over the same Tmax range. In contrast, WMI in Berkshire sows only increased by 0.01 days as ARH increased from 60 to 80 % (P < 0.05), whereas in crossbred sows it increased by 0.32 days. In Berkshire females, TPB decreased by 0.3 pigs as Tmax increased from 20 to 30 °C (P < 0.05), whereas that in crossbred females decreased by 0.4 pigs (P < 0.05). Therefore, we recommend producers apply advanced cooling systems for Berkshire females.

  6. 75 FR 69912 - Pipeline Safety: Control Room Management/Human Factors

    Science.gov (United States)

    2010-11-16

    ... Safety: Control Room Management/Human Factors AGENCY: Pipeline and Hazardous Materials Safety..., 2010, PHMSA published a Control Room Management/Human Factors notice of proposed rulemaking (NPRM... to expedite the program implementation deadlines of the Control Room Management/Human Factors rule...

  7. 75 FR 5536 - Pipeline Safety: Control Room Management/Human Factors, Correction

    Science.gov (United States)

    2010-02-03

    ... Safety: Control Room Management/Human Factors, Correction AGENCY: Pipeline and Hazardous Materials Safety... Regulations to address human factors and other aspects of control room management for pipelines where... 63310) entitled ``Pipeline Safety: Control Room Management/Human Factors.'' This final rule...

  8. 76 FR 35130 - Pipeline Safety: Control Room Management/Human Factors

    Science.gov (United States)

    2011-06-16

    ... FR 5536). By this amendment to the Control Room Management/Human Factors (CRM) rule, an operator must... Safety: Control Room Management/Human Factors AGENCY: Pipeline and Hazardous Materials Safety... deadlines in the Control Room Management/Human Factors regulations in order to realize the safety...

  9. Spatial-temporal patterns of water use efficiency and climate controls in China's Loess Plateau during 2000-2010.

    Science.gov (United States)

    Zhang, Tian; Peng, Jian; Liang, Wei; Yang, Yuting; Liu, Yanxu

    2016-09-15

    Accurate assessments of spatial-temporal variations in water use efficiency (WUE) are important for evaluation of carbon and water balances. In this study, the spatial and temporal patterns of WUE and associated climate controls in China's Loess Plateau are investigated over 2000-2010 by utilizing remote sensing data and multiple statistical methods; which provides a greater understanding about how WUE changed after the Grain to Green Program (GTGP) launched. Carbon sequestration (i.e., net primary productivity, NPP) is estimated with the CASA model and water consumption (i.e., evapotranspiration, ET) is obtained from the MODIS product (i.e., MOD16). Our results identify an increasing trend in the regional mean NPP that amounted to 7.593gC/m(2)·yr with an average value of 310.035gC/m(2)·yr. Changes in ET are segmented into three stages, the growth (2000-2003), decline (2004-2006) and stable (2007-2010) stages. Regional WUE is measured at 0.915gC/mm·m(2) and shows an upward trend at a rate of 0.027gC/mm·m(2)·yr. Spatially, significant regional heterogeneity is found in both NPP and WUE with gradients decreasing from the southeast to the northwest, but sharp rises detected in northern Shaanxi. At the biome level, the annual average WUE of the four groups decrease in the order of grasslands>woodlands>shrublands>croplands. Moreover, all biomes in the grassland ecosystems exhibit a growth in WUE as does the arid desert zone in the northwestern region, suggesting that vegetation in moderately water-deficient areas may have a higher tolerance to drought. Among different meteorological factors, precipitation and drought severity index (DSI) in the Loess Plateau show a latitudinal zonality and influences the WUE, which indicated that the moisture rather than temperature would be the major control factor of the regional WUE. Finally, significant variation in vegetation WUE sensitivity in response to meteorological factors is noted. Temperature is found to be the

  10. Climate control on ancestral population dynamics: insight from Patagonian fish phylogeography.

    Science.gov (United States)

    Ruzzante, Daniel E; Walde, Sandra J; Gosse, John C; Cussac, Victor E; Habit, Evelyn; Zemlak, Tyler S; Adams, Emily D M

    2008-05-01

    Changes in lake and stream habitats during the growth and retreat of Pleistocene glaciers repeatedly altered the spatial distributions and population sizes of the aquatic fauna of the southern Andes. Here, we use variation in mtDNA control region sequences to infer the temporal dynamics of two species of southern Andean fish during the past few million years. At least five important climate events were associated with major demographic changes: (i) the widespread glaciations of the mid-Pliocene (c. 3.5 Ma); (ii) the largest Patagonian glaciation (1.1 Ma); (iii) the coldest Pleistocene glaciation as indicated by stacked marine delta(18)O (c. 0.7 Ma); (iv) the last southern Patagonian glaciation to reach the Atlantic coast (180 ka); and (v) the last glacial maximum (LGM, 23-25,000 years ago). The colder-water inhabitant, Galaxias platei, underwent a strong bottleneck during the LGM and its haplotype diversity coalesces c. 0.7 Ma. In contrast, the more warm-adapted and widely distributed Percichthys trucha showed continuous growth through the last two glacial cycles but went through an important bottleneck c. 180,000 years ago, at which time populations east of the Andes may have been eliminated. Haplotype diversity of the most divergent P. trucha populations, found west of the Andes, coalesces c. 3.2 Ma. The demographic timelines obtained for the two species thus illustrate the continent-wide response of aquatic life in Patagonia to climate change during the Pleistocene, but also show how differing ecological traits and distributions led to distinctive responses. PMID:18363661

  11. Control of shortwave radiation parameterization on tropical climate SST-forced simulation

    Science.gov (United States)

    Crétat, Julien; Masson, Sébastien; Berthet, Sarah; Samson, Guillaume; Terray, Pascal; Dudhia, Jimy; Pinsard, Françoise; Hourdin, Christophe

    2016-09-01

    SST-forced tropical-channel simulations are used to quantify the control of shortwave (SW) parameterization on the mean tropical climate compared to other major model settings (convection, boundary layer turbulence, vertical and horizontal resolutions), and to pinpoint the physical mechanisms whereby this control manifests. Analyses focus on the spatial distribution and magnitude of the net SW radiation budget at the surface (SWnet_SFC), latent heat fluxes, and rainfall at the annual timescale. The model skill and sensitivity to the tested settings are quantified relative to observations and using an ensemble approach. Persistent biases include overestimated SWnet_SFC and too intense hydrological cycle. However, model skill is mainly controlled by SW parameterization, especially the magnitude of SWnet_SFC and rainfall and both the spatial distribution and magnitude of latent heat fluxes over ocean. On the other hand, the spatial distribution of continental rainfall (SWnet_SFC) is mainly influenced by convection parameterization and horizontal resolution (boundary layer parameterization and orography). Physical understanding of the control of SW parameterization is addressed by analyzing the thermal structure of the atmosphere and conducting sensitivity experiments to O3 absorption and SW scattering coefficient. SW parameterization shapes the stability of the atmosphere in two different ways according to whether surface is coupled to atmosphere or not, while O3 absorption has minor effects in our simulations. Over SST-prescribed regions, increasing the amount of SW absorption warms the atmosphere only because surface temperatures are fixed, resulting in increased atmospheric stability. Over land-atmosphere coupled regions, increasing SW absorption warms both atmospheric and surface temperatures, leading to a shift towards a warmer state and a more intense hydrological cycle. This turns in reversal model behavior between land and sea points, with the SW scheme that

  12. On the relative importance of the climate change factors along the river Scheldt considering climate scenarios for upstream inland and downstream coastal (mean sea level and surge) boundary conditions

    Science.gov (United States)

    Ntegeka, V.; Willems, P.; Monbaliu, J.

    2012-04-01

    To improve on the efficacy of flood risk mitigation measures, it is essential to investigate the relative importance of the future impact pressures. This is more so in areas which are found to be hot spots for flooding. One such area was identified in the Scheldt region located in Belgium. The Dendermonde area is a place where both the downstream coastal and the upstream river flow boundary conditions interact and jointly control the flood risk. Downstream of this area, the coastal level changes include both the sea level rise and storm surge changes due to climate change impacts on the wind climate over the North Atlantic and North Sea region. Upstream of the Dendermonde area lies the Dender river which introduces an extra pressure on the Dendermonde area. Against this back drop, impact analysis was performed using a hydrodynamic model that accounts for such changes. The climate data for future scenarios were extracted from the climate databases PRUDENCE (http://prudence.dmi.dk), ENSEMBLES (http://www.ensembles-eu.org/), IPCC AR4 (www-pcmdi.llnl.gov/ipcc/about_ipcc.php) and CERA (CLM from MPI-M/MaD). Future changes were derived from the large ensemble set of climate model runs and their effects simulated in the hydrodynamic model based on statistically processed climate change scenarios of sea level rise, SLP change and related storm surge changes and upstream runoff due to changes in rainfall and potential evapotranspiration. Changes in SLP were transferred to changes in storm surges at the Scheldt mouth (at Vlissingen) based on a correlation model between the SLP at the Baltic Sea and the storm surge level. This model was derived after analysis of SLP composite maps and SLP-surge correlation maps for days where the surge exceeds given thresholds (for different return periods). Correlations between the inland (rainfall, runoff) and coastal climatic changes were considered. The impact analysis to analyze the importance of the pressures for the Dendermonde area was

  13. Factors Affecting Farmers’ Adaptation Strategies to Environmental Degradation and Climate Change Effects: A Farm Level Study in Bangladesh

    Directory of Open Access Journals (Sweden)

    Mohammed Nasir Uddin

    2014-09-01

    Full Text Available Offering a case study of coastal Bangladesh, this study examines the adaptation of agriculturalists to degrading environmental conditions likely to be caused or exacerbated under global climate change. It examines four central components: (1 the rate of self-reported adoption of adaptive mechanisms (coping strategies as a result of changes in climate; (2 ranking the potential coping strategies based on their perceived importance to agricultural enterprises; (3 identification the socio-economic factors associated with adoption of coping strategies, and (4 ranking potential constraints to adoption of coping strategies based on farmers’ reporting on the degree to which they face these constraints. As a preliminary matter, this paper also reports on the perceptions of farmers in the study about their experiences with climatic change. The research area is comprised of three villages in the coastal region (Sathkhira district, a geographic region which climate change literature has highlighted as prone to accelerated degradation. One-hundred (100 farmers participated in the project’s survey, from which the data was used to calculate weighted indexes for rankings and to perform logistic regression. The rankings, model results, and descriptive statistics, are reported here. Results showed that a majority of the farmers self-identified as having engaged in adaptive behavior. Out of 14 adaptation strategies, irrigation ranked first among farm adaptive measures, while crop insurance has ranked as least utilized. The logit model explained that out of eight factors surveyed, age, education, family size, farm size, family income, and involvement in cooperatives were significantly related to self-reported adaptation. Despite different support and technological interventions being available, lack of available water, shortage of cultivable land, and unpredictable weather ranked highest as the respondent group’s constraints to coping with environmental

  14. Climate modulated erosion and sediment flux control offshore crustal structure at South China Sea continental margin

    Science.gov (United States)

    Clift, P. D.; Brune, S.; Quinteros, J.

    2015-12-01

    Rifted continental lithosphere subsides as a consequence of combined crustal thinning and mantle lithosphere cooling yet basins on some continental margins experience anomalous subsidence events that postdate active extension. Deep basins on the northern margin of the South China Sea, notably the Baiyun Sag, show basement subsidence accelerating after ~21 Ma, postdating extension by several million years. Similar subsidence events are seen after 5 Ma in the Song Hong Basin and after 11 Ma in the Qiongdongnan Basin. We combine geophysical observations and numerical forward modeling to show that loading of the offshore basins by increased sediment flux caused by faster onshore erosion following Early Miocene monsoon intensification is a viable trigger for ductile flow after the cessation of active extension. Loading works in conjunction with onshore uplift to drive flow of the lower crust away from the rift axis. As well as sediment supply rates distribution patterns and drainage capture can be significant in controlling crustal flow and thinning. This illustrates that offshore basin dynamics at continental margins with weak crust can be controlled by onshore surface processes in a newly recognized form of climate-tectonic coupling.

  15. Impact of Real-world Factors Influencing Investment Decisions on the Costs and Distribution of Climate Change Mitigation

    Science.gov (United States)

    Edmonds, J.; Iyer, G.; McJeon, H. C.; Leon, C.; Hultman, N.

    2015-12-01

    Strategies to mitigate dangerous anthropogenic climate change require a dramatic transformation of the energy system to reduce greenhouse gas emissions, that in turn requires large-scale investments. Investment decisions depend not only on investment capital availability but also on investment risks. A number of factors such as national policy environments, quality of public and private institutions, sector, firm and technology specific characteristics can affect investors' assessments of risks, leading to a wide variation in the business climate for investment. Such heterogeneity in investment risks can have important implications, as investors usually respond to risks by requiring higher returns for riskier projects; delaying or forgoing the investments; or preferring to invest in existing, familiar projects. We study the impact of variation in investment risks on regional patterns of emissions mitigation, the cost of emissions mitigation and patterns of technology deployment. We modify an integrated assessment model, widely used in global climate policy analyses (the Global Change Assessment Model) and incorporate decisions on investments based on risks along two dimensions. Along the first dimension, we vary perceived risks associated with particular technologies. To do so, we assign a higher cost of capital for investment in low-carbon technologies as these involve intrinsically higher levels of regulatory and market risk. The second dimension uses a proxy to vary investment risks across regions, based on an institutional quality metric published by the World Economic Forum. Explicit representation of investment risks has two major effects. First, it raises the cost of emissions mitigation relative to a world with uniform investment risks. Second, it shifts the pattern of emissions mitigation, with industrialized countries mitigating more, and developing countries mitigating less. Our results suggest that institutional reforms aimed at lowering investment

  16. Factors Influencing Compliance with Infection Control Practice in Japanese Dentists

    Directory of Open Access Journals (Sweden)

    A Tada

    2014-01-01

    Full Text Available Background: In recent years, dentists have more opportunity of treating patients infected with blood-borne pathogens. Although compliance with infection control practice (ICP in dental practice is required, it is not still sufficiently spread in Japan.Objective: To identify factors associated with compliance with ICPs in the population of Japanese dentists.Methods: In a questionnaire-based cross-sectional study in 2009, 2134 dentists in Aichi prefecture, Japan, were surveyed. They were asked for their demographic characteristics, willingness to treat HIV/AIDS patients, and knowledge about universal/standard precautions and ICP.Results: Many ICP items had significant association with age, specialty for oral surgery, number of patients treated per day, willingness to treat HIV/AIDS patients and knowledge about the universal/standard precautions. In logistic regression model, knowledge about the precautions had significant associations with all ICP items. Among participants with disadvantageous characteristic group for ICP (ie, age ≥50 years, being general dentist, and treating ≤35 patients/day, knowledge about the universal/standard precautions had greater impact on exchanging handpiece for each patient and installing extra-oral vacuum in those with age of ≥50 years than in those who visited ≤35 patient per day.Conclusion: Knowledge about the meaning of universal/standard precautions is the most significant predictor of compliance with ICPs among Japanese dentists.

  17. Climate controls on late Pleistocene landscape evolution of the Okhombe valley, KwaZulu-Natal, South Africa

    NARCIS (Netherlands)

    Temme, A.J.A.M.; Baartman, J.E.M.; Botha, G.A.; Veldkamp, A.; Jongmans, A.G.; Wallinga, J.

    2008-01-01

    Hillslopes in central and western parts of KwaZulu-Natal, South Africa are often mantled by colluvial sediments of the Masotcheni Formation. These sediments have accreted in response to several cycles of deposition, pedogenesis and incomplete erosion. Climatic controls on these cycles are incomplete

  18. Regulation in climate control engineering. Refrigeration, air conditioning, space heating; Regulation en genie climatique. Froid, climatisation, chauffage

    Energy Technology Data Exchange (ETDEWEB)

    Desmons, J.

    2005-04-01

    After a recall of some basic concepts of electronics and hydraulics, this book presents some methodological and technological elements about regulation in climate control engineering. It explains how to design and implement regulation systems and how to practice their maintenance. It presents several practical cases of real installations. (J.S.)

  19. Empathy and Effortful Control Effects on Early Adolescents' Aggression: When Do Students' Perceptions of Their School Climate Matter?

    Science.gov (United States)

    Batanova, Milena; Loukas, Alexandra

    2016-01-01

    Guided by the social emotional learning framework, this study examined whether early adolescents' social awareness (empathic concern, perspective taking) and self-management (effortful control) would uniquely contribute to early adolescents' subsequent forms of aggression, and whether perceptions of their school climate (friction, cohesion,…

  20. Characteristics of nitrogen mineralization rates and controlling factors in forest soils in Japanese archipelago

    Science.gov (United States)

    Urakawa, R.; Ohte, N.; Shibata, H.; Isobe, K.; Oda, T.; Watanabe, T.; Fukuzawa, K.; Ugawa, S.; Hishi, T.; Enoki, T.; Tateno, R.; Fukushima, K.; Nakanishi, A.; Saigusa, N.; Yamao, Y.; Oyanagi, N.; Hattori, D.; Nakata, M.; Kenta, T.; Toda, H.; Inagaki, Y.; Hirai, K.

    2013-12-01

    1. Introduction The nitrogen (N) dynamics in forest soils in the Japanese archipelago varies widely because it extends for 3000 km and the climatic zone ranges from cool-temperate to subtropical region. Therefore, it is necessary to understand the soil N transformation characteristics and its controlling factors across a wide area because the changes in N dynamics due to the climate change are expected to differ from region to region. In this study, we selected more than 30 sites from across the Japanese archipelago and measured net rates of soil N mineralization and nitrification. Also, we measured the physical, chemical and biological properties of soil to clarify the controlling factors. 2. Materials and methods We established an experimental plot (20 * 20 m) at each site, and at each plot, five soil sampling locations were established. At each sampling location, mineral soil samples were collected from 0-10, 10-30, 30-50 cm in depth. Net and gross N mineralization and nitrification rate, soil pH(H2O), water soluble cation (Ca2+, Mg2+, K+, Na+, NH4+, Al3+), anion (Cl-, NO3-, SO42-), and organic carbon (WSOC) were measured. From the net N mineralization and nitrification rate measured by laboratory incubation at three different temperatures (15, 20, 25 °C), Q10min, Q10nit (Q10 of N mineralization and nitrification) and average net rate at 20 °C (N20min and N20nit) were calculated. 3. Results and discussion In most of the sites, net N mineralization and nitrification rates were higher in the shallower soil layers. N20min and N20nit ranged 0.01-3.23 and 0.00-3.00 mgN/kg/d, respectively and Q10min and Q10nit ranged 1.09-24.16 and 1.38-20.10 respectively. There was a pattern that low rates soil (N20 Soils which had high N mineralization rates had also high nitrification rates. Soils with high N mineralization and nitrification rate were mostly located in the northern region (Hokkaido Island and Tohoku region) in Japan. This suggests that soil type distribution in

  1. Climatic and biotic controls on annual carbon storage in Amazonian ecosystems

    Science.gov (United States)

    Tian, H.; Melillo, J.M.; Kicklighter, D.W.; McGuire, A.D.; Helfrich, J.; Moore, B.; Vorosmarty, C.J.

    2000-01-01

    1 The role of undisturbed tropical land ecosystems in the global carbon budget is not well understood. It has been suggested that inter-annual climate variability can affect the capacity of these ecosystems to store carbon in the short term. In this paper, we use a transient version of the Terrestrial Ecosystem Model (TEM) to estimate annual carbon storage in undisturbed Amazonian ecosystems during the period 1980-94, and to understand the underlying causes of the year-to-year variations in net carbon storage for this region. 2 We estimate that the total carbon storage in the undisturbed ecosystems of the Amazon Basin in 1980 was 127.6 Pg C, with about 94.3 Pg C in vegetation and 33.3 Pg C in the reactive pool of soil organic carbon. About 83% of the total carbon storage occurred in tropical evergreen forests. Based on our model's results, we estimate that, over the past 15 years, the total carbon storage has increased by 3.1 Pg C (+ 2%), with a 1.9-Pg C (+2%) increase in vegetation carbon and a 1.2-Pg C (+4%) increase in reactive soil organic carbon. The modelled results indicate that the largest relative changes in net carbon storage have occurred in tropical deciduous forests, but that the largest absolute changes in net carbon storage have occurred in the moist and wet forests of the Basin. 3 Our results show that the strength of interannual variations in net carbon storage of undisturbed ecosystems in the Amazon Basin varies from a carbon source of 0.2 Pg C/year to a carbon sink of 0.7 Pg C/year. Precipitation, especially the amount received during the drier months, appears to be a major controller of annual net carbon storage in the Amazon Basin. Our analysis indicates further that changes in precipitation combine with changes in temperature to affect net carbon storage through influencing soil moisture and nutrient availability. 4 On average, our results suggest that the undisturbed Amazonian ecosystems accumulated 0.2 Pg C/year as a result of climate

  2. Holocene Fire, Climate and Erosion in the Jemez Mountains, New Mexico: Natural and Anthropogenic Controls

    Science.gov (United States)

    Meyer, G. A.; Fitch, E. P.

    2013-12-01

    Ponderosa pine and mixed-conifer forests in the Jemez Mountains have been ravaged by extensive severe fires in the last two decades, which burned almost 1000 km2, roughly 30% of this middle-elevation range. Tree-ring fire history reconstructions indicate that a low-severity fire regime characterized the ca. 400 years before Euroamerican settlement, and that fuel buildup from fire suppression and land-use impacts contributed to increased fire severity in recent years. In order to better understand natural variability, climatic influences, and erosional effects of wildfire activity since ~5000 cal yr BP, we identified and 14C-dated fire-related alluvial deposits in the 2002 Lakes Fire area in the southwestern Jemez Mountains. These deposits indicate that most late Holocene fire-related erosional events were relatively minor, consistent with the low-severity burns that dominate the tree-ring record, but larger debris flows also occurred, suggesting at least small areas of high-severity fire. Although changes in postfire sedimentation are not so clearly related to millennial-scale Holocene climatic changes as in the Northern Rocky Mountains, peaks in fire-event probability correspond with severe regional multidecadal droughts ca. 1800 and 375 cal yr BP. Local microclimatic controls on vegetation, soils, and post-fire sedimentation are also evident. Relatively dense mixed-conifer stands including Douglas-fir typify moister north-facing basins, where soils are apparently thicker and more permeable than on southerly aspects. Alluvial fans of these basins are dominated by fire-related deposits (77% of measured stratigraphic thickness), thus we interpret that little erosion occurs in the absence of wildfires. Holocene fire-related events from north slopes are also of somewhat lower frequency, and possibly of higher severity. In contrast, in ponderosa pine-dominated south-facing basins, fire-related deposits make up only 39% of measured fan deposits. On drier south aspects

  3. Climate factors affecting fertility after cervical insemination during the first months of the breeding season in Rasa Aragonesa ewes

    Science.gov (United States)

    Santolaria, P.; Yániz, J.; Fantova, E.; Vicente-Fiel, S.; Palacín, I.

    2014-09-01

    This study was carried out to examine the impact of several climate variables on the pregnancy rate after cervical artificial insemination (AI) of Rasa Aragonesa ewes. Data were derived from 8,977 inseminations in 76 well-managed flocks performed during the first month of the breeding season (July to October). The following data were recorded for each animal: farm, year, month of AI, parity, lambing-treatment interval, inseminating ram, AI technician, and climatic variables such as mean, maximum and minimum temperature, mean and maximum relative humidity, rainfall, and mean and maximum temperature-humidity index (THI) for each day from day 12 before AI to day 14 post-AI. Means were furthermore calculated for the following periods around AI (day 0): -12 to 0, -2 to 0, AI day, 0 to 2, and 0 to 14. Logistic regression analysis indicated that the likelihood of pregnancy decreased when maximum temperature in the 2 days prior to AI was higher than 30 °C (by a factor of 0.81). Fertility was also lower for primiparous ewes and in multiparous ewes with more than five previous parturitions. Other factors with significant impact on fertility were flock, technician, inseminating ram, and a lambing-AI interval longer than 240 days. It was concluded that the 2 days prior to AI seems to be the period when heat stress had the greatest impact on pregnancy rate in Rasa Aragonesa ewes.

  4. Tropical West Pacific moisture dynamics and climate controls on rainfall isotopic ratios in southern Papua, Indonesia

    Science.gov (United States)

    Permana, Donaldi S.; Thompson, Lonnie G.; Setyadi, Gesang

    2016-03-01

    Understanding the controls on stable isotopologues of tropical rainfall is critical for paleoclimatic reconstruction from tropical ice core records. The southern Papua region, Indonesia, has a unique climate regime that allows for the evaluation of the influence of precipitation and convective activity on seasonal rainfall δ18O. The influence of the El Niño-Southern Oscillation (ENSO) on interannual rainfall δ18O variation is also important for paleoclimate reconstruction. Here we present stable isotope analyses of 1332 rain samples collected daily during the period from January 2013 to February 2014 (ENSO-normal) and December 2014 to September 2015 (El Niño) at various elevation stations (9 to 3945 m above sea level) on the southern slope of the central mountain ranges in Papua. The results suggest an altitude effect with an isotopic lapse rate for δ18O (δD) of -2.4‰/km (-18.2‰/km). The temporal δ18O variability (daily to interannual) is controlled mostly by regional convective activity rather than local/regional precipitation amount. The intraseasonal δ18O variation resembles the Madden-Julian Oscillation cycle with major δ18O depletion events associated with active (wet) phases. Moisture origins, transport pathways, moisture convergence, and raindrop evaporation appear to have no significant seasonal effects on δ18O, leading to the conclusion that condensation temperature controls δ18O depletion associated with convective activity. Seasonal δ18O variation is likely associated with atmospheric temperature at the mean condensation level as indicated by the altitude of latent heat release in the troposphere. Rainfall δ18O (δD) is generally enriched by 1.6‰-2‰ (11‰-15‰) during El Niño than during ENSO-normal periods.

  5. Climate change and climate systems influence and control the atmospheric dispersion of desert dust: implications for human health

    Science.gov (United States)

    Griffin, Dale W.

    2010-01-01

    The global dispersion of desert dust through Earth’s atmosphere is greatly influenced by temperature. Temporal analyses of ice core data have demonstrated that enhanced dust dispersion occurs during glacial events. This is due to an increase in ice cover, which results in an increase in drier terrestrial cover. A shorter temporal analysis of dust dispersion data over the last 40 years has demonstrated an increase in dust transport. Climate systems or events such as the North Atlantic Oscillation, the Indian Ocean subtropical High, Pacific Decadal Oscillation, and El Nino-Sothern Oscillation are known to influence global short-term dust dispersion occurrence and transport routes. Anthropogenic influences on dust transport include deforestation, harmful use of topsoil for agriculture as observed during the American Dust Bowl period, and the creation of dry seas (Aral Sea) and lakes (Lake Owens in California and Lake Chad in North Africa) through the diversion of source waters (for irrigation and drinking water supplies). Constituents of desert dust both from source regions (pathogenic microorganisms, organic and inorganic toxins) and those scavenged through atmospheric transport (i.e., industrial and agricultural emissions) are known to directly impact human and ecosystem health. This presentation will present a review of global scale dust storms and how these events can be both a detriment and benefit to various organisms in downwind environments.

  6. Forestry Canada's perspectives on climate change

    International Nuclear Information System (INIS)

    The impacts of climatic change on Canada's forestry sector are discussed, in the context of major research priorities relating to forecasting climate, forecasting forest responses, monitoring changes, mitigating effects, and understanding the forest carbon balance. There are five major concerns that affect policy decisions: effects of climatic change on forests; adaptation to climate change; impacts of changing crops on forestry; changing forestry values in changing sociological settings; and international implications of the changing climate. A scientific program to respond to climate change issues is required, and should include the following concentrations of research effort. Planning requires projections of likely future climates, and efforts should concern relations between pre-historic climates and forest ecosystems and integrating data into predictive models. Forecasting of response of forests should include tree physiology, factors controlling reforestation, variations in forest trees, effects of pollutants, damage to forests, and forest decline

  7. Atmospheric Deposition of Organic Carbon in Pennsylvania as Affected by Climatic Factors

    Science.gov (United States)

    Iavorivska, L.; Boyer, E. W.; Grimm, J.; Fuentes, J. D.

    2014-12-01

    Organic matter which is usually expressed through measurements of dissolved organic carbon (DOC) is ubiquitous in atmospheric water. It plays an important role in cloud formation processes, and contributes to organic acidity of precipitation. Rain and snow deposited to the landscape is a source of nutrient enrichment to ecosystems and water bodies, and is especially important as an input of carbon in coastal regions. Since DOC is highly chemically reactive and bioavailable it influences rates of primary and secondary productivity in aquatic ecosystems. Despite the significance of DOC to many ecosystem processes, knowledge about its contributions to landscapes in precipitation remains limited. Here, we quantified the removal of DOC from the atmosphere via precipitation over space and time in order to assess the magnitude of wet deposition as a link between terrestrial and aquatic components of the carbon cycle. Further, we consider the predictability of organic matter in precipitation as a function of hydro-chemical and climatic variables. We measured DOC concentration and composition in storm events both sequentially (hourly during events) and seasonally (weekly over the year). Data on the chemical composition of precipitation, along with meteorological back-trajectory analyses help clarify how an interplay between emission sources, atmospheric transport and climatic conditions determine the abundance of rainwater DOC across Pennsylvania.

  8. Earthquakes as a potential contributing factor to climate change at multi-decadal scale

    Institute of Scientific and Technical Information of China (English)

    KeYan Fang; Heikki Seppä

    2014-01-01

    Climate changes at the multi-decadal scale are often associated with multi-decadal phase shifts of the dominant sea surface temperature (SST) pattern, such as the Pacific Decadal Oscillation (PDO). The PDO may be associated with the North Pacific branch of the Thermohaline Circulation (THC). Great earthquakes (M>8), particularly along the route of the THC, might modulate the vertical mixing and bring deep, cold water to surface, contributing to multi-decadal changes in surface currents and the PDO. This may eventually lead to multi-decadal climate changes. We tested this hypothesis for the Pacific Ocean where great earthquakes have been frequently recorded. We found associations between the PDO and recurrent earthquakes along the route of the deep currents of the THC in the modern period since 1900, and relationships between hydroclimate change in Monsoonal Asia and historical earthquakes since 1300. However, it should be noted that this hypothesis is very preliminary and has many gaps that needs further evidences from more observational records and modeling studies.

  9. Metabolic and Kidney Diseases in the Setting of Climate Change, Water Shortage, and Survival Factors.

    Science.gov (United States)

    Johnson, Richard J; Stenvinkel, Peter; Jensen, Thomas; Lanaspa, Miguel A; Roncal, Carlos; Song, Zhilin; Bankir, Lise; Sánchez-Lozada, Laura G

    2016-08-01

    Climate change (global warming) is leading to an increase in heat extremes and coupled with increasing water shortage, provides a perfect storm for a new era of environmental crises and potentially, new diseases. We use a comparative physiologic approach to show that one of the primary mechanisms by which animals protect themselves against water shortage is to increase fat mass as a means for providing metabolic water. Strong evidence suggests that certain hormones (vasopressin), foods (fructose), and metabolic products (uric acid) function as survival signals to help reduce water loss and store fat (which also provides a source of metabolic water). These mechanisms are intricately linked with each other and stimulated by dehydration and hyperosmolarity. Although these mechanisms were protective in the setting of low sugar and low salt intake in our past, today, the combination of diets high in fructose and salty foods, increasing temperatures, and decreasing available water places these survival signals in overdrive and may be accelerating the obesity and diabetes epidemics. The recent discovery of multiple epidemics of CKD occurring in agricultural workers in hot and humid environments may represent harbingers of the detrimental consequences of the combination of climate change and overactivation of survival pathways.

  10. A review on factors for maximizing solar fraction under wet climate environment in Malaysia

    International Nuclear Information System (INIS)

    Solar energy is the most promising source of clean, renewable energy and it has the greatest potential of any power source to solve the world's energy problems. However, the problem, is how best to harness this vast amount of solar energy. Nevertheless, even if highly efficient Concentrating Solar Power (CSP) could be made cheaply, there would be considerable change in solar power. This technology is expected to be more efficient and to achieve a manufacturing cost of less than $1/W near future. This paper reviews and elaborates the methodology utilized to design and fabricate the solar dish concentrator and outlines the parameters that can be used to increase the efficiency of solar fraction in parabolic dish concentrator under wet climate environment in Malaysia. The study finally provides ideas to the continually increasing ability of these technologies to concentrate and harness solar energy for electricity production and thus eliminate the growing concern over climate change and how it will hurt the region's environment, human health and economy. (author)

  11. Metabolic and Kidney Diseases in the Setting of Climate Change, Water Shortage, and Survival Factors.

    Science.gov (United States)

    Johnson, Richard J; Stenvinkel, Peter; Jensen, Thomas; Lanaspa, Miguel A; Roncal, Carlos; Song, Zhilin; Bankir, Lise; Sánchez-Lozada, Laura G

    2016-08-01

    Climate change (global warming) is leading to an increase in heat extremes and coupled with increasing water shortage, provides a perfect storm for a new era of environmental crises and potentially, new diseases. We use a comparative physiologic approach to show that one of the primary mechanisms by which animals protect themselves against water shortage is to increase fat mass as a means for providing metabolic water. Strong evidence suggests that certain hormones (vasopressin), foods (fructose), and metabolic products (uric acid) function as survival signals to help reduce water loss and store fat (which also provides a source of metabolic water). These mechanisms are intricately linked with each other and stimulated by dehydration and hyperosmolarity. Although these mechanisms were protective in the setting of low sugar and low salt intake in our past, today, the combination of diets high in fructose and salty foods, increasing temperatures, and decreasing available water places these survival signals in overdrive and may be accelerating the obesity and diabetes epidemics. The recent discovery of multiple epidemics of CKD occurring in agricultural workers in hot and humid environments may represent harbingers of the detrimental consequences of the combination of climate change and overactivation of survival pathways. PMID:27283495

  12. Semiempirical modeling of abiotic and biotic factors controlling ecosystem respiration across eddy covariance sites

    NARCIS (Netherlands)

    Migliavacca, M.; Reichstein, M.; Richardson, A.D.; Colombo, R.; Sutton, M.A.; Lasslop, G.; Tomelleri, E.; Wohlfahrt, G.; Carvalhais, N.; Molen, van der M.K.

    2011-01-01

    In this study we examined ecosystem respiration (RECO) data from 104 sites belonging to FLUXNET, the global network of eddy covariance flux measurements. The goal was to identify the main factors involved in the variability of RECO: temporally and between sites as affected by climate, vegetation str

  13. School climate and delinquency among Chinese adolescents: analyses of effortful control as a moderator and deviant peer affiliation as a mediator.

    Science.gov (United States)

    Bao, Zhenzhou; Li, Dongping; Zhang, Wei; Wang, Yanhui

    2015-01-01

    School climate is the quality and character of school life and reflects the norms, goals, values, interpersonal relationships, teaching and learning practices, and the organizational structure of a school. There is substantial literature documenting the negative association between positive school climate and adolescent delinquency, but little is known about the moderating and mediating mechanisms underlying this relationship. The aim of this study was to examine whether the direct and indirect pathways between school climate and adolescent delinquency would be moderated by effortful control. A sample of 2,758 Chinese adolescents (M age = 13.53 years, SD = 1.06) from 10 middle schools completed anonymous questionnaires regarding school climate, effortful control, deviant peer affiliation, and delinquency. After gender, age, geographical area, and socioeconomic status were included as covariates, the results revealed that school climate was significantly associated with adolescent delinquent behavior. This direct association was moderated by effortful control, such that the negative relationship between positive school climate and delinquency was only significant among adolescents low in effortful control. Moreover, the indirect association between school climate and delinquency via deviant peer affiliation was also moderated by effortful control. Specifically, the moderating effect of effortful control was not only manifested in the relationship between school climate and deviant peer affiliation, but also in the relationship between deviant peer affiliation and delinquency. These findings contribute to understanding the mechanisms through which positive school climate might reduce delinquent behavior and have important implications for prevention efforts aimed at diminishing adolescent delinquency.

  14. Factors controlling spatial variability of DOC concentrations in soil solution at European level

    Science.gov (United States)

    Camino Serrano, Marta; Janssens, Ivan; Luyssaert, Sebastiaan; Gielen, Bert; Guenet, Bertrand; De Vos, Bruno; Ciais, Philippe

    2013-04-01

    The lateral transport of dissolved organic carbon (DOC) is an important and not well-understood process linking terrestrial and aquatic ecosystems. Up to day very few Earth System Models (ESMs) represent explicitly this process despite its crucial role in the global carbon cycle. However, to be able to integrate DOC leaching in ESMs, more accurate information is needed in order to better understand and predict DOC dynamics. DOC concentrations mainly vary by geographical location, soil and vegetation types, topography, season and climate. Within this framework, a database was designed to compile data on DOC in soil solution at different depths in different ecosystems around the world, with special focus on European sites. The database contains information on 349 sites, with 304 being forest, gathered from published literature and datasets accessible on the internet. A substantial dataset was provided by International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests). The database also includes other meta-data related to the sites, such as land cover, soil properties, climate, annual water balance and other soil solution parameters. The analysis of the database has been focused on: 1) the study of the environmental and physical factors that are acting as drivers of DOC concentrations changes in soil solution across sites at European level , and 2) the DOC distribution through the soil profile and how this varies with different vegetation types and soil properties. The preliminary results show that variables related to biological processes (Dry weight of the organic layer, for example) are the most important in explaining the spatial distribution of the DOC concentration in soil solution at the European scale. However, the interactions between variables are complex and we will need further analysis in order to draw more robust conclusions. With regards to the vertical profile of DOC, we found that there is a

  15. Control factors of partial nitritation for landfill leachate treatment

    Institute of Scientific and Technical Information of China (English)

    LIANG Zhu; LIU Jun-xin

    2007-01-01

    Anaerobic ammonium oxidation (ANAMMOX) technology has potential technical superiority and economical efficiency for the nitrogen removal from landfill leachate, which contains high-strength ammonium nitrogen (NH4+-N) and refractory organics. To complete the ANAMMOX process, a preceding partial nitritation step to produce the appropriate ratio of nitrite/ammonium is a key stage. The objective of this study was to determine the optimal conditions to acquire constant partial nitritation for landfill leachate treatment, and a bench scale fixed bed bio-film reactor was used in this study to investigate the effects of the running factors on the partial nitritation. The results showed that both the dissolved oxygen (DO) concentration and the ammonium volumetric loading rate (Nv) had effects on the partial nitritation. In the controlling conditions with a temperature of 30±1℃, Nv of 0.2-1.0 kg NH4+-N/(m3·d), and DO concentration of 0.8-2.3 mg/L, the steady partial nitritation was achieved as follows: more than 94% partial nitritation efficiency (nitrite as the main product), 60%-74% NH4+-N removal efficiency, and NO2--N/NH4+-N ratio (concentration ratio) of 1.0-1.4 in the effluent.The impact of temperature was related to Nv at certain DO concentration, and the temperature range of 25-30℃ was suitable for treating high strength ammonium leachate. Ammonium-oxidizing bacteria (AOB) could be acclimated to higher FA (free ammonium) in the range of 122-224 mg/L. According to the denaturing gradient gel electrophoresis analysis result of the bio-film in the reactor, there were 25 kinds of 16S rRNA gene fragments, which indicated that abundant microbial communities existed in the bio-film, although high concentrations of ammonium and FA may inhibit the growth of the nitrite-oxidizing bacteria (NOB) and other microorganisms in the reactor.

  16. An analysis of factors that lead to better learning in an integrated and interdisciplinary course on climate change

    Science.gov (United States)

    Reed, D. E.; Lyford, M.; Schmidt, L. O.; Bowles-Terry, M.

    2012-12-01

    Climate change education presents many challenges to college educators due to the interdisciplinary nature of the issue as well as the social and political context and implications. This presents multiple barriers to learning for the student, both because it is difficult to address all scientific components in one course, and because many students have strong preconceived feelings or beliefs about climate change. A further barrier to learning for non-science majors is that very often the number of required science courses is low and a highly complex issue such as climate change is difficult to address in introductory science courses. To attempt to address these issues a course for non-science majors, Life Science 1002, Discovering Science, at the University of Wyoming was created as an interdisciplinary and integrated science course that includes a lecture component as well as weekly lab and discussion sections. Our previous work has shown a clear change in the reference sources used by non-science majors when referring to complex topics; namely, students increase their use of scientific journals when they are shown how to use scientific journals and students also report a correlated decrease in non-peer reviewed sources (ie, radio, newspapers, TV). We seek to expand on this work by using pre- and post-topic student surveys in the course at the University of Wyoming to directly measure student performance in different components of the course. The course has enrollment between 120 and 130 students, with nearly equal distribution between grade levels and a wide sampling of non-science majors or undeclared majors. For this work we will use a non-quantitative survey of students to find out which part of the course (lecture, lab or discussion) is most effective for student learning. Further, quantitative analysis of which factors of the student body (class standing, major, gender, background and personal beliefs) will be correlated to help predict who achieved the best

  17. A model of relationship between climate and soil factors related to oxalate content in porang (Amorphophallus muelleri Blume corm

    Directory of Open Access Journals (Sweden)

    SERAFINAH INDRIYANI

    2011-01-01

    Full Text Available Indriyani S, Arisoesilaningsih E, Wardiyati T, Purnobasuki H (2011 A model of relationship between climate and soil factors related to oxalate content in porang (Amorphophallus muelleri Blume corm. Biodiversitas 12: 45-51. The abiotic environment as well as the biotic environment, involved climate and soil affect directly or indirectly to plant growth as well as plant substance. The objective of the research was to obtain a model of relationship between climate and soil factors related to oxalate content in porang corm. Porang corms were collected from five locations of porang agroforestry in East Java. The locations were (i Klangon Village, Saradan Subdistrict, Madiun District; (ii Klino Villlage, Sekar Subdistrict, Bojonegoro District; (iii Bendoasri Village, Rejoso Subdistrict, Nganjuk District; (iv Sugihwaras Village, Nggluyu Subdistrict, Nganjuk District and (v Kalirejo Village, Kalipare Subdistrict, Malang District. Geography variable consist of altitude. Climate variables consist of percentage of radiation, temperature and rainfall. Soil variables consist of electrical conductivity, pH, soil specific gravity, soil organic matter, available of calcium, and cation exchange capacity (CEC. Vegetation variables consist of species of plant tree and percentage of coverage. Porang vegetative growth variables consist of plant height, number of bulbil, canopy diameter, and petiole diameter. Corm variables consist of corm diameter, corm weight, and corm specific gravity. Oxalate variables consist of total oxalate, soluble oxalate, insoluble oxalate, and density of calcium oxalate crystal. Oxalate contents were measured based on AOAC method. All of variables were collected from first to fourth growth period of porang. Data were analyzed by smartPLS (Partial Least Square software. The results showed that there were significantly direct effect between altitude and temperature, altitude and CEC of soil, temperature and CEC of soil, altitude and

  18. Korean Early Childhood Educators' Multi-Dimensional Teacher Self-Efficacy and ECE Center Climate and Depression Severity in Teachers as Contributing Factors

    Science.gov (United States)

    Kim, Yeon Ha; Kim, Yang Eun

    2010-01-01

    This study investigated profiles of South Korean early childhood educators' teacher self-efficacy and contributing factors to teacher self-efficacy. The contributing factors were examined with a focus on early childhood education (ECE) center climate and depression severity in teachers as well as teacher and classroom characteristics. The results…

  19. Internal Flow Management in a Multi-Zone Climate Control Unit

    NARCIS (Netherlands)

    Persis, C. De; Jessen, J.J.; Izadi-Zamanabadi, R.; Schiøler, H.

    2006-01-01

    In this contribution, we examine a dynamic model describing the evolution of internal climate conditions in a closed environment partitioned into zones for which different climate conditions must be guaranteed. The zones are not separated, large air masses are exchanged among them, and the behavior

  20. Early Eocene hyperthermals record orbitally controlled changes in high latitude climates

    Science.gov (United States)

    Galeotti, S.; DeConto, R. M.; Lanci, L.; Pagani, M.; Rohl, U.; Westerhold, T.; Zachos, J. C.

    2012-04-01

    The Late Paleocene to Early Eocene records a succession of short-term (104 yr) negative carbon isotope excursions (CIEs) in marine carbonates and organic carbon. Available data indicate that at least three of these episodes, including the Paleocene Eocene Thermal Maximum (PETM) at ca. 55.5, the Eocene Thermal Maximum (ETM)2 at ca. 53.5 Ma and the ETM3 at ca. 52 Ma, were associated with rapid warming, and widespread marine carbonate dissolution forced by shoaling of the carbonate lysocline and lowering of the carbonate saturation state. Large temperature raises associated with decreased δ13C values in both terrestrial and oceanic records and concomitant acidification of oceanic waters implies that hyperthermals were caused by the addition of massive amounts of 13C-depleted greenhouse gases (CH4 and/or CO-2) into the atmosphere and subsequent sequestration by oceanic waters. Cyclostratigraphic analyses of marine sequences provided evidence that CIEs and associated carbonate dissolution episodes were linked to orbital changes in insolation. Here we show grounds that Early Eocene hyperthermals are part of a continuum of δ13C anomaly and carbonate dissolution episodes and are triggered by long-term orbitally-controlled changes in local climates at high latitudes.

  1. Winter climate controls soil carbon dynamics during summer in boreal forests

    International Nuclear Information System (INIS)

    Boreal forests, characterized by distinct winter seasons, store a large proportion of the global terrestrial carbon (C) pool. We studied summer soil C-dynamics in a boreal forest in northern Sweden using a seven-year experimental manipulation of soil frost. We found that winter soil climate conditions play a major role in controlling the dissolution/mineralization of soil organic-C in the following summer season. Intensified soil frost led to significantly higher concentrations of dissolved organic carbon (DOC). Intensified soil frost also led to higher rates of basal heterotrophic CO2 production in surface soil samples. However, frost-induced decline in the in situ soil CO2 concentrations in summer suggests a substantial decline in root and/or plant associated rhizosphere CO2 production, which overrides the effects of increased heterotrophic CO2 production. Thus, colder winter soils, as a result of reduced snow cover, can substantially alter C-dynamics in boreal forests by reducing summer soil CO2 efflux, and increasing DOC losses. (letter)

  2. Lifestyle factors and reproductive health: taking control of your fertility

    OpenAIRE

    Sharma, Rakesh; Biedenharn, Kelly R; Fedor, Jennifer M; Agarwal, Ashok

    2013-01-01

    Approximately 10 to 15% of couples are impacted by infertility. Recently, the pivotal role that lifestyle factors play in the development of infertility has generated a considerable amount of interest. Lifestyle factors are the modifiable habits and ways of life that can greatly influence overall health and well-being, including fertility. Many lifestyle factors such as the age at which to start a family, nutrition, weight, exercise, psychological stress, environmental and occupational exposu...

  3. Climatic Conditions, Cultural Diversity, and Labor Productivity

    OpenAIRE

    Gundlach, Erich; Matus-Velasco, Ximena

    2000-01-01

    Countries with the highest labor productivity overwhelmingly lie in the world's temperate climatic zones far away from the equator. The question we address is whether climatic conditions as measured by distance from the equator remain correlated with labor productivity after other variables are taken into account. We find that climatic conditions do not have a significant impact on labor productivity once we control for factor accumulation and cultural diversity within countries. Our regressi...

  4. Climate change and larval transport in the ocean: fractional effects from physical and physiological factors.

    Science.gov (United States)

    Kendall, Matthew S; Poti, Matt; Karnauskas, Kristopher B

    2016-04-01

    Changes in larval import, export, and self-seeding will affect the resilience of coral reef ecosystems. Climate change will alter the ocean currents that transport larvae and also increase sea surface temperatures (SST), hastening development, and shortening larval durations. Here, we use transport simulations to estimate future larval connectivity due to: (1) physical transport of larvae from altered circulation alone, and (2) the combined effects of altered currents plus physiological response to warming. Virtual larvae from islands throughout Micronesia were moved according to present-day and future ocean circulation models. The Hybrid Coordinate Ocean Model (HYCOM) spanning 2004-2012 represented present-day currents. For future currents, we altered HYCOM using analysis from the National Center for Atmospheric Research Community Earth System Model, version 1-Biogeochemistry, Representative Concentration Pathway 8.5 experiment. Based on the NCAR model, regional SST is estimated to rise 2.74 °C which corresponds to a ~17% decline in larval duration for some taxa. This reduction was the basis for a separate set of simulations. Results predict an increase in self-seeding in 100 years such that 62-76% of islands experienced increased self-seeding, there was an average domainwide increase of ~1-3% points in self-seeding, and increases of up to 25% points for several individual islands. When changed currents alone were considered, approximately half (i.e., random) of all island pairs experienced decreased connectivity but when reduced PLD was added as an effect, ~65% of connections were weakened. Orientation of archipelagos relative to currents determined the directional bias in connectivity changes. There was no universal relationship between climate change and connectivity applicable to all taxa and settings. Islands that presently export large numbers of larvae but that also maintain or enhance this role into the future should be the focus of conservation

  5. Cosmic Rays and Solar Insolation as the Main Control Parameters of the Catastrophe Theory of Climatic Response to Orbital Variations

    CERN Document Server

    Rusov, V D; Vaschenko, V N; Pavlovich, V N; Zelentsova, T N; Mihalus, O T; Tarasov, V A; Saranuk, D N

    2004-01-01

    The energy-balance model of global climate, which is taking into account a nontrivial role of solar and galactic protons, is presented. The model is described by the equation of fold catastrophe relative to increment of temperature, where the variation of a solar insolation and cosmic rays are control parameters. It is shown that the bifurcation equation of the model describes one of two stable states of the climate system. The solution of this equation exhibits the property of the determined bistable behavior of climate at the global level and the possibility of appearance of the determined chaos of "the weathers" at the local levels. The results of the comparative analysis of the computer simulation of the time-dependent solution of energy-balance model of global climate and the oxygen isotope records for deep-sea core V28-238 over the past 730 kyr are presented, and the evolution of climate on 100 kyr forward is also predicted. It is shown that the proposed model successfully explains the nicety of the pal...

  6. Dynamics of the Coupled Human-climate System Resulting from Closed-loop Control of Solar Geoengineering

    Energy Technology Data Exchange (ETDEWEB)

    MacMartin, Douglas; Kravitz, Benjamin S.; Keith, David; Jarvis, Andrew

    2014-07-08

    If solar radiation management (SRM) were ever implemented, feedback of the observed climate state might be used to adjust the radiative forcing of SRM, in order to compensate for uncertainty in either the forcing or the climate response; this would also compensate for unexpected changes in the system, e.g. a nonlinear change in climate sensitivity. This feedback creates an emergent coupled human-climate system, with entirely new dynamics. In addition to the intended response to greenhouse-gas induced changes, the use of feedback would also result in a geoengineering response to natural climate variability. We use a simple box-diffusion dynamic model to understand how changing feedback-control parameters and time delay affect the behavior of this coupled natural-human system, and verify these predictions using the HadCM3L general circulation model. In particular, some amplification of natural variability is unavoidable; any time delay (e.g., to average out natural variability, or due to decision-making) exacerbates this amplification, with oscillatory behavior possible if there is a desire for rapid correction (high feedback gain), but a delayed response needed for decision making. Conversely, the need for feedback to compensate for uncertainty, combined with a desire to avoid excessive amplification, results in a limit on how rapidly SRM could respond to uncertain changes.

  7. Improving PAQ and comfort conditions in Spanish office buildings with passive climate control

    Energy Technology Data Exchange (ETDEWEB)

    Orosa, Jose A.; Baalina, A. [Departamento de Energia y P.M. Escuela Tecnica Superior de N. y M, Universidade da Coruna, Paseo de Ronda 51, P.C.:15011 A Coruna (Spain)

    2009-03-15

    Some researchers have demonstrated that passive moisture transfer between indoor air and hygroscopic structures has the potential to moderate variations of indoor air relative humidity and, thus, to improve comfort and PAQ [Simonson CJ, Salonvaara M, Ojalen T. The effect of structures on indoor humidity-possibility to improve comfort and perceived air quality. Indoor Air 2002; 12: 243-51; Simonson CJ, Salonvaara M, Ojalen T. Improving indoor climate and comfort with wooden structures. Espoo 2001. Technical Research Centre of Finland, VTT Publications 431.200p+app 91p]. The main objective of this study is to show the internal wall coating effect on indoor air conditions and, as a consequence of this, in comfort conditions and PAQ. In a previous paper [Orosa JA, Baalina A. Passive climate control in Spanish office buildings for long periods of time. Building and Environment 2008], we analysed the influence of permeable and impermeable materials on indoor air conditions, during the unoccupied period, in 25 office buildings in different seasons. Results obtained lead us to conclude that real coverings such as permeable, semi-permeable and impermeable types, present different behavioural patterns in indoor air conditions. Furthermore, we concluded that an absorbent structure will moderate relative humidity indoors. In this paper, we study this indoor relative humidity effect on local thermal discomfort, due to decreased respiratory cooling, and indoor ambience acceptability for the early hours of morning applying PD and Acc models [Toftum J, Jorgensen AS, Fanger PO. Upper limits for indoor air humidity to avoid uncomfortably humid skin. Energy and buildings 1998; 28: 1-13; Toftum J, Jorgensen AS, Fanger PO. Upper limits of air humidity for preventing warm respiratory discomfort. Energy and Buildings 1998; 28: 15-23] such as that proposed by Simonson et al. [The effect of structures on indoor humidity-possibility to improve comfort and perceived air quality. Indoor Air

  8. The Relationship Between Monthdisease Incidence Rate and Climatic Factor of Classical Swine Fever

    Science.gov (United States)

    Wang, Hongbin; Xu, Danning; Xiao, Jianhua; Zhang, Ru; Dong, Jing

    The Swine Fever is a kind of acute, highly infective epidemic disease of animals; it is name as Classical Swine Fever (CSF) by World animal Health organization. Meteorological factors such as temperature, air pressure and rainfall affect the epidemic of CSF significantly through intermediary agent and CSF viral directly. However there is significant difference among different region for mode of effects. Accordingly, the analyze must adopt different methods. The dependability between incidence rate each month of CSF and meteorological factors from 1999 to 2004 was analyzed in this paper. The function of meteorological factors on CSF was explored and internal law was expected to be discovered. The correlation between the incidence rate of Swine Fever and meteorological factors, thus the foundation analysis of the early warning and the decision-making was made, the result indicated that the incidence rate of CSF has negative correlation with temperature, rainfall, cloudage; relative humidity has positive correlation with disease; for air pressure, except average air pressure of one month, other air pressure factors have positive correlation with disease; for wind speed, except Difference among moths of wind speed and average temperature of one month. have positive correlation with disease, other wind speed factors has negative correlation with disease.

  9. Digital infrared thermography of the scrotum, semen quality, serum testosterone levels in Nellore bulls (Bos taurus indicus) and their correlation with climatic factors

    OpenAIRE

    Felipe Rydygier de Ruediger; Marcelo George Mungai Chacur; Francisco Carlos Platzeck Estrella Alves; Eunice Oba; Alcides de Amorim Ramos

    2016-01-01

    The objective was to study the relationship of climatic conditions with the temperature of the scrotum surface and sperm quality through digital infrared thermography in Nellore bulls, raised extensively. In six bulls held with scrotal thermography Flir E40® cameras, blood samples for serum testosterone and semen collection were taken by electroejaculation every 10 days, with six replications. Climatic factors: ambient temperature, relative humidity, dry globe temperature and temperature of t...

  10. Reactive current control through SVC for load power factor correction

    Energy Technology Data Exchange (ETDEWEB)

    Kodsi, Sameh K.M.; Canizares, Claudio A.; Kazerani, Mehrdad [University of Waterloo, Department of Electrical & amp; Computer Engineering, Waterloo, Ont. (Canada N2L 3G1)

    2006-06-15

    This paper discusses a new technique for controlling SVCs (Fixed Capacitor-Thyristor Controlled Reactor) in power systems with the aim of canceling the reactive current component of the load. A complete model of the SVC with its control circuit is set up and simulated in the EMTDC program. The generated harmonics from the proposed SVC controller are considered to design simple tuned filters to cancel the undesirable harmonic components. The effect of these filters is considered as well in the SVC control design, so that the reactive current component absorbed by the combination of the load, SVC, and filters is eliminated. The proposed control technique is compared with respect to a standard PI-based SVC controller. (author)

  11. Factors affecting population dynamics of leaf beetles in a subarctic region: The interplay between climate warming and pollution decline.

    Science.gov (United States)

    Zvereva, Elena L; Hunter, Mark D; Zverev, Vitali; Kozlov, Mikhail V

    2016-10-01

    Understanding the mechanisms by which abiotic drivers, such as climate and pollution, influence population dynamics of animals is important for our ability to predict the population trajectories of individual species under different global change scenarios. We monitored four leaf beetle species (Coleoptera: Chrysomelidae) feeding on willows (Salix spp.) in 13 sites along a pollution gradient in subarctic forests of north-western Russia from 1993 to 2014. During a subset of years, we also measured the impacts of natural enemies and host plant quality on the performance of one of these species, Chrysomela lapponica. Spring and fall temperatures increased by 2.5-3°C during the 21-year observation period, while emissions of sulfur dioxide and heavy metals from the nickel-copper smelter at Monchegorsk decreased fivefold. However, contrary to predictions of increasing herbivory with climate warming, and in spite of discovered increase in host plant quality with increase in temperatures, none of the beetle species became more abundant during the past 20years. No directional trends were observed in densities of either Phratora vitellinae or Plagiodera versicolora, whereas densities of both C. lapponica and Gonioctena pallida showed a simultaneous rapid 20-fold decline in the early 2000s, remaining at very low levels thereafter. Time series analysis and model selection indicated that these abrupt population declines were associated with decreases in aerial emissions from the smelter. Observed declines in the population densities of C. lapponica can be explained by increases in mortality from natural enemies due to the combined action of climate warming and declining pollution. This pattern suggests that at least in some tri-trophic systems, top-down factors override bottom-up effects and govern the impacts of environmental changes on insect herbivores. PMID:27266523

  12. Factors affecting population dynamics of leaf beetles in a subarctic region: The interplay between climate warming and pollution decline.

    Science.gov (United States)

    Zvereva, Elena L; Hunter, Mark D; Zverev, Vitali; Kozlov, Mikhail V

    2016-10-01

    Understanding the mechanisms by which abiotic drivers, such as climate and pollution, influence population dynamics of animals is important for our ability to predict the population trajectories of individual species under different global change scenarios. We monitored four leaf beetle species (Coleoptera: Chrysomelidae) feeding on willows (Salix spp.) in 13 sites along a pollution gradient in subarctic forests of north-western Russia from 1993 to 2014. During a subset of years, we also measured the impacts of natural enemies and host plant quality on the performance of one of these species, Chrysomela lapponica. Spring and fall temperatures increased by 2.5-3°C during the 21-year observation period, while emissions of sulfur dioxide and heavy metals from the nickel-copper smelter at Monchegorsk decreased fivefold. However, contrary to predictions of increasing herbivory with climate warming, and in spite of discovered increase in host plant quality with increase in temperatures, none of the beetle species became more abundant during the past 20years. No directional trends were observed in densities of either Phratora vitellinae or Plagiodera versicolora, whereas densities of both C. lapponica and Gonioctena pallida showed a simultaneous rapid 20-fold decline in the early 2000s, remaining at very low levels thereafter. Time series analysis and model selection indicated that these abrupt population declines were associated with decreases in aerial emissions from the smelter. Observed declines in the population densities of C. lapponica can be explained by increases in mortality from natural enemies due to the combined action of climate warming and declining pollution. This pattern suggests that at least in some tri-trophic systems, top-down factors override bottom-up effects and govern the impacts of environmental changes on insect herbivores.

  13. Factors controlling gully erosion at different spatial and temporal scales in rangelands of SW Spain

    Science.gov (United States)

    Gómez Gutiérrez, Á.; Schnabel, S.; Lavado Contador, J. F.; Pulido Fernández, M.

    2009-04-01

    Mediterranean climate with Atlantic influences. Results showed that at the catchment scale, and for a short period (1-10 years), rainfall and soil moisture were the most important factors controlling gully erosion rates. In fact, gully erosion was highly related with the rainfall amount (r=0,90), with the number of times event discharge exceeded 1000 cubic meters (r=0,76) and with the number of times peak discharge exceeded 100 l/s (r=0,72). However, when the temporal scale was extended to several decades (from 1945 to 2006), land use and vegetation cover (specially the extension of cultivated area and livestock density) proved to be the most important factors determining the area affected by gullying. With respect to the spatial variation of gullying at the regional scale, the model results indicate lithology as being the most important variable, followed by vegetation structure and summer rainfall. This model was able to explain a large portion of the spatial distribution of gullies at the regional scale. Concluding, at different spatial and temporal scales the importance of factors which determine gully erosion intensity, extension and rates varies notably. At the short-term rainfall and runoff dynamics and the moisture content of the sediments are the dominant factors, whereas at the medium-term land use and vegetation cover become more important. At the regional scale lithology and vegetation turned out to be the dominant factors in determining the location of areas susceptible to gully erosion in rangelands of Extremadura.

  14. Local control on precipitation in a fully coupled climate-hydrology model.

    Science.gov (United States)

    Larsen, Morten A D; Christensen, Jens H; Drews, Martin; Butts, Michael B; Refsgaard, Jens C

    2016-01-01

    The ability to simulate regional precipitation realistically by climate models is essential to understand and adapt to climate change. Due to the complexity of associated processes, particularly at unresolved temporal and spatial scales this continues to be a major challenge. As a result, climate simulations of precipitation often exhibit substantial biases that affect the reliability of future projections. Here we demonstrate how a regional climate model (RCM) coupled to a distributed hydrological catchment model that fully integrates water and energy fluxes between the subsurface, land surface, plant cover and the atmosphere, enables a realistic representation of local precipitation. Substantial improvements in simulated precipitation dynamics on seasonal and longer time scales is seen for a simulation period of six years and can be attributed to a more complete treatment of hydrological sub-surface processes including groundwater and moisture feedback. A high degree of local influence on the atmosphere suggests that coupled climate-hydrology models have a potential for improving climate projections and the results further indicate a diminished need for bias correction in climate-hydrology impact studies. PMID:26960564

  15. What controls vulnerability of watersheds to climate and land use change across the United States?

    Science.gov (United States)

    Singh, R.; Deshmukh, A.

    2015-12-01

    Understanding the response of watersheds to climate and land use change is crucial for management of water resources. However, obtaining reliable projections of water resources remains a challenge in the wake of large uncertainties in projections of climate and land use change. Thus, alternative assessment criteria independent of projections of climate and land use change would be useful in providing decision makers with an approximate evaluation of vulnerability of a watershed to change. Here, we present an analysis to ascertain the vulnerability of watersheds to climate and land use change independent of future projections. Using a recently developed bottom up approach, we first identify critical thresholds of climate and land use change across 78 watersheds of United States. Then, we explore the relationship between critical climate thresholds and watershed characteristics to identify characteristics that are correlated to these thresholds. We perform this analysis for various streamflow indicators that capture the magnitude, frequency, and duration of flows. We find significant negative correlation between soil properties like average percentage sand and critical threshold of precipitation change causing vulnerability of indicator representing water availability - mean annual streamflow. This indicates that higher amounts of sand content in soils may be related with reduced vulnerability to climatic changes. We also find significant positive correlation between urban land use and critical threshold of precipitation change across the watersheds for mean annual streamflow. This suggests that watersheds with higher urban land use may be more vulnerable to precipitation change.

  16. Local control on precipitation in a fully coupled climate-hydrology model.

    Science.gov (United States)

    Larsen, Morten A D; Christensen, Jens H; Drews, Martin; Butts, Michael B; Refsgaard, Jens C

    2016-01-01

    The ability to simulate regional precipitation realistically by climate models is essential to understand and adapt to climate change. Due to the complexity of associated processes, particularly at unresolved temporal and spatial scales this continues to be a major challenge. As a result, climate simulations of precipitation often exhibit substantial biases that affect the reliability of future projections. Here we demonstrate how a regional climate model (RCM) coupled to a distributed hydrological catchment model that fully integrates water and energy fluxes between the subsurface, land surface, plant cover and the atmosphere, enables a realistic representation of local precipitation. Substantial improvements in simulated precipitation dynamics on seasonal and longer time scales is seen for a simulation period of six years and can be attributed to a more complete treatment of hydrological sub-surface processes including groundwater and moisture feedback. A high degree of local influence on the atmosphere suggests that coupled climate-hydrology models have a potential for improving climate projections and the results further indicate a diminished need for bias correction in climate-hydrology impact studies.

  17. Regional climate signal modified by local factors - multi core study records (Lake Czechowskie region, N Poland)

    Science.gov (United States)

    Zawiska, Izabela; Rzodkiewicz, Monika; Noryśkiewicz, Agnieszka; Kramkowski, Mateusz; Obremska, Milena; Ott, Florian; Plessen, Birgit; Tjallingii, Rik; Słowiński, Michał; Błaszkiewicz, Mirosław; Brauer, Achim

    2016-04-01

    Lake sediments can be utilized as valuable paleoclimate and environmental archives as they contain information of past changes. Multi-proxy analyses of sedimentary compartments (e.g. pollen, diatoms, Cladocera) reveal those changes. However, to decipher the spatial variability of past climate changes and to define the proxies suited for local and regional scale reconstructions archive comparisons are needed. Here we present a detailed multi-proxy study from four different sediment cores covering the Younger Dryas cold period from the Lake Czechowskie region (N Poland). Three cores are located along a transect in the Lake Czechowskie basin from its deepest point towards a former lake bay close to today's shoreline. The fourth lacustrine sediment core was retrieved from the Trzechowskie paleolake, app. 1 km W from Lake Czechowskie. The dataset comprises information from pollen (AP, NAP, Juniperus, Betula-tree, Pinus silvestris), diatom (planktonic/benthic index, diatom valve concentration, dominant species), Cladocera (planktonic/benthic index, dominant species, number of Cladocera species, total sum of specimens) and geochemical (TOC and CaCO3 content, mineral matter, titanium) analyses. At the beginning of the Younger Dryas the AP pollen share decreased and NAP and Juniperus pollen increased in all studied locations. The mineral matter and titanium record showed higher values in two cores taken from the deepest parts of Lake Czechowskie and the core from Trzechowskie paleolake while in the core located at the marginal part of the lake it was already high in Allerød and it did not change much in Younger Dryas. The Cladocera based indexes: total sum of specimens and number of species decreased at the beginning of YD but on the contrary the Cladocera species composition changes were site-specific. The diatoms valve concentration index significantly lowered in core from the deep location while on the contrary increased in core from paleolake Trzechowskie. Our results

  18. Investigating the effective factors on management internal controls applying

    Directory of Open Access Journals (Sweden)

    Ahmad Ahmadkhani

    2012-08-01

    Full Text Available Information technology plays an important role on increasing internal control in many organizations. In this paper, we present an empirical study to measure the impact of information technology, hiring high quality skilled management team, using high quality standards and increasing employees' awareness on managing internal control. The survey uses a questionnaire based on Likert scale and distributes among the people who work in either administration or financial sectors of governmental agencies in province of Zanjan, Iran. The results of the study indicate that the implementation of information technology positively influences management team to control their system, more effectively, using more skilled and specialized managers positively influences management internal control, an organization with suitable standard positively influences management internal control and increasing employees' awareness positively influences management internal control.

  19. Climate change

    International Nuclear Information System (INIS)

    Based on contributions on 120 French and foreign scientists representing different disciplines (mathematics, physics, mechanics, chemistry, biology, medicine, and so on), this report proposes an overview of the scientific knowledge and debate about climate change. It discusses the various indicators of climate evolution (temperatures, ice surfaces, sea level, biological indicators) and the various factors which may contribute to climate evolution (greenhouse gases, solar radiation). It also comments climate evolutions in the past as they can be investigated through some geological, thermal or geochemical indicators. Then, the authors describe and discuss the various climate mechanisms: solar activity, oceans, ice caps, greenhouse gases. In a third part, the authors discuss the different types of climate models which differ by the way they describe processes, and the current validation process for these models

  20. REPRODUCTIVE FACTORS AND COLORECTAL CANCER RISK. Case - control study.

    OpenAIRE

    Adriana Ruseva; Radka Lazarova; Ilko Kosturkov; Vesselina Ianachkova; Stella Yordanova; Zhivka Boneva; Diana Nikolovska

    2015-01-01

    Colorectal cancer is one of the most common cancers worldwide. The role of the female sex hormones in the etiology of the disease is very intriguing. Reproductive factors are surrogate measure of lifetime exposition to the sex hormones. Purpose: Our aim is to investigate the association between the reproductive factors and colorectal carcinoma risk. Materials and methods: We include 234 Bulgarian women in our study – 117 cases with colorectal cancer and the same number of healthy contr...

  1. Role of Boreal Vegetation in Controlling Ecosystem Processes and Feedbacks to Climate

    Science.gov (United States)

    Chapin, F. S., III; Hooper, D. U.; Hobbie, S. E.; Verville, J. H.

    1997-01-01

    In the field, dark respiration rates are greatest in cores from more northerly locations. This is due in part to greater amounts of dwarf shrub biomass in the more northerly cores, but also to differences in soil organic matter quality. Laboratory incubations of these soils under common conditions show some evidence for greater pools of available carbon in soils from more northerly tundra sites, although the most northerly site does not fit this pattern for reasons which are unclear at this time. While field measurements of cores transplanted among different vegetation types at the same location (Toolik Lake) show relatively small differences in whole ecosystem carbon flux, laboratory incubation of these same soils shows that there are large differences in soil respiration rates under common conditions. This is presumably due to differences in organic matter quality. Microenvironmental site factors (temperature, soil moisture, degree of anaerobiosis, etc.) may be responsible for evening out these differences in the field. These site factors, which differ with slope, aspect, and drainage within a given location along the latitudinal gradient, appear to exert at least as strong a control over carbon fluxes as do macroclimatic factors among sites across the latitudinal gradient. While our field measurements indicate that, in the short term, warming will tend to increase ecosystem losses Of CO2 via respiration more than they will increase plant gross assimilation, the degree to which different topographically-defined plant communities will respond is likely to vary.

  2. Higher Order Factor Structure of a Self-Control Test: Evidence from Confirmatory Factor Analysis with Polychoric Correlations.

    Science.gov (United States)

    Flora, David B.; Finkel, Eli J.; Foshee, Vangie A.

    2003-01-01

    Studied the higher order factor structure of a self-control test developed by H. Grasmick and others (1993). Results for 1,966 eighth and ninth graders show that the self-control test may provide more valid measurement of the constructs it was designed to measure than previous research suggested. (SLD)

  3. Influence of Climate Change and Meteorological Factors on Houston’s Air Pollution: Ozone a Case Study

    Directory of Open Access Journals (Sweden)

    Lei Liu

    2015-05-01

    Full Text Available We examined the past 23 years of ground-level O3 data and selected meteorological parameters in Houston, Texas, which historically has been one of the most polluted cities in the United States. Both 1-h and 8-h O3 exceedances have been reduced significantly down to single digit yearly occurrences. We also found that the frequency of southerly flow has increased by a factor of ~2.5 over the period 1990–2013, likely suppressing O3 photochemistry and leading to a “cleaner” Houston environment. The sea breeze was enhanced greatly from 1990 to 2013 due to increasing land surface temperatures, increased pressure gradients, and slightly stronger on-shore winds. These patterns driven by climate change produce a strengthening of the sea breeze, which should be a general result at locations worldwide.

  4. Other Factors That Affect Heart Disease: Birth Control Pills

    Science.gov (United States)

    ... you are now taking any kind of birth control pill or are considering using one, keep these guidelines in mind: Don't mix smoking and "the pill." If you smoke cigarettes, make a serious effort to quit. If you cannot quit, choose ... of birth control. Cigarette smoking boosts the risk of serious health ...

  5. Digital infrared thermography of the scrotum, semen quality, serum testosterone levels in Nellore bulls (Bos taurus indicus and their correlation with climatic factors

    Directory of Open Access Journals (Sweden)

    Felipe Rydygier de Ruediger

    2016-02-01

    Full Text Available The objective was to study the relationship of climatic conditions with the temperature of the scrotum surface and sperm quality through digital infrared thermography in Nellore bulls, raised extensively. In six bulls held with scrotal thermography Flir E40® cameras, blood samples for serum testosterone and semen collection were taken by electroejaculation every 10 days, with six replications. Climatic factors: ambient temperature, relative humidity, dry globe temperature and temperature of the wet globe were recorded using a globe thermometer (InstruTemp®, ITWTG-2000. Thermal images of the scrotum were analyzed with the Flir Tools® software for the temperatures of scrotal surface, the right and left sides of the scrotum lap thirds: dorsal, middle and ventral testicles; and tails of the epididymis. The semen data and thermograms were submitted to ANOVA and Tukey’s test at 5%. Pearson correlation was used for the surface temperatures of the scrotum, rectal temperature, quantitative and qualitative characteristics of semen and climatic factors. There was a positive correlation (P<0.05 for sperm motility x scrotal temperatures; sperm concentration x scrotal temperatures; climatic factors x rectal temperature. There was a negative correlation (P<0.05 between ambient temperature x sperm concentration. It was concluded that the temperature of the scrotum surface and climatic factors, temperature and humidity, influence the quality of semen. Thermography is recommended as a supplementary examination for reproductive evaluation of bulls.

  6. Perceived behavioural control and the role of information on climate change in increasing sustainable travel

    OpenAIRE

    Howarth, C.; Waterson, B.J.; McDonald, M

    2010-01-01

    This paper investigates the extent to which information on climate change can influence travel behaviour. Travel behaviour on the aggregate level is unsustainable; in light of increasing awareness on climate change, the need to substantially reduce emissions from the transport sector is growing. The status of travel behaviour has grown both in terms of its potential to fill the gaps left by technological and political progress as well as the potential longevity and transferability of its impa...

  7. Controls of climate, topography, vegetation, and lithology on drainage density extracted from high resolution topography data

    Science.gov (United States)

    Sangireddy, Harish; Carothers, Richard A.; Stark, Colin P.; Passalacqua, Paola

    2016-06-01

    Mark Melton in 1957 found that climate, basin morphometry, and surficial variables control drainage density (Dd), but differences observed between field surveyed channels and those mapped on topographic contours or blue lines left doubts on these results. Later, several landscape evolution model and observational studies analyzed the behavior of Dd . However, only a few studies have been performed over a large number of landscapes of different characteristics and have relied on high resolution topography data. We revisit Melton's hypothesis by using meter-resolution digital terrain models (DTMs) in 101 subbasins in the USA. We first propose a dimensionless drainage density (Ddd) metric based on the ratio of likely channelized pixels to total number of basin pixels, which has the advantage of eliminating the computation of the channel network. Our analysis shows that Ddd is a weak scaling function of the input DTM resolution compared to the classic dimensional Dd metric (ratio of total channel length to total basin area). We analyze the correlation of Ddd and mean annual precipitation (MAP) with a Gaussian mixture model which identifies two sub-groups displaying different correlation; negative in arid and semi-arid environments, and positive in humid environments. The transition in correlation is around 1100 ± 100 mm/yr of MAP and is accompanied by the occurrence of thick soil layers and high available water capacity that promote dense vegetation cover (Vcov) and low Ddd . While small variation in Ddd is observed across vegetation types, increasing Vcov corresponds to decreasing Ddd . We also explore the relationship between Ddd and relief R, and Ddd and lithology. Ddd and R are weakly correlated in arid and semi-arid environments, while they have strong positive correlation in humid environments. No significant correlation is found between Ddd and lithology although the results are likely affected by our sample choice.

  8. Climatic and geologic controls on suspended sediment flux in the Sutlej River Valley, western Himalaya

    Directory of Open Access Journals (Sweden)

    H. Wulf

    2012-01-01

    Full Text Available The sediment flux through Himalayan rivers directly impacts water quality and is important for sustaining agriculture as well as maintaining drinking-water and hydropower generation. Despite the recent increase in demand for these resources, little is known about the triggers and sources of extreme sediment flux events, which lower water quality and account for extensive hydropower reservoir filling and turbine abrasion. Here, we present a comprehensive analysis of the spatiotemporal trends in suspended sediment flux based on daily data during the past decade (2001–2009 from four sites along the Sutlej River and from four of its main tributaries. In conjunction with satellite data depicting rainfall and snow cover, air temperature, earthquake records, and Schmidt hammer rock strength measurements, we infer climatic and geologic controls of peak suspended sediment concentration (SSC events. Our study identifies three key findings: First, peak SSC events (≥99th SSC percentile coincide frequently (57–80% with heavy rainstorms and account for about 30% of the suspended sediment flux in the semi-arid to arid interior of the orogen. Second, we observe an increase of suspended sediment flux from the Tibetan Plateau to the Himalayan front at mean annual timescales. This sediment-flux gradient suggests that averaged, modern erosion in the western Himalaya is most pronounced at frontal regions, which are characterized by high monsoonal rainfall and thick soil cover. Third, in seven of eight catchments we find an anticlockwise hysteresis loop of annual sediment flux, which appears to be related to enhanced glacial sediment evacuation during late summer. Our analysis emphasizes the importance of unconsolidated sediments in the high-elevation sector that can easily be mobilized by hydrometeorological events and higher glacial-meltwater contributions.

  9. Sleeper Cab Climate Control Load Reduction for Long-Haul Truck Rest Period Idling

    Energy Technology Data Exchange (ETDEWEB)

    Lustbader, J. A.; Kreutzer, C.; Adelman, S.; Yeakel, S.; Zehme, J.

    2015-04-29

    Annual fuel use for long-haul truck rest period idling is estimated at 667 million gallons in the United States. The U.S. Department of Energy’s National Renewable Energy Laboratory’s CoolCab project aims to reduce heating, ventilating, and air conditioning (HVAC) loads and resulting fuel use from rest period idling by working closely with industry to design efficient long-haul truck climate control systems while maintaining occupant comfort. Enhancing the thermal performance of cab/sleepers will enable smaller, lighter, and more cost-effective idle reduction solutions. In order for candidate idle reduction technologies to be implemented at the original equipment manufacturer and fleet level, their effectiveness must be quantified. To address this need, a number of promising candidate technologies were evaluated through experimentation and modeling to determine their effectiveness in reducing rest period HVAC loads. For this study, load reduction strategies were grouped into the focus areas of solar envelope, occupant environment, and conductive pathways. The technologies selected for a complete-cab package of technologies were “ultra-white” paint, advanced insulation, and advanced curtains. To measure the impact of these technologies, a nationally-averaged solar-weighted reflectivity long-haul truck paint color was determined and applied to the baseline test vehicle. Using the complete-cab package of technologies, electrical energy consumption for long-haul truck daytime rest period air conditioning was reduced by at least 35% for summer weather conditions in Colorado. The National Renewable Energy Laboratory's CoolCalc model was then used to extrapolate the performance of the thermal load reduction technologies nationally for 161 major U.S. cities using typical weather conditions for each location over an entire year.

  10. Comparative Study of Evolutionary Multi-objective Optimization Algorithms for a Non-linear Greenhouse Climate Control Problem

    DEFF Research Database (Denmark)

    Ghoreishi, Newsha; Sørensen, Jan Corfixen; Jørgensen, Bo Nørregaard

    2015-01-01

    Non-trivial real world decision-making processes usually involve multiple parties having potentially conflicting interests over a set of issues. State-of-the-art multi-objective evolutionary algorithms (MOEA) are well known to solve this class of complex real-world problems. In this paper, we...... compare the performance of state-of-the-art multi-objective evolutionary algorithms to solve a non-linear multi-objective multi-issue optimisation problem found in Greenhouse climate control. The chosen algorithms in the study includes NSGAII, eNSGAII, eMOEA, PAES, PESAII and SPEAII. The performance...... of all aforementioned algorithms is assessed and compared using performance indicators to evaluate proximity, diversity and consistency. Our insights to this comparative study enhanced our understanding of MOEAs performance in order to solve a non-linear complex climate control problem. The empirical...

  11. Impacts on Power Factor of AC Voltage Controllers Under Non-Sinusoidal Conditions

    Directory of Open Access Journals (Sweden)

    Mukhtiar Ahmed Mahar

    2012-04-01

    Full Text Available AC-AC conversion is obtained with the help of Cyclo-converters, DC Link converters and AC Voltage Controllers. AC voltage controllers are also referred to as voltage regulators. Main issue concerned to these converters is that they generate harmonics due to periodic variable structure system. The generated harmonics create disturbances and degrade the performance of converter. The power factor of supply side is affected due to these harmonics. This paper focuses on source side power factor of ac voltage controllers under nonsinusoidal conditions. In order to observe the power factor, measurement tool of power factor and simulation model of ac voltage controller is also developed in MATLAB software.

  12. CLIMATIC FACTORS AND ESTABLISHMENT OF QUERCUS ILEX - COMMUNITIES IN TRIESTE PROVINCE (NE ITALY

    Directory of Open Access Journals (Sweden)

    A. FURLANETTO

    2004-01-01

    Full Text Available In the coastal area called "Cernizza" (near Duino. ca 15 km NW from Trieste, at an altitude between 0 and 40 m. is located a wood vegetation complex characterized by Quercus ilex and Carpinus orientalis. The bedrocks of this site is carbonatic. This wood vegetation does not occur in other sites or the Trieste province, where deciduous oak woods (Q. pubescells, Q. petraea s.1. are dominant both on arenaceus and on carbonatic rocks. Other Quercus ilex communities are occurring only as scrubs on the calcareous coastal cliffs characterized by primitive lithosoils. In order to detect if this wood community might be an expression of the c1imate dominating this particular zone, some Duino's c1imatic data, relative lo a record period of 9 years. have been compared with the Trieste's ones. The analysed parameters were the following: air temperature. rainfall, evaporation. wind speed and relative humidity. From the comparison of these paramenters it emerged that the Duino's climate is more humid than the Trieste's one. Only in springtime Duino is less rainy than Trieste according lo the analysis of the monthly mean values of precipitation. From the ecophysiological point of view, a study of the seasonal changes of the root hydraulic conductance in some forest trees (Nardini el al .. 1998 has pointed out the superiority of Quercus ilex compared to Quercus pubescens, as regards the competitive ability of the seedlings during the spring. For this reason, the smaller spring rainfall could explain the occurrence of Quercus ilex stands not only in the neighbourhood of Duino but also at the beginning of the large valleys characterized by S•N direction in the South Eastern Alps.

  13. Hydrological drought types in cold climates: quantitative analysis of causing factors and qualitative survey of impacts

    OpenAIRE

    A. F. Van Loon; S. W. Ploum; Parajka, J.; A. K. Fleig; Garnier, E.; Laaha, G.; H. A. J. van Lanen

    2015-01-01

    For drought management and prediction, knowledge of causing factors and socio-economic impacts of hydrological droughts is crucial. Propagation of meteorological conditions in the hydrological cycle results in different hydrological drought types that require separate analysis. In addition to the existing hydrological drought typology, we here define two new drought types related to snow and ice. A snowmelt drought is a deficiency in the s...

  14. The Orographic Climate Factors Contributing to the Mass Balance of Small Glaciers in North-Iceland

    OpenAIRE

    Halkola, Kaisa

    2005-01-01

    This report is a result of a master thesis project. The project was launched to get more information of the factors affecting the mass balance of small glaciers in Northern Iceland. Observations on the glaciers were analysed in comparison with previous estimations of mass balance (Eythorsson and Sigtryggsson, 1971), a degree-day mass-balance model (MBT) and an atmospheric model MM5 (National Centre for Atmospheric Research (NCAR) / Pennsylvania State University).

  15. Climatic controls on leaf litter decomposition across European forests and grasslands revealed by reciprocal litter transplantation experiments

    Science.gov (United States)

    Portillo-Estrada, Miguel; Pihlatie, Mari; Korhonen, Janne F. J.; Levula, Janne; Frumau, Arnoud K. F.; Ibrom, Andreas; Lembrechts, Jonas J.; Morillas, Lourdes; Horváth, László; Jones, Stephanie K.; Niinemets, Ülo

    2016-03-01

    Carbon (C) and nitrogen (N) cycling under future climate change is associated with large uncertainties in litter decomposition and the turnover of soil C and N. In addition, future conditions (especially altered precipitation regimes and warming) are expected to result in changes in vegetation composition, and accordingly in litter species and chemical composition, but it is unclear how such changes could potentially alter litter decomposition. Litter transplantation experiments were carried out across six European sites (four forests and two grasslands) spanning a large geographical and climatic gradient (5.6-11.4 °C in annual temperature 511-878 mm in precipitation) to gain insight into the climatic controls on litter decomposition as well as the effect of litter origin and species. The decomposition k rates were overall higher in warmer and wetter sites than in colder and drier sites, and positively correlated with the litter total specific leaf area. Also, litter N content increased as less litter mass remained and decay went further. Surprisingly, this study demonstrates that climatic controls on litter decomposition are quantitatively more important than species or site of origin. Cumulative climatic variables, precipitation, soil water content and air temperature (ignoring days with air temperatures below zero degrees Celsius), were appropriate to predict the litter remaining mass during decomposition (Mr). Mr and cumulative air temperature were found to be the best predictors for litter carbon and nitrogen remaining during the decomposition. Using mean annual air temperature, precipitation, soil water content and litter total specific leaf area as parameters we were able to predict the annual decomposition rate (k) accurately.

  16. Climatic and lacustrine morphometric controls of diatom paleoproductivity in a tropical Andean lake

    Science.gov (United States)

    Bao, R.; Hernández, A.; Sáez, A.; Giralt, S.; Prego, R.; Pueyo, J. J.; Moreno, A.; Valero-Garcés, B. L.

    2015-12-01

    The coupling of lake dynamics with catchment biogeochemistry is considered the key element controlling primary production in mountain lakes at time scales of a few decades to millennia, yet little is known on the impacts of the morphometry of lakes throughout their ontogeny. As Lake Chungará (Central Andean Altiplano, northern Chile) experienced long-term lake-level fluctuations that strongly modified its area:volume ratio, it is an ideal system for exploring the relative roles that long-term climatic shifts and lake morphometry play on biosiliceous lacustrine productivity. In this paper, we review previous data on the percent contents of total organic carbon, total inorganic carbon, total nitrogen, total biogenic silica, isotopic composition of organic matter, carbonates, and diatom frustules, as well as data on the abundance of the chlorophycean Botryococcus braunii in this lake for the period 12,400-1300 cal yr BP. We also include new data on organic carbon and biogenic silica mass accumulation rates and the diatom assemblage composition of an offshore core dated using 14C and U/Th. Biosiliceous productivity in Lake Chungará was influenced by shifts in allochthonous nutrient inputs related to variability in precipitation. Humid phases dated at approx. 12,400 to 10,000 and 9600 to 7400 cal yr BP coincide with periods of elevated productivity, whereas decreases in productivity were recorded during arid phases dated at approx. 10,000 to 9600 and 7400 to 3550 cal yr BP (Andean mid-Holocene Aridity Period). However, morphometry-related in-lake controls led to a lack of a linear response of productivity to precipitation variability. During the late Glacial to early Holocene, lowstands facilitated complete water column mixing, prompting episodic massive blooms of a large centric diatom, Cyclostephanos cf. andinus. Thus, moderate productivity could be maintained, regardless of aridity, by this phenomenon of morphometric eutrophy during the early history of the lake

  17. CubeSat Form Factor Thermal Control Louvers Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Thermal control of small spacecraft, including CubeSats, is a challenge for the next era of NASA spaceflight. Science objectives and components will still require...

  18. Climate change impacts: The challenge of quantifying multi-factor causation, multi-component responses, and leveraging from extremes

    Science.gov (United States)

    Field, C. B.

    2012-12-01

    Modeling climate change impacts is challenging for a variety of reasons. Some of these are related to causation. A weather or climate event is rarely the sole cause of an impact, and, for many impacts, social, economic, cultural, or ecological factors may play a larger role than climate. Other challenges are related to outcomes. Consequences of an event are often most severe when several kinds of responses interact, typically in unexpected ways. Many kinds of consequences are difficult to quantify, especially when they include a mix of market, cultural, personal, and ecological values. In addition, scale can be tremendously important. Modest impacts over large areas present very different challenges than severe but very local impacts. Finally, impacts may respond non-linearly to forcing, with behavior that changes qualitatively at one or more thresholds and with unexpected outcomes in extremes. Modeling these potentially complex interactions between drivers and impacts presents one set of challenges. Evaluating the models presents another. At least five kinds of approaches can contribute to the evaluation of impact models designed to provide insights in multi-driver, multi-responder, multi-scale, and extreme-driven contexts, even though none of these approaches is a complete or "silver-bullet" solution. The starting point for much of the evaluation in this space is case studies. Case studies can help illustrate links between processes and scales. They can highlight factors that amplify or suppress sensitivity to climate drivers, and they can suggest the consequences of intervening at different points. While case studies rarely provide concrete evidence about mechanisms, they can help move a mechanistic case from circumstantial to sound. Novel approaches to data collection, including crowd sourcing, can potentially provide tools and the number of relevant examples to develop case studies as statistically robust data sources. A critical condition for progress in this

  19. Climate variability controls on unsaturated water and chemical movement, High Plains aquifer, USA

    Science.gov (United States)

    Gurdak, J.J.; Hanson, R.T.; McMahon, P.B.; Bruce, B.W.; McCray, J.E.; Thyne, G.D.; Reedy, R.C.

    2007-01-01

    Responses in the vadose zone and groundwater to interannual, interdecadal, and multidecadal climate variability have important implications for groundwater resource sustainability, yet they are poorly documented and not well understood in most aquifers of the USA. This investigation systematically examines the role of interannual to multidecadal climate variability on groundwater levels, deep infiltration (3-23 m) events, and downward displacement (>1 m) of chloride and nitrate reservoirs in thick (15-50 m) vadose zones across the regionally extensive High Plains aquifer. Such vadose zone responses are unexpected across much of the aquifer given a priori that unsaturated total-potential profiles indicate upward water movement from the water table toward the root zone, mean annual potential evapotranspiration exceeds mean annual precipitation, and millennia-scale evapoconcentration results in substantial vadose zone chloride and nitrate reservoirs. Using singular spectrum analysis (SSA) to reconstruct precipitation and groundwater level time-series components, variability was identified in all time series as partially coincident with known climate cycles, such as the Pacific Decadal Oscillation (PDO) (10-25 yr) and the El Nin??o/Southern Oscillation (ENSO) (2-6 yr). Using these lag-correlated hydrologic time series, a new method is demonstrated to estimate climate-varying unsaturated water flux. The results suggest the importance of interannual to interdecadal climate variability on water-flux estimation in thick vadose zones and provide better understanding of the climate-induced transients responsible for the observed deep infiltration and chemical-mobilization events. Based on these results, we discuss implications for climate-related sustainability of the High Plains aquifer. ?? Soil Science Society of America.

  20. Investigation and control of factors influencing resistance upset butt welding.

    NARCIS (Netherlands)

    Kerstens, N.F.H.

    2010-01-01

    The purpose of this work is to investigate the factors influencing the resistance upset butt welding process to obtain an understanding of the metal behaviour and welding process characteristics, so that new automotive steels can be welded with reduced development time and fewer failures in producti

  1. Climatic factors and reindeer grazing -- the effects on soil carbon dynamics in subarctic boreal pine forest.

    Science.gov (United States)

    Köster, Kajar; Köster, Egle; Berninger, Frank; Pumpanen, Jukka

    2016-04-01

    Reindeer (Rangifer tarandus L.) are the most important large mammalian herbivores in the northern ecosystems, affecting plant diversity, soil nutrient cycling and soil organic matter decomposition. Changes caused by reindeer in vegetation have indirect effects on physical features of the soil e.g. soil microclimate, root biomass and also on soil carbon dynamics. In a field experiment in Finnish Lapland, Värriö Strict Nature Reserve (67° 46' N, 29° 35' E) we investigated how the reindeer grazing in subarctic boreal forest combined with climate (air temperature and precipitation) affects soil temperature, soil water content, and ultimately the CO2 efflux from forest soils. The study was carried out in the growing seasons of the years 2013 and 2014, where 2013 was an extremely dry year (specially the summer), and the year 2014 was a "normal" year in means of precipitations. Our study areas are located in the northern boreal subarctic coniferous forest at the zone of the last intact forest landscapes in Fennoscandia, where large areas of relatively undisturbed subarctic Scots pine (Pinus sylvestris L.) forests can still be found. We established the experiment as a split plot experiment with 2 blocks and 5 sub-plots per treatment that were divided into grazed and non-grazed parts, separated with a fence. The sample plots are located along the borderline between Finland and Russia, where the ungrazed area was excluded from reindeer already in 1918, to prevent the Finnish reindeer from going to the Russian side and there are not many reindeer on Russian side of the area. Our study showed that in subarctic mature pine forests, soil temperatures were higher, and soil water content was fluctuating more on grazed areas compared to non-grazed areas in both years. In both years, the soil water content on the grazed area was highest in June. The situation changed somewhere in the second half of July when the moisture content in the non-grazed area was higher. We found

  2. Utilizing Remote Sensing to Explore Hydrological and Climatic Factors of Visceral Leishmaniasis in South Sudan

    Science.gov (United States)

    Kruczkiewicz, A.; Sweeney, A.; Reid, C.; Seaman, J.; Abubakar, A.; Ritmeijer, K.; Jensen, K.; Schroeder, R.; McDonald, K. C.; Lessel, J.; Thomson, M. C.; Elnaiem, D.; Ceccato, P.

    2014-12-01

    Recent epidemics of visceral leishmaniasis (VL) in Sudan and South Sudan (locally known as Kala Azar) have caused an estimated 100,000 deaths and have renewed the impetus for defining the ecological boundaries of this vector borne disease. In the past 30 years outbreaks have occurred cyclically within this country, but recent shifts in endemicity have necessitated a more robust understanding of the drivers of the disease. Previous work (e.g. Gebre-Michael et al., 2004; Ashford & Thomson, 1991; Hoogstraal & Heyneman, 1969) has suggested that the primary biological vector in this region, the female sand fly Phlebotomus orientalis, exhibits sensitivities to environmental and climatic variables. Results of this study showed a relationship between precipitation and inundation during months of the transmission season (April-July) and the number of confirmed cases in the following September-January period. Particular months of the transmission season with below-average precipitation were better indicators of lagged reports of VL than others. During VL epidemics (2009, 2010, 2011) the month of June exhibited below average precipitation. The two largest epidemics (2010, 2011) were associated with years of below average precipitation in the month of April. Inundation during April-July (AMJJ) also exhibited a strong inverse relationship with reported VL cases in the following September- January (SONDJ). This relationship was best explored when comparing the VL case data of a specific medical center to the inundation anomalies. Results are typified by the Lankien Medical Center analysis where below average inundation during April displays an inverse relationship with VL cases in the following SONDJ. Drought may lead to below average inundation, which could allow for soils to maintain their fissures, thus maintaining the sand fly breeding habitat, resulting in a sustained breeding season for the sandflies (Quate, 1964). Above-average precipitation and inundation might have the

  3. Poor stroke-related risk factor control even after stroke: an opportunity for rehabilitation professionals.

    Science.gov (United States)

    Ellis, Charles; Breland, Hazel L

    2014-01-01

    The burden of chronic disease worldwide is substantial. Unfortunately, risk factor control for most chronic diseases remains poor even after diagnoses. This is a major concern because poor risk factor control often leads to secondary consequences of the disease and the development of co-existing diseases. Stroke is a chronic condition that frequently requires the services of rehabilitation professionals who can also play an important role in risk factor management to reduce recurrent stroke. Approaches to the management of stroke risk factors in stroke survivors vary greatly and consequently outcomes vary in a similar fashion. The current literature suggests that uniform offering of structured risk factor control programs over time to individuals with chronic disease can improve knowledge of stroke risk factors, knowledge of action to control risk factors and in turn facilitate self-management practices that reduce the negative consequences of chronic diseases. Rehabilitation professionals can play a vital role in the management and secondary prevention of chronic diseases during the rehabilitation process via patient education and training. Implications for Rehabilitation Evidence suggests that risk factor control remains poor in many individuals with chronic conditions such as stroke. Rehabilitation professionals can play a key role in programs designed to improve risk factor control in chronic conditions. Future risk factor control programs can be structured and implemented over time to include rehabilitation professionals.

  4. Regional and historical factors supplement current climate in shaping global forest canopy height

    DEFF Research Database (Denmark)

    Zhang, Jian; Nielsen, Scott; Mao, Lingfeng;

    2016-01-01

    Summary Canopy height is a key factor that affects carbon storage, vegetation productivity and biodiversity in forests, as well as an indicator of key processes such as biomass allocation. However, global variation in forest canopy height and its determinants are poorly known. We used global data...... for 32 304 forested 55-km grid cells using 1-km global canopy height data (maximum height of 1-km cells within a 55-km grid). Variation in Hmax was related to latitude and biomes, along with environmental and historical variables. Both spatial and non-spatial linear models were used to assess...

  5. Modeling and Control of DC/DC Boost Converter using K-Factor Control for MPPT of Solar PV System

    DEFF Research Database (Denmark)

    Vangari, Adithya; Haribabu, Divyanagalakshmi; Sakamuri, Jayachandra N.

    2015-01-01

    is presented. Design of the passive elements of the boost converter as per the system specifications is also illustrated. The performance of the proposed K factor control method is verified with the simulations for MPPT on solar PV system at different atmospheric conditions. A new circuit based model for solar......This paper is focused on the design of a controller for the DC/DC boost converter using K factor control, which is based on modified PI control method, for maximum power point tracking (MPPT) of solar PV system. A mathematical model for boost converter based on small signal averaging approach...

  6. Control of safety factor profile in infinite dimension tokamak plasmas

    International Nuclear Information System (INIS)

    The increasing energy needs of the world population require the development, the control and the supply of new forms of energy. In this context, nuclear fusion is a track of extremely promising research. World project ITER is intended to prove the scientific and technical feasibility of nuclear fusion. One of the many key-goal is the control of the current profile spatial distribution in plasmas of tokamak, which is one of the main parameter for the stability and the performance of the experiments. The spatio-temporal evolution of this current is described by a set of nonlinear partial differential equations. In this document stabilization is proposed considering robust control of current profile spatial distribution in infinite dimension. Two approaches are proposed: the first one is based on sliding mode approach and the second one (of type proportional and proportional integral) is based on the Lyapunov functions in infinite dimension. The design of the control law is based on the 1D equation resistive diffusion of the magnetic flux. The control laws are calculated in infinite dimension without space discretization. (author)

  7. Emission Certificate Trade and Costs under Regional Burden-Sharing Regimes for a 2˚C Climate Change Control Target

    NARCIS (Netherlands)

    T. Kober; B.C.C. van der Zwaan; H. Rösler

    2014-01-01

    In this article we explore regional burden-sharing regimes for the allocation of greenhouse gas emission reduction obligations needed to reach a 2°C long-term global climate change control target by performing an integrated energy-economy-climate assessment with the bottom-up TIAM-ECN model. Our mai

  8. Eustatic and climatic control on the Upper Muschelkalk Sea (late Anisian/Ladinian) in the Central European Basin

    Science.gov (United States)

    Franz, M.; Kaiser, S. I.; Fischer, J.; Heunisch, C.; Kustatscher, E.; Luppold, F. W.; Berner, U.; Röhling, H.-G.

    2015-12-01

    The Upper Muschelkalk in the Central European Basin (CEB) is a key example of eustatic and climatic controls on inland seas. The late Anisian rapid transgression from Tethyan waters culminated in a large semi-enclosed inland sea stretching across the CEB. Subsequently, the slow but successive retreat in the early Ladinian resulted in a small remnant sea. The pronounced stratal pattern architectures are translated into a framework of 3rd- and 4th-order T-R sequences. The latest Illyrian 3rd-order maximum flooding surface corresponds to maximum abundances of carbonates and marine phytoplankton. An euryhaline marine ecology is indicated by prasinophycean algae dominating over acritarchs and δ18OP values of 18.9-22.4‰ VSMOW corresponding to Tethyan references. During the 3rd-order regressive phase successive freshening up to hyposaline conditions is indicated by up to 3‰ depleted δ18OP values, shifts to more radiogenic 87Sr/86Sr ratios and maximum abundances of terrestrial palynomorphs. Likewise, 4th-order T-R sequences are constrained by commutated stratal pattern architectures, palynofacies and geochemistry. The favourable correlation of middle Triassic 3rd-order sequences of Tethyan and peri-Tethyan basins demonstrate the principle control of circum-Tethyan eustatic cycles. 4th-order sequences are evident and, although not yet correlatable in detail, indicate 106-year scale eustatic cycles which may be attributed to glacioeustatic sea-level changes. The subordinated control of arid to semiarid low latitude and semihumid to humid temperate mid latitude climates affected the Upper Muschelkalk Sea in particular during 4th-order sea-level lowstands. Substantial fresh water input from Scandinavian sources caused temporal stratification leading to stagnant bottom waters and/or sediments as indicated by palynofacies and U/Th and Ni/Co redox indices. The herein reconstructed middle Triassic zonal climates are in agreement to previously published Late Triassic zonal

  9. Addressing the human factors issues associated with control room modifications

    Energy Technology Data Exchange (ETDEWEB)

    O`Hara, J.; Stubler, W. [Brookhaven National Lab., Upton, NY (United States). Dept. of Advanced Technology; Kramer, J. [Nuclear Regulatory Commission, Washington, DC (United States). Office of Nuclear Regulatory Research

    1998-03-01

    Advanced human-system interface (HSI) technology is being integrated into existing nuclear plants as part of plant modifications and upgrades. The result of this trend is that hybrid HSIs are created, i.e., HSIs containing a mixture of conventional (analog) and advanced (digital) technology. The purpose of the present research is to define the potential effects of hybrid HSIs on personnel performance and plant safety and to develop human factors guidance for safety reviews of them where necessary. In support of this objective, human factors issues associated with hybrid HSIs were identified. The issues were evaluated for their potential significance to plant safety, i.e., their human performance concerns have the potential to compromise plant safety. The issues were then prioritized and a subset was selected for design review guidance development.

  10. Harmonic Resonance Analysis for PEP II Power Factor Control Upgrades

    Science.gov (United States)

    Corvin, C.

    1997-05-01

    Recent upgrades to the high voltage utility distribution network at the Stanford Linear Accelerator Center have been accompanied by the installation of a large number of power supplies associated with the PEP-II B Factory project. These power supplies include a diverse assortment of single and three phase units, in two, six and twelve pulse configurations, with chopped, pulsed and continuous loading. Viewed as harmonic power sources in a range from a hundred to several kilohertz, they have the potential to be in resonance with the utility system network, a condition to be avoided. This paper analyzes and evaluates these resonance conditions with a view toward adding electric power factor correction upgrades to achieve substantial cost savings associated with power factor penalty avoidance. Similar studies and upgrades at SLAC in the past have reduced electric power costs over time by several hundred thousand dollars, thus providing the incentive to evaluate the recent upgrades to the PEP-II utility network.

  11. Polyketide chain length control by chain length factor.

    Science.gov (United States)

    Tang, Yi; Tsai, Shiou-Chuan; Khosla, Chaitan

    2003-10-22

    Bacterial aromatic polyketides are pharmacologically important natural products. A critical parameter that dictates product structure is the carbon chain length of the polyketide backbone. Systematic manipulation of polyketide chain length represents a major unmet challenge in natural product biosynthesis. Polyketide chain elongation is catalyzed by a heterodimeric ketosynthase. In contrast to homodimeric ketosynthases found in fatty acid synthases, the active site cysteine is absent from the one subunit of this heterodimer. The precise role of this catalytically silent subunit has been debated over the past decade. We demonstrate here that this subunit is the primary determinant of polyketide chain length, thereby validating its designation as chain length factor. Using structure-based mutagenesis, we identified key residues in the chain length factor that could be manipulated to convert an octaketide synthase into a decaketide synthase and vice versa. These results should lead to novel strategies for the engineered biosynthesis of hitherto unidentified polyketide scaffolds.

  12. Investigation and control of factors influencing resistance upset butt welding.

    OpenAIRE

    Kerstens, N.F.H.

    2010-01-01

    The purpose of this work is to investigate the factors influencing the resistance upset butt welding process to obtain an understanding of the metal behaviour and welding process characteristics, so that new automotive steels can be welded with reduced development time and fewer failures in production. In principle the welding process is rather simple, the materials to be joined are clamped between two electrodes and pressed together. Because there is an interface present with a higher resist...

  13. Quantification of Multiple Climate Change and Human Activity Impact Factors on Flood Regimes in the Pearl River Delta of China

    Directory of Open Access Journals (Sweden)

    Yihan Tang

    2016-01-01

    Full Text Available Coastal flood regimes have been irreversibly altered by both climate change and human activities. This paper aims to quantify the impacts of multiple factors on delta flood. The Pearl River Delta (PRD, with dense river network and population, is one of the most developed coastal areas in China. The recorded extreme water level (m.s.l. in flood season has been heavily interfered with by varied income flood flow, sea-level rise, and dredged riverbeds. A methodology, composed of a numerical model and the index R, has been developed to quantify the impacts of these driving factors in the the PRD. Results show that the flood level varied 4.29%–53.49% from the change of fluvial discharge, 3.35%–38.73% from riverbed dredging, and 0.12%–16.81% from sea-level rise. The variation of flood flow apparently takes the most effect and sea-level rise the least. In particular, dense river network intensifies the impact of income flood change and sea-level rise. Findings from this study help understand the causes of the the PRD flood regimes and provide theoretical support for flood protection in the delta region.

  14. Factors Contributing to Self Control for Incarcerated Youth

    Science.gov (United States)

    Winquist, Trancita

    2010-01-01

    This study was conducted to examine characteristics contributing to high self control for incarcerated youth. Subjects include fifty youth (8 females and 42 males) ages 14 through 18 incarcerated for at least 60 days. Data on subjects' responses from a validated measure (Grasmick et. al. Scale, 1993) and data from historical records, STAR reading…

  15. Factors Relating to Staff Attributions of Control over Challenging Behaviour

    Science.gov (United States)

    Dilworth, Jennifer A.; Phillips, Neil; Rose, John

    2011-01-01

    Background: Previous research has suggested that severity of intellectual disability (ID) and topography of behaviour may influence staff causal attributions regarding challenging behaviour. Subsequently, these causal attributions may influence helping behaviours. This study investigated the relationship between attributions of control over…

  16. Resource Form Factor and Installation of GFA Controllers

    Energy Technology Data Exchange (ETDEWEB)

    DeSteese, John G.; Hammerstrom, Donald J.

    2009-11-15

    The focus of this task is to optimize the form and placement of a controller comprising the Grid Friendly™ appliance (GFA) controller, power supply and power relay (and/or a solid-state power electronic switch) that would command a domestic water heater to shed its load in response to stress on the electric power grid. The GFA controller would disconnect the water heater from its supply circuit whenever it senses a low voltage signal or other indicators of system stress communicated via the electric power distribution system. Power would be reconnected to the appliance when the GFA controller senses the absence of these signals. This project has also considered more frequent cycling of this controller’s relay switch to perform demand-side frequency regulation. The principal criteria considered in this optimization are reliability, cost and life expectancy of the GFA components. The alternative embodiments of the GFA equipment under consideration are: Option 1- installation inside the insulation space of the water heater between the tank and jacket Option 2 containment in a separate nearby electrical enclosure Option 3 - as a modification or adjunct to the distribution panel housing and/or the breaker that protects the water heater supply circuit.

  17. The Controllable Lifestyle Factor and Students' Attitudes about Specialty Selection.

    Science.gov (United States)

    Schwartz, Richard W.; And Others

    1990-01-01

    Students were asked to state their selected specialty and to rank the importance that each of 25 influences listed on a questionnaire had in making their specialty choice. Selected specialties were classified into three groups: noncontrollable lifestyle, controllable lifestyle, and surgery. (MLW)

  18. Factors Controlling Nanoparticle Pharmacokinetics: An Integrated Analysis and Perspective

    DEFF Research Database (Denmark)

    Moghimi, Seyed Moien; Hunter, A.C.; Andresen, T.L.

    2012-01-01

    Intravenously injected nanoparticulate drug carriers provide a wide range of unique opportunities for site-specific targeting of therapeutic agents to many areas within the vasculature and beyond. Pharmacokinetics and biodistribution of these carriers are controlled by a complex array of interrel...

  19. Different climatic controls of soil δ13Corg in three mid-latitude regions of the Northern Hemisphere since the Last Glacial period

    Institute of Scientific and Technical Information of China (English)

    RAO ZhiGuo; ZHU ZhaoYu; ZHANG JiaWu

    2007-01-01

    Paleoecological records of soil δ13Corg from three regions in the middle latitudes of the Northern Hemisphere, including the Chinese Loess Plateau (CLP), the Great Plains and adjacent areas of North America and northwestern Europe, showed different variations since the Last Glacial period. An attempt was made to evaluate the causes for the difference in δ13Corg on the basis of the modern climatic data collected in these regions and of the modern C3 and C4 plant distributions. The analysis indicates that temperature, especially the growing season temperature, has a dominant control on the growth of C4 plants. When the mean annual or growing season temperatures are below the "threshold value", the growth of C4 plants is limited. When the temperature is above the "threshold value", C4 plants can grow under a wide range of precipitation. However, when the precipitation is high enough to favor the growth of trees, the proportions of C4 plants in local biomass will decline. The implicit control factor recovered by sedimentary records is consistent with the control factor on modern C3/C4 distribution. Pure C3 plants have been dominating the local biomass since the Last Glacial period in European loess region, mainly owing to the low local temperature. The increases in C4 plants from the late Pleistocene to the Holocene in the Chinese Loess Plateau, the Great Plains and adjacent areas, mainly reflect the influence of increasing temperature.

  20. Influence of climatic and hydrological factors on structure and composition of peat from northern wetland territories with low anthropogenic impact.

    Science.gov (United States)

    Parfenova, L N; Selyanina, S B; Trufanova, M V; Bogolitsyn, K G; Orlov, A S; Volkova, N N; Ponomareva, T I; Sokolova, T V

    2016-05-01

    Northern wetlands ecosystems play an important role in the hydrological balance of neighboring areas, where they act as chemical barriers against anthropogenic and technogenic contaminations. Studied region is well known for quantity of peat deposits and the volume of peat resources. Peat can be considered as a highly informative marker for assessing change in environmental conditions. The study presents the results of the first investigation of peat samples, collected from representative ecosystems of northern wetland territories with low anthropogenic impact. Component and element composition of various peat types were studied in a relation to hydrologic, climate and sampling conditions. It was found out that organic and ash contents are more dependent on the type of the bog, than geographic location. Climatic factors are more important for the formation of bitumen. The degradation degree in peat increases proportionally to content of humates. High content of biogenic and lithogenic elements was observed in transition- and low-moor peat. The content of trace elements in peat samples do not depend on the type of the peat. The structural properties of peat were studied by the light microscopy, AFM and dynamic light scattering. It was determined that the conformation of studied peat samples is characterized by elements of asymmetry. The observed particles in the solutions exist in dynamic equilibrium with separated globular macromolecules. The size of these nanoparticles is comparable with the size of the particles of other biopolymers of similar nature. Swelling of peat in liquid water was studied. The relationship between structural specificities, origin of peat and its maximum degree of swelling was found. The degree of swelling can be used as structural-sensitive parameter in further research. PMID:26874767

  1. Prevalence of tick borne encephalitis virus in tick nymphs in relation to climatic factors on the southern coast of Norway

    Directory of Open Access Journals (Sweden)

    Andreassen Ashild

    2012-08-01

    Full Text Available Abstract Background Tick-borne encephalitis (TBE is among the most important vector borne diseases of humans in Europe and is currently identified as a major health problem in many countries. TBE endemic zones have expanded over the past two decades, as well as the number of reported cases within endemic areas. Multiple factors are ascribed for the increased incidence of TBE, including climatic change. The number of TBE cases has also increased in Norway over the past decade, and the human cases cluster along the southern coast of Norway. In Norway the distribution and prevalence of TBE virus (TBEV in tick populations is largely unknown. The objectives of this study were to estimate the TBEV prevalence in Ixodes ricinus from seven locations and to assess the relationship between the TBEV prevalence and site-specific climatic variables. Methods A total of 5630 questing nymphs were collected and analyzed in pools of ten. All pools were screened with an in-house real-time RT-PCR, and the positive pools were pyrosequenced. Two methods, minimum infection rate (MIR and a frequentist method (EPP for pooled prevalence estimations were calculated and compared. Climatic data were descriptively compared to the corresponding EPP of each location in order to explain variations in TBEV prevalence. Results The seven foci of TBEV had an estimated overall prevalence (EPP in pools of nymphs combined, of 0.53% with 95% CI (0.35–0.75, with point prevalence ranging between 0.11%–1.22%. The sites with the highest point prevalences were within the municipalities which had the highest numbers of registered TBE cases. The results indicate that the location with highest point prevalence had the highest relative mean humidity and lowest mean saturation deficit and vice versa for the lowest EPP. Conclusion Our study confirms the existence of TBEV endemic foci in Norway. These results are of importance to increase the awareness of TBEV infections in Norway and could be

  2. Strong climate and tectonic control on plagioclase weathering in granitic terrain

    Science.gov (United States)

    Rasmussen, C.; Brantley, S.; Richter, D.D.B.; Blum, A.; Dixon, J.; White, A.F.

    2011-01-01

    Investigations to understand linkages among climate, erosion and weathering are central to quantifying landscape evolution. We approach these linkages through synthesis of regolith data for granitic terrain compiled with respect to climate, geochemistry, and denudation rates for low sloping upland profiles. Focusing on Na as a proxy for plagioclase weathering, we quantified regolith Na depletion, Na mass loss, and the relative partitioning of denudation to physical and chemical contributions. The depth and magnitude of regolith Na depletion increased continuously with increasing water availability, except for locations with mean annual temperature Elsevier B.V.

  3. Climate, herbivory, and fire controls on tropical African forest for the last 60ka

    Science.gov (United States)

    Ivory, Sarah J.; Russell, James

    2016-09-01

    The Last Glacial Maximum (LGM) in Africa was drier than today and was followed by rapid step-wise climate changes during the last deglacial period. In much of Africa, these changes led to a drastic reduction of lowland forest area during the LGM, followed by recolonization of the lowlands by forest and woodland in concert with regional warming and wetting. However, the history of southeastern African vegetation contrasts with that observed further north. In particular, forest expansion appears to have occurred in southeastern Africa during episodes of high-latitude northern hemisphere cooling. Although vegetation history in Africa is generally assumed to relate purely to climate, previous studies have not addressed potential feedbacks between climate, vegetation, and disturbance regimes (fire, herbivory) that may create tipping points in ecosystems. This climate-vegetation history has profound implications for our understanding of the modern architecture of lowland and highland forests, both thought to be at risk from future climate change. Here we present analyses of fossil pollen, charcoal, and Sporormiella (dung fungus) on a continuous 60 kyr record from central Lake Tanganyika, Southeast Africa, that illustrates the interplay of climate and disturbance regimes in shaping vegetation composition and structure. We observe that extensive forests dominated the region during the last glacial period despite evidence of decreased rainfall. At the end of the LGM, forest opening at ∼17.5 ka followed warming temperatures but preceded rising precipitation, suggesting that temperature-induced water stress and disturbance from fire and herbivory affected initial landscape transformation. Our Sporormiella record indicates that mega-herbivore populations increased at the early Holocene. This higher animal density increased plant species richness and encouraged landscape heterogeneity until the mid-Holocene. At this time, regional drying followed by the onset of the Iron Age

  4. Smart Control of Air Climatization System in Function on the Values of Mean Local Radiant Temperature

    Directory of Open Access Journals (Sweden)

    Giuseppe Cannistraro

    2015-08-01

    Full Text Available The hygrothermal comfort indoor conditions are defined as: those environmental conditions in which an individual exposed, expresses a state of satisfaction. These conditions cannot always be achieved anywhere in an optimal way and economically; in some cases they can be obtained only in work environments specific areas. This could be explained because of air conditioning systems designing is generally performed both on the basis of the fundamental parameters’ average values, such as temperature, velocity and relative humidity (Ta, va e φa and derived parameters such as operating temperature and mean radiant one (Top eTmr. However, in some specific cases - large open-spaces or in case of radiating surfaces - the descriptors defining indoor comfort conditions, based on average values, do not provide the optimum values required during the air conditioning systems design phase. This is largely due to the variability of real environmental parameters values compared to the average ones taken as input in the calculation. The results obtained in previous scientific papers on the thermal comfort have been the driving element of this work. It offers a simple, original and clever way of thinking about the new domotic systems for air conditioning, based on the “local mean radiant temperature.” This is a very important parameter when one wants to analyze comfort in environments characterized by the presence of radiating surfaces, as will be seen hereinafter. In order to take into account the effects of radiative exchanges in the open-space workplace, where any occupant may find themselves in different temperature and humidity conditions, this paper proposes an action on the domotic climate control, with ducts and vents air distribution placed in different zones. Comparisons were performed between the parameters values representing the punctual thermal comfort, with the Predicted Mean Vote PMV, in an environment marked by radiating surfaces (i

  5. Air quality: how to assess air quality management policies on a short and on a long term? The integration of the climate factor

    International Nuclear Information System (INIS)

    This document presents the activities and works performed by the INERIS Institute in the development of tools for the assessment of air quality management policies including the climate factor. This comprises the development of simulations within the frame of the SALUT'AIR project, and also within the frame of the reviewing of the European policy on air quality (directives 2008/50/CE on ambient air quality and 2001/81/CE on national limits of emissions of some pollutants). The CHIMERE model of chemistry and transport is one of these tools. Simulations are performed to analyse the impact of scenarios of air quality management on a short term, in terms of pollutant emissions, pollutant concentration, and particle concentrations. The integration of a climate factor is justified by the existence of interactions between climate and air quality

  6. Study on the nutrient evolution and its controlling factors of Longgan Lake for the last 200 years

    Institute of Scientific and Technical Information of China (English)

    LIU; Jian; YANG; Xiangdong; WANG; Sumin

    2006-01-01

    Based on the total phosphorous (TP) concentration in sediment core, the TP concentration in lake water quantitatively reconstructed from fossil diatoms and diatom-TP transfer function in the Longgan Lake during the last 200 years, the temperature and precipitation data from meteorological observation for the last 50 years, the temperatures and precipitation sequences of climate simulation for the last 200 years, as well as the amount of the agricultural phosphate fertilizer in Longgan area for nearly 50 years, the characteristic and the law of the nutrient status evolution were analyzed, and the influence of the climatic factor, the anthropologic factor and the aquatic biology factor on the nutrient status evolution and its mechanism were discussed for the Longgan Lake during the last 200 years. The results showed that, in the nearly 200 years, the TP concentration in the sediment core of the Longgan Lake gradually increased, its range of variation was situated between 330-580 mg/kg, the mean value was 388 mg/kg, a nearly 30-year vibration adjustment period existed at 1950 around. The TP concentration in lake water changed in a different way. Before 1950, it had a slow increasing tendency in fluctuated background, to 1950 around it reached up to the mean value (52.18 μg/L), and vibrated and adjusted around the mean value, then it fast declined, its change range was situated between 37.75-62.33 μg/L. The analyses indicated that, in the centennial time scale, the climate change was the main controlling factor, while in the decadal time scale in the recent 50 years, human activities were the leading factors for the nutrient status evolution of the Longgan Lake. 60% of the variability of the TP concentration in the sediments and 57% of that in lake water were due to human activities. The differentiation between phosphorus concentration in the sediment and in the lake water reflected the response processes and the adjustment abilities of the lake aquatic ecosystems to

  7. Risk factors for Creutzfeldt-Jakob disease: a reanalysis of case-control studies.

    NARCIS (Netherlands)

    D.P.W.M. Wientjens (Dorothee); Z. Davanipour; K. Kondo; W.B. Matthews; R.G. Will (Robert); C.M. van Duijn (Cock); A. Hofman (Albert)

    1996-01-01

    textabstractTo review the evidence for risk factors of Creutzfeldt-Jakob disease (CJD), we pooled and reanalyzed the raw data of three case-control studies. The pooled data set comprised 178 patients and 333 control subjects. The strength of association between CJD and putative risk factors was asse

  8. Factores de riesgo para carcinoma basocelular: Estudio de casos-controles en Córdoba Risk factors for basal cell carcinoma: Case-control study in Cordoba

    Directory of Open Access Journals (Sweden)

    Alejandro Ruiz Lascano

    2005-12-01

    Full Text Available El carcinoma basocelular es una enfermedad compleja. Su etiología es todavía poco clara y a pesar de su frecuencia hay pocos datos sobre factores de riesgo. Nosotros evaluamos factores de riesgo potenciales para carcinoma basocelular en una población de Córdoba (Argentina. Este estudio de casos y controles incluyó a 88 casos nuevos de carcinoma basocelular, y 88 controles pareados por sexo y edad. Los siguientes factores de riesgo fueron significativos en el análisis multivariado: fototipos I, II y III, exposición solar recreativa alta después de los 20 años de edad, exposición solar alta en vacaciones en la playa y la presencia de queratosis actínicas.Basal cell carcinoma is undoubtedly a complex disease. Its etiology is still unclear and despite its frequency, there is a paucity of data on its risk factors. We assessed potential risk factors for basal cell carcinoma in a population from Córdoba (Argentina. This case-control study involved 88 newly diagnosed cases and 88 controls, matched by age and sex. The following risk factors were significant in the multivariate analysis: skin type I-II-III, high recreational sun exposure after 20 years of age, high sun exposure for beach holidays and actinic keratosis.

  9. Adaptive management in crop pest control in the face of climate variability: an agent-based modeling approach

    Directory of Open Access Journals (Sweden)

    François Rebaudo

    2015-06-01

    Full Text Available Climate changes are occurring rapidly at both regional and global scales. Farmers are faced with the challenge of developing new agricultural practices to help them to cope with unpredictable changes in environmental, social, and economic conditions. Under these conditions, adaptive management requires a farmer to learn by monitoring provisional strategies and changing conditions, and then incrementally adjust management practices in light of new information. Exploring adaptive management will increase our understanding of the underlying processes that link farmer societies with their environment across space and time, while accounting for the impacts of an unpredictable climate. Here, we assessed the impacts of temperature and crop price, as surrogates for climate and economic changes, on farmers' adaptive management in crop pest control using an agent-based modeling approach. Our model simulated an artificial society of farmers that relied on field data obtained in the Ecuadorian Andes. Farmers were represented as heterogeneous autonomous agents who interact with and influence each other, and who are capable of adapting to changing environmental conditions. The results of our simulation suggest that variable temperatures led to less effective pest control strategies than those used under stable temperatures. Moreover, farmers used information gained through their own past experience or through interactions with other farmers to initiate an adaptive management approach. At a broader scale, this study generates more than an increased understanding of adaptive management; it highlights how people depend on one another to manage common problems.

  10. Modeling the impact of climate and landscape on the efficacy of white tailed deer vaccination for cattle tick control in northeastern Mexico.

    Science.gov (United States)

    Estrada-Peña, Agustín; Carreón, Diana; Almazán, Consuelo; de la Fuente, José

    2014-01-01

    Cattle ticks are distributed worldwide and affect animal health and livestock production. White tailed deer (WTD) sustain and spread cattle tick populations. The aim of this study was to model the efficacy of anti-tick vaccination of WTD to control tick infestations in the absence of cattle vaccination in a territory where both host species coexist and sustain cattle tick populations. Agent-based models that included land cover/landscape properties (patch size, distances to patches) and climatic conditions were built in a GIS environment to simulate WTD vaccine effectiveness under conditions where unvaccinated cattle shared the landscape. Published and validated information on tick life cycle was used to build models describing tick mortality and developmental rates. Data from simulations were applied to a large territory in northeastern Mexico where cattle ticks are endemic and WTD and cattle share substantial portions of the habitat. WTD movements were simulated together with tick population dynamics considering the actual landscape and climatic features. The size of the vegetation patches and the distance between patches were critical for the successful control of tick infestations after WTD vaccination. The presence of well-connected, large vegetation patches proved essential for tick control, since the tick could persist in areas of highly fragmented habitat. The continued application of one yearly vaccination on days 1-70 for three years reduced tick abundance/animal/patch by a factor of 40 and 60 for R. annulatus and R. microplus, respectively when compared to non-vaccinated controls. The study showed that vaccination of WTD alone during three consecutive years could result in the reduction of cattle tick populations in northeastern Mexico. Furthermore, the results of the simulations suggested the possibility of using vaccines to prevent the spread and thus the re-introduction of cattle ticks into tick-free areas. PMID:25047078

  11. Modeling the impact of climate and landscape on the efficacy of white tailed deer vaccination for cattle tick control in northeastern Mexico.

    Directory of Open Access Journals (Sweden)

    Agustín Estrada-Peña

    Full Text Available Cattle ticks are distributed worldwide and affect animal health and livestock production. White tailed deer (WTD sustain and spread cattle tick populations. The aim of this study was to model the efficacy of anti-tick vaccination of WTD to control tick infestations in the absence of cattle vaccination in a territory where both host species coexist and sustain cattle tick populations. Agent-based models that included land cover/landscape properties (patch size, distances to patches and climatic conditions were built in a GIS environment to simulate WTD vaccine effectiveness under conditions where unvaccinated cattle shared the landscape. Published and validated information on tick life cycle was used to build models describing tick mortality and developmental rates. Data from simulations were applied to a large territory in northeastern Mexico where cattle ticks are endemic and WTD and cattle share substantial portions of the habitat. WTD movements were simulated together with tick population dynamics considering the actual landscape and climatic features. The size of the vegetation patches and the distance between patches were critical for the successful control of tick infestations after WTD vaccination. The presence of well-connected, large vegetation patches proved essential for tick control, since the tick could persist in areas of highly fragmented habitat. The continued application of one yearly vaccination on days 1-70 for three years reduced tick abundance/animal/patch by a factor of 40 and 60 for R. annulatus and R. microplus, respectively when compared to non-vaccinated controls. The study showed that vaccination of WTD alone during three consecutive years could result in the reduction of cattle tick populations in northeastern Mexico. Furthermore, the results of the simulations suggested the possibility of using vaccines to prevent the spread and thus the re-introduction of cattle ticks into tick-free areas.

  12. Understanding the Factors That Control Snow Albedo Over Central Greenland

    Science.gov (United States)

    Wright, P.; Bergin, M. H.; Dibb, J. E.; Domine, F.; Carmagnola, C.; Courville, Z.; Sokolik, I. N.; Lefer, B. L.

    2011-12-01

    Snow albedo plays a critical role in the energy balance of the Greenland Ice Sheet. In particular, the snow albedo influences the extent to which absorbing aerosols over Greenland (i.e. dust and black carbon) force climate. With this in mind the spectral snow albedo, physical snow properties, and snow chemistry were measured during May, June, and July 2011 at Summit, Greenland to investigate the variability in snow spectral albedo and its impact on aerosol direct radiative forcing. Optical and chemical properties of aerosol and aerosol optical depth were also measured as part of this study. Strellis et. al. will present a preliminary assessment of aerosol radiative forcing at Summit in summer 2011, in a separate presentation at this meeting. Spectral albedo was measured from 350-2500 nm with an ASD FieldSpec Pro spectroradiometer daily at four permanent sites and a moving fifth site where snow was sampled for characterization, as well as in more intensive diurnal and spatial surveys. Snow specific surface area (SSA), the ratio of snow crystal surface area to mass, was measured with a Dual Frequency Integrating Sphere (DUFISSS) at 1310 nm and 1550 nm, as well as with dyed and cast samples collected for stereology analysis. Snow stratigraphy, crystal size, and density were also measured on a daily basis, and snow samples will be analyzed for microstructural parameters determined from micro-CT imaging. Snow chemistry measurements include specific elements, major ions, and elemental and organic carbon. The time series of daily albedo measurements ranged from 0.88 to nearly 1.0 in visible wavelengths and from 0.42 to 0.65 in the near infrared. Changes as large as 0.1 were observed between consecutive daily measurements across the spectrum. Preliminary results show a strong correlation between variation in albedo and co-located measurements of snow specific surface area, specifically in the near infrared. By conducting our measurements near solar noon every day, and

  13. Organizational climate in air traffic control Innovative preparedness for implementation of new technology and organizational development in a rule governed organization.

    Science.gov (United States)

    Arvidsson, Marcus; Johansson, Curt R; Ek, Asa; Akselsson, Roland

    2006-03-01

    A positive and innovative organizational climate is of great importance in order to manage and adapt to change. Such a climate seldom evolves in organizations closely governed by rules and regulations. Because of ongoing organizational and technical changes within the Swedish Air Navigation Services Provider, a study concerning the organizational climate for changes and innovations was conducted to investigate the organization's capacity to cope with changes. Study locations were the two Swedish main air traffic control centers and parts of the civil aviation administration headquarters. In the study 390 subjects took part and the CCQ questionnaire was used to measure the organizational climate. The results show that the organizational climate is quite positive despite the rule-governed work. The results also show that administrative personnel assess the organizational climate as more positive than operative personnel. Comparisons between management positions did not result in any differences.

  14. Factors controlling the lipid composition of marine planktonic Thaumarchaeota

    OpenAIRE

    Elling, Felix J.

    2015-01-01

    Marine ammonia-oxidizing archaea of the phylum Thaumarchaeota synthesize glycerol dibiphytanyl glycerol tetraether (GDGT) membrane lipids that are used as for the reconstruction of sea surface temperatures by means of the TEX86 paleothermometer. Discrepancies between observed and predicted TEX86-temperatures throughout the global ocean indicate that the physiological and ecological controls on lipid composition in planktonic Thaumarchaeota remain poorly understood. In this thesis, the influen...

  15. Factors Controlling Methane in Arctic Lakes of Southwest Greenland

    Science.gov (United States)

    2016-01-01

    We surveyed 15 lakes during the growing season of 2014 in Arctic lakes of southwest Greenland to determine which factors influence methane concentrations in these systems. Methane averaged 2.5 μmol L-1 in lakes, but varied a great deal across the landscape with lakes on older landscapes farther from the ice sheet margin having some of the highest values of methane reported in lakes in the northern hemisphere (125 μmol L-1). The most important factors influencing methane in Greenland lakes included ionic composition (SO4, Na, Cl) and chlorophyll a in the water column. DOC concentrations were also related to methane, but the short length of the study likely underestimated the influence and timing of DOC on methane concentrations in the region. Atmospheric methane concentrations are increasing globally, with freshwater ecosystems in northern latitudes continuing to serve as potentially large sources in the future. Much less is known about how freshwater lakes in Greenland fit in the global methane budget compared to other, more well-studied areas of the Arctic, hence our work provides essential data for a more complete view of this rapidly changing region. PMID:27454863

  16. Local control on precipitation in a fully coupled climate-hydrology model

    DEFF Research Database (Denmark)

    Larsen, Morten A. D.; Christensen, Jens H.; Drews, Martin;

    2016-01-01

    simulations of precipitation often exhibit substantial biases that affect the reliability of future projections. Here we demonstrate how a regional climate model (RCM) coupled to a distributed hydrological catchment model that fully integrates water and energy fluxes between the subsurface, land surface...

  17. Climatic Controls on Summertime fog Patterns Along the U.S. West Coast

    Science.gov (United States)

    Williams, A. P.; Still, C.; Husak, G.; Michaelsen, J.

    2008-12-01

    Summertime fog and stratus overcast along the U.S. west coast significantly impact aviation, marine travel, agriculture, and biodiversity. However, an understanding of the climatic mechanisms that drive variability in fog formation and dissolution in this region, particularly on interannual time scales, is lacking, in part because fog data are collected at only a handful of coastal sites. Furthermore, fog is quite spatially variable and depends in part on local-scale features such as coastal topography and coastline orientation. As a result, accurate predictions of relative fogginess from one summer to the next have been elusive. This means that we do not know how coastal fogginess may change in response to global climate change. In this study, we treated all low stratus clouds as fog and used hourly records of summertime cloud height from 12 coastal stations along with daily satellite imagery to develop the first spatially continuous record of summertime fog occurrence along the California coast. Using statistical techniques to compare records of summer fog frequency to global gridded climate data, we created a statistical model that utilizes the organization of global sea surface temperatures and atmospheric pressures to estimate relative summer fogginess along California's coast. We then used GCM outputs based upon several climate change scenarios to predict how summer fog frequency may be expected to change during the 21st century. Finally, we used ecological niche modeling to predict how future changes in coastal fogginess might impact the range boundaries of several endemic plant species, including coast redwood.

  18. Sharing the story : Aboriginal and northern energy experiences : finding new ways for climate change control

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    One of society's top priorities is to reduce the effects of climate change. Since the effects of climate change are more pronounced in polar regions and energy costs are typically very high, Aboriginal and Northern communities have much to gain from improved energy efficiency and the use of renewable energy sources. This publication profiles some of the community-driven energy efficiency and renewable energy projects that were undertaken as part of the Aboriginal and Climate Change Program. The profiles are based on interviews conducted in 2002-2003 with individuals who were instrumental in seeing the projects completed. The projects demonstrated innovative approaches to adopt energy efficiency practices and renewable energy to create a sustainable way of life. The projects ranged from small hydro, wind power, solar energy and district heating with wood. Energy efficiency projects in housing and waste heat recovery were also highlighted. The benefits of the various projects included reduced transportation fuel and energy transmission costs, local employment and reduced greenhouse gas emissions that contribute to climate change. refs., tabs., figs.

  19. A description of the FAMOUS (version XDBUA climate model and control run

    Directory of Open Access Journals (Sweden)

    A. Osprey

    2008-12-01

    Full Text Available FAMOUS is an ocean-atmosphere general circulation model of low resolution, capable of simulating approximately 120 years of model climate per wallclock day using current high performance computing facilities. It uses most of the same code as HadCM3, a widely used climate model of higher resolution and computational cost, and has been tuned to reproduce the same climate reasonably well. FAMOUS is useful for climate simulations where the computational cost makes the application of HadCM3 unfeasible, either because of the length of simulation or the size of the ensemble desired. We document a number of scientific and technical improvements to the original version of FAMOUS. These improvements include changes to the parameterisations of ozone and sea-ice which alleviate a significant cold bias from high northern latitudes and the upper troposphere, and the elimination of volume-averaged drifts in ocean tracers. A simple model of the marine carbon cycle has also been included. A particular goal of FAMOUS is to conduct millennial-scale paleoclimate simulations of Quaternary ice ages; to this end, a number of useful changes to the model infrastructure have been made.

  20. Climate control on soil age and weathering thresholds in young, post-glacial soils of New Zealand

    Science.gov (United States)

    Dixon, J. L.; Chadwick, O.; Vitousek, P.

    2014-12-01

    Climate is often invoked as a major driver of soil and landscape evolution. But a coherent story has failed to emerge for how climate controls soil properties and weathering rates - partially due to competing influences of mineral residence times and supply rates in eroding landscapes. Here, we combine insights and methods across the related fields of geomorphology, soil science and geochemistry, to explore weathering thresholds in non-eroding, young soils along a strong precipitation gradient (400-4000 mm/yr) in the South Island of New Zealand. We studied ~30 soil profiles developed in thin (~1m) loess deposits that mantle LGM and post LGM moraines and outwash in the Waitaki catchment, extending from Lake Benmore to just below the Tasman glacier in the north. We find repeated thresholds (sharp, non-linear transitions) in soil chemistry, including exchangeable cations, pH and total elemental abundances. Abundance of pedogenic iron and aluminum increase with precipitation, stabilizing at ~2000 mm/yr. Plant-available phosphorous and exchangeable Ca and Mg are rapidly depleted as precipitation exceeds 1000 mm/yr. However total elemental abundances show up to 50% of major cations are retained at wetter sites, likely in less labile minerals. Preliminary numerical modeling of cation weathering kinetics provides some support for this interpretation. Together our data identify nonlinear changes in weathering intensity with rainfall, and show clear climate control on relatively young, post-glacial soil development. Additionally, we measured profiles and inventories of meteoric 10Be to quantify soil residence times across the climate gradient. This nuclide is cosmogenically produced in the atmosphere and binds strongly to reactive surfaces in soil following fallout. Exchangeable beryllium does not decrease with rainfall, despite decreasing pH along the climate gradient. Therefore we are confident that nuclide concentrations do not reflect leaching. Instead, these

  1. Study of fundamental physical principles in atmospheric modeling based on identification of atmosphere - climate control factors

    CERN Document Server

    Iudin, M

    2007-01-01

    Several critical review articles have been published on tropospheric halogen chemistry. One of the leading subjects of publications is the Arctic ozone depletion events (ODE) at polar sunrise. The articles deal with a wide spectrum of questions: from the detailed reaction cycles of chlorine, iodine and bromine species to processing of satellite data of vertical column BrO. For a long time, bromine explosion - natural phenomenon of exponential increase in gaseous Br radicals happening in springtime Arctic has remained main puzzle for explorers. In this paper, the possible bromine emission ground inventories in polar Arctic region are examined. Resulted model amounts of BrO and Bry equated satellite data on vertical column BrO. By looking at the bromine spread out in Arctic marine boundary layer (MBL) in the context of a network with rank linkage, the author rationalized model bromine flux empirical expression. Then, based on the obtained features of bromine explosion, author opens discussion on the parametrica...

  2. Climatic factors driving invasion of the tiger mosquito (Aedes albopictus into new areas of Trentino, northern Italy.

    Directory of Open Access Journals (Sweden)

    David Roiz

    Full Text Available BACKGROUND: The tiger mosquito (Aedes albopictus, vector of several emerging diseases, is expanding into more northerly latitudes as well as into higher altitudes in northern Italy. Changes in the pattern of distribution of the tiger mosquito may affect the potential spread of infectious diseases transmitted by this species in Europe. Therefore, predicting suitable areas of future establishment and spread is essential for planning early prevention and control strategies. METHODOLOGY/PRINCIPAL FINDINGS: To identify the areas currently most suitable for the occurrence of the tiger mosquito in the Province of Trento, we combined field entomological observations with analyses of satellite temperature data (MODIS Land Surface Temperature: LST and human population data. We determine threshold conditions for the survival of overwintering eggs and for adult survival using both January mean temperatures and annual mean temperatures. We show that the 0°C LST threshold for January mean temperatures and the 11°C threshold for annual mean temperatures provide the best predictors for identifying the areas that could potentially support populations of this mosquito. In fact, human population density and distance to human settlements appear to be less important variables affecting mosquito distribution in this area. Finally, we evaluated the future establishment and spread of this species in relation to predicted climate warming by considering the A2 scenario for 2050 statistically downscaled at regional level in which winter and annual temperatures increase by 1.5 and 1°C, respectively. CONCLUSIONS/SIGNIFICANCE: MODIS satellite LST data are useful for accurately predicting potential areas of tiger mosquito distribution and for revealing the range limits of this species in mountainous areas, predictions which could be extended to an European scale. We show that the observed trend of increasing temperatures due to climate change could facilitate further

  3. Holocene climate variations in the western Antarctic Peninsula: evidence for sea ice extent predominantly controlled by insolation and ENSO variability changes

    Directory of Open Access Journals (Sweden)

    J. Etourneau

    2013-01-01

    ENSO and climate variability in the WAP suggests that other climatic factors might have been more important in controlling WAP climate at this time.

  4. Disentangling the eruption source parameters that control the climate effects of volcanic eruptions

    Science.gov (United States)

    Marshall, Lauren; Schmidt, Anja; Mann, Graham; Carslaw, Kenneth; Dhomse, Sandip; Haywood, Jim; Jones, Andy

    2016-04-01

    Climatic cooling in the 1-2 years following a major volcanic eruption does not scale linearly with the mass of SO2 injected into the atmosphere. The injection height of the emissions, the latitude of the volcano, the season and large scale atmospheric circulations, also influence the climatic response. Complex couplings exist between stratospheric chemistry and circulations, and aerosol induced heating and aerosol microphysical processes such as condensation and evaporation. As yet, there has been no systematic assessment of these relationships when considering different eruption source parameters. A series of simulations with a global composition-climate model with interactive stratospheric chemistry and aerosol microphysics are conducted, in which the eruption latitude and injection height are varied. Parameter combinations are chosen such that injections sample areas in the atmosphere where different chemical and dynamical influences are important (e.g. tropical vs. high latitude eruptions, injections near the tropopause vs. injections in the upper stratosphere). Each experiment is repeated for varying SO2 injection magnitudes. We focus on the analysis of aerosol properties such as the stratospheric aerosol optical depth, effective radius and heating rates, and resultant perturbations to radiative fluxes. Initial results demonstrate the non-linearity in the climatic response as the injection magnitude is increased. Future work will focus on disentangling the contribution of each parameter to the climatic response with additional simulations to investigate the effect of season and the Quasi Biennial Oscillation. Results will aid in the understanding of the impact of past, present and future volcanic eruptions. By analysing sulfate deposition to the polar ice caps, we will assess the uncertainty in, and validity of, the historic volcanic radiative forcing deduced from ice cores.

  5. Potential control of climatic changes on flood events in the Yangtze Delta during 1100-2002

    Institute of Scientific and Technical Information of China (English)

    JIANGTong; ZHANGQiang; YvesGUERNOND

    2004-01-01

    Wide collection on the historic records of the climatic changes and flood events is performed in the Yangtze Delta. Man-Kendall (MK) method is applied to explore the changing trends of the time series of the flood discharge and the maximum high summer temperature. The research results indicate that the flood magnitudes increased during the transition from the medieval warm interval into the early Little Ice Age. Fluctuating climate changes of the Little Ice Age characterized by arid climate events followed by the humid and cold climate conditions give rise to the frequent flood hazards. Low-lying terrain made the study region prone to the flood hazards, storm fide and typhoon. MK analysis reveals that the jumping point of the time series of the flood discharge changes occurred in the mid-1960s, that of the maximum summer temperature changes in the mid-1990s, andthe exact jump point in 1993. The flood discharge changes are on negative trend before the 1990s, they are on positive tendency after the 1990s; the maximum high summer temperature changes are on negative trend before the 1990s and on positive tendency after the 1990s. These results indicate that the trend of flood discharge matches that of the maximum high summer temperature in the Yangtze Delta. The oecarrence probability of the maximum high summer temperature will be increasing under the climatic wanning scenario and which will in turn increase the oecarrence probability of the flood events. More active solar action epochs and the higher sea surface temperature index (SST index) ofthe south Pacific Ocean area lying between 4°N-4°S and 150°W-90°W correspond to increased annual precipitation, flood discharge and oecarrence frequency of floods in the Yangtze Delta. This is partly beeanse the intensified solar activities and the higher SST index give rise to accelerated hydrological circulation from ocean surface to the continent, resulting in increased precipitation on the continent.

  6. Transcription factor control of growth rate dependent genes in Saccharomyces cerevisiae: A three factor design

    DEFF Research Database (Denmark)

    Fazio, Alessandro; Jewett, Michael Christopher; Daran-Lapujade, Pascale;

    2008-01-01

    Background: Characterization of cellular growth is central to understanding living systems. Here, we applied a three-factor design to study the relationship between specific growth rate and genome-wide gene expression in 36 steady-state chemostat cultures of Saccharomyces cerevisiae. The three...... factors we considered were specific growth rate, nutrient limitation, and oxygen availability. Results: We identified 268 growth rate dependent genes, independent of nutrient limitation and oxygen availability. The transcriptional response was used to identify key areas in metabolism around which m...

  7. Tunable signal processing through modular control of transcription factor translocation

    Science.gov (United States)

    Hao, Nan; Budnik, Bogdan A.; Gunawardena, Jeremy; O’Shea, Erin K.

    2013-01-01

    Signaling pathways can induce different dynamics of transcription factor (TF) activation. We explored how TFs process signaling inputs to generate diverse dynamic responses. The budding yeast general stress responsive TF Msn2 acted as a tunable signal processor that could track, filter, or integrate signals in an input dependent manner. This tunable signal processing appears to originate from dual regulation of both nuclear import and export by phosphorylation, as mutants with one form of regulation sustained only one signal processing function. Versatile signal processing by Msn2 is crucial for generating distinct dynamic responses to different natural stresses. Our findings reveal how complex signal processing functions are integrated into a single molecule and provide a guide for the design of TFs with “programmable” signal processing functions. PMID:23349292

  8. Tunable signal processing through modular control of transcription factor translocation.

    Science.gov (United States)

    Hao, Nan; Budnik, Bogdan A; Gunawardena, Jeremy; O'Shea, Erin K

    2013-01-25

    Signaling pathways can induce different dynamics of transcription factor (TF) activation. We explored how TFs process signaling inputs to generate diverse dynamic responses. The budding yeast general stress-responsive TF Msn2 acted as a tunable signal processor that could track, filter, or integrate signals in an input-dependent manner. This tunable signal processing appears to originate from dual regulation of both nuclear import and export by phosphorylation, as mutants with one form of regulation sustained only one signal-processing function. Versatile signal processing by Msn2 is crucial for generating distinct dynamic responses to different natural stresses. Our findings reveal how complex signal-processing functions are integrated into a single molecule and provide a guide for the design of TFs with "programmable" signal-processing functions.

  9. Net ecosystem CO2 exchange and controlling factors in a steppe——Kobresia meadow on the Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    <正>Knowledge of seasonal variation of net ecosystem CO2 exchange (NEE) and its biotic and abiotic controllers will further our understanding of carbon cycling process, mechanism and large-scale modelling. Eddy covariance technique was used to measure NEE, biotic and abiotic factors for nearly 3 years in the hinterland alpine steppe--Korbresia meadow grassland on the Tibetan Plateau, the present highest fluxnet station in the world. The main objectives are to investigate dynamics of NEE and its components and to determine the major controlling factors. Maximum carbon assimilation took place in August and maximum carbon loss occurred in November. In June, rainfall amount due to monsoon climate played a great role in grass greening and consequently influenced interannual variation of ecosystem carbon gain. From July through September, monthly NEE presented net carbon assimilation. In other months, ecosystem exhibited carbon loss. In growing season, daytime NEE was mainly controlled by photosynthetically active radiation (PAR). In addition, leaf area index (LAI) interacted with PAR and together modulated NEE rates. Ecosystem respiration was controlled mainly by soil temperature and simultaneously by soil moisture. Q10 was negatively correlated with soil temperature but positively correlated with soil moisture. Large daily range of air temperature is not necessary to enhance carbon gain. Standard respiration rate at referenced 10℃(R10) was positively correlated with soil moisture, soil temperature, LAI and aboveground biomass. Rainfall patterns in growing season markedly influenced soil moisture and therefore soil moisture controlled seasonal change of ecosystem respiration. Pulse rainfall in the beginning and at the end of growing season induced great ecosystem respiration and consequently a great amount of carbon was lost. Short growing season and relative low temperature restrained alpine grass vegetation development. The results suggested that LAI be usually in

  10. INFLUENCE OF CLIMATE AND ENVIRONMENT FACTORS ON OUTDOOR FITNESS DESIGN%气候环境因素对室外健身设计的影响

    Institute of Scientific and Technical Information of China (English)

    马广韬; 毛琛

    2015-01-01

    This paper mainly studies the influence of climate and environment difference of outdoor exercise for people, providing analysis of environmental factors of climate science for outdoor exercise. Through the analysis of the differences between the north and south of climate and environment, the article tries to do research on climate environment differences in China for users and equipment outdoor fitness equipment itself. By analyzing the impact of climate factors on outdoor fitness, the article points out to make more secure, comfortable outdoor fitness.%本文主要研究气候环境差异对人们进行室外健身锻炼的影响,为室外健身锻炼提供科学的气候环境因素分析。通过对南北方气候环境差异的分析,研究我国气候环境差异对室外健身器材使用者和器材本身的影响,通过分析确定气候环境因素对室外健身的影响,使室外健身环境更加安全、舒适。

  11. J-Inner-Outer Factorization, J-Spectral Factorization, and Robust Control for Nonlinear Systems

    NARCIS (Netherlands)

    Ball, Joseph A.; Schaft, Arjan J. van der

    1996-01-01

    The problem of expressing a given nonlinear state-space system as the cascade connection of a lossless system and a stable, minimum-phase system (inner-outer factorization) is solved for the case of a stable system having state-space equations affine in the inputs. The solution is given in terms of

  12. Geographical distribution patterns of Macromitrium and Orthotrichum in China and their relationship with climatic factors

    Directory of Open Access Journals (Sweden)

    Yahong Ma

    2013-03-01

    Full Text Available A maximum entropy algorithm modelling program (MaxEnt 3.3.2 and a GIS software system (ArcGIS9.3 were used to study and model the distribution of 131 occurrences of Macromitrium and 66 occurrences of Orthotrichum in China in relation to 19 bioclimatic variables and percent tree cover. The information obtained can help predict the potential distribution range of these species in China, and also provide an understanding of factors influencing their current geographical distribution patterns so as to achieve better conservation of species diversity in the future. The species occurrence data were obtained from field work, relevant literature and herbarium specimens examined. Based on the integrated habitat suitability indices calculated, results show that Macromitrium have higher habitat suitability in the southeast and some southern provinces of China, i.e., in Zhejiang, Taiwan, Hainan, Fujian, Chongqing, and lower distribution probability in northwest, northeast and some northern provinces. Likewise, Orthotrichum has higher habitatsuitability in Yunnan, Beijing, Liaoning, Jilin, Guizhou, Shanxi, Sichuan and Hebei, and lower distributional probability in the southwest. The distribution probability of Macromitrium increases with increased annual precipitation, precipitation in the wettest month, and in both the coldest and wettest quarter of the year. The distribution probability of Orthotrichum increases rapidly with increasing annual precipitation upto 200 mm, and then decreases when annual precipitation exceeds 200 mm. The distribution probability of Orthotrichum reaches its highest peak when the mean temperature of the warmest quarter is between 15 and 20℃. The relationship between species number (Y of Macromitrium and annual rainfall (X1 is described by the equation Y = –0.0369+0.0003X1 (r = 0.5347, P<0.001, n = 131, and with the annual temperature (X2 by Y = 0.0831e0.001X2 (r = 0.5525, P<0.001, n = 131. The relationship between species

  13. The influence of soil-site factors on sugar maple (Acer saccharum Marsh.) growth response to climatic change in central Ontario

    Science.gov (United States)

    Schutten, K.; Gedalof, Z.

    2010-12-01

    Over the past several decades, concerns about climatic change and its potential impacts on Canada’s various geographical regions and associated ecological processes have grown steadily, especially among land and resource managers. As these risks transition into tangible outcomes in the field, it will be important for resource managers to understand historical climatic variability and natural ecological trends in order to effectively respond to a changing climate. Sugar maple (Acer saccharum Marsh.) is considered a stable endpoint for mature forests in the northern hardwood community of central Ontario, and it tends to be the dominant species, in a beech-ironwood-yellow birch matrix. In North America, this species is used for both hardwood lumber and for maple sugar (syrup) products; where it dominates, large recreational opportunities also exist. There are many biotic and abiotic factors that play a large role in the growth and productivity of sugar maple stands, such as soil pH, moisture regime, and site slope and aspect. This research undertaking aims to add to the body of literature addressing the following question: how do site factors influence the sensitivity of sugar maple growth to climatic change? The overall objective of the research is to evaluate how biotic and abiotic factors influence the sensitivity of sugar maple annual radial growth to climatic variability. This research will focus on sugar maple growth and productivity in Algonquin Provincial Park, and the impact that climatic variability has had in the past on these stands based on site-specific characteristics. In order to complete this goal, 20 sites were identified in Algonquin Provincial Park based on variability of known soil and site properties. These sites were visited in order to collect biotic and abiotic site data, and to measure annual radial growth increment of trees. Using regional climate records and standard dendrochronological methods, the collected increment growth data will be

  14. Analyzing the role of climatic factors on road accidents (Case study: Ardabil-Parsabad road in Ardabil Province, Iran

    Directory of Open Access Journals (Sweden)

    Sadegheh Alizadeh

    2014-07-01

    Full Text Available Road accidents and their fatalities are among the currentchallenges human society facing, which in turn resulting in huge social and economiccosts on the countries. Thedeveloping countries are the biggest victims of the road accidents such that inthese countries, road accidents are considered asthe major cause of death. Unfortunately, Iran is amongthe countries in which the rate of road accidents is high. Among thedriving factors that affect road safety and transport isclimate. Ardabil-Parsabad road in Ardabil province is one of the roads manyaccidents have been occurred during years, and thistrend began when the number of cars increased resulted in huge road deaths in1990s. In this study, data has been used from four meteorological stations inArdabil, Samian, Meshkin-Shahr and Parsabad, over a period of5years(2008-2002.For this purpose, several climatic elements werecollected including the average daily temperature, average of minimum temperatures,average of maximum temperatures, the number of snowy days, the number of frostdays, starting glacial period, duration of the snowfall, duration of theglacial period, total average humidity and moderate precipitation, average of sunnyhours, average number of foggy days, the average number of windy days. This analysis is provided using Excel software inthe Arc GIS environment of continuous levels of these parameters in the region.

  15. Intrinsic Factors Influencing the Infection by Helminth Parasites in Horses under an Oceanic Climate Area (NW Spain

    Directory of Open Access Journals (Sweden)

    I. Francisco

    2009-01-01

    Full Text Available A coprological survey to determine the influence of some intrinsic factors (breed, age, and sex on the infection by helminth parasites in equine livestock (n=418 under an oceanic climate area (NW Spain was conducted. Faecal samples were individually collected and analyzed by the coprological techniques. The main strongylid genera identified were Trichonema and Cyalocephalus spp (small strongyles and Strongylus and Triodontophorus (large strongyles. The prevalence of gastrointestinal nematode was 89% (95% CI 86, 92 and 1% cestoda (0, 2. The percentage of horses with strongyloid parasites was 89% (86, 92, 11% (8, 14 for Parascaris, and 3% (1, 5 for Oxyuris. The highest prevalence for ascariosis was observed in the youngest horses (10 years animals, and for strongylosis in the 3–10 years ones. Females were significantly more parasitized than males. A negative correlation between the age and the egg-excretion of ascarids and strongyles was recorded. The autochthonous and the English Pure Blood horses were the most parasitized. We concluded that the infections by helminths, especially the strongyloids, are significantly common in the region, so that greater importance should be given to this situation.

  16. Intrinsic Factors Influencing the Infection by Helminth Parasites in Horses under an Oceanic Climate Area (NW Spain).

    Science.gov (United States)

    Francisco, I; Arias, M; Cortiñas, F J; Francisco, R; Mochales, E; Dacal, V; Suárez, J L; Uriarte, J; Morrondo, P; Sánchez-Andrade, R; Díez-Baños, P; Paz-Silva, A

    2009-01-01

    A coprological survey to determine the influence of some intrinsic factors (breed, age, and sex) on the infection by helminth parasites in equine livestock (n = 418) under an oceanic climate area (NW Spain) was conducted. Faecal samples were individually collected and analyzed by the coprological techniques. The main strongylid genera identified were Trichonema and Cyalocephalus spp (small strongyles) and Strongylus and Triodontophorus (large strongyles). The prevalence of gastrointestinal nematode was 89% (95% CI 86, 92) and 1% cestoda (0, 2). The percentage of horses with strongyloid parasites was 89% (86, 92), 11% (8, 14) for Parascaris, and 3% (1, 5) for Oxyuris. The highest prevalence for ascariosis was observed in the youngest horses (10 years animals, and for strongylosis in the 3-10 years ones.