WorldWideScience

Sample records for atmospheric greenhouse effect

  1. Greenhouse effect in the atmosphere

    Science.gov (United States)

    Smirnov, B. M.

    2016-04-01

    Average optical atmospheric parameters for the infrared spectrum range are evaluated on the basis of the Earth energetic balance and parameters of the standard atmosphere. The average optical thickness of the atmosphere is u ≈ 2.5 and this atmospheric emission is originated at altitudes below 10 km. Variations of atmospheric radiative fluxes towards the Earth and outward are calculated as a function of the concentration of \\text{CO}2 molecules for the regular model of molecular spectrum. As a result of doubling of the \\text{CO}2 concentration the change of the global Earth temperature is (0.4 +/- 0.2) \\text{K} if other atmospheric parameters are conserved compared to the value (3.0 +/- 1.5) \\text{K} under real atmospheric conditions with the variation of the amount of atmospheric water. An observed variation of the global Earth temperature during the last century (0.8 ^\\circ \\text{C}) follows from an increase of the mass of atmospheric water by 7% or by conversion of 1% of atmospheric water in aerosols.

  2. Greenhouse effect due to atmospheric nitrous oxide

    Science.gov (United States)

    Yung, Y. L.; Wang, W. C.; Lacis, A. A.

    1976-01-01

    The greenhouse effect due to nitrous oxide in the present atmosphere is about 0.8 K. Increase in atmospheric N2O due to perturbation of the nitrogen cycle by man may lead to an increase in surface temperature as large as 0.5 K by 2025, or 1.0 K by 2100. Other climatic effects of N2O are briefly discussed.

  3. Effect of noble gases on an atmospheric greenhouse /Titan/.

    Science.gov (United States)

    Cess, R.; Owen, T.

    1973-01-01

    Several models for the atmosphere of Titan have been investigated, taking into account various combinations of neon and argon. The investigation shows that the addition of large amounts of Ne and/or Ar will substantially reduce the hydrogen abundance required for a given greenhouse effect. The fact that a large amount of neon should be present if the atmosphere is a relic of the solar nebula is an especially attractive feature of the models, because it is hard to justify appropriate abundances of other enhancing agents.

  4. Greenhouse effect dependence on atmospheric concentrations of greenhouse substances and the nature of climate stability on Earth

    Directory of Open Access Journals (Sweden)

    V. G. Gorshkov

    2002-03-01

    Full Text Available Due to the exponential positive feedback between sea surface temperature and saturated water vapour concentration, dependence of the planetary greenhouse effect on atmospheric water content is critical for stability of a climate with extensive liquid hydrosphere.

    In this paper on the basis of the law of energy conservation we develop a simple physically transparent approach to description of radiative transfer in an atmosphere containing greenhouse substances. It is shown that the analytical solution of the equation thus derived coincides with the exact solution of the well-known radiative transfer equation to the accuracy of 20% for all values of atmospheric optical depth. The derived equation makes it possible to easily take into account the non-radiative thermal fluxes (convection and latent heat and obtain an analytical dependence of the greenhouse effect on atmospheric concentrations of a set of greenhouse substances with arbitrary absorption intervals.

    The established dependence is used to analyse stability of the modern climate of Earth. It is shown that the modern value of global mean surface temperature, which corresponds to the liquid state of the terrestrial hydrosphere, is physically unstable. The observed stability of modern climate over geological timescales is therefore likely to be due to dynamic singularities in the physical temperature-dependent behaviour of the greenhouse effect. We hypothesise that such singularities may appear due to controlling functioning of the natural global biota and discuss major arguments in support of this conclusion.

  5. Emission of carbon. A most important component for greenhouse effect in the atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Milaev, V.B.; Kopp, I.Z.; Yasenski, A.N. [Scientific Research Inst. of Atmospheric Air Protection, St. Petersburg (Russian Federation)

    1995-12-31

    Greenhouse effect is most often defined as the probabilities of atmospheric air quasiequilibrium temperature increase as a result of air pollution due to emission of anthropogenic gaseous substances which are usually called `greenhouse gases`. Among greenhouse gases are primarily considered several gaseous substances which contain carbon atoms: carbon oxide, carbon dioxide and methane (CO, CO{sub 2} and CH{sub 4}), and chlorinated and fluorinated hydrocarbons (freons) spectra of which are transparent to solar radiation, but absorb and reradiate longwave radiation causing disturbance of quasistationary thermal regieme of the atmosphere. Qualitative estimates of the income and relative roles of different substances in occurrence of greenhouse effect differ considerable. At the modern state of knowledge the problem of greenhouse effect and greenhouse gases is considered in several aspects. The most widespread and investigated is climatic or meteorological aspect, it is discussed in a number of international works. Rather pressing is thermal physics aspect of the problem of estimating greenhouse effect, which consists in correct construction of a calculation model and usage of the most representative experimental data, since analytical methods require many assumptions, introduction of which may lead to results which differ very much. Bearing these uncertainties in mind the UNEP/WMO/ICSU conference has included into the number of the most urgent tasks in the study of greenhouse effect, the problem of determining the priority of factors which cause greenhouse effect, which in its turn predetermines the necessity to substantiate the methods of selection and criterion of comparative evaluation of such factors. (author)

  6. The greenhouse effect in a gray planetary atmosphere.

    Science.gov (United States)

    Wildt, R.

    1966-01-01

    Hopf analytical solution for values of ratio of gray absorption coefficients for insolating and escaping radiation /greenhouse parameter/ assumed constant at all depths, presenting temperature distribution graphs

  7. Falsification Of The Atmospheric CO2 Greenhouse Effects Within The Frame Of Physics

    CERN Document Server

    Gerlich, Gerhard

    2007-01-01

    The atmospheric greenhouse effect, an idea that authors trace back to the traditional works of Fourier 1824, Tyndall 1861 and Arrhenius 1896 and is still supported in global climatology essentially describes a fictitious mechanism in which a planetary atmosphere acts as a heat pump driven by an environment that is radiatively interacting with but radiatively equilibrated to the atmospheric system. According to the second law of thermodynamics such a planetary machine can never exist. Nevertheless, in almost all texts of global climatology and in a widespread secondary literature it is taken for granted that such mechanism is real and stands on a firm scientific foundation. In this paper the popular conjecture is analyzed and the underlying physical principles are clarified. By showing that (a) there are no common physical laws between the warming phenomenon in glass houses and the fictitious atmospheric greenhouse effects, (b) there are no calculations to determine an average surface temperature of a planet, ...

  8. The increased atmospheric greenhouse effect and regional climate change

    Energy Technology Data Exchange (ETDEWEB)

    Groenaas, S. [Bergen Univ. (Norway)

    1996-03-01

    This paper was read at the workshop ``The Norwegian Climate and Ozone Research Programme`` held on 11-12 March 1996. The main information for predicting future climate changes comes from integrating coupled climate models of the atmosphere, ocean and cryosphere. Regional climate change may be studied from the global integrations, however, resolution is coarse because of insufficient computer power. Attempts are being made to get more regional details out of the global integrations by ``downscaling`` the latter. This can be done in two ways. Firstly, limited area models with high resolution are applied, driven by the global results as boundary values. Secondly, statistical relationships have been found between observed meteorological parameters, like temperature and precipitation, and analyzed large scale gridded fields. The derived relations are then used on similar data from climate runs to give local interpretations. A review is given of literature on recent observations of climate variations and on predicted regional climate change. 18 refs., 4 figs.

  9. Soil greenhouse gas emissions reduce the contribution of mangrove plants to the atmospheric cooling effect

    Science.gov (United States)

    Chen, Guangcheng; Chen, Bin; Yu, Dan; Tam, Nora F. Y.; Ye, Yong; Chen, Shunyang

    2016-12-01

    Mangrove soils have been recognized as sources of greenhouse gases, but the atmospheric fluxes are poorly characterized, and their adverse warming effect has rarely been considered with respect to the potential contribution of mangrove wetlands to climate change mitigation. The current study balanced the warming effect of soil greenhouse gas emissions with the plant carbon dioxide (CO2) sequestration rate derived from the plants’ net primary production in a productive mangrove wetland in South China to assess the role of mangrove wetlands in reducing the atmospheric warming effect. Soil characteristics were also studied in the summer to examine their relationships with gas fluxes. The soil to atmosphere fluxes of nitrous oxide (N2O), methane (CH4) and CO2 ranged from -1.6 to 50.0 μg m-2 h-1, from -1.4 to 5360.1 μg m-2 h-1 and from -31 to 512 mg m-2 h-1, respectively, which indicated that the mangrove soils act as sources of greenhouse gases in this area. The gas fluxes were higher in summer than in the cold seasons and were variable across mangrove sites. Gas fluxes in summer were positively correlated with the soil organic carbon, total nitrogen, and ammonia contents. The mangrove plants sequestered a considerable amount of atmospheric CO2 at rates varying from 3652 to 7420 g CO2 m-2 yr-1. The ecosystem acted as a source of CH4 and N2O gases but was a more intense CO2 sink. However, the warming effect of soil gas emissions accounted for 9.3-32.7% of the plant CO2 sequestration rate, partially reducing the benefit of mangrove plants, and the two trace gases comprised 9.7-33.2% of the total warming effect. We therefore propose that an assessment of the reduction of atmospheric warming effects by a mangrove ecosystem should consider both soil greenhouse gas emissions and plant CO2 sequestration.

  10. Global warming: Experimental study about the effect of accumulation of greenhouse gases in the atmosphere

    Science.gov (United States)

    Molto, Carlos; Mas, Miquel

    2010-05-01

    The project presented here was developed by fifteen year old students of the Institut Sabadell (Sabadell Secondary School. Spain). The objective of this project was to raise the students awareness' about the problem of climate change, mainly caused by the accumulation of greenhouse gases in the atmosphere. It is also intended that students use the scientific method as an effective system of troubleshooting and that they use the ICTs (Information and Communication Technologies) to elicit data and process information. To develop this project, four lessons of sixty minutes each were needed. The first lesson sets out the role of the atmosphere as an Earth's temperature regulator, highlighting the importance of keeping the levels of carbon dioxide, methane and water steam in balance. The second lesson is focused on the experimental activity that students will develop in the following lesson. In lesson two, students will present and justify their hypothesis about the experiment. Some theoretical concepts, necessary to carry out the experiment, will also be explained. The third lesson involves the core of the project, that is the experiment in the laboratory. The experiment consists on performing the atmosphere heating on a little scale. Four different atmospheres are created inside four plastic boxes heated by an infrared lamp. Students work in groups (one group for each atmosphere) and have to monitor the evolution of temperature by means of a temperature sensor (Multilog software). The first group has to observe the relationship between temperature and carbon dioxide levels increase, mainly caused by the widespread practice of burning fossil fuels by growing human populations. The task of this group is to measure simultaneously the temperature of an empty box (without CO2) and the temperature of a box with high carbon dioxide concentration. The carbon dioxide concentration is the result of the chemical reaction when sodium carbonate mixes with hydrochloric acid. The

  11. Ammonia photolysis and the greenhouse effect in the primordial atmosphere of the earth

    Science.gov (United States)

    Kuhn, W. R.; Atreya, S. K.

    1979-01-01

    Photochemical calculations indicate that in the prebiotic atmosphere of earth ammonia would have been irreversibly converted to N2 in less than 40 years if the ammonia surface mixing ratio were no more than 0.0001. However, if a continuous outgassing of ammonia were maintained, radiative-equilibrium calculations indicate that a surface mixing ratio of ammonia of 0.0001 or greater would provide a sufficient greenhouse effect to keep the surface temperature above freezing. With a 0.0001 mixing ratio of ammonia, 60% to 70% of the present-day solar luminosity would be adequate to maintain surface temperatures above freezing. A lower limit to the time constant for accumulation of an amount of nitrogen equivalent to the present day value is 10 my if the outgassing were such as to provide a continuous surface mixing ratio of ammonia of at least 0.00001.

  12. Clouds in the atmospheres of extrasolar planets. IV. On the scattering greenhouse effect of CO2 ice particles: Numerical radiative transfer studies

    CERN Document Server

    Kitzmann, D; Rauer, H

    2013-01-01

    Owing to their wavelengths dependent absorption and scattering properties, clouds have a strong impact on the climate of planetary atmospheres. Especially, the potential greenhouse effect of CO2 ice clouds in the atmospheres of terrestrial extrasolar planets is of particular interest because it might influence the position and thus the extension of the outer boundary of the classic habitable zone around main sequence stars. We study the radiative effects of CO2 ice particles obtained by different numerical treatments to solve the radiative transfer equation. The comparison between the results of a high-order discrete ordinate method and simpler two-stream approaches reveals large deviations in terms of a potential scattering efficiency of the greenhouse effect. The two-stream methods overestimate the transmitted and reflected radiation, thereby yielding a higher scattering greenhouse effect. For the particular case of a cool M-type dwarf the CO2 ice particles show no strong effective scattering greenhouse eff...

  13. On the relationship between the greenhouse effect, atmospheric photochemistry, and species distribution

    Science.gov (United States)

    Callis, L. B.; Boughner, R. E.; Natarajan, M.

    1983-01-01

    The coupling that exists between infrared opacity changes and tropospheric (and to a lesser extent stratospheric) chemistry is explored in considerable detail, and the effects arising from various perturbations are examined. The studies are carried out with a fully coupled one-dimensional radiative-convective-photochemical model (RCP) that extends from the surface to 53.5 km and has the capability of calculating surface temperature changes due to both chemical and radiative perturbations. The model encompasses contemporary atmospheric chemistry and photochemistry involving the O(x), HO(x), NO(x), and Cl(x) species.

  14. Atmospheric Chemistry and Greenhouse Gases

    Energy Technology Data Exchange (ETDEWEB)

    Ehhalt, D.; Prather, M.; Dentener, F.; Derwent, R.; Dlugokencky, Edward J.; Holland, E.; Isaksen, I.; Katima, J.; Kirchhoff, V.; Matson, P.; Midgley, P.; Wang, M.; Berntsen, T.; Bey, I.; Brasseur, G.; Buja, L.; Collins, W. J.; Daniel, J. S.; DeMore, W. B.; Derek, N.; Dickerson, R.; Etheridge, D.; Feichter, J.; Fraser, P.; Friedl, R.; Fuglestvedt, J.; Gauss, M.; Grenfell, L.; Grubler, Arnulf; Harris, N.; Hauglustaine, D.; Horowitz, L.; Jackman, C.; Jacob, D.; Jaegle, L.; Jain, Atul K.; Kanakidou, M.; Karlsdottir, S.; Ko, M.; Kurylo, M.; Lawrence, M.; Logan, J. A.; Manning, M.; Mauzerall, D.; McConnell, J.; Mickley, L. J.; Montzka, S.; Muller, J. F.; Olivier, J.; Pickering, K.; Pitari, G.; Roelofs, G.-J.; Rogers, H.; Rognerud, B.; Smith, Steven J.; Solomon, S.; Staehelin, J.; Steele, P.; Stevenson, D. S.; Sundet, J.; Thompson, A.; van Weele, M.; von Kuhlmann, R.; Wang, Y.; Weisenstein, D. K.; Wigley, T. M.; Wild, O.; Wuebbles, D.J.; Yantosca, R.; Joos, Fortunat; McFarland, M.

    2001-10-01

    Chapter 4 of the IPCC Third Assessment Report Climate Change 2001: The Scientific Basis. Sections include: Executive Summary 2414.1 Introduction 2434.2 Trace Gases: Current Observations, Trends and Budgets 2484.3 Projections of Future Emissions 2664.4 Projections of Atmospheric Composition for the 21st Century 2674.5 Open Questions 2774.6 Overall Impact of Global Atmospheric Chemistry Change 279

  15. Observational determination of the greenhouse effect

    Science.gov (United States)

    Raval, A.; Ramanathan, V.

    1989-01-01

    Satellite measurements are used to quantify the atmospheric greenhouse effect, defined here as the infrared radiation energy trapped by atmospheric gases and clouds. The greenhouse effect is found to increase significantly with sea surface temperature. The rate of increase gives compelling evidence for the positive feedback between surface temperature, water vapor and the greenhouse effect; the magnitude of the feedback is consistent with that predicted by climate models. This study demonstrates an effective method for directly monitoring, from space, future changes in the greenhouse effect.

  16. A Hiatus of the Greenhouse Effect.

    Science.gov (United States)

    Song, Jinjie; Wang, Yuan; Tang, Jianping

    2016-09-12

    The rate at which the global average surface temperature is increasing has slowed down since the end of the last century. This study investigates whether this warming hiatus results from a change in the well-known greenhouse effect. Using long-term, reliable, and consistent observational data from the Earth's surface and the top of the atmosphere (TOA), two monthly gridded atmospheric and surface greenhouse effect parameters (Ga and Gs) are estimated to represent the radiative warming effects of the atmosphere and the surface in the infrared range from 1979 to 2014. The atmospheric and surface greenhouse effect over the tropical monsoon-prone regions is found to contribute substantially to the global total. Furthermore, the downward tendency of cloud activity leads to a greenhouse effect hiatus after the early 1990 s, prior to the warming pause. Additionally, this pause in the greenhouse effect is mostly caused by the high number of La Niña events between 1991 and 2014. A strong La Niña indicates suppressed convection in the tropical central Pacific that reduces atmospheric water vapor content and cloud volume. This significantly weakened regional greenhouse effect offsets the enhanced warming influence in other places and decelerates the rising global greenhouse effect. This work suggests that the greenhouse effect hiatus can be served as an additional factor to cause the recent global warming slowdown.

  17. A Hiatus of the Greenhouse Effect

    Science.gov (United States)

    Song, Jinjie; Wang, Yuan; Tang, Jianping

    2016-09-01

    The rate at which the global average surface temperature is increasing has slowed down since the end of the last century. This study investigates whether this warming hiatus results from a change in the well-known greenhouse effect. Using long-term, reliable, and consistent observational data from the Earth’s surface and the top of the atmosphere (TOA), two monthly gridded atmospheric and surface greenhouse effect parameters (Ga and Gs) are estimated to represent the radiative warming effects of the atmosphere and the surface in the infrared range from 1979 to 2014. The atmospheric and surface greenhouse effect over the tropical monsoon-prone regions is found to contribute substantially to the global total. Furthermore, the downward tendency of cloud activity leads to a greenhouse effect hiatus after the early 1990 s, prior to the warming pause. Additionally, this pause in the greenhouse effect is mostly caused by the high number of La Niña events between 1991 and 2014. A strong La Niña indicates suppressed convection in the tropical central Pacific that reduces atmospheric water vapor content and cloud volume. This significantly weakened regional greenhouse effect offsets the enhanced warming influence in other places and decelerates the rising global greenhouse effect. This work suggests that the greenhouse effect hiatus can be served as an additional factor to cause the recent global warming slowdown.

  18. (Limiting the greenhouse effect)

    Energy Technology Data Exchange (ETDEWEB)

    Rayner, S.

    1991-01-07

    Traveler attended the Dahlem Research Conference organized by the Freien Universitat, Berlin. The subject of the conference was Limiting the Greenhouse Effect: Options for Controlling Atmospheric CO{sub 2} Accumulation. Like all Dahlem workshops, this was a meeting of scientific experts, although the disciplines represented were broader than usual, ranging across anthropology, economics, international relations, forestry, engineering, and atmospheric chemistry. Participation by scientists from developing countries was limited. The conference was divided into four multidisciplinary working groups. Traveler acted as moderator for Group 3 which examined the question What knowledge is required to tackle the principal social and institutional barriers to reducing CO{sub 2} emissions'' The working rapporteur was Jesse Ausubel of Rockefeller University. Other working groups examined the economic costs, benefits, and technical feasibility of options to reduce emissions per unit of energy service; the options for reducing energy use per unit of GNP; and the significant of linkage between strategies to reduce CO{sub 2} emissions and other goals. Draft reports of the working groups are appended. Overall, the conference identified a number of important research needs in all four areas. It may prove particularly important in bringing the social and institutional research needs relevant to climate change closer to the forefront of the scientific and policy communities than hitherto.

  19. The Greenhouse and Anti-Greenhouse Effects on Titan

    Science.gov (United States)

    McKay, C. P.; Cuzzi, Jeffrey N. (Technical Monitor)

    1994-01-01

    Titan is the largest moon of Saturn and is the only moon in the solar system with a substantial atmosphere. Its atmosphere is mostly made of nitrogen, with a few percent CH4, 0.1% H2 and an uncertain level of Ar (less than 10%). The surface pressure is 1.5 atms and the surface temperature is 95 K, decreasing to 71 at the tropopause before rising to stratospheric temperatures of 180 K. In pressure and composition Titan's atmosphere is the closest twin to Earth's. The surface of Titan remains unknown, hidden by the thick smog layer, but it may be an ocean of liquid methane and ethane. Titan's atmosphere has a greenhouse effect which is much stronger than the Earth's - 92% of the surface warming is due to greenhouse radiation. However an organic smog layer in the upper atmosphere produces an anti-greenhouse effect that cuts the greenhouse warming in half - removing 35% of the incoming solar radiation. Models suggest that during its formation Titan's atmosphere was heated to high temperatures due to accretional energy. This was followed by a cold Triton-like period which gradually warmed to the present conditions. The coupled greenhouse and haze anti-greenhouse may be relevant to recent suggestions for haze shielding of a CH4 - NH3 early atmosphere on Earth or Mars. When the NASA/ESA mission to the Saturn System, Cassini, launches in a few years it will carry a probe that will be sent to the surface of Titan and show us this world that is strange and yet in many ways similar to our own.

  20. Titan's greenhouse and antigreenhouse effects

    Science.gov (United States)

    Mckay, Christopher P.; Pollack, James B.; Courtin, Regis

    1992-01-01

    Thermal mechanisms active in Titan's atmosphere are discussed in a brief review of data obtained during the Voyager I flyby in 1980. Particular attention is given to the greenhouse effect (GHE) produced by atmospheric H2, N2, and CH4; this GHE is stronger than that on earth, with CH4 and H2 playing roles similar to those of H2O and CO2 on earth. Also active on Titan is an antigreenhouse effect, in which dark-brown and orange organic aerosols block incoming solar light while allowing IR radiation from the Titan surface to escape. The combination of GHE and anti-GHE leads to a surface temperature about 12 C higher than it would be if Titan had no atmosphere.

  1. The Greenhouse Effect and Climate Feedbacks

    Science.gov (United States)

    Covey, C.; Haberle, R. M.; McKay, C. P.; Titov, D. V.

    This chapter reviews the theory of the greenhouse effect and climate feedback. It also compares the theory with observations, using examples taken from all four known terrestrial worlds with substantial atmospheres: Venus, Earth, Mars, and Titan. The greenhouse effect traps infrared radiation in the atmosphere, thereby increasing surface temperature. It is one of many factors that affect a world's climate. (Others include solar luminosity and the atmospheric scattering and absorption of solar radiation.) A change in these factors — defined as climate forcing — may change the climate in a way that brings other processes — defined as feedbacks — into play. For example, when Earth's atmospheric carbon dioxide increases, warming the surface, the water vapor content of the atmosphere increases. This is a positive feedback on global warming because water vapor is itself a potent greenhouse gas. Many positive and negative feedback processes are significant in determining Earth's climate, and probably the climates of our terrestrial neighbors.

  2. The greenhouse and antigreenhouse effects on Titan

    Science.gov (United States)

    Mckay, Christopher P.; Pollack, James B.; Courtin, Regis

    1991-01-01

    The parallels between the atmospheric thermal structure of the Saturnian satellite Titan and the hypothesized terrestrial greenhouse effect can serve as bases for the evaluation of competing greenhouse theories. Attention is presently drawn to the similarity between the roles of H2 and CH4 on Titan and CO2 and H2O on earth. Titan also has an antigreenhouse effect due to a high-altitude haze layer which absorbs at solar wavelengths, while remaining transparent in the thermal IR; if this haze layer were removed, the antigreenhouse effect would be greatly reduced, exacerbating the greenhouse effect and raising surface temperature by over 20 K.

  3. Greenhouse effect due to chlorofluorocarbons - Climatic implications

    Science.gov (United States)

    Ramanathan, V.

    1975-01-01

    The infrared bands of chlorofluorocarbons and chlorocarbons enhance the atmospheric greenhouse effect. This enhancement may lead to an appreciable increase in the global surface temperature if the atmospheric concentrations of these compounds reach values of the order of 2 parts per billion.

  4. The earth's radiation budget and its relation to atmospheric hydrology. I - Observations of the clear sky greenhouse effect. II - Observations of cloud effects

    Science.gov (United States)

    Stephens, Graeme L.; Greenwald, Thomas J.

    1991-01-01

    The clear-sky components of the earth's radiation budget (ERB), the relationship of these components to the sea surface temperature (SST), and microwave-derived water-vapor amount are analyzed in an observational study along with the relationship between the cloudy-sky components of ERB and space/time coincident observations of SST, microwave-derived cloud liquid water, and cloud cover. The purpose of the study is to use these observations for establishing an understanding of the couplings between radiation and the atmosphere that are important to understanding climate feedback. A strategy for studying the greenhouse effect of earth by analyzing the emitted clear-sky longwave flux over the ocean is proposed. It is concluded that the largest observed influence of clouds on ERB is more consistent with macrophysical properties of clouds as opposed to microphysical properties. The analysis for clouds and the greenhouse effect of clouds is compared quantitatively with the clear sky results. Land-ocean differences and tropical-midlatitude differences are shown and explained in terms of the cloud macrostructure.

  5. Effects of ploughing on land-atmosphere exchange of greenhouse gases in a managed temperate grassland in central Scotland

    Science.gov (United States)

    Helfter, Carole; Drewer, Julia; Anderson, Margaret; Scholtes, Bob; Rees, Bob; Skiba, Ute

    2015-04-01

    Grasslands are important ecosystems covering > 20% and > 30% of EU and Scotland's land area respectively. Management practices such as grazing, fertilisation and ploughing can have significant short- and long-term effects on greenhouse gas exchange. Here we report on two separate ploughing events two years apart in adjacent grasslands under common management. The Easter Bush grassland, located 10 km south of Edinburgh (55° 52'N, 3° 2'W), comprises two fields separated by a fence and is used for grazing by sheep and cattle. The vegetation is predominantly Lolium perenne (> 90%) growing on poorly drained clay loam. The fields receive several applications of mineral fertiliser a year in spring and summer. Net ecosystem exchange (NEE) of carbon dioxide (CO2) has been monitored continuously by eddy-covariance (EC) since 2002 which has demonstrated that the site is a consistent yet variable sink of atmospheric CO2. The EC system comprises a LI-COR 7000 closed-path analyser and a Gill Instruments Windmaster Pro ultrasonic anemometer mounted atop a 2.5 m mast located along the fence line separating the fields. In addition, fluxes of nitrous oxide (N2O), methane (CH4)and CO2were measured with static chambers installed along transects in each field. Gas samples collected from the chambers were analysed by gas chromatography and fluxes calculated for each 60-minute sampling period. The ploughing events in 2012 and 2014 exhibited multiple similarities in terms of NEE. The light response (i.e. relationship between CO2 flux, and photosynthetically active radiation, PAR) of the NF and SF during the month preceding each ploughing event was of comparable magnitude in both years. Following ploughing, CO2 uptake ceased in the ploughed field for approximately one month and full recovery of the photosynthetic potential was observed after ca. 2 months. During the month following the 2014 ploughing event, the ploughed NF released on average 333 ± 17 mg CO2-C m-2 h-1. In contrast, the

  6. A new opinion of the greenhouse effect

    Directory of Open Access Journals (Sweden)

    Valery P. Oktyabrskiy

    2016-06-01

    Full Text Available The article analyzes the correspondence between the actually occurring physical and chemical processes and the concept of the greenhouse effect. The absorption of the solar radiation by the gases existing in the Earth's atmosphere has been examined. It was demonstrated that, despite the absorption of radiation from the Earth's surface in the middle and long-wave infrared (IR regions, there is a strong absorption of the overtones and combined frequencies of water vapor in the solar radiation (visible and near IR regions, i.e., the transmittance bandwidth of ‘the glass greenhouse’. Thus, the Earth atmosphere does not really function as a greenhouse, and the terms ‘greenhouse effect’ and ‘greenhouse gases’ lost their original meaning and have remained symbolical.

  7. 大气温室效应的一维辐射传热分析%One Dimensional Radiative Heat Transfer Analysis of Atmosphere Greenhouse Effects

    Institute of Scientific and Technical Information of China (English)

    刘彬; 帅永; 谈和平

    2011-01-01

    大气中温室气体对地面长波热辐射的吸收和再发射导致了温室效应.计算了大气不同高度200~50000 cm-1(0.2~50 μm)光谱吸收系数,采用一维大气介质模型和射线踪迹-节点分析法(RTNAM)的多层模型对大气中二氧化碳及水蒸气不同浓度情况下的大气温度进行了计算.结果表明标准大气CO2浓度增加1倍,对流层的温度上升0.453°C,若水蒸气浓度降低,CO2的温室效应更加明显.%Greenhouse gases absorb the thermal radiation from earth surface and reemit part of energy back. This progress leads to the greenhouse effects. Absorption coefficients at different latitude were calculated form 200 cm-1 to 50000 cm- 1(0.2~50μm). Using a one-dimensional radiative heat transfer model for atmosphere combined with multilayered model by Ray-Tracing/Nodal-Analyzing Method (RTNAM), atmospheric temperature fields were calculated under different CO2 and/or H2O concentration conditions. The results show that temperature in troposphere rise 0.453℃ if doubling of CO2Concentration, and if the concentration of H2O is lower, greenhouse effects of CO2 become more obvious.

  8. Greenhouse Effect Detection Experiment (GEDEX). Selected data sets

    Science.gov (United States)

    Olsen, Lola M.; Warnock, Archibald, III

    1992-01-01

    This CD-ROM contains selected data sets compiled by the participants of the Greenhouse Effect Detection Experiment (GEDEX) workshop on atmospheric temperature. The data sets include surface, upper air, and/or satellite-derived measurements of temperature, solar irradiance, clouds, greenhouse gases, fluxes, albedo, aerosols, ozone, and water vapor, along with Southern Oscillation Indices and Quasi-Biennial Oscillation statistics.

  9. Biomarker response to galactic cosmic ray-induced NOx and the methane greenhouse effect in the atmosphere of an Earth-like planet orbiting an M dwarf star.

    Science.gov (United States)

    Grenfell, John Lee; Griessmeier, Jean-Mathias; Patzer, Beate; Rauer, Heike; Segura, Antigona; Stadelmann, Anja; Stracke, Barbara; Titz, Ruth; Von Paris, Philip

    2007-02-01

    Planets orbiting in the habitable zone of M dwarf stars are subject to high levels of galactic cosmic rays (GCRs), which produce nitrogen oxides (NOx) in Earth-like atmospheres. We investigate to what extent these NO(Mx) species may modify biomarker compounds such as ozone (O3) and nitrous oxide (N2O), as well as related compounds such as water (H2O) (essential for life) and methane (CH4) (which has both abiotic and biotic sources). Our model results suggest that such signals are robust, changing in the M star world atmospheric column due to GCR NOx effects by up to 20% compared to an M star run without GCR effects, and can therefore survive at least the effects of GCRs. We have not, however, investigated stellar cosmic rays here. CH4 levels are about 10 times higher on M star worlds than on Earth because of a lowering in hydroxyl (OH) in response to changes in the ultraviolet. The higher levels of CH4 are less than reported in previous studies. This difference arose partly because we used different biogenic input. For example, we employed 23% lower CH4 fluxes compared to those studies. Unlike on Earth, relatively modest changes in these fluxes can lead to larger changes in the concentrations of biomarker and related species on the M star world. We calculate a CH4 greenhouse heating effect of up to 4K. O3 photochemistry in terms of the smog mechanism and the catalytic loss cycles on the M star world differs considerably compared with that of Earth.

  10. Effect of greenhouse gas emissions on stratospheric ozone depletion

    OpenAIRE

    Velders GJM; LLO

    1997-01-01

    The depletion of the ozone layer is caused mainly by the increase in emissions of chlorine- and bromine-containing compounds like CFCs, halons, carbon tetrachloride, methyl chloroform and methyl bromide. Emissions of greenhouse gases can affect the depletion of the ozone layer through atmospheric interaction. We studied the interactions in the atmosphere between the greenhouse effect and stratospheric ozone depletion from the point of view of past and future emissions of the anthropogenic com...

  11. (Limiting the greenhouse effect)

    Energy Technology Data Exchange (ETDEWEB)

    Fulkerson, W.

    1991-01-10

    The Dahlem Conference on controlling CO{sub 2} in the atmosphere focused on research needs broadly defined. The RD D needs discussed tended to be social-institutional rather than technically oriented perhaps because of the propensity of most attendees, but many important ideas emerged, including those related to questions on technology adoption by both developed, emerging, or transition economics. The European attendees appeared to be strongly devoted to reducing emissions, and doing it soon using efficiency improvement and ultimately renewables. The importance of efficiency improvement was universally accepted, but the extent to which it can be relied upon is a major uncertainty for everyone except the most zealous. There was no detailed discussion of what could be done to encourage the more rapid adoption of renewables. Most attendees seemed to have discounted nuclear, but, at any rate, the problems of reviving nuclear worldwide were not discussed in detail.

  12. Habitability of waterworlds: runaway greenhouses, atmospheric expansion, and multiple climate states of pure water atmospheres.

    Science.gov (United States)

    Goldblatt, Colin

    2015-05-01

    There are four different stable climate states for pure water atmospheres, as might exist on so-called "waterworlds." I map these as a function of solar constant for planets ranging in size from Mars-sized to 10 Earth-mass. The states are as follows: globally ice covered (Ts ⪅ 245 K), cold and damp (270 ⪅ Ts ⪅ 290 K), hot and moist (350 ⪅ Ts ⪅ 550 K), and very hot and dry (Tsx2A86;900 K). No stable climate exists for 290 ⪅ T s ⪅ 350 K or 550 ⪅ Ts ⪅ 900 K. The union of hot moist and cold damp climates describes the liquid water habitable zone, the width and location of which depends on planet mass. At each solar constant, two or three different climate states are stable. This is a consequence of strong nonlinearities in both thermal emission and the net absorption of sunlight. Across the range of planet sizes, I account for the atmospheres expanding to high altitudes as they warm. The emitting and absorbing surfaces (optical depth of unity) move to high altitude, making their area larger than the planet surface, so more thermal radiation is emitted and more sunlight absorbed (the former dominates). The atmospheres of small planets expand more due to weaker gravity; the effective runaway greenhouse threshold is about 35 W m(-2) higher for Mars, 10 W m(-2) higher for Earth or Venus, but only a few W m(-2) higher for a 10 Earth-mass planet. There is an underlying (expansion-neglected) trend of increasing runaway greenhouse threshold with planetary size (40 W m(-2) higher for a 10 Earth-mass planet than for Mars). Summing these opposing trends means that Venus-sized (or slightly smaller) planets are most susceptible to a runaway greenhouse. The habitable zone for pure water atmospheres is very narrow, with an insolation range of 0.07 times the solar constant. A wider habitable zone requires background gas and greenhouse gas: N2 and CO2 on Earth, which are biologically controlled. Thus, habitability depends on inhabitance.

  13. The effects of blue energy on future emissions of greenhouse gases and other atmospheric pollutants in China

    NARCIS (Netherlands)

    Gao, X.; Kroeze, C.

    2012-01-01

    Blue energy is the electricity generated from salinity gradients in rivers. About half of the global electricity demand could be satisfied if the technical potential was implemented. However, the technique is not yet implemented in full-scale operational plants. We estimate the potential effects of

  14. The Greenhouse Effect: Science and Policy.

    Science.gov (United States)

    Schneider, Stephen H.

    1989-01-01

    Discusses many of the scientific questions surrounding the greenhouse effect debate and the issue of plausible responses. Discussion includes topics concerning projecting emissions and greenhouse gas concentrations, estimating global climatic response, economic, social, and political impacts, and policy responses. (RT)

  15. The Greenhouse Effect and Built Environment Education.

    Science.gov (United States)

    Greenall Gough, Annette; Gough, Noel

    The greenhouse effect has always existed. Without the greenhouse effect, Earth could well have the oven-like environment of Venus or the deep-freeze environment of Mars. There is some debate about how much the Earth's surface temperature will rise given a certain amount of increase in the amount of greenhouse gases such as carbon dioxide, nitrous…

  16. 温室效应和温室气体监测%Greenhouse effect and greenhouse gases monitoring

    Institute of Scientific and Technical Information of China (English)

    韩香玉; 卢照方

    2011-01-01

    近年来,大气中温室气体含量的增加及其产生的温室效应,对气候和生态系统造成了一系列影响,因而对大气中温室气体含量的监测显得更为迫切.%Recently the increasing content of greenhouse gases in atmosphere and the greenhouse effect have created a series of influences on the climate and ecosystem, so it is urgent to minitor the content of greenhouse gases in atomosphere. This paper gives a general review of monitoring technologies for greenhouse gases.

  17. U.S. regional greenhouse gas emissions analysis comparing highly resolved vehicle miles traveled and CO2 emissions: mitigation implications and their effect on atmospheric measurements

    Science.gov (United States)

    Mendoza, D. L.; Gurney, K. R.

    2010-12-01

    Carbon dioxide (CO2) is the most abundant anthropogenic greenhouse gas and projections of fossil fuel energy demand show CO2 concentrations increasing indefinitely into the future. After electricity production, the transportation sector is the second largest CO2 emitting economic sector in the United States, accounting for 32.3% of the total U.S. emissions in 2002. Over 80% of the transport sector is composed of onroad emissions, with the remainder shared by the nonroad, aircraft, railroad, and commercial marine vessel transportation. In order to construct effective mitigation policy for the onroad transportation sector and more accurately predict CO2 emissions for use in transport models and atmospheric measurements, analysis must incorporate the three components that determine the CO2 onroad transport emissions: vehicle fleet composition, average speed of travel, and emissions regulation strategies. Studies to date, however, have either focused on one of these three components, have been only completed at the national scale, or have not explicitly represented CO2 emissions instead relying on the use of vehicle miles traveled (VMT) as an emissions proxy. National-level projections of VMT growth is not sufficient to highlight regional differences in CO2 emissions growth due to the heterogeneity of vehicle fleet and each state’s road network which determines the speed of travel of vehicles. We examine how an analysis based on direct CO2 emissions and an analysis based on VMT differ in terms of their emissions and mitigation implications highlighting potential biases introduced by the VMT-based approach. This analysis is performed at the US state level and results are disaggregated by road and vehicle classification. We utilize the results of the Vulcan fossil fuel CO2 emissions inventory which quantified emissions for the year 2002 across all economic sectors in the US at high resolution. We perform this comparison by fuel type,12 road types, and 12 vehicle types

  18. The terrestrial biosphere as a net source of greenhouse gases to the atmosphere.

    Science.gov (United States)

    Tian, Hanqin; Lu, Chaoqun; Ciais, Philippe; Michalak, Anna M; Canadell, Josep G; Saikawa, Eri; Huntzinger, Deborah N; Gurney, Kevin R; Sitch, Stephen; Zhang, Bowen; Yang, Jia; Bousquet, Philippe; Bruhwiler, Lori; Chen, Guangsheng; Dlugokencky, Edward; Friedlingstein, Pierre; Melillo, Jerry; Pan, Shufen; Poulter, Benjamin; Prinn, Ronald; Saunois, Marielle; Schwalm, Christopher R; Wofsy, Steven C

    2016-03-10

    The terrestrial biosphere can release or absorb the greenhouse gases, carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), and therefore has an important role in regulating atmospheric composition and climate. Anthropogenic activities such as land-use change, agriculture and waste management have altered terrestrial biogenic greenhouse gas fluxes, and the resulting increases in methane and nitrous oxide emissions in particular can contribute to climate change. The terrestrial biogenic fluxes of individual greenhouse gases have been studied extensively, but the net biogenic greenhouse gas balance resulting from anthropogenic activities and its effect on the climate system remains uncertain. Here we use bottom-up (inventory, statistical extrapolation of local flux measurements, and process-based modelling) and top-down (atmospheric inversions) approaches to quantify the global net biogenic greenhouse gas balance between 1981 and 2010 resulting from anthropogenic activities and its effect on the climate system. We find that the cumulative warming capacity of concurrent biogenic methane and nitrous oxide emissions is a factor of about two larger than the cooling effect resulting from the global land carbon dioxide uptake from 2001 to 2010. This results in a net positive cumulative impact of the three greenhouse gases on the planetary energy budget, with a best estimate (in petagrams of CO2 equivalent per year) of 3.9 ± 3.8 (top down) and 5.4 ± 4.8 (bottom up) based on the GWP100 metric (global warming potential on a 100-year time horizon). Our findings suggest that a reduction in agricultural methane and nitrous oxide emissions, particularly in Southern Asia, may help mitigate climate change.

  19. Remote sensing of atmospheric greenhouse gases: bridging spatial scales

    Science.gov (United States)

    Humpage, N.; Boesch, H.; Parker, R.; Hewson, W.; Sembhi, H.; Somkuti, P.; Webb, A.; Palmer, P. I.; Feng, L.

    2015-12-01

    Observed atmospheric variations of greenhouse gases (GHG) are determined by surface-atmosphere exchange, and atmospheric chemistry and transport. These processes occur over a wide spectrum of spatial and temporal scales. Confronting atmospheric transport models and ultimately improving the fidelity of surface flux estimates demands an integrated observing system that captures these scales. We will discuss using data the role of GHG remote sensing instruments and argue that our ability to deploy them from the ground and to fly them on satellite, aircraft, and unmanned airborne vehicles (UAV) mean that they represent the ideal technology to bridge the observed scales of variability. We will discuss a five-year record of global-scale column observations of CO2 and CH4 from the Japanese GOSAT satellite instrument that is available from University of Leicester as part of the ESA Climate Change Initiative. We will showcase new CO2 and CH4 column data that was collected by our shortwave infrared spectrometer GHOST oboard the NASA Global Hak during a regional survey over the eastern Pacific during early spring 2015, which included coincident overpasses from GOSAT and the NASA OCO-2. These data are being used to test atmospheric transport models over remote regions and to help validate satellite observations over the oceans. We will also discuss GHOST data collected on the UK Dornier 226 research aircraft to measure local-scale measurements over Leicester city centre, a major power plant, and downwind of a controlled Cumbrian heathland fire. Finally, we will report preliminary results from a new ground-based Fourier transform spectrometer station at Harwell (80 km west of London). We anticipate that this site will eventually join the TCCON network, which has been used to validation of satellite observations.

  20. The state of greenhouse gases in the atmosphere using global observations through 2014

    Science.gov (United States)

    Tarasova, Oksana; Koide, Hiroshi; Dlugokencky, Ed

    2016-04-01

    Oceanic and Atmospheric Administration (NOAA) Annual Greenhouse Gas Index shows that from 1990 to 2014 radiative forcing by long-lived greenhouse gases increased by 36%, with CO2 accounting for about 80% of this increase. The radiative forcing by all long-lived greenhouse gases in 2013 corresponded to a CO2-equivalent mole fraction of 481 ppm (http://www.esrl.noaa.gov/gmd/aggi). The Bulletin cover story explains the role of the water vapor in the greenhouse effect. In spite of water vapor being a strong greenhouse gas, it is the non-condensable greenhouse gases affected by human activities that serve as climate forcing agents; water vapor and clouds act as fast feedbacks. The strong water vapor feedback means that for a doubling of CO2 abundance from preindustrial conditions (from about 280 to 560 ppm), water vapor and clouds lead to a global increase in surface thermal energy that is about three times that of long-lived (non-condensable) greenhouse gases.

  1. A mental picture of the greenhouse effect - A pedagogic explanation

    Science.gov (United States)

    Benestad, Rasmus E.

    2016-01-01

    The popular picture of the greenhouse effect emphasises the radiation transfer but fails to explain the observed climate change. An old conceptual model for the greenhouse effect is revisited and presented as a useful resource in climate change communication. It is validated against state-of-the-art data, and nontraditional diagnostics show a physically consistent picture. The earth's climate is constrained by well-known and elementary physical principles, such as energy balance, flow, and conservation. Greenhouse gases affect the atmospheric optical depth for infrared radiation, and increased opacity implies higher altitude from which earth's equivalent bulk heat loss takes place. Such an increase is seen in the reanalyses, and the outgoing long-wave radiation has become more diffuse over time, consistent with an increased influence of greenhouse gases on the vertical energy flow from the surface to the top of the atmosphere. The reanalyses further imply increases in the overturning in the troposphere, consistent with a constant and continuous vertical energy flow. The increased overturning can explain a slowdown in the global warming, and the association between these aspects can be interpreted as an entanglement between the greenhouse effect and the hydrological cycle, where reduced energy transfer associated with increased opacity is compensated by tropospheric overturning activity.

  2. Atmospheric expansion in runaway greenhouse atmospheres: the inner edge of the habitable zone depends on planet mass

    Science.gov (United States)

    Goldblatt, C.; Zahnle, K. J.

    2014-12-01

    As a wet planet becomes hot, evaporation of the ocean provides a thick steam atmosphere. As the atmosphere thickens, the level at which optical depth is unity (whence radiative emission and absorption dominantly occur) rises into the atmosphere, first for thermal wavelengths and later for solar wavelengths. Consequently, two radiation limits emerge. First, an asymptotic limit on the thermal radiation, as the level at which thermal emission occurs tends towards a fixed temperature, decoupled from surface temperature. Next, a limit the albedo of the planet, as all incoming sunlight is either reflected or absorbed in the atmosphere and almost none reaches the surface. A runaway greenhouse occurs when the product of co-albedo and area-averaged incoming sunlight exceeds the thermal radiation limit. Earth today is perilously close to this [1].Returning to the first sentence, we generate a thick atmosphere: the height of optical depth of unity becomes a non-trivial fraction of the planetary radius. Hence the area of the absorbing and emitting surfaces increase. Thermal emission wins slightly, as this occurs higher, increasing thermal emission in all cases. The underlying tendency is for a larger thermal limit for heavier planets due to pressure effects, making these appear more resistant to a runaway. However, atmospheric expansion affects light planets more, making these seem much more resilient. The least resilient planet would be between Mars-size and Venus-size (Figure 1). It would be foolish to regard small planets as habitable. As the atmospheres become large, so does the problem of atmospheric escape. Theoretical considerations show hydrodynamic escape to happen disastrously for a Europa-size planet. The observation is that Mars is too feeble to hold on to any hefty atmosphere, even far from the Sun as it is, is probably relevant too. The take home points for habitable zone nerds are: (1) planet size matters (2) for small planets, atmospheric escape from a "moist

  3. The Greenhouse Effect in a Vial.

    Science.gov (United States)

    Golden, Richard; Sneider, Cary

    1989-01-01

    Presents an example of a greenhouse-effect experiment from the Climate Protection Institute. Analyzes the amount of carbon dioxide in ambient air, human exhalation, automobile exhaust, and nearly pure carbon dioxide by titrating with ammonia and bromthymol blue. (MVL)

  4. The detection of climate change due to the enhanced greenhouse effect

    Science.gov (United States)

    Schiffer, Robert A.; Unninayar, Sushel

    1991-01-01

    The greenhouse effect is accepted as an undisputed fact from both theoretical and observational considerations. In Earth's atmosphere, the primary greenhouse gas is water vapor. The specific concern today is that increasing concentrations of anthropogenically introduced greenhouse gases will, sooner or later, irreversibly alter the climate of Earth. Detecting climate change has been complicated by uncertainties in historical observations and measurements. Thus, the primary concern for the GEDEX project is how can climate change and enhanced greenhouse effects be unambiguously detected and quantified. Specifically examined are the areas of: Earth surface temperature; the free atmosphere (850 millibars and above); space-based measurements; measurement uncertainties; and modeling the observed temperature record.

  5. CO2 greenhouse in the early martian atmosphere: SO2 inhibits condensation.

    Science.gov (United States)

    Yung, Y L; Nair, H; Gerstell, M F

    1997-01-01

    Many investigators of the early martian climate have suggested that a dense carbon dioxide atmosphere was present and warmed the surface above the melting point of water (J.B. Pollack, J.F. Kasting, S.M. Richardson, and K. Poliakoff 1987. Icarus 71, 203-224). However, J.F. Kasting (1991. Icarus 94, 1-13) pointed out that previous thermal models of the primitive martian atmosphere had not considered the condensation of CO2. When this effect was incorporated, Kasting found that CO2 by itself is inadequate to warm the surface. SO2 absorbs strongly in the near UV region of the solar spectrum. While a small amount of SO2 may have a negligible effect by itself on the surface temperature, it may have significantly warmed the middle atmosphere of early Mars, much as ozone warms the terrestrial stratosphere today. If this region is kept warm enough to inhibit the condensation of CO2, then CO2 remains a viable greenhouse gas. Our preliminary radiative modeling shows that the addition of 0.1 ppmv of SO2 in a 2 bar CO2 atmosphere raises the temperature of the middle atmosphere by approximately 10 degrees, so that the upper atmosphere in a 1 D model remains above the condensation temperature of CO2. In addition, this amount of SO2 in the atmosphere provides an effective UV shield for a hypothetical biosphere on the martian surface.

  6. Climate and site management as driving factors for the atmospheric greenhouse gas exchange of a restored wetland

    DEFF Research Database (Denmark)

    Herbst, Mathias; Friborg, Thomas; Schelde, Kirsten;

    2013-01-01

    The atmospheric greenhouse gas (GHG) budget of a restored wetland in western Denmark was established for the years 2009–2011 from eddy covariance measurements of carbon dioxide (CO2) and methane (CH4) fluxes. The water table in the wetland, which was restored in 2002, was unregulated, and the veg......The atmospheric greenhouse gas (GHG) budget of a restored wetland in western Denmark was established for the years 2009–2011 from eddy covariance measurements of carbon dioxide (CO2) and methane (CH4) fluxes. The water table in the wetland, which was restored in 2002, was unregulated...... the atmosphere. However, in terms of the full annual GHG budget (assuming that 1 g CH4 is equivalent to 25 g CO2 with respect to the greenhouse effect over a time horizon of 100 years) the wetland was a sink in 2009, a source in 2010 and neutral in 2011. Complementary observations of meteorological factors...

  7. Hydrological controls on the tropospheric ozone greenhouse gas effect

    OpenAIRE

    Kuai, Le; Bowman, Kevin W.; Worden, Helen M.; Herman, Robert L.; Susan S. Kulawik

    2017-01-01

    The influence of the hydrological cycle in the greenhouse gas (GHG) effect of tropospheric ozone (O3) is quantified in terms of the O3longwave radiative effect (LWRE), which is defined as the net reduction of top-of-atmosphere flux due to total tropospheric O3absorption. The O3LWRE derived from the infrared spectral measurements by Aura’s Tropospheric Emission Spectrometer (TES) show that the spatiotemporal variation of LWRE is relevant to relative humidity, surface temperature, and troposphe...

  8. Biomarker Response to Galactic Cosmic Ray-Induced NOx and the Methane Greenhouse Effect in the Atmosphere of an Earthlike Planet Orbiting an M-Dwarf Star

    CERN Document Server

    Grenfell, J L; Patzer, B; Rauer, H; Segura, A; Stadelmann, A; Stracke, B; Titz, R; Von Paris, P; Grenfell, John Lee; Griessmeier, Jean-Mathias; Patzer, Beate; Rauer, Heike; Segura, Antigona; Stadelmann, Anja; Stracke, Barbara; Titz, Ruth; Paris, Philip von

    2007-01-01

    Planets orbiting in the habitable zone (HZ) of M-Dwarf stars are subject to high levels of galactic cosmic rays (GCRs) which produce nitrogen oxides in earthlike atmospheres. We investigate to what extent this NOx may modify biomarker compounds such as ozone (O3) and nitrous oxide (N2O), as well as related compounds such as water (H2O) (essential for life) and methane (CH4) (which has both abiotic and biotic sources) . Our model results suggest that such signals are robust, changing in the M-star world atmospheric column by up to 20% due to the GCR NOx effects compared to an M-star run without GCR effects and can therefore survive at least the effects of galactic cosmic rays. We have not however investigated stellar cosmic rays here. CH4 levels are about 10 times higher than on the Earth related to a lowering in hydroxyl (OH) in response to changes in UV. The increase is less than reported in previous studies. This difference arose partly because we used different biogenic input. For example, we employed 23% ...

  9. Climate and site management as driving factors for the atmospheric greenhouse gas exchange of a restored wetland

    DEFF Research Database (Denmark)

    Herbst, Mathias; Friborg, Thomas; Schelde, Kirsten;

    2012-01-01

    The full atmospheric greenhouse gas (GHG) budget of a restored wetland in Western Denmark could be established for the years 2009–2011 from eddy covariance measurements of carbon dioxide (CO2) and methane (CH4) fluxes. The water table in the wetland, being restored in 2002, was unregulated...... the atmosphere. However, in terms of the annual GHG budget (assuming that 1 g CH4 is equivalent to 25 g CO2 with respect to the greenhouse effect) the wetland was a sink in 2009, a source in 2010 and neutral in 2011. Complementary observations of meteorological factors and management activities were used...

  10. A Note on Fourier and the Greenhouse Effect

    CERN Document Server

    Postma, Joseph E

    2015-01-01

    Joseph Fourier's discovery of the greenhouse effect is discussed and is compared to the modern conception of the greenhouse effect. It is confirmed that what Fourier discovered is analogous to the modern concept of the greenhouse effect. However, the modern concept of the greenhouse effect is found to be based on a paradoxical analogy to Fourier's greenhouse work and so either Fourier's greenhouse work, the modern conception of the greenhouse effect, or the modern definition of heat is incorrect. The solution to this problem is not feigned to be given here.

  11. Fighting global warming by greenhouse gas removal: destroying atmospheric nitrous oxide thanks to synergies between two breakthrough technologies.

    Science.gov (United States)

    Ming, Tingzhen; de Richter, Renaud; Shen, Sheng; Caillol, Sylvain

    2016-04-01

    Even if humans stop discharging CO2 into the atmosphere, the average global temperature will still increase during this century. A lot of research has been devoted to prevent and reduce the amount of carbon dioxide (CO2) emissions in the atmosphere, in order to mitigate the effects of climate change. Carbon capture and sequestration (CCS) is one of the technologies that might help to limit emissions. In complement, direct CO2 removal from the atmosphere has been proposed after the emissions have occurred. But, the removal of all the excess anthropogenic atmospheric CO2 will not be enough, due to the fact that CO2 outgases from the ocean as its solubility is dependent of its atmospheric partial pressure. Bringing back the Earth average surface temperature to pre-industrial levels would require the removal of all previously emitted CO2. Thus, the atmospheric removal of other greenhouse gases is necessary. This article proposes a combination of disrupting techniques to transform nitrous oxide (N2O), the third most important greenhouse gas (GHG) in terms of current radiative forcing, which is harmful for the ozone layer and possesses quite high global warming potential. Although several scientific publications cite "greenhouse gas removal," to our knowledge, it is the first time innovative solutions are proposed to effectively remove N2O or other GHGs from the atmosphere other than CO2.

  12. Studying the Greenhouse Effect: A Simple Demonstration.

    Science.gov (United States)

    Papageorgiou, G.; Ouzounis, K.

    2000-01-01

    Studies the parameters involved in a presentation of the greenhouse effect and describes a simple demonstration of this effect. Required equipment includes a 100-120 watt lamp, a 250mL beaker, and a thermometer capable of recording 0-750 degrees Celsius together with a small amount of chloroform. (Author/SAH)

  13. The Runaway Greenhouse Effect on Earth and other Planets

    Science.gov (United States)

    Rabbette, Maura; Pilewskie, Peter; McKay, Christopher; Young, Robert

    2001-01-01

    Water vapor is an efficient absorber of outgoing longwave infrared radiation on Earth and is the primary greenhouse gas. Since evaporation increases with increasing sea surface temperature, and the increase in water vapor further increases greenhouse warming, there is a positive feedback. The runaway greenhouse effect occurs if this feedback continues unchecked until all the water has left the surface and enters the atmosphere. For Mars and the Earth the runaway greenhouse was halted when water vapor became saturated with respect to ice or liquid water respectively. However, Venus is considered to be an example of a planet where the runaway greenhouse effect did occur, and it has been speculated that if the solar luminosity were to increase above a certain limit, it would also occur on the Earth. Satellite data acquired during the Earth Radiation Budget Experiment (ERBE) under clear sky conditions shows that as the sea surface temperature (SST) increases, the rate of outgoing infrared radiation at the top of the atmosphere also increases, as expected. Over the pacific warm pool where the SST exceeds 300 K the outgoing radiation emitted to space actually decreases with increasing SST, leading to a potentially unstable system. This behavior is a signature of the runaway greenhouse effect on Earth. However, the SST never exceeds 303K, thus the system has a natural cap which stops the runaway. According to Stefan-Boltzmann's law the amount of heat energy radiated by the Earth's surface is proportional to (T(sup 4)). However, if the planet has a substantial atmosphere, it can absorb all infrared radiation from the lower surface before the radiation penetrates into outer space. Thus, an instrument in space looking at the planet does not detect radiation from the surface. The radiation it sees comes from some level higher up. For the earth#s atmosphere the effective temperature (T(sub e)) has a value of 255 K corresponding to the middle troposphere, above most of the

  14. Assessing Greenhouse Gas emissions in the Greater Toronto Area using atmospheric observations (Invited)

    Science.gov (United States)

    Vogel, F. R.; Chan, E.; Huang, L.; Levin, I.; Worthy, D.

    2013-12-01

    Urban areas are said to be responsible for approximately 75% of anthropogenic Greenhouse Gases (GHGs) emissions while comprising only two percent of the land area [1]. This limited spatial expansion should facilitate a monitoring of anthropogenic GHGs from atmospheric observations. As major sources of emissions, cities also have a huge potential to drive emissions reductions. To effectively manage emissions, cities must however, first measure and report these publicly [2]. Modelling studies and measurements of CO2 from fossil fuel burning (FFCO2) in densely populated areas does, however, pose several challenges: Besides continuous in-situ observations, i.e. finding an adequate atmospheric transport model, a sufficiently fine-grained FFCO2 emission model and the proper background reference observations to distinguish the large-scale from the local/urban contributions to the observed FFCO2 concentration offsets ( ΔFFCO2) are required. Pilot studies which include the data from two 'sister sites*' in the vicinity of Toronto, Canada helped to derive flux estimates for Non-CO2 GHGs [3] and improve our understanding of urban FFCO2 emissions. Our 13CO2 observations reveal that the contribution of natural gas burning (mostly due to domestic heating) account for 80%×7% of FFCO2 emissions in the Greater Toronto Area (GTA) during winter. Our 14CO2 observations in the GTA, furthermore, show that the local offset of CO2 (ΔCO2) between our two sister sites can be largely attributed to urban FFCO2 emissions. The seasonal cycle of the observed ΔFFCO2 in Toronto, combined with high-resolution atmospheric modeling, helps to independently assess the contribution from different emission sectors (transportation, primary energy and industry, domestic heating) as predicted by a dedicated city-scale emission inventory, which deviates from a UNFCCC-based inventory. [1] D. Dodman. 2009. Blaming cities for climate change? An analysis of urban greenhouse gas emissions inventories

  15. Revisiting the scattering greenhouse effect of CO2 ice clouds

    CERN Document Server

    Kitzmann, Daniel

    2016-01-01

    Carbon dioxide ice clouds are thought to play an important role for cold terrestrial planets with thick CO2 dominated atmospheres. Various previous studies showed that a scattering greenhouse effect by carbon dioxide ice clouds could result in a massive warming of the planetary surface. However, all of these studies only employed simplified two-stream radiative transfer schemes to describe the anisotropic scattering. Using accurate radiative transfer models with a general discrete ordinate method, this study revisits this important effect and shows that the positive climatic impact of carbon dioxide clouds was strongly overestimated in the past. The revised scattering greenhouse effect can have important implications for the early Mars, but also for planets like the early Earth or the position of the outer boundary of the habitable zone.

  16. Greenhouse

    Data.gov (United States)

    Federal Laboratory Consortium — PurposeThe greenhouse at ERDC’s Cold Regions Research and Engineering Laboratory (CRREL) is used for germination and root-growth studies to support basic and field...

  17. The runaway greenhouse: implications for future climate change, geoengineering and planetary atmospheres.

    Science.gov (United States)

    Goldblatt, Colin; Watson, Andrew J

    2012-09-13

    The ultimate climate emergency is a 'runaway greenhouse': a hot and water-vapour-rich atmosphere limits the emission of thermal radiation to space, causing runaway warming. Warming ceases only after the surface reaches approximately 1400 K and emits radiation in the near-infrared, where water is not a good greenhouse gas. This would evaporate the entire ocean and exterminate all planetary life. Venus experienced a runaway greenhouse in the past, and we expect that the Earth will in around 2 billion years as solar luminosity increases. But could we bring on such a catastrophe prematurely, by our current climate-altering activities? Here, we review what is known about the runaway greenhouse to answer this question, describing the various limits on outgoing radiation and how climate will evolve between these. The good news is that almost all lines of evidence lead us to believe that is unlikely to be possible, even in principle, to trigger full a runaway greenhouse by addition of non-condensible greenhouse gases such as carbon dioxide to the atmosphere. However, our understanding of the dynamics, thermodynamics, radiative transfer and cloud physics of hot and steamy atmospheres is weak. We cannot therefore completely rule out the possibility that human actions might cause a transition, if not to full runaway, then at least to a much warmer climate state than the present one. High climate sensitivity might provide a warning. If we, or more likely our remote descendants, are threatened with a runaway greenhouse, then geoengineering to reflect sunlight might be life's only hope. Injecting reflective aerosols into the stratosphere would be too short-lived, and even sunshades in space might require excessive maintenance. In the distant future, modifying Earth's orbit might provide a sustainable solution. The runaway greenhouse also remains relevant in planetary sciences and astrobiology: as extrasolar planets smaller and nearer to their stars are detected, some will be in

  18. Physics of greenhouse effect and convection in warm oceans

    Science.gov (United States)

    Inamdar, A. K.; Ramanathan, V.

    1994-01-01

    Sea surface temperature (SST) in roughly 50% of the tropical Pacific Ocean is warm enough (SST greater than 300 K) to permit deep convection. This paper examines the effects of deep convection on the climatological mean vertical distributions of water vapor and its greenhouse effect over such warm oceans. The study, which uses a combination of satellite radiation budget observations, atmospheric soundings deployed from ships, and radiation model calculations, also examines the link between SST, vertical distribution of water vapor, and its greenhouse effect in the tropical oceans. Since the focus of the study is on the radiative effects of water vapor, the radiation model calculations do not include the effects of clouds. The data are grouped into nonconvective and convective categories using SST as an index for convective activity. On average, convective regions are more humid, trap significantly more longwave radiation, and emit more radiation to the sea surface. The greenhouse effect in regions of convection operates as per classical ideas, that is, as the SST increases, the atmosphere traps the excess longwave energy emitted by the surface and reradiates it locally back to the ocean surface. The important departure from the classical picture is that the net (up minus down) fluxes at the surface and at the top of the atmosphere decrease with an increase in SST; that is, the surface and the surface-troposphere column lose the ability to radiate the excess energy to space. The cause of this super greenhouse effect at the surface is the rapid increase in the lower-troposphere humidity with SST; that of the column is due to a combination of increase in humidity in the entire column and increase in the lapse rate within the lower troposphere. The increase in the vertical distribution of humidity far exceeds that which can be attributed to the temperature dependence of saturation vapor pressure; that is, the tropospheric relative humidity is larger in convective

  19. Future atmospheric conditions increase the greenhouse gas intensity of rice production

    Science.gov (United States)

    Van Groenigen, K.; Van Kessel, C.; Hungate, B. A.

    2012-12-01

    Elevated levels of atmospheric CO2 and rising temperatures are both expected to alter rice yields and greenhouse gas (GHG) emissions from rice paddies. This is important, because rice cultivation is one of the largest anthropogenic sources of the potent GHG methane (CH4) and rice is the world's second-most produced staple crop. Because global food demand is growing, it makes sense to assess GHG emissions from croplands on the basis of yield rather than land area, so that efforts to reduce GHG emissions occur with taking into consideration the effects on food production. However, it is unclear whether or how the GHG intensity (that is, yield-scaled GHG emissions) of cropping systems will be affected by future atmospheric conditions. Using meta-analysis, we show that elevated atmospheric CO2 (ranging from 550 to 743 ppmV) and warming (ranging from +0.8°C to +6°C) both increase the GHG intensity of rice cultivation. Elevated atmospheric CO2 increased GHG intensity by 31.4%, because CH4 emissions are stimulated more than rice yields. Warming increased GHG intensity by 11.8% per 1°C, largely due to a decrease in yield. Our findings underscore the need for mitigation and adaptation efforts to secure global food supply while at the same time keeping GHG emissions in check.

  20. A Simple Experiment to Demonstrate the Effects of Greenhouse Gases

    Science.gov (United States)

    Keating, C. F.

    2007-01-01

    The role of greenhouse gases in our atmosphere is the subject of considerable discussion and debate. Global warming is well-documented, as is the continually increasing amount of greenhouse gases that human activity puts in the air. Is there a relationship between the two? The simple experiment described in this paper provides a good demonstration…

  1. Greenhouse effect simulator - An educational application

    Science.gov (United States)

    Machado, Alan Freitas; Viveiros, Bruno Martins; da Silva, Claudio Elias

    2016-12-01

    Using the program "Modellus", we intend to create a simple simulation to show the impacts that the Greenhouse Effect might have, in a didactic and friendly way, in order to expose this notions to high and middle school students. In order to do so, we created a program that will simulate a sweep, through the Troposphere, and create two lines in a graphic, one showing the temperatures behavior, in normal conditions, and the other showing how the temperature behaves in the presence of excess of Greenhouse gases. The main purpose of the project is to use the model in schools and try to make kids more conscious of their roles in our so society, showing them the consequences of the tendency of our acts, stimulating them to be more proactives to change the future.

  2. Continuous measurements of greenhouse gases and atmospheric oxygen at the Namib Desert Atmospheric Observatory

    Science.gov (United States)

    Morgan, E. J.; Lavrič, J. V.; Seifert, T.; Chicoine, T.; Day, A.; Gomez, J.; Logan, R.; Sack, J.; Shuuya, T.; Uushona, E. G.; Vincent, K.; Schultz, U.; Brunke, E.-G.; Labuschagne, C.; Thompson, R. L.; Schmidt, S.; Manning, A. C.; Heimann, M.

    2015-02-01

    A new coastal background site has been established for observations of greenhouse gases (GHGs) in the central Namib Desert at Gobabeb, Namibia. The location of the site was chosen to provide observations for a data-poor region in the global sampling network for GHGs. Semi-automated, continuous measurements of carbon dioxide, methane, nitrous oxide, carbon monoxide, atmospheric oxygen, and basic meteorology are made at a height of 21 m a.g.l., 50 km from the coast at the northern border of the Namib Sand Sea. Atmospheric oxygen is measured with a differential fuel cell analyzer (DFCA). Carbon dioxide and methane are measured with an early-model cavity ring-down spectrometer (CRDS); nitrous oxide and carbon monoxide are measured with an off-axis integrated cavity output spectrometer (OA-ICOS). Instrument-specific water corrections are employed for both the CRDS and OA-ICOS instruments in lieu of drying. The performance and measurement uncertainties are discussed in detail. As the station is located in a remote desert environment, there are some particular challenges, namely fine dust, high diurnal temperature variability, and minimal infrastructure. The gas handling system and calibration scheme were tailored to best fit the conditions of the site. The CRDS and DFCA provide data of acceptable quality when base requirements for operation are met, specifically adequate temperature control in the laboratory and regular supply of electricity. In the case of the OA-ICOS instrument, performance is significantly improved through the implementation of a drift correction through frequent measurements of a working tank.

  3. New Evidence of an Enhanced Greenhouse Effect

    CERN Document Server

    Benestad, Rasmus E

    2011-01-01

    The state of earth's climate is constrained by well-known physical principles such as energy balance and the conservation of energy. Increased greenhouse gas concentrations affect the atmospheric optical depth, and physical consistency implies that changes in the energy transfer in terms of infra-red light must be compensated by other means of energy flow. Here, a simple heuristic and comprehensive model is used to interpret new aspects of real-world data. It is shown that trends in tropospheric overturning activity and the estimated altitude where earth's bulk heat loss should place are two independent indicators of climate change. There has been increased vertical overturning in the middle and upper parts of the troposphere since 1995 on a global scale. Greater overturning compensates for reduced radiative energy transfer associated with increased optical depth. An increased optical depth is also expected to raise the altitude from where planetary bulk heat loss takes place according to the heuristic model,...

  4. Comment on "Cosmic-ray-driven reaction and greenhouse effect of halogenated molecules: Culprits for atmospheric ozone depletion and global climate change"

    Science.gov (United States)

    Müller, Rolf; Grooß, Jens-Uwe

    2014-04-01

    Lu's "cosmic-ray-driven electron-induced reaction (CRE) theory" is based on the assumption that the CRE reaction of halogenated molecules (e.g., chlorofluorocarbons (CFCs), HCl, ClONO2) adsorbed or trapped in polar stratospheric clouds in the winter polar stratosphere is the key step in forming photoactive halogen species that are the cause of the springtime ozone hole. This theory has been extended to a warming theory of halogenated molecules for climate change. In this comment, we discuss the chemical and physical foundations of these theories and the conclusions derived from the theories. First, it is unclear whether the loss rates of halogenated molecules induced by dissociative electron attachment (DEA) observed in the laboratory can also be interpreted as atmospheric loss rates, but even if this were the case, the impact of DEA-induced reactions on polar chlorine activation and ozone loss in the stratosphere is limited. Second, we falsify several conclusions that are reported on the basis of the CRE theory: There is no polar ozone loss in darkness, there is no apparent 11-year periodicity in polar total ozone measurements, the age of air in the polar lower stratosphere is much older than 1-2 years, and the reported detection of a pronounced recovery (by about 20-25%) in Antarctic total ozone measurements by the year 2010 is in error. There are also conclusions about the future development of sea ice and global sea level which are fundamentally flawed because Archimedes' principle is neglected. Many elements of the CRE theory are based solely on correlations between certain datasets which are no substitute for providing physical and chemical mechanisms causing a particular behavior noticeable in observations. In summary, the CRE theory cannot be considered as an independent, alternative mechanism for polar stratospheric ozone loss and the conclusions on recent and future surface temperature and global sea level change do not have a physical basis.

  5. HFCs contribution to the greenhouse effect. Present and projected estimations

    Energy Technology Data Exchange (ETDEWEB)

    Libre, J.M.; Elf-Atochem, S.A. [Central Research & Development, Paris (France)

    1997-12-31

    This paper reviews data that can be used to calculate hydrofluorocarbon (HFC) contribution to the greenhouse effect and compare it to other trace gas contributions. Projections are made for 2010 and 2100 on the basis of available emission scenarios. Industrial judgement on the likelihood of those scenarios is also developed. Calculations can be made in two different ways: from Global Warming Potential weighted emissions of species or by direct calculation of radiative forcing based on measured and projected atmospheric concentrations of compounds. Results show that HFCs corresponding to commercial uses have a negligible contribution to the greenhouse effect in comparison with other trace gases. The projected contributions are also very small even if very high emission scenarios are maintained for decades. In 2010 this contribution remains below 1%. Longer term emissions projections are difficult. However, based on the IPCC scenario IS92a, in spite of huge emissions projected for the year 2100, the HFC contribution remains below 3%. Actually many factors indicate that the real UFC contribution to the greenhouse effect will be even smaller than presented here. Low emissive systems and small charges will likely improve sharply in the future and have drastically improved in the recent past. HFC technology implementation is likely to grow in the future, reach a maximum before the middle of the next century; the market will stabilise driven by recycling, closing of systems and competitive technologies. This hypothesis is supported by previous analysis of the demand for HTCs type applications which can be represented by {open_quotes}S{close_quotes} type curves and by recent analysis indicating that the level of substitution of old products by HFCs is growing slowly. On the basis of those data and best industrial judgement, the contribution of HFCs to the greenhouse effect is highly likely to remain below 1% during the next century. 11 refs., 2 figs., 5 tabs.

  6. ObsPack: a framework for the preparation, delivery, and attribution of atmospheric greenhouse gas data

    NARCIS (Netherlands)

    Masarie, K. A.; Peters, W.; Jacobson, A. R.; Tans, P. P.

    2014-01-01

    Observation Package (ObsPack) is a framework designed to bring together atmospheric greenhouse gas observations from a variety of sampling platforms, prepare them with specific applications in mind, and package and distribute them in a self-consistent and well-documented product. Data products creat

  7. ObsPack: a framework for the preparation, delivery, and attribution of atmospheric greenhouse gas measurements

    NARCIS (Netherlands)

    Masarie, K. A.; Peters, W.; Jacobson, A. R.; Tans, P. P.

    2014-01-01

    Observation Package (ObsPack) is a framework designed to bring together atmospheric greenhouse gas observations from a variety of sampling platforms, prepare them with specific applications in mind, and package and distribute them in a self-consistent and well-documented product. Data products creat

  8. Hydrogen-nitrogen greenhouse warming in Earth's early atmosphere.

    Science.gov (United States)

    Wordsworth, Robin; Pierrehumbert, Raymond

    2013-01-04

    Understanding how Earth has sustained surface liquid water throughout its history remains a key challenge, given that the Sun's luminosity was much lower in the past. Here we show that with an atmospheric composition consistent with the most recent constraints, the early Earth would have been significantly warmed by H(2)-N(2) collision-induced absorption. With two to three times the present-day atmospheric mass of N(2) and a H(2) mixing ratio of 0.1, H(2)-N(2) warming would be sufficient to raise global mean surface temperatures above 0°C under 75% of present-day solar flux, with CO(2) levels only 2 to 25 times the present-day values. Depending on their time of emergence and diversification, early methanogens may have caused global cooling via the conversion of H(2) and CO(2) to CH(4), with potentially observable consequences in the geological record.

  9. Testing Plant Responses to Rarified Atmospheres for Inflatable Greenhouses

    Science.gov (United States)

    Corey, Kenneth A.

    2000-01-01

    Reduced atmospheric pressures will likely be used to minimize mass and engineering requirements for plant growth habitats used in extraterrestrial applications. A chamber with high vacuum capability was used to design and begin construction of a system for testing plant responses to reduced pressure atmospheres. Several preliminary tests were conducted to evaluate chamber suitability for plant tests and to determine performance of thermal and vacuum systems at ambient and reduced pressure atmospheres down to 0.1 atm. The first tests consisted of measurements of internal gas volume and leakage rate. The method for volume determination was quite sensitive and will be needed for plant gas exchange measurements and calculations. This information will also be used in conjunction with the leak rate. Measured leak rates on the order of 0.46 mm Hg/min at 76 mm Hg pressure are low enough to conduct sensitive carbon dioxide exchange rate measurements at reduced pressure given an adequate plant sample (0.5 to 1.0 sq m area). A test rack with lighting provided by three high-pressure sodium vapor lamps was built to accommodate both short-term and long-term plant responses. Initial short-term experiments with lettuce showed that a pressure of 77 mm Hg resulted in a 6.1-fold increase in the rate of water loss compared to water loss at ambient pressure. Plants were severely wilted after 30 minutes exposure to 77 mm Hg. Water loss was found to be inversely correlated with atmospheric pressure over the range of pressures from 0.2 to 1.0 atm; the rate of water loss at 0.2 atm was 4.3 times higher than water loss at ambient pressure. Older leaves showed moderate wilting during exposure to 156 mm Hg, but those exposed to 345 mm, Hg remained turgid. Results suggest a reduced atmospheric pressure limit of 0.2 to 0.3 atm for lettuce grown in a solid medium. Follow-up experiments with carbon dioxide control and control at high relative humidity (> 90 %) will be needed to further confirm

  10. On the role of atmosphere-ocean interactions in the expected long-term changes of the Earth's ozone layer caused by greenhouse gases

    Science.gov (United States)

    Zadorozhny, Alexander; Dyominov, Igor

    It is well known that anthropogenic emissions of greenhouse gases into the atmosphere produce a global warming of the troposphere and a global cooling of the stratosphere. The expected stratospheric cooling essentially influences the ozone layer via increased polar stratospheric cloud formation and via temperature dependences of the gas phase reaction rates. One more mechanism of how greenhouse gases influences the ozone layer is enhanced water evaporation from the oceans into the atmosphere because of increasing temperatures of the ocean surface due to greenhouse effect. The subject of this paper is a study of the influence of anthropogenic pollution of the atmosphere by the greenhouse gases CO2, CH4, N2O and ozone-depleting chlorine and bromine compounds on the expected long-term changes of the ozone layer with taking into account an increase of water vapour content in the atmosphere due to greenhouse effect. The study based on 2-D zonally averaged interactive dynamical radiative-photochemical model of the troposphere and stratosphere. The model allows to self-consistently calculating diabatic circulation, temperature, gaseous composition of the troposphere and stratosphere at latitudes from the South to North Poles, as well as distribution of sulphate aerosol particles and polar stratospheric clouds of two types. It was supposed in the model that an increase of the ocean surface temperature caused by greenhouse effect is similar to calculated increase of atmospheric surface temperature. Evaporation rate from the ocean surface was computed in dependence of latitude. The model time-dependent runs were made for the period from 1975 to 2100 using two IPCC scenarios depicting maximum and average expected increases of greenhouse gases in the atmosphere. The model calculations show that anthropogenic increasing of water vapour abundance in the atmosphere due to heating of the ocean surface caused by greenhouse effect gives a sensible contribution to the expected ozone

  11. The Runaway Greenhouse: implications for future climate change, geoengineering and planetary atmospheres

    CERN Document Server

    Goldblatt, Colin

    2012-01-01

    The ultimate climate emergency is a "runaway greenhouse": a hot and water vapour rich atmosphere limits the emission of thermal radiation to space, causing runaway warming. Warming ceases only once the surface reaches ~1400K and emits radiation in the near-infrared, where water is not a good greenhouse gas. This would evaporate the entire ocean and exterminate all planetary life. Venus experienced a runaway greenhouse in the past, and we expect that Earth will in around 2 billion years as solar luminosity increases. But could we bring on such a catastrophe prematurely, by our current climate-altering activities? Here we review what is known about the runaway greenhouse to answer this question, describing the various limits on outgoing radiation and how climate will evolve between these. The good news is that almost all lines of evidence lead us to believe that is unlikely to be possible, even in principle, to trigger full a runaway greenhouse by addition of non-condensible greenhouse gases such as carbon diox...

  12. Climate and greenhouse effect gas: glaciated archives data. Climat et gaz a effet de serre: les donnees des archives glaciaires

    Energy Technology Data Exchange (ETDEWEB)

    Lorius, C. (Laboratoire de Glaciologie et Geophysique de l' Environnement, 38 - Saint-Martin-d' Heres (FR))

    1991-01-01

    Ice caps in Antarctica or Greenland have recorded the anthropogenic effect on atmospheric composition and especially on greenhouse effect gases such as carbon dioxide and methane. 2000 meter depth drilling samples allowed to study the climates for 150 000 years ago; hot and cold climates are ruled by periodic movement of the Earth around the sun and by more or less elevated concentration of greenhouse effect gases in the atmosphere. Prospects for to morrow climates and anthropogenic contribution are then possible.

  13. European emissions of halogenated greenhouse gases inferred from atmospheric measurements.

    Science.gov (United States)

    Keller, Christoph A; Hill, Matthias; Vollmer, Martin K; Henne, Stephan; Brunner, Dominik; Reimann, Stefan; O'Doherty, Simon; Arduini, Jgor; Maione, Michela; Ferenczi, Zita; Haszpra, Laszlo; Manning, Alistair J; Peter, Thomas

    2012-01-01

    European emissions of nine representative halocarbons (CFC-11, CFC-12, Halon 1211, HCFC-141b, HCFC-142b, HCFC-22, HFC-125, HFC-134a, HFC-152a) are derived for the year 2009 by combining long-term observations in Switzerland, Italy, and Ireland with campaign measurements from Hungary. For the first time, halocarbon emissions over Eastern Europe are assessed by top-down methods, and these results are compared to Western European emissions. The employed inversion method builds on least-squares optimization linking atmospheric observations with calculations from the Lagrangian particle dispersion model FLEXPART. The aggregated halocarbon emissions over the study area are estimated at 125 (106-150) Tg of CO(2) equiv/y, of which the hydrofluorocarbons (HFCs) make up the most important fraction with 41% (31-52%). We find that chlorofluorocarbon (CFC) emissions from banks are still significant and account for 35% (27-43%) of total halocarbon emissions in Europe. The regional differences in per capita emissions are only small for the HFCs, while emissions of CFCs and hydrochlorofluorocarbons (HCFCs) tend to be higher in Western Europe compared to Eastern Europe. In total, the inferred per capita emissions are similar to estimates for China, but 3.5 (2.3-4.5) times lower than for the United States. Our study demonstrates the large benefits of adding a strategically well placed measurement site to the existing European observation network of halocarbons, as it extends the coverage of the inversion domain toward Eastern Europe and helps to better constrain the emissions over Central Europe.

  14. Greenhouse effect of chlorofluorocarbons and other trace gases

    Science.gov (United States)

    Hansen, James; Lacis, Andrew; Prather, Michael

    1989-01-01

    A comparison is made of the radiative (greenhouse) forcing of the climate system due to changes of atmospheric chlorofluorocarbons and other trace gases. It is found that CFCs, defined to include chlorofluorocarbons, chlorocarbons, and fluorocarbons, now provide about one-quater of current annual increases in anthropogenic greenhouse climate forcing. If the growth rates of CFC production in the early 1970s had continued to the present, current annual growth of climate forcing due to CFCs would exceed that due to CO2.

  15. The impacts of recent permafrost thaw on land-atmosphere greenhouse gas exchange

    Science.gov (United States)

    Hayes, Daniel J.; Kicklighter, David W.; McGuire, Anthony; Chen, Min; Zhuang, Qianlai; Yuan, Fengming; Melillo, Jerry M.; Wullschleger, Stan D.

    2014-01-01

    Permafrost thaw and the subsequent mobilization of carbon (C) stored in previously frozen soil organic matter (SOM) have the potential to be a strong positive feedback to climate. As the northern permafrost region experiences as much as a doubling of the rate of warming as the rest of the Earth, the vast amount of C in permafrost soils is vulnerable to thaw, decomposition and release as atmospheric greenhouse gases. Diagnostic and predictive estimates of high-latitude terrestrial C fluxes vary widely among different models depending on how dynamics in permafrost, and the seasonally thawed 'active layer' above it, are represented. Here, we employ a process-based model simulation experiment to assess the net effect of active layer dynamics on this 'permafrost carbon feedback' in recent decades, from 1970 to 2006, over the circumpolar domain of continuous and discontinuous permafrost. Over this time period, the model estimates a mean increase of 6.8 cm in active layer thickness across the domain, which exposes a total of 11.6 Pg C of thawed SOM to decomposition. According to our simulation experiment, mobilization of this previously frozen C results in an estimated cumulative net source of 3.7 Pg C to the atmosphere since 1970 directly tied to active layer dynamics. Enhanced decomposition from the newly exposed SOM accounts for the release of both CO2 (4.0 Pg C) and CH4 (0.03 Pg C), but is partially compensated by CO2 uptake (0.3 Pg C) associated with enhanced net primary production of vegetation. This estimated net C transfer to the atmosphere from permafrost thaw represents a significant factor in the overall ecosystem carbon budget of the Pan-Arctic, and a non-trivial additional contribution on top of the combined fossil fuel emissions from the eight Arctic nations over this time period.

  16. Greenhouse effect and its impact on Africa

    Energy Technology Data Exchange (ETDEWEB)

    Suliman, M. (ed.)

    1990-01-01

    Changes that may occur in Africa as a result of global warming are outlined. They include changes to agriculture, water resources, and in sea level and as a result of CO{sub 2} fertilization. The global problem is outlined, and solutions are considered such as the use of non-carbon fuels and increasing carbon sinks. The economic implications for third world countries, of global warming are discussed, together with policy responses. Agro-forestry is suggested as a way to reduce CO{sub 2} emissions. The problem of food insecurity is mentioned and the Sudan is taken as an example. The report ends with recommendations to limit the greenhouse effect and reduce the impact it could have on Africa. 17 refs., 14 figs., 4 tabs.

  17. The greenhouse effect; L'effet de serre

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-07-01

    Simulations used by the climatologists forecast an increase of the world average temperature of 2 degrees between 1990 and 2100, resulting from the greenhouse effect gases. This paper gives examples of consequences of this climatic warming and presents the international agreements to fight against the greenhouse effect gases decided at Rio, Kyoto and, Buenos Aires. (A.L.B.)

  18. Ideas of Elementary Students about Reducing the "Greenhouse Effect."

    Science.gov (United States)

    Francis, Claire; And Others

    1993-01-01

    Presents the results of a questionnaire given to 563 elementary students to study their ideas of actions that would reduce the greenhouse effect. Most of the children (87%) appreciated that planting trees would help reduce global warming. During interviews it was discovered that children were confused between the greenhouse effect and ozone layer…

  19. The greenhouse effect; L'effet de serre

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    In the framework of the sustainable development, this paper presents the greenhouse effect and its impact on the climatic change, the world interest from Rio to Buenos Aires, the human activities producing the carbon dioxide and responsible of the greenhouse effect, the carbon dioxide emission decrease possibilities and shows the necessity of the electric power producers contribution. (A.L.B.)

  20. STRATOSPHERIC TEMPERATURES AND WATER LOSS FROM MOIST GREENHOUSE ATMOSPHERES OF EARTH-LIKE PLANETS

    Energy Technology Data Exchange (ETDEWEB)

    Kasting, James F.; Kopparapu, Ravi K. [Department of Geosciences, The Pennsylvania State University, State College, PA 16801 (United States); Chen, Howard, E-mail: jfk4@psu.edu, E-mail: hwchen@bu.edu [Department of Astronomy, Boston University, 725 Commonwealth Ave., Boston, MA 02215 (United States)

    2015-11-01

    A radiative-convective climate model is used to calculate stratospheric temperatures and water vapor concentrations for ozone-free atmospheres warmer than that of modern Earth. Cold, dry stratospheres are predicted at low surface temperatures, in agreement with recent 3D calculations. However, at surface temperatures above 350 K, the stratosphere warms and water vapor becomes a major upper atmospheric constituent, allowing water to be lost by photodissociation and hydrogen escape. Hence, a moist greenhouse explanation for loss of water from Venus, or some exoplanet receiving a comparable amount of stellar radiation, remains a viable hypothesis. Temperatures in the upper parts of such atmospheres are well below those estimated for a gray atmosphere, and this factor should be taken into account when performing inverse climate calculations to determine habitable zone boundaries using 1D models.

  1. Stratospheric Temperatures and Water Loss from Moist Greenhouse Atmospheres of Earth-like Planets

    CERN Document Server

    Kasting, James F; Kopparapu, Ravi Kumar

    2015-01-01

    A radiative-convective climate model is used to calculate stratospheric temperatures and water vapor concentrations for ozone-free atmospheres warmer than that of modern Earth. Cold, dry stratospheres are predicted at low surface temperatures, in agreement with recent 3-D calculations. However, at surface temperatures above 350 K, the stratosphere warms and water vapor becomes a major upper atmospheric constituent, allowing water to be lost by photodissociation and hydrogen escape. Hence, a 'moist greenhouse' explanation for loss of water from Venus, or some exoplanet receiving a comparable amount of stellar radiation, remains a viable hypothesis. Temperatures in the upper parts of such atmospheres are well below those estimated for a gray atmosphere, and this factor should be taken into account when performing 'inverse' climate calculations to determine habitable zone boundaries using 1-D models.

  2. Time-Dependent Calculations of an Impulsive Impact-Triggered Runaway Greenhouse Atmosphere on Mars

    Science.gov (United States)

    Segura, T. L.; Toon, O. B.; McKay, C. P.

    2003-05-01

    The existence of a few dozen craters of size 200 km and greater proves that large (30-250 km diameter) impacts were abundant in the early history of Mars. Injected water from three sources (the impactor itself, water innate to the crater, and from melting of the polar caps) provide periods of rain following such impacts. Very hot (> 1600 K), global debris blankets are another consequence of these large impacts, and these layers create a thermal pulse that propagates into the subsurface, melting additional water. Both the melted and precipitated water and debris blanket combine to produce a temporarily altered climate on the planet. This research provides the first time-dependent modeled calcuations of this altered climate, and focuses in particular on a possible "runaway" greenhouse state that might be initiated as a result of the additional heat and a sufficiently rapid supply of the melted and precipitated water to the atmosphere. Our model is a 1-D radiative-convective model coupled to a 1-D model of the regolith to calculate the evolution of the surface and subsurface temperatures. The effects of latent heating, cloud condensation, precipitation, and evaporation are included in the model.

  3. Reply to "Comment on 'Falsification Of The Atmospheric CO2 Greenhouse Effects Within The Frame Of Physics' by Joshua B. Halpern, Christopher M. Colose, Chris Ho-Stuart, Joel D. Shore, Arthur P. Smith, J\\"org Zimmermann"

    OpenAIRE

    Gerlich, Gerhard; Tscheuschner, Ralf D.

    2010-01-01

    It is shown that the notorious claim by Halpern et al. recently repeated in their comment that the method, logic, and conclusions of our "Falsification Of The CO2 Greenhouse Effects Within The Frame Of Physics" would be in error has no foundation. Since Halpern et al. communicate our arguments incorrectly, their comment is scientifcally vacuous. In particular, it is not true that we are "trying to apply the Clausius statement of the Second Law of Thermodynamics to only one side of a heat tran...

  4. Effect of greenhouse gas emissions on stratospheric ozone depletion

    NARCIS (Netherlands)

    Velders GJM; LLO

    1997-01-01

    The depletion of the ozone layer is caused mainly by the increase in emissions of chlorine- and bromine-containing compounds like CFCs, halons, carbon tetrachloride, methyl chloroform and methyl bromide. Emissions of greenhouse gases can affect the depletion of the ozone layer through atmospheric i

  5. Climate - Greenhouse effect - Energy; Klima - drivhuseffekt - energi

    Energy Technology Data Exchange (ETDEWEB)

    Henriksen, Thormod; Kanestroem, Ingolf

    2001-07-01

    This book explains what is understood by climate systems and the concept of greenhouse effect. It also gives a survey of the world's energy consumption, energy reserves and renewable energy sources. Today, 75 - 80 per cent of the world's energy consumption involves fossil fuel. These are the sources that cause the CO{sub 2} emissions. What are the possibilities of reducing the emissions? The world's population is increasing, and to provide food and a worthy life for everybody we have to use more energy. Where do we get this energy from without causing great climate changes and environmental changes? Should gas power plants be built in Norway? Should Swedish nuclear power plants be shut down, or is it advisable to concentrate on nuclear power, worldwide, this century, to reduce the CO{sub 2} emissions until the renewable energy sources have been developed and can take over once the petroleum sources have been depleted? The book also discusses the global magnetic field, which protects against particle radiation from space and which gives rise to the aurora borealis. The book is aimed at students taking environmental courses in universities and colleges, but is also of interest for anybody concerned about climate questions, energy sources and living standard.

  6. Trace Gases, CO2, Climate, and the Greenhouse Effect.

    Science.gov (United States)

    Aubrecht, Gordon J., II

    1988-01-01

    Reports carbon dioxide and other trace gases can be the cause of the Greenhouse Effect. Discusses some effects of the temperature change and suggests some solutions. Included are several diagrams, graphs, and a table. (YP)

  7. Miniaturized Laser Heterodyne Radiometer (LHR) for Measurements of Greenhouse Gases in the Atmospheric Column

    Science.gov (United States)

    Steel, Emily; McLinden, Matthew

    2012-01-01

    This passive laser heterodyne radiometer (LHR) instrument simultaneously measures multiple trace gases in the atmospheric column including carbon dioxide (CO2) and methane (CH4), and resolves their concentrations at different altitudes. This instrument has been designed to operate in tandem with the passive aerosol sensor currently used in AERONET (an established network of more than 450 ground aerosol monitoring instruments worldwide). Because aerosols induce a radiative effect that influences terrestrial carbon exchange, simultaneous detection of aerosols with these key carbon cycle gases offers a uniquely comprehensive measurement approach. Laser heterodyne radiometry is a technique for detecting weak signals that was adapted from radio receiver technology. In a radio receiver, a weak input signal from a radio antenna is mixed with a stronger local oscillator signal. The mixed signal (beat note, or intermediate frequency) has a frequency equal to the difference between the input signal and the local oscillator. The intermediate frequency is amplified and sent to a detector that extracts the audio from the signal. In the LHR instrument described here, sunlight that has undergone absorption by the trace gas is mixed with laser light at a frequency matched to a trace gas absorption feature in the infrared (IR). Mixing results in a beat signal in the RF (radio frequency) region that can be related to the atmospheric concentration. For a one-second integration, the estimated column sensitivities are 0.1 ppmv for CO2, and Greenhouse gases Observational SATellite). The only network that currently measures CO2 and CH4 in the atmospheric column is TCCON (Total Carbon Column Observing Network), and only two of its 16 operational sites are in the United States. TCCON data is used for validation of GOSAT data, and will be used for OCO-2 validation. While these Fourier-transform spectrometers (FTS) can measure the largest range of trace gases, the network is severely limited

  8. Increased soil emissions of potent greenhouse gases under increased atmospheric CO2.

    Science.gov (United States)

    van Groenigen, Kees Jan; Osenberg, Craig W; Hungate, Bruce A

    2011-07-13

    Increasing concentrations of atmospheric carbon dioxide (CO(2)) can affect biotic and abiotic conditions in soil, such as microbial activity and water content. In turn, these changes might be expected to alter the production and consumption of the important greenhouse gases nitrous oxide (N(2)O) and methane (CH(4)) (refs 2, 3). However, studies on fluxes of N(2)O and CH(4) from soil under increased atmospheric CO(2) have not been quantitatively synthesized. Here we show, using meta-analysis, that increased CO(2) (ranging from 463 to 780 parts per million by volume) stimulates both N(2)O emissions from upland soils and CH(4) emissions from rice paddies and natural wetlands. Because enhanced greenhouse-gas emissions add to the radiative forcing of terrestrial ecosystems, these emissions are expected to negate at least 16.6 per cent of the climate change mitigation potential previously predicted from an increase in the terrestrial carbon sink under increased atmospheric CO(2) concentrations. Our results therefore suggest that the capacity of land ecosystems to slow climate warming has been overestimated.

  9. Hydrological controls on the tropospheric ozone greenhouse gas effect

    Directory of Open Access Journals (Sweden)

    Le Kuai

    2017-03-01

    Full Text Available The influence of the hydrological cycle in the greenhouse gas (GHG effect of tropospheric ozone (O3 is quantified in terms of the O3longwave radiative effect (LWRE, which is defined as the net reduction of top-of-atmosphere flux due to total tropospheric O3absorption. The O3LWRE derived from the infrared spectral measurements by Aura’s Tropospheric Emission Spectrometer (TES show that the spatiotemporal variation of LWRE is relevant to relative humidity, surface temperature, and tropospheric O3column. The zonally averaged subtropical LWRE is ~0.2 W m-2higher than the zonally averaged tropical LWRE, generally due to lower water vapor concentrations and less cloud coverage at the downward branch of the Hadley cell in the subtropics. The largest values of O3LWRE over the Middle East (>1 W/m2 are further due to large thermal contrasts and tropospheric ozone enhancements from atmospheric circulation and pollution. Conversely, the low O3LWRE over the Inter-Tropical Convergence Zone (on average 0.4 W m-2 is due to strong water vapor absorption and cloudiness, both of which reduce the tropospheric O3absorption in the longwave radiation. These results show that changes in the hydrological cycle due to climate change could affect the magnitude and distribution of ozone radiative forcing.

  10. Greenhouse effects due to man-made perturbations of trace gases

    Science.gov (United States)

    Wang, W. C.; Yung, Y. L.; Lacis, A. A.; Mo, T.; Hansen, J. E.

    1976-01-01

    Nitrous oxide, methane, ammonia, and a number of other trace constituents of the earth's atmosphere have infrared absorption bands in the spectral range from 7 to 14 microns. Despite their small amounts, these gases can have a significant effect on the thermal structure of the atmosphere by transmitting most of the thermal radiation from the earth's surface to the lower atmosphere. In the present paper, this greenhouse effect is computed for a number of trace gases. The nature and climatic implications of possible changes in the concentrations of N2O, CH4, NH3, and HNO3 are discussed.

  11. Antarctic specific features of the greenhouse effect. A radiative analysis using measurements and models

    Energy Technology Data Exchange (ETDEWEB)

    Schmithuesen, Holger

    2014-12-10

    CO{sub 2} is the strongest anthropogenic forcing agent for climate change since pre-industrial times. Like other greenhouse gases, CO{sub 2} absorbs terrestrial surface radiation and causes emission from the atmosphere to space. As the surface is generally warmer than the atmosphere, the total long-wave emission to space is commonly less than the surface emission. However, this does not hold true for the high elevated areas of central Antarctica. For this region, it is shown that the greenhouse effect of CO{sub 2} is around zero or even negative. Moreover, for central Antarctica an increase in CO{sub 2} concentration leads to an increased long-wave energy loss to space, which cools the earth-atmosphere system. These unique findings for central Antarctica are in contrast to the well known general warming effect of increasing CO{sub 2}. The work contributes to explain the non-warming of central Antarctica since 1957.

  12. Elementary Pre-Service Teacher Perceptions of the Greenhouse Effect.

    Science.gov (United States)

    Groves, Fred H.; Pugh, Ava F.

    1999-01-01

    Expands on earlier work to examine pre-service teachers' views on environmental issues, especially global warming and the related term "greenhouse effect." Suggests that pre-service elementary teachers hold many misconceptions about environmental issues. (DDR)

  13. Greenhouse effect and climate; Effet de serre et climat

    Energy Technology Data Exchange (ETDEWEB)

    Poitou, J

    2008-04-15

    In the framework of the climatic change, the author aims to explain the phenomena of greenhouse effect. He details the historical aspects of the scientific knowledge in the domain, the gases produced, some characteristic of the greenhouse effect, the other actors which contribute to the climate, the climate simulation, the different factors of climate change since 1750 and the signs of the global heating. (A.L.B.)

  14. An atmospheric photochemical source of the persistent greenhouse gas CF4

    Science.gov (United States)

    Jubb, Aaron M.; McGillen, Max R.; Portmann, Robert W.; Daniel, John S.; Burkholder, James B.

    2015-11-01

    A previously uncharacterized atmospheric source of the persistent greenhouse gas tetrafluoromethane, CF4, has been identified in the UV photolysis of trifluoroacetyl fluoride, CF3C(O)F, which is a degradation product of several halocarbons currently present in the atmosphere. CF4 quantum yields in the photolysis of CF3C(O)F were measured at 193, 214, 228, and 248 nm, wavelengths relevant to stratospheric photolysis, to be (75.3 ± 1) × 10-4, (23.7 ± 0.4) × 10-4, (6.6 ± 0.2) × 10-4, and ≤0.4 × 10-4, respectively. A 2-D atmospheric model was used to estimate the contribution of the photochemical source to the global CF4 budget. The atmospheric photochemical production of CF4 from CF3CH2F (HFC-134a), CF3CHFCl (HCFC-124), and CF3CCl2F (CFC-114a) per molecule emitted was calculated to be (1-2.5) × 10-5, 1.0 × 10-4, and 2.8 × 10-3, respectively. Although CF4 photochemical production was found to be relatively minor at the present time, the identified mechanism demonstrates that long-lived products with potential climate impacts can be formed from the atmospheric breakdown of shorter-lived source gases.

  15. Effect of Greenhouse Gases Dissolved in Seawater.

    Science.gov (United States)

    Matsunaga, Shigeki

    2015-12-30

    A molecular dynamics simulation has been performed on the greenhouse gases carbon dioxide and methane dissolved in a sodium chloride aqueous solution, as a simple model of seawater. A carbon dioxide molecule is also treated as a hydrogen carbonate ion. The structure, coordination number, diffusion coefficient, shear viscosity, specific heat, and thermal conductivity of the solutions have been discussed. The anomalous behaviors of these properties, especially the negative pressure dependence of thermal conductivity, have been observed in the higher-pressure region.

  16. Assessment of US, Indian and Chinese Middle School Students' Outlook on the Greenhouse Effect

    Science.gov (United States)

    Niyogi, D.; Ganesh, N.; Singh, D.; Liu, X.; Shepardson, D. P.; Roychoudhury, A.; Hirsch, A.; Halversen, C.

    2012-12-01

    When you think of the greenhouse effect and climate change what images and concepts come to mind? Answers to these questions are important to educators and policy makers as they wrestle with the issue of educating and conveying these concepts in class rooms and to the general public. The greenhouse effect (GHE) sustains life on the earth through regulating the temperatures on the planet. Well-mixed greenhouse gases (GHGs) such as water vapor, carbon dioxide, methane, and nitrous oxide absorb outgoing (long wave) radiation from the Earth's surface while allowing passage without absorption of the incoming solar (shortwave) radiation. Increasing the GHG concentration in the atmosphere increases the absorption of long wavelength radiation thereby increasing global temperatures that result in changes in the atmospheric states consistently over multiple decades.The concept of the greenhouse effect is critical to the discussions underway pertaining to climate change and the controls on greenhouse emissions being proposed in different forums. This study sought to (1) investigate students' conceptions about the greenhouse effect, global warming and climate change; (2) determine if there are differences between perceptions for students in US, India and China (Asia)- where there are known differences in the political and scientific approaches; and (3) determine if there any differences, contextual or otherwise, in the way the greenhouse effect is taught in these countries. This study was conducted in select schools in the Midwest US, India and China that volunteered to work with this project. -For US, data from 51 secondary students from three different schools were analyzed, for India the number was 71 from 3 schools, while for China the number is over 100 (and being analyzed) from different classes within a school. Study Hypotheses: 1.Middle school students have a good scientific understanding of greenhouse gases. 2.The U.S and Asian students have the same outlook. Teachers

  17. Increased greenhouse-gas intensity of rice production under future atmospheric conditions

    Science.gov (United States)

    van Groenigen, Kees Jan; van Kessel, Chris; Hungate, Bruce A.

    2013-03-01

    Increased atmospheric CO2 and rising temperatures are expected to affect rice yields and greenhouse-gas (GHG) emissions from rice paddies. This is important, because rice cultivation is one of the largest human-induced sources of the potent GHG methane (CH4) and rice is the world's second-most produced staple crop. The need for meeting a growing global food demand argues for assessing GHG emissions from croplands on the basis of yield rather than land area, such that efforts to reduce GHG emissions take into consideration the consequences for food production. However, it is unclear whether or how the GHG intensity (that is, yield-scaled GHG emissions) of cropping systems will be affected by future atmospheric conditions. Here we show, using meta-analysis, that increased atmospheric CO2 (ranging from 550 to 743ppmV) and warming (ranging from +0.8°C to +6°C) both increase the GHG intensity of rice cultivation. Increased atmospheric CO2 increased GHG intensity by 31.4%, because CH4 emissions are stimulated more than rice yields. Warming increased GHG intensity by 11.8% per 1°C, largely owing to a decrease in yield. This analysis suggests that rising CO2 and warming will approximately double the GHG intensity of rice production by the end of the twenty-first century, stressing the need for management practices that optimize rice production while reducing its GHG intensity as the climate continues to change.

  18. Aerosol lidar observations of atmospheric mixing in Los Angeles: Climatology and implications for greenhouse gas observations

    Science.gov (United States)

    Ware, John; Kort, Eric A.; DeCola, Phil; Duren, Riley

    2016-08-01

    Atmospheric observations of greenhouse gases provide essential information on sources and sinks of these key atmospheric constituents. To quantify fluxes from atmospheric observations, representation of transport—especially vertical mixing—is a necessity and often a source of error. We report on remotely sensed profiles of vertical aerosol distribution taken over a 2 year period in Pasadena, California. Using an automated analysis system, we estimate daytime mixing layer depth, achieving high confidence in the afternoon maximum on 51% of days with profiles from a Sigma Space Mini Micropulse LiDAR (MiniMPL) and on 36% of days with a Vaisala CL51 ceilometer. We note that considering ceilometer data on a logarithmic scale, a standard method, introduces, an offset in mixing height retrievals. The mean afternoon maximum mixing height is 770 m Above Ground Level in summer and 670 m in winter, with significant day-to-day variance (within season σ = 220m≈30%). Taking advantage of the MiniMPL's portability, we demonstrate the feasibility of measuring the detailed horizontal structure of the mixing layer by automobile. We compare our observations to planetary boundary layer (PBL) heights from sonde launches, North American regional reanalysis (NARR), and a custom Weather Research and Forecasting (WRF) model developed for greenhouse gas (GHG) monitoring in Los Angeles. NARR and WRF PBL heights at Pasadena are both systematically higher than measured, NARR by 2.5 times; these biases will cause proportional errors in GHG flux estimates using modeled transport. We discuss how sustained lidar observations can be used to reduce flux inversion error by selecting suitable analysis periods, calibrating models, or characterizing bias for correction in post processing.

  19. Aerosol lidar observations of atmospheric mixing in Los Angeles: Climatology and implications for greenhouse gas observations.

    Science.gov (United States)

    Ware, John; Kort, Eric A; DeCola, Phil; Duren, Riley

    2016-08-27

    Atmospheric observations of greenhouse gases provide essential information on sources and sinks of these key atmospheric constituents. To quantify fluxes from atmospheric observations, representation of transport-especially vertical mixing-is a necessity and often a source of error. We report on remotely sensed profiles of vertical aerosol distribution taken over a 2 year period in Pasadena, California. Using an automated analysis system, we estimate daytime mixing layer depth, achieving high confidence in the afternoon maximum on 51% of days with profiles from a Sigma Space Mini Micropulse LiDAR (MiniMPL) and on 36% of days with a Vaisala CL51 ceilometer. We note that considering ceilometer data on a logarithmic scale, a standard method, introduces, an offset in mixing height retrievals. The mean afternoon maximum mixing height is 770 m Above Ground Level in summer and 670 m in winter, with significant day-to-day variance (within season σ = 220m≈30%). Taking advantage of the MiniMPL's portability, we demonstrate the feasibility of measuring the detailed horizontal structure of the mixing layer by automobile. We compare our observations to planetary boundary layer (PBL) heights from sonde launches, North American regional reanalysis (NARR), and a custom Weather Research and Forecasting (WRF) model developed for greenhouse gas (GHG) monitoring in Los Angeles. NARR and WRF PBL heights at Pasadena are both systematically higher than measured, NARR by 2.5 times; these biases will cause proportional errors in GHG flux estimates using modeled transport. We discuss how sustained lidar observations can be used to reduce flux inversion error by selecting suitable analysis periods, calibrating models, or characterizing bias for correction in post processing.

  20. Possible future scenarios for atmospheric concentration of greenhouse gases. A simplified thermodynamic approach

    Energy Technology Data Exchange (ETDEWEB)

    Angulo-Brown, F.; Sanchez-Salas, N. [Departamento de Fisica, Escuela Superior de Fisica y Matematicas, del IPN Edif. 9, U.P. Zacatenco, 07738 Mexico, D.F. (Mexico); Barranco-Jimenez, M.A. [Departamento de Ciencias Basicas, Escuela Superior de Computo, del IPN Av., Miguel Bernard s/n., Esq. Juan de Dios Batiz, U.P. Zacatenco, 07738 Mexico, D.F. (Mexico); Rosales, M.A. [Departamento de Fisica y Matematicas, Universidad de las Americas Puebla, Exhacienda Sta., Catarina Martir, Cholula 72820, Puebla (Mexico)

    2009-11-15

    Most of the increase in concentrations of greenhouse gases in the Earth's atmosphere is mainly due to anthropogenic activities. This is particularly significant in the case of CO{sub 2}. The atmospheric concentration of CO{sub 2} has systematically increased since the Industrial Revolution (260 ppm), with a remarkable raise after the 1970s until the present day (380 ppm). If this increasing tendency is maintained, the last report of the Intergovernmental Panel on Climate Change (IPCC) estimates that, for the year 2100, the CO{sub 2} concentration can augment up to approximately 675 ppm. In this work it is assumed that the quantity of anthropogenic greenhouse gases emitted to the Earth's atmosphere is proportional to the quantity of heat rejected to the environment by internal combustion heat engines. It is also assumed that this increasing tendency of CO{sub 2} due to men's activity stems from a mode of energy production mainly based on a maximum-power output paradigm. With these hypotheses, a thermoeconomic optimization of a thermal engine model under two regimes of performance: the maximum-power regime and the so-called ecological function criterion is presented. This last regime consists in maximizing a function that represents a good compromise between high power output and low entropy production. It is showed that, under maximum ecological conditions, the emissions of thermal energy to the environment are reduced approximately up to 50%. Thus working under this mode of performance the slope of the curves of CO{sub 2} concentration, for instance, drastically diminishes. A simple qualitative criterion to design ecological taxes is also suggested. (author)

  1. Habitability of waterworlds: runaway greenhouses, atmospheric expansion and multiple climate states of pure water atmospheres

    CERN Document Server

    Goldblatt, Colin

    2015-01-01

    There are four different stable climate states for pure water atmospheres, as might exist on so-called "waterworlds". I map these as a function of solar constant for planets ranging in size from Mars size to 10 Earth-mass. The states are: globally ice covered (Ts< 245K), cold and damp (270 < Ts< 290K), hot and moist (350< Ts< 550K) and very hot and dry (Ts< 900K). No stable climate exists for 290< Ts < 350K or 550 < Ts < 900K. The union of hot moist and cold damp climates describe the liquid water habitable zone, the width and location of which depends on planet mass. At each solar constant, two or three different climate states are stable. This is a consequence of strong non-linearities in both thermal emission and the net absorption of sunlight. Across the range of planet sizes, I account for the atmospheres expanding to high altitudes as they warm. The emitting and absorbing surfaces (optical depth of unity) move to high altitude, making their area larger than the planet surfa...

  2. The clear-sky greenhouse effect sensitivity to a sea surface temperature change

    Science.gov (United States)

    Duvel, J. PH.; Breon, F. M.

    1991-01-01

    The clear-sky greenhouse effect response to a sea surface temperature (SST or Ts) change is studied using outgoing clear-sky longwave radiation measurements from the Earth Radiation Budget Experiment. Considering geographical distributions for July 1987, the relation between the SST, the greenhouse effect (defined as the outgoing infrared flux trapped by atmospheric gases), and the precipitable water vapor content (W), estimated by the Special Sensor Microwave Imager, is analyzed first. A fairly linear relation between W and the normalized greenhouse effect g, is found. On the contrary, the SST dependence of both W and g exhibits nonlinearities with, especially, a large increase for SST above 25 C. This enhanced sensitivity of g and W can be interpreted in part by a corresponding large increase of atmospheric water vapor content related to the transition from subtropical dry regions to equatorial moist regions. Using two years of data (1985 and 1986), the normalized greenhouse effect sensitivity to the sea surface temperature is computed from the interannual variation of monthly mean values.

  3. The state of greenhouse gases in the atmosphere using global observations through 2013

    Science.gov (United States)

    Tarasova, Oksana; Koide, Hiroshi; Dlugokencky, Ed; Montzka, Stephen A.; Keeling, Ralph; Tanhua, Toste; Lorenzoni, Laura

    2015-04-01

    We present results from the tenth annual Greenhouse Gas Bulletin (http://www.wmo.int/pages/prog/arep/gaw/ ghg/GHGbulletin.html) of the World Meteorological Organization (WMO). The results are based on research and observations performed by laboratories contributing to the WMO Global Atmosphere Watch (GAW) Programme (www.wmo.int/gaw). The Bulletin presents results of global analyses of observational data collected according to GAW recommended practices and submitted to the World Data Center for Greenhouse Gases (WDCGG), and for the first time, it includes a summary of ocean acidification. Bulletins are prepared by the WMO/GAW Scientific Advisory Group for Greenhouse Gases (http://www.wmo.int/pages/prog/arep/gaw/ScientificAdvisoryGroups.html) in collaboration with WDCGG. The summary of ocean acidification and trends in ocean pCO2 was jointly produced by the International Ocean Carbon Coordination Project (IOCCP) of the Intergovernmental Oceanographic Commission of UNESCO (IOC-UNESCO), the Scientific Committee on Oceanic Research (SCOR), and the Ocean Acidification International Coordination Centre (OA-ICC) of the International Atomic Energy Agency (IAEA). The tenth Bulletin included a special edition published prior to the United Nations Climate Summit in September 2014. The scope of this edition was to demonstrate the level of emission reduction necessary to stabilize radiative forcing by long-lived greenhouse gases. It shows in particular that a reduction in radiative forcing from its current level (2.92 W m-2 in 2013) requires significant reductions in anthropogenic emissions of all major greenhouse gases. Observations used for global analysis are collected at more than 100 marine and terrestrial sites worldwide for CO2 and CH4 and at a smaller number of sites for other greenhouse gases. Globally averaged dry-air mole fractions of carbon dioxide, methane and nitrous oxide derived from this network reached new highs in 2013, with CO2 at 396.0 ± 0.1 ppm, CH4 at

  4. Effect of Greenhouse Gases Dissolved in Seawater

    Directory of Open Access Journals (Sweden)

    Shigeki Matsunaga

    2015-12-01

    Full Text Available A molecular dynamics simulation has been performed on the greenhouse gases carbon dioxide and methane dissolved in a sodium chloride aqueous solution, as a simple model of seawater. A carbon dioxide molecule is also treated as a hydrogen carbonate ion. The structure, coordination number, diffusion coefficient, shear viscosity, specific heat, and thermal conductivity of the solutions have been discussed. The anomalous behaviors of these properties, especially the negative pressure dependence of thermal conductivity, have been observed in the higher-pressure region.

  5. Lake-Atmosphere Greenhouse Gas Exchange in Relation to Atmospheric Forcing and Water Clarity

    Science.gov (United States)

    Heiskanen, J. J.; Ojala, A.; Mammarella, I.; Vesala, T.

    2015-12-01

    Even though lakes cover only 2 % of the world's land surface, it has been estimated that lakes release about 10 % of the carbon fixed annually by the terrestrial ecosystems back to the atmosphere. A critical parameter in the gas exchange estimates is the gas transfer velocity (k), which is governed by turbulence. The aim of our study was to assess the current global CO2 evasion estimates from lakes to the atmosphere by comparing parameterizations for kand the significance of wind and heat flux to the gas transfer in small lakes. To improve future predictions of gas evasion from lakes, we focused on the changes in water clarity and how they affect water column physics and processes in the air-water interface. We studied a small boreal lake and used the eddy covariance (EC) method for the high precision data needed, and therefore also aimed to improve the EC methodology on lakes. The air-water gas transfer was related to both wind and heat loss during times of seasonal stratification, but only to wind during autumn overturn. When wind-induced thermocline tilting and resulting spatial variability in surface water CO2 concentrations was accounted for, average k derived from the measurements dropped from 6.0 cm h-1 to 5.2 cm h-1. This was still over twice the estimate (2.2 cm h-1) calculated with a widely used model for kin lakes suggesting that the global estimates of gas evasion from lakes might be underestimations. Water clarity was a significant parameter defining the thermal stratification of the lake: a change from clear to dark water would lead to shorter stratification period and lower water column temperatures in small lakes and therefore have significant impact on the lake-atmosphere exchange processes. Figure 1. The isotherms of Lake Kuivajärvi throughout the open-water period 2013. The top left are the measured temperatures and the others are modeled with LAKE model using fixed light extinction coefficient, Kd. The horizontal dashed black line represents

  6. Greenhouse effect of trace gases, 1970-1980

    Science.gov (United States)

    Lacis, A.; Hansen, J.; Lee, P.; Lebedeff, S.; Mitchell, T.

    1981-01-01

    Increased abundances were measured for several trace atmospheric gases in the decade 1970-1980. The equilibrium greenhouse warming for the measured increments of CH4, chlorofluorocarbons and N2O is between 50% and 100% of the equilibrium warming for the measured increase of atmospheric CO2 during the same 10 years. The combined warming of CO2 and trace gases should exceed natural global temperature variability in the 1980's and cause the global mean temperature to rise above the maximum of the late 1930's.

  7. Detecting Methane From Leaking Pipelines and as Greenhouse Gas in the Atmosphere

    Science.gov (United States)

    Riris, Haris; Numata, Kenji; Li, Steven; Wu, Stewart; Ramanathan, Anand; Dawsey, Martha

    2012-01-01

    Laser remote sensing measurements of trace gases from orbit can provide unprecedented information about important planetary science and answer critical questions about planetary atmospheres. Methane (CH4) is the second most important anthropogenically produced greenhouse gas. Though its atmospheric abundance is much less than that of CO2 (1.78 ppm vs. 380 ppm), it has much larger greenhouse heating potential. CH4 also contributes to pollution in the lower atmosphere through chemical reactions, leading to ozone production. Atmospheric CH4 concentrations have been increasing as a result of increased fossil fuel production, rice farming, livestock, and landfills. Natural sources of CH4 include wetlands, wild fires, and termites, and perhaps other unknown sources. Important sinks for CH4 include non-saturated soils and oxidation by hydroxyl radicals in the atmosphere. Remotely measuring CH4 and other biogenic molecules (such as ethane and formaldehyde) on Mars also has important implications on the existence of life on Mars. Measuring CH4 at very low (ppb) concentrations from orbit will dramatically improve the sensitivity and spatial resolution in the search for CH4 vents and sub-surface life on other planets. A capability has been developed using lasers and spectroscopic detection techniques for the remote measurements of trace gases in open paths. Detection of CH4, CO2, H2O, and CO in absorption cells and in open paths, both in the mid- IR and near-IR region, has been demonstrated using an Optical Parametric Amplifier laser transmitter developed at GSFC. With this transmitter, it would be possible to develop a remote sensing methane instrument. CH4 detection also has very important commercial applications. Pipeline leak detection from an aircraft or a helicopter can significantly reduce cost, response time, and pinpoint the location. The main advantage is the ability to rapidly detect CH4 leaks remotely. This is extremely important for the petrochemical industry

  8. Swedish contribution to the greenhouse effect and required reductions to meet the 550 ppmv target

    Energy Technology Data Exchange (ETDEWEB)

    Lindell, Lina; Nilsson, Kristina [Uppsala Univ. (Sweden). School of Engineering

    2002-11-01

    According to the Swedish Parliament, the Swedish international climate strategy should focus on a stabilisation of the concentration of greenhouse gases in the atmosphere. An equilibrium concentration lower than 550 ppmv CO{sub 2}-equivalents should be achieved by the end of this century. As an interim target, the yearly emissions should not exceed 4.5 tonnes CO{sub 2}-equivalents per capita by 2050. In this study an inventory of Swedish emissions from 1834 until 2000, for the six greenhouse gases regulated by the Kyoto Protocol, is carried out. Future emission scenarios for carbon dioxide during the time period 2000-2050 are also defined. This data is used for estimating the contribution to the greenhouse effect both today and in the future. Further it is investigated if the 2050-target is sufficient for not exceeding an atmospheric concentration of 550 ppmv. The required reduction for 2100 to reach an equilibrium concentration below this level is also estimated. The Swedish contribution to the greenhouse effect today is about 30 % larger than it should be according to the fairness factor used in this study. The Swedish emission target set for 2050 is sufficient for not exceeding 550 ppmv by that year. However, to reach a stabilisation of the concentration below this level the emissions have to be reduced to 1.0-1.5 tonnes CO{sub 2}-equivalents per capita by 2100.

  9. Greenhouse effect from the point of view of radiative transfer

    CERN Document Server

    Barcza, Szabolcs

    2016-01-01

    Radiative power balance of a planet in the solar system is delineated. The terrestrial powers are transformed to average global flux in an effective atmospheric column (EAC) approximation, its components are delineated. The estimated and measured secular changes of the average global flux are compared to the fluxes derived from the Stefan-Boltzmann law using the observed global annual temperatures in the decades between 1880 and 2010. The conclusion of this procedure is that the radiative contribution of the greenhouse gas ${\\rm CO}_2$ is some $21\\pm 7$~\\% to the observed global warming from the end of the XIXth century excluding the feedback mechanisms playing determining role in the climate system. Stationary radiative flux transfer is treated in an air column as a function of the column density of the absorbent. Upper and lower limit of radiative forcing is given by assuming true absorption and coherent scatter of the monochromatic radiation. An integral formula is given for the outgoing long wave radiatio...

  10. The Berkeley Atmospheric CO2 Observation Network (BEACON): Measuring Greenhouse Gases and Criteria Pollutants within the Urban Dome

    Science.gov (United States)

    Teige, V. E.; Weichsel, K.; Hooker, A.; Wooldridge, P. J.; Cohen, R. C.

    2012-12-01

    Efforts to curb greenhouse gas emissions, while global in their impacts, often focus on local and regional scales for execution and are dependent on the actions of communities and individuals. Evaluating the effectiveness of local policies requires observations with much higher spatial resolution than are currently available---kilometer scale. The Berkeley Atmospheric CO2 Observation Network (BEACON):, launched at the end of 2011, aims to provide measurements of urban-scale concentrations of CO2, temperature, pressure, relative humidity, O3, CO, and NO2 with sufficient spatial and temporal resolution to characterize the sources of CO2 within cities. Our initial deployment in Oakland, California uses ~40 sensor packages at a roughly 2 km spacing throughout the city. We will present an initial analysis of the vertical gradients and other spatial patterns observed to date.

  11. Climate and site management as driving factors for the atmospheric greenhouse gas exchange of a restored wetland

    Directory of Open Access Journals (Sweden)

    M. Herbst

    2013-01-01

    Full Text Available The atmospheric greenhouse gas (GHG budget of a restored wetland in western Denmark was established for the years 2009–2011 from eddy covariance measurements of carbon dioxide (CO2 and methane (CH4 fluxes. The water table in the wetland, which was restored in 2002, was unregulated, and the vegetation height was limited through occasional grazing by cattle and grass cutting. The annual net CO2 uptake varied between 195 and 983 g m−2 and the annual net CH4 release varied between 11 and 17 g m−2. In all three years the wetland was a carbon sink and removed between 42 and 259 g C m−2 from the atmosphere. However, in terms of the full annual GHG budget (assuming that 1 g CH4 is equivalent to 25 g CO2 with respect to the greenhouse effect over a time horizon of 100 years the wetland was a sink in 2009, a source in 2010 and neutral in 2011. Complementary observations of meteorological factors and management activities were used to explain the large inter-annual variations in the full atmospheric GHG budget of the wetland. The largest impact on the annual GHG fluxes, eventually defining their sign, came from site management through changes in grazing duration and animal stocking density. These changes accounted for half of the observed variability in the CO2 fluxes and about two thirds of the variability in CH4 fluxes. An unusually long period of snow cover in 2010 had the second largest effect on the annual CO2 flux, whose interannual variability was larger than that of the CH4 flux. Since integrated CO2 and CH4 flux data from restored wetlands are still very rare, it is concluded that more long-term flux measurements are needed to quantify the effects of ecosystem disturbance, in terms of management activities and exceptional weather patterns, on the atmospheric GHG budget more

  12. Biological methanogenesis and the CO2 greenhouse effect

    Science.gov (United States)

    Guthrie, P. D.

    1986-01-01

    It is well established that plants tend to increase net photosynthesis under increased carbon dioxide. It is also well established that a large fraction of atmospheric methane is produced by microbial metabolism of organic sediments in paddies and freshwater wetlands, where a major source of organic debris is local plant growth. As CO2 increases, it may lead to increased methane production and a resulting enhancement of the expected greenhouse warming. A rough estimate of the present rate of this biologically mediated feedback on the climate system indicates that it might account for as much as 30 percent of the observed methane increase and speed up the greenhouse forcing by as much as 15 percent.

  13. Knowledge about the 'Greenhouse Effect': Have College Students Improved?

    Science.gov (United States)

    Jeffries, Helen; Stanisstreet, Martin; Boyes, Edward

    2001-01-01

    The ideas of Year I undergraduate biology students about the consequences, causes, and cures of the 'greenhouse effect' was determined using a closed-form questionnaire, and results were compared with a parallel study undertaken nearly 10 years ago. Many of the students in the present survey were unaware of the potential effect of global warming…

  14. Demonstration of the greenhouse effect for elementary school students

    Science.gov (United States)

    Radovanovic, Jelena

    2014-05-01

    The school where I work is part of the "Step by step towards the sustainable development school" project. Project activities are partly directed towards the popularization of science. As a physics teacher, I have had the opportunity to engage in designing interactive workshops, aiming to introduce younger students to simple experiments which illustrate different natural phenomena, and also in organization, preparation and implementation of school and city science festival (in 2012 and 2013). Numerous displays, workshops and experiments served to introduce a large number of visitors to different topics in the area of science and technology. One of the subjects of forthcoming science festival, planned for May of 2014, is the climate change. To that effect, eight grade students will hold a demonstration and explanation of the greenhouse effect. Although the terms greenhouse effect and global warming are widely used in media, most of the elementary school students in Serbia have poor understanding of the underlying scientific concepts. The experiment with analysis and discussion will first be implemented in one eight-grade class (14 years of age). After that, a group of students from this class will present their newly-acquired knowledge to their peers and younger students at the science fair. Activity objectives: • Explain how atmosphere affects the surface temperature of Earth • Conduct an experiment to demonstrate the greenhouse effect • Analyze the consequences of climate changes Experiment description: Take two empty, transparent containers and add a layer of garden soil. Use cardboard or similar material to make housings for the thermometers. Hang them in the containers, so that they don't touch the soil. Cover one container with a glass panel, and leave the other one open. Place identical incandescent light bulbs at the same distance above each container. Turn the light bulbs on. The students should mark the thermometer readings every 2 minutes, for 20

  15. Carbonation of alkaline paper mill waste to reduce CO{sub 2} greenhouse gas emissions into the atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Lopez, R. [Laboratoire de Geophysique Interne et Tectonophysique, CNRS-OSUG-UJF, Universite Joseph Fourier Grenoble I, Maison des Geosciences, BP 53, 38041 Grenoble Cedex (France); Department of Geology, University of Huelva, Campus ' El Carmen' , 21071 Huelva (Spain)], E-mail: rafael.perez@dgeo.uhu.es; Montes-Hernandez, G. [Laboratoire de Geophysique Interne et Tectonophysique, CNRS-OSUG-UJF, Universite Joseph Fourier Grenoble I, Maison des Geosciences, BP 53, 38041 Grenoble Cedex (France); Nieto, J.M. [Department of Geology, University of Huelva, Campus ' El Carmen' , 21071 Huelva (Spain); Renard, F. [Laboratoire de Geodynamique des Chaines Alpines, CNRS-OSUG-UJF, Universite Joseph Fourier Grenoble I, Maison des Geosciences, BP 53, 38041 Grenoble Cedex (France); Physics of Geological Processes, University of Oslo (Norway); Charlet, L. [Laboratoire de Geophysique Interne et Tectonophysique, CNRS-OSUG-UJF, Universite Joseph Fourier Grenoble I, Maison des Geosciences, BP 53, 38041 Grenoble Cedex (France)

    2008-08-15

    The global warming of Earth's near-surface, air and oceans in recent decades is a direct consequence of anthropogenic emission of greenhouse gases into the atmosphere such as CO{sub 2}, CH{sub 4}, N{sub 2}O and CFCs. The CO{sub 2} emissions contribute approximately 60% to this climate change. This study investigates experimentally the aqueous carbonation mechanisms of an alkaline paper mill waste containing about 55 wt% portlandite (Ca(OH){sub 2}) as a possible mineralogical CO{sub 2} sequestration process. The overall carbonation reaction includes the following steps: (1) Ca release from portlandite dissolution, (2) CO{sub 2} dissolution in water and (3) CaCO{sub 3} precipitation. This CO{sub 2} sequestration mechanism was supported by geochemical modelling of final solutions using PHREEQC software, and observations by scanning electron microscope and X-ray diffraction of final reaction products. According to the experimental protocol, the system proposed would favour the total capture of approx. 218 kg of CO{sub 2} into stable calcite/ton of paper waste, independently of initial CO{sub 2} pressure. The final product from the carbonation process is a calcite (ca. 100 wt%)-water dispersion. Indeed, the total captured CO{sub 2} mineralized as calcite could be stored in degraded soils or even used for diverse industrial applications. This result demonstrates the possibility of using the alkaline liquid-solid waste for CO{sub 2} mitigation and reduction of greenhouse effect gases into the atmosphere.

  16. Health effects of predatory beneficial mites and wasps in greenhouses

    DEFF Research Database (Denmark)

    Bælum, Jesper; Enkegaard, Annie; Doekes, Gert

    2007-01-01

    A three-year study of 579 greenhouse workers in 31 firms investigated the effect of four different beneficial arthropods. It was shown that the thrips mite Amblyseeius cucumeris and the spider mite predator Phytoseiulus persimilis may cause allergy measured by blood tests as well as eye and nose...

  17. Exploring the Greenhouse Effect through Physics-Oriented Activities

    Science.gov (United States)

    Browne, Kerry P.; Laws, Priscilla W.

    2003-01-01

    We are developing a new activity-based unit on global warming and the environment as part of the "Explorations in Physics Curriculum." We describe the current status of this unit, which focuses on helping students understand the greenhouse effect and its relationship to global warming. We outline several problems encountered in testing the unit…

  18. Seventh Grade Students' Mental Models of the Greenhouse Effect

    Science.gov (United States)

    Shepardson, Daniel P.; Choi, Soyoung; Niyogi, Dev; Charusombat, Umarporn

    2011-01-01

    This constructivist study investigates 225 student drawings and explanations from three different schools in the midwest in the US, to identify seventh grade students' mental models of the greenhouse effect. Five distinct mental models were derived from an inductive analysis of the content of the students' drawings and explanations: Model 1, a…

  19. The Physics behind a Simple Demonstration of the Greenhouse Effect

    Science.gov (United States)

    Buxton, Gavin A.

    2014-01-01

    A simple, and popular, demonstration of the greenhouse effect involves a higher temperature being observed in a container with an elevated concentration of CO[subscript 2] inside than in a container with just air enclosed, when subject to direct light. The CO[subscript 2] absorbs outgoing thermal radiation and causes the air inside the container…

  20. Reply to "Comment on 'Cosmic-ray-driven reaction and greenhouse effect of halogenated molecules: Culprits for atmospheric ozone depletion and global climate change' by Dana Nuccitelli et al."

    Science.gov (United States)

    Lu, Q.-B.

    2014-04-01

    In the Comment by Nuccitelli et al., they make many false and invalid criticisms of the CFC-warming theory in my recent paper, and claim that their anthropogenic forcings including CO2 would provide a better explanation of the observed global mean surface temperature (GMST) data over the past 50 years. First, their arguments for no significant discrepancy between modeled and observed GMST changes and for no pause in recent global warming contradict the widely accepted fact and conclusion that were reported in the recent literature extensively. Second, their criticism that the key data used in my recent paper would be "outdated" and "flawed" is untrue as these data are still used in the recent or current literature including the newest (2013) IPCC Report and there is no considerable difference between the UK Met Office HadRCUT3 and HadRCUT4 GMST datasets. The use of even more recently computer-reconstructed total solar irradiance data (whatever have large uncertainties) for the period prior to 1976 would not change any of the conclusions in my paper, where quantitative analyses were emphasized on the influences of humans and the Sun on global surface temperature after 1970 when direct measurements became available. For the latter, the solar effect has been well shown to play only a negligible role in global surface temperature change since 1970, which is identical to the conclusion made in the 2013 IPCC Report. Third, their argument that the solar effect would not play a major role in the GMST rise of 0.2°C during 1850-1970 even contradicts the data and conclusion presented in a recent paper published in their Skeptical Science by Nuccitelli himself. Fourth, their comments also indicate their lack of understandings of the basic radiation physics of the Earth system as well as of the efficacies of different greenhouse gases in affecting global surface temperature. Their listed "methodological errors" are either trivial or non-existing. Fifth, their assertion that

  1. INFLUENCE OF AGRICULTURAL POLLUTANTS ON THE GREENHOUSE EFFECT

    Directory of Open Access Journals (Sweden)

    B. LIXANDRU

    2013-12-01

    Full Text Available The general heating of our planet has become a proved fact today, and its consequences are observed in more climatic disturbances which affect almost the whole Earth. At the base of this climatic process there is the excessive development of the greenhouse effect. The greenhouse effect is a natural physical phenomenon which has gradually developed with the geophysical and biological evolution of the Earth, and its consequence is the thermical constancy of +150C as medium global temperature. The main physical factories which contribute at the realization of greenhouse effect are CO2, watery vapors, NOx and CH4. Naturally, the greenhouse gases have the perfectly global self-regulation cycles. This capacity of self-regulation seems to be troubled by the huge amounts of polluted gaseous thrown in the air by different and usual human activities. In this sense, the agriculture has an important role and the main pollution sources are the rice plantations, inorganic fertilizations and animal farms.

  2. REVISITING THE SCATTERING GREENHOUSE EFFECT OF CO{sub 2} ICE CLOUDS

    Energy Technology Data Exchange (ETDEWEB)

    Kitzmann, D., E-mail: daniel.kitzmann@csh.unibe.ch [Center for Space and Habitability, University of Bern, Sidlerstr. 5, 3012 Bern (Switzerland)

    2016-02-01

    Carbon dioxide ice clouds are thought to play an important role for cold terrestrial planets with thick CO{sub 2} dominated atmospheres. Various previous studies showed that a scattering greenhouse effect by carbon dioxide ice clouds could result in a massive warming of the planetary surface. However, all of these studies only employed simplified two-stream radiative transfer schemes to describe the anisotropic scattering. Using accurate radiative transfer models with a general discrete ordinate method, this study revisits this important effect and shows that the positive climatic impact of carbon dioxide clouds was strongly overestimated in the past. The revised scattering greenhouse effect can have important implications for the early Mars, but also for planets like the early Earth or the position of the outer boundary of the habitable zone.

  3. Soil-atmosphere greenhouse-gas exchange in a bioretention system

    Science.gov (United States)

    Daly, E.; Chan, H.; Beringer, J.; Livesley, S. J.

    2011-12-01

    Bioretention systems are a popular green-technology for the management of urban stormwater runoff in many countries. They typically consist of a trench filled with a highly permeable soil medium that supports vegetation; runoff is diverted to bioretention systems and, by percolating through the filter medium, is subjected to a number of treatment processes. Nitrogen (N) is one of the key pollutants targeted by bioretention systems, which are able to reduce N concentrations considerably from inflow to outflow. To increase N removal, a saturated zone at the bottom of the filter medium is often artificially generated, to both enhance the denitrification process and increase the water available to the vegetation between inflow events. Although studies on the N-removal performance of bioretention systems are widely available in the literature, less is known about the exchange of greenhouse gases (GHG), especially nitrous oxide (N2O), between the bioretention systems and the atmosphere. Here, we present an experimental pilot study to measure N2O and CO2 soil emissions in a bioretention system installed on the Clayton Campus of Monash University in Melbourne, Australia. The bioretention system is divided into three cells, each 15 m2; the system as a whole receives water run-off from 4500 m2 of impervious car park. We monitored two cells with mostly sandy-loam vegetated with native sedges (mainly Carex Appressa and Lomandra Longifolia), one with and one without a saturated zone. Three manual flux chambers were installed in both cells. Gas flux samples were taken twice a week at about 11 am between the 2nd of March and the 18th of May 2011 (late summer and fall). Since October 2010, air-phase soil CO2 concentration profiles were measured continuously using solid-state infrared CO2 transmitters (GMT-221 model, Vaisala, Finland), along with soil moisture and soil temperature. Preliminary analysis of the chamber data (March only) showed that N2O fluxes were in general below 50

  4. Health effects of predatory beneficial mites and wasps in greenhouses

    DEFF Research Database (Denmark)

    Bælum, Jesper; Enkegaard, Annie; Doekes, Gert;

    A three-year study of 579 greenhouse workers in 31 firms investigated the effect of four different beneficial arthropods. It was shown that the thrips mite Amblyseeius cucumeris and the spider mite predator Phytoseiulus persimilis may cause allergy measured by blood tests as well as eye and nose...... symptoms. No effect was seen by the predator wasp Aphidius colemani nor the predator mite Hypoaspis miles and no effect on lung diseases were seen....

  5. The greenhouse effect: will we change the climate?; L'effet de serre: allons-nous changer le climat?

    Energy Technology Data Exchange (ETDEWEB)

    Le Treut, H

    2004-07-01

    This book presents the great climate factors, the changes resulting from the greenhouse effect and the corresponding human factors part, the atmosphere chemical composition and the biological and geo-political risks bound to the climatic changes. (A.L.B.)

  6. THE INTEGRITY OF THE ICE RECORD OF GREENHOUSE GASES WITH A SPECIAL FOCUS ON ATMOSPHERIC CO2

    Directory of Open Access Journals (Sweden)

    Dominique Raynaud

    2012-01-01

    Full Text Available Over the last 25 years, the ice core record has provided a unique and precious archive of past changes in three important greenhouse gases: carbon dioxide CO2, methane CH4 and nitrous oxide N2O. Recovering the Vostok ice core has played a major role, being the first ice record showing the variations of CO2 and CH4 during a full glacial-interglacial cycle, and a few years later being extended to three more cycles. This information, by revealing the tight coupling between climate and carbon cycle during the last glacial-interglacial cycles, has become a benchmark against which climate and carbon cycle models can be tested. The purpose of the present work is to discuss the degree of integrity of the ice core record of greenhouse gases and to assess to which degree it provides an accurate reconstruction of the past atmospheric changes. The various processes potentially affecting the integrity of the record are discussed. They include the interactions of trace gases with precipitation or firn grains, the effect of summer-melting at the surface of the ice sheet, the diffusion and the gravitational setting of gases in the open spaces of the firn, the physical, chemical and biological interactions between the air trapped and the ice matrix, the role of the transformation of air bubbles into air hydrates with depth in the ice column. Providing to select an appropriate sampling site, to take specific precautions during storage and transportation of the ice cores, and to select ice of good quality, the ice core record of initial atmospheric gases is hardly affected by the processes listed above. Such conclusion is strongly supported by the remarkable agreement of global signals like CO2 or CH4 measured in different cores taken at different locations. Finally, I bring back here the history of how the ice core record of atmospheric CO2 has been obtained, from the pioneering times to today, and summarize the main conclusions reached in terms of climate

  7. Toward reconciling the influence of atmospheric aerosols and greenhouse gases on light precipitation changes in Eastern China: AEROSOLS AND GREENHOUSE GASES

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yuan [Jet Propulsion Laboratory, California Institute of Technology, Pasadena California USA; Ma, Po-Lun [Pacific Northwest National Laboratory, Richland Washington USA; Jiang, Jonathan H. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena California USA; Su, Hui [Jet Propulsion Laboratory, California Institute of Technology, Pasadena California USA; Rasch, Philip J. [Pacific Northwest National Laboratory, Richland Washington USA

    2016-05-21

    The attribution of the widely observed shifted precipitation extremes to different forcing agents represents a critical issue for understanding of changes in the hydrological cycle. To compare aerosol and greenhouse-gas effects on the historical trends of precipitation intensity, we performed AMIP-style NCAR/DOE CAM5 model simulations from 1950-2005 with and without anthropogenic aerosol forcings. Precipitation rates at every time step in CAM5 are used to construct precipitation probability distribution functions. By contrasting the two sets of experiments, we found that the global warming induced by the accumulating greenhouse gases is responsible for the changes in precipitation intensity at the global scale. However, regionally over the Eastern China, the drastic increase in anthropogenic aerosols primarily accounts for the observed light precipitation suppression since the 1950s. Compared with aerosol radiative effects, aerosol microphysical effect has a predominant role in determining the historical trends of precipitation intensity in Eastern China.

  8. The Mechanical Greenhouse: Burial of Heat by Turbulence in Hot Jupiter Atmospheres

    CERN Document Server

    Youdin, Andrew N

    2010-01-01

    The intense irradiation received by hot Jupiters suppresses convection in the outer layers of their atmospheres and lowers their cooling rates. "Inflated" hot Jupiters, i.e., those with anomalously large transit radii, require additional sources of heat or suppressed cooling. We consider the effect of forced turbulent mixing in the radiative layer, which could be driven by atmospheric circulation or by another mechanism. Due to stable stratification in the atmosphere, forced turbulence drives a downward flux of heat. Weak turbulent mixing slows the cooling rate by this process, as if the planet was irradiated more intensely. Stronger turbulent mixing buries heat into the convective interior, provided the turbulence extends to the radiative-convective boundary. This inflates the planet until a balance is reached between the heat buried into and radiated from the interior. We also include the direct injection of heat due to the dissipation of turbulence or other effects. Such heating is already known to slow pl...

  9. Estimation of the atmosphere-ocean fluxes of greenhouse gases and aerosols at the finer resolution of the coastal ocean.

    Science.gov (United States)

    Vieira, Vasco; Sahlée, Erik; Jurus, Pavel; Clementi, Emanuela; Pettersson, Heidi; Mateus, Marcos

    2016-04-01

    The balances and fluxes of greenhouse gases and aerosols between atmosphere and ocean are fundamental for Earth's heat budget. Hence, the scientific community needs to know and simulate them with accuracy in order to monitor climate change from Earth-Observation satellites and to produce reliable estimates of climate change using Earth-System Models (ESM). So far, ESM have represented earth's surface with coarser resolutions so that each cell of the marine domain is dominated by the open ocean. In such case it is enough to use simple algorithms considering the wind speed 10m above sea-surface (u10) as sole driver of the gas transfer velocity. The formulation by Wanninkhof (1992) is broadly accepted as the best. However, the ESM community is becoming increasingly aware of the need to model with finer resolutions. Then, it is no longer enough to only consider u10 when modelling gas transfer velocities across the coastal oceans' surfaces. More comprehensive formulations are required that adjust better to local conditions by also accounting for the effects of sea-surface agitation, wave breaking, atmospheric stability of the Surface Boundary Layer, current drag with the bottom, surfactants and rain. Accurate algorithms are also fundamental to monitor atmosphere and ocean greenhouse gas concentrations using satellite data and reverse modelling. Past satellite missions ERS, Envisat, Jason-2, Aqua, Terra and Metop, have already been remotely sensing the ocean's surface at much finer resolutions than ESM using instruments like MERIS, MODIS, AMR, AATSR, MIPAS, Poseidon-3, SCIAMACHY, SeaWiFS, and IASI. The planned new satellite missions Sentinel-3, OCO-2 and GOSAT will further increase the resolutions. We developed a framework to congregate competing formulations for the estimation of the solubility and transfer velocity of virtually any gas on the biosphere taking into consideration the atmosphere and ocean fundamental variables and their derived geophysical processes

  10. Children's Models of Understanding of Two Major Global Environmental Issues (Ozone Layer and Greenhouse Effect).

    Science.gov (United States)

    Boyes, Edward; Stanisstreet, Martin

    1997-01-01

    Aims to quantify the models that 13- and 14 year-old students hold about the causes of the greenhouse effect and ozone layer depletion. Assesses the prevalence of those ideas that link the two phenomena. Twice as many students think that holes in the ozone layer cause the greenhouse effect than think the greenhouse effect causes ozone depletion.…

  11. Potential effects of anthropogenic greenhouse gases on avian habitats and populations in the northern Great Plains

    Science.gov (United States)

    Larson, Diane L.

    1994-01-01

    Biotic response to the buildup of greenhouse gases in Earth's atmosphere is considerably more complex than an adjustment to changing temperature and precipitation. The fertilization effect carbon dioxide has on some plants, the impact UVB radiation has on health and productivity of organisms, and the resulting changes in competitive balance and trophic structure must also be considered. The intent of this paper is to review direct and indirect effects of anthropogenic greenhouse gases on wildlife, and to explore possible effects on populations of birds and their habitats in the northern Great Plains.Many of the potential effects of increasing greenhouse gases, such as declining plant nutritional value, changes in timing of insect emergence, and fewer and saltier wetlands, foreshadow a decline in avian populations on the Great Plains. However, other possible effects such as increased drought resistance and water use efficiency of vegetation, longer growing seasons, and greater overall plant biomass promise at least some mitigation. Effects of multiple simultaneous perturbations such as can be expected under doubled carbon dioxide scenarios will require substantial basic research to clarify.

  12. Laser Atmospheric Transmitter Receiver-Network (LAnTeRN): A new approach for active measurement of atmospheric greenhouse gases

    Science.gov (United States)

    Dobler, J. T.; Braun, M.; Zaccheo, T.

    2012-12-01

    The Laser Atmospheric Transmitter Receiver-Network (LAnTeRN) is a new measurement concept that will enable local, regional and continental determination of key greenhouse gases, with unparalleled accuracy and precision. This new approach will offer the ability to make low bias, high precision, quasi-continuous, measurements to the accuracies required for separating anthropogenic and biogenic sources and sinks. In 2004 ITT Exelis developed an airborne demonstration unit, based on an intensity modulated continuous wave (IM-CW) lidar approach, for actively measuring atmospheric CO2 and O2. The multi-functional fiber laser lidar (MFLL) system relies on low peak power, high reliability, and efficient telecom laser components to implement this unique measurement approach. While evaluating methods for discriminating against thin clouds for the MFLL instrument, a new measurement concept was conceived. LAnTeRN has several fundamental characteristics in common with the MFLL instrument, but is a fundamentally different implementation and capability. The key difference is that LAnTeRN operates in transmission rather than in the traditional backscatter lidar configuration, which has several distinct advantages. Operating as a forward scatter, bistatic lidar system, LAnTeRN enables consideration of continuous monitoring from a geostationary orbit to multiple locations on the ground. Having the receivers on the ground significantly lowers cost and risk compared to an all space based mission, and allows the transmitter subsystem to be implemented, near term, as a hosted payload. Furthermore, the LAnTeRN measurement approach is also applicable for ground to ground measurements where high precision measurements over a long open path is required, such as facilities monitoring, or monitoring of passive volcanoes and fault lines. Using narrow linewidth laser sources allows flexibility to select the position on the absorption feature being probed. This feature allows for weighting the

  13. Global Warming: Understanding and Teaching the Forecast. Part A The Greenhouse Effect.

    Science.gov (United States)

    Andrews, Bill

    1993-01-01

    Provides information necessary for an interdisciplinary analysis of the greenhouse effect, enhanced greenhouse effect, global warming, global climate change, greenhouse gases, carbon dioxide, and scientific study of global warming for students grades 4-12. Several activity ideas accompany the information. (LZ)

  14. A New Perspective of the Physical Processes Associated with the Clear-Sky Greenhouse Effect over High Latitudes

    Institute of Scientific and Technical Information of China (English)

    Zuohao CAO; Ronald E.STEWART; M.K.YAU

    2004-01-01

    The physical processes associated with the clear-sky greenhouse effect in the presence of water vapor are examined by including surface emissivity in the greenhouse effect formulation, and by introducing a new way to partition physical processes of the greenhouse effect. In this new framework, it is found that the clear-sky greenhouse effect is governed by three physical processes associated with (1) the temperature contrast between the surface and the atmosphere, (2) the interaction between the surface emissivity and the temperature contrast, and (3) the surface emissivity. The importance of the three physical processes is assessed by computing their vertical and spectral variations for the subarctic winter and summer standard atmosphere using the radiation model MODTRAN3 (Moderate Resolution Transmittance code Version 3). The results show that the process associated with the temperature contrast between the surface and the atmosphere dominates over the other two processes in magnitude. The magnitude of this process has substantial variations in the spectral region of 1250 to 1880 cm-1 and in the far infrared region. Due to the low-level temperature inversion over the subarctic winter, there exists a negative contribution to the greenhouse trapping. The seasonal variations are, however, dominated by the processes associated with the interaction between the surface emissivity and the temperature contrast as well as the surface emissivity itself. The magnitudes of these two physical processes contributing to the greenhouse trapping over the subarctic winter are about 7 to 10 times of those over the subarctic summer, whereas the magnitude of the processes associated with the temperature contrast in the subarctic summer is only about 2 times of that in the subarctic winter.

  15. Estimating greenhouse gas emissions at the soil-atmosphere interface in forested watersheds of the US Northeast.

    Science.gov (United States)

    Gomez, Joshua; Vidon, Philippe; Gross, Jordan; Beier, Colin; Caputo, Jesse; Mitchell, Myron

    2016-05-01

    Although anthropogenic emissions of greenhouse gases (GHG: CO2, CH4, N2O) are unequivocally tied to climate change, natural systems such as forests have the potential to affect GHG concentration in the atmosphere. Our study reports GHG emissions as CO2, CH4, N2O, and CO2eq fluxes across a range of landscape hydrogeomorphic classes (wetlands, riparian areas, lower hillslopes, upper hillslopes) in a forested watershed of the Northeastern USA and assesses the usability of the topographic wetness index (TWI) as a tool to identify distinct landscape geomorphic classes to aid in the development of GHG budgets at the soil atmosphere interface at the watershed scale. Wetlands were hot spots of GHG production (in CO2eq) in the landscape owing to large CH4 emission. However, on an areal basis, the lower hillslope class had the greatest influence on the net watershed CO2eq efflux, mainly because it encompassed the largest proportion of the study watershed (54 %) and had high CO2 fluxes relative to other land classes. On an annual basis, summer, fall, winter, and spring accounted for 40, 27, 9, and 24 % of total CO2eq emissions, respectively. When compared to other approaches (e.g., random or systematic sampling design), the TWI landscape classification method was successful in identifying dominant landscape hydrogeomorphic classes and offered the possibility of systematically accounting for small areas of the watershed (e.g., wetlands) that have a disproportionate effect on total GHG emissions. Overall, results indicate that soil CO2eq efflux in the Archer Creek Watershed may exceed C uptake by live trees under current conditions.

  16. The combined effects of cover design parameters on tomato production of a passive greenhouse

    NARCIS (Netherlands)

    Vanthoor, B.H.E.; Stanghellini, C.; Henten, van E.; Gazquez, J.C.

    2008-01-01

    The objective of this paper is to demonstrate the need of a multiple design parameter approach to greenhouse design. To illustrate this need, we determined the combined effects of cover design parameters on tomato production of a passive greenhouse, that is a greenhouse with only natural ventilation

  17. The role of atmospheric greenhouse gases, orbital parameters, and southern ocean gateways: an idealized model study

    CERN Document Server

    Hertwig, Eileen; Fraedrich, Klaus

    2016-01-01

    A set of idealized experiments are performed to analyze the competing effects of declining atmospheric CO2 concentrations, the opening of an ocean gateway, and varying orbital parameters. These forcing mechanisms, which influence the global mean climate state, may have played a role for triggering climate transitions of the past (for example during the Eocene-Oligocene climate transition and the build-up of the Antarctic Ice Sheet). Sensitivity simulations with a coupled atmosphere-ocean general circulation model are conducted to test these three forcings and their roles for the global climate. The simulations are carried out under idealized conditions to focus on the essentials. The combination of all three forcings triggers a climate transition which resembles the onset of the Antarctic glaciation. In particular, the temperatures in the southern high latitudes decrease and snow accumulates constantly. Moreover, the relative importance of each possible forcing is explored. All three of the mechanisms (atmosp...

  18. [Errors Analysis and Correction in Atmospheric Methane Retrieval Based on Greenhouse Gases Observing Satellite Data].

    Science.gov (United States)

    Bu, Ting-ting; Wang, Xian-hua; Ye, Han-han; Jiang, Xin-hua

    2016-01-01

    High precision retrieval of atmospheric CH4 is influenced by a variety of factors. The uncertainties of ground properties and atmospheric conditions are important factors, such as surface reflectance, temperature profile, humidity profile and pressure profile. Surface reflectance is affected by many factors so that it is difficult to get the precise value. The uncertainty of surface reflectance will cause large error to retrieval result. The uncertainties of temperature profile, humidity profile and pressure profile are also important sources of retrieval error and they will cause unavoidable systematic error. This error is hard to eliminate only using CH4 band. In this paper, ratio spectrometry method and CO2 band correction method are proposed to reduce the error caused by these factors. Ratio spectrometry method can decrease the effect of surface reflectance in CH4 retrieval by converting absolute radiance spectrometry into ratio spectrometry. CO2 band correction method converts column amounts of CH4 into column averaged mixing ratio by using CO2 1.61 μm band and it can correct the systematic error caused by temperature profile, humidity profile and pressure profile. The combination of these two correction methods will decrease the effect caused by surface reflectance, temperature profile, humidity profile and pressure profile at the same time and reduce the retrieval error. GOSAT data were used to retrieve atmospheric CH4 to test and validate the two correction methods. The results showed that CH4 column averaged mixing ratio retrieved after correction was close to GOSAT Level2 product and the retrieval precision was up to -0.24%. The studies suggest that the error of CH4 retrieval caused by the uncertainties of ground properties and atmospheric conditions can be significantly reduced and the retrieval precision can be highly improved by using ratio spectrometry method and CO2 hand correction method.

  19. A space parasol as a countermeasure against the greenhouse effect

    Science.gov (United States)

    Hudson, H. S.

    1991-01-01

    It is suggested that the deployment of a 'space parasol' at the L1 Langrangian point of the earth-sun system would serve to intercept some desired fraction of the solar radiant energy, thereby lessening the impact of the greenhouse effect. The parasol satellites are described and possible orbit configurations are discussed. Orbital possibilities include Low Earth Orbit, Geosynchronous orbit, and L1 which appears to be the best option. Structural strength, control, and use of extraterrestrial material in the construction of the parasol are discussed.

  20. PRUNING SYSTEM EFFECT ON GREENHOUSE GRAFTED TOMATO YIELD AND QUALITY

    OpenAIRE

    Mourão, Isabel; Teixeira, Joana; Brito, L Miguel; Ferreira, Maria Elvira; Moura, Maria Luisa

    2014-01-01

    This study aimed to evaluate the effects on tomato yield and quality of three pruning systems (2, 3 and 4 stems) of grafted plants (cv. Vinicio and Multifort) used to prevent the incidence of soil diseases. It was also investigated if the two stems from nodes of the cotyledon leaves improved crop performance compared to the two stems from the first true leaves nodes. The experiment was conducted in the spring/summer season, under greenhouse conditions at NW Portugal, with a randomized block d...

  1. The Effect of Taxation on Greenhouse Gas Emissions

    Directory of Open Access Journals (Sweden)

    Žiga KOTNIK

    2014-10-01

    Full Text Available This paper examines the effect of governmental environmental taxes on greenhouse gas (GHG emissions using a panel data set of 19 EU countries for the time period 1995-2010. We estimate both direct and indirect effects of governmental environmental taxes on GHG emissions in industrial processes. The indirect effect in particular operates through the effect of environmental expenditure for reduction of GHG emissions in industry. To take into account the dynamic nature and to properly address the potential endogeneity, adequate econometric methods are applied. We have shown that the direct effect of environmental taxes on GHG emissions is negative, while the indirect effect through environmental expenditures is also negative and even more statistically significant. Consequently, some policy implications may be derived from the results.

  2. The Effect of Taxation on Greenhouse Gas Emissions

    Directory of Open Access Journals (Sweden)

    Žiga KOTNIK

    2014-11-01

    Full Text Available This paper examines the effect of governmental environmental taxes on greenhouse gas (GHG emissions using a panel data set of 19 EU countries for the time period 1995-2010. We estimate both direct and indirect effects of governmental environmental taxes on GHG emissions in industrial processes. The indirect effect in particular operates through the effect of environmental expenditure for reduction of GHG emissions in industry. To take into account the dynamic nature and to properly address the potential endogeneity, adequate econometric methods are applied. We have shown that the direct effect of environmental taxes on GHG emissions is negative, while the indirect effect through environmental expenditures is also negative and even more statistically significant. Consequently, some policy implications may be derived from the results.

  3. The effect of low ancient greenhouse climate temperature gradients on the ocean's overturning circulation

    Directory of Open Access Journals (Sweden)

    W. P. Sijp

    2015-10-01

    Full Text Available We examine whether the reduced meridional temperature gradients of past greenhouse climates might have reduced oceanic overturning, leading to a more quiescent subsurface ocean. A substantial reduction of the pole to equator temperature difference is achieved in a coupled climate model via an altered radiative balance in the atmosphere. Contrary to expectations, we find that the meridional overturning circulation and deep ocean kinetic energy remain relatively unaffected. Reducing the wind strength also has remarkably little effect on the overturning. Instead, overturning strength depends on deep ocean density gradients, which remain relatively unaffected by the surface changes, despite an overall decrease in ocean density. Ocean poleward heat transport is significantly reduced only in the Northern Hemisphere, as now the circulation operates across a reduced temperature gradient, suggesting the overturning circulation dominates heat transport in greenhouse climates. These results indicate that climate models of the greenhouse climate during the Cretaceous and early Paleogene may yield a reasonable overturning circulation, despite failing to fully reproduce the extremely reduced temperature gradients of those time periods.

  4. [Preliminary assessment of the potential of biochar technology in mitigating the greenhouse effect in China].

    Science.gov (United States)

    Jiang, Zhi-Xiang; Zheng, Hao; Li, Feng-Min; Wang, Zhen-Yu

    2013-06-01

    The production of biochar by pyrolysis and its application to soil can sequester the CO2 which was absorbed by plants from atmosphere into soil, in addition it can also bring multiple benefits for agriculture production. On the basis of the available potential survey of the biomass residues from agriculture and forestry section, life cycle assessment was employed to quantify the potential of biochar technology in mitigation of greenhouse gases in our country. The results showed: In China, the amount of available biomass resource was 6.04 x 10(8) t every year and its net greenhouse effect potential was 5.32 x 10(8) t CO(2e) (CO(2e): CO2 equivalent), which was equivalent to 0.88 t CO(2e) for every ton biomass. The greatest of contributor to the total potential was plant carbon sequestration in soil as the form of biochar which accounts for 73.94%, followed by production of renewable energy and its percentage was 23.85%. In summary, production of biochar from agriculture and forestry biomass residues had a significant potential for our country to struggle with the pressure of greenhouse gas emission.

  5. Knowledge about the 'Greenhouse Effect': have college students improved?

    Science.gov (United States)

    Jeffries, Helen; Stanisstreet, Martin; Boyes, Edward

    2001-02-01

    The prevalence of the ideas of Year I undergraduate biology students about the consequences, causes and cures of the 'greenhouse effect' was determined using a closed-form questionnaire, and the results compared with a parallel study undertaken nearly 10 years ago. Many of the students in the present study were unaware of the potential effect of global warming on the distribution of crop pests, or that ground level ozone acts as a 'greenhouse gas'. Prevalent misconceptions were that global warming is caused by increased penetration of solar radiation, that it is connected with holes in the ozone layer, that it would result in increased skin cancer, and that use of unleaded petrol would reduce it. There appeared to be a general conflation of thinking about global warming and ozone layer depletion. Despite an increased certainty about the existence and effects of global warming among experts, the results are broadly similar to, and certainly no better than, those obtained with an equivalent group of students in a previous study, suggesting that despite media publicity and inclusion of the issue of global warming in the formal curriculum, insecure knowledge and misconceptions persist.

  6. Comparison of the observed and calculated clear sky greenhouse effect - Implications for climate studies

    Science.gov (United States)

    Kiehl, J. T.; Briegleb, B. P.

    1992-01-01

    The clear sky greenhouse effect is defined in terms of the outgoing longwave clear sky flux at the top of the atmosphere. Recently, interest in the magnitude of the clear sky greenhouse effect has increased due to the archiving of the clear sky flux quantity through the Earth Radiation Budget Experiment (ERBE). The present study investigates to what degree of accuracy this flux can be analyzed by using independent atmospheric and surface data in conjunction with a detailed longwave radiation model. The conclusion from this comparison is that for most regions over oceans the analyzed fluxes agree to within the accuracy of the ERBE-retrieved fluxes (+/- 5 W/sq m). However, in regions where deep convective activity occurs, the ERBE fluxes are significantly higher (10-15 W/sq m) than the calculated fluxes. This bias can arise from either cloud contamination problems or variability in water vapor amount. It is argued that the use of analyzed fluxes may provide a more consistent clear sky flux data set for general circulation modeling validation. Climate implications from the analyzed fluxes are explored. Finally, results for obtaining longwave surface fluxes over the oceans are presented.

  7. Atmospheric observations for quantifying emissions of point-source synthetic greenhouse gases (CF4, NF3 and HFC-23)

    Science.gov (United States)

    Arnold, Tim; Manning, Alistair J.; Li, Shanlan; Kim, Jooil; Park, Sunyoung; Fraser, Paul J.; Mitrevski, Blagoj; Steele, L. Paul; Krummel, Paul B.; Mühle, Jens; Weiss, Ray F.

    2016-04-01

    The fluorinated species carbon tetrafluoride (CF4; PFC-14), nitrogen trifluoride (NF3) and trifluoromethane (CHF3; HFC-23) are potent greenhouse gases with 100-year global warming potentials of 6,630, 16,100 and 12,400, respectively. Unlike the majority of CFC-replacement compounds that are emitted from fugitive and mobile emission sources, these gases are largely emitted from large single point sources - semiconductor manufacturing facilities (all three), aluminium smelting plants (CF4) and chlorodifluoromethane factories (HFC-23). In this work we show the potential for atmospheric measurements to understand regional sources of these gases and to highlight emission 'hotspots'. We target our analysis on measurements from two Advanced Global Atmospheric Gases Experiment (AGAGE) long term monitoring sites that are particularly sensitive to regional emissions of these gases: Gosan on Jeju Island in the Republic of Korea and Cape Grim on Tasmania in Australia. These sites measure CF4, NF3 and HFC-23 alongside a suite of greenhouse and stratospheric ozone depleting gases every two hours using automated in situ gas-chromatography mass-spectrometry instrumentation. We couple each measurement to an analysis of air history using the regional atmospheric transport model NAME (Numerical Atmospheric dispersion Modelling Environment) driven by 3D meteorology from the Met Office's Unified Model, and use a Bayesian inverse method (InTEM - Inversion Technique for Emission Modelling) to calculate yearly emission changes over a decade (2005-2015) at high spatial resolution. At present these gases make a small contribution to global radiative forcing, however, given that their impact could rise significantly and that point sources of such gases can be mitigated, atmospheric monitoring could be an important tool for aiding emissions reduction policy.

  8. The effect of floating vegetation on denitrification and greenhouse gas production in wetland mesocosms

    Science.gov (United States)

    Jacobs, A. E.; Harrison, J. A.

    2012-12-01

    Anthropogenic intensification of nitrogen (N) loading to aquatic ecosystems is widespread and can lead to the degradation of these systems. Wetlands are important sites for N removal via denitrification, the microbially mediated reduction of reactive nitrate to inert N2 gas, but they can also produce high levels of greenhouse gases. Floating plants play an important role in encouraging denitrification, since they create low oxygen conditions that may favor denitrification. We investigated whether wetland sediments with floating plant cover had higher denitrification and greenhouse gas production rates than wetland sediments without floating plants. Replicate flow-through mesocosms with wetland sediment and water were constructed in a growth chamber to mimic the wetland where the sediment and water were collected. Mesocosm treatments were covered with floating vegetation (duckweed), an opaque tarp, or no cover to determine how cover type affects denitrification and greenhouse gas production and whether biotic or abiotic factors are likely responsible for observed differences. Denitrification and greenhouse gas production rates were calculated by measuring excess N2 gas, methane, and nitrous oxide concentrations in the water column and measuring the gas exchange rates between the water column and the atmosphere. Gas exchange rates were measured using an inert volatile tracer added to the water column and accumulation of gas in the mesocosm headspace. Additional mesocosm experiments were performed to determine how duckweed-dominated wetland systems respond to nitrogen loading and which mechanism for lowering dissolved oxygen concentrations is important in affecting denitrification under floating vegetation. Mesocosms with floating vegetation had lower dissolved oxygen than no cover or tarp-covered mesocosms, which is consistent with field and literature observations. Water flowing out of the mesocosms had statistically lower total nitrogen and nitrate concentrations

  9. Climate-chemical interactions and greenhouse effects of trace gases

    Science.gov (United States)

    Shi, Guang-Yu; Fan, Xiao-Biao

    1994-01-01

    A completely coupled one-dimensional radiative-convective (RC) and photochemical-diffusion (PC) model has been developed recently and used to study the climate-chemical interactions. The importance of radiative-chemical interactions within the troposphere and stratosphere has been examined in some detail. We find that increases of radiatively and/or chemically active trace gases such as CO2, CH4 and N2O have both the direct effects and the indirect effects on climate change by changing the atmospheric O3 profile through their interaction with chemical processes in the atmosphere. It is also found that the climatic effect of ozone depends strongly on its vertical distribution throughout the troposphere and stratosphere, as well on its column amount in the atmosphere.

  10. Solar energy: the physics of the greenhouse effect.

    Science.gov (United States)

    Young, M

    1975-07-01

    For practical reasons, it is likely that low-temperature solar collectors have a more immediate future than high-temperature or photovoltaic generation of electricity. This paper discusses the physics of bare and covered flat-plate collectors. The greenhouse effect is the result of reducing convection to the point that radiation trapping becomes important. Nevertheless, at collector temperatures within 20-30 degrees C of ambient, convection from the collector surface is so important that a special absorber with low ir emissivity may be no more efficient than a good, black absorber. At higher temperatures, selective absorbers are desirable. In the low temperature range, collection efficiency can be kept well over 80%, but falls rapidly with increasing collector temperature. This suggests that solar power may see early application in conjunction with heat pumps for heating and air conditioning.

  11. Using Interactive Technology to Support Students' Understanding of the Greenhouse Effect and Global Warming

    Science.gov (United States)

    Varma, Keisha; Linn, Marcia C.

    2012-01-01

    In this work, we examine middle school students' understanding of the greenhouse effect and global warming. We designed and refined a technology-enhanced curriculum module called "Global Warming: Virtual Earth". In the module activities, students conduct virtual experiments with a visualization of the greenhouse effect. They analyze data and draw…

  12. "Home Made" Model to Study the Greenhouse Effect and Global Warming

    Science.gov (United States)

    Onorato, P.; Mascheretti, P.; DeAmbrosis, A.

    2011-01-01

    In this paper a simplified two-parameter model of the greenhouse effect on the Earth is developed, starting from the well known two-layer model. It allows both the analysis of the temperatures of the inner planets, by focusing on the role of the greenhouse effect, and a comparison between the temperatures the planets should have in the absence of…

  13. Rich soil carbon and nitrogen but low atmospheric greenhouse gas fluxes from North Sulawesi mangrove swamps in Indonesia.

    Science.gov (United States)

    Chen, Guang C; Ulumuddin, Yaya I; Pramudji, Sastro; Chen, Shun Y; Chen, Bin; Ye, Yong; Ou, Dan Y; Ma, Zhi Y; Huang, Hao; Wang, Jing K

    2014-07-15

    The soil to atmosphere fluxes of greenhouse gases N2O, CH4 and CO2 and their relationships with soil characteristics were investigated in three tropical oceanic mangrove swamps (Teremaal, Likupang and Kema) in North Sulawesi, Indonesia. Mangrove soils in North Sulawesi were rich in organic carbon and nitrogen, but the greenhouse gas fluxes were low in these mangroves. The fluxes ranged -6.05-13.14 μmol m(-2)h(-1), -0.35-0.61 μmol m(-2)h(-1) and -1.34-3.88 mmol m(-2)h(-1) for N2O, CH4 and CO2, respectively. The differences in both N2O and CH4 fluxes among different mangrove swamps and among tidal positions in each mangrove swamp were insignificant. CO2 flux was influenced only by mangrove swamps and the value was higher in Kema mangrove. None of the measured soil parameters could explain the variation of CH4 fluxes among the sampling plots. N2O flux was negatively related to porewater salinity, while CO2 flux was negatively correlated with water content and organic carbon. This study suggested that the low gas emissions due to slow metabolisms would lead to the accumulations of organic matters in North Sulawesi mangrove swamps.

  14. A new index to assess chemicals increasing the greenhouse effect based on their toxicity to algae.

    Science.gov (United States)

    Wang, Ting; Zhang, Xiaoxian; Tian, Dayong; Gao, Ya; Lin, Zhifen; Liu, Ying; Kong, Lingyun

    2015-11-01

    CO2, as the typical greenhouse gas causing the greenhouse effect, is a major global environmental problem and has attracted increasing attention from governments. Using algae to eliminate CO2, which has been proposed as an effective way to reduce the greenhouse effect in the past decades, can be disturbed by a growing number of artificial chemicals. Thus, seven types of chemicals and Selenastrum capricornutum (algae) were examined in this study, and the good consistency between the toxicity of artificial chemicals to algae and the disturbance of carbon fixation by the chemicals was revealed. This consistency showed that the disturbance of an increasing number of artificial chemicals to the carbon fixation of algae might be a "malware" worsening the global greenhouse effect. Therefore, this study proposes an original, promising index to assess the risk of deepening the greenhouse effect by artificial chemicals before they are produced and marketed.

  15. WMO WDCGG data report. GAW data. Volume IV - greenhouse gases and other atmospheric gases. WDCGG No. 25

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    The report contains data on the concentrations of greenhouse gases and related gases in the atmosphere and the oceans. This report contains monthly and annual mean values collected from January 1998 to October 2000 on global, regional and local scales, together with information on observation stations. Gases include: carbon dioxide, methane, nitrous oxide, carbon monoxide, nitrogen dioxide, nitrogen monoxide, sulphur dioxide, chlorofluorocarbons, tetrachloroethane, trichloroethane and trichloromethane. Trends in concentrations and growth rates presented mainly in graphical form for observation stations around the world. Tables list concentrations of gases, over periods covered at all reporting stations with average growth rates per year and also regression equations of trends. Geographical locations of observation stations are also listed.

  16. WMO WDCGG data catalogue. GAW data. Volume IV - Greenhouse gases and other atmospheric gases

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    The fourth issue of the data catalogue gives information on measurement methods, instruments, and data handling procedures for recording data on greenhouse gases at the observation stations submitting data to the WDCGG up to December 2000. Chapter 1 gives details of the observation stations; Chapter 2, the data index, is prepared to give notice of the data. Chapter 3 contains detail of the observation programme: category and location, date when observation started, instrument manufacturers, characteristics of instrument system calibration methods, and data selection procedures. It gives references on the observation programme at each station. Gases measured are: carbon dioxide, methane, nitrous oxide, chlorofluorocarbons, hydrochlorofluorocarbons, hydrofluorocarbons, tetrachloromethane, trichloroethane, trichloromethane, carbon monoxide, nitrogen monoxide, nitrogen oxides, odd nitrogen, nitrogen dioxide, sulphur dioxide, volatile organic compounds (VOCs), organic peroxides, hydrogen peroxide, and isotopes ({sup 13}C). 3 apps.

  17. A Cloud Greenhouse Effect on Mars: Significant Climate Change in the Recent Past

    Science.gov (United States)

    Haberle, Robert M.; Kahre, Melinda A.; Schaeffer, James R.; Montmessin, Frank; Phillips, R J.

    2012-01-01

    The large variations in Mars orbit parameters are known to be significant drivers of climate change on the Red planet. The recent discovery of buried CO2 ice at the South Pole adds another dimension to climate change studies. In this paper we present results from the Ames GCM that show within the past million years it is possible that clouds from a greatly intensified Martian hydrological cycle may have produced a greenhouse effect strong enough to raise global mean surface temperatures by several tens of degrees Kelvin. It is made possible by the ability of the Martian atmosphere to transport water to high altitudes where cold clouds form, reduce the outgoing longwave radiation, and drive up surface temperatures to maintain global energy balance.

  18. The Impact of Upper Tropospheric Humidity from Microwave Limb Sounder on the Midlatitude Greenhouse Effect

    Science.gov (United States)

    Hu, Hua; Liu, W. Timothy

    1998-01-01

    This paper presents an analysis of upper tropospheric humidity, as measured by the Microwave Limb Sounder, and the impact of the humidity on the greenhouse effect in the midlatitudes. Enhanced upper tropospheric humidity and an enhanced greenhouse effect occur over the storm tracks in the North Pacific and North Atlantic. In these areas, strong baroclinic activity and the large number of deep convective clouds transport more water vapor to the upper troposphere, and hence increase greenhouse trapping. The greenhouse effect increases with upper tropospheric humidity in areas with a moist upper troposphere (such as areas over storm tracks), but it is not sensitive to changes in upper tropospheric humidity in regions with a dry upper troposphere, clearly demonstrating that there are different mechanisms controlling the geographical distribution of the greenhouse effect in the midlatitudes.

  19. The Impact of Secondary School Students' Preconceptions on the Evolution of Their Mental Models of the Greenhouse Effect and Global Warming

    Science.gov (United States)

    Reinfried, Sibylle; Tempelmann, Sebastian

    2014-01-01

    This paper provides a video-based learning process study that investigates the kinds of mental models of the atmospheric greenhouse effect 13-year-old learners have and how these mental models change with a learning environment, which is optimised in regard to instructional psychology. The objective of this explorative study was to observe and…

  20. The Impact of Secondary School Students' Preconceptions on the Evolution of Their Mental Models of the Greenhouse Effect and Global Warming

    Science.gov (United States)

    Reinfried, Sibylle; Tempelmann, Sebastian

    2014-01-01

    This paper provides a video-based learning process study that investigates the kinds of mental models of the atmospheric greenhouse effect 13-year-old learners have and how these mental models change with a learning environment, which is optimised in regard to instructional psychology. The objective of this explorative study was to observe and…

  1. A Three-Tier Diagnostic Test to Assess Pre-Service Teachers' Misconceptions about Global Warming, Greenhouse Effect, Ozone Layer Depletion, and Acid Rain

    Science.gov (United States)

    Arslan, Harika Ozge; Cigdemoglu, Ceyhan; Moseley, Christine

    2012-01-01

    This study describes the development and validation of a three-tier multiple-choice diagnostic test, the atmosphere-related environmental problems diagnostic test (AREPDiT), to reveal common misconceptions of global warming (GW), greenhouse effect (GE), ozone layer depletion (OLD), and acid rain (AR). The development of a two-tier diagnostic test…

  2. Improved Estimates of Clear Sky Longwave Flux and Application to the Tropical Greenhouse Effect

    Science.gov (United States)

    Collins, W. D.

    1997-01-01

    The first objective of this investigation is to eliminate the clear-sky offset introduced by the scene-identification procedures developed for the Earth Radiation Budget Experiment (ERBE). Estimates of this systematic bias range from 10 to as high as 30 W/sq m. The initial version of the ScaRaB data is being processed with the original ERBE algorithm. Since the ERBE procedure for scene identification is based upon zonal flux averages, clear scenes with longwave emission well below the zonal mean value are mistakenly classified as cloudy. The erroneous classification is more frequent in regions with deep convection and enhanced mid- and upper-tropospheric humidity. We will develop scene identification parameters with zonal and/or time dependence to reduce or eliminate the bias in the clear- sky data. The modified scene identification procedure could be used for the ScaRaB-specific version of the Earth-radiation products. The second objective is to investigate changes in the clear-sky Outgoing Longwave Radiation (OLR) associated with decadal variations in the tropical and subtropical climate. There is considerable evidence for a shift in the climate state starting in approximately 1977. The shift is accompanied by higher SSTs in the equatorial Pacific, increased tropical convection, and higher values of atmospheric humidity. Other evidence indicates that the humidity in the tropical troposphere has been steadily increasing over the last 30 years. It is not known whether the atmospheric greenhouse effect has increased during this period in response to these changes in SST and precipitable water. We will investigate the decadal-scale fluctuations in the greenhouse effect using Nimbus-7, ERBE, and ScaRaB measurements spaning 1979 to the present. The data from the different satellites will be intercalibrated by comparison with model calculations based upon ship radiosonde observations. The fluxes calculated from the radiation model will also be used for validation of the

  3. The social representations of the greenhouse effect; Les representations sociales de l'effet de serre

    Energy Technology Data Exchange (ETDEWEB)

    Boy, D.

    2000-07-01

    This document presents the results analysis to the inquiry realized during may and june 2000 on the greenhouse effect perception by the public. The following questions have been asked and analyzed: what is the greenhouse effect, who is responsible of the greenhouse effect, what will be the consequences of the greenhouse effect, how to meet with this effect, information and perception. (A.L.B.)

  4. The effect of agricultural trade liberalisation on land-use related greenhouse gas emissions

    NARCIS (Netherlands)

    Verburg, R.W.; Stehfest, E.; Woltjer, G.B.; Eickhout, B.

    2009-01-01

    This study explores the effects of agricultural trade liberalisation and concomitant changes in agricultural areas and livestock production on greenhouse gas emissions using the coupled LEITAP–IMAGE modelling system. The results indicate that liberalisation leads to an increase in total greenhouse g

  5. Cost-effectiveness of greenhouse gas tax and CO2 tax

    NARCIS (Netherlands)

    Kerkhof, A.C.; Moll, H.C.; Drissen, E.; Wilting, H.C.

    2006-01-01

    Current economic instruments aimed at mitigating climate change focus on CO2 emissions, but the Kyoto Protocol refers to six greenhouse gases (CO2, CH4, N2O, HFCs, PFCs and SF6). Inclusion of non-CO2 greenhouse gases in economic instruments can increase the cost-effectiveness of achieving the Kyoto

  6. The climatic warming up (the greenhouse effect); Le rechauffement climatique (l'effet de serre)

    Energy Technology Data Exchange (ETDEWEB)

    Jancovici, J.M.; Jouzel, J. [CEA Saclay, Lab. des Sciences du Climat et de l' Environnement, 91 - Gif-sur-Yvette (France); Lorius, C. [Centre National de la Recherche Scientifique (CNRS), Lab. de Glaciologie et Geophysique de l' Environnement, 38 - Grenoble (France)] [and others

    2000-05-01

    Facing the environmental and biological impacts of the climatic warming up, scientists and economists organized a debate on the subject. After a theoretical presentation of the greenhouse effect and the greenhouse gases, the climatic changes are discussed and simulation of the effects are presented. The today effects and tomorrow impacts on the agriculture and the public health are also presented. A synthesis is proposed to discuss the contribution of the energy policy and of the technological progress in measures of greenhouse effect control. (A.L.B.)

  7. A Miniaturized Laser Heterodyne Radiometer for Greenhouse Gas Measurements in the Atmospheric Column

    Science.gov (United States)

    Steel, Emily Wilson

    2015-01-01

    Laser Heterodyne Radiometry is a technique adapted from radio receiver technology has been used to measure trace gases in the atmosphere since the 1960s.By leveraging advances in the telecommunications industry, it has been possible to miniaturize this technology.The mini-LHR (Miniaturized Laser Heterodyne Radiometer) has been under development at NASA Goddard Space flight Center since 2009. This sun-viewing instrument measures carbon dioxide and methane in the atmospheric column and operates in tandem with an AERONET sun photometer producing a simultaneous measure of aerosols. The mini-LHR has been extensively field tested in a range of locations ranging in the continental US as well as Alaska and Hawaii and now operates autonomously with sensitivities of approximately 0.2 ppmv and approximately10 ppbv, for carbon dioxide and methane respectively, for 10 averaged scans under clear sky conditions.

  8. Atmospheric greenhouse gases retrieved from SCIAMACHY: comparison to ground-based FTS measurements and model results

    Directory of Open Access Journals (Sweden)

    O. Schneising

    2012-02-01

    Full Text Available SCIAMACHY onboard ENVISAT (launched in 2002 enables the retrieval of global long-term column-averaged dry air mole fractions of the two most important anthropogenic greenhouse gases carbon dioxide and methane (denoted XCO2 and XCH4. In order to assess the quality of the greenhouse gas data obtained with the recently introduced v2 of the scientific retrieval algorithm WFM-DOAS, we present validations with ground-based Fourier Transform Spectrometer (FTS measurements and comparisons with model results at eight Total Carbon Column Observing Network (TCCON sites providing realistic error estimates of the satellite data. Such validation is a prerequisite to assess the suitability of data sets for their use in inverse modelling.

    It is shown that there are generally no significant differences between the carbon dioxide annual increases of SCIAMACHY and the assimilation system CarbonTracker (2.00 ± 0.16 ppm yr−1 compared to 1.94 ± 0.03 ppm yr−1 on global average. The XCO2 seasonal cycle amplitudes derived from SCIAMACHY are typically larger than those from TCCON which are in turn larger than those from CarbonTracker. The absolute values of the northern hemispheric TCCON seasonal cycle amplitudes are closer to SCIAMACHY than to CarbonTracker and the corresponding differences are not significant when compared with SCIAMACHY, whereas they can be significant for a subset of the analysed TCCON sites when compared with CarbonTracker. At Darwin we find discrepancies of the seasonal cycle derived from SCIAMACHY compared to the other data sets which can probably be ascribed to occurrences of undetected thin clouds. Based on the comparison with the reference data, we conclude that the carbon dioxide data set can be characterised by a regional relative precision (mean standard deviation of the differences of about 2.2 ppm and a relative accuracy (standard deviation of the mean differences

  9. Catchment-Wide Atmospheric Greenhouse Gas Exchange as Influenced by Land Use Diversity

    DEFF Research Database (Denmark)

    Herbst, Mathias; Friborg, Thomas; Ringgaard, Rasmus

    2011-01-01

    The turbulent fl uxes of carbon dioxide between the land surface and the atmosphere were measured with the eddy covariance technique above three contrasO ng land use types in the Skjern River catchment in western Denmark, namely an agricultural area, a forest plantation, and a wet grassland....... The measurements also included the turbulent fl uxes of methane above the wet grassland and of nitrous oxide above the agricultural area and ran continuously throughout the year 2009. The highest CO2 uptake rates (around 30 µmol m-2 s-1) were observed at the agricultural site; however, the site was a CO2 sink only...

  10. 温室效应对温室气体浓度变化的敏感性分析%Sensitivity Analysis of Greenhouse Effect With the Concentration Changes of Greenhouse Gases

    Institute of Scientific and Technical Information of China (English)

    胡金鹏; 崔国民; 黄晓璜; 华泽钊

    2012-01-01

    工业革命以来人类活动排放到大气中的主要温室气体有C02、CH4、N20等,其在大气中的含量增加引起吸收地表辐射能量的增加,改变了地表一大气辐射平衡,造成了地表温度升高。本文研究了温室气体含量增加同其吸收地表辐射能量的关系;比较了不同温室气体含量引起的吸收地表辐射能量变化的差异,提出了温室效应对不同温室气体浓度变化的敏感性的概念。通过对敏感性的分析,得出了不同温室气体含量的变化对温室效应影响的强弱关系。%Since the industrial revolution, the main greenhouse gases which human activities released into the atmosphere of are C02, CH4, N20, etc. It makes globe warming that the increasing abso- rption of terrestrial radiation caused by the changes of GHGs concentration changed the radiation balance between the surface and atmosphere. In this paper, we discussed the relationship between the increasing amounts of the GHGs in atmosphere and their Greenhouse effects. At the same time, we compared the variation of different GHG's Greenhouse effect and calculate every GHG's sensitivity to its concentration changes. Through the analysis of its sensitivity, combined with the annual growth rate of GHGs emissions, this paper made appropriate predictions on Greenhouse effect trends to different GHGs in the future.

  11. Calculation of NIR effect on greenhouse climate in various conditions

    NARCIS (Netherlands)

    Kempkes, F.L.K.; Hemming, S.

    2012-01-01

    In Northern regions of Europe glass is mainly used as greenhouse covering material whereas in Southern regions plastic films are commonly used. The develop-ment of covering material optical properties focuses on high light transmission, reduction of heating energy losses (higher latitudes) and reduc

  12. Soil Carbon Sequestration and the Greenhouse Effect (2nd Edition)

    Science.gov (United States)

    This volume is a second edition of the book “Soil Carbon Sequestration and The Greenhouse Effect”. The first edition was published in 2001 as SSSA Special Publ. #57. The present edition is an update of the concepts, processes, properties, practices and the supporting data. All chapters are new co...

  13. The role of forestry development in China in alleviating greenhouse effects

    Energy Technology Data Exchange (ETDEWEB)

    Liu Hong

    1996-12-31

    Forestry development in China has gained great achievements and made great progress in realizing sustainable forest management and alleviating global climate change. The main measures to mitigate greenhouse effects through the means of forestry development include afforestation to increase the forested area, fuel wood forest development, management improvement, wise utilization, international cooperation, investment increase, forest related scientific research, strengthening the forest law enforcement system. Climate change as well as how to alleviate the greenhouse effects is a hot topic at present. This paper describes the achievements of China`s forestry development and its role to alleviate the greenhouse effects, and puts forward the measures to mitigate greenhouse effects through the means of forestry development.

  14. Models of Students' Thinking Concerning the Greenhouse Effect and Teaching Implications.

    Science.gov (United States)

    Koulaidis, Vasilis; Christidou, Vasilia

    1999-01-01

    Primary school students (n=40) ages 11 and 12 years were interviewed concerning their conceptions of the greenhouse effect. Analysis of the data led to the formation of seven distinct models of thinking regarding this phenomenon. (Author/CCM)

  15. What Light through Yonder Window Breaks?--The Greenhouse Effect Revisited.

    Science.gov (United States)

    Bohren, Craig F.

    1992-01-01

    Presents three experiments exploring aspects of the greenhouse effect. Topics and discussion includes radiation in energy transfer, emissivity and absorptivity, the irrelevance of reflectivity, a digression on insulators and convection, climate change, and radiative energy balance. (MCO)

  16. Effect of the greenhouse gases (CO2, H2O, SO2) on Martian paleoclimate

    Science.gov (United States)

    Postawko, S. E.; Kuhn, W. R.

    1986-01-01

    There is general agreement that certain surface features on Mars are indicative of the presence of liquid water at various times in the geologic past. In particular, the valley networks are difficult to explain by a mechanism other than the flow of liquid water. It has been suggested in several studies that a thick CO2 atmosphere on Mars early in its history could have provided a greenhouse warming that would have allowed the flow of water either on the surface or just below the surface. However, this effect was examined with a detailed radiation model, and it was found that if reduced solar luminosity early in the history of the solar system is taken into account, even three bars of CO2 will not provide sufficient greeenhouse warming. The addition of water vapor and sulflur dioxide (both plausible gases that may have been emitted by Martian volcanoes) to the atmosphere also fail to warm the surface above 273 K for reduced solar luminosity conditions. The increase in temperature may be large enough, however, for the formation of these features by brines.

  17. Greenhouse Warming Research

    DEFF Research Database (Denmark)

    Sørensen, Bent Erik

    2016-01-01

    The changing greenhouse effect caused by natural and anthropogenic causes is explained and efforts to model the behavior of the near-surface constituents of the Earth's land, ocean and atmosphere are discussed. Emissions of various substances and other aspects of human activity influence the gree......The changing greenhouse effect caused by natural and anthropogenic causes is explained and efforts to model the behavior of the near-surface constituents of the Earth's land, ocean and atmosphere are discussed. Emissions of various substances and other aspects of human activity influence...... the greenhouse warming, and the impacts of the warming may again impact the wellbeing of human societies. Thus physical modeling of the near-surface ocean-soil-atmosphere system cannot be carried out without an idea of the development of human activities, which is done by scenario analysis. The interactive...... nature of the natural and the human system calls for an extremely complex analysis, in order to predict the outcome of various proposed changes in human behavior. This includes halting activities that most influence the climate and finding workable alternatives to these activities, or adapting to climate...

  18. Lay perceptions of the greenhouse effect; Les representations profanes de l'effet de serre

    Energy Technology Data Exchange (ETDEWEB)

    Peretti-Watel, P. [Institut National de la Sante et de la Recherche Medicale (INSERM), UMR 379, Epidemiologie et Sciences Sociales Appliquees a l' Innovation Medicale / ORS PACA, 13 - Marseille (France); Hammer, B. [Electricite de France (EDF-GRETS), 92 - Clamart (France)

    2006-10-15

    Using the data from the French Environment Barometer EDF-RD 2004 (national representative sample of French citizens aged over 15) and surveys by ADEME between 2000 and 2005, the paper investigates lay perceptions of the causes and consequences of the greenhouse effect, which may be considered as archetypical of contemporary environmental risks. Beyond lay lack of knowledge, the greenhouse effect gives rise to coherent and meaningful cognitions, including causal explanations, shaped by the pre-existing cognitive framework. This cognitive work, based on analogic rather than scientific thought, strings together the greenhouse effect, ozone depletion, air pollution and even nuclear power. The cognitive process is also fed by the individuals' general conceptions of Nature and of the rights and duties of humankind towards Nature. People are not greatly worried about the unseen and controversial consequences of the greenhouse effect: such worry could be one of those 'elite fears' mentioned by Beck. Finally, while the efficiency of public policies to counter the greenhouse effect requires extensive societal involvement, low confidence towards both political and scientific authorities may prevent the population from becoming aware of the environmental stakes tied to the greenhouse effect. (authors)

  19. Effectiveness of horizontal air flow fans supporting natural ventilation in a Mediterranean multi-span greenhouse

    Directory of Open Access Journals (Sweden)

    Alejandro López

    2013-08-01

    Full Text Available Natural ventilation is the most important method of climate control in Mediterranean greenhouses. In this study, the microclimate and air flow inside a Mediterranean greenhouse were evaluated by means of sonic anemometry. Experiments were carried out in conditions of moderate wind (≈ 4.0 m s-1, and at low wind speed (≈ 1.8 m s-1 the natural ventilation of the greenhouse was supplemented by two horizontal air flow fans. The greenhouse is equipped with a single roof vent opening to the windward side and two side vents, the windward one being blocked by another greenhouse close to it, while the leeward one is free of obstacles. When no fans are used, air enters through the roof vent and exits through both side vents, thus flowing contrary to the thermal effect which causes hot air to rise and impairing the natural ventilation of the greenhouse. Using fans inside the greenhouse helps the air to circulate and mix, giving rise to a more homogeneous inside temperature and increasing the average value of normalized air velocity by 365 %. These fans also increase the average values of kinetic turbulence energy inside the greenhouse by 550 % compared to conditions of natural ventilation. As the fans are placed 4 m away from the side vents, their effect on the entrance of outside air is insufficient and they do not help to reduce the inside temperature on hot days with little wind. It is therefore recommended to place the fans closer to the side vents to allow an additional increase of the air exchange rate of greenhouses.

  20. [Effects of sunken depth of energy-saving solar greenhouse on the diurnal variation and spatial distribution of environmental factors in the greenhouse].

    Science.gov (United States)

    Li, Qing-ming; Zi, Xi-zhen; Yu, Xian-chang

    2011-08-01

    Taking the energy-saving solar greenhouses with the same infrastructure but different sunken depths (0, 0.5, 1.0, and 1.5 m) in Tai' an of Shandong Province as test objects, this paper analyzed the intercepted amount of direct solar radiation energy, and studied the diurnal variation and spatial distribution patterns of environmental factors in the greenhouses on winter solstice (December 20-24, 2009) and summer solstice (June 19-23, 2010). With the increase of sunken depth, the shadow areas in the greenhouses caused by sunken profiles increased gradually, the direct solar radiation energy into the interior of the greenhouses shifted from south to north, and the ratio of ground radiation to back wall radiation decreased gradually. Within the range of 0-1.0 m sunken depth, the air temperature and soil temperature in the greenhouses increased significantly with increasing sunken depth; but when the sunken depth was 1.5 m, the warming effect declined significantly, and the deviation of the lowest soil temperature increased. The deeper the sunken depth, the lower the light intensity and the higher the relative humidity in the greenhouses were. In considering of both lighting and heat preservation, the appropriate sunken depth of energy-saving sunlight greenhouses with a span of 10 m in Tai' an region should be less than 1.0 m.

  1. The isolating effect of greenhouses on arthropod pests: a case-study on Clepsis spectrana (Lepidoptera: Torticidae)

    NARCIS (Netherlands)

    Bos, van den J.

    1983-01-01

    Chapter 1: the environmental conditions in greenhouses differ in many respects from those in the open field. Both the climate and the crops are different. A free exchange between the fauna of the greenhouses and the open air is hampered by the glass walls and roofs. The isolating effect of greenhous

  2. Simple model of photo acoustic system for greenhouse effect

    CERN Document Server

    Fukuhara, Akiko; Ogawa, Naohisa

    2010-01-01

    The simple theoretical basis for photo acoustic (PA) system for studying infrared absorption properties of greenhouse gases is constructed. The amplitude of sound observed in PA depends on the modulation frequency of light pulse. Its dependence can be explained by our simple model. According to this model, sound signal has higher harmonics. The theory and experiment are compared in third and fifth harmonics by spectrum analysis. The theory has the analogy with electric circuits. This analogy helps students for understanding the PA system.

  3. Mars Greenhouses: Concepts and Challenges. Proceedings from a 1999 Workshop

    Science.gov (United States)

    Wheeler, Ray M. (Editor); Martin-Brennan, Cindy (Editor)

    2000-01-01

    Topic covered include :Plants on Mars: On the Next Mission and in the Long Term Future; Bubbles in the Rocks: Natural and Artificial Caves and Cavities as Like Support Structures; Challenges for Bioregenerative Life Support on Mars; Cost Effectiveness Issues; Low Pressure Systems for Plant Growth; Plant Responses to Rarified Atmospheres; Can CO2 be Used as a Pressurizing Gas for Mars Greenhouses?; Inflatable Habitats Technology Development; Development of an Inflatable Greenhouse for a Modular Crop Production System; Mars Inflatable Greenhouse Workshop; Design Needs for Mars Deployable Greenhouse; Preliminary Estimates of the Possibilities for Developing a Deployable Greenhouse for a Planetary Surface Mars; Low Pressure Greenhouse Concepts for Mars; Mars Greenhouse Study: Natural vs. Artificial Lighting; and Wire Culture for an Inflatable Mars Greenhouse and Other Future Inflatable Space Growth Chambers.

  4. China Fights Atmospheric Pollution Effectively

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ China emitted 2.6 billion tons of carbon dioxide and more than 34 million tons of methane in 1994. The decade-old figure, however, is the latest official one about China's emission of greenhouse gases. The nation also joined the Asia-Pacific partnership on clean development and climate this year, together with the United States,India, South Korea, Australia and Japan. While it does not replace the Kyoto Protocol, the partnership instead focuses on regional efforts to cut greenhouse gases emissions. China and the European Union (EU) have also recently signed a joint declaration on climate change,saying the two parties will strengthen co-operation and dialogue on climate change, including clean energy, and promote sustainable development.

  5. [Effects of superphosphate addition on NH3 and greenhouse gas emissions during vegetable waste composting].

    Science.gov (United States)

    Yang, Yan; Sun, Qin-ping; Li, Ni; Liu, Chun-sheng; Li, Ji-jin; Liu, Ben-sheng; Zou, Guo-yuan

    2015-01-01

    To study the effects of superphosphate (SP) on the NH, and greenhouse gas emissions, vegetable waste composting was performed for 27 days using 6 different treatments. In addition to the controls, five vegetable waste mixtures (0.77 m3 each) were treated with different amounts of the SP additive, namely, 5%, 10%, 15%, 20% and 25%. The ammonia volatilization loss and greenhouse gas emissions were measured during composting. Results indicated that the SP additive significantly decreased the ammonia volatilization and greenhouse gas emissions during vegetable waste composting. The additive reduced the total NH3 emission by 4.0% to 16.7%. The total greenhouse gas emissions (CO2-eq) of all treatments with SP additives were decreased by 10.2% to 20.8%, as compared with the controls. The NH3 emission during vegetable waste composting had the highest contribution to the greenhouse effect caused by the four different gases. The amount of NH3 (CO2-eq) from each treatment ranged from 59.90 kg . t-1 to 81.58 kg . t-1; NH3(CO2-eq) accounted for 69% to 77% of the total emissions from the four gases. Therefore, SP is a cost-effective phosphorus-based fertilizer that can be used as an additive during vegetable waste composting to reduce the NH3 and greenhouse gas emissions as well as to improve the value of compost as a fertilizer.

  6. The Effects of Concept Cartoons on Eliminating Students’ Misconceptions: Greenhouse Effect and Global Warming

    Directory of Open Access Journals (Sweden)

    Lale Cerrah Ozsevgeç

    2012-10-01

    Full Text Available The aim of the study is to examine the effects of concept cartoons on eliminating students’ misconceptions about the global warming and greenhouse effect. The sample of the study is consisted of 17 students from the 7 grade of Rize Çay Primary School. Simple experimental study design was used in the study. Test and semi-structured interview were used to collect the data. The results of the study showed that the students had misconceptions about global warming and greenhouse effect. The teaching process comprising concept cartoons treated most of these misconceptions. Students indicated that the teaching process was enjoyable and it eased the students’ remembering of the given knowledge. Based on the results, it was suggested that the teachers should be informed about the usage of concept cartoon in the classroom and combination of different teaching methods which is supported by concept cartoon may be more useful for different science subjects.

  7. Effects of UV-absorbing plastic films on greenhouse whitefly (Homoptera: Aleyrodidae).

    Science.gov (United States)

    Mutwiwa, Urbanus N; Borgemeister, Christian; von Elsner, Burkhard; Tantau, Hans-Juergen

    2005-08-01

    Studies were conducted to investigate the effects of ultraviolet (UV)-absorbing plastic films on the orientation and distribution behavior of the greenhouse whitefly, Trialeurodes vaporariorum (Westwood). In field experiments, small tunnels were constructed and covered with either an UV-transmitting (Thermilux) or UV-absorbing (K-Rose) plastic film. Results show that significantly more whiteflies were recorded in the tunnels with high compared with those with low UV intensities. Moreover, whitefly penetration and dispersion were less inside the UV-deficient tunnels. These results suggest that the type of plastic film used for greenhouse covers may have a significant influence on both the initial immigration and distribution of T. vaporariorum into greenhouses. The possibilities of using UV-absorbing plastic films for whitefly integrated pest management in greenhouses are discussed.

  8. [Effects of fertilizer application on greenhouse vegetable yield: a case study of Shouguang].

    Science.gov (United States)

    Liu, Ping; Li, Yan; Jiang, Li-Hua; Liu, Zhao-Hui; Gao, Xin-Hao; Lin, Hai-Tao; Zheng, Fu-Li; Shi, Jing

    2014-06-01

    Data collected from 51 representative greenhouses of Shouguang through questionnaire survey were analyzed to investigate the effect of chemical fertilizers on vegetable yield, relationship between application of organic manure and yield, and influence factors and evolution rule of fertilizer application rate. The results showed that averages of 3338 kg N x hm(-2), 1710 kg P2O5 x hm(-2) 3446 kg K2O x hm(-2) were applied to greenhouse vegetables annually in Shouguang, 6-14 times as that in the local wheat-maize rotation system. The application rates of chemical N, P, and K fertilizers accounted for about 35%, 49% and 42% of the total input. Increasing application of chemical fertilizers had no significant effect on vegetable yields, while organic manure input significantly increased the vegetable yields. With the increase of greenhouse cultivating time, no significant changes in the input of chemical N, P, and K fertilizers were observed in greenhouse vegetable production while organic manure input decreased significantly. Differences in vegetable species, planting pattern and cultivating time of greenhouses was one of the reasons for large variations in nutrient application rate. In recent more than ten years, organic manure nutrient input increased significantly, chemical N and P fertilizer input presented a downward trend, chemical K fertilizer input increased significantly, and the N/P/K ratio became more and more reasonable in greenhouse vegetable production in Shouguang.

  9. Carbon dioxide emissions from Deccan volcanism and a K/T boundary greenhouse effect

    Science.gov (United States)

    Caldeira, Ken; Rampino, Michael R.

    1990-01-01

    A greenhouse warming caused by increased emissions of carbon dioxide from the Deccan Traps volcanism has been suggested as the cause of the terminal Cretaceous extinctions on land and in the sea. Total eruptive and noneruptive CO2 output by the Deccan eruptions (from 6 to 20 x 10 to the 16th moles) over a period of several hundred thousand years is estimated based on best estimates of the CO2 weight fraction of the original basalts and basaltic melts, the fraction of CO2 degassed, and the volume of the Deccan Traps eruptions. Results of a model designed to estimate the effects of increased CO2 on climate and ocean chemistry suggest that increases in atmospheric pCO2 due to Deccan Traps CO2 emissions would have been less than 75 ppm, leading to a predicted global warming of less than 1 C over several hundred thousand years. It is concluded that the direct climate effects of CO2 emissions from the Deccan eruptions would have been too weak to be an important factor in the end-Cretaceous mass extinctions.

  10. Tree species influence soil-atmosphere fluxes of the greenhouse gases CO2, CH4 and N2O

    Science.gov (United States)

    Steffens, Christina; Vesterdal, Lars; Pfeiffer, Eva-Maria

    2016-04-01

    In the temperate zone, forests are the greatest terrestrial sink for atmospheric CO2, and tree species affect soil C stocks and soil CO2 emissions. When considering the total greenhouse gas (GHG) balance of the forest soil, the relevant GHGs CH4 and N2O should also be considered as they have a higher global warming potential than CO2. The presented data are first results from a field study in a common garden site in Denmark where tree species with ectomycorrhizal colonization (beech - Fagus sylvatica, oak - Quercus robur) and with arbuscular mycorrhizal colonization (maple - Acer pseudoplatanus, ash - Fraxinus excelsior) have been planted in monocultures in adjacent blocks of about 0.25 ha in the year 1973 on former arable land. The soil-atmosphere fluxes of all three gases were measured every second week since August 2015. The hypothesis is that the total GHG efflux from forest soil would differ between species, and that these differences could be related to the type of mycorrhizal association and leaf litter quality. Preliminary results (August to December 2015) indicate that tree species influence the fluxes (converted to CO2-eq) of the three GHGs. Total soil CO2 efflux was in the low end of the range reported for temperate broadleaved forests but similar to the measurements at the same site approximately ten years ago. It was highest under oak (9.6±2.4 g CO2 m-2 d-1) and lowest under maple (5.2±1.6 g CO2 m-2 d-1). In contrast, soil under oak was a small but significant sink for CH4(-0.005±0.003 g CO2-eq m-2 d-1), while there were almost no detectable CH4 fluxes in maple. Emissions of N2O were highest under beech (0.6±0.6 g CO2-eq m-2 d-1) and oak (0.2±0.09 g CO2-eq m-2 d-1) and lowest under ash (0.03±0.04 g CO2-eq m-2 d-1). In the total GHG balance, soil CH4 uptake was negligible (≤0.1% of total emissions). Emissions of N2O (converted to CO2-eq) contributed mycorrhiza and produce leaf litter with a lower lignin:N ratio.

  11. Variability of atmospheric greenhouse gases as a biogeochemical processing signal at regional scale in a karstic ecosystem

    Science.gov (United States)

    Borràs, Sílvia; Vazquez, Eusebi; Morguí, Josep-Anton; Àgueda, Alba; Batet, Oscar; Cañas, Lídia; Curcoll, Roger; Grossi, Claudia; Nofuentes, Manel; Occhipinti, Paola; Rodó, Xavier

    2015-04-01

    The South-eastern area of the Iberian Peninsula is an area where climatic conditions reach extreme climatic conditions during the year, and is also heavily affected by the ENSO and NAO. The Natural Park of Cazorla, Segura de la Sierra and Las Villas is located in this region, and it is the largest protected natural area in Spain (209920 Ha). This area is characterized by important climatic and hydrologic contrasts: although the mean annual precipitation is 770 nm, the karstic soils are the main cause for water scarcity during the summer months, while on the other hand it is in this area where the two main rivers of Southern Spain, the Segura and the Guadalquivir, are born. The protected area comprises many forested landscapes, karstic areas and reservoirs like Tranco de Beas. The temperatures during summer are high, with over 40°C heatwaves occurring each year. But during the winter months, the land surface can be covered by snow for periods of time up until 30 days. The ENSO and NAO influences cause also an important inter annual climatic variability in this area. Under the ENSO, autumnal periods are more humid while the following spring is drier. In this area vegetal Mediterranean communities are dominant. But there are also a high number of endemic species and derelict species typical of temperate climate. Therefore it is a protected area with high specific diversity. Additionally, there is an important agricultural activity in the fringe areas of the Natural Park, mainly for olive production, while inside the Park this activity is focused on mountain wheat production. Therefore the diverse vegetal communities and landscapes can easily be under extreme climatic pressures, affecting in turn the biogeochemical processes at the regional scale. The constant, high-frequency monitoring of greenhouse gases (GHG) (CO2 and CH4) integrates the biogeochemical signal of changes in this area related to the carbon cycle at the regional scale, capturing the high diversity of

  12. Warming effects on greenhouse gas fluxes in peatlands are modulated by vegetation composition.

    Science.gov (United States)

    Ward, Susan E; Ostle, Nicholas J; Oakley, Simon; Quirk, Helen; Henrys, Peter A; Bardgett, Richard D

    2013-10-01

    Understanding the effects of warming on greenhouse gas feedbacks to climate change represents a major global challenge. Most research has focused on direct effects of warming, without considering how concurrent changes in plant communities may alter such effects. Here, we combined vegetation manipulations with warming to investigate their interactive effects on greenhouse gas emissions from peatland. We found that although warming consistently increased respiration, the effect on net ecosystem CO2 exchange depended on vegetation composition. The greatest increase in CO2 sink strength after warming was when shrubs were present, and the greatest decrease when graminoids were present. CH4 was more strongly controlled by vegetation composition than by warming, with largest emissions from graminoid communities. Our results show that plant community composition is a significant modulator of greenhouse gas emissions and their response to warming, and suggest that vegetation change could alter peatland carbon sink strength under future climate change.

  13. Carbon exchange in Western Siberian watershed mires and implication for the greenhouse effect. A spatial temporal modeling approach

    Energy Technology Data Exchange (ETDEWEB)

    Borren, W.

    2007-01-19

    wetter climatic conditions the mire growth could continue much longer, whereas under dryer conditions an earlier termination will occur. Mire drainage leads to aerobic decay of peat and thus to CO2 emission instead of uptake. In a modeling study in a mire catchment containing both drained and undrained parts, the effect of drainage was quantified. The results show that the water table drawdown not only affected the drained mire part, but also influenced the undrained part over a zone of 1-1.5 km. In this zone peat growth and carbon accumulation were decreased. The contribution of a mire system to the greenhouse effect is depending on the exchange of the greenhouse gases CO2 and CH4. CH4 is a much stronger greenhouse gas than CO2, but has a much shorter atmospheric lifetime. With a stocks-and-flows approach the radiative forcing of both gases could be calculated. This approach has been applied in two cases: (1) the northward shift of bioclimatic zones in Western Siberia under 21st century warming and (2) the carbon exchange in a Western Siberian mire resulting from the 3-D dynamic model. The results show that Western Siberian mires form a sink of greenhouse gases at present and have therefore a negative contribution to the greenhouse effect. Under 21st century warming or drainage conditions the mires will turn into a source of greenhouse gases, thus enhancing the greenhouse effect. However, in the case of warming the increase in CH4 emission will be overruled by the increase in CO2 uptake on the long term, thus leading to a negative contribution again.

  14. Changes in Arctic vegetation amplify high-latitude warming through the greenhouse effect.

    Science.gov (United States)

    Swann, Abigail L; Fung, Inez Y; Levis, Samuel; Bonan, Gordon B; Doney, Scott C

    2010-01-26

    Arctic climate is projected to change dramatically in the next 100 years and increases in temperature will likely lead to changes in the distribution and makeup of the Arctic biosphere. A largely deciduous ecosystem has been suggested as a possible landscape for future Arctic vegetation and is seen in paleo-records of warm times in the past. Here we use a global climate model with an interactive terrestrial biosphere to investigate the effects of adding deciduous trees on bare ground at high northern latitudes. We find that the top-of-atmosphere radiative imbalance from enhanced transpiration (associated with the expanded forest cover) is up to 1.5 times larger than the forcing due to albedo change from the forest. Furthermore, the greenhouse warming by additional water vapor melts sea-ice and triggers a positive feedback through changes in ocean albedo and evaporation. Land surface albedo change is considered to be the dominant mechanism by which trees directly modify climate at high-latitudes, but our findings suggest an additional mechanism through transpiration of water vapor and feedbacks from the ocean and sea-ice.

  15. Summer fluxes of atmospheric greenhouse gases N{sub 2}O, CH{sub 4} and CO{sub 2} from mangrove soil in South China

    Energy Technology Data Exchange (ETDEWEB)

    Chen, G.C. [Department of Biology and Chemistry, City University of Hong Kong, Hong Kong SAR (China); Tam, N.F.Y., E-mail: bhntam@cityu.edu.hk [Department of Biology and Chemistry, City University of Hong Kong, Hong Kong SAR (China); Ye, Y. [State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, Fujian (China)

    2010-06-01

    The atmospheric fluxes of N{sub 2}O, CH{sub 4} and CO{sub 2} from the soil in four mangrove swamps in Shenzhen and Hong Kong, South China were investigated in the summer of 2008. The fluxes ranged from 0.14 to 23.83 {mu}mol m{sup -2} h{sup -1}, 11.9 to 5168.6 {mu}mol m{sup -2} h{sup -1} and 0.69 to 20.56 mmol m{sup -2} h{sup -1} for N{sub 2}O, CH{sub 4} and CO{sub 2}, respectively. Futian mangrove swamp in Shenzhen had the highest greenhouse gas fluxes, followed by Mai Po mangrove in Hong Kong. Sha Kong Tsuen and Yung Shue O mangroves in Hong Kong had similar, low fluxes. The differences in both N{sub 2}O and CH{sub 4} fluxes among different tidal positions, the landward, seaward and bare mudflat, in each swamp were insignificant. The N{sub 2}O and CO{sub 2} fluxes were positively correlated with the soil organic carbon, total nitrogen, total phosphate, total iron and NH{sub 4}{sup +}-N contents, as well as the soil porosity. However, only soil NH{sub 4}{sup +}-N concentration had significant effects on CH{sub 4} fluxes.

  16. Effects of land use on greenhouse gas fluxes and soil properties of wetland catchments in the Prairie Pothole Region of North America

    Science.gov (United States)

    Tangen, Brian A.; Finocchiaro, Raymond G.; Gleason, Robert A.

    2015-01-01

    Wetland restoration has been suggested as policy goal with multiple environmental benefits including enhancement of atmospheric carbon sequestration. However, there are concerns that increased methane (CH4) emissions associated with restoration may outweigh potential benefits. A comprehensive, 4-year study of 119 wetland catchments was conducted in the Prairie Pothole Region of the north-central U.S. to assess the effects of land use on greenhouse gas (GHG) fluxes and soil properties.

  17. Advection from the North Atlantic as the Forcing of Winter Greenhouse Effect Over Europe

    Science.gov (United States)

    Otterman, J.; Angell, J.; Atlas, R.; Bungato, D.; Shubert, S.; Starr, David OC.; Susskind, J.; Wu, M.-L. C.

    2002-01-01

    In winter, large interannual fluctuations in the surface temperature are observed over central Europe. Comparing warm February 1990 with cold February 1996, a satellite-retrieved surface (skin) temperature difference of 9.8 K is observed for the region 50-60 degrees N; 5-35 degrees E. Previous studies show that advection from the North Atlantic constitutes the forcing to such fluctuations. The advection is quantified by Index I(sub na), the average of the ocean-surface wind speed over the eastern North Atlantic when the direction is from the southwest (when the wind is from another direction, it counts as a zero speed to the average). Average I(sub na) for February 1990 was 10.6 m/s, but for February 1996 I(sub na) was only 2.4 m/s. A large value of I(sub na) means a strong southwesterly flow which brings warm and moist air into central Europe at low level, producing a steeper tropospheric lapse rate. Strong ascending motions at 700 mb are observed in association with the occurrence of enhanced warm, moist advection from the ocean in February 1990 producing clouds and precipitation. Total precipitable water and cloud-cover fraction have larger values in February 1990 than in 1996. The difference in the greenhouse effect between these two scenarios, this reduction in heat loss to space, can be translated into a virtual radiative heating of 2.6 W/square m above the February 1990 surface/atmosphere system, which contributes to a warming of the surface on the order of 2.6 K. Accepting this estimate as quantitatively meaningful, we evaluate the direct effect, the rise in the surface temperature in Europe as a result of maritime-air inflow, as 7.2 K (9.8 K-2.6 K). Thus, fractional reinforcement by the greenhouse effect is 2.6/7.2, or 36%, a substantial positive feedback.

  18. Effects of Different Rootstocks on the Growth and Fruit Quality of Greenhouse Cucumber in Early Spring

    Institute of Scientific and Technical Information of China (English)

    LIU Bing; ZHANG Tianwei; ZHAO Jiayu; JIANG Xinmei

    2009-01-01

    Different pumpkin rootstocks were used to study the effects of different rootstocks on the growth and fruit quality of greenhouse cucumber in early spring. The results showed that the grafted cucumber could significantly improve the production, and different rootstock had a certain effect on the survival rate and fruit quality. Jinhuanghou and Fengyijiajiewang as rootstock had the highest survival rate, which were 79.0% and 70.7%, respectively. As rootstocks of greenhouse cucumber, Jinhuanghou, Lvzhoujuxing,Fengyi, Huofenghuang, and Dawei No.17 were better than others according to taste, and Heizinangua, Jinhuanghou, Fengyi,Huofenghuang, and Dawei No. 17 were better according to output.

  19. Effect of solid and aqueous extract of vermicompost on growth characteristics of tomato and greenhouse whitefly (Trialeurodes vaporariorum)

    OpenAIRE

    A. Peimani Foroushani; N. Poorjavad; M. Haghigh; J. Khajehali

    2016-01-01

    Considering the increase of using vermicompost fertilizers in greenhouse cultivation, effect of vermicompost application on growth characteristics of tomato and one of its major pests [greenhouse whitefly, Trialeurodes vaporariorum (Hem:Aleyrodidae)] was investigated. The experiment consisted of five treatments: control (without vermicompost), 30% and 60% solid vermicompost fertilizer, and 40% and 20% aqueous extracts of vermicompost. Effect of vermicompost on greenhouse whitefly was tested f...

  20. Can intense forest fertilization be considered a sustainable management practice in the context of greenhouse gas exchange between soils and the atmosphere?

    Science.gov (United States)

    Oquist, Mats G.; Egnell, Gustaf; Nilsson, Mats

    2016-04-01

    The demand for forest biomass is increasing and there is large potential for increasing biomass production of northern forest ecosystems by various management strategies involving N fertilization. Increased biomass production also leads to more atmospheric carbon sequestration that potentially can mitigate climate change. N fertilization has been shown to increase biomass production and to decrease soil respiration rates. However, the potential increase in N2O emissions following N addition may counteract the sustainability of such management practices in terms of its impact on the sink/source relationship of greenhouse gases. Here we evaluate the effect of various N addition intensities on the soil-atmosphere exchange of CO2 and N2O in a long-term field experiment in a boreal Scots pine (Pinus sylvestris) forest stand. The stand was planted in 1953 and the experiment was established in 1974 with annual N addition at four levels (N0, N1, N2, and N3 receiving 0, 35, 70, and 110 kg N ha-1 year-1, respectively) organized in a randomized block design (n=3) in plots of 30x30m. The high (N3) and intermediate (N2) N addition levels were terminated in 1990 and 2006, respectively, and offered an opportunity to investigate recovery of greenhouse gas exchange following high N loading. Soil-atmosphere exchange of GHGs were estimated weekly during 2010-2011 based on static chamber measurements during the snow free period and snow concentration gradients during winter. In the ongoing treatment (N1) the annual N2O emissions were 25 mg N2O m-2 yr-1, as compared to 6 mg N2O m-2 yr-1 in the control plots, representing a ca 4-fold significant increase due to N-addition. The N2O-N loss from the treatment corresponded to ca 0.5% of the annually added N (35 kg N ha-1). In the N2 treatment (terminated in 2006) annual N2O emissions were 15 mg N2O m-2 yr-1, while in the N3 treatment N2O emissions were the same as in the control plots with no N-additions. Thus the system has capacity to

  1. Impact of nitrogen fertilization on soil–Atmosphere greenhouse gas exchanges in eucalypt plantations with different soil characteristics in southern China

    Science.gov (United States)

    Zhang, Kai; Zheng, Hua; Chen, Falin; Li, Ruida; Yang, Miao; Ouyang, Zhiyun; Lan, Jun; Xiang, Xuewu

    2017-01-01

    Nitrogen (N) fertilization is necessary to sustain productivity in eucalypt plantations, but it can increase the risk of greenhouse gas emissions. However, the response of soil greenhouse gas emissions to N fertilization might be influenced by soil characteristics, which is of great significance for accurately assessing greenhouse gas budgets and scientific fertilization in plantations. We conducted a two-year N fertilization experiment (control [CK], low N [LN], middle N [MN] and high N [HN] fertilization) in two eucalypt plantations with different soil characteristics (higher and lower soil organic carbon sites [HSOC and LSOC]) in Guangxi, China, and assessed soil–atmosphere greenhouse gas exchanges. The annual mean fluxes of soil CO2, CH4, and N2O were separately 153–266 mg m-2 h-1, -55 –-40 μg m-2 h-1, and 11–95 μg m-2 h-1, with CO2 and N2O emissions showing significant seasonal variations. N fertilization significantly increased soil CO2 and N2O emissions and decreased CH4 uptake at both sites. There were significant interactions of N fertilization and SOC level on soil CO2 and N2O emissions. At the LSOC site, the annual mean flux of soil CO2 emission was only significantly higher than the CK treatment in the HN treatment, but, at the HSOC site, the annual mean flux of soil CO2 emission was significantly higher for both the LN (or MN) and HN treatments in comparison to the CK treatment. Under the CK and LN treatments, the annual mean flux of N2O emission was not significantly different between HSOC and LSOC sites, but under the HN treatment, it was significantly higher in the HSOC site than in the LSOC site. Correlation analysis showed that changes in soil CO2 and N2O emissions were significantly related to soil dissolved organic carbon, ammonia, nitrate and pH. Our results suggested significant interactions of N fertilization and soil characteristics existed in soil–atmosphere greenhouse gas exchanges, which should be considered in assessing

  2. Assessment of the impact of the greenhouse gas emission and sink scenarios in Finland on radiative forcing and greenhouse effect

    Energy Technology Data Exchange (ETDEWEB)

    Savolainen, I.; Sinisalo, J.; Pipatti, R. [Technical Research Centre of Finland, Espoo (Finland)

    1996-12-31

    The objective of this work is to study greenhouse gas emissions and sinks and their greenhouse impact as a function of time. The greenhouse impact is expressed in terms of global average radiative forcing, which measures the perturbation in the Earth`s radiation budget. Radiative forcing is calculated on the basis of the concentration changes of the greenhouse gases and the radiation absorption properties of the gases. It takes into account the relatively slow changes in the concentrations due to natural removal and transformation processes and also allows a comparison of the impact of various greenhouse gases and their possible control options as a function of time. In addition to the applications mentioned above, the anthropogenic greenhouse gas emission histories of Nordic countries have been estimated, and the radiative forcing caused by them has been calculated with REFUGE. The dynamic impact of aerosol emissions both from the global point of view and in the context of different energy sources (coal, oil and natural gas) have also been studied. In some instances the caused radiative forcing has been examined on a per capita basis. The radiative forcing calculations contain considerable uncertainty due to inaccurately known factors at several stages of the calculation (emission estimation, concentration calculation and radiative forcing calculation). The total uncertainty of the results is typically on the order of +- 40 %, when absolute values are used. If the results are used in a relative way, e.g. to compare the impacts of different scenarios, the final uncertainty is considerably less (typically + 10 %), due to correlations in almost all stages of the calculation process

  3. The Effect of Vegetation Coverage and Greenhouse Area on the Performance of an Earth-to-Air Heat Exchanger in Cooling Mode of Greenhouse

    Directory of Open Access Journals (Sweden)

    M Mohammadi Mogharreb

    2013-02-01

    Full Text Available The underground temperature at a depth of about three to four meters is almost constant during the year. As a result in summer the underground is cooler than the ambient temperature. This potential is considered for greenhouse cooling by using an Earth-to-Air Heat Exchanger (EAHE. In this research the effects of two parameters were investigated: a the area of greenhouse in three levels of 9, 18, 27 m2 and b the percent of vegetation coverage inside the greenhouse in three levels of 0%, 50%, 100% on the performance of EAHE. The experimental design was factorial experiment in a randomized complete block design. The parameters of greenhouse’s inside temperature, thermal energy exchange and coefficient of performance (COP were considered in cooling mode. As one of the remarkable results it was observed that the closed loop utilization of the system was infeasible in cooling mode. This was mainly due to the occurrence of vapor distillation inside the underground pipes and hence the blockages of the air flow. Also the effect of area and the percent of vegetation coverage were significant on the performance of EAHE. The highest average temperature difference between the temperature of testimonial greenhouse and the temperature of greenhouse was observed in treatment of 100% vegetation coverage and 9 m2 floor area which was measured as 9.6°C. The least average temperature difference in the treatment without vegetation coverage and 27 m2 floor area was measured as 5.2 °C. Considering thermal energy exchange in cooling greenhouse with open loop, the best treatment determined for EAHE in this research was the one with 9 m2 floor area and 100% of vegetation coverage.

  4. On the meaning of feedback parameter, transient climate response, and the greenhouse effect: Basic considerations and the discussion of uncertainties

    CERN Document Server

    Kramm, Gerhard

    2010-01-01

    In this paper we discuss the meaning of feedback parameter, greenhouse effect and transient climate response usually related to the globally averaged energy balance model of Schneider and Mass. After scrutinizing this model and the corresponding planetary radiation balance we state that (a) the this globally averaged energy balance model is flawed by unsuitable physical considerations, (b) the planetary radiation balance for an Earth in the absence of an atmosphere is fraught by the inappropriate assumption of a uniform surface temperature, the so-called radiative equilibrium temperature of about 255 K, and (c) the effect of the radiative anthropogenic forcing, considered as a perturbation to the natural system, is much smaller than the uncertainty involved in the solution of the model of Schneider and Mass. This uncertainty is mainly related to the empirical constants suggested by various authors and used for predicting the emission of infrared radiation by the Earth's skin. Furthermore, after inserting the ...

  5. Quantifying the effects of nitrogen on fruit growth and yield of cucumber crop in greenhouses

    NARCIS (Netherlands)

    Dai, J.; Liu, S.; Zhang, W.; Xu, R.; Luo, W.; Yin, X.; Han, L.; Chen, S.

    2011-01-01

    Nitrogen supply can improve crop growth and yield. An over-use of nitrogen fertilizer in greenhouse crop productions, however, causes many environmental problems. The aim of this study was to quantify the effects of nitrogen on fruit growth and yield so as to facilitate the optimization of nitrogen

  6. Potato (Solanum tuberosum) greenhouse tuber production as an assay for asexual reproduction effects from herbicides

    Science.gov (United States)

    The present study determined whether young potato plants can be used as an assay to indicate potential effects of pesticides on asexual reproduction. Solanum tuberosum (Russet Burbank) plants were grown from seed pieces in a mineral soil in pots under greenhouse conditions. Plant...

  7. Greenhouse Effect: Temperature of a Metal Sphere Surrounded by a Glass Shell and Heated by Sunlight

    Science.gov (United States)

    Nguyen, Phuc H.; Matzner, Richard A.

    2012-01-01

    We study the greenhouse effect on a model satellite consisting of a tungsten sphere surrounded by a thin spherical, concentric glass shell, with a small gap between the sphere and the shell. The system sits in vacuum and is heated by sunlight incident along the "z"-axis. This development is a generalization of the simple treatment of the…

  8. Spaceship Nigeria: A Topic Study for Global Warming, Greenhouse Effect and Ozone Layer Depletion.

    Science.gov (United States)

    Okebukola, Peter; Akpan, Ben B.

    1997-01-01

    Explains the concept of a topic study, how it meets the needs of teachers seeking to integrate their teaching, and how it is especially well suited for environmental education. Outlines curriculum for a topic study on the greenhouse effect and ozone layer depletion. (DDR)

  9. Student Teacher Understanding of the Greenhouse Effect, Ozone Layer Depletion, and Acid Rain.

    Science.gov (United States)

    Dove, Jane

    1996-01-01

    Describes the results of a survey designed to ascertain details of student teachers' knowledge and misconceptions about the greenhouse effect, acid rain, and ozone layer depletion. Results indicate familiarity with the issues but little understanding of the concepts involved and many commonly held misconceptions. (JRH)

  10. Understanding the Greenhouse Effect by Embodiment - Analysing and Using Students' and Scientists' Conceptual Resources

    Science.gov (United States)

    Niebert, Kai; Gropengießer, Harald

    2014-01-01

    Over the last 20 years, science education studies have reported that there are very different understandings among students of science regarding the key aspects of climate change. We used the cognitive linguistic framework of experientialism to shed new light on this valuable pool of studies to identify the conceptual resources of understanding climate change. In our study, we interviewed 35 secondary school students on their understanding of the greenhouse effect and analysed the conceptions of climate scientists as drawn from textbooks and research reports. We analysed all data by metaphor analysis and qualitative content analysis to gain insight into students' and scientists' resources for understanding. In our analysis, we found that students and scientists refer to the same schemata to understand the greenhouse effect. We categorised their conceptions into three different principles the conceptions are based on: warming by more input, warming by less output, and warming by a new equilibrium. By interrelating students' and scientists' conceptions, we identified the students' learning demand: First, our students were afforded with experiences regarding the interactions of electromagnetic radiation and CO2. Second, our students reflected about the experience-based schemata they use as source domains for metaphorical understanding of the greenhouse effect. By uncovering the-mostly unconscious-deployed schemata, we gave students access to their source domains. We implemented these teaching guidelines in interventions and evaluated them in teaching experiments to develop evidence-based and theory-guided learning activities on the greenhouse effect.

  11. The Effect of Greenhouse Gas Mitigation on Drought Impacts in the U.S.

    Science.gov (United States)

    In this paper, we present a methodology for analyzing the economic benefits in the U.S. of changes in drought frequency and severity due to global greenhouse gas (GHG) mitigation. We construct reduced-form models of the effect of drought on agriculture and reservoir recreation i...

  12. Greenhouse Effect in the Classroom: A Project- and Laboratory-Based Curriculum.

    Science.gov (United States)

    Lueddecke, Susann B.; Pinter, Nicholas; McManus, Scott A.

    2001-01-01

    Tests a multifaceted curriculum for use in introductory earth science classes from the secondary school to the introductory undergraduate level. Simulates the greenhouse effect with two fish tanks, heat lamps, and thermometers. Uses a hands-on science approach to develop a deeper understanding of the climate system among students. (Contains 28…

  13. Factor Analysis of Drawings: Application to College Student Models of the Greenhouse Effect

    Science.gov (United States)

    Libarkin, Julie C.; Thomas, Stephen R.; Ording, Gabriel

    2015-01-01

    Exploratory factor analysis was used to identify models underlying drawings of the greenhouse effect made by over 200 entering university freshmen. Initial content analysis allowed deconstruction of drawings into salient features, with grouping of these features via factor analysis. A resulting 4-factor solution explains 62% of the data variance,…

  14. Discussing the Greenhouse Effect: Children's Collaborative Discourse Reasoning and Conceptual Change.

    Science.gov (United States)

    Mason, Lucia; Santi, Marina

    1998-01-01

    Investigates fifth-grade students' conceptual changes toward the greenhouse effect and global warming due to sociocognitive interaction developed in small and large group discussion in an authentic classroom context during an environmental education unit. Classroom discussions led the children to integrate new scientific knowledge into their…

  15. The Anthropogenic "Greenhouse Effect": Greek Prospective Primary Teachers' Ideas about Causes, Consequences and Cures

    Science.gov (United States)

    Ikonomidis, Simos; Papanastasiou, Dimitris; Melas, Dimitris; Avgoloupis, Stavros

    2012-01-01

    This study explores the ideas of Greek prospective primary teachers about the anthropogenic greenhouse effect, particularly about its causes, consequences and cures. For this purpose, a survey was conducted: 265 prospective teachers completed a closed-form questionnaire. The results showed serious misconceptions in all areas (causes, consequences…

  16. Australian Students' Appreciation of the Greenhouse Effect and the Ozone Hole.

    Science.gov (United States)

    Fisher, Brian

    1998-01-01

    Examines students' explanations of the greenhouse effect and the hole in the ozone layer, using a life-world and scientific dichotomy. Illuminates ideas often expressed in classrooms and sheds light on the progression in students' developing powers of explanation. Contains 17 references. (DDR)

  17. Effects of CO2 concentration on photosynthesis, transpiration and production of greenhouse fruit vegetable crops.

    NARCIS (Netherlands)

    Nederhoff, E.M.

    1994-01-01

    The effect of the C0 2 concentration of the greenhouse air (C) in the range 200 to 1100 μmol mol -1was investigated in tomato ( Lycopersicon esculentum Mill.), cucumber ( Cucumis sativus L.), sweet pepper ( Capsicum annuum L.) and eggplant ( Solanum melongena L.), grown in gree

  18. Effect of electrical conductivity, fruit pruning, and truss position on quality in greenhouse tomato fruit

    NARCIS (Netherlands)

    Fanasca, S.; Martino, A.; Heuvelink, E.; Stanghellini, C.

    2007-01-01

    The combined effects of electrical conductivity (an EC of 2.5 dS m-1 or 8 dS m-1 in the root zone) and fruit pruning (three or six fruit per truss) on tomato fruit quality were studied in a greenhouse experiment, planted in January 2005. Taste-related attributes [dry matter content (DM), total solub

  19. Modelling the effect of supplementary lighting on production and light utilisation efficiency of greenhouse crops.

    NARCIS (Netherlands)

    Koning, de J.C.M.

    1997-01-01

    The effect of supplementary lighting (SL) on dry matter production of greenhouse crops is predictable with ALSIM, a new crop growth model based on SUCROS87. The light utilization efficiency (LUE), defined as daily dry matter production divided by the daily photosynthetic photon flux is a parameter f

  20. Improving Students' Conceptual Understanding of the Greenhouse Effect Using Theory-Based Learning Materials that Promote Deep Learning

    Science.gov (United States)

    Reinfried, Sibylle; Aeschbacher, Urs; Rottermann, Benno

    2012-01-01

    Students' everyday ideas of the greenhouse effect are difficult to change. Environmental education faces the challenge of developing instructional settings that foster students' conceptual understanding concept of the greenhouse effect in order to understand global warming. To facilitate students' conceptual development with regard to the…

  1. Precipitation rates and atmospheric heat transport during the Cenomanian greenhouse warming in North America: Estimates from a stable isotope mass-balance model

    Science.gov (United States)

    Ufnar, David F.; Ludvigson, Greg A.; Gonzalez, L.; Grocke, D.R.

    2008-01-01

    Stable isotope mass-balance modeling results of meteoric ??18O values from the Cenomanian Stage of the Cretaceous Western Interior Basin (KWIB) suggest that precipitation and evaporation fluxes were greater than that of the present and significantly different from simulations of Albian KWIB paleohydrology. Sphaerosiderite meteoric ??18O values have been compiled from the Lower Tuscaloosa Formation of southwestern Mississippi (25??N paleolatitude), The Dakota Formation Rose Creek Pit, Fairbury Nebraska (35??N) and the Dunvegan Formation of eastern British Columbia (55??N paleolatitude). These paleosol siderite ??18O values define a paleolatitudinal gradient ranging from - 4.2??? VPDB at 25??N to - 12.5??? VPDB at 55??N. This trend is significantly steeper and more depleted than a modern theoretical siderite gradient (25??N: - 1.7???; 65??N: - 5.6??? VPDB ), and a Holocene meteoric calcite trend (27??N: - 3.6???; 67??N: - 7.4??? VPDB). The Cenomanian gradient is also comparatively steeper than the Albian trend determined for the KWIB in the mid- to high latitudes. The steep latitudinal trend in meteoric ??18O values may be the result of increased precipitation and evaporation fluxes (amount effects) under a more vigorous greenhouse-world hydrologic cycle. A stable-isotope mass-balance model has been used to generate estimates of precipitation and evaporation fluxes and precipitation rates. Estimates of Cenomanian precipitation rates based upon the mass-balance modeling of the KWIB range from 1400??mm/yr at 25??N paleolatitude to 3600??mm/yr at 45??N paleolatitude. The precipitation-evaporation (P-E) flux values were used to delineate zones of moisture surplus and moisture deficit. Comparisons between Cenomanian P-E and modern theoretical siderite, and Holocene calcite latitudinal trends shows an amplification of low-latitude moisture deficits between 5-25??N paleolatitude and moisture surpluses between 40-60??N paleolatitude. The low-latitude moisture deficits

  2. Effects of biochar addition on greenhouse gas emissions and microbial responses in a short-term laboratory experiment.

    Science.gov (United States)

    Yoo, Gayoung; Kang, Hojeong

    2012-01-01

    Biochar application to soil has drawn much attention as a strategy to sequester atmospheric carbon in soil ecosystems. The applicability of this strategy as a climate change mitigation option is limited by our understanding of the mechanisms responsible for the observed changes in greenhouse gas emissions from soils, microbial responses, and soil fertility changes. We conducted an 8-wk laboratory incubation using soils from PASTURE (silt loam) and RICE PADDY (silt loam) sites with and without two types of biochar (biochar from swine manure [CHAR-M] and from barley stover [CHAR-B]). Responses to addition of the different biochars varied with the soil source. Addition of CHAR-B did not change CO and CH evolution from the PASTURE or the RICE PADDY soils, but there was a decrease in NO emissions from the PASTURE soil. The effects of CHAR-M addition on greenhouse gas emissions were different for the soils. The most substantial change was an increase in NO emissions from the RICE PADDY soil. This result was attributed to a combination of abundant denitrifiers in this soil and increased net nitrogen mineralization. Soil phosphatase and N-acetylglucosaminidase activity in the CHAR-B-treated soils was enhanced compared with the controls for both soils. Fungal biomass was higher in the CHAR-B-treated RICE PADDY soil. From our results, we suggest CHAR-B to be an appropriate amendment for the PASTURE and RICE PADDY soils because it provides increased nitrogen availability and microbial activity with no net increase in greenhouse gas emissions. Application of CHAR-M to RICE PADDY soils could result in excess nitrogen availability, which may increase NO emissions and possible NO leaching problems. Thus, this study confirms that the ability of environmentally sound biochar additions to sequester carbon in soils depends on the characteristics of the receiving soil as well as the nature of the biochar.

  3. Soil management options to sequester carbon and mitigate the greenhouse effect

    Energy Technology Data Exchange (ETDEWEB)

    Batjes, N.H. [International Soil Reference and Information Centre ISRIC, ICSU World Data Centre for Soils, Wageningen (Netherlands)

    2000-07-01

    The imbalance between global sources and sinks in the global budget of atmospheric CO2 is one of the most important problems in the study of global change. At present there is a 'missing sink' of about 1-2 Pg C/yr. It is likely that a major part of this sink for carbon is to be found in the functioning of terrestrial ecosystems. The Kyoto Protocol currently restricts the allowable terrestrial sequestration of carbon to strictly defined cases of 'afforestation, reforestation and deforestation'. Appropriate conservation and management of the terrestrial natural resources and especially of soils, however, can substantially reduce the buildup of atmospheric greenhouse gases over the next 25 to 50 years while new, 'clean' technologies for energy production are being developed and overall anthropogenic emissions are being curtailed. 1 ref.

  4. Greenhouse gases regional fluxes estimated from atmospheric measurements; Estimation des flux de gaz a effet de serre a l'echelle regionale a partir de mesures atmospheriques

    Energy Technology Data Exchange (ETDEWEB)

    Messager, C

    2007-07-15

    build up a new system to measure continuously CO{sub 2} (or CO), CH{sub 4}, N{sub 2}O and SF{sub 6} mixing ratios. It is based on a commercial gas chromatograph (Agilent 6890N) which have been modified to reach better precision. Reproducibility computed with a target gas on a 24 hours time step gives: 0.06 ppm for CO{sub 2}, 1.4 ppb for CO, 0.7 ppb for CH{sub 4}, 0.2 ppb for N{sub 2}O and 0.05 ppt for SF{sub 6}. The instrument's run is fully automated, an air sample analysis takes about 5 minutes. In July 2006, I install instrumentation on a telecommunication tall tower (200 m) situated near Orleans forest in Trainou, to monitor continuously greenhouse gases (CO{sub 2}, CH{sub 4}, N{sub 2}O, SF{sub 6}), atmospheric tracers (CO, Radon-222) and meteorological parameters. Intake lines were installed at 3 levels (50, 100 and 180 m) and allow us to sample air masses along the vertical. Continuous measurement started in January 2007. I used Mace Head (Ireland) and Gif-sur-Yvette continuous measurements to estimate major greenhouse gases emission fluxes at regional scale. To make the link between atmospheric measurements and surface fluxes, we need to quantify dilution due to atmospheric transport. I used Radon-222 as tracer (radon tracer method) and planetary boundary layer heights estimates from ECMWF model (boundary layer budget method) to parameterize atmospheric transport. In both cases I compared results to available emission inventories. (author)

  5. Taxation of multiple greenhouse gases and the effects on income distribution : A case study of the Netherlands

    NARCIS (Netherlands)

    Kerkhof, Annemarie C.; Moll, Henri C.; Drissen, Eric; Wilting, Harry C.

    2008-01-01

    Current economic instruments aimed at climate change mitigation focus on CO2 emissions only, but the Kyoto Protocol refers to other greenhouse gases (GHG) as well as CO2. These are CH4, N2O, HFCs, PFCs and SF6. Taxation of multiple greenhouse gases improves the cost-effectiveness of climate change m

  6. Priority Processing of Effective Packing Elements on Increasing Greenhouse Products Exports in Viewpoint of Russian Reporters (Case Study of Greenhouse Cucumber

    Directory of Open Access Journals (Sweden)

    Issa Fahim

    2012-12-01

    Full Text Available This research analyzed Priority processing of effective packing elements on increasing greenhouse products exports in viewpoint of Russian reporters. Statistics society of the research includes 44 people. Provided questionnaire was distributed among them which 30 questionnaire were returned. This is a questionnaire research in which questionnaire comprises two sections. To process the priority of packing elements from greenhouse products average index was used. To answer the main question of research, “Weather packing elements of goods influences increasing greenhouse products exports to Russia in viewpoint of Russian reports?” We examined five equations which are explained in the form of five hypotheses. In this research we try to determine that in view point of Russia reporter which elements of packing greenhouse cucumber has a meaningful relation to increasing exports and in other words, between which element and increasing exports to Russia there is no special relation. After doing some studies, interviews and distributing questionnaires, results showed that elements of package color, package weight and facility of opening the package influence increasing exports and in other side, two elements of package quality and package compatibility with environment don’t influence increasing exports.

  7. Biochar and manure effects on net nitrogen mineralization and greenhouse gas emissions from calcareous soil under corn

    Science.gov (United States)

    Few multiyear field studies have examined the impacts of a one-time biochar application on net N mineralization and greenhouse gas emissions in an irrigated, calcareous soil; yet such applications are hypothesized as a means of sequestering atmospheric CO2 and improving soil quality. We fall-applie...

  8. Effects of 17β-estradiol on emissions of greenhouse gases in simulative natural water body.

    Science.gov (United States)

    Ruan, Aidong; Zhao, Ying; Liu, Chenxiao; Zong, Fengjiao; Yu, Zhongbo

    2015-05-01

    Environmental estrogens are widely spread across the world and are increasingly thought of as serious contaminators. The present study looks at the influence of different concentrations of 17β-estradiol on greenhouse gas emissions (CO2 , CH4 , and N2 O) in simulated systems to explore the relationship between environmental estrogen-pollution and greenhouse gas emissions in natural water bodies. The present study finds that 17β-estradiol pollution in simulated systems has significant promoting effects on the emissions of CH4 and CO2 , although no significant effects on N2 O emissions. The present study indicates that 17β-estradiol has different effects on the different elements cycles; the mechanism of microbial ecology is under review.

  9. Repellent effects of pongam oil on settlement and oviposition of the common greenhouse whitefly Trialeurodes vaporariorum on chrysanthemum

    Institute of Scientific and Technical Information of China (English)

    ROMAN PAVELA; GERHARD HERDA

    2007-01-01

    The repellent activities, including host deterrence and anti-oviposion, of pongam oil against the adults of the common greenhouse whitefly Trialeurodes vaporariorum Westwood in greenhouses were tested. Chrysanthemum plants treated with different concentrations (0.5%-2.0%) of water-suspended pongam oil showed relatively longlasting host deterrent and anti-oviposition effects on the adults of greenhouse whitefly. Although the repellent effect declined in time and concentration, strong effects on the reduction of oviposition were found, which lasts, dependent on concentration at least 12 days after application.

  10. Biochar carbon stability and effect on greenhouse gas emissions

    DEFF Research Database (Denmark)

    Bruun, Esben Wilson; Cross, Andrew; Hammond, Jim;

    2016-01-01

    on the biochar quality is necessary in order to produce the most beneficial biochars for soil application. Beside carbon sequestration in soil biochar may improve the GHG balance by reducing N2O and CH4 soil emissions, although contrasting results are found in the literature. The mechanisms behind......As demonstrated by several scientific studies there is no doubt that biochar in general is very recalcitrant compared to other organic matter additions and soil organic matter fractions and also that it is possible to sequester carbon at a climate change relevant time scale (~100 years or more......) by soil application of biochar. However, the carbon stability of biochar in soil is strongly correlated with the degree of thermal alteration of the original feedstock (the lower the temperature, the larger the labile fraction) and in depth understanding of the technology used and its effect...

  11. Reservoir Greenhouse Gas Emissions at Russian HPP

    Energy Technology Data Exchange (ETDEWEB)

    Fedorov, M. P.; Elistratov, V. V.; Maslikov, V. I.; Sidorenko, G. I.; Chusov, A. N.; Atrashenok, V. P.; Molodtsov, D. V. [St. Petersburg State Polytechnic University (Russian Federation); Savvichev, A. S. [Russian Academy of Sciences, S. N. Vinogradskii Institute of Microbiology (Russian Federation); Zinchenko, A. V. [A. I. Voeikov Main Geophysical Observatory (Russian Federation)

    2015-05-15

    Studies of greenhouse-gas emissions from the surfaces of the world’s reservoirs, which has demonstrated ambiguity of assessments of the effect of reservoirs on greenhouse-gas emissions to the atmosphere, is analyzed. It is recommended that greenhouse- gas emissions from various reservoirs be assessed by the procedure “GHG Measurement Guidelines for Fresh Water Reservoirs” (2010) for the purpose of creating a data base with results of standardized measurements. Aprogram for research into greenhouse-gas emissions is being developed at the St. Petersburg Polytechnic University in conformity with the IHA procedure at the reservoirs impounded by the Sayano-Shushenskaya and Mainskaya HPP operated by the RusHydro Co.

  12. Multiagency Initiative to Provide Greenhouse Gas Information

    Science.gov (United States)

    Boland, Stacey W.; Duren, Riley M.

    2009-11-01

    Global Greenhouse Gas Information System Workshop; Albuquerque, New Mexico, 20-22 May 2009; The second Greenhouse Gas Information System (GHGIS) workshop brought together 74 representatives from 28 organizations including U.S. government agencies, national laboratories, and members of the academic community to address issues related to the understanding, operational monitoring, and tracking of greenhouse gas emissions and carbon offsets. The workshop was held at Sandia National Laboratories and organized by an interagency collaboration among NASA centers, Department of Energy laboratories, and the U.S. National Oceanic and Atmospheric Administration. It was motivated by the perceived need for an integrated interagency, community-wide initiative to provide information about greenhouse gas sources and sinks at policy-relevant temporal and spatial scales. Such an initiative could significantly enhance the ability of national and regional governments, industry, and private citizens to implement and evaluate effective climate change mitigation policies.

  13. Semi-empirical characterization of a greenhouse-effect cascades solar distiller

    Energy Technology Data Exchange (ETDEWEB)

    Khelif, C.; Touati, B. [Station d' Experimentation des Equipements Solaries en Milieu Saharien, Adrar (Algeria)

    2000-02-01

    The analysis in steady state of the different modelizations made on solar flat-plate functioning in low and average temperatures (especially the bridges of surface water) has allowed us to develop a simple linear model. By a swift experimental way, this model is able to approximate the thermal and optical performances of a greenhouse-effect solar distiller. This model has equally served for the verification of the time constant of the system in the same functioning and environment conditions. (author)

  14. Studying the Physical Basis of Global Warming: Thermal Effects of the Interaction between Radiation and Matter and Greenhouse Effect

    Science.gov (United States)

    Besson, Ugo; De Ambrosis, Anna; Mascheretti, Paolo

    2010-01-01

    We present a teaching module dealing with the thermal effects of interaction between radiation and matter, the infrared emission of bodies and the greenhouse effect devoted to university level and teacher education. The module stresses the dependence of the optical properties of materials (transparency, absorptivity and emissivity) on radiation…

  15. Counteracting the climate effects of volcanic eruptions using short-lived greenhouse gases

    Science.gov (United States)

    Fuglestvedt, Jan S.; Samset, Bjørn H.; Shine, Keith P.

    2014-12-01

    A large volcanic eruption might constitute a climate emergency, significantly altering global temperature and precipitation for several years. Major future eruptions will occur, but their size or timing cannot be predicted. We show, for the first time, that it may be possible to counteract these climate effects through deliberate emissions of short-lived greenhouse gases, dampening the abrupt impact of an eruption. We estimate an emission pathway countering a hypothetical eruption 3 times the size of Mount Pinatubo in 1991. We use a global climate model to evaluate global and regional responses to the eruption, with and without counteremissions. We then raise practical, financial, and ethical questions related to such a strategy. Unlike the more commonly discussed geoengineering to mitigate warming from long-lived greenhouse gases, designed emissions to counter temporary cooling would not have the disadvantage of needing to be sustained over long periods. Nevertheless, implementation would still face significant challenges.

  16. [Effects of understory removal on soil greenhouse gas emissions in Carya cathayensis stands].

    Science.gov (United States)

    Liu, Juan; Chen, Xue-shuang; Wu, Jia-sen; Jiang, Pei-kun; Zhou, Guo-mo; Li, Yong-fu

    2015-03-01

    CO2, N2O and CH4 are important greenhouse gases, and soils in forest ecosystems are their important sources. Carya cathayensis is a unique tree species with seeds used for high-grade dry fruit and oil production. Understory vegetation management plays an important role in soil greenhouse gases emission of Carya cathayensis stands. A one-year in situ experiment was conducted to study the effects of understory removal on soil CO2, N2O and CH4 emissions in C. cathayensis plantation by closed static chamber technique and gas chromatography method. Soil CO2 flux had a similar seasonal trend in the understory removal and preservation treatments, which was high in summer and autumn, and low in winter and spring. N2O emission occurred mainly in summer, while CH4 emission showed no seasonal trend. Understory removal significantly decreased soil CO, emission, increased N2O emission and CH4 uptake, but had no significant effect on soil water soluble organic carbon and microbial biomass carbon. The global warming potential of soil greenhouse gases emitted in the understory removal. treatment was 15.12 t CO2-e . hm-2 a-1, which was significantly lower than that in understory preservation treatment (17.04 t CO2-e . hm-2 . a-1).

  17. FETC Programs for Reducing Greenhouse Gas Emissions

    Energy Technology Data Exchange (ETDEWEB)

    Ruether, J.A.

    1998-02-01

    Mark Twain once quipped that everyone talks about the weather but no one does anything about it. With interest in global climate change on the rise, researchers in the fossil-energy sector are feeling the heat to provide new technology to permit continued use of fossil fuels but with reduced emissions of so-called `greenhouse gases.` Three important greenhouse gases, carbon dioxide, methane, and nitrous oxide, are released to the atmosphere in the course of recovering and combusting fossil fuels. Their importance for trapping radiation, called forcing, is in the order given. In this report, we briefly review how greenhouse gases cause forcing and why this has a warming effect on the Earth`s atmosphere. Then we discuss programs underway at FETC that are aimed at reducing emissions of methane and carbon dioxide.

  18. Greenhouse Effect

    Institute of Scientific and Technical Information of China (English)

    刘敬业

    2005-01-01

    2004年12月26日印度洋发生海啸,席卷沿岸12个国家,无数生灵死伤,尸体遍地,疫情潜伏,人们不禁要问:“地球怎么了?人类为什么会遭受如此浩劫?”也许地球正以它特有的方式“证明”着自己的存在。

  19. Effect of reed canary grass cultivation on greenhouse gas emission from peat soil at controlled rewetting

    Directory of Open Access Journals (Sweden)

    S. Karki

    2014-09-01

    Full Text Available Cultivation of bioenergy crops in rewetted peatland (paludiculture is considered as a possible land use option to mitigate greenhouse gas (GHG emissions. However, bioenergy crops like reed canary grass (RCG can have a complex influence on GHG fluxes. Here we determined the effect of RCG cultivation on GHG emission from peatland rewetted to various extents. Mesocosms were manipulated to three different ground water levels (GWL, i.e., 0, −10 and −20 cm below the soil surface in a controlled semi-field facility. Emissions of CO2 (ecosystem respiration, ER, CH4 and N2O from mesocosms with RCG and bare soil were measured at weekly to fortnightly intervals with static chamber techniques for a period of one year. Cultivation of RCG increased both ER and CH4 emissions, but decreased the N2O emissions. The presence of RCG gave rise to 69, 75 and 85% of total ER at −20, −10 and 0 cm GWL, respectively However, this difference was due to decreased soil respiration at the rising GWL as the plant-derived CO2 flux was similar at all three GWL. For methane, 70–95% of the total emission was due to presence of RCG, with the highest contribution at −20 cm GWL. In contrast, cultivation of RCG decreased N2O emission by 33–86% with the major reductions at −10 and −20 cm GWL. In terms of global warming potential, the increase in CH4 emissions due to RCG cultivation was more than off-set by the decrease in N2O emissions at −10 and −20 cm GWL; at 0 cm GWL the CH4 emissions was offset only by 23%. CO2 emissions from ER obviously were the dominant RCG-derived GHG flux, but above-ground biomass yields, and preliminary measurements of gross photosynthetic production, show that ER could be more than balanced due to the uptake of CO2 by RCG. Our results support that RCG cultivation could be a good land use option in terms of mitigating GHG emission from rewetted peatlands, potentially turning these ecosystems into a sink of atmospheric CO2.

  20. The plankton multiplier—positive feedback in the greenhouse

    OpenAIRE

    Woods, John; Barkmann, Wolfgang

    1993-01-01

    The plankton multiplier is a positive feedback mechanism linking the greenhouse effect and biological pump (Woods.J.D., Royal Commission on Environmental Pollution, 1990). As pollution increases the atmospheric concentration of carbon dioxide, the enhanced greenhouse effect induces radiative forcing of the ocean, which diminishes the depth of winter convection, reducing the annual resupply of nutrients to the euphotic zone and therefore the annual primary production. That weakens the biologic...

  1. An example of fingerprint detection of greenhouse climate changes

    Energy Technology Data Exchange (ETDEWEB)

    Karoly, D.J.; Cohen, J.A. [Monash Univ., Clayton, Victoria (Australia); Meehl, G.A. [National Center for Atmospheric Research, Boulder, CO (United States)] [and others

    1994-07-01

    As an example of the technique of fingerprint detection of greenhouse climate change, a multivariate signal or fingerprint of the enhanced greenhouse effect is defined using the zonal mean atmospheric temperature change as a function of height and latitude between equilibrium climate model simulations with control and doubled CO{sub 2} concentrations. This signal is compared with observed atmospheric temperature variations over the period 1963 to 1988 from radiosonde-based global analyses. There is a signiificant increase of this greenhouse signal in the observational data over this period. These results must be treated with caution. Upper air data are available for a short period only, possibly, to be able to resolve any real greenhouse climate change. The greenhouse fingerprint used in this study may not be unique to the enhanced greenhouse effect and may be due to other forcing mechanisms. However, it is shown that the patterns of atmospheric temperature change associated with uniform global increases of sea surface temperature, with El Nino-Southern Oscillation events and with decreases of stratospheric ozone concentrations individually are different from the greenhouse fingerprint used here. 30 refs., 6 figs., 2 tabs.

  2. Effects of nitrogen fertilization on the acidity and salinity of greenhouse soils.

    Science.gov (United States)

    Han, Jiangpei; Shi, Jiachun; Zeng, Lingzao; Xu, Jianming; Wu, Laosheng

    2015-02-01

    A greenhouse pot experiment was conducted to study the effects of conventional nitrogen fertilization on soil acidity and salinity. Three N rates (urea; N0, 0 kg N ha(-1); N1, 600 kg N ha(-1); and N2, 1,200 kg N ha(-1)) were applied in five soils with different greenhouse cultivation years to evaluate soil acidification and salinization rate induced by nitrogen fertilizer in lettuce production. Both soil acidity and salinity increased significantly as N input increased after one season, with pH decrease ranging from 0.45 to 1.06 units and electrolytic conductivity increase from 0.24 to 0.68 mS cm(-1). An estimated 0.92 mol H(+) was produced for 1 mol (NO2 (-) + NO3 (-))-N accumulation in soil. The proton loading from nitrification was 14.3-27.3 and 12.1-58.2 kmol H(+) ha(-1) in the center of Shandong Province under N1 and N2 rate, respectively. However, the proton loading from the uptake of excess bases by lettuces was only 0.3-4.5 % of that from nitrification. Moreover, the release of protons induced the direct release of base cations and accelerated soil salinization. The increase of soil acidity and salinity was attributed to the nitrification of excess N fertilizer. Compared to the proton loading by lettuce, nitrification contributed more to soil acidification in greenhouse soils.

  3. The effect of phosphogypsum on greenhouse gas emissions during cattle manure composting.

    Science.gov (United States)

    Hao, Xiying; Larney, Francis J; Chang, Chi; Travis, Greg R; Nichol, Connie K; Bremer, Eric

    2005-01-01

    Phosphogypsum (PG), a by-product of the phosphate fertilizer industry, reduces N losses when added to composting livestock manure, but its impact on greenhouse gas emissions is unclear. The objective of this research was to assess the effects of PG addition on greenhouse gas emissions during cattle feedlot manure composting. Sand was used as a filler material for comparison. The seven treatments were PG10, PG20, PG30, S10, S20, and S30, representing the rate of PG or sand addition at 10, 20, or 30% of manure dry weight and a check treatment (no PG or sand) with three replications. The manure treatments were composted in open windrows and turned five times during a 134-d period. Addition of PG significantly increased electrical conductivity (EC) and decreased pH in the final compost. Total carbon (TC), total nitrogen (TN), and mineral nitrogen contents in the final composted product were not affected by the addition of PG or sand. From 40 to 54% of initial TC was lost during composting, mostly as CO(2), with CH(4) accounting for <14%. The addition of PG significantly reduced CH(4) emissions, which decreased exponentially with the compost total sulfur (TS) content. The emission of N(2)O accounted for <0.2% of initial TN in the manure, increasing as compost pH decreased from alkaline to near neutral. Based on the total greenhouse gas budget, PG addition reduced greenhouse gas emissions (CO(2)-C equivalent) during composting of livestock manure by at least 58%, primarily due to reduced CH(4) emission.

  4. Effects of meteorite impacts on the atmospheric evolution of Mars.

    Science.gov (United States)

    Pham, Lê Binh San; Karatekin, Ozgür; Dehant, Véronique

    2009-01-01

    Early in its history, Mars probably had a denser atmosphere with sufficient greenhouse gases to sustain the presence of stable liquid water at the surface. Impacts by asteroids and comets would have played a significant role in the evolution of the martian atmosphere, not only by causing atmospheric erosion but also by delivering material and volatiles to the planet. We investigate the atmospheric loss and the delivery of volatiles with an analytical model that takes into account the impact simulation results and the flux of impactors given in the literature. The atmospheric loss and the delivery of volatiles are calculated to obtain the atmospheric pressure evolution. Our results suggest that the impacts alone cannot satisfactorily explain the loss of significant atmospheric mass since the Late Noachian (approximately 3.7-4 Ga). A period with intense bombardment of meteorites could have increased the atmospheric loss; but to explain the loss of a speculative massive atmosphere in the Late Noachian, other factors of atmospheric erosion and replenishment also need to be taken into account.

  5. Industry and greenhouse effect control. A synthesis document of the working group '' industry-greenhouse effect'' of the inter-ministerial mission on the greenhouse effect. Climate change in France in the 21 century?; Industrie et prevention de l'effet de serre. Une note synthese du groupe de travail ''industrie - effet de serre'' de la mission interministerielle sur l'effet de serre. Changement de climat en France au 21. siecle?

    Energy Technology Data Exchange (ETDEWEB)

    Bessemoulin, P. [Meteo France, Dir. de la Climatologie, 75 - Paris (France); Martin, Y.

    2000-04-01

    This document presents two synthesis on the environmental policy concerning the greenhouse effect and the climatic changes. The first one presents the results of the five working groups, constituted by the inter-ministerial Mission on the greenhouse effect. These following groups are supposed to help the Mission to define the french position concerning the international negotiations: energy production and greenhouse effect, industry and greenhouse effect, transportation system and greenhouse effect, residential and tertiary sectors and greenhouse effect, agriculture wastes and greenhouse effect. The second one deals with the potential impacts of the climatic change in France. (A.L.B.)

  6. 沿海不同棚架构型温度变化规律及西瓜种植研究%Temperature Change Rules of Different Steel Greenhouses and Their Effects on Watermelon Cultivation

    Institute of Scientific and Technical Information of China (English)

    孙兴祥; 林红梅

    2013-01-01

    In the paper, we studied the temperature change rules of different types of steel greenhouses and their effects on the growth and development of watermelon. The results showed that, as the greenhouse depth-width ratio became larger, the atmospheric temperature in the greenhouses increased and reduced quicker, and the difference of the day and night earth temperature became larger, indicating their better maintaining effects on atmospheric temperature but worse maintaining effects on earth temperature. In the watermelon cultivation in coastal areas of Jiangsu, the greenhouse A4 possessed the best temperature maintaining effects and comprehensive evaluation, and the structure of greenhouse A4 was as follows:the centre-height of the outer steel greenhouse, inner steel greenhouse and small arch shed were 2.5 m, 2.4 m and 0.8 m, with their width were 7.0 m, 6.6 m and 2.0 m, respectively. The greenhouse A1 was more affordable, and its structure was as follows:the centre-height of the outer steel greenhouse, inner steel greenhouse and small arch shed were 1.8 m, 1.7 m and 0.8 m, with their width were 5.0 m, 4.6 m and 2.0 m, respectively.%  研究了不同棚型内的温度变化,以及其对西瓜生长和发育的影响.研究结果表明,棚高宽比大,棚内气温升高快,降低也快,日夜气温温差大,日夜地温温差大,气温保温性差,但地温保温性好;沿海地区大棚西瓜种植采用A4型棚(外棚顶高2.5 m、宽7.0 m,内棚顶高2.4 m、宽6.6 m,小棚顶高0.8 m、宽2.0 m)效果好,采用A1型棚(外棚顶高1.8 m、宽5.0 m,内棚顶高1.7 m、宽4.6 m,小棚顶高0.8 m、宽2.0 m)较为经济.

  7. Assessment the Effects of Temperature and Humidity Control in Greenhouse Cucumber Productions in Jiroft and Kahnooj Region

    Directory of Open Access Journals (Sweden)

    D Momeni

    2012-05-01

    Full Text Available Temperature and humidity are two important parameters affecting the quality and quantity of greenhouse products so two double greenhouses were manufactured in 3.5, 40 and 11 m in height, length and width respectively in agricultural research center of jiroft and kahnooj to study these effects. Both of greenhouses are similar in materials, final height, gutter height, covering and field operation but in one of them one heating system, two ventilation fans and one wooden pad were assembled and temperature and humidity besides yield were registered in both of them. The results showed that temperature changing trend inside and outside of the unheated greenhouse were in same phase and this isn't suitable in cold night so the greenhouse with heating system had more yield and picking cucumber fruit numbers than another. Therefore it is necessary to be heated by artificial systems. Because of rapid relative humidity changing in outside of greenhouse in the end of the season, the efficiency of fan and pads cooling system is so low then using of evaporating cooling systems such as fans and pad wasn't proposed and recommend to optimize the temperature by ventilation and shading the greenhouse and in hot days production will be cut.

  8. Climate and site management as driving factors for the atmospheric greenhouse gas exchange of a restored wetland

    DEFF Research Database (Denmark)

    Herbst, Mathias; Friborg, Thomas; Schelde, K.;

    2013-01-01

    and management activities were used to explain the large inter-annual variations in the full atmospheric GHG budget of the wetland. The largest impact on the annual GHG fluxes, eventually defining their sign, came from site management through changes in grazing duration and animal stocking density. These changes...

  9. Engineering concepts for inflatable Mars surface greenhouses.

    Science.gov (United States)

    Hublitz, I; Henninger, D L; Drake, B G; Eckart, P

    2004-01-01

    A major challenge of designing a bioregenerative life support system for Mars is the reduction of the mass, volume, power, thermal and crew-time requirements. Structural mass of the greenhouse could be saved by operating the greenhouse at low atmospheric pressure. This paper investigates the feasibility of this concept. The method of equivalent system mass is used to compare greenhouses operated at high atmospheric pressure to greenhouses operated at low pressure for three different lighting methods: natural, artificial and hybrid lighting.

  10. Effects of Nitrogen Fertilization of Boreal Forest Land on Greenhouse Gas Flows

    Science.gov (United States)

    Gustavsson, L.; Sathre, R. C.

    2011-12-01

    Forest growth on mineral soils in boreal regions is often limited by a low availability of nitrogen (N), and fertilization has shown particular promise in increasing yields in productive boreal forests. In this study we analyze the greenhouse gas (GHG) implications of increasing forest biomass production through N fertilization and using the increased production for bioenergy and biomaterials in place of non-renewable fuels and materials. We begin with a stand-level analysis of the radiative forcing implications of forest fertilization and biomass substitution, with explicit consideration of the temporal patterns of GHG emissions to and removals from the atmosphere. We model and compare the production and use of biomass from a hectare of fertilized and non-fertilized forest land in northern Sweden. We calculate the annual net emissions of CO2, N2O and CH4 for each system, over a 225-year period with 1-year time steps. We calculate the annual atmospheric concentration decay of each of these emissions, and calculate the resulting annual changes in instantaneous and cumulative radiative forcing. We find that forest fertilization can significantly increase biomass production, which increases the potential for material and energy substitution. The average carbon stock in tree biomass, forest soils and wood products all increase when fertilization is used. The additional GHG emissions due to fertilizer production and application are small compared to increases in carbon stock and substitution benefits. By the end of the 225-year simulation period, the cumulative radiative forcing reduction of the fertilized stand is over twice that of the non-fertilized stand. We then consider a steady-state landscape-level scenario where 10% of Swedish forest land is fertilized. We estimate the primary energy use and GHG emissions from forest management including production and application of N and NPK fertilizers. Based on modelled growth response, we then estimate the net GHG benefits

  11. Effect of elevated atmospheric CO2 on carbon allocation patterns in Eriphorum vaginatum

    Science.gov (United States)

    Strom, L.

    2013-12-01

    Greenhouse gases of particular importance to the human induced greenhouse effect are, e.g., CO2 and CH4. Natural and agricultural wetlands together contribute with over 40 % of the annual atmospheric emissions of CH4 and are, therefore, considered to be the largest single contributor of this gas to the troposphere. There is a growing concern that increasing atmospheric concentrations of CO2 will stimulate CH4 production and emission from wetland ecosystems, resulting in feedback mechanisms that in future will increase the radiative forcing of these ecosystems. The aim of this study was to elucidate the effect of elevated atmospheric CO2 on fluxes of CO2 and CH4, biomass allocation patterns and amount of labile substrates (i.e. low molecular weight organic acids, OAs) for CH4 production in the root vicinity of Eriophorum vaginatum. Eriophorum cores and plants were collected at Fäjemyr, a temperate ombrotrophic bog situated in the south of Sweden. These were cultivated under controlled environmental conditions in an atmosphere of 390 or 800 ppm of CO2 (n=5 per treatment). After a one month development period gas fluxes were measured twice per week over one month using a Fourier Transform Infrared spectrometer (Gasmet Dx-4030) and OAs using a liquid chromatography-ionspray tandem mass spectrometry system (Dionex ICS-2500 and Applied Biosystems 2000 Q-Trap triple quadrupole MS). The results clearly show that elevated CO2 significantly affects all measured parts of the carbon cycle. Greenhouse gas fluxes were significantly (repeated measures test) higher under elevated CO2 conditions, NEE p leaves, roots and concentration of OAs around the roots of plants, p = 0.045, p = 0 = 0.045 and p = 0.045 respectively (Kruskal wallis 1-way anova). The study shows higher CH4 emissions under elevated CO2 and that this may be due to a priming effect, due to input of fresh labile-C via living roots and possibly higher biomass. However the concern that elevated atmospheric

  12. Global change could amplify fire effects on soil greenhouse gas emissions.

    Directory of Open Access Journals (Sweden)

    Audrey Niboyet

    Full Text Available BACKGROUND: Little is known about the combined impacts of global environmental changes and ecological disturbances on ecosystem functioning, even though such combined impacts might play critical roles in shaping ecosystem processes that can in turn feed back to climate change, such as soil emissions of greenhouse gases. METHODOLOGY/PRINCIPAL FINDINGS: We took advantage of an accidental, low-severity wildfire that burned part of a long-term global change experiment to investigate the interactive effects of a fire disturbance and increases in CO(2 concentration, precipitation and nitrogen supply on soil nitrous oxide (N(2O emissions in a grassland ecosystem. We examined the responses of soil N(2O emissions, as well as the responses of the two main microbial processes contributing to soil N(2O production--nitrification and denitrification--and of their main drivers. We show that the fire disturbance greatly increased soil N(2O emissions over a three-year period, and that elevated CO(2 and enhanced nitrogen supply amplified fire effects on soil N(2O emissions: emissions increased by a factor of two with fire alone and by a factor of six under the combined influence of fire, elevated CO(2 and nitrogen. We also provide evidence that this response was caused by increased microbial denitrification, resulting from increased soil moisture and soil carbon and nitrogen availability in the burned and fertilized plots. CONCLUSIONS/SIGNIFICANCE: Our results indicate that the combined effects of fire and global environmental changes can exceed their effects in isolation, thereby creating unexpected feedbacks to soil greenhouse gas emissions. These findings highlight the need to further explore the impacts of ecological disturbances on ecosystem functioning in the context of global change if we wish to be able to model future soil greenhouse gas emissions with greater confidence.

  13. High chance that current atmospheric greenhouse concentrations commit to warmings greater than 1.5 °C over land.

    Science.gov (United States)

    Huntingford, Chris; Mercado, Lina M

    2016-07-27

    The recent Paris UNFCCC climate meeting discussed the possibility of limiting global warming to 2 °C since pre-industrial times, or possibly even 1.5 °C, which would require major future emissions reductions. However, even if climate is stabilised at current atmospheric greenhouse gas (GHG) concentrations, those warming targets would almost certainly be surpassed in the context of mean temperature increases over land only. The reason for this is two-fold. First, current transient warming lags significantly below equilibrium or "committed" warming. Second, almost all climate models indicate warming rates over land are much higher than those for the oceans. We demonstrate this potential for high eventual temperatures over land, even for contemporary GHG levels, using a large set of climate models and for which climate sensitivities are known. Such additional land warming has implications for impacts on terrestrial ecosystems and human well-being. This suggests that even if massive and near-immediate emissions reductions occur such that atmospheric GHGs increase further by only small amounts, careful planning is needed by society to prepare for higher land temperatures in an eventual equilibrium climatic state.

  14. High chance that current atmospheric greenhouse concentrations commit to warmings greater than 1.5 °C over land

    Science.gov (United States)

    Huntingford, Chris; Mercado, Lina M.

    2016-07-01

    The recent Paris UNFCCC climate meeting discussed the possibility of limiting global warming to 2 °C since pre-industrial times, or possibly even 1.5 °C, which would require major future emissions reductions. However, even if climate is stabilised at current atmospheric greenhouse gas (GHG) concentrations, those warming targets would almost certainly be surpassed in the context of mean temperature increases over land only. The reason for this is two-fold. First, current transient warming lags significantly below equilibrium or “committed” warming. Second, almost all climate models indicate warming rates over land are much higher than those for the oceans. We demonstrate this potential for high eventual temperatures over land, even for contemporary GHG levels, using a large set of climate models and for which climate sensitivities are known. Such additional land warming has implications for impacts on terrestrial ecosystems and human well-being. This suggests that even if massive and near-immediate emissions reductions occur such that atmospheric GHGs increase further by only small amounts, careful planning is needed by society to prepare for higher land temperatures in an eventual equilibrium climatic state.

  15. Conceptual approaches to innovative energy saving technologies and reducing greenhouse effect

    Energy Technology Data Exchange (ETDEWEB)

    Buyadgie, Dmytro; Sechenyh, Vitaliy; Buyadgie, Olexiy; Nichenko, Sergii; Vasil' ev, Igor

    2010-09-15

    The study attempts a comprehensive overview of the effects of human activities and proposes technical solutions for compensation of human anthropogenic intervention. Attention is focused on energy consumption optimization and reduction of harmful emissions at current stage of civilization development. Natural sources of energy and their associated greenhouse gases (GHG) emissions are considered in the paper along with the existed approaches to energy utilization, its merits and demerits. The role of heat-utilizing thermotransformers in reduction of thermal release and GHG emissions is specified. The examples of energy efficient technologies, based on application of jet devices, are presented in the study.

  16. Effects of cover properties, ventilation rate and crop leaf area on tropical greenhouse climate

    NARCIS (Netherlands)

    Impron, I.; Hemming, S.; Bot, G.P.A.

    2008-01-01

    Experimental results and validation of a simple greenhouse climate model are analysed according to data sets from six prototype greenhouses with three different plastics (reference N0, and two levels of near-infrared reflecting pigments N1 and N2); two ratios of ventilation openings to greenhouse co

  17. Compensation for atmospheric effects in LANDSAT data

    Science.gov (United States)

    Lambeck, P. F.; Potter, J. F. (Principal Investigator)

    1979-01-01

    Preprocessing algorithms were developed to remove or reduce the variations in multispectral data caused by variations in Sun angle and by changes in the atmospheric aerosol and water vapor levels. The two most significant algorithms developed by using mathematical models to define interrelations between the required multiplicative and additive correction factors so that just a few statistical characteristics of a LANDSAT distribution model would be sufficient to drive the mathematical model and to calculate the preprocessing corrections are examined. These are the atmospheric correction (ATCOR) computer program and the XSTAR haze correction algorithm. Neither the ATCOR nor the XSTAR algorithm provides an explicit compensation for the effects of changing LANDSAT view angle. Development efforts are underway to address this aspect of the preprocessing problem.

  18. Effects of Different Regulatory Methods on Improvement of Greenhouse Saline Soils, Tomato Quality, and Yield

    Directory of Open Access Journals (Sweden)

    Hou Maomao

    2014-01-01

    Full Text Available To identify effective regulatory methods scheduling with the compromise between the soil desalination and the improvement of tomato quality and yield, a 3-year field experiment was conducted to evaluate and compare the effect of straw mulching and soil structure conditioner and water-retaining agent on greenhouse saline soils, tomato quality, and yield. A higher salt removing rate of 80.72% in plough layer with straw mulching was obtained based on the observation of salt mass fraction in 0~20 cm soil layer before and after the experiment. Salts were also found to move gradually to the deeper soil layer with time. Straw mulching enhanced the content of soil organic matter significantly and was conductive to reserve soil available N, P, and K, while available P and K in soils of plough layer with soil structure conditioner decreased obviously; thus a greater usage of P fertilizer and K fertilizer was needed when applying soil structure conditioner. Considering the evaluation indexes including tomato quality, yield, and desalination effects of different regulatory methods, straw mulching was recommended as the main regulatory method to improve greenhouse saline soils in south China. Soil structure conditioner was the suboptimal method, which could be applied in concert with straw mulching.

  19. Surplus thermal energy model of greenhouses and coefficient analysis for effective utilization

    Directory of Open Access Journals (Sweden)

    Seung-Hwan Yang

    2016-03-01

    Full Text Available If a greenhouse in the temperate and subtropical regions is maintained in a closed condition, the indoor temperature commonly exceeds that required for optimal plant growth, even in the cold season. This study considered this excess energy as surplus thermal energy (STE, which can be recovered, stored and used when heating is necessary. To use the STE economically and effectively, the amount of STE must be estimated before designing a utilization system. Therefore, this study proposed an STE model using energy balance equations for the three steps of the STE generation process. The coefficients in the model were determined by the results of previous research and experiments using the test greenhouse. The proposed STE model produced monthly errors of 17.9%, 10.4% and 7.4% for December, January and February, respectively. Furthermore, the effects of the coefficients on the model accuracy were revealed by the estimation error assessment and linear regression analysis through fixing dynamic coefficients. A sensitivity analysis of the model coefficients indicated that the coefficients have to be determined carefully. This study also provides effective ways to increase the amount of STE.

  20. Surplus thermal energy model of greenhouses and coefficient analysis for effective utilization

    Energy Technology Data Exchange (ETDEWEB)

    Yang, S.H.; Son, J.E.; Lee, S.D.; Cho, S.I.; Ashtiani-Araghi, A.; Rhee, J.Y.

    2016-11-01

    If a greenhouse in the temperate and subtropical regions is maintained in a closed condition, the indoor temperature commonly exceeds that required for optimal plant growth, even in the cold season. This study considered this excess energy as surplus thermal energy (STE), which can be recovered, stored and used when heating is necessary. To use the STE economically and effectively, the amount of STE must be estimated before designing a utilization system. Therefore, this study proposed an STE model using energy balance equations for the three steps of the STE generation process. The coefficients in the model were determined by the results of previous research and experiments using the test greenhouse. The proposed STE model produced monthly errors of 17.9%, 10.4% and 7.4% for December, January and February, respectively. Furthermore, the effects of the coefficients on the model accuracy were revealed by the estimation error assessment and linear regression analysis through fixing dynamic coefficients. A sensitivity analysis of the model coefficients indicated that the coefficients have to be determined carefully. This study also provides effective ways to increase the amount of STE. (Author)

  1. Effects of Bioinsecticides in Control of Greenhouse Whitefly (Trialeurodes vaporariorum Westwood on Tomato

    Directory of Open Access Journals (Sweden)

    Dejan Marčić

    2011-01-01

    Full Text Available The effects of commercial products of entomopathogenic fungus Beauveria bassiana(Naturalis; 0.1%, 0.2% and 0.3%, azadirachtin (NeemAzal T/S; 1% and 2% and oxymatrin(KingBo; 0.1% and 0.2% in the control of greenhouse whitefly (Trialeurodes vaporariorumWestwood on tomato were tested in plastic covered greenhouse. The effects of the bioinsecticides,applied twice at five-day interval, were compared to effects of abamectin (AbastateEW; 0.075% and thiamethoxam (Actara 25-WG; 0.05%. Tested bioinsecticides reducedthe number of larvae by 82-97% (Naturalis, 90-99% (NeemAzal T/S and 90-96% (KingBo,with the efficacy of >96% according to Henderson-Tilton, in the assessment 16 days aftertreatment. In the same assessment, achieved percentages in adults reduction and efficacyamounted 24-89% and 67-95% (Naturalis, 85-93% and 93-97% (NeemAzal T/S, 86-96%and 94-98% (KingBo. Percentages of abundance reduction and efficacy after treatment withAbastate EW were 31% and 88% (larvae and 64% and 84% (adults, while after treatmentwith Actara 25-WG they amounted 96% and 99% (larvae and 83% and 92% (adults. The resultsobtained show that NeemAzal T/S, Naturalis and KingBo can be an efficient alternativeto current insecticides in control of T. vaporariorum populations.

  2. Effect of Elevated CO2 in Different Fertilizer Conditions on Physiological Traits in Lemon Balm (Melissa officinalis at Greenhouse

    Directory of Open Access Journals (Sweden)

    M Shoor

    2012-07-01

    Full Text Available Increasing atmospheric CO2 concentrations and nutrients supply are generally expected to enhance photosynthesis and growth of crops as a result considerably increase yields. The present study aims to investigate effects of elevated CO2 and different fertilizer conditions on physiological traits in Lemon balm. A factorial experiment was conducted based on completely randomized design with three replications and nine treatments at the greenhouse in 2010. The experiment factors were included three CO2 concentrations (380, 700 and 1050 ppm and three kinds of conditions fertilizer (no fertilizer, manure fertilizer and nitrogen fertilizer. The results indicated that increasing of CO2 from 380 to 1050 ppm led to improve in leaf area, plant height, relative growth ratio, total dry matter and final yield of individual plant. The highest and the lowest amount of measured traits related to with and without nitrogen fertilizer, respectively. Impact of elevated CO2 in conjunction with nitrogen and manure fertilizers increased. These effects were more on total dry matter and final yield than other growth indices. Therefore, it can be concluded that, whereas increase of temperature caused by rising CO2 is not considered or there is not any limitation for resources, CO2 enrichment will be improved lemon balm production.

  3. The effect of different methods of seed bed preparation on greenhouse cucumber yield and yield components

    Directory of Open Access Journals (Sweden)

    D. Momeni

    2010-12-01

    Full Text Available To investigate the effects of different methods of seed bed preparation on yield of greenhouse cucumber, a two-year long experiment was conducted as a randomized complete block design with four replications in Jiroft from 2004. Different methods of seed bed preparation were as follows: 1 ridge with 20 cm height and 50 cm width and 2 plant rows with 40 cm distance, 2 furrow with 20 cm depth and 50 cm width and 2 plant rows inside, with 40 cm distance, and 3 planting on flat area with 40 cm distance. The results showed that the effect of planting bed on yield of greenhouse cucumber was significant. Furrow and flat area increased yield significantly, compared to the ridge treatment. Analysis of yield components such as plant height, number of pickling fruits, number of leaves, photosynthetic area and number of flowers showed that they are all correlated with fruit yield. The number of pickling fruits was significantly more in furrow and flat area than in ridge treatment. The height of cucumber plants on flat bed was significantly higher than that of the other treatments. The number of leaves and photosynthetic area of plants on flat bed were significantly greater than those in the other treatments. The least dead plants due to fungi disease were observed in ridge treatment. In view of yield and its components under the condition of this experiment, it can be concluded that flat area and furrow treatments are better than ridge treatment.

  4. Sludge thermal oxidation processes: mineral recycling, energy impact, and greenhouse effect gases release

    Energy Technology Data Exchange (ETDEWEB)

    Guibelin, Eric

    2003-07-01

    Different treatment routes have been studied for a mixed sludge: the conventional agricultural use is compared with the thermal oxidation processes, including incineration (in gaseous phase) and wet air oxidation (in liquid phase). The interest of a sludge digestion prior to the final treatment has been also considered according to the two major criteria, which are the fossil energy utilisation and the greenhouse effect gases (CO{sub 2}, CH{sub 4}, N{sub 2}O) release. Thermal energy has to be recovered on thermal processes to make these processes environmentally friendly, otherwise their main interest is to extract or destroy micropollutants and pathogens from the carbon cycle. In case of continuous energy recovery, incineration can produce more energy than it consumes. Digestion is especially interesting for agriculture: according to these two schemes, the energy final balance can also be in excess. As to wet air oxidation, it is probably one of the best way to minimize greenhouse effect gases emission. (author)

  5. A Greenhouse Assay on the Effect of Applied Urea Amount on the Rhizospheric Soil Bacterial Communities.

    Science.gov (United States)

    Shang, Shuanghua; Yi, Yanli

    2015-12-01

    The rhizospheric bacteria play key role in plant nutrition and growth promotion. The effects of increased nitrogen inputs on plant rhizospheric soils also have impacted on whole soil microbial communities. In this study, we analyzed the effects of applied nitrogen (urea) on rhizospheric bacterial composition and diversity in a greenhouse assay using the high-throughput sequencing technique. To explore the environmental factors driving the abundance, diversity and composition of soil bacterial communities, the relationship between soil variables and the bacterial communities were also analyzed using the mantel test as well as the redundancy analysis. The results revealed significant bacterial diversity changes at different amounts of applied urea, especially between the control treatment and the N fertilized treatments. Mantel tests showed that the bacterial communities were significantly correlated with the soil nitrate nitrogen, available nitrogen, soil pH, ammonium nitrogen and total organic carbon. The present study deepened the understanding about the rhizospheric soil microbial communities under different amounts of applied urea in greenhouse conditions, and our work revealed the environmental factors affecting the abundance, diversity and composition of rhizospheric bacterial communities.

  6. Investigation into the emission of greenhouse effect gases; Onshitsu koka gas no haishutsu ni kansuru chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    The paper grasped the situation of greenhouse effect gas emissions of advanced countries based on the reports from them. The advanced countries which concluded the U.N. Framework Convention on Climate Change (OECD member countries, the former U.S.S.R., and East European countries) are to be reported to the office concerned with work for the framework the situation of their greenhouse effect gas emissions according to the obligation of the framework. In and after April 1997, they made the second report. The paper summarized changes in emission amount, the future trend, and the policies/measures mainly taken of nine countries which have already presented the second report (the U.S., the U.K., Germany, Holland, Italy, Norway, Sweden, Finland, and New Zealand) and one country (Russia) which has made only the first report. Moreover, the literature was collected and summed up concerning the mechanism and coefficients of the emission of nitrous oxide and methane. The collected literature was classified into all fields/plural number of fields, energy relation, industrial process relation, relation with the use of organic solvent and other products, agricultural relation, relation with changes in land use and forests, and waste relation. 4 figs., 228 tabs.

  7. Empirical Quantification of the Runaway Greenhouse Limit on Earth

    Science.gov (United States)

    Goldblatt, C.; Dewey, M. C.

    2015-12-01

    There have been many modeling studies of the runaway greenhouse effect and the conditions required to produce one on an Earth-like planet, however these models have not been verified with empirical evidence. It has been suggested that the Earth's tropics may be near a state of localized runaway greenhouse, meaning the surface temperature and atmospheric composition in those areas could cause runaway greenhouse, were it not for the tempering effects of meridional heat transport and circulation (Pierrehumbert, 1995). Using the assumption that some areas of the Earth's tropics may be under these conditions, this study uses measurements of the atmospheric properties, surface properties, and radiation budgets of these areas to quantify a radiation limit for runaway greenhouse on Earth, by analyzing the dependence of outgoing longwave radiation (OLR) at the top of the atmosphere on surface temperature and total column water vapour. An upper limit on OLR for clear-sky conditions was found between 289.8 W/m2 and 292.2 W/m2, which occurred at surface temperatures near 300K. For surface temperatures above this threshold, total column water vapour increased, but OLR initially decreased and then remained relatively constant, between 273.6 W/m2 and 279.7 W/m2. These limits are in good agreement with recent modeling results (Goldblatt et al., 2013), supporting the idea that some of the Earth's tropics may be in localized runaway greenhouse, and that radiation limits for runaway greenhouse on Earth can be empirically derived. This research was done as part of Maura Dewey's undergraduate honours thesis at the University of Victoria. Refs: Robert T. Pierrehumbert. Thermostats, radiator fins, and the local runaway greenhouse. Journal of Atmospheric Sciences, 52(10):1784-1806, 1995. Colin Goldblatt, Tyler D. Robinson, Kevin J. Zahnle, and David Crisp. Low simulated radiation limit for runaway greenhouse climates. Nature Geoscience, 6:661-667, 2013.

  8. Part I. Development of a concept inventory addressing students' beliefs and reasoning difficulties regarding the greenhouse effect, Part II. Distribution of chlorine measured by the Mars Odyssey Gamma Ray Spectrometer

    Science.gov (United States)

    Keller, John Michael

    This work presents two research efforts, one involving planetary science education research and a second involving the surface composition of Mars. In the former, student beliefs and reasoning difficulties associated with the greenhouse effect were elicited through student interviews and written survey responses from >900 US undergraduate non-science majors. This guided the development of the Greenhouse Effect Concept Inventory (GECI), an educational research tool designed to assess pre- and post-instruction conceptual understanding of the greenhouse effect. Three versions of this multiple-choice instrument were administered to >2,500 undergraduates as part of the development and validation process. In contrast to previous research efforts regarding causes, consequences, and solutions to the enhanced greenhouse effect, the GECI focuses primarily on the physics of energy flow through Earth's atmosphere. The GECI is offered to the science education community as a research tool for assessing instructional strategies on this topic. It was confirmed that the study population subscribes to several previously identified beliefs. These include correct understandings that carbon dioxide is an important greenhouse gas and the greenhouse effect increases planetary surface temperatures. Students also commonly associate the greenhouse effect with increased penetration of sunlight into and trapping of solar energy in the atmosphere. Students intermix concepts associated with the greenhouse effect, global warming, and ozone depletion. Reinforcing the latter concept, a majority believe that the Sun radiates most of its energy as ultraviolet light. Students also describe inaccurate and incomplete trapping models, which include permanent trapping, trapping through reflection, and trapping of gases and pollution. Another reasoning difficulty involves the idea that Earth's surface radiates energy primarily during the nighttime. The second research effort describes the distribution of

  9. Greener greenhouses

    Energy Technology Data Exchange (ETDEWEB)

    Paksoy, Halime; Turgut, Bekir; Beyhan, Beyza; Dasgan, H. Yildiz; Evliya, Hunay; Abak, Kazim; Bozdag, Saziye

    2010-09-15

    Agricultural greenhouses are solution to the increased demand for higher production yields, facilitating off season cultivation and allowing the growth of certain varieties in areas where it was not possible earlier. Heating and/or cooling system, required to maintain the inside micro-climate in greenhouses mostly rely on fossil fuels and/or electricity. This paper aims to discuss the 'greener' solutions for heating and cooling systems of greenhouses based on different thermal energy storage concepts. Results from a greenhouse Aquifer Thermal Energy Storage (ATES) application in Turkey producing tomatoes with zero fossil fuels and up to 40% higher yield are presented.

  10. Effects of land use intensity on the full greenhouse gas balance in an Atlantic peat bog

    Directory of Open Access Journals (Sweden)

    S. Beetz

    2012-06-01

    Full Text Available The assessment of emission factors for many peatlands is difficult, and reliable data on the exchange of carbon dioxide (CO2, methane (CH4 and nitrous oxide (N2O between soil and atmosphere of these areas is particularly scarce. Reasons for this are the multitude of soil and land use combinations that control greenhouse gas exchange and the high effort associated with data acquisition.

    We investigated the greenhouse gas exchange of a peat bog restoration sequence over a period of 2 yr (July 2007–June 2009 in an Atlantic raised bog in Northwest Germany. We set up three sites representing different land use intensities: intensive grassland (mineral fertilizer, cattle manure and 4–5 cuts per year; extensive grassland (no fertilizer or manure, maximal 1 cutting per year; near-natural peat bog (almost no anthropogenic influence.

    We obtained seasonal and annual estimates of greenhouse gas exchange based on closed chamber measurements. CH4 and N2O fluxes were recorded bi-weekly, CO2 NEE determinations were carried out 3–4 weekly. To get annual sums the CH4 and N2O fluxes were interpolated linearly while NEE was modelled. The intensive grassland site emitted 548 ± 169 g CO2-C m−2 in the first and 817 ± 140 g CO2-C m−2 in the second year. The extensive grassland site showed a slight uptake in the first year (−148 ± 143 g CO2-C m−2, and a small emission of 88 ± 146 g CO2-C m−2 in the second year. In contrast to these agriculturally used sites, the near-natural site took up CO2-C in both years (−8 ± 68 g CO2-C m−2 and −127 ± 53 g CO2-C m−2. Under consideration of N2O and CH4 exchange, the total average greenhouse warming potential (GWP for 2008 amounts to 441

  11. Theoretical Investigation of Mono- and Di-Chloro-Substitient Effects on the Insulation and Greenhouse Properties of Octafluorocyclobutane

    Directory of Open Access Journals (Sweden)

    Lin Cheng

    2016-12-01

    Full Text Available Octafluorocyclobutane, c-C4F8, and its derivatives are regarded as promising replacements of insulation gaseous SF6, which are currently widely used in electric equipment but suffer greatly from its greenhouse effect. Based on the recent finding that the dielectric and thermodynamics properties of insulating gases are greatly dependent on the molecule’s microscopic electronic and vibrational parameters, in this work, we use density functional theory (DFT to study the molecular structures, electron affinities, and IR-active vibrational frequencies as well as thermodynamic properties for c-C4F8 and a series of mono-, di-substituted c-C4F8 compounds. It is shown that DFT calculation of perfluoro-compounds is sensitive to the chosen functional. Although all chloro-substituted c-C4F8 molecules are found to have much larger electron affinities, only part of them have less IR intensity in the atmospheric IR window than c-C4F8. Such a study provides useful guideline for the pre-screening search for new insulation gases via electronic structure calculations.

  12. Effect of Atmospheric Ions on Interfacial Water

    Directory of Open Access Journals (Sweden)

    Chien-Chang Kurt Kung

    2014-11-01

    Full Text Available The effect of atmospheric positivity on the electrical properties of interfacial water was explored. Interfacial, or exclusion zone (EZ water was created in the standard way, next to a sheet of Nafion placed horizontally at the bottom of a water-filled chamber. Positive atmospheric ions were created from a high voltage source placed above the chamber. Electrical potential distribution in the interfacial water was measured using microelectrodes. We found that beyond a threshold, the positive ions diminished the magnitude of the negative electrical potential in the interfacial water, sometimes even turning it to positive. Additionally, positive ions produced by an air conditioner were observed to generate similar effects; i.e., the electrical potential shifted in the positive direction but returned to negative when the air conditioner stopped blowing. Sometimes, the effect of the positive ions from the air conditioner was strong enough to destroy the structure of interfacial water by turning the potential decidedly positive. Thus, positive air ions can compromise interfacial water negativity and may explain the known negative impact of positive ions on health.

  13. Effect of phlogopite size on potassium supply to plant under greenhouse conditions

    Directory of Open Access Journals (Sweden)

    M. S. Mousavi Dastenaei

    2013-10-01

    Full Text Available Micaceous minerals, including phlogopite, are frequently used as the growth medium with different commercial names for greenhouse plants. The objective of this investigation was to understand the effect of phlogopite size on the release and supply of potassium (K under greenhouse conditions. A pot experiment was carried out with a completely randomized design using factorial arrangement and 3 replications. Treatments consisted of 4 particle sizes of phlogopite and a control, as well as 2 types of nutrient solution (with/without K. Alfalfa was the test plant which was grown on a mixture of sand and phlogopite for a period of 6 months. During the growing period, shoot was harvested 4 times and the root was collected at the end of the experiment and their K concentration was measured. Under the K-free nutrient solution, the K concentration and total uptake was highest in pots containing the smallest phlogopite size. As the size of mineral decreases, the conditions for mineral weathering seem to become more favorable and therefore, mica releases its K more quickly. Therefore, if the long term K supply is important, coarse-sized phlogopite should be used. In contrast, fine-grained phlogopite is suitable when K is to be supplied very quickly.

  14. High salinity effect on bioremediation of pretreated pesticide lixiviates from greenhouses.

    Science.gov (United States)

    Micó, María M; González, Óscar; Bacardit, Jordi; Malfeito, Jorge; Sans, Carme

    2015-01-01

    Hydroponics culture greenhouses usually work in closed and semi-closed irrigation systems for nutrients and water-saving purposes. Photo-Fenton reaction has been revealed as an efficient way to depollute that kind of recycled effluents containing pesticides, even for high salinity concentrations. However, the inefficacy of organic matter chemical depletion imposes the use of a subsequent treatment. This work proposes the suitability of an integration of advanced oxidation process with a subsequent bioreactor to treat greenhouse lixiviates effluents at high or extremely high conductivity (salts concentration: up to 42 g L⁻¹). As a first step in this study, the performance of a series of sequencing batch reactors was monitored in order to check the biocompatibility of photo-Fenton pretreated effluents depending on their salinity content. In the second step, those same pretreated effluents were loaded to a biofiltration column filled with expanded clay. Finally, bacterial 16S rRNA gene sequencing was carried out to analyse microbial diversity of the biomass developed in the column. Results stated that the chemical-biological coupled system is effective for the treatment of water effluents containing pesticides. The integrated system is able to deplete more than 80% of the organic load, even under extremely high salinity.

  15. Effects of plant size, temperature, and light intensity on flowering of Phalaenopsis hybrids in Mediterranean greenhouses.

    Science.gov (United States)

    Paradiso, Roberta; De Pascale, Stefania

    2014-01-01

    Mediterranean greenhouses for cultivation of Phalaenopsis orchids reproduce the warm, humid, and shaded environment of tropical underbrush. Heating represents the highest production cost, due to the high thermal requirements and the long unproductive phase of juvenility, in which plants attain the critical size for flowering. Our researches aimed to investigate the effect of plant size, temperature, and light intensity, during the phase of flower induction, on flowering of modern genotypes selected for Mediterranean greenhouses. Three experiments were carried out to compare (i) plant size: reduced size versus size considered optimal for flowering (hybrids "Sogo Yukidian," "Chain Xen Diamond," and "Pinlong"); (ii) temperature: moderate reduction of temperature versus standard thermal regime (hybrid "Premium"); (iii) light intensity: supplemental lighting versus reference light intensity (hybrid "Premium"). The premature exposure of plants to the inductive treatment delayed the beginning of flowering and reduced the flower stem quality, in all the tested hybrids. In "Premium," the lower temperature did not affect flowering earliness and commercial quality of flower stems compared to the standard regime, whereas it promoted stem branching. In the same hybrid, supplemental lighting anticipated flowering and promoted the emission of the second stem and the stem branching, compared to the reference light regime.

  16. EFFECT OF SOIL SOLARIZATION ON THERMAL REGIME OF PLASTIC GREENHOUSE SOIL

    Directory of Open Access Journals (Sweden)

    Nereu Augusto Streck

    1994-01-01

    Full Text Available SUMMARY Temperature modification in soil of plastic greenhouse caused by solarization was measured during the summer in the Subtropical Central Region of the Rio Grande do Sul State, Brazil. The experiment was carried out in a 10m x 25m greenhouse covered with low density transparent polyethylene (PE. Four 6m x 4m plots were mulched with 100µm thickness PE sheets, from December 12, 1992 to March 7, 1993. Four other plots (same size without the cover were used as control (bare soil. Results indicated that solarization incrased the maximum soil temperature. The average was 11.9, 10.8, 9.8, and 8.6°C over uncovered control soil at 2, 5, 10, and 20cm depth, respectively. The soil temperature reached values of up to 54.4°C at 2cm and 50.2°C at 5cm depth. Temperatures exceeding 45°C and 50°C in solarized soil have also occurred in several days. "Edge effect" in mulched plots was also detected.

  17. Ecological effects of atmospheric nitrogen deposition on soil enzyme activity

    Institute of Scientific and Technical Information of China (English)

    WANG Cong-yan; Lv Yan-na; LIU Xue-yan Liu; WANG Lei

    2013-01-01

    The continuing increase in human activities is causing global changes such as increased deposition of atmospheric nitrogen.There is considerable interest in understanding the effects of increasing atmospheric nitrogen deposition on soil enzyme activities,specifically in terms of global nitrogen cycling and its potential future contribution to global climate change.This paper summarizes the ecological effects of atmospheric nitrogen deposition on soil enzyme activities,including size-effects,stage-effects,site-effects,and the effects of different levels and forms of atmospheric nitrogen deposition.We discuss needs for further research on the relationship between atmospheric nitrogen deposition and soil enzymes.

  18. Spectral effects of light-emitting diodes on photosynthetic characteristics and secondary metabolism in greenhouse plants

    DEFF Research Database (Denmark)

    Ouzounis, Theoharis

    2014-01-01

    , photo-synthetic performance, and secondary metabolism of different plants. As model plants we used rose (Rosa hybrida), chrysanthemum (Chrysanthemum morifolium), campanula (Campanula portenschlagiana), orchid (Phalaenopsis), and lettuce (Lactuca sativa). In our first experiment, by growing roses...... fluorescence measurements. In all three experiments, we also addressed the effects of supplementary blue and red LED lighting on phytochemicals. With increasing amount of blue light, roses, chrysanthemums, and campanulas increased their phenolic amount; Phalaenopsis cultivars increased their pigment content......; lettuce plants increased both their phenolic and pigment content. The effects were not observed in the same way in all plants, highlighting the fact that plant responses to blue and red LED lighting are species and/or cultivar dependent. LED-based systems are a promising alternative choice for greenhouse...

  19. Greenhouse gas emissions from solid waste in Beijing: The rising trend and the mitigation effects by management improvements.

    Science.gov (United States)

    Yu, Yongqiang; Zhang, Wen

    2016-04-01

    Disposal of solid waste poses great challenges to city managements. Changes in solid waste composition and disposal methods, along with urbanisation, can certainly affect greenhouse gas emissions from municipal solid waste. In this study, we analysed the changes in the generation, composition and management of municipal solid waste in Beijing. The changes of greenhouse gas emissions from municipal solid waste management were thereafter calculated. The impacts of municipal solid waste management improvements on greenhouse gas emissions and the mitigation effects of treatment techniques of greenhouse gas were also analysed. Municipal solid waste generation in Beijing has increased, and food waste has constituted the most substantial component of municipal solid waste over the past decade. Since the first half of 1950s, greenhouse gas emission has increased from 6 CO2-eq Gg y(-1)to approximately 200 CO2-eq Gg y(-1)in the early 1990s and 2145 CO2-eq Gg y(-1)in 2013. Landfill gas flaring, landfill gas utilisation and energy recovery in incineration are three techniques of the after-emission treatments in municipal solid waste management. The scenario analysis showed that three techniques might reduce greenhouse gas emissions by 22.7%, 4.5% and 9.8%, respectively. In the future, if waste disposal can achieve a ratio of 4:3:3 by landfill, composting and incineration with the proposed after-emission treatments, as stipulated by the Beijing Municipal Waste Management Act, greenhouse gas emissions from municipal solid waste will decrease by 41%.

  20. The Greenhouse Effect and the Destruction of the Ozone Shield: Implications for Rhetoric and Criticism.

    Science.gov (United States)

    Stoller, Martin Reid

    Rhetoric, in the Aristotelian sense of "the available means of persuasion," is a crucial, often determining component of the process of making public policy generally, and environmental policy specifically. Environmental crises which have been addressed by the governmental, industrial, and social policy -making establishments have tended to be treated in a manner similar to that in which social, political, economic, military, and other problems have been commonly treated, utilizing a traditional rhetoric, including long-proven persuasive language and arguments. Such problems as air pollution and water pollution have been, to some degree, successfully addressed in this manner. A new and fundamentally different cluster of environmental problems has recently been recognized by elements of the policy making establishment as a legitimate candidate for consideration and policy formation. These environmental problems differ from the more familiar type in a variety of ways, each of which, to a greater or lesser degree, make problematic for those activists concerned with these crises the production of an effective crisis-oriented rhetoric. This study addresses two such closely related phenomena, the Greenhouse Effect and ozone depletion, and identifies those characteristics which contribute to their rhetorical complexity. Using traditional techniques of rhetorical examination, primarily neo-Aristotelian analysis, this study demonstrates the inadequacy of current crisis-oriented rhetoric, and identifies the causes of this rhetorical ineffectiveness. The study concludes that the mediation of such crises as the Greenhouse Effect and ozone depletion cannot be significantly facilitated by traditional environmental-oriented rhetoric, and may in fact be hindered by the use of rhetoric associated with fundamentally different (i.e., easier to solve) environmental problems.

  1. High-precision quasi-continuous atmospheric greenhouse gas measurements at Trainou tower (Orléans forest, France)

    Science.gov (United States)

    Schmidt, M.; Lopez, M.; Yver Kwok, C.; Messager, C.; Ramonet, M.; Wastine, B.; Vuillemin, C.; Truong, F.; Gal, B.; Parmentier, E.; Cloué, O.; Ciais, P.

    2014-07-01

    Results from the Trainou tall tower measurement station installed in 2006 are presented for atmospheric measurements of CO2, CH4, N2O, SF6, CO, H2 mole fractions and radon-222 activity. Air is sampled from four sampling heights (180, 100, 50 and 5 m) of the Trainou 200 m television tower in the Orléans forest in France (47°57'53" N, 2°06'45" E, 131 m a.s.l.). The station is equipped with a custom-built CO2 analyser (CARIBOU), which is based on a commercial non-dispersive, infrared (NDIR) analyser (Licor 6252), and a coupled gas chromatography (GC) system equipped with an electron capture detector (ECD) and a flame ionization detector (FID) (HP6890N, Agilent) and a reduction gas detector (PP1, Peak Performer). Air intakes, pumping and air drying system are shared between the CARIBOU and the GC systems. The ultimately achieved short-term repeatability (1 sigma, over several days) for the GC system is 0.05 ppm for CO2, 1.4 ppb for CH4, 0.25 ppb for N2O, 0.08 ppb for SF6, 0.88 ppb for CO and 3.8 for H2. The repeatability of the CARIBOU CO2 analyser is 0.06 ppm. In addition to the in situ measurements, weekly flask sampling is performed, and flask air samples are analysed at the Laboratoire des Sciences du Climat et de l'Environnement (LSCE) central laboratory for the same species as well for stable isotopes of CO2. The comparison between in situ measurements and the flask sampling showed averaged differences of 0.08 ± 1.40 ppm for CO2, 0.7 ± 7.3 ppb for CH4, 0.6 ± 0.6 ppb for N2O, 0.01 ± 0.10 ppt for SF6, 1.5± 5.3 ppb for CO and 4.8± 6.9 ppb for H2 for the years 2008-2012. At Trainou station, the mean annual increase rates from 2007 to 2011 at the 180 m sampling height were 2.2 ppm yr-1 for CO2, 4 ppb yr-1 for CH4, 0.78 ppb yr-1 for N2O and 0.29 ppt yr-1 for SF6. For all species, the 180 m sampling level showed the smallest diurnal variation. Mean diurnal gradients between the 50 m and the 180 m sampling level reached up to 30 ppm CO2, 15 ppm CH4 or 0.5 ppb N2

  2. Biogas in organic agriculture-effects on productivity, energy self-sufficiency and greenhouse gas emissions

    DEFF Research Database (Denmark)

    Pugesgaard, Siri; Olesen, Jørgen E; Jørgensen, Uffe

    2014-01-01

    Anaerobic digestion of manure and crops provides the possibility of a combined production of renewable energy and organic fertilizer on organic farms and has been suggested as an option to improve sustainability of organic agriculture. In the present study, the consequences of implementation...... of anaerobic digestion and biogas production were analyzed on a 1000 ha model farm with combined dairy and cash crop production, representing organic agriculture in Denmark. The effects on crop rotation, nitrogen flows and losses, yield, energy balance and greenhouse gas (GHG) emissions were evaluated for four......, reduced number of livestock and import of biomass from cuttings made in ungrazed meadows. These four scenarios were compared with the current situation in organic agriculture in Denmark and to a situation where slurry from conventional agriculture is no longer imported. Implementation of anaerobic...

  3. Greenhouse effect and ice ages: historical perspective; Effet de serre et glaciations, une perspective historique

    Energy Technology Data Exchange (ETDEWEB)

    Bard, E. [College de France, Chaire d' Evolution du Climat et de l' Ocean, 75 - Paris (France); CEREGE (UMR 6635), 13 - Aix en Provence (France)

    2004-06-01

    This article provides a brief historical perspective on the first scientific research on the greenhouse effect and glaciations. While these two aspects of our climate can be investigated separately, naturalists, physicists and chemists during the 19. century were interested jointly in both issues, as well as the possible relationship between them. The contributions of famous pioneers are mentioned, ranging from scholars with encyclopedic knowledge such as Horace-Benedict de Saussure, to modern scientists like Svante Arrhenius, who was first to predict global warming as a consequence of using fossil fuels. Despite fragmentary observations, these pioneers had prophetic insights. Indeed, the main fundamental concepts used nowadays have been developed during the 19. century. However, we must wait until the second half of the 20. century to see a true revolution of investigative techniques in the Earth Sciences, enabling full access to previously unknown components of the climate system, such as deep oceans and the interior of the polar ice caps. (author)

  4. Nitrogen supply modulates the effect of changes in drying-rewetting frequency on soil C and N cycling and greenhouse gas exchange.

    Science.gov (United States)

    Morillas, Lourdes; Durán, Jorge; Rodríguez, Alexandra; Roales, Javier; Gallardo, Antonio; Lovett, Gary M; Groffman, Peter M

    2015-10-01

    Climate change and atmospheric nitrogen (N) deposition are two of the most important global change drivers. However, the interactions of these drivers have not been well studied. We aimed to assess how the combined effect of soil N additions and more frequent soil drying-rewetting events affects carbon (C) and N cycling, soil:atmosphere greenhouse gas (GHG) exchange, and functional microbial diversity. We manipulated the frequency of soil drying-rewetting events in soils from ambient and N-treated plots in a temperate forest and calculated the Orwin & Wardle Resistance index to compare the response of the different treatments. Increases in drying-rewetting cycles led to reductions in soil NO3- levels, potential net nitrification rate, and soil : atmosphere GHG exchange, and increases in NH4+ and total soil inorganic N levels. N-treated soils were more resistant to changes in the frequency of drying-rewetting cycles, and this resistance was stronger for C- than for N-related variables. Both the long-term N addition and the drying-rewetting treatment altered the functionality of the soil microbial population and its functional diversity. Our results suggest that increasing the frequency of drying-rewetting cycles can affect the ability of soil to cycle C and N and soil : atmosphere GHG exchange and that the response to this increase is modulated by soil N enrichment.

  5. The effects of carbon tax on the Oregon economy and state greenhouse gas emissions

    Science.gov (United States)

    Rice, A. L.; Butenhoff, C. L.; Renfro, J.; Liu, J.

    2014-12-01

    Of the numerous mechanisms to mitigate greenhouse gas emissions on statewide, regional or national scales in the United States, a tax on carbon is perhaps one of the simplest. By taxing emissions directly, the costs of carbon emissions are incorporated into decision-making processes of market actors including consumers, energy suppliers and policy makers. A carbon tax also internalizes the social costs of climate impacts. In structuring carbon tax revenues to reduce corporate and personal income taxes, the negative incentives created by distortionary income taxes can be reduced or offset entirely. In 2008, the first carbon tax in North America across economic sectors was implemented in British Columbia through such a revenue-neutral program. In this work, we investigate the economic and environmental effects of a carbon tax in the state of Oregon with the goal of informing the state legislature, stakeholders and the public. The study investigates 70 different economic sectors in the Oregon economy and six geographical regions of the state. The economic model is built upon the Carbon Tax Analysis Model (C-TAM) to provide price changes in fuel with data from: the Energy Information Agency National Energy Modeling System (EIA-NEMS) Pacific Region Module which provides Oregon-specific energy forecasts; and fuel price increases imposed at different carbon fees based on fuel-specific carbon content and current and projected regional-specific electricity fuel mixes. CTAM output is incorporated into the Regional Economic Model (REMI) which is used to dynamically forecast economic impacts by region and industry sector including: economic output, employment, wages, fiscal effects and equity. Based on changes in economic output and fuel demand, we further project changes in greenhouse gas emissions resulting from economic activity and calculate revenue generated through a carbon fee. Here, we present results of this modeling effort under different scenarios of carbon fee and

  6. Large-eddy simulation, atmospheric measurement and inverse modeling of greenhouse gas emissions at local spatial scales

    Science.gov (United States)

    Nottrott, Anders Andelman

    non-volatile switching of magnetization would be more promising for information storage or MERAM devices with lower energy consumption and the magnetic state can be further controlled by voltage impulse. In this work, we first study the equivalent of direct and converse magnetoelectric effects. The resonant direct and converse magnetoelectric (ME) effects have been investigated experimentally and theoretically in FeGa/PZT/FeGa sandwich laminate composites. The frequency responses of direct and converse magnetoelectric effects were measured under the same electric and magnetic bias conditions. The resonant direct ME effect (DME) occurs at an antiresonance frequency, while resonant converse ME effect (CME) occurs at a resonance frequency. The antiresonance and resonance frequencies have close but different values under identical bias conditions. The magnitudes of resonant effective ME coefficients for direct and converse ME effects are also not equal. Based on different sets of constitutive equations of the materials for DME and CME, a new model was developed to describe the frequency response of DME and CME in laminate composite, which was in good agreement with the experimental results. Inequivalence of resonant ME effects is ascribed to the different mechanical and electrical boundary conditions for DME and CME. On the other hand, similar bias E and H field dependence was observed for both DME and CME resonance frequencies and resonant coefficients, indicating consistency between DME and CME effects. In the study of the frequency response of DME and CME, the linear piezoelectric effect is used. However, this linear piezoelectric effect in converse magnetoelectric coupling would lead to "butter-fly" like magnetization vs. electric field curve which leads to a "volatile" behavior in magnetic memory system. In the presented study, a unique ferroelastic switching pathway in ferroelectric substrates is utilized to produce two distinct, reversible and stable lattice strain

  7. The greenhouse gases

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, R.

    1987-01-01

    The main greenhouse gases are carbon dioxide, methane, nitrous oxide, CFCs and ozone. They are greenhouse gases as they absorb radiation from the Earth and thus impede its emission back to space. CO{sub 2} is responsible for about half the enhanced greenhouse effect. A global warming of only a few degrees would have a profound effect on climate. Increased levels of CO{sub 2} promote plant growth, but may not benefit agriculture overall. Sea levels may rise. It is difficult to predict the effects of global warming in society. It would be possible to reduce the scale of the greenhouse effect by energy conservation, using alternative energy sources, and possibly by capturing CO{sub 2} from fossil fuel power stations and disposing of it on the ocean floor. 13 refs., 19 figs., 1 tab.

  8. Moisture effects on greenhouse gases generation in nitrifying gas-phase compost biofilters.

    Science.gov (United States)

    Maia, Guilherme D N; Day, George B; Gates, Richard S; Taraba, Joseph L; Coyne, Mark S

    2012-06-01

    Gas-phase compost biofilters are extensively used in concentrated animal feeding operations to remove odors and, in some cases, ammonia from air sources. The expected biochemical pathway for these predominantly aerobic systems is nitrification. However, non-uniform media with low oxygen levels can shift biofilter microbial pathways to denitrification, a source of greenhouse gases. Several factors contribute to the formation of anoxic/anaerobic zones: media aging, media and particle structure, air velocity distribution, compaction, biofilm thickness, and moisture content (MC) distribution. The present work studies the effects of media moisture conditions on ammonia (NH(3)) removal and greenhouse gas generation (nitrous oxide, N(2)O and methane, CH(4)) for gas-phase compost biofilters subject to a 100-day controlled drying process. Continuous recordings were made for the three gases and water vapor (2.21-h sampling cycle, each cycle consisted of three gas species, and water vapor, for a total of 10,050 data points). Media moisture conditions were classified into three corresponding media drying rate (DR) stages: Constant DR (wetter media), falling DR, and stable-dry system. The first-half of the constant DR period (0-750 h; MC=65-52%, w.b.) facilitated high NH(3) removal rates, but higher N(2)O generation and no CH(4) generation. At the drier stages of the constant DR (750-950 h; MC=52-48%, w.b.) NH(3) removal remained high but N(2)O net generation decreased to near zero. In the falling DR stage (1200-1480 h; MC=44-13%) N(2)O generation decreased, CH(4) increased, and NH(3) was no longer removed. No ammonia removal or greenhouse gas generation was observed in the stable-dry system (1500-2500 h; MC=13%). These results indicate that media should remain toward the drier region of the constant DR (in close proximity to the falling DR stage; MC=50%, approx.), to maintain high levels of NH(3) removal, reduced levels of N(2)O generation, and nullify levels of CH(4

  9. Cover materials excluding near infrared radiation: effect on greenhouse climate and plant processes

    NARCIS (Netherlands)

    Kempkes, F.L.K.; Stanghellini, C.; Hemming, S.; Dai, J.

    2008-01-01

    Only about half of the energy that enters a greenhouse as sun radiation is in the wavelength range that is useful for photosynthesis (PAR, Photosynthetically Active Radiation). Nearly all the remaining energy fraction is in the Near InfraRed range (NIR) and warms the greenhouse and crop and does con

  10. Effects of Nitrogen Deposition on Greenhouse-Gas Fluxes for Forests and Grasslands of North America

    Science.gov (United States)

    Human activities have substantially elevated the atmospheric deposition of reactive nitrogen (N) onto terrestrial ecosystems of North America. Some of this N can stimulate carbon (C) storage in terrestrial ecosystems, but the fertilization effect of added N can be diminished by e...

  11. Research Advances of Effects of Land Use Pattern on Greenhouse Gas Fluxes in Grassland Ecosystem

    Institute of Scientific and Technical Information of China (English)

    Cheng; Leixing; Chen; Kelong; Wang; Shiping

    2014-01-01

    The grassland is the largest terrestrial ecosystem in China,and greenhouse gas fluxes such as CO2,CH4 and N2O play an important role in the global climate change. The differences in grazing,cultivation and management measures will affect greenhouse gas emissions in grassland ecosystem. Studies suggest that reclamation will lead to increased CO2 fluxes,and fertilization will lead to increased N2 O fluxes; no grazing in summer can reduce greenhouse gas emissions,but impacts of grazing and management measures on greenhouse gas fluxes have not yet reached the same conclusion. The different results may be related to local natural conditions,management measures and research methods. Future research should be focused on unity and standardization in these areas,making the results scientific and comparable,and finally providing the basis for emission reduction of greenhouse gases in grassland ecosystem.

  12. Greenhouse effect: an issue for the refrigeration and air conditioning sector; Effet de serre: quelle problematique pour le froid et le conditionnement de l`air?

    Energy Technology Data Exchange (ETDEWEB)

    Billiard, F. [Institut International du Froid, 75 - Paris (France)

    1997-12-31

    The principles of greenhouse effect and the greenhouse gas main direct and indirect emission sources due to refrigeration and air conditioning systems are first reviewed. Evolution scenarios from 1992 to 2020 and 2100 for the emissions of CFC, HCFC and HFC are presented and related to the Kyoto protocol project limitations; technical improvements in refrigerating and air conditioning systems (lower refrigerant utilization, fluid confinement, alternative technologies, natural refrigerant utilization, etc.) could lead to substantial diminutions of these greenhouse gases

  13. High-sensitivity remote detection of atmospheric pollutants and greenhouse gases at low ppm levels using near-infrared tunable diode lasers

    Science.gov (United States)

    Roy, Anirban; Upadhyay, Abhishek; Chakraborty, Arup Lal

    2016-05-01

    The concentration of atmospheric pollutants and greenhouse gases needs to be precisely monitored for sustainable industrial development and to predict the climate shifts caused by global warming. Such measurements are made on a continuous basis in ecologically sensitive and urban areas in the advanced countries. Tunable diode laser spectroscopy (TDLS) is the most versatile non-destructive technology currently available for remote measurements of multiple gases with very high selectivity (low cross-sensitivity), very high sensitivity (on the order of ppm and ppb) and under hazardous conditions. We demonstrate absolute measurements of acetylene, methane and carbon dioxide using a fielddeployable fully automated TDLS system that uses calibration-free 2f wavelength modulation spectroscopy (2f WMS) techniques with sensitivities of low ppm levels. A 40 mW, 1531.52 nm distributed feedback (DFB) diode laser, a 10 mW, 1650 nm DFB laser and a 1 mW, 2004 nm vertical cavity surface emitting laser (VCSEL) are used in the experiments to probe the P9 transition of acetylene, R4 transition of methane and R16 transition of carbon dioxide respectively. Data acquisition and on-board analysis comprises a Raspberry Pi-based embedded system that is controllable over a wireless connection. Gas concentration and pressure are simultaneously extracted by fitting the experimental signals to 2f WMS signals simulated using spectroscopic parameters obtained from the HITRAN database. The lowest detected concentration is 11 ppm for acetylene, 275 ppm for methane and 285 ppm for carbon dioxide using a 28 cm long single-pass gas cell.

  14. Global Warming and the Greenhouse Effect: January 1986-January 1992. Quick Bibliography Series: QB 92-36.

    Science.gov (United States)

    MacLean, Jayne T.

    This bibliography contains 442 journal article, book, and audiovisual citations on global warming and the greenhouse effect entered into the National Agricultural Library's AGRICOLA database between January 1979 and March 1992. The bibliography contains an author and subject index as well as information on obtaining documents. (LZ)

  15. Students' Understanding of the Greenhouse Effect, the Societal Consequences of Reducing CO2 Emissions and the Problem of Ozone Layer Depletion.

    Science.gov (United States)

    Andersson, Bjorn; Wallin, Anita

    2000-01-01

    Contributes to the growing body of knowledge about students' conceptions and views of environmental and natural resource issues. Questions 9th and 12th grade Swedish students' understandings of the greenhouse effect, reduction of CO2 emissions, and the depletion of the ozone layer. Observes five models of the greenhouse effect that appear among…

  16. The Impact of Secondary School Students' Preconceptions on the Evolution of their Mental Models of the Greenhouse effect and Global Warming

    Science.gov (United States)

    Reinfried, Sibylle; Tempelmann, Sebastian

    2014-01-01

    This paper provides a video-based learning process study that investigates the kinds of mental models of the atmospheric greenhouse effect 13-year-old learners have and how these mental models change with a learning environment, which is optimised in regard to instructional psychology. The objective of this explorative study was to observe and analyse the learners' learning pathways according to their previous knowledge in detail and to understand the mental model formation processes associated with them more precisely. For the analysis of the learning pathways, drawings, texts, video and interview transcripts from 12 students were studied using qualitative methods. The learning pathways pursued by the learners significantly depend on their domain-specific previous knowledge. The learners' preconceptions could be typified based on specific characteristics, whereby three preconception types could be formed. The 'isolated pieces of knowledge' type of learners, who have very little or no previous knowledge about the greenhouse effect, build new mental models that are close to the target model. 'Reduced heat output' type of learners, who have previous knowledge that indicates compliances with central ideas of the normative model, reconstruct their knowledge by reorganising and interpreting their existing knowledge structures. 'Increasing heat input' type of learners, whose previous knowledge consists of subjective worldly knowledge, which has a greater personal explanatory value than the information from the learning environment, have more difficulties changing their mental models. They have to fundamentally reconstruct their mental models.

  17. Anthropogenic effects on greenhouse gas (CH4 and N2O) emissions in the Guadalete River Estuary (SW Spain).

    Science.gov (United States)

    Burgos, M; Sierra, A; Ortega, T; Forja, J M

    2015-01-15

    Coastal areas are subject to a great anthropogenic pressure because more than half of the world's population lives in its vicinity causing organic matter inputs, which intensifies greenhouse gas emissions into the atmosphere. Dissolved concentrations of CH4 and N2O have been measured seasonally during 2013 in the Guadalete River Estuary, which flows into the Cadiz Bay (southwestern Spanish coast). It has been intensely contaminated since 1970. Currently it receives wastewater effluents from cities and direct discharges from nearby agriculture crop. Eight sampling stations have been established along 18 km of the estuary. CH4 and N2O were measured using a gas chromatograph connected to an equilibration system. Additional parameters such as organic matter, dissolved oxygen, nutrients and chlorophyll were determinate as well, in order to understand the relationship between physicochemical and biological processes. Gas concentrations increased from the River mouth toward the inner part, closer to the wastewater treatment plant discharge. Values varied widely within 21.8 and 3483.4 nM for CH4 and between 9.7 and 147.6 nM for N2O. Greenhouse gas seasonal variations were large influenced by the precipitation regime, masking the temperature influence. The Guadatete Estuary acted as a greenhouse gas source along the year, with mean fluxes of 495.7 μmol m(-2)d(-1) and 92.8 μmol m(-2)d(-1) for CH4 and N2O, respectively.

  18. Cost-effectiveness analysis of policy instruments for greenhouse gas emission mitigation in the agricultural sector.

    Science.gov (United States)

    Bakam, Innocent; Balana, Bedru Babulo; Matthews, Robin

    2012-12-15

    Market-based policy instruments to reduce greenhouse gas (GHG) emissions are generally considered more appropriate than command and control tools. However, the omission of transaction costs from policy evaluations and decision-making processes may result in inefficiency in public resource allocation and sub-optimal policy choices and outcomes. This paper aims to assess the relative cost-effectiveness of market-based GHG mitigation policy instruments in the agricultural sector by incorporating transaction costs. Assuming that farmers' responses to mitigation policies are economically rationale, an individual-based model is developed to study the relative performances of an emission tax, a nitrogen fertilizer tax, and a carbon trading scheme using farm data from the Scottish farm account survey (FAS) and emissions and transaction cost data from literature metadata survey. Model simulations show that none of the three schemes could be considered the most cost effective in all circumstances. The cost effectiveness depends both on the tax rate and the amount of free permits allocated to farmers. However, the emissions trading scheme appears to outperform both other policies in realistic scenarios.

  19. The size and range effect: lifecycle greenhouse gas emissions of electric vehicles

    Science.gov (United States)

    Ager-Wick Ellingsen, Linda; Singh, Bhawna; Hammer Strømman, Anders

    2016-05-01

    The primary goal of this study is to investigate the effect of increasing battery size and driving range to the environmental impact of electric vehicles (EVs). To this end, we compile cradle-to-grave inventories for EVs in four size segments to determine their climate change potential. A second objective is to compare the lifecycle emissions of EVs to those of conventional vehicles. For this purpose, we collect lifecycle emissions for conventional vehicles reported by automobile manufacturers. The lifecycle greenhouse gas emissions are calculated per vehicle and over a total driving range of 180 000 km using the average European electricity mix. Process-based attributional LCA and the ReCiPe characterisation method are used to estimate the climate change potential from the hierarchical perspective. The differently sized EVs are compared to one another to find the effect of increasing the size and range of EVs. We also point out the sources of differences in lifecycle emissions between conventional- and electric vehicles. Furthermore, a sensitivity analysis assesses the change in lifecycle emissions when electricity with various energy sources power the EVs. The sensitivity analysis also examines how the use phase electricity sources influences the size and range effect.

  20. Effect of Biochar on Greenhouse Gas Emissions and Nitrogen Cycling in Laboratory and Field Experiments

    Science.gov (United States)

    Hagemann, Nikolas; Harter, Johannes; Kaldamukova, Radina; Ruser, Reiner; Graeff-Hönninger, Simone; Kappler, Andreas; Behrens, Sebastian

    2014-05-01

    The extensive use of nitrogen (N) fertilizers in agriculture is a major source of anthropogenic N2O emissions contributing 8% to global greenhouse gas emissions. Soil biochar amendment has been suggested as a means to reduce both CO2 and non-CO2 greenhouse gas emissions. The reduction of N2O emissions by biochar has been demonstrated repeatedly in field and laboratory experiments. However, the mechanisms of the reduction remain unclear. Further it is not known how biochar field-weathering affects GHG emissions and how agro-chemicals, such as the nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP), that is often simultaneously applied together with commercial N-fertilizers, impact nitrogen transformation and N2O emissions from biochar amended soils. In order investigate the duration of the biochar effect on soil N2O emissions and its susceptibility to DMPP application we performed a microcosm and field study with a high-temperature (400 ° C) beech wood derived biochar (60 t ha-1 and 5 % (w/w) biochar in the field and microcosms, respectively). While the field site contained the biochar already for three years, soil and biochar were freshly mixed for the laboratory microcosm experiments. In both studies we quantified GHG emissions and soil nitrogen speciation (nitrate, nitrite, ammonium). While the field study was carried out over the whole vegetation period of the sunflower Helianthus annuus L., soil microcosm experiments were performed for up to 9 days at 28° C. In both experiments a N-fertilizer containing DMPP was applied either before planting of the sunflowers or at the beginning of soil microcosms incubation. Laboratory microcosm experiments were performed at 60% water filled pore space reflecting average field conditions. Our results show that biochar effectively reduced soil N2O emissions by up to 60 % in the field and in the soil microcosm experiments. No significant differences in N2O emission mitigation potential between field-aged and fresh

  1. The carbon balance and greenhouse effects of the Finnish forest sector at present, in the past and future

    Energy Technology Data Exchange (ETDEWEB)

    Pingoud, K. [Technical Research Centre of Finland, Espoo (Finland)

    1996-12-31

    In this study the greenhouse impact of the total Finnish forest sector was considered, which means that the estimated emissions and sink effects from exported forest products were also included. The forest biomass is and seems to be in the next decades the most important factor in the carbon balance of the total forest sector. The development alternatives of forest industries and waste management practices has still a remarkable influence on the greenhouse impact of the Finnish forest sector. The waste management practices in the future has an important influence on the emissions but the exact net greenhouse impact of the landfills is still uncertain. However, the methane emissions from existing landfills can be reduced essentially by gas recovery. Increased incineration and energy recovery of wood waste (and replacing fossil fuel use by it) is also a future alternative for reducing the greenhouse effects in the forest sector. The sequestration of carbon by increasing the storages of long-lived wood products in use meets difficulties in practice because of all the material losses in wood using chain and the natural removal of old wood products. An important advantage of mechanical wood processing and the succeeding refinement chain is still their relative low use of energy

  2. Effect of solid and aqueous extract of vermicompost on growth characteristics of tomato and greenhouse whitefly (Trialeurodes vaporariorum

    Directory of Open Access Journals (Sweden)

    A. Peimani Foroushani

    2016-09-01

    Full Text Available Considering the increase of using vermicompost fertilizers in greenhouse cultivation, effect of vermicompost application on growth characteristics of tomato and one of its major pests [greenhouse whitefly, Trialeurodes vaporariorum (Hem:Aleyrodidae] was investigated. The experiment consisted of five treatments: control (without vermicompost, 30% and 60% solid vermicompost fertilizer, and 40% and 20% aqueous extracts of vermicompost. Effect of vermicompost on greenhouse whitefly was tested for two different cases of with-choice and no-choice. Results showed that significant increase in shoot dry weight and root dry weight of tomato in vermicompost treatments. The highest increase (18 and 12 fold, respectively was observed in plants treated with 60% solid vermicompost. The highest amount of nitrogen (0.43 mg/kg, potassium (14.56 mg/kg and phenol (1130.46 ppm was recorded in60% solid vermicompost treatment. Also, application of vermicompost reduced the percentage of infested leaves to whitefly, such that the lowest amounts were 6.67% and 8.97% in 60% and 30% solid vermicompost treatments, respectively, and 10.53% in 40% aqueous extract of vermicompost. The mortality of the second instar nymph of greenhouse whitefly-the stage that insects become fixed to the leaves by their sucking mouthparts- was increased (about 10% by application of  vermicompost.

  3. Operation GREENHOUSE-1951

    Science.gov (United States)

    1983-06-15

    Identify by block number) GREENHOUSE was a four-detonation atmospheric nuclear weapon’s test series conducted in the Marshall Islands at Enewetak Atoll in...on the islands of Enjebi, Eleleron. and Runit on Enewetak Atoll . All four were detonated on towers. These detonations resulted In slg- nificant...daily missions. Fallout exposure can be calcu- lated for all Individuals based upon their location and length of stay at Enewetak Atoll . By - - :i

  4. Greenhouse effect gases (GEI) by energy consumption; Gases efecto invernadero (GEI) por consumo de energia

    Energy Technology Data Exchange (ETDEWEB)

    Munoz Ledo C, Ramon; Bazan N, Gerardo [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2003-07-01

    The purpose of this article is to present the calculation methodology of greenhouse effect gases (GEI) emissions that are produced by the power sector in Mexico, as well as to discuss its possible impact in the subject of climatic change and the possible mitigating actions to lower the amount of emissions that can be taken and, therefore, the possible climate changes. In Mexico GEI inventories have been made since 1991, year in which the National Inventory of Gases with Greenhouse Effect was obtained for year 1988. The GEI include carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NOx), methane (CH4), nitrous oxide (NO) and volatile organic carbides that are not methane (NMVOC) and are secondary products and harmful that are obtained from the processes that turn fuels into energy (combustion). The main sources of GEI are: fixed sources (industries, residences, commerce, public services and energy transformation, such as power generation); movable sources (that include all type of transport that uses fuel). The fuels that, by their volume and efficiency, generate more emissions of GEI are crude oil, natural gas and solid biomass (firewood-cane bagasse). Any effort to reduce these emissions is very important and remarkable if it affects the consumption of these fuels. [Spanish] El proposito de este articulo es presentar la metodologia de calculo de las emisiones de los gases con efecto invernadero (GEI) que son producidos por el sector energetico en Mexico, asi como discutir su posible impacto en las cuestiones de cambio climatico y las posibles acciones de mitigacion que se pueden realizar para abatir la cantidad de emisiones y, por ende, los posibles cambios de clima. En Mexico se han realizado inventarios de GEI desde 1991, ano en que se obtuvo el Inventario Nacional de Gases con Efecto Invernadero para el ano de 1988. Los GEI comprenden al dioxido de carbono (CO2), monoxido de carbono (CO), oxidos de nitrogeno (NOx), metano (CH4), oxido nitroso (N2O) y

  5. Evaluation of effective factors on optimal management greenhouses summery in Khuzestan province

    Directory of Open Access Journals (Sweden)

    H. Rahmany

    2012-09-01

    Full Text Available It pays attention to cultivation greenhouse, and provides produce artificial condition and the variants environment have especially important for neutralizing in progressing extent agriculture processes. It is necessary for progressing we need suitable planning until we can move forward to producing program and we are needed to know about variants and limitation which obstacle the develop of this plantation . It is based on this research, general object for recognizing important variants than the useful management of the summer greenhouses in Khuzestan province do it. This research is a kind of usage and it conducted by measurement method in Khuzestan province. We use for gathering information from questionnaire achieve and interview method. In the research of the statistical social. There are 95 unite of the summery greenhouse of province. In order to, experts use of panel method for determining validity. They divided 30 the kind of the questionnaire and then gathering them, they calculate score 11.5 of kourenbakh (α coefficient by SPSS software. This coefficient calculates for 2 parts, sustainable agriculture and skillful knowledge are %71 and %82 respectively. The results of research showed that age, courses studies and experience of owner`s greenhouse can make important differences in optimum management level. And also There are statistical significant relationship between the skillful knowledge of the owner`s greenhouse and their perception to sustainable agriculture with useful management. Additionally, education level couldn't affect on optimum management in summery greenhouses.

  6. Effect of irrigation with treated municipal wastewater on yield of Nitraria schoberi under greenhouse conditions

    Directory of Open Access Journals (Sweden)

    A. R. Shahriari

    2011-03-01

    Full Text Available Water crisis is an important issue in arid and semi-arid regions like Iran. Due to drought events, the situation has become more acute in recent years. Therefore, where good quality water is not available, the use of unconventional water has increased considerably. One of these resources is municipal wastewater that can also provide some of the nutrients needed for plant nutrition. Therefore, in this research, the combined effects of treated municipal wastewater and soil texture on growth and yield of Nitraria schoberi under greenhouse conditions, was investigated. The experiment was a factorial completely randomized design with four replications. The treatments included: two types of irrigation water (wastewater and water, two soil textures (clay and sandy and two irrigation frequencies (5 and 15 days. Analysis of the wastewater showed that concentrations of the elements were in the standard limits. The results also showed that the use of wastewater has positive effect on stem length and dry and fresh weight of the plants. Therefore, due to the problem of water supply to plant species in the arid regions, this method can have a significant role in the stability of plants, reducing costs of irrigation and fertilizers, and biological restoration.

  7. Effect of some Trichoderma spp. isolates on promoting growth of cucumber seedlings under greenhouse conditions

    Directory of Open Access Journals (Sweden)

    M. Taghinasab Darzi

    2012-12-01

    Full Text Available This experiment was performed to investigate the effect of some Trichoderma spp. isolates as growth promoters of cucumber (Cucumis sativus L. seedlings under greenhouse conditions. Inoculai of 19 Thrichoderma spp. isolates were prepared from disinfected wheat grain. The upper half of the soil in pots (containing field soil and sand was mixed with these inoculai at 3% ratio and the pots were irrigated with tap water for 28 days. After four weeks, the seedlings were sampled for growth comparison on stem length, root length and total fresh weight. The results showed that some isolates improved significantly the cucumber seedlings’ growth and others had inhibitory effect. Application of Trichoderma spp. 17 and T. longibraciatum increased stem length more than 74% as compared to control. Also, these isolates increased significantly P<0.05 the total fresh weight about 40% and 25%, respectively, as compared to control. Furthermore, Trichoderma sp. 19 decreased significantly the stem length, root length and total fresh weight as compared to control. These results show the ability of Persian Trichoderma spp. isolates in promoting cucumber growth and its potential for other plants.

  8. Effect of Atmospheric Conditions on LIBS Spectra

    Directory of Open Access Journals (Sweden)

    Andrew J. Effenberger

    2010-05-01

    Full Text Available Laser-induced breakdown spectroscopy (LIBS is typically performed at ambient Earth atmospheric conditions. However, interest in LIBS in other atmospheric conditions has increased in recent years, especially for use in space exploration (e.g., Mars and Lunar or to improve resolution for isotopic signatures. This review focuses on what has been reported about the performance of LIBS in reduced pressure environments as well as in various gases other than air.

  9. ADVANCES IN RESERVOIR GREENHOUSE EFFECTS AND PRINCIPAL INFLUENCE FACTORS ANALYSIS%水库温室效应研究进展与主要影响因素分析

    Institute of Scientific and Technical Information of China (English)

    冉景江; 林初学; 郭劲松; 陈永柏; 蒋滔

    2011-01-01

    温室气体排放导致的全球变暖成为世界各国关注的焦点.目前,关于淡水水库的温室效应在全球气候变化中的作用也成为了科学家争论的问题.已有的研究表明,世界上很多为水力发电或其他目的建造的水库,因水库蓄水所导致土壤和植被的淹没而额外增加碳基温室气体二氧化碳(C02)和甲烷(CH4)的释放.通过对国内外关于淡水水库温室气体研究方面文献的归纳,综述分析了水库温室效应观测研究案例、水库温室气体的产生机制、排放过程及其主要影响因素等方面的研究进展.为进一步从事水库温室气体研究、把握水库温室气体排放提供参考.%Global climate warming resulted from greenhouse gas emission already has attracted more and more attentions from governments and the public all over the world. At present, the status of greenhouse effect from large freshwater reservoirs in global climate warming became a debated issue in the academic community around the world gradually. The previous studies showed that some reservoirs for hydro-electronic generation or other purposes in Canada, U. S. A, Brazil and other counties would release additional greenhouse gas(CO2 and CH4)into atmosphere due to the inundation of soil and vegetation in reservoir area as a result of the construction and impoundment of reservoir. In this paper, an overview of greenhouse effect of reservoir on the global warming was addressed in order to understand the advances in greenhouse gas researches at home and abroad. It should be illustrated that some key issues,including observation of reservoirs greenhouse effect, case studies, the inner mechanism, emission processes and main influence factor of greenhouse gas from reservoirs, wese discussed and summarized for the sake of obtaining more information about the emission of greenhouse gas from freshwater reservoirs and providing constructive guide for hydro-electronic development in China.

  10. Eutrophication effects on greenhouse gas fluxes from shallow-lake mesocosms override those of climate warming.

    Science.gov (United States)

    Davidson, Thomas A; Audet, Joachim; Svenning, Jens-Christian; Lauridsen, Torben L; Søndergaard, Martin; Landkildehus, Frank; Larsen, Søren E; Jeppesen, Erik

    2015-12-01

    Fresh waters make a disproportionately large contribution to greenhouse gas (GHG) emissions, with shallow lakes being particular hot spots. Given their global prevalence, how GHG fluxes from shallow lakes are altered by climate change may have profound implications for the global carbon cycle. Empirical evidence for the temperature dependence of the processes controlling GHG production in natural systems is largely based on the correlation between seasonal temperature variation and seasonal change in GHG fluxes. However, ecosystem-level GHG fluxes could be influenced by factors, which while varying seasonally with temperature are actually either indirectly related (e.g. primary producer biomass) or largely unrelated to temperature, for instance nutrient loading. Here, we present results from the longest running shallow-lake mesocosm experiment which demonstrate that nutrient concentrations override temperature as a control of both the total and individual GHG flux. Furthermore, testing for temperature treatment effects at low and high nutrient levels separately showed only one, rather weak, positive effect of temperature (CH4 flux at high nutrients). In contrast, at low nutrients, the CO2 efflux was lower in the elevated temperature treatments, with no significant effect on CH4 or N2 O fluxes. Further analysis identified possible indirect effects of temperature treatment. For example, at low nutrient levels, increased macrophyte abundance was associated with significantly reduced fluxes of both CH4 and CO2 for both total annual flux and monthly observation data. As macrophyte abundance was positively related to temperature treatment, this suggests the possibility of indirect temperature effects, via macrophyte abundance, on CH4 and CO2 flux. These findings indicate that fluxes of GHGs from shallow lakes may be controlled more by factors indirectly related to temperature, in this case nutrient concentration and the abundance of primary producers. Thus, at ecosystem

  11. On the effect of emissions from aircraft engines on the state of the atmosphere

    Directory of Open Access Journals (Sweden)

    U. Schumann

    Full Text Available Emissions from aircraft engines include carbon dioxide, water vapour, nitrogen oxides, sulphur components and various other gases and particles. Such emissions from high-flying global civil subsonic air traffic may cause anthropogenic climate changes by an increase of ozone and cloudiness in the upper troposphere, and by an enhanced greenhouse effect. The absolute emissions by air traffic are small (a few percent of the total compared to surface emissions. However, the greenhouse effect of emitted water and of nitrogen oxides at cruise altitude is potentially large compared to that of the same emissions near the earth's surface because of relatively large residence times at flight altitudes, low background concentrations, low temperature, and large radiative efficiency. Model computations indicate that emission of nitrogen oxides has doubled the background concentration in the upper troposphere between 40°N and 60°N. Models also indicate that this causes an increase of ozone by about 5-20%. Regionally, the observed annual mean change in cloudiness is 0.4%. It is estimated that the resultant greenhouse effect of changes in ozone and thin cirrus cloud cover causes a climatic surface temperature change of 0.01-0.1 K. These temperature changes are small compared to the natural variability. Recent research indicates that the emissions at cruise altitude may increase the amount of stratospheric aerosols and polar stratospheric clouds and thereby have an impact on the atmospheric environment. Air traffic is increasing about 5-6% per year, fuel consumption by about 3%, hence the effects of the related emissions are expected to grow. This paper surveys the state of knowledge and describes several results from recent and ongoing research.

  12. Prospective Turkish elementary science teachers’ knowledge level about the greenhouse effect and their views on environmental education in university

    OpenAIRE

    KIŞOĞLU, Mustafa; Hasan GÜRBÜZ; Erkol, Mehmet; Muhammed Said AKAR; Mustafa AKILLI

    2010-01-01

    The fundamental factor of environmental education is teachers who are well-informed about environmental issues. This research aimed to determine prospective Turkish elementary science teachers’ knowledge level about causes, consequences and reducing of the greenhouse effect and to investigate the effect of gender, information source and membership in the environmental foundations on their knowledge. We also aimed to learn their views on environmental education given in university. Twenty-six ...

  13. [Effects of nutrition medium on cucumber growth and soil microenvironment in greenhouse under continuous cropping].

    Science.gov (United States)

    Wu, Chun-Cheng; Li, Tian-Lai; Cao, Xia; Meng, Si-Da; Zhang, Yong-Yong; Yang, Li-Juan

    2014-05-01

    An experiment of continuous cropping of cucumber in nutrition medium (composted with straw, rural soil and puffed chicken manure) or soil was conducted in greenhouse in order to study the effects of medium type on the cucumber growth and soil microenvironment, respectively. The results showed that the two treatments both displayed different levels of obstacles resulted from continuous cropping. In the same cropping season, the nutrient content, soil invertase and urease activities and B/F (bacteria/fungi) ratio in the nutrition medium were obviously higher but fungi quantity was lower than in the soil medium, suggesting the use of nutrition medium changed the bacterial population structure as to improve the cucumber growth and yield. Under continuous cropping, correlation analysis showed that the bacterial quantity was significantly positively related with plant height and root dry mass, and markedly significantly positive correlation exited between the aboveground dry mass and yield of cucumber. The urease activity was also significantly positively related with the cucumber yield. Compared with the soil medium, the nutrition medium could greatly improve soil microenvironment and alleviate the continuous cropping obstacle.

  14. [Effects of fertilization on the P accumulation and leaching in vegetable greenhouse soil].

    Science.gov (United States)

    Zhao, Ya-jie; Zhao, Mu-qiu; Lu, Cai-yan; Shi, Yi; Chen, Xin

    2015-02-01

    A packed soil column experiment was conducted to investigate the effect of different fertilization practices on phosphorus (P) accumulation and leaching potential in a vegetable greenhouse soil with different fertility levels. The results showed that the leaching loss of total P in the leachates elevated with the increment of leaching time while the accumulative leaching loss of total P was relatively low, indicating P was mainly accumulated in the soil instead of in the leachate. At the end of the leaching experiment, soil fertility and fertilization treatment affected the content of total phosphorus and Olsen-P significantly. Compared with the low-level-fertility soil, the contents of total P and Olsen-P increased by 14.3% and 12.2% in the medium-level-fertility soil, 33.3% and 37.7% in the high-level-fertility soil. Total P in the combined application of poultry manure and chemical fertilizer (M+NPK) was elevated by 5.7% and 4.3%, compared with the NPK and M treatment. Compared with NPK treatment, Olsen-P in M and M + NPK treatments augmented by 13.0% and 3.1%, respectively. Soil total P and Olsen-P mainly accumulated in the 0-10 cm and 10-20 cm soil layers, and much less in the 20-40 cm soil layer.

  15. Runaway greenhouse effect on exomoons due to irradiation from hot, young giant planets

    CERN Document Server

    Heller, René

    2013-01-01

    The Kepler space telescope has detected transits of objects as small as the Earth's Moon, and moons as small as 0.2 Earth masses can be detected in the Kepler data by transit timing and transit duration variations of their host planets. Such massive moons around giant planets in the stellar habitable zone (HZ) could serve as habitats for extraterrestrial life. We here assess the danger of exomoons to be in a runaway greenhouse (RG) state due to extensive heating from the planet. We apply pre-computed evolution tracks for giant planets to calculate the incident planetary radiation on the moon as a function of time. The total energy budget of stellar flux, illumination from the planet, and tidal heating in the satellite is compared to the critical flux for the moon to experience an RG effect. Irradiation from a 13-Jupiter-mass planet onto an Earth-sized moon at a distance of ten Jupiter radii can drive an RG state on the moon for about 200 Myr. If stellar illumination equivalent to that received by Earth from t...

  16. Quantification of the effects on greenhouse gas emissions of policies and measures. Methodologies report

    Energy Technology Data Exchange (ETDEWEB)

    Forster, D.; Falconer, A. [AEA Technology, Didcot (United Kingdom); Buttazoni, M.; Greenleaf, J. [Ecofys, Utrecht (Netherlands); Eichhammer, W. [Fraunhofer Institut fuer System- und Innovationsforschung ISI, Karlsruhe (DE)] (and others)

    2009-12-15

    The primary aim of the report is to describe the methodologies that have been developed during the project to evaluate, ex-post, the impact of selected EU Climate Change Policies and Measures (PAMS) on greenhouse gas (GHG) emissions. The secondary aim of the document is to provide guidance to Member State (MS) representatives on ex-post evaluation, and to provide references and tools that facilitate the implementation of a consistent approach across the EU27 countries. The focus of the guidance is on approaches to evaluate the effectiveness of the policies and measures. Evaluating the efficiency of policies is another important component of policy evaluation, but is only considered to a limited extent within these guidelines. Section 2 discusses the broad methodological issues associated with expost evaluation, illustrating the main approaches available and their strengths and weaknesses. Section 3 describes the methodological framework proposed for the evaluation of EU Climate Change Policies, providing explanation of key decisions informing the approach and the actual guidelines for the policy evaluation of individual directives. Section 4 includes policy evaluation guidelines for a large number of different EU climate change policies. Section 5 includes concluding remarks on the role the guidelines could play in EU and MS climate change policy and on their possible future evolution. The Appendices comprise (1) a working Paper on methodological issues related to the calculation of emission factors; (2) case study applications of a Tier 3 methodology.

  17. Effect of Rotation Crops on Heterodera glycines Population Density in a Greenhouse Screening Study

    Science.gov (United States)

    Warnke, S.A.; Chen, S.Y.; Wyse, D.L.; Johnson, G.A.; Porter, P.M.

    2006-01-01

    Crop rotation is a common means of reducing pathogen populations in soil. Several rotation crops have been shown to reduce soybean cyst nematode (Heterodera glycines) populations, but a comprehensive study of the optimal crops is needed. A greenhouse study was conducted to determine the effect of growth and decomposition of 46 crops on population density of H. glycines. Crops were sown in soil infested with H. glycines. Plants were maintained until 75 days after planting, when the soil was mixed, a sample of the soil removed to determine egg density, and shoots and roots chopped and mixed into the soil. After 56 days, soil samples were again taken for egg counts, and a susceptible soybean (‘Sturdy’) was planted in the soil as a bioassay to determine egg viability. Sunn hemp (Crotalaria juncea), forage pea (Pisum sativum), lab-lab bean (Lablab purpureus), Illinois bundleflower (Desman-thus illinoensis), and alfalfa (Medicago sativa) generally resulted in smaller egg population density in soil or number of cysts formed on soybean in the bioassay than the fallow control. Sunn hemp most consistently showed the lowest numbers of eggs and cysts. As a group, legumes resulted in lower egg population densities than monocots, Brassica species, and other dicots. PMID:19259545

  18. Potato (Solanum tuberosum) greenhouse tuber production as an assay for asexual reproduction effects from herbicides.

    Science.gov (United States)

    Olszyk, David; Pfleeger, Thomas; Lee, E Henry; Plocher, Milton

    2010-01-01

    The present study determined whether young potato plants can be used as an assay to indicate potential effects of pesticides on asexual reproduction. Solanum tuberosum (Russet Burbank) plants were grown from seed pieces in a mineral soil in pots under greenhouse conditions. Plants were treated with herbicides (cloransulam, dicamba, glyphosate, imazapyr, primsulfuron, sulfometuron, or tribenuron) at simulated drift levels [effective concentrations producing a 25% potato tuber fresh weight (EC25) of 0.00038, 0.0016, and 0.0021 x f.a.r. of 1,124, 52, and 9 g active ingredient hectare(-1) (g a.i. HA(-1)), respectively. Primisulfuron, dicamba, and cloransulam also significantly reduced tuber fresh weight, but with higher EC25 values of 0.011, 0.07, and 0.010 to 0.2 x f.a.r. of 40, 558, and 18 g a.i. HA(-1), respectively. Glyphosate had little effect on tuber fresh weight, with a significant reduction in only one experiment. Sulfometuron reduced tuber fresh weight at an EC25 value lower than the EC25 values for shoot dry weight or plant height. For other herbicides, the reduction in tuber fresh weight occurred within the range of EC25 values for other responses. Although additional experiments are required to develop further a phytotoxicity test, these results indicated that tuber production in young potato plants (harvested approximately 42 DAE) may be an effective assay for below-ground asexual reproductive responses to herbicides, especially acetolactate synthase inhibitors.

  19. TESTING SIDE-EFFECTS OF COMMON PESTICIDES ON A. SWIRSKII UNDER GREENHOUSE CIRCUMSTANCES.

    Science.gov (United States)

    Audenaert, J; Vissers, M; Gobin, B

    2014-01-01

    If a grower uses predatory mites, and should use chemical compounds, he needs to be very careful in his choice of products. The selected products have to be efficient against the target pest and at the same time compatible with the present beneficial's. Useful tools for such product selection under greenhouse circumstances are side effects lists. These lists are freely available on the websites of producing companies of biological control agents. But not all products (e.g. newly developed ones) have been tested for side effects. Moreover the information already available in these tables is not based on field tests. For this reason, we have developed a protocol for quick screening of side effects of chemical plant protection products under field conditions. For these experiments we have chosen the predatory mite Amblyseius swirskii as test organism, because this is an often used phytoseiid mite, which is very sensitive to pesticides. Hibiscus rosa sinensis is the standard reference plant in our side effects trials because the chosen predatory mite has shown very good control of pests on this plant species. The experimental design consists of eight test objects in 4 replications. Test object 1 is a positive reference (water spray) and test object 2 a negative reference (deltamethrin spray, a product with long residual activity against beneficial organisms). The plot size is 0,68 m2 and each plot contains 32 Hibiscus plants. The greenhouse temperature is set at 20±2°C. The test strategy has the following sequence: introduction of an overdose of Amblyseius swirskii mites 14 days before spraying the pesticides > precount of predatory mites 4 days before application (4DBA) > spray application (A) for the 6 test products and for the 2 references > counting's after application (1, 2, 4, 8 en 12 weeks after application = 1 till 12WAA). The counting's of the number of predatory mites are performed on 20 Hibiscus leaves/plot under a binocular. Because of the absence of any

  20. Long-Term Effect of Organic and Mineral Fertilization on Soil Physical Properties Under Greenhouse and Outdoor Management Practices

    Institute of Scientific and Technical Information of China (English)

    J. F. HERENCIA; P. A. GARC(I)A-GALAV(I)S; C. MAQUEDA

    2011-01-01

    To evaluate the use of organic amendments as an alternative to conventional fertilization,a 10-year experiment on a loam soil was conducted under a crop rotation system in both greenhouse and outdoor plots applied with chemical fertilizers (NPK) and vegetal compost (organic fertilizer) in the Guadalquivir River Valley,Spain.The effect of these two different fertilization regimes on the soil physical properties was evaluated.Soil organic carbon (OC),soil bulk density (BD),soil water retention (WR),available water content (AWC),aggregate stability (AS),and soil physical quality (Dexter's index,S) were determined.The use of organic fertilizer increased OC and resulted in a significant increase in AS and a decrease in BD compared to the mineral fertilizer application in both greenhouse and outdoor plots.The outdoor plots showed the lowest BD values whereas the greenhouse plots showed the highest AS values.In the last years of the 10-year experiment the S parameter was significantly higher in organic fertilizer plots,especially for greenhouse plots.At the end of the study period,there were no significant differences in WR at field capacity (FC) between treatments in both systems; the AWC was also similar in the greenhouse plots but higher in the mineral outdoor plots.In mineral fertilizer treatments,a small improvement in the physical properties was also observed due to the utilization of less aggressive tillage compared with the previous intensive cropping system.Physical soil properties were correlated with soil OC.The sustainable management techniques such as the use of organic amendments and low or no tillage improved soil physical properties,despite the differences in management that logically significantly affected the results.

  1. Engineering concepts for inflatable Mars surface greenhouses

    Science.gov (United States)

    Hublitz, I.; Henninger, D. L.; Drake, B. G.; Eckart, P.

    2004-01-01

    A major challenge of designing a bioregenerative life support system for Mars is the reduction of the mass, volume, power, thermal and crew-time requirements. Structural mass of the greenhouse could be saved by operating the greenhouse at low atmospheric pressure. This paper investigates the feasibility of this concept. The method of equivalent system mass is used to compare greenhouses operated at high atmospheric pressure to greenhouses operated at low pressure for three different lighting methods: natural, artificial and hybrid lighting. c2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

  2. Effects of physical agitation on yield of greenhouse-grown soybean

    Science.gov (United States)

    Jones, R. S.; Mitchell, C. A.

    1992-01-01

    Agronomic and horticultural crop species experience reductions in growth and harvestable yield after exposure to physical agitation (also known as mechanical stress), as by wind or rain. A greenhouse study was conducted to test the influence of mechanical stress on soybean yield and to determine if exposure to mechanical stress during discrete growth periods has differential effects on seed yield. A modified rotatory shaker was used to apply seismic (i.e., shaking) stress. Brief, periodic episodes of seismic stress reduced stem length, total seed dry weight, and seed number of soybean [Glycine max (L.) Merr.]. Lodging resistance was greater for plants stressed during vegetative growth or throughout vegetative and reproductive growth than during reproductive growth only. Seed dry weight yield was reduced regardless of the timing or duration of stress application, but was lowest when applied during reproductive development. Seismic stress applied during reproductive growth stages R1 to R2 (Days 3 to 4) was as detrimental to seed dry weight accumulation as was stress applied during growth stages R1 to R6 (Days 39 to 42). Seed dry weight per plant was highly correlated with seed number per plant, and seed number was correlated with the seed number of two- and three-seeded pods. Dry weight per 100 seeds was unaffected by seismic-stress treatment. Growth and yield reductions resulting from treatments applied only during the vegetative stage imply that long-term mechanical effects were induced, from which the plants did not fully recover. It is unclear which yield-controlling physiological processes were affected by mechanical stress. Both transient and long-term effects on yield-controlling processes remain to be elucidated.

  3. Integrated cost-effectiveness analysis of greenhouse gas emission abatement. The case of Finland

    Energy Technology Data Exchange (ETDEWEB)

    Lehtilae, A.; Tuhkanen, S. [VTT Energy, Espoo (Finland). Energy Systems

    1999-11-01

    In Finland greenhouse gas emissions are expected to increase during the next decades due to economic growth, particularly in the energy intensive industrial sectors. The role of these industries is very central in the national economy. The emission control according to the Kyoto Protocol will therefore be quite difficult and costly. The study analyses the cost-effectiveness of different technical options for reducing the emissions of carbon dioxide, methane, and nitrous oxide in Finland. The analysis is performed with the help of a comprehensive energy system model for Finland, which has been extended to cover all major sources of methane and nitrous oxide emissions in the energy sector, industry, waste management and agriculture. The focus being on technical options, no consideration is given to possible policy measures, emission trading or joint implementation in the study. Under the boundary conditions given for the development of the Finnish energy economy, cost-effective technical measures in the energy system include increases in the use of wood biomass, natural gas and wind energy, increases in the contribution of CHP to the power supply, and intensified energy conservation in all end-use sectors. Additional cost-effective measures are landfill gas recovery, utilisation of the combustible fraction of waste and catalytic conversion of N{sub 2}O in nitric acid production. With baseline assumptions, the direct annual costs of emission abatement are calculated to be about 2000 MFIM (330 M{epsilon}) in 2010. The marginal costs are estimated to be about 230 FIM (40 {epsilon}) per tonne of CO{sub 2}-equivalent in 2010. The cost curie derived from the analysis could be used in further analyses concerning emissions trading. (orig.) 109 refs. SIHTI Research Programme

  4. Pilot Greenhouse

    CERN Multimedia

    1983-01-01

    This pilot greenhouse was built in collaboration with the "Association des Maraichers" of Geneva in the frame of the study for making use of the heat rejected as warm water by CERN accelerators and experiments. Among other improvements, more automated and precise regulation systems for heating and ventilation were developed. See also 8305598X.

  5. Atmospheric Science: It's More than Meteorology.

    Science.gov (United States)

    Smith, David R.; Krockover, Gerald H.

    1988-01-01

    Indicates that atmospheric science is not just forcasting the weather. Gives an overview of current topics in meteorology including ozone depletion, acid precipitation, winter cyclones, severe local storms, the greenhouse effect, wind shear and microbursts. Outlines the Atmospheric Sciences Education Program at Purdue University to produce…

  6. Energy, atmospheric chemistry, and global climate

    Science.gov (United States)

    Levine, Joel S.

    1991-01-01

    Global atmospheric changes due to ozone destruction and the greenhouse effect are discussed. The work of the Intergovernmental Panel on Climate Change is reviewed, including its judgements regarding global warming and its recommendations for improving predictive capability. The chemistry of ozone destruction and the global atmospheric budget of nitrous oxide are reviewed, and the global sources of nitrous oxide are described.

  7. Effect of pest controlling neem and mata-raton leaf extracts on greenhouse gas emissions from urea-amended soil cultivated with beans: a greenhouse experiment.

    Science.gov (United States)

    Méndez-Bautista, Joaquín; Fernández-Luqueño, Fabián; López-Valdez, Fernando; Mendoza-Cristino, Reyna; Montes-Molina, Joaquín A; Gutierrez-Miceli, Federico A; Dendooven, L

    2010-10-01

    In a previous laboratory experiment, extracts of neem (Azadirachta indica A. Juss.) and Gliricidia sepium Jacquin, locally known as mata-raton, used to control pests on crops, inhibited emissions of CO(2) from a urea-amended soil, but not nitrification and N(2)O emissions. We investigated if these extracts when applied to beans (Phaseolus vulgaris L.) affected their development, soil characteristics and emissions of carbon dioxide (CO(2)) and nitrous oxide (N(2)O) in a greenhouse environment. Untreated beans and beans planted with lambda-cyhalothrin, a commercial insecticide, served as controls. After 117days, shoots of plants cultivated in soil amended with urea or treated with lambda-cyhalothrin, or extracts of neem or G. sepium were significantly higher than when cultivated in the unamended soil, while the roots were significantly longer when plants were amended with urea or treated with leaf extracts of neem or G. sepium than when treated with lambda-cyhalothrin. The number of pods, fresh and dry pod weight and seed yield was significantly higher when bean plants were treated with leaf extracts of neem or G. sepium treatments than when left untreated and unfertilized. The number of seeds was similar for the different treatments. The number of nodules was lower in plants fertilized with urea, treated with leaf extracts of neem or G. sepium, or with lambda-cyhalothrin compared to the unfertilized plants. The concentrations of NH(4)(+), NO(2)(-) and NO(3)(-) decreased significantly over time with the lowest concentrations generally found at harvest. Treatment had no significant effect on the concentrations of NH(4)(+) and NO(2)(-), but the concentration of NO(3)(-) was significantly lower in the unfertilized soil compared to the other treatments. It was found that applying extracts of neem or G. sepium leaves to beans favored their development when compared to untreated plants, but had no significant effect on nitrification in soil.

  8. Revisiting the Carrington Event: Updated modeling of atmospheric effects

    CERN Document Server

    Thomas, Brian C; Snyder, Brock R

    2011-01-01

    The terrestrial effects of major solar events such as the Carrington white-light flare and subsequent geomagnetic storm of August-September 1859 are of considerable interest, especially in light of recent predictions that such extreme events will be more likely over the coming decades. Here we present results of modeling the atmospheric effects, especially production of odd nitrogen compounds and subsequent depletion of ozone, by solar protons associated with the Carrington event. This study combines approaches from two previous studies of the atmospheric effect of this event. We investigate changes in NOy compounds as well as depletion of O3 using a two-dimensional atmospheric chemistry and dynamics model. Atmospheric ionization is computed using a range-energy relation with four different proxy proton spectra associated with more recent well-known solar proton events. We find that changes in atmospheric constituents are in reasonable agreement with previous studies, but effects of the four proxy spectra use...

  9. The social representations of the greenhouse effect (6. wave of questions); Les representations sociales de l'effet de serre (6. vague d'enquete)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    Six waves of questions concerning the public opinion of the greenhouse effect, were realized by the ISL in May 2000, March 2001, July 2002, June 2003 and May 2004. This sixth wave was realized between June 14 and 25 2005. The report presents the questions asked and analyzes the answers. The concerned domains are the greenhouse effect, the causes, the consequences, the greenhouse effect remediation (technical and political choices), the climatic change, the confidence on the actors and the institutions. (A.L.B.)

  10. Effects of exogenous abscisic acid on yield, antioxidant capacities, and phytochemical contents of greenhouse grown lettuces.

    Science.gov (United States)

    Li, Zheng; Zhao, Xin; Sandhu, Amandeep K; Gu, Liwei

    2010-05-26

    Antioxidants and phytochemicals in vegetables are known to provide health benefits. Strategies that enhance these properties are expected to increase the nutritional values of vegetables. The objective of this research is to assess the effects of exogenous abscisic acid (ABA) on yield, antioxidant capacities, and phytochemical content of lettuces grown in a greenhouse. Red loose leaf lettuce (cv. Galactic) and green loose leaf lettuce (cv. Simpson Elite) were cultivated using a randomized complete block design. Three concentrations of ABA in water [0 (control), 150, 300 ppm] were sprayed on the 30th and 39th days after sowing, and lettuces were harvested on the 46th day. Exogenous ABA significantly decreased yield of green and red lettuces. Total phenolic and total anthocyanin contents in red lettuce treated with ABA were significantly higher than in controls, whereas no significant differences were observed in green lettuce. ABA significantly induced the accumulation of chlorophyll b and total carotenoids in lettuces. The phenolic compounds identified and quantified in red and green lettuces included caffeoyltartaric acid, 5-O-caffeoylquinic acid, dicaffeoyltartaric acid, 3,5-dicaffeoylquinic acid, and quercetin 3-(6''-malonyl)-glucoside. Additionally, cyanidin 3-glucoside, cyanidin 3-(3''-malonoyl)-glucoside, and cyanidin 3-(6''-malonoyl)-glucoside in red lettuces were quantified. No significant effects of ABA on these individual phytochemicals were observed in green lettuces, whereas ABA significantly elevated the content of individual phytochemicals in red lettuces except for 5-O-caffeoylquinic acid. Differences among red lettuces with or without exogenous ABA were visualized on the score plots of principal component analyses. Loading plot indicated that multiple phenolic compounds contributed to the observed differences in red lettuces.

  11. [Effect of Biochar on Soil Greenhouse Gas Emissions in Semi-arid Region].

    Science.gov (United States)

    Guo, Yan-liang; Wang, Dan-dan; Zheng, Ji-yong; Zhao, Shi-wei; Zhang, Xing-chang

    2015-09-01

    This study aimed to investigate the effects of biochar addition on the emission of greenhouse gases from farmland soil in semi-arid region. Through an in-situ experiments, the influence of sawdust biochar(J) and locust tree skin biochar (H) at three doses (1%, 3%, and 5% of quality percentage) on C2, CH4 and N2O emissions were studied within the six months in the south of Ningxiaprovince. The results indicated that soil CO2 emission flux was slightly increased with the addition doses for both biochars, and the averaged CO2 emission flux for sawdust and locust tree skin biochar was enhanced by 1. 89% and 3. 34% compared to the control, but the difference between treatments was not statistically significant. The soil CH4 emission was decreased with the increasing of biochar doses, by 1. 17%, 2. 55%, 4. 32% for J1, J3, J5 and 2. 35%, 5. 83%, 7. 32% for H1, H3, H5, respectively. However, the difference was statistically significant only for J5, H3 and H5 treatments (P effect on soil N2O emission. Our study indicated that the biochar has no significant influence on soil CO2 and N2O emissions within six months in semi-arid region and can significantly influence soil CH4 emissions (P < 0. 05). As for biochar type, the locust tree skin biochar is significantly better than the sawdust biochar in terms of restraining CH4 emission(P = 0. 048).

  12. "Atmospheric Measurements by Ultra-Light SpEctrometer" (AMULSE) dedicated to vertical profile measurements of greenhouse gases (CO2, CH4) under stratospheric balloons: instrumental development and field application.

    Science.gov (United States)

    Maamary, Rabih; Joly, Lilian; Decarpenterie, Thomas; Cousin, Julien; Dumelié, Nicolas; Grouiez, Bruno; Albora, Grégory; Chauvin, Nicolas; Miftah-El-Khair, Zineb; Legain, Dominique; Tzanos, Diane; Barrié, Joel; Moulin, Eric; Ramonet, Michel; Bréon, François-Marie; Durry, Georges

    2016-04-01

    Human activities disrupt natural biogeochemical cycles such as the carbon and contribute to an increase in the concentrations of the greenhouse gases (carbone dioxide and methane) in the atmosphere. The current atmospheric transport modeling (the vertical trade) still represents an important source of uncertainty in the determination of regional flows of greenhouse gases, which means that a good knowledge of the vertical distribution of CO2 is necessary to (1) make the link between the ground measurements and spatial measurements that consider an integrated concentration over the entire column of the atmosphere, (2) validate and if possible improve CO2 transport model to make the link between surface emissions and observed concentration. The aim of this work is to develop a lightweight instrument (based on mid-infrared laser spectrometry principles) for in-situ measuring at high temporal/spatial resolution (5 Hz) the vertical profiles of the CO2 and the CH4 using balloons (meteorological and BSO at high precision levels (logistics flights. These laser spectrometers are built on recent instrumental developments. Several flights were successfully done in the region Champagne-Ardenne and in Canada recently. Aknowledgments: The authors acknowledge financial supports from CNES, CNRS défi instrumental and the region Champagne-Ardenne.

  13. CO2 Allowance Allocation in the Regional Greenhouse Gas Initiative and the Effect on Electricity Investors

    OpenAIRE

    Burtraw, Dallas; Palmer, Karen; Kahn, Daniel

    2005-01-01

    The Regional Greenhouse Gas Initiative (RGGI) is an effort by nine Northeast and Mid-Atlantic states to develop a regional, mandatory, market-based cap-and-trade program to reduce greenhouse gas (GHG) emissions from the electricity sector. The initiative is expected to lead to an increase in the price of electricity in the RGGI region and beyond. The implications of these changes for the value of electricity-generating assets and the market value of the firms that own them depends on the init...

  14. EFFECT OF SOIL SOLARIZATION ON THERMAL REGIME OF PLASTIC GREENHOUSE SOIL

    OpenAIRE

    Nereu Augusto Streck; Flavio Miguel Schneider; Galileo Adeli Buriol

    1994-01-01

    SUMMARY Temperature modification in soil of plastic greenhouse caused by solarization was measured during the summer in the Subtropical Central Region of the Rio Grande do Sul State, Brazil. The experiment was carried out in a 10m x 25m greenhouse covered with low density transparent polyethylene (PE). Four 6m x 4m plots were mulched with 100µm thickness PE sheets, from December 12, 1992 to March 7, 1993. Four other plots (same size) without the cover were used as control (bare soil). Results...

  15. No effect of cropping system on the greenhouse gas N2O

    DEFF Research Database (Denmark)

    Carter, Mette S.; Chirinda, Ngoni

    2009-01-01

    Organic farming is comparable to conventional in terms of field emissions of the strong greenhouse gas nitrous oxide (N2O). Our study points to the need for increased yields in organic farming as measure to reduced emissions per unit of produce.......Organic farming is comparable to conventional in terms of field emissions of the strong greenhouse gas nitrous oxide (N2O). Our study points to the need for increased yields in organic farming as measure to reduced emissions per unit of produce....

  16. Greenhouse effect: what are doing the Unites States; Effet de serre: ce que font les Etats-Unis

    Energy Technology Data Exchange (ETDEWEB)

    Quiret, M.

    2004-06-01

    Although they refuse to sign the kyoto protocol, the United States count on the new technologies and the industrialists participation to fight against the greenhouse effect. The author presents the local projects and initiatives (nine states of the north-east decided coordinated actions to fight the CO{sub 2} emissions) facing the increasing non commitment of the federal government. (A.L.B.)

  17. The ice-core record - Climate sensitivity and future greenhouse warming

    Science.gov (United States)

    Lorius, C.; Raynaud, D.; Jouzel, J.; Hansen, J.; Le Treut, H.

    1990-01-01

    The prediction of future greenhouse-gas-warming depends critically on the sensitivity of earth's climate to increasing atmospheric concentrations of these gases. Data from cores drilled in polar ice sheets show a remarkable correlation between past glacial-interglacial temperature changes and the inferred atmospheric concentration of gases such as carbon dioxide and methane. These and other palaeoclimate data are used to assess the role of greenhouse gases in explaining past global climate change, and the validity of models predicting the effect of increasing concentrations of such gases in the atmosphere.

  18. Greenhouse gas and soil nutrient dynamics at Haliburton Forest: nitrogen and phosphorous amendments to soils to study the effects of high nitrogen deposition

    Science.gov (United States)

    Winsborough, C. L.; Basiliko, N.

    2011-12-01

    Many of Canada's forests are currently experiencing a major environmental disturbance in the form of atmospheric nitrogen (N) deposition from fossil fuel burning and agricultural practices. Nitrogen is a major nutrient required for plants and soil microorganisms and is normally in short supply relative to biological demands. However, when N is in excess various negative impacts result including nutrient leaching, increased nitrous oxide (N2O) emissions, and disturbances to carbon and methane (CH4) cycling. Introducing soil amendments might have the potential to mitigate the negative impacts of excess N in forest soils. Previous research at Haliburton Forest in southeastern Ontario, Canada has demonstrated that N is no longer a limiting nutrient for plants, but rather phosphorous (P), where the addition of P resulted in rapid increased growth in sugar maple trees. We characterized long term (>5 years) and more immediate/short-term effects of P additions and short-term effects of N and N+P additions to soils at Haliburton Forest on the exchange of greenhouse gases (CH4, N2O, CO2) and cycling of N and P to determine the extent of excess N impact and potential N saturation. Long-term effects of P addition demonstrated suppressed levels of CH4 uptake likely due to an N limitation of CH4 oxidizing bacteria. Decreased pools of N with P addition suggest that P additions alleviate P limitation and induce N uptake, however overall low inorganic N pools suggest that N saturation has not yet appeared. Immediate effects demonstrated increased N2O and CO2 efflux and suppressed CH4 uptake in N amended plots while P amended plots remained similar to control plots. 1- and 2-year post-application greenhouse gas and nutrient data will help to elucidate these findings.

  19. Climate change and agroecosystems: the effect of elevated atmospheric CO2 and temperature on crop growth, development, and yield

    Directory of Open Access Journals (Sweden)

    Streck Nereu Augusto

    2005-01-01

    Full Text Available The amount of carbon dioxide (CO2 of the Earths atmosphere is increasing, which has the potential of increasing greenhouse effect and air temperature in the future. Plants respond to environment CO2 and temperature. Therefore, climate change may affect agriculture. The purpose of this paper was to review the literature about the impact of a possible increase in atmospheric CO2 concentration and temperature on crop growth, development, and yield. Increasing CO2 concentration increases crop yield once the substrate for photosynthesis and the gradient of CO2 concentration between atmosphere and leaf increase. C3 plants will benefit more than C4 plants at elevated CO2. However, if global warming will take place, an increase in temperature may offset the benefits of increasing CO2 on crop yield.

  20. Atmospheric dispersion effects in weak lensing measurements

    CERN Document Server

    Plazas, Andrés A

    2012-01-01

    The wavelength dependence of atmospheric refraction causes elongation of finite-bandwidth images along the elevation vector, which produces spurious signals in weak gravitational lensing shear measurements unless this atmospheric dispersion is calibrated and removed to high precision. Because astrometric solutions and point spread function (PSF) characteristics are typically calibrated from stellar images, differences between the reference stars' spectra and the galaxies' spectra will leave residual errors in both the astrometric positions ($\\Delta{\\bar{R}}$) and in the second moment (width) of the wavelength-averaged PSF ($\\Delta{v}$) for galaxies. We estimate the level of $\\Delta{V}$ that will induce spurious weak lensing signals in PSF-corrected galaxy shapes that exceed the statistical errors of the {\\em Dark Energy Survey (DES)} and the {\\em Large Synoptic Survey Telescope (LSST)} cosmic-shear experiments. We also estimate the $\\Delta{\\bar{R}}$ signals that will produce unacceptable spurious distortions ...

  1. Effects of Continuous Tomato Monoculture on Soil Microbial Properties and Enzyme Activities in a Solar Greenhouse

    Directory of Open Access Journals (Sweden)

    Hongdan Fu

    2017-02-01

    Full Text Available Soil-related obstacles resulting from continuous monoculture have limited the sustainable development of the tomato industry in China. An experiment on tomatoes with seven continuous monoculture treatments (the 1st, 3rd, 5th, 7th, 9th, 11th, and 13th crops, respectively was conducted in a solar greenhouse, to investigate the influence of monoculture on soil quality. Most soil quality indicators first increased and then decreased with increasing continuous monoculture crops, and significant differences among crops were observed. Indicators at the 13th crop were significantly lower than those at the other crops in terms of average well color development (AWCD, substrate richness (S, the Shannon diversity index (H, and the McIntosh index (U of the soil microbial community (SMC, soil urease (UR, and neutral phosphatase (N-PHO activities, and available nitrogen (AN and potassium (AK. However, fungal abundance (FUN at the 13th crop was significantly higher than that at the other crops. As principal component analysis (PCA revealed, SMC functional diversity at the 1st, 11th, and 13th crops were similar, and were obviously distinguished from those at the other crops. Moreover, the tomato yield was significantly and positively correlated with soil-available potassium and SMC functional diversity indexes. Our findings indicated that short-term continuous monoculture, e.g., for fewer than seven or nine crops, was beneficial for soil quality improvement. However, continuous monoculture for greater than 11 crops had adverse effects on soil enzyme activities, soil microbial abundances, soil chemical properties, soil SMC functional diversity, and the tomato yield, particularly at the 13th crop.

  2. The effect of agency budgets on minimizing greenhouse gas emissions from road rehabilitation policies

    Science.gov (United States)

    Reger, Darren; Madanat, Samer; Horvath, Arpad

    2015-11-01

    Transportation agencies are being urged to reduce their greenhouse gas (GHG) emissions. One possible solution within their scope is to alter their pavement management system to include environmental impacts. Managing pavement assets is important because poor road conditions lead to increased fuel consumption of vehicles. Rehabilitation activities improve pavement condition, but require materials and construction equipment, which produce GHG emissions as well. The agency’s role is to decide when to rehabilitate the road segments in the network. In previous work, we sought to minimize total societal costs (user and agency costs combined) subject to an emissions constraint for a road network, and demonstrated that there exists a range of potentially optimal solutions (a Pareto frontier) with tradeoffs between costs and GHG emissions. However, we did not account for the case where the available financial budget to the agency is binding. This letter considers an agency whose main goal is to reduce its carbon footprint while operating under a constrained financial budget. A Lagrangian dual solution methodology is applied, which selects the optimal timing and optimal action from a set of alternatives for each segment. This formulation quantifies GHG emission savings per additional dollar of agency budget spent, which can be used in a cap-and-trade system or to make budget decisions. We discuss the importance of communication between agencies and their legislature that sets the financial budgets to implement sustainable policies. We show that for a case study of Californian roads, it is optimal to apply frequent, thin overlays as opposed to the less frequent, thick overlays recommended in the literature if the objective is to minimize GHG emissions. A promising new technology, warm-mix asphalt, will have a negligible effect on reducing GHG emissions for road resurfacing under constrained budgets.

  3. Potential effects of clean coal technologies on acid precipitation, greenhouse gases, and solid waste disposal

    Energy Technology Data Exchange (ETDEWEB)

    Blasing, T.J.; Miller, R.L.; McCold, L.N.

    1993-11-01

    The US Department of Energy`s (DOE`s) Clean Coal Technology Demonstration Program (CCTDP) was initially funded by Congress to demonstrate more efficient, economically feasible, and environmentally acceptable coal technologies. Although the environmental focus at first was on sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) because their relationship to acid precipitation, the CCTDP may also lead to reductions in carbon dioxide (CO{sub 2}) emissions and in the volume of solid waste produced, compared with conventional technologies. The environmental effects of clean coal technologies (CCTs) depend upon which (if any) specific technologies eventually achieve high acceptance in the marketplace. In general, the repowering technologies and a small group of retrofit technologies show the most promise for reducing C0{sub 2} emissions and solid waste. These technologies also compare favorably with other CCTs in terms of SO{sub 2} and NO{sub x} reductions. The upper bound for CO{sup 2} reductions in the year 2010 is only enough to reduce global ``greenhouse`` warming potential by about 1%. However, CO{sub 2} emissions come from such variety of sources around the globe that no single technological innovation or national policy change could realistically be expected to reduce these emissions by more than a few percent. Particular CCTs can lead to either increases or decreases in the amount of solid waste produced. However, even if decreases are not achieved, much of the solid waste from clean coal technologies would be dry and therefore easier to dispose of than scrubber sludge.

  4. [Effects of antiseptic on the analysis of greenhouse gases concentrations in lake water].

    Science.gov (United States)

    Xiao, Qi-Tao; Hu, Zheng-Hu; James, Deng; Xiao, Wei; Liu, Shou-Dong; Li, Xu-Hui

    2014-01-01

    To gain insight into antiseptic effects on the concentrations of CO2, CH4, and N2O in lake water, antisepetic (CuSO4 and HgCl2) were added into water sample, and concentrations of greenhouse gases were measured by the gas chromatography based on water equilibrium method. Experiments were conducted as following: the control group without antisepetic (CK), the treatment group with 1 mL CuSO4 solution (T1), the treatment group with 5 mL CuSO4 solution (T2), and the treatment group with 0.5 mL HgCl2 solution (T3). All groups were divided into two batches: immediately analysis (I), and after 2 days analysis (II). Results showed that CuSO4 and HgCl2 significantly increased CO2 concentration, the mean CO2 concentration (Mco2) of CK (I) and CK (II) were (11.5 +/- 1.47) micromol x L(-1) and (14.38 +/- 1.59) micromol x L(-1), respectively; the Mco2 of T1 (I) and T1 (II) were (376 +/- 70) micromol x L(-1) and (448 +/- 246.83) micromol x L(-1), respectively; the Mco2 of T2 (I) and T2 (II) were (885 +/- 51.53) micromol x L(-1) and (988.83 +/- 101.96) micromol x L(-1), respectively; the Mco2 of T3 (I) and T3 (II) were (287.19 +/- 30.01) micromol x L(-1) and (331.33 +/- 22.06) micromol x L(-1), respectively. The results also showed that there was no difference in CH4 and N2O concentrations among treatments. Water samples should be analyzed as soon as possible after pretreatment. Our findings suggest that adding antiseptic may lead an increase in CO2 concentration.

  5. Carbon sequestration and greenhouse gases emissions in soil under sewage sludge residual effects

    Directory of Open Access Journals (Sweden)

    Leonardo Machado Pitombo

    2015-02-01

    Full Text Available The large volume of sewage sludge (SS generated with high carbon (C and nutrient content suggests that its agricultural use may represent an important alternative to soil carbon sequestration and provides a potential substitute for synthetic fertilizers. However, emissions of CH4 and N2O could neutralize benefits with increases in soil C or saving fertilizer production because these gases have a Global Warming Potential (GWP 25 and 298 times greater than CO2, respectively. Thus, this study aimed to determine C and N content as well as greenhouse gases (GHG fluxes from soils historically amended with SS. Sewage sludge was applied between 2001 and 2007, and maize (Zea mays L. was sowed in every year between 2001 and 2009. We evaluated three treatments: Control (mineral fertilizer, 1SS (recommended rate and 2SS (double rate. Carbon stocks (0-40 cm were 58.8, 72.5 and 83.1 Mg ha–1in the Control, 1SS and 2SS, respectively, whereas N stocks after two years without SS treatment were 4.8, 5.8, and 6.8 Mg ha–1, respectively. Soil CO2 flux was highly responsive to soil temperature in SS treatments, and soil water content greatly impacted gas flux in the Control. Soil N2O flux increased under the residual effects of SS, but in 1SS, the flux was similar to that found in moist tropical forests. Soil remained as a CH4sink. Large stores of carbon following historical SS application indicate that its use could be used as a method for carbon sequestration, even under tropical conditions.

  6. PROTOTYPE TOOL FOR EVALUATING THE COST AND EFFECTIVENESS OF GREENHOUSE GAS MITIGATION TECHNOLOGIES

    Science.gov (United States)

    The paper introduces the structure of a tool, being developed by the U.S. EPA's Office of Research and Development, that will be able to analyze the benefits of new technologies and strategies for controlling greenhouse gas (GHG) emissions. When completed, the tool will be able ...

  7. The Effect of New Developed Fluorescent Greenhouse Films on the Growth of Fragaria x ananassa 'Elsanta'

    NARCIS (Netherlands)

    Hemming, S.; Os, van E.A.; Hemming, J.; Dieleman, J.A.

    2006-01-01

    In order to optimise light quality and quantity for plant growth, new photoselective greenhouse covering materials were developed containing different fluorescent pigments (Blue, Red1, Red2, Red3) in different concentrations. Excitation of all fluorescent pigments took place around 365 nm. Blue pigm

  8. The effect of food consumption and production trends on energy, greenhouse gas emissions and land use

    NARCIS (Netherlands)

    Birkett, D.; Patel, M.K.

    2008-01-01

    In this report we assess the trends in food consumption and food-related environmental impacts (in terms of energy use, greenhouse gas emissions and land use) for three regions: Western Europe, the USA and China. The environmental impacts were determined by two methods: a product level analysis, in

  9. Mitigation of greenhouse gas emissions from reed canary grass in paludiculture: effect of groundwater level

    DEFF Research Database (Denmark)

    Karki, Sandhya; Elsgaard, Lars; Audet, Joachim

    2014-01-01

    Background and aims Combination of rewetting and wetland crop cultivation (paludiculture) is pursued as a wider carbon dioxide (CO2) mitigation option in drained peatland. However, information on the overall greenhouse gas (GHG) balance for paludiculture is lacking. We investigated the GHG balance...

  10. Assessment of the greenhouse effect impact of technologies used for energy recovery from municipal waste: a case for England.

    Science.gov (United States)

    Papageorgiou, A; Barton, J R; Karagiannidis, A

    2009-07-01

    Waste management activities contribute to global greenhouse gas emissions approximately by 4%. In particular the disposal of waste in landfills generates methane that has high global warming potential. Effective mitigation of greenhouse gas emissions is important and could provide environmental benefits and sustainable development, as well as reduce adverse impacts on public health. The European and UK waste policy force sustainable waste management and especially diversion from landfill, through reduction, reuse, recycling and composting, and recovery of value from waste. Energy from waste is a waste management option that could provide diversion from landfill and at the same time save a significant amount of greenhouse gas emissions, since it recovers energy from waste which usually replaces an equivalent amount of energy generated from fossil fuels. Energy from waste is a wide definition and includes technologies such as incineration of waste with energy recovery, or combustion of waste-derived fuels for energy production or advanced thermal treatment of waste with technologies such as gasification and pyrolysis, with energy recovery. The present study assessed the greenhouse gas emission impacts of three technologies that could be used for the treatment of Municipal Solid Waste in order to recover energy from it. These technologies are Mass Burn Incineration with energy recovery, Mechanical Biological Treatment via bio-drying and Mechanical Heat Treatment, which is a relatively new and uninvestigated method, compared to the other two. Mechanical Biological Treatment and Mechanical Heat Treatment can turn Municipal Solid Waste into Solid Recovered Fuel that could be combusted for energy production or replace other fuels in various industrial processes. The analysis showed that performance of these two technologies depends strongly on the final use of the produced fuel and they could produce GHG emissions savings only when there is end market for the fuel. On the

  11. Efficiency of energy recovery from municipal solid waste and the resultant effect on the greenhouse gas balance.

    Science.gov (United States)

    Gohlke, Oliver

    2009-11-01

    Global warming is a focus of political interest and life-cycle assessment of waste management systems reveals that energy recovery from municipal solid waste is a key issue. This paper demonstrates how the greenhouse gas effects of waste treatment processes can be described in a simplified manner by considering energy efficiency indicators. For evaluation to be consistent, it is necessary to use reasonable system boundaries and to take the generation of electricity and the use of heat into account. The new European R1 efficiency criterion will lead to the development and implementation of optimized processes/systems with increased energy efficiency which, in turn, will exert an influence on the greenhouse gas effects of waste management in Europe. Promising technologies are: the increase of steam parameters, reduction of in-plant energy consumption, and the combined use of heat and power. Plants in Brescia and Amsterdam are current examples of good performance with highly efficient electricity generation. Other examples of particularly high heat recovery rates are the energy-from-waste (EfW) plants in Malmö and Gothenburg. To achieve the full potential of greenhouse gas reduction in waste management, it is necessary to avoid landfilling combustible wastes, for example, by means of landfill taxes and by putting incentives in place for increasing the efficiency of EfW systems.

  12. [Treatment effect of biological filtration and vegetable floating-bed combined system on greenhouse turtle breeding wastewater].

    Science.gov (United States)

    Chen, Chong-Jun; Zhang, Rui; Xiang, Kun; Wu, Wei-Xiang

    2014-08-01

    Unorganized discharge of greenhouse turtle breeding wastewater has brought several negative influences on the ecological environment in the rural area of Yangtze River Delta. Biological filtration and vegetable floating-bed combined system is a potential ecological method for greenhouse turtle breeding wastewater treatment. In order to explore the feasibility of this system and evaluate the contribution of vegetable uptake of nitrogen (N) and phosphorus (P) in treating greenhouse turtle breeding wastewater, three types of vegetables, including Ipomoea aquatica, lettuce and celery were selected in this study. Results showed the combined system had a high capacity in simultaneous removal of organic matter, N and P. The removal efficiencies of COD, NH4(+)-N, TN and TP from the wastewater reached up to 93.2%-95.6%, 97.2%-99.6%, 73.9%-93.1% and 74.9%-90.0%, respectively. System with I. aquatica had the highest efficiencies in N and P removal, followed by lettuce and celery. However, plant uptake was not the primary pathway for TN arid TP removal in the combined system. The vegetable uptake of N and P accounted for only 9.1%-25.0% of TN and TP removal from the wastewater while the effect of microorganisms would be dominant for N and P removal. In addition, the highest amounts of N and P uptake in I. aquatica were closely related with the biomass of plant. Results from the study indicated that the biological filtration and vegetable floating-bed combined system was an effective approach to treating greenhouse turtle breeding wastewater in China.

  13. Knowledge about the Greenhouse Effect and the Effects of the Ozone Layer among Norwegian Pupils Finishing Compulsory Education in 1989, 1993, and 2005--What Now?

    Science.gov (United States)

    Hansen, Pal J. Kirkeby

    2010-01-01

    The greenhouse effect and the effects of the ozone layer have been in the media and public focus for more than two decades. During the same period, Norwegian compulsory schools have had four national curricula. The two last-mentioned prescribe explicitly the two topics. Media and public discourse might have been sources of information causing…

  14. Influence of Sea Surface Temperature, Tropospheric Humidity and Lapse Rate on the Annual Cycle of the Clear-Sky Greenhouse Effect

    Science.gov (United States)

    Hu, H.; Liu, W.

    2000-01-01

    The implication of this work will provide modeling study a surrogate of annual cycle of the greenhouse effect. For example, the model should be able to simulate the annual cycle before it can be used for global change study.

  15. Role of Pakistan in Global Climate Change through Greenhouse Gas Emissions (GHGs)

    OpenAIRE

    Wajeeha Malik; Hajra Shahid; Rabeea Zafar; Zaheer Uddin; Zafar Wazir; Zubair Anwar; Jabar Zaman Khan Khattak; Syed Shahid Ali

    2012-01-01

    The increasing concentration of Greenhouse Gases (GHGs) is warming the earth’s atmosphere and the phenomenon is known as Climate Change or Global Warming. The major factors contributing to the global climate change include polluted emissions by excessive burning of fossil fuels and deforestation. Pakistan contributes very little to the overall Greenhouse Gas (GHG) emissions however it remains severely impacted by the negative effects of climate change. Pakistan, in particular is estimated to ...

  16. Co-effect of increased humidity and meteorological conditions on greenhouse gas fluxes in a young hybrid aspen forest

    Science.gov (United States)

    Hansen, Raili; Mander, Ülo; Kupper, Priit; Soosaar, Kaido; Maddison, Martin; Sõber, Jaak; Lõhmus, Krista

    2014-05-01

    Due to the climate change, higher precipitation and an increase in air humidity is expected in northern Europe in the near future (IPCC 2007). There are some studies about irrigation, elevated CO2 and O3 etc., but still we have too little knowledge about the humidity effect on the deciduous forest ecosystem. In 2006 a free-air humidity manipulation (FAHM) facility was established in Estonia and in 2008 we started to artificially increase the air humidity in young hybrid aspen (Populus tremula L. x P. tremuloides Michx.) forest trials on an Endogleyic Planosol of former arable land. Air humidity was raised on average about 7% compared to ambient condition (Tullus et al., 2012). We measured the carbon dioxide, methane and nitrous oxide fluxes from the FAHM system using closed static chamber and gas-chromatograph techniques from July 2009 to November 2012 during snow free periods. Flux measurements were done once a month in three humidification (h) plots and in three control (c) plots. We monitored soil temperature, soil water potential (SWP), precipitation and relative humidity. The vegetation period was rainy in 2009, droughty in 2010 and 2011 (according to SWP the drought was severe in 2011) and cold in 2012. Soil respiration was the lowest in 2011 both in c and h plots; however it was significantly higher in h. Most of the time the soil was a sink for methane, but less CH4 was oxidized in the soil of h plots. Emission of N2O did not have good correlation with air humidity, although one could observe a clear tendency of bigger N2O fluxes when soil was continuously water-saturated. Expectedly, soil respiration had strong positive correlations with soil temperature and CH4 emission demonstrated strong positive correlation with SWP. Hence, interaction of humidification and precipitation affected greenhouse gas fluxes. IPCC, Climate Change 2007: The Physical Science Basis. Cambridge University Press, Cambridge. 2007. Tullus A, Kupper P, Sellin A, Parts L, Sõber J

  17. Effect of pest controlling neem and mata-raton leaf extracts on greenhouse gas emissions from urea-amended soil cultivated with beans: A greenhouse experiment

    Energy Technology Data Exchange (ETDEWEB)

    Mendez-Bautista, Joaquin [Laboratory of Soil Ecology, Cinvestav, Mexico D.F. (Mexico); Fernandez-Luqueno, Fabian [Laboratory of Soil Ecology, Cinvestav, Mexico D.F. (Mexico); Department of Electromechanics, Renewable Energy Engineering, UTTulancingo, Hidalgo (Mexico); Lopez-Valdez, Fernando [Laboratory of Soil Ecology, Cinvestav, Mexico D.F. (Mexico); C.I.B.A.-I.P.N., Tepetitla de Lardizabal, Tlaxcala (Mexico); Mendoza-Cristino, Reyna [Laboratory of Soil Ecology, Cinvestav, Mexico D.F. (Mexico); Montes-Molina, Joaquin A.; Gutierrez-Miceli, Federico A. [Laboratorio de Biotecnologia Vegetal, Instituto Tecnologico de Tuxtla-Gutierrez, Tuxtla-Gutierrez (Mexico); Dendooven, L., E-mail: dendoove@cinvestav.mx [Laboratory of Soil Ecology, Cinvestav, Mexico D.F. (Mexico)

    2010-10-01

    In a previous laboratory experiment, extracts of neem (Azadirachta indica A. Juss.) and Gliricidia sepium Jacquin, locally known as mata-raton, used to control pests on crops, inhibited emissions of CO{sub 2} from a urea-amended soil, but not nitrification and N{sub 2}O emissions. We investigated if these extracts when applied to beans (Phaseolus vulgaris L.) affected their development, soil characteristics and emissions of carbon dioxide (CO{sub 2}) and nitrous oxide (N{sub 2}O) in a greenhouse environment. Untreated beans and beans planted with lambda-cyhalothrin, a commercial insecticide, served as controls. After 117 days, shoots of plants cultivated in soil amended with urea or treated with lambda-cyhalothrin, or extracts of neem or G. sepium were significantly higher than when cultivated in the unamended soil, while the roots were significantly longer when plants were amended with urea or treated with leaf extracts of neem or G. sepium than when treated with lambda-cyhalothrin. The number of pods, fresh and dry pod weight and seed yield was significantly higher when bean plants were treated with leaf extracts of neem or G. sepium treatments than when left untreated and unfertilized. The number of seeds was similar for the different treatments. The number of nodules was lower in plants fertilized with urea, treated with leaf extracts of neem or G. sepium, or with lambda-cyhalothrin compared to the unfertilized plants. The concentrations of NH{sub 4}{sup +}, NO{sub 2}{sup -} and NO{sub 3}{sup -} decreased significantly over time with the lowest concentrations generally found at harvest. Treatment had no significant effect on the concentrations of NH{sub 4}{sup +} and NO{sub 2}{sup -}, but the concentration of NO{sub 3}{sup -} was significantly lower in the unfertilized soil compared to the other treatments. It was found that applying extracts of neem or G. sepium leaves to beans favored their development when compared to untreated plants, but had no significant

  18. Greenhouse Gas Emissions From Cattle

    Directory of Open Access Journals (Sweden)

    Podkówka Zbigniew

    2015-03-01

    Full Text Available Cattle produce greenhouse gases (GHG which lead to changes in the chemical composition of the atmosphere. These gases which cause greenhouse effect include: methane (CH4, nitrous oxide (N2O, nitrogen oxides (NOx, sulphur dioxide (SO2, ammonia (NH3, dust particles and non-methane volatile organic compounds, commonly described as other than methane hydrocarbons. Fermentation processes taking place in the digestive tract produce ‘digestive gases’, distinguished from gases which are emitted during the decomposition of manure. Among these digestive gases methane and non-methane volatile organic compounds are of particular relevance importance. The amount of gases produced by cows can be reduced by choosing to rear animals with an improved genetically based performance. A dairy cow with higher production efficiency, producing milk with higher protein content and at the same time reduced fat content emits less GHG into the environment. Increasing the ratio of feed mixtures in a feed ration also reduces GHG emissions, especially of methane. By selection of dairy cows with higher production efficiency and appropriate nutrition, the farm's expected milk production target can be achieved while at the same time, the size of the herd is reduced, leading to a reduction of GHG emissions.

  19. The effect of lactation length on greenhouse gas emissions from the national dairy herd.

    Science.gov (United States)

    Wall, E; Coffey, M P; Pollott, G E

    2012-11-01

    Many governments have signed up to greenhouse gas emission (GHGE) reduction programmes under their national climate change obligations. Recently, it has been suggested that the use of extended lactations in dairy herds could result in reduced GHGE. Dairy GHGE were modelled on a national basis and the model was used to compare emissions from lactations of three different lengths (305, 370 and 440 days), and a current 'base' scenario on the basis of maintaining current milk production levels. In addition to comparing GHGE from the average 'National Herd' under these scenarios, results were used to investigate how accounting for lactations of different lengths might alter the estimation of emissions calculated from the National Inventory methodology currently recommended by Intergovernmental Panel on Climate Change. Data for the three lactation length scenarios were derived from nationally recorded dairy performance information and used in the GHGE model. Long lactations required fewer milking cows and replacements to maintain current milk yield levels than short ones, but GHGEs were found to rise from 1214 t of CO2 equivalent (CE)/farm per year for lactations of 305 days to 1371 t CE/farm per year for 440-day lactations. This apparent anomaly can be explained by the less efficient milk production (kg milk produced per kg cow weight) found in later lactation, a more pronounced effect in longer lactations. The sensitivity of the model to changes in replacement rate, persistency and level of milk yield was investigated. Changes in the replacement rate from 25% to 20% and in persistency by −10% to +20% resulted in very small changes in GHGE. Differences in GHGE due to the level of milk yield were much more dramatic with animals in the top 10% for yield, producing about 25% less GHGE/year than the average animal. National Inventory results were investigated using a more realistic spread of lactation lengths than recommended for such calculations using emissions

  20. Management of gas releases with greenhouse effect: which economical tools?; Maitriser les emissions de gaz a effet de serre: quels instruments economiques?

    Energy Technology Data Exchange (ETDEWEB)

    Lepeltier, Serge [Senat, Paris (France)

    2000-06-09

    The climatic change represents the most severe danger to the durable world development, public health and future prosperity. This document concerning the gas releases with greenhouse effect is a report of the Senate Planning delegation regarding the economic and fiscal tools envisaging abatement of releases of gases with greenhouse effect. These issues are presented in four chapters titled as follows: 1. Since the scientific evidencing, requirement of managing the releases of gas with greenhouse effect has been unanimously recognized at the summits of Rio (1992) and Kyoto (1997); 2. The economic theory suggests instruments for reducing the gas releases with greenhouse effect at a minimum cost; 3. Challenges and ways of international cooperation in the field of climatic change; 4. Joining the political will with the pragmatic use of the economic instruments at national scale. The document contains a synthesis of proposals directed towards the following goals: international negotiations relating to climatic change; creating the community framework of managing the gas releases resulting in greenhouse effect; establishing national measures for managing the gas releases leading to greenhouse effect; actions to be undertaken by the territorial collectivities.

  1. Memory efficient atmospheric effects modeling for infrared scene generators

    Science.gov (United States)

    Kavak, Çaǧlar; Özsaraç, Seçkin

    2015-05-01

    The infrared (IR) energy radiated from any source passes through the atmosphere before reaching the sensor. As a result, the total signature captured by the IR sensor is significantly modified by the atmospheric effects. The dominant physical quantities that constitute the mentioned atmospheric effects are the atmospheric transmittance and the atmospheric path radiance. The incoming IR radiation is attenuated by the transmittance and path radiance is added on top of the attenuated radiation. In IR scene simulations OpenGL is widely used for rendering purposes. In the literature there are studies, which model the atmospheric effects in an IR band using OpenGLs exponential fog model as suggested by Beers law. In the standard pipeline of OpenGL, the related fog model needs single equivalent OpenGL variables for the transmittance and path radiance, which actually depend on both the distance between the source and the sensor and also on the wavelength of interest. However, in the conditions where the range dependency cannot be modeled as an exponential function, it is not accurate to replace the atmospheric quantities with a single parameter. The introduction of OpenGL Shading Language (GLSL) has enabled the developers to use the GPU more flexible. In this paper, a novel method is proposed for the atmospheric effects modeling using the least squares estimation with polynomial fitting by programmable OpenGL shader programs built with GLSL. In this context, a radiative transfer model code is used to obtain the transmittance and path radiance data. Then, polynomial fits are computed for the range dependency of these variables. Hence, the atmospheric effects model data that will be uploaded in the GPU memory is significantly reduced. Moreover, the error because of fitting is negligible as long as narrow IR bands are used.

  2. Food, land and greenhouse gases The effect of changes in UK food consumption on land requirements and greenhouse gas emissions. Report for the Committee on Climate Change.

    OpenAIRE

    Audsley, Eric; Angus, Andrew; Chatterton, Julia C.; Graves, Anil R.; Morris, Joe; Murphy-Bokern,Donal; Pearn, Kerry R.; Daniel L Sandars; Williams, Adrian G.

    2010-01-01

    EXECUTIVE SUMMARY •1. Key findingsThis study examines the land use and greenhouse gas implications of UK food consumption change away from carbon intensive products. It shows that the UK agricultural land base can support increased consumption of plant-based products arising from the reduced consumption of livestock products. A 50% reduction in livestock product consumption reduces the area of arable and grassland required to supply UK food, both in the UK and overseas. It a...

  3. Effects of land use on greenhouse gas fluxes and soil properties of wetland catchments in the Prairie Pothole Region of North America

    Energy Technology Data Exchange (ETDEWEB)

    Tangen, Brian A., E-mail: btangen@usgs.gov; Finocchiaro, Raymond G., E-mail: rfinocchiaro@usgs.gov; Gleason, Robert A., E-mail: rgleason@usgs.gov

    2015-11-15

    Wetland restoration has been suggested as policy goal with multiple environmental benefits including enhancement of atmospheric carbon sequestration. However, there are concerns that increased methane (CH{sub 4}) emissions associated with restoration may outweigh potential benefits. A comprehensive, 4-year study of 119 wetland catchments was conducted in the Prairie Pothole Region of the north-central U.S. to assess the effects of land use on greenhouse gas (GHG) fluxes and soil properties. Results showed that the effects of land use on GHG fluxes and abiotic soil properties differed with respect to catchment zone (upland, wetland), wetland classification, geographic location, and year. Mean CH{sub 4} fluxes from the uplands were predictably low (< 0.02 g CH{sub 4} m{sup −2} day{sup −1}), while wetland zone CH{sub 4} fluxes were much greater (< 0.001–3.9 g CH{sub 4} m{sup −2} day{sup −1}). Mean cumulative seasonal CH{sub 4} fluxes ranged from roughly 0–650 g CH{sub 4} m{sup −2}, with an overall mean of approximately 160 g CH{sub 4} m{sup −2}. These maximum cumulative CH{sub 4} fluxes were nearly 3 times as high as previously reported in North America. The overall magnitude and variability of N{sub 2}O fluxes from this study (< 0.0001–0.0023 g N{sub 2}O m{sup −2} day{sup −1}) were comparable to previously reported values. Results suggest that soil organic carbon is lost when relatively undisturbed catchments are converted for agriculture, and that when non-drained cropland catchments are restored, CH{sub 4} fluxes generally are not different than the pre-restoration baseline. Conversely, when drained cropland catchments are restored, CH{sub 4} fluxes are noticeably higher. Consequently, it is important to consider the type of wetland restoration (drained, non-drained) when assessing restoration benefits. Results also suggest that elevated N{sub 2}O fluxes from cropland catchments likely would be reduced through restoration. The overall

  4. Assessing uncertainty in the cost-effectiveness of agricultural greenhouse gas mitigation

    OpenAIRE

    Eory, Vera; Topp, Cairistiona F.E.; Moran, Dominic; Butler, Adam

    2014-01-01

    Information on the uncertainty of quantitative results feeding into public decision making is essential for designing robust policies. However, this information is often not available in relation to the economics of greenhouse gas (GHG) mitigation in agriculture. This paper analyses the uncertainty of the mitigation estimates provided by a Marginal Abatement Cost Curve (MACC). The case study is based on the GHG MACC developed for Scottish agricultural soils. The qualitative assessment disenta...

  5. Has Human Society Passed a Tipping Point for Effective Reduction of Greenhouse Gas Emissions?

    OpenAIRE

    Cairns, John

    2010-01-01

    Recent publications have indicated that a 2 C increase of global average temperature, once thought acceptable, may involve serious risks (Greg, 2004). A global mean tempurature increase of 4 C would be hotter than any time in the last 30 million years, and this increase could be realized as early as 2060-2070 (Leahy, 2009). The prospects of plans for major, immediate reduction of anthropogenic greenhouse gas emissions at the climate onference at Copenhagen in December 2009 do not seem likely....

  6. Greenhouse gas policy influences climate via direct effects of land-use change

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Andrew D.; Collins, William D.; Edmonds, James A.; Torn, Margaret S.; Janetos, Anthony C.; Calvin, Katherine V.; Thomson, Allison M.; Chini, Louise M.; Mao, Jiafu; Shi, Xiaoying; Thornton, Peter; Hurtt, George; Wise, Marshall A.

    2013-06-01

    Proposed climate mitigation measures do not account for direct biophysical climate impacts of land-use change (LUC), nor do the stabilization targets modeled for the 5th Climate Model Intercomparison Project (CMIP5) Representative Concentration Pathways (RCPs). To examine the significance of such effects on global and regional patterns of climate change, a baseline and alternative scenario of future anthropogenic activity are simulated within the Integrated Earth System Model, which couples the Global Change Assessment Model, Global Land-use Model, and Community Earth System Model. The alternative scenario has high biofuel utilization and approximately 50% less global forest cover compared to the baseline, standard RCP4.5 scenario. Both scenarios stabilize radiative forcing from atmospheric constituents at 4.5 W/m2 by 2100. Thus, differences between their climate predictions quantify the biophysical effects of LUC. Offline radiative transfer and land model simulations are also utilized to identify forcing and feedback mechanisms driving the coupled response. Boreal deforestation is found to strongly influence climate due to increased albedo coupled with a regional-scale water vapor feedback. Globally, the alternative scenario yields a 21st century warming trend that is 0.5 °C cooler than baseline, driven by a 1 W/m2 mean decrease in radiative forcing that is distributed unevenly around the globe. Some regions are cooler in the alternative scenario than in 2005. These results demonstrate that neither climate change nor actual radiative forcing are uniquely related to atmospheric forcing targets such as those found in the RCP’s, but rather depend on particulars of the socioeconomic pathways followed to meet each target.

  7. Greenhouse Gases

    Science.gov (United States)

    ... life. Governments all around the world ban and control production and use of several industrial gases that destroy atmospheric ozone and create a hole in the ozone layer . At lower elevations of the atmosphere (the troposphere), ozone is harmful to ... for Future Emissions FAQs How much carbon dioxide is produced when ...

  8. Effects of agrochemicals, ultra violet stabilisers and solar radiation on the radiometric properties of greenhouse films

    Directory of Open Access Journals (Sweden)

    Giuliano Vox

    2013-10-01

    Full Text Available Agrochemicals, based on iron, sulphur and chlorine, generate by products that lead to a degradation of greenhouse films together with a decrease in their mechanical and physical properties. The degradation due to agrochemicals depends on their active principles, method and frequency of application, and greenhouse ventilation. The aim of the research was to evaluate how agrochemical contamination and solar radiation influence the radiometric properties of ethylene-vinyl acetate copolymer greenhouse films by means of laboratory and field tests. The films, manufactured on purpose with the addition of different light stabiliser systems, were exposed to natural outdoor weathering at the experimental farm of the University of Bari (Italy; 41° 05’ N in the period from 2006 to 2008. Each film was tested for two low tunnels: one low tunnel was sprayed from inside with the agrochemicals containing iron, chlorine and sulphur while the other one was not sprayed and served as control. Radiometric laboratory tests were carried out on the new films and on samples taken at the end of the trials. The experimental tests showed that both the natural weathering together with the agrochemicals did not modify significantly the radiometric properties of the films in the solar and in the photosynthetically active radiation wavelength range. Within six months of experimental field tests the variations in these radiometric characteristics were at most 10%. Significant variations, up to 70% of the initial value, were recorded for the stabilised films in the long-wave infrared radiation wavelength range.

  9. The Effect of Crop Rotation on Soil Nematode Community Composition in a Greenhouse

    Institute of Scientific and Technical Information of China (English)

    Jingwen LU; Wei SHENG; Qian YU; Zijing CHEN; Qiang XU; Qian WANG; Linlin DONG

    2015-01-01

    Objective] The aim was to identify changes in a nematode community in response to crop rotation and to determine the appropriate catch crop for a green-house. [Method] The experiment was carried out in a typical 6-year-old greenhouse, in which cucumber crops were cultivated twice each year (in spring and autumn), and catch crops were planted in summer. The total number of nematodes was counted and nematode community indices were calculated after col ecting soil sam-ples in different stages. [Result] Total nematode abundance was decreased in the soils of catch crop in contrast with former crops (cucumber crops). The abundance of the nematode community was reduced in the treatment of crop rotation compared to the soils of catch crop. ln addition, the number of nematode taxa was significant-ly reduced by the treatment of crown daisy compared to the treatments of fol owing crops. Crop rotation regulated the functional composition of the nematode community by increasing the omnivores-predators functional group and decreasing the relative abundance of root herbivores. [Conclusion] These results indicate that crop rotation affects the nematode community in abundance, diversity and functional composition of the nematode community and crown daisy can be served as the most appropri-ate catch crop in the greenhouse.

  10. The effect of type and ratio of vermicompost on selected growth indices and nutrients content of tomato at greenhouse conditions

    OpenAIRE

    M.H. Rasouli-Sadaghiani; Moradi, N.; R. Hamzenejhad

    2016-01-01

    This study was conducted to investigate the effect of type and ratio of vermicompost on tomato growth, with five different types of vermicompost (platanus leaves, maple leaves, pruning apple trees and grape, waste of herbal extracts and azolla residues) and four ratios of vermicompost to peat and perlite (2:1 v/v) as 0, 1:3, 2:3 and 3:3, at greenhouse conditions. Results showed that type of vermicompost had a significant effect (P≤ 0.05) on plant height, shoot dry weight, root dry weight, ...

  11. 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

  12. Exploring the Effects of Solar Radiation Management on Water Cycling in a Coupled Land-Atmosphere Model

    Science.gov (United States)

    Dagon, K.; Schrag, D. P.

    2015-12-01

    Solar radiation management (SRM) has been proposed as a form of geoengineering to reduce the warming effects of anthropogenic greenhouse gas emissions. Modeling studies have concluded that SRM roughly compensates for global mean temperature changes induced by greenhouse gas forcing, while large-scale hydrologic cycle changes persist. This is driven by both the sensitivity of surface energy fluxes to changes in shortwave versus longwave radiation, and the physiological effect of carbon dioxide on vegetation. We explore the impact of SRM on the hydrologic cycle that may contribute to local and regional temperature and temperature variability. Regional and seasonal changes are examined under simulations using the Community Land Model, version 4, with reductions in solar radiation relative to simulations with present-day and elevated CO2 concentrations. There are significant regional impacts due to vegetation-climate interactions that are not compensated under SRM, including changes in evapotranspiration, soil moisture, and runoff. In the tropics, evapotranspiration decreases due to increased vegetation water use efficiency, increasing soil moisture. In northern mid-latitudes, decreases in evapotranspiration do not always translate to increases in soil moisture due in part to the precipitation response. These results imply that SRM does not compensate for higher greenhouse gas concentrations when one considers land-atmosphere interactions.

  13. Emerging pattern of global change in the upper atmosphere and ionosphere

    Directory of Open Access Journals (Sweden)

    J. Laštovička

    2008-05-01

    Full Text Available In the upper atmosphere, greenhouse gases produce a cooling effect, instead of a warming effect. Increases in greenhouse gas concentrations are expected to induce substantial changes in the mesosphere, thermosphere, and ionosphere, including a thermal contraction of these layers. In this article we construct for the first time a pattern of the observed long-term global change in the upper atmosphere, based on trend studies of various parameters. The picture we obtain is qualitative, and contains several gaps and a few discrepancies, but the overall pattern of observed long-term changes throughout the upper atmosphere is consistent with model predictions of the effect of greenhouse gas increases. Together with the large body of lower atmospheric trend research, our synthesis indicates that anthropogenic emissions of greenhouse gases are affecting the atmosphere at nearly all altitudes between ground and space.

  14. Arctic climate change: Greenhouse warming unleashed

    Science.gov (United States)

    Mauritsen, Thorsten

    2016-04-01

    Human activity alters the atmospheric composition, which leads to global warming. Model simulations suggest that reductions in emission of sulfur dioxide from Europe since the 1970s could have unveiled rapid Arctic greenhouse gas warming.

  15. Ozone pollution effects on the land carbon sink in the future greenhouse world

    Science.gov (United States)

    Unger, N.; Yue, X.

    2015-12-01

    Ozone pollution has huge impacts on the carbon balance in the United States, Europe and China. While terrestrial ecosystems provide an important sink for surface ozone through stomatal uptake, this process damages photosynthesis, reduces plant growth and biomass accumulation, and affects stomatal control over plant transpiration of water vapor. Effective mitigation of climate change by stabilizing atmospheric carbon dioxide concentrations requires improved understanding of ozone effects on the land carbon sink. Future effects of ozone pollution on the land carbon sink are largely unknown. We apply multiple observational datasets in combination with the Yale Interactive Terrestrial Biosphere (YIBs) model to quantify ozone vegetation damage in the present climatic state and for a broad range of possible futures. YIBs includes a mechanistic ozone damage model that affects both photosynthetic rate and stomatal conductance for low or high ozone plant sensitivity. YIBs is embedded in the NASA GISS ModelE2 global chemistry-climate model to allow a uniquely informed integration of plant physiology, atmospheric chemistry, and climate. The YIBs model has been extensively evaluated using land carbon flux measurements from 145 flux tower sites and multiple satellite products. Chronic ozone exposure in the present day reduces GPP by 11-23%, NPP by 8-16%, stomatal conductance by 8-17% and leaf area index by 2-5% in the summer time eastern United States. Similar response magnitudes are found in Europe but almost doubled damage effects occur in hotspots in eastern China. We investigate future ozone vegetation damage within the context of multiple global change drivers (physical climate change, carbon dioxide fertilization, human energy and agricultural emissions, human land use) at 2050 following the IPCC RCP2.6 and RCP8.5 scenarios. In the RCP8.5 world at 2050, growing season average GPP and NPP are reduced by 20-40% in China and 5-20% in the United States due to the global rise

  16. Effect of Store Atmosphere on Consumer Purchase Intention

    OpenAIRE

    Hussain, Riaz; Ali, Mazhar

    2015-01-01

    This paper aimed at identifying the effects of atmosphere on the consumer purchase intention in international retail chain outlets of Karachi, Pakistan. This was the first study, which investigated the collective impact of atmospheric variables at one point in time on purchase intention. This research was causal in nature. A sample of 300 consumers was taken who usually visited these outlets. Data was collected through a well-structured questionnaire and analyzed through regression a...

  17. Inter-ministerial mission on the greenhouse effect; Mission interministerielle sur l'effet de serre

    Energy Technology Data Exchange (ETDEWEB)

    Fleuret, J.L. [Conseil Regional de Rhone-Alpes, 69 - Charbonnieres-les-Bains (France); Nycollin, E. [Conseil General de la Haute-Savoie, 74 - Annecy (France); Sommeria, G. [Meteo France - Centre National de Recherches Meteorologiques, 75 - Paris (France)] [and others

    2000-07-01

    The 29 and 30 june 2000, a conference on the climatic changes and the effects on the mountain environment, joined together many political, sociological and scientific personalities. Everyone revealed its anxiety towards the environmental and economical impacts for the Alps of the greenhouse gases. The speeches are presented in this document. They expose the ecological hazard and directly bound the economical and sociological danger. They constitute a base reflection on the subject and show that all the levels have to be integrated in the future actions: the political and regional level but also the individual level by the mentality change. (A.L.B.)

  18. Effect of carbon dioxide enrichment on health-promoting compounds and organoleptic properties of tomato fruits grown in greenhouse.

    Science.gov (United States)

    Zhang, Zhiming; Liu, Lihong; Zhang, Min; Zhang, Yongsong; Wang, Qiaomei

    2014-06-15

    The objective of the present study was to evaluate the effect of carbon dioxide (CO2) enrichment on the main health-promoting compounds and organoleptic characteristics of tomato (Solanum lycopersicum) fruits grown in greenhouse. The contents of health-promoting compounds, including lycopene, β-carotene, and ascorbic acid, as well as the flavour, indicated by sugars, titrable acidity, and sugar/acid ratio, were markedly increased in CO2 enrichment fruits. Furthermore, CO2 enrichment significantly enhanced other organoleptic characteristics, including colour, firmness, aroma, and sensory attributes in tomato fruits. The results indicated that CO2 enrichment has potential in promoting the nutritional value and organoleptic characteristics of tomatoes.

  19. L'effet de serre par le CO2 et les gaz traces Greenhouse Effect from CO2 and Trace Gases

    Directory of Open Access Journals (Sweden)

    Bertrand A.

    2006-11-01

    , mainly from combustion and deforestation, and have been progressively accumulating in the Earth's atmosphere, could result in a greenhouse effect that could cause the heating up of the Earth by several degrees in the 21st century. The climatic consequences (melting of ice, etc. would be disastrous. Therefore, we examined the leading parameters involved in this phenomenon: nature of the greenhouse effect, carbon cycle, CO2 transfer on a worldwide scale, trace gases, climatic consequences of the greenhouse effect due to CO2 and trace gases. We reached the following conclusions:(a The CO2 and trace-gas concentration in the atmosphere increases exponentially in the absence of any regulations, and this occurs at the same time as human production of the same substances also at an exponential rate. (b No increase has as yet been detected in the Earth's average temperature due to the greenhouse effect. Moreover, since 1940 we have been going through a period of cooling. (c Human activity also produces antagonistic cooling effects (effect of dust in the atmosphere, etc. that are rather poorly understood. (d The study of ancient climates indicates a regular succession of cool and warm periods, which should reassure us about any sudden and irreversible change in the climate. (e However, it is absolutely necessary to improve our fundamental understanding of the main factors governing the Earth's climate (chemistry of the atmosphere, ocean/ atmosphere transfers, etc. and eventually to limit the production of some trace gases (Freon, in particular.

  20. Effect of dietary protein concentration on ammonia and greenhouse gas emitting potential of dairy manure.

    Science.gov (United States)

    Lee, C; Hristov, A N; Dell, C J; Feyereisen, G W; Kaye, J; Beegle, D

    2012-04-01

    Two experiments were conducted to investigate the effect of dietary crude protein concentration on ammonia (NH(3)) and greenhouse gas (GHG; nitrous oxide, methane, and carbon dioxide) emissions from fresh dairy cow manure incubated in a controlled environment (experiment 1) and from manure-amended soil (experiment 2). Manure was prepared from feces and urine collected from lactating Holstein cows fed diets with 16.7% (DM basis; HCP) or 14.8% CP (LCP). High-CP manure had higher N content and proportion of NH(3)- and urea-N in total manure N than LCP manure (DM basis: 4.4 vs. 2.8% and 51.4 vs. 30.5%, respectively). In experiment 1, NH(3) emitting potential (EP) was greater for HCP compared with LCP manure (9.20 vs. 4.88 mg/m(2) per min, respectively). The 122-h cumulative NH(3) emission tended to be decreased 47% (P=0.09) using LCP compared with HCP manure. The EP and cumulative emissions of GHG were not different between HCP and LCP manure. In experiment 2, urine and feces from cows fed LCP or HCP diets were mixed and immediately applied to lysimeters (61×61×61 cm; Hagerstown silt loam; fine, mixed, mesic Typic Hapludalf) at 277 kg of N/ha application rate. The average NH(3) EP (1.53 vs. 1.03 mg/m(2) per min, respectively) and the area under the EP curve were greater for lysimeters amended with HCP than with LCP manure. The largest difference in the NH(3) EP occurred approximately 24 h after manure application (approximately 3.5 times greater for HCP than LCP manure). The 100-h cumulative NH(3) emission was 98% greater for HCP compared with LCP manure (7,415 vs. 3,745 mg/m(2), respectively). The EP of methane was increased and that of carbon dioxide tended to be increased by LCP compared with HCP manure. The cumulative methane emission was not different between treatments, whereas the cumulative carbon dioxide emission was increased with manure from the LCP diet. Nitrous oxide emissions were low in this experiment and did not differ between treatments. In the

  1. Greenhouse effect, energy conservation; Effet de serre, economie d`energie

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    This symposium is composed of 12 communications grouped in three sessions which titles and themes are: influence of the greenhouse gas emission reduction policy on refrigerating and air conditioning engineering; characteristics and performances of refrigerants and working fluids, circuit architectures, two-phase fluids, single-tube systems and district cooling systems; principles and characteristics of thermo-pumps for heating, refrigerating and air conditioning applications, more especially in residential and small commercial buildings (air condensation thermo-pumps, ammonia thermo-pumps, ground source thermo-pumps), quality assurance

  2. Effects of water-saving irrigation on emissions of greenhouse gases and prokaryotic communities in rice paddy soil.

    Science.gov (United States)

    Ahn, Jae-Hyung; Choi, Min-Young; Kim, Byung-Yong; Lee, Jong-Sik; Song, Jaekyeong; Kim, Gun-Yeob; Weon, Hang-Yeon

    2014-08-01

    The effects of water-saving irrigation on emissions of greenhouse gases and soil prokaryotic communities were investigated in an experimental rice field. The water layer was kept at 1-2 cm in the water-saving (WS) irrigation treatment and at 6 cm in the continuous flooding (CF) irrigation treatment. WS irrigation decreased CH(4) emissions by 78 % and increased N(2)O emissions by 533 %, resulting in 78 % reduction of global warming potential compared to the CF irrigation. WS irrigation did not affect the abundance or phylogenetic distribution of bacterial/archaeal 16S rRNA genes and the abundance of bacterial/archaeal 16S rRNAs. The transcript abundance of CH(4) emission-related genes generally followed CH(4) emission patterns, but the difference in abundance between mcrA transcripts and amoA/pmoA transcripts best described the differences in CH(4) emissions between the two irrigation practices. WS irrigation increased the relative abundance of 16S rRNAs and functional gene transcripts associated with Anaeromyxobacter and Methylocystis spp., suggesting that their activities might be important in emissions of the greenhouse gases. The N(2)O emission patterns were not reflected in the abundance of N(2)O emission-related genes and transcripts. We showed that the alternative irrigation practice was effective for mitigating greenhouse gas emissions from rice fields and that it did not affect the overall size and structure of the soil prokaryotic community but did affect the activity of some groups.

  3. Hydrogen Greenhouse Planets Beyond the Habitable Zone

    CERN Document Server

    Pierrehumbert, Raymond

    2011-01-01

    We show that collision-induced absorption allows molecular hydrogen to act as an incondensible greenhouse gas, and that bars or tens of bars of primordial H2-He mixtures can maintain surface temperatures above the freezing point of water well beyond the "classical" habitable zone defined for CO2 greenhouse atmospheres. Using a 1-D radiative-convective model we find that 40 bars of pure H2 on a 3 Earth-mass planet can maintain a surface temperature of 280K out to 1.5AU from an early-type M dwarf star and 10 AU from a G-type star. Neglecting the effects of clouds and of gaseous absorbers besides H2, the flux at the surface would be sufficient for photosynthesis by cyanobacteria (in the G star case) or anoxygenic phototrophs (in the M star case). We argue that primordial atmospheres of one to several hundred bars of H2-He are possible, and use a model of hydrogen escape to show that such atmospheres are likely to persist further than 1.5 AU from M stars, and 2 AU from G stars, assuming these planets have protect...

  4. Atmospheric refractivity effects on mid-infrared ELT adaptive optics

    CERN Document Server

    Kendrew, S; Mathar, R J; Stuik, R; Hippler, S; Brandl, B

    2008-01-01

    We discuss the effect of atmospheric dispersion on the performance of a mid-infrared adaptive optics assisted instrument on an extremely large telescope (ELT). Dispersion and atmospheric chromaticity is generally considered to be negligible in this wavelength regime. It is shown here, however, that with the much-reduced diffraction limit size on an ELT and the need for diffraction-limited performance, refractivity phenomena should be carefully considered in the design and operation of such an instrument. We include an overview of the theory of refractivity, and the influence of infrared resonances caused by the presence of water vapour and other constituents in the atmosphere. `Traditional' atmospheric dispersion is likely to cause a loss of Strehl only at the shortest wavelengths (L-band). A more likely source of error is the difference in wavelengths at which the wavefront is sensed and corrected, leading to pointing offsets between wavefront sensor and science instrument that evolve with time over a long e...

  5. Economic Analysis of the Effects of Climate Change Induced by Greenhouse Gas Emissions on Agricultural Productions and Available Water Resources (Case Study: Down Lands of the Taleghan Dam

    Directory of Open Access Journals (Sweden)

    M.M. Mozaffari

    2016-03-01

    Full Text Available Introduction: Greenhouse gases absorb the radiation reflected from the earth surface which would otherwise be sent back into space. The composition and mixture of these gases make life on earth possible. In recent years, human activity has affected both the composition and mixture of the atmosphere, modifying the climate. When climate changes, crop production is affected. There are many studies that consider the type and amount of production changes for particular crops, places and scenarios. Others attempt to expand knowledge about production changes and their impacts on economy and regional welfare. Climate change affects agriculture through direct and indirect affects i.e. temperature, and precipitation changes in the biological and physical environment. Restriction in water availability is one of the most dramatic consequences of climate change for the agricultural sector. Water availability is expected to be even more limited in the future. Scarcity of water is due to potential evapotranspiration increase. It is related to increase in air and earth surface temperatures. This phenomenon is important in low-precipitation seasons, and is even more severe in dry areas. The number of regions with loss of soil moisture is expected to increase, resulting in direct economic consequences on the production capacity. Considering the above decisions, the main objective of this paper is to integrate climate change into agricultural decision-making by using an Economic Modeling System to identify the impacts of climate change induced by greenhouse gas emissions on agricultural sector productions and available water resources in the down lands of the Taleghan Dam. Materials and Methods: In this study, the effects of greenhouse gases on climate variables of temperature and precipitation under emission scenarios A1B, A2 and B1 were evaluated using time series data from 1981- 2008 and General Circulation Models (GCM. Then Ordinary Least Squares (OLS was used

  6. Effect of forest drainage on the carbon balance and greenhouse impact of Finnish peatlands

    Energy Technology Data Exchange (ETDEWEB)

    Laine, J.; Minkkinen, K.; Laiho, R. [Helsinki Univ. (Finland). Dept. of Forest Ecology

    1996-12-31

    The aim of this project is to produce an estimate of the change in the biomass and peat carbon stores arising from the drainage of peatlands for forestry, and of the change of greenhouse impact of these ecosystems. The study shows that the subsidence of mire surfaces due to drainage has been relatively small, on average about 20 cm. The observed increase in bulk density after drainage is caused by the physical compression of peat and the post-drainage input of organic material in the form of litter production from the above and below ground parts of the tree layer. Oxidative decay of organic matter may have further increased the compaction of peat, especially in fertile sites. When the changes in peat and vegetation carbon stores are summed up, it seems that, within the site types studied, the total impact of drainage to the ecosystem carbon store is close to zero on the nutrient rich sites and clearly positive on the poorer types. Water level drawdown in peatlands after drainage for forestry appears to decrease the greenhouse impact at least for a few hundred years. The estimated changes in all three emission components (CH{sub 4} emissions, CO{sub 2} sink from peatland and CO{sub 2} sequestered in trees) reduce the radiative forcing by approximately similar amounts

  7. Effects of nitrogen loading on greenhouse gas emissions in salt marshes

    Science.gov (United States)

    Tang, J.; Moseman-Valtierra, S.; Kroeger, K. D.; Morkeski, K.; Mora, J.; Chen, X.; Carey, J.

    2014-12-01

    Salt marshes play an important role in global and regional carbon and nitrogen cycling. We tested the hypothesis that anthropogenic nitrogen loading alters greenhouse gas (GHG, including CO2, CH4, and N2O) emissions and carbon sequestration in salt marshes. We measured GHG emissions biweekly for two growing seasons across a nitrogen-loading gradient of four Spartina salt marshes in Waquoit Bay, Massachusetts. In addition, we conducted nitrogen addition experiments in a pristine marsh by adding low and high nitrate to triplicate plots bi-weekly during the summer. The GHG flux measurements were made in situ with a state-of-the-art mobile gas measurement system using the cavity ring down technology that consists of a CO2/CH4 analyzer (Picarro) and an N2O/CO analyzer (Los Gatos). We observed strong seasonal variations in greenhouse gas emissions. The differences in gas emissions across the nitrogen gradient were not significant, but strong pulse emissions of N2O were observed after nitrogen was artificially added to the marsh. Our results will facilitate model development to simulate GHG emissions in coastal wetlands and support methodology development to assess carbon credits in preserving and restoring coastal wetlands.

  8. The Effect of Different Types of Diet on Greenhouse Gas Emissions in Greece

    Directory of Open Access Journals (Sweden)

    Konstadinos Abeliotis

    2016-02-01

    Full Text Available Diet modifications are explored for the mitigation of greenhouse gases emissions worldwide. The current paper aims at estimating the carbon footprint of the diet of the Greek consumers in 2011. Based on food items consumption data, equivalent CO2 emission factors, the total carbon footprint associated with the per capita Greek diet patterns is calculated. Data for this task are retrieved from readily available resources of existent literature. The per capita carbon footprint resulting from the consumption of food items in Greece in 2011 for the reference scenario is calculated to be 1,827.4 kg CO2/y. In addition, alternative diet scenarios are proposed, their carbon footprint is calculated and suggestions are made for possible sustainable dietary changes. The results indicate that transition to a lacto-ovo-vegetarian diet constitutes a very drastic change towards mitigating greenhouse gases. However its acceptance by the public is very questionable. Thus, the second alternative scenario, which anticipates the substitution of beef by mainly pork and chicken, becomes more relevant. These results could serve as a yardstick for policy interventions aiming at reducing GHG emissions via diet modifications in Greece.

  9. Effect of organic matter strength on anammox for modified greenhouse turtle breeding wastewater treatment.

    Science.gov (United States)

    Chen, Chongjun; Huang, Xiaoxiao; Lei, Chenxiao; Zhang, Tian C; Wu, Weixiang

    2013-11-01

    Anaerobic ammonium-N removal from modified greenhouse turtle breeding wastewater with different chemical oxygen demand (COD) strengths (194.0-577.8 mg L(-1)) at relatively fixed C/N ratios (≈ 2) was investigated using a lab-scale up-flow anaerobic sludge blanket (UASB) anammox reactor. During the entire experiment, the total nitrogen (TN) removal efficiency was about 85% or higher, while the average COD removal efficiency was around 56.5 ± 7.9%. Based on the nitrogen and carbon balance, the nitrogen removal contribution was 79.6 ± 4.2% for anammox, 12.7 ± 3.0% for denitrification+denitritation and 7.7 ± 4.9% for other mechanisms. Denaturing gradient gel electrophoresis (DGGE) analyses revealed that Planctomycete, Proteobacteria and Chloroflexi bacteria were coexisted in the reactor. Anammox was always dominant when the reactor was fed with different COD concentrations, which indicated the stability of the anammox process with the coexistence of the denitrification process in treating greenhouse turtle breeding wastewater.

  10. Photoacoustic Experimental System to Confirm Infrared Absorption Due to Greenhouse Gases

    Science.gov (United States)

    Kaneko, Fumitoshi; Monjushiro, Hideaki; Nishiyama, Masayoshi; Kasai, Toshio; Harris, Harold H.

    2010-01-01

    An experimental system for detecting infrared absorption using the photoacoustic (PA) effect is described. It is aimed for use at high-school level to illustrate the difference in infrared (IR) absorption among the gases contained in the atmosphere in connection with the greenhouse effect. The experimental system can be built with readily…

  11. Simulation of atmospheric temperature effects on cosmic ray muon flux

    Energy Technology Data Exchange (ETDEWEB)

    Tognini, Stefano Castro; Gomes, Ricardo Avelino [Instituto de Física, Universidade Federal de Goiás, CP 131, 74001-970, Goiânia, GO (Brazil)

    2015-05-15

    The collision between a cosmic ray and an atmosphere nucleus produces a set of secondary particles, which will decay or interact with other atmosphere elements. This set of events produced a primary particle is known as an extensive air shower (EAS) and is composed by a muonic, a hadronic and an electromagnetic component. The muonic flux, produced mainly by pions and kaons decays, has a dependency with the atmosphere’s effective temperature: an increase in the effective temperature results in a lower density profile, which decreases the probability of pions and kaons to interact with the atmosphere and, consequently, resulting in a major number of meson decays. Such correlation between the muon flux and the atmosphere’s effective temperature was measured by a set of experiments, such as AMANDA, Borexino, MACRO and MINOS. This phenomena can be investigated by simulating the final muon flux produced by two different parameterizations of the isothermal atmospheric model in CORSIKA, where each parameterization is described by a depth function which can be related to the muon flux in the same way that the muon flux is related to the temperature. This research checks the agreement among different high energy hadronic interactions models and the physical expected behavior of the atmosphere temperature effect by analyzing a set of variables, such as the height of the primary interaction and the difference in the muon flux.

  12. Effects of N and P fertilisation on greenhouse gas (GHG) production in floodplain fen peat: A microcosm fertilisation experiment.

    Science.gov (United States)

    Stanley, Kieran; Heppell, Catherine; Belyea, Lisa; Baird, Andrew

    2016-04-01

    Biogeochemical and hydrological cycles are being significantly perturbed by anthropic activities altering atmospheric mole fractions of greenhouse gases (GHG) and increasing global temperatures. With the intensification of the hydrological cycle, lowland areas, such as floodplain fens, may be inundated more frequently. Rivers in agricultural catchments have the potential to pollute floodplain fens with significant amounts of nitrogen (N) and phosphorus (P); however, the effects of short-term (51 mg L-1 NO3-N) and P (1.4 mg L-1 PO43--P) additions may alter GHG (CO2, CH4, and N2O) production in floodplain fens of contrasting nutrient status under anaerobic conditions. A five-level (control, glucose (G), N+G, P+G, and N+P+G), fully-factorial microcosm experiment was designed and undertaken in Spring 2013 with peat from two floodplain fens under conservation management with similar vegetation (from Norfolk, United Kingdom). One site receives a higher nutrient load than the other and has a historical legacy of higher N and P contents within the peat. Results from the experiment showed no significant difference in CO2 production between the control and fertilised treatments from 0 to 96 hours, but a significant difference between treatments (ANCOVA, between factors: treatment and site; covariate: time; F4,419 = 11.844, p < 0.001) and site (F1,149 = 5.721, p = 0.017) from 96 hours to in the end of the experiment due to fermentation. N2O production only occurred in samples fertilised with N (N+G and N+P+G) due to denitrification. Rates of N2O production were significantly greater in samples from the lower-nutrient site in comparison to the nutrient-rich site (t12= 6.539, p < 0.001 and t12= 7.273, p < 0.001 for N+G and N+P+G fertilised samples, respectively). Fertilisation with N and P had different effects on CH4 production. Samples fertilised with P+G had the highest CH4 production (ANCOVA, between factors: treatment and site; covariate: time; F4,120= 15.026, p < 0

  13. [Effects of nitrogen application on soil greenhouse gas fluxes in Eucalyptus plantations with different soil organic carbon content].

    Science.gov (United States)

    Li, Rui-Da; Zhang, Kai; Su, Dan; Lu, Fei; Wan, Wu-Xing; Wang, Xiao-Ke; Zheng, Hua

    2014-10-01

    The effects of nitrogen fertilization or nitrogen deposition on soil greenhouse gases fluxes has been well studied, while little has been piloted about the effects of nitrogen application on soil greenhouse gas fluxes and its discrepancy with different soil organic carbon content. In our study, we conducted field control experiment in a young Eucalyptus plantation in Southeast China. We compared the effects of 4 levels of nitrogen fertilization (Control: 0 kg · hm(-2); Low N: 84.2 kg · hm(-2); Medium N: 166.8 kg · hm(-2); High N: 333.7 kg · hm(-2)) on soil GHGs fluxes from 2 sites (LC and HC) with significantly different soil organic carbon (SOC) content (P Fertilization had significant priming effect on CO2 and N2O emission fluxes. One month after fertilization, both CO2 and N2O had the flux peak and decreased gradually, and the difference among the treatments disappeared at the end of the growing season. However, fertilization had no significant effect on CH4 oxidation between the 2 sites. (2) Fertilization and SOC were two crucial factors that had significant effects on CO2 and N2O emission. Fertilization had a significant positive effect on CO2 and N2O emission fluxes (P 0.05). The CO2 and N2O emission fluxes were significantly higher in HC than those in LC (P Fertilization and SOC had great interactive effect on CO2 and N2O emission (P fertilization on soil GHGs fluxes were not only in connection with the intensify of nitrogen, but also closely tied to the SOC content. When we assess the effects of nitrogen on soil GHGs fluxes, the difference induced by SOC should not be ignored.

  14. The effect of feeder location on pollen collection by bumble bees in a tomato greenhouse in Ontario, Canada.

    Science.gov (United States)

    Orbán, Levente L; Plowright, C M S; Plowright, R C

    2012-02-01

    The foraging behavior of bumble bees (Bombus impatiens Cresson) was examined as a function of feeder location containing sugar solution in a commercial tomato greenhouse in Manotick, Ontario, Canada. The feeders were located within the nest-box (fed-close) or placed 1.5 m away (fed-far) and the placement of the two types of colonies was counterbalanced over time. No effect of feeder location was found in colony activity levels or in pollen load size. A foraging trade-off between sugar solution and pollen collection, however, was found: the proportion of foraging trips in which pollen was brought back was significantly reduced for fed-far colonies, which contrasts with our laboratory study in which the opposite effect was found. We interpret our findings as possibly reflecting a limitation in pollen supply in the greenhouse: an already possibly strained ability to find and bring back pollen to the colony was accentuated by increasing the task demands of collecting sugar solution.

  15. Note: Measurement system for the radiative forcing of greenhouse gases in a laboratory scale

    Energy Technology Data Exchange (ETDEWEB)

    Kawamura, Yoshiyuki [Department of Intelligent Mechanical Engineering, Fukuoka Institute of Technology, 3-30-1 Wajirohigashi, Higashiku, Fukuoka 811-0295 (Japan)

    2016-01-15

    The radiative forcing of the greenhouse gases has been studied being based on computational simulations or the observation of the real atmosphere meteorologically. In order to know the greenhouse effect more deeply and to study it from various viewpoints, the study on it in a laboratory scale is important. We have developed a direct measurement system for the infrared back radiation from the carbon dioxide (CO{sub 2}) gas. The system configuration is similar with that of the practical earth-atmosphere-space system. Using this system, the back radiation from the CO{sub 2} gas was directly measured in a laboratory scale, which roughly coincides with meteorologically predicted value.

  16. Note: Measurement system for the radiative forcing of greenhouse gases in a laboratory scale.

    Science.gov (United States)

    Kawamura, Yoshiyuki

    2016-01-01

    The radiative forcing of the greenhouse gases has been studied being based on computational simulations or the observation of the real atmosphere meteorologically. In order to know the greenhouse effect more deeply and to study it from various viewpoints, the study on it in a laboratory scale is important. We have developed a direct measurement system for the infrared back radiation from the carbon dioxide (CO2) gas. The system configuration is similar with that of the practical earth-atmosphere-space system. Using this system, the back radiation from the CO2 gas was directly measured in a laboratory scale, which roughly coincides with meteorologically predicted value.

  17. Probing possible decoherence effects in atmospheric neutrino oscillations.

    Science.gov (United States)

    Lisi, E; Marrone, A; Montanino, D

    2000-08-01

    It is shown that the results of the Super-Kamiokande atmospheric neutrino experiment, interpreted in terms of nu(mu)nu(tau) flavor transitions, can probe possible decoherence effects induced by new physics (e.g., by quantum gravity) with high sensitivity, supplementing current laboratory tests based on kaon oscillations and on neutron interferometry. By varying the (unknown) energy dependence of such effects, one can either obtain strong limits on their amplitude or use them to find an unconventional solution to the atmospheric nu anomaly based solely on decoherence.

  18. Greenhouse gases and recovery of the Earth's ozone layer

    Science.gov (United States)

    Dyominov, I. G.; Zadorozhny, A. M.

    A numerical two-dimension zonally average interactive dynamical radiative-photochemical model of the atmosphere is used for investigation the role of the greenhouse gases CO2, CH4, and N2O in the recovery of the Earth's ozone layer after reduction of anthropogenic discharges in the atmosphere of chlorine and bromine compounds. The model allows calculating self-consistently diabatic circulation, temperature, gaseous composition of the troposphere and stratosphere at latitudes from the South to North Poles, as well as distribution of sulphate aerosol particles and polar stratospheric clouds of types I and II. The scenarios of future changes of the greenhouse gases and chlorine and bromine species are taken from Climate Change 1995. The calculations show that expected cooling of the stratosphere caused by the increasing of the greenhouse gases, particularly CO2, enhances the ozone concentration in the stratosphere due to a weakness of the efficiencies of all catalytic cycles of the ozone destruction caused by temperature dependencies of photochemical reactions. The result of this effect is a significant acceleration of the ozone layer recovery after reduction of anthropogenic discharges in the atmosphere of chlorine and bromine species. On the other hand, the cooling of the stratosphere intensifies a formation of the polar stratospheric clouds in the lower stratosphere in the Polar Regions. Heterogeneous reactions on the polar stratospheric clouds, which are the key processes in the destruction of the ozone layer at the high latitudes, lead to more intensive ozone depletion here, which causes a delay of the ozone layer recovery. The calculations show that this effect is weaker than the first one so that the global ozone will recover faster under conditions of continuing anthropogenic growth of the greenhouse gases. The model predicts in this case that the annual average global ozone will reach its undisturbed level of 1980 by about 2040. If the growth of the

  19. Magnetospheric effects in atmospheric electricity at high latitudes

    Science.gov (United States)

    Shumilov, O. I.; Kasatkina, E. A.; Frank-Kamenetsky, A. V.; Raspopov, O. M.; Vasiljev, A. N.; Struev, A. G.

    2003-04-01

    Measurements of the vertical atmospheric electric field (Ez) made at auroral station Apatity (geomagnetic latitude: 63.8) and polar cap station Vostok, Antarctica (geomagnetic latitude: -89.3) in 2001-2002 have been analyzed. The measurements were made by a high-latitude computer-aided complex installed at Apatity in 2001. It consists of three spatially placed microbarographs for measurements of atmospheric waves, a device for air conductivity measurement and a device for measurement of vertical component of the atmospheric electric field. The computer-aided system permits to get information with a frequency of five times per second. The ground level atmospheric electric field was found to have systematic local diurnal and seasonal variations. Diurnal variations of atmospheric potential gradient were found to have a departure from the Carnegie curve. A distinct difference in the diurnal variation of atmospheric electric field has been observed also between disturbed (Kp>30) and extremely quiet (Kplatitude electric field variations appear to be the result of solar wind-magnetosphere-ionosphere coupling. Besides, we have found the similarity between the diurnal course of the atmospheric electric field under the quiet geomagnetic conditions and the diurnal variation of galactic cosmic rays. These results have been explained in terms of calculated effective Bz component of the interpalnetary magnetic field arising due to variation of the geomagnetic dipole axis inclination during the Earth's rotation. The results of analysis of the influence of extreme weather conditions (rain, snow, snowstorm, stormclouds, thunderstorms, lightning) on atmospheric electricity (electric field and conductivity) are also discussed. This work was supported by EC (grant INTAS 97-31008) and RFBR (grant 01-05-64850).

  20. Effects of washing, peeling, storage, and fermentation on residue contents of carbaryl and mancozeb in cucumbers grown in greenhouses.

    Science.gov (United States)

    Saeedi Saravi, S S; Shokrzadeh, M

    2016-06-01

    Cucumbers grown in two different greenhouses were exposed to mancozeb and carbaryl at different times. The effects of 10-day preharvest period, water and detergent washing, peeling, predetermined storage period at 4°C (refrigeration), and fermentation on the reduction of residue levels in the plant tissues were investigated. Mancozeb and carbaryl residues in cucumbers were determined by gas chromatography-electron capture detection. Results showed that residue levels in samples, which were collected after 10 days following the pesticide application, were significantly lower than the samples collected after 2 h subsequent to the pesticide application. The culinary applications were effective in reducing the residue levels of the pesticides in cucumbers. As a result, non-fermentative pickling in sodium chloride and acetic acid was the most effective way to reduce the mancozeb and carbaryl residues of the cucumbers.

  1. Synthetic Spectra and Colors of Young Giant Planet Atmospheres: Effects of Initial Conditions and Atmospheric Metallicity

    CERN Document Server

    Fortney, Jonathan J; Saumon, Didier; Lodders, Katharina

    2008-01-01

    We examine the spectra and infrared colors of the cool methane-dominated atmospheres at Teff < 1400 K expected for young gas giant planets. We couple these spectral calculations to an updated version of the Marley et al. (2007) giant planet thermal evolution models that include formation by core accretion-gas capture. These relatively cool "young Jupiters" can be 1-6 magnitudes fainter than predicted by standard cooling tracks that include a traditional initial condition, which may provide a diagnostic of formation. If correct, this would make true Jupiter-like planets much more difficult to detect at young ages than previously thought. Since Jupiter and Saturn are of distinctly super-solar composition, we examine emitted spectra for model planets at both solar metallicity and a metallicity of 5 times solar. These metal-enhanced young Jupiters have lower pressure photospheres than field brown dwarfs of the same effective temperatures arising from both lower surface gravities and enhanced atmospheric opacit...

  2. Short-term climatic fluctuations and the interpretation of recent observations in terms of greenhouse effect; Les fluctuations a court terme du climat et l'interpretation des observations recentes en terme d'effet de serre

    Energy Technology Data Exchange (ETDEWEB)

    Andre, J.C. [Centre Europeen de Recherche et de Formation Avancee en Calcul Scientifique, 31 - Toulouse (France); Royer, J.F. [Centre National de Recherches Meteorologiques, Meteo-France, 31 - Toulouse (France)

    1999-02-01

    Simulations of future climate made with coupled general circulation models of the atmosphere and ocean predict that the increase of the concentration of greenhouse gases released in the atmosphere by man's activities will have a large influence on the climate of the next century. The identification of the climatic impact produced by the rapid increase in carbon dioxide concentration in the last decades is made difficult by strong inter-annual climate variability, and requires the application of statistical techniques combining several climatic indicators (method of climatic 'fingerprints') so as to improve the detection of a possible anthropogenic perturbation. In this paper we review the evolution through the last decades of several climate indicators showing global warming, its geographical distribution, sea level, the hydrological cycle and the response of vegetation, and we compare them to the model results predicted in climate scenarios. The coherence between model results and observed climatic trends shows that the additional greenhouse effect is starting to become detectable in recent climatic data. (authors)

  3. Effect of different levels of nitrogen on rhizosphere bacterial community structure in intensive monoculture of greenhouse lettuce

    Science.gov (United States)

    Li, Jian-Gang; Shen, Min-Chong; Hou, Jin-Feng; Li, Ling; Wu, Jun-Xia; Dong, Yuan-Hua

    2016-01-01

    Pyrosequencing-based analyses revealed significant effects among low (N50), medium (N80), and high (N100) fertilization on community composition involving a long-term monoculture of lettuce in a greenhouse in both summer and winter. The non-fertilized control (CK) treatment was characterized by a higher relative abundance of Actinobacteria, Acidobacteria, and Chloroflexi; however, the average abundance of Firmicutes typically increased in summer, and the relative abundance of Bacteroidetes increased in winter in the N-fertilized treatments. Principle component analysis showed that the distribution of the microbial community was separated by a N gradient with N80 and N100 in the same group in the summer samples, while CK and N50 were in the same group in the winter samples, with the other N-level treatments existing independently. Redundancy analysis revealed that available N, NO3−-N, and NH4+-N, were the main environmental factors affecting the distribution of the bacterial community. Correlation analysis showed that nitrogen affected the shifts of microbial communities by strongly driving the shifts of Firmicutes, Bacteroidetes, and Proteobacteria in summer samples, and Bacteroidetes, Actinobacteria, and Acidobacteria in winter samples. The study demonstrates a novel example of rhizosphere bacterial diversity and the main factors influencing rizosphere microbial community in continuous vegetable cropping within an intensive greenhouse ecosystem. PMID:27121918

  4. Effect of different levels of nitrogen on rhizosphere bacterial community structure in intensive monoculture of greenhouse lettuce

    Science.gov (United States)

    Li, Jian-Gang; Shen, Min-Chong; Hou, Jin-Feng; Li, Ling; Wu, Jun-Xia; Dong, Yuan-Hua

    2016-04-01

    Pyrosequencing-based analyses revealed significant effects among low (N50), medium (N80), and high (N100) fertilization on community composition involving a long-term monoculture of lettuce in a greenhouse in both summer and winter. The non-fertilized control (CK) treatment was characterized by a higher relative abundance of Actinobacteria, Acidobacteria, and Chloroflexi; however, the average abundance of Firmicutes typically increased in summer, and the relative abundance of Bacteroidetes increased in winter in the N-fertilized treatments. Principle component analysis showed that the distribution of the microbial community was separated by a N gradient with N80 and N100 in the same group in the summer samples, while CK and N50 were in the same group in the winter samples, with the other N-level treatments existing independently. Redundancy analysis revealed that available N, NO3--N, and NH4+-N, were the main environmental factors affecting the distribution of the bacterial community. Correlation analysis showed that nitrogen affected the shifts of microbial communities by strongly driving the shifts of Firmicutes, Bacteroidetes, and Proteobacteria in summer samples, and Bacteroidetes, Actinobacteria, and Acidobacteria in winter samples. The study demonstrates a novel example of rhizosphere bacterial diversity and the main factors influencing rizosphere microbial community in continuous vegetable cropping within an intensive greenhouse ecosystem.

  5. Effect of different levels of nitrogen on rhizosphere bacterial community structure in intensive monoculture of greenhouse lettuce.

    Science.gov (United States)

    Li, Jian-Gang; Shen, Min-Chong; Hou, Jin-Feng; Li, Ling; Wu, Jun-Xia; Dong, Yuan-Hua

    2016-04-28

    Pyrosequencing-based analyses revealed significant effects among low (N50), medium (N80), and high (N100) fertilization on community composition involving a long-term monoculture of lettuce in a greenhouse in both summer and winter. The non-fertilized control (CK) treatment was characterized by a higher relative abundance of Actinobacteria, Acidobacteria, and Chloroflexi; however, the average abundance of Firmicutes typically increased in summer, and the relative abundance of Bacteroidetes increased in winter in the N-fertilized treatments. Principle component analysis showed that the distribution of the microbial community was separated by a N gradient with N80 and N100 in the same group in the summer samples, while CK and N50 were in the same group in the winter samples, with the other N-level treatments existing independently. Redundancy analysis revealed that available N, NO3(-)-N, and NH4(+)-N, were the main environmental factors affecting the distribution of the bacterial community. Correlation analysis showed that nitrogen affected the shifts of microbial communities by strongly driving the shifts of Firmicutes, Bacteroidetes, and Proteobacteria in summer samples, and Bacteroidetes, Actinobacteria, and Acidobacteria in winter samples. The study demonstrates a novel example of rhizosphere bacterial diversity and the main factors influencing rizosphere microbial community in continuous vegetable cropping within an intensive greenhouse ecosystem.

  6. Optimal use of biofuels to reduce the contribution to the greenhouse effect; Optimal anvaendning av biobraensle foer minskning av vaexthuseffekten

    Energy Technology Data Exchange (ETDEWEB)

    Aasblad, A.; Franck, P.Aa.; Berntsson, T. [Chalmers Industriteknik, Goeteborg (Sweden). CIT Energiteknisk Analys

    1995-12-31

    This report analyses whether the use of biofuels in district heating systems is a cost effective measure to decrease the emissions of greenhouse gases in Sweden or not. We have taken the year 2005 as an average for the next 15 to 20 years and used prognosis from NUTEK to estimate the national electricity production system together with fuel and electricity prices. Three sizes of district heating systems have been considered with annual heat loads of 2, 60 and 300 GWh. We have identified the optimal mix of production techniques that produces heat to the lowest total cost for a given allowed level of greenhouse gas emissions. Conclusions about the individual technologies can be drawn by studying the change in the cost optimal production mix when the allowed level of emission changes. To get substantially lower carbon dioxide emissions, CHP-plants based on biofuels must be introduced. In Sweden, however, the carbon dioxide emissions associated with electricity production are low (even in the year 2005) and the prognosis for the electricity price does not make it profitable to introduce CHP-plants on economical grounds. This means that the cost for decreasing emission substantially below 50 kg/MWh with CHP-plants normally is expensive since the decrease in emissions is low and the increase in cost is high. 17 refs, 34 figs, 21 tabs

  7. Impact of greenhouse gases on the Earth's ozone layer

    Science.gov (United States)

    Zadorozhny, Alexander

    A numerical 2-D zonally averaged interactive dynamical radiative-photochemical model of the ozonosphere including aerosol physics is used to examine the role of the greenhouse gases CO2 , CH4 , and N2 O in the future long-term changes of the Earth's ozone layer, in particular in its recovery after reduction of anthropogenic discharges of chlorine and bromine compounds into the atmosphere. The model allows calculating self-consistently diabatic circulation, temperature, gaseous composition of the troposphere and stratosphere at latitudes from the South to North Poles, as well as distribution of sulphate aerosol particles and polar stratospheric clouds (PSCs) of types I and II. The scenarios of expected changes of the anthropogenic pollutants for the period from 1980 through 2050 are taken from Climate Change 2001. The processes, which determine the influence of anthropogenic growth of atmospheric abundance of the greenhouse gases on the dynamics of recovery of the Earth's ozone layer, have been studied in details. Expected cooling of the stratosphere caused by increases of greenhouse gases, most importantly CO2 , essentially influences the ozone layer by two ways: through temperature dependencies of the gas phase reaction rates and through enhancement of polar ozone depletion via increased PSC formation. The model calculations show that a weakness in efficiencies of all gas phase catalytic cycles of the ozone destruction due to cooling of the stratosphere is a dominant mechanism of the impact of the greenhouse gases on the ozone layer in Antarctic as well as at the lower latitudes. This mechanism leads to a significant acceleration of the ozone layer recovery here because of the greenhouse gases growth. On the contrary, the mechanism of the impact of the greenhouse gases on the ozone through PSC modification begins to be more effective in Arctic in comparison with the gas phase mechanism in springs after about 2020, which leads to retard the expected recovery of the

  8. Effects of light propagation in middle intensity atmospheric turbulence

    Institute of Scientific and Technical Information of China (English)

    Xiubua YUAN; Dexiu HUANG; Bangxu LI

    2009-01-01

    The purpose of this report is to present an experimental study of the effects of light propagation through atmospheric turbulence.Free space optical communication is a line-of-sight technology that transmits a modulated beam of visible light through the atmosphere for broadband communication.The fundamental limitations of free space optical communications arise from the environment through which it propagates.However these systems are vulnerable to atmospheric turbulence, such as attenuation and scintillation, Scintillation is due to the air index variation under the temperature effects.These factors cause an attenuated receiver signal and lead to higher bit error rate (BER).An experiment of laser propagation was carried out to characterize the light intensity through turbulent air in the laboratory environment.The experimental results agree with the calculation based on Rytov for the case of weak to intermediate turbulence.Also, we show the characteristics of irradiance scintillation, intensity distribution and atmospheric turbulence strength.By means of laboratory simulated turbulence, the turbulence box is constructed with the following measurements: 0.5 m wide, 2m long and 0.5m high.The simulation box consists of three electric heaters and is well described for understanding the experimental set up.The fans and heaters are used to increase the homogeneity of turbulence and to create different scintillation indices.The received intensity scintillation and atmosphere turbulence strength were obtained and the variation of refractive index, with its corresponding structure parameter, is calculated from the experimental results.

  9. A Three-Tier Diagnostic Test to Assess Pre-Service Teachers' Misconceptions about Global Warming, Greenhouse Effect, Ozone Layer Depletion, and Acid Rain

    Science.gov (United States)

    Ozge Arslan, Harika; Cigdemoglu, Ceyhan; Moseley, Christine

    2012-07-01

    This study describes the development and validation of a three-tier multiple-choice diagnostic test, the atmosphere-related environmental problems diagnostic test (AREPDiT), to reveal common misconceptions of global warming (GW), greenhouse effect (GE), ozone layer depletion (OLD), and acid rain (AR). The development of a two-tier diagnostic test procedure as described by Treagust constitutes the framework for this study. To differentiate a lack of knowledge from a misconception, a certainty response index is added as a third tier to each item. Based on propositional knowledge statements, related literature, and the identified misconceptions gathered initially from 157 pre-service teachers, the AREPDiT was constructed and administered to 256 pre-service teachers. The Cronbach alpha reliability coefficient of the pre-service teachers' scores was estimated to be 0.74. Content and face validations were established by senior experts. A moderate positive correlation between the participants' both-tiers scores and their certainty scores indicated evidence for construct validity. Therefore, the AREPDiT is a reliable and valid instrument not only to identify pre-service teachers' misconceptions about GW, GE, OLD, and AR but also to differentiate these misconceptions from lack of knowledge. The results also reveal that a majority of the respondents demonstrated limited understandings about atmosphere-related environmental problems and held six common misconceptions. Future studies could test the AREPDiT as a tool for assessing the misconceptions held by pre-service teachers from different programs as well as in-service teachers and high school students.

  10. Increased insolation threshold for runaway greenhouse processes on Earth like planets

    CERN Document Server

    Leconte, Jérémy; Charnay, Benjamin; Wordsworth, Robin; Pottier, Alizée

    2013-01-01

    Because the solar luminosity increases over geological timescales, Earth climate is expected to warm, increasing water evaporation which, in turn, enhances the atmospheric greenhouse effect. Above a certain critical insolation, this destabilizing greenhouse feedback can "runaway" until all the oceans are evaporated. Through increases in stratospheric humidity, warming may also cause oceans to escape to space before the runaway greenhouse occurs. The critical insolation thresholds for these processes, however, remain uncertain because they have so far been evaluated with unidimensional models that cannot account for the dynamical and cloud feedback effects that are key stabilizing features of Earth's climate. Here we use a 3D global climate model to show that the threshold for the runaway greenhouse is about 375 W/m$^2$, significantly higher than previously thought. Our model is specifically developed to quantify the climate response of Earth-like planets to increased insolation in hot and extremely moist atmo...

  11. The effect of land-use change on the net exchange rates of greenhouse gases: a meta-analytical approach

    Directory of Open Access Journals (Sweden)

    D.-G. Kim

    2014-01-01

    Full Text Available One of the environmental impacts of land-use change (LUC is a change in the net exchange of the greenhouse gases (GHGs carbon dioxide (CO2, methane (CH4 and nitrous oxide (N2O. Here we summarize findings based on a new global database containing data sets of changes in soil organic carbon stocks and soil CH4 and N2O fluxes. We combine that with estimates of biomass carbon stock changes and enteric CH4 emissions following LUC. Data were expressed in common units by converting net CH4 and N2O fluxes to CO2 equivalents (CO2 eq using established global warming potentials, and carbon-stock changes were converted to annual net fluxes by averaging stock changes over 100 yr. Conversion from natural forest to cropland resulted in the greatest increase in net GHG fluxes, while conversion of cropland to secondary forest resulted in the greatest reduction in net GHG emissions. Specifically, LUC from natural forest to crop and grasslands led to net fluxes of 6.2 ± 1.6 (Mean ± 95% confidence intervals and 4.8 ± 1.6 t CO2 eq ha−1 yr−1 to the atmosphere, respectively. Conversely, conversion from crop and grasslands to secondary forest reduced net emissions by 6.1 ± 4.1 and 3.9 ± 1.2 t CO2 eq ha−1 yr−1, respectively. Land-use change impacts were generally dominated by changes in biomass carbon. A retrospective analysis indicated that LUC from natural forests to agricultural lands contributed a cumulative 1326 ± 449 Gt CO2 eq between 1765 and 2005, which is equivalent to average emissions of 5.5 ± 1.6 Gt CO2 eq yr−1. This study demonstrates how specific LUCs can positively or negatively affect net GHG fluxes to the atmosphere.

  12. Cooling the greenhouse effect: Options and costs for reducing CO{sub 2} emissions from the American Electric Power Company

    Energy Technology Data Exchange (ETDEWEB)

    Helme, N.; Popovich, M.G.; Gille, J. [Center for Clean Air Policy, Washington, DC (United States)

    1993-05-01

    A recent report from the National Academy of Sciences concludes that the earth is likely to face a doubling of preindustrial greenhouse gases in the next half century. This doubling could be expected to push average global temperatures. up from between 1.8 to 9 degrees Fahrenheit. Much of the potential for human impacts on the global climate is linked to fossil fuel consumption. Carbon dioxide emissions from energy consumption in the US totals about one-quarter of the world`s total emissions from energy consumption. Global warming is different from other environmental problems because CO{sub 2} emissions can be captured naturally by trees, grasses, soil, and other plants. In contrast, acid rain emissions reductions can only be accomplished through switching to lower-polluting fuels, conserving energy, or installing costly retrofit technologies. Terrestrial biota, such as trees, plants, grasses and soils, directly affect the CO{sub 2} concentrations in the atmosphere. A number of reports have concluded that forestry and land-use practices can increase CO{sub 2} sequestration and can help reduce or delay the threat of global warming.

  13. Effects of Irrigation in India on the Atmospheric Water Budget

    NARCIS (Netherlands)

    Tuinenburg, O.A.; Hutjes, R.W.A.; Stacke, T.; Wiltshire, A.; Lucas-Picher, P.

    2014-01-01

    The effect of large-scale irrigation in India on the moisture budget of the atmosphere was investigated using three regional climate models and one global climate model, all of which performed an irrigated run and a natural run without irrigation. Using a common irrigation map, year-round irrigation

  14. The effects on the atmosphere of a major nuclear exchange

    Energy Technology Data Exchange (ETDEWEB)

    1985-01-01

    Most of the earth's population would survive the immediate horrors of a nuclear holocaust, but what long-term climatological changes would affect their ability to secure food and shelter. This sobering report considers the effects of fine dust from ground-level detonations, of smoke from widespread fires, and of chemicals released into the atmosphere. The authors use mathematical models of atmospheric processes and data from natural situations - e.g., volcanic eruptions and arctic haze - to draw their conclusions.

  15. The effect of atmospheric corona treatment on AA1050 aluminium

    DEFF Research Database (Denmark)

    Jariyaboon, Manthana; Møller, Per; Dunin-Borkowski, Rafal E.

    2010-01-01

    The effect of atmospheric corona discharge on AM 050 aluminium surface was investigated using electrochemical polarization, SEM-EDX, FIB-SEM. and XPS. The corona treatment was performed with varying time (1, 5, and 15 min) in atmospheric air. A 200 nm oxide layer was generated on AA1050 after...... the 15 min air corona treatment. A significant reduction in anodic and cathodic reactivities was observed starting from 1 min exposure, which further decreased with prolonged exposure (15 min) and after delayed testing (after 30 days). The reduction in surface reactivity is due to the formation...

  16. 设施花卉高效栽培技术探讨及效益分析%The Effective Cultivation Technology and Effectiveness Analysis of Greenhouse Flowers

    Institute of Scientific and Technical Information of China (English)

    罗拥兵

    2015-01-01

    通过设施花卉栽培项目试验,筛选了适于市场销售的优良花卉品种,并对其经济效益进行了分析。%Through the greenhouse flower cultivation trial, this study screened excellent varieties of flowers that were suitable for the market, and analyzed their economic effectiveness.

  17. Soil management options to sequester carbon and mitigate the greenhouse effect

    NARCIS (Netherlands)

    Batjes, N.H.

    2000-01-01

    The imbalance between global sources and sinks in the global budget of atmospheric CO2 is one of the most important problems in the study of global change. At present there is a 'missing sink' of about 1-2 Pg C yr -1. It is likely that a major part of this sink for carbon is to be found in the funct

  18. Effects of land use intensity on the full greenhouse gas balance in an Atlantic peat bog

    Science.gov (United States)

    Beetz, S.; Liebersbach, H.; Glatzel, S.; Jurasinski, G.; Buczko, U.; Höper, H.

    2013-02-01

    Wetlands can either be net sinks or net sources of greenhouse gases (GHGs), depending on the mean annual water level and other factors like average annual temperature, vegetation development, and land use. Whereas drained and agriculturally used peatlands tend to be carbon dioxide (CO2) and nitrous oxide (N2O) sources but methane (CH4) sinks, restored (i.e. rewetted) peatlands rather incorporate CO2, tend to be N2O neutral and release CH4. One of the aims of peatland restoration is to decrease their global warming potential (GWP) by reducing GHG emissions. We estimated the greenhouse gas exchange of a peat bog restoration sequence over a period of 2 yr (1 July 2007-30 June 2009) in an Atlantic raised bog in northwest Germany. We set up three study sites representing different land use intensities: intensive grassland (deeply drained, mineral fertilizer, cattle manure and 4-5 cuts per year); extensive grassland (rewetted, no fertilizer or manure, up to 1 cutting per year); near-natural peat bog (almost no anthropogenic influence). Daily and annual greenhouse gas exchange was estimated based on closed-chamber measurements. CH4 and N2O fluxes were recorded bi-weekly, and net ecosystem exchange (NEE) measurements were carried out every 3-4 weeks. Annual sums of CH4 and N2O fluxes were estimated by linear interpolation while NEE was modelled. Regarding GWP, the intensive grassland site emitted 564 ± 255 g CO2-C equivalents m-2 yr-1 and 850 ± 238 g CO2-C equivalents m-2 yr-1 in the first (2007/2008) and the second (2008/2009) measuring year, respectively. The GWP of the extensive grassland amounted to -129 ± 231 g CO2-C equivalents m-2 yr-1 and 94 ± 200 g CO2-C equivalents m-2 yr-1, while it added up to 45 ± 117 g CO2-C equivalents m-2 yr-1 and -101 ± 93 g CO2-C equivalents m-2 yr-1 in 2007/08 and 2008/09 for the near-natural site. In contrast, in calendar year 2008 GWP aggregated to 441 ± 201 g CO2-C equivalents m-2 yr-1, 14 ± 162 g CO2-C equivalents m-2 yr-1

  19. Effects of land use intensity on the full greenhouse gas balance in an Atlantic peat bog

    Directory of Open Access Journals (Sweden)

    S. Beetz

    2013-02-01

    Full Text Available Wetlands can either be net sinks or net sources of greenhouse gases (GHGs, depending on the mean annual water level and other factors like average annual temperature, vegetation development, and land use. Whereas drained and agriculturally used peatlands tend to be carbon dioxide (CO2 and nitrous oxide (N2O sources but methane (CH4 sinks, restored (i.e. rewetted peatlands rather incorporate CO2, tend to be N2O neutral and release CH4. One of the aims of peatland restoration is to decrease their global warming potential (GWP by reducing GHG emissions.

    We estimated the greenhouse gas exchange of a peat bog restoration sequence over a period of 2 yr (1 July 2007–30 June 2009 in an Atlantic raised bog in northwest Germany. We set up three study sites representing different land use intensities: intensive grassland (deeply drained, mineral fertilizer, cattle manure and 4–5 cuts per year; extensive grassland (rewetted, no fertilizer or manure, up to 1 cutting per year; near-natural peat bog (almost no anthropogenic influence. Daily and annual greenhouse gas exchange was estimated based on closed-chamber measurements. CH4 and N2O fluxes were recorded bi-weekly, and net ecosystem exchange (NEE measurements were carried out every 3–4 weeks. Annual sums of CH4 and N2O fluxes were estimated by linear interpolation while NEE was modelled.

    Regarding GWP, the intensive grassland site emitted 564 ± 255 g CO2–C equivalents m−2 yr−1 and 850 ± 238 g CO2–C equivalents m−2 yr−1 in the first (2007/2008 and the second (2008/2009 measuring year, respectively. The GWP of the extensive grassland amounted to −129 ± 231 g CO2–C equivalents m−2 yr−1 and 94 ± 200 g CO2–C equivalents m−2 yr

  20. Water cycles in closed ecological systems: effects of atmospheric pressure

    Science.gov (United States)

    Rygalov, Vadim Y.; Fowler, Philip A.; Metz, Joannah M.; Wheeler, Raymond M.; Bucklin, Ray A.; Sager, J. C. (Principal Investigator)

    2002-01-01

    In bioregenerative life support systems that use plants to generate food and oxygen, the largest mass flux between the plants and their surrounding environment will be water. This water cycle is a consequence of the continuous change of state (evaporation-condensation) from liquid to gas through the process of transpiration and the need to transfer heat (cool) and dehumidify the plant growth chamber. Evapotranspiration rates for full plant canopies can range from 1 to 10 L m-2 d-1 (1 to 10 mm m-2 d-1), with the rates depending primarily on the vapor pressure deficit (VPD) between the leaves and the air inside the plant growth chamber. VPD in turn is dependent on the air temperature, leaf temperature, and current value of relative humidity (RH). Concepts for developing closed plant growth systems, such as greenhouses for Mars, have been discussed for many years and the feasibility of such systems will depend on the overall system costs and reliability. One approach for reducing system costs would be to reduce the operating pressure within the greenhouse to reduce structural mass and gas leakage. But managing plant growth environments at low pressures (e.g., controlling humidity and heat exchange) may be difficult, and the effects of low-pressure environments on plant growth and system water cycling need further study. We present experimental evidence to show that water saturation pressures in air under isothermal conditions are only slightly affected by total pressure, but the overall water flux from evaporating surfaces can increase as pressure decreases. Mathematical models describing these observations are presented, along with discussion of the importance for considering "water cycles" in closed bioregenerative life support systems.

  1. Gardening with Greenhouses

    Science.gov (United States)

    Keeler, Rusty

    2010-01-01

    Greenhouses come in all shapes, sizes, and price ranges: from simple hand-built plastic-covered frames to dazzling geodesic domes. Some child care centers install greenhouses as a part of their outdoor garden space. Other centers have incorporated a greenhouse into the building itself. Greenhouses provide a great opportunity for children to grow…

  2. Technology Opportunities to Reduce U.S. Greenhouse Gas Emissions

    Energy Technology Data Exchange (ETDEWEB)

    National Lab Directors, . .

    2001-04-05

    The rise in greenhouse gas emissions from fossil fuel combustion and industrial and agricultural activities has aroused international concern about the possible impacts of these emissions on climate. Greenhouse gases--mostly carbon dioxide, some methane, nitrous oxide and other trace gases--are emitted to the atmosphere, enhancing an effect in which heat reflected from the earth's surface is kept from escaping into space, as in a greenhouse. Thus, there is concern that the earth's surface temperature may rise enough to cause global climate change. Approximately 90% of U.S. greenhouse gas emissions from anthropogenic sources come from energy production and use, most of which are a byproduct of the combustion of fossil fuels. On a per capita basis, the United States is one of the world's largest sources of greenhouse gas emissions, comprising 4% of the world's population, yet emitting 23% of the world's greenhouse gases. Emissions in the United States are increasing at around 1.2% annually, and the Energy Information Administration forecasts that emissions levels will continue to increase at this rate in the years ahead if we proceed down the business-as-usual path. President Clinton has presented a two-part challenge for the United States: reduce greenhouse gas emissions and grow the economy. Meeting the challenge will mean that in doing tomorrow's work, we must use energy more efficiently and emit less carbon for the energy expended than we do today. To accomplish these goals, President Clinton proposed on June 26, 1997, that the United States ''invest more in the technologies of the future''. In this report to Secretary of Energy Pena, 47 technology pathways are described that have significant potential to reduce carbon dioxide emissions. The present study was completed before the December 1997 United Nations Framework Convention on Climate Change and is intended to provide a basis to evaluate technology

  3. Health Effects of Greenhouses and Pesticide Application on Farmworkers%温室环境及农药使用对作业人员健康的影响

    Institute of Scientific and Technical Information of China (English)

    孙健; 杨惠芳

    2013-01-01

    Greenhouses play a positive role in supplying more vegetables in winter and increasing fanners' income. But the special microenvironment of greenhouses, especially high temperature and high humidity, could make fanners suffering from higher pesticide exposure than those working in open-air and increase health risks to greenhouse farmworkers. The growing researches on greenhouse microenvironment in China mainly focus on improving agricultural production efficiency and economic benefits, but studies on the related health effects are limited. With rapid economic development in China, the occupational health security of greenhouse farmworkers draws more attention. This article summarized domestic and international studies on health effects of pesticide application in greenhouse, in terms of greenhouse microenvironment, pesticide exposure of greenhouse farmworkers, and its health effects, in order to provide recommendations for improving occupational safety and health of greenhouse farmworkers in China.%温室生产,在改善冬季蔬菜供应,增加农民收入等方面有着积极的作用,但由于其特殊的微环境,导致温室作业人员的健康风险增高,温室中的高温、高湿等特殊微环境,使得温室中的作业人员农药暴露更高于露天环境,是造成温室作业人员健康损害的最重要因素之一.我国大陆对温室微环境的研究虽也越来越多,但主要集中在提高农业劳动生产率与经济效益方面,对劳动者的健康影响研究仍有限.随着经济的快速发展,温室作业人员职业卫生安全也越来越引起人们的重视.因此,本研究在总结目前国内外温室农药使用对温室作业人员健康影响的基础上,从温室微环境的特点、温室作业人员农药使用与暴露情况,以及温室中农药使用对作业人员健康影响等三方面进行综述探讨,以期为我国温室作业人员健康的防护研究提供相关的参考信息.

  4. Chromatic effects of the atmosphere on astronomical adaptive optics.

    Science.gov (United States)

    Devaney, Nicholas; Goncharov, Alexander V; Dainty, J Christopher

    2008-03-10

    The atmosphere introduces chromatic errors that may limit the performance of adaptive optics (AO) systems on large telescopes. Various aspects of this problem have been considered in the literature over the past two decades. It is necessary to revisit this problem in order to examine the effect on currently planned systems, including very high-order AO on current 8-10 m class telescopes and on future 30-42 m extremely large telescopes. We review the literature on chromatic effects and combine an analysis of all effects in one place. We examine implications for AO and point out some effects that should be taken into account in the design of future systems. In particular we show that attention should be paid to chromatic pupil shifts, which may arise in components such as atmospheric dispersion compensators.

  5. Prospective Turkish Elementary Science Teachers' Knowledge Level about the Greenhouse Effect and Their Views on Environmental Education in University

    Science.gov (United States)

    Kisoglu, Mustafa; Gürbüz, Hasan; Erkol, Mehmet; Akar, Muhammed Said; Akilli, Mustafa

    2010-01-01

    The fundamental factor of environmental education is teachers who are well-informed about environmental issues. This research aimed to determine prospective Turkish elementary science teachers' knowledge level about causes, consequences and reducing of the greenhouse effect and to investigate the effect of gender, information source and…

  6. Exploiting the igloo principle and greenhouse effect to regulate humidity and temperature

    Directory of Open Access Journals (Sweden)

    Prabhu Karthick

    2006-01-01

    Full Text Available Background: Toxic epidermal necrolysis can be fatal and nursing care with careful monitoring of temperature and humidity can improve survival rate. We adapted the greenhouse and igloo principle using a common hood to monitor the temperature and humidity. Methods: A small heater with a regulator was placed in a mini hood and temperature was recorded inside the uncovered hood and hood covered with green cloth and aluminium foil separately. The regular hood was placed over a volunteer and the temperature was measured inside the open hood and hood covered with green cloth and aluminium foil separately. The relative humidity was also monitored using Zeal mercury dry - wet bulb hygrometer. Results: Temperature increase was most marked in the foil-covered hood followed by cloth-covered hood, both with the heater and the volunteer. Similarly, in the volunteer study, the humidity was best maintained inside the aluminium foil-covered hood. Conclusion: We recommend the use of regular hood with suitable cover to monitor the humidity and temperature of patients with toxic epidermal necrolysis.

  7. Electric urban delivery trucks: energy use, greenhouse gas emissions, and cost-effectiveness.

    Science.gov (United States)

    Lee, Dong-Yeon; Thomas, Valerie M; Brown, Marilyn A

    2013-07-16

    We compare electric and diesel urban delivery trucks in terms of life-cycle energy consumption, greenhouse gas (GHG) emissions, and total cost of ownership (TCO). The relative benefits of electric trucks depend heavily on vehicle efficiency associated with drive cycle, diesel fuel price, travel demand, electric drive battery replacement and price, electricity generation and transmission efficiency, electric truck recharging infrastructure, and purchase price. For a drive cycle with frequent stops and low average speed such as the New York City Cycle (NYCC), electric trucks emit 42-61% less GHGs and consume 32-54% less energy than diesel trucks, depending upon vehicle efficiency cases. Over an array of possible conditions, the median TCO of electric trucks is 22% less than that of diesel trucks on the NYCC. For a drive cycle with less frequent stops and high average speed such as the City-Suburban Heavy Vehicle Cycle (CSHVC), electric trucks emit 19-43% less GHGs and consume 5-34% less energy, but cost 1% more than diesel counterparts. Considering current and projected U.S. regional electricity generation mixes, for the baseline case, the energy use and GHG emissions ratios of electric to diesel trucks range from 48 to 82% and 25 to 89%, respectively.

  8. Carbon stocks and sinks in forestry for the unitéd Kingdom greenhouse gas inventory. COST E21 Workshop. Contribution of forests and forestry to mitigate greenhouse effects. Joensuu (Finland. 28-30 Sep 2000

    Directory of Open Access Journals (Sweden)

    Milne R.

    2000-01-01

    Full Text Available Afforestation in the UK has been significant and continuing since 1920 (up to 30,000 ha per year. Planting data is used to drive a dynamic process-based carbon accounting model (C-Flow to estimate removals of atmospheric CO2 to these forests. It is assumed that the afforestation can be represented by the characteristics of Sitka spruce for conifers and beech for broadleaves. The present area of forest considered for these estimates is 1.6 millions ha. In 1990 the uptake to trees, litter, soil and products was 2.6 terragramme C, rising to 2.8 terragramme C in 1998. Deforestation is believed to be small. Supporting measurements show that the model predicts long term uptake by conifers well but that losses from planted peat shortly after establishment need further consideration. Process modelling of beech growth suggests that it is primarily dependant on atmospheric CO2 concentration and not on stomatal control per se. UK research priorities relevant to preparation of GHG (greenhouse gas Inventories are presented.

  9. Anthropogenic effects on greenhouse gas (CH{sub 4} and N{sub 2}O) emissions in the Guadalete River Estuary (SW Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Burgos, M.; Sierra, A.; Ortega, T.; Forja, J.M.

    2015-01-15

    Coastal areas are subject to a great anthropogenic pressure because more than half of the world's population lives in its vicinity causing organic matter inputs, which intensifies greenhouse gas emissions into the atmosphere. Dissolved concentrations of CH{sub 4} and N{sub 2}O have been measured seasonally during 2013 in the Guadalete River Estuary, which flows into the Cadiz Bay (southwestern Spanish coast). It has been intensely contaminated since 1970. Currently it receives wastewater effluents from cities and direct discharges from nearby agriculture crop. Eight sampling stations have been established along 18 km of the estuary. CH{sub 4} and N{sub 2}O were measured using a gas chromatograph connected to an equilibration system. Additional parameters such as organic matter, dissolved oxygen, nutrients and chlorophyll were determinate as well, in order to understand the relationship between physicochemical and biological processes. Gas concentrations increased from the River mouth toward the inner part, closer to the wastewater treatment plant discharge. Values varied widely within 21.8 and 3483.4 nM for CH{sub 4} and between 9.7 and 147.6 nM for N{sub 2}O. Greenhouse gas seasonal variations were large influenced by the precipitation regime, masking the temperature influence. The Guadatete Estuary acted as a greenhouse gas source along the year, with mean fluxes of 495.7 μmol m{sup −2} d{sup −1} and 92.8 μmol m{sup −2} d{sup −1} for CH{sub 4} and N{sub 2}O, respectively. - Highlights: • The estuary acts as a source of atmospheric methane and nitrous oxide. • Anthropogenic inputs affect the distribution of the greenhouse gases. • Dissolved gases presented an important longitudinal gradient. • Seasonal variations highly depended on the precipitation regimen.

  10. The effects of potential changes in United States beef production on global grazing systems and greenhouse gas emissions

    Science.gov (United States)

    Dumortier, Jerome; Hayes, Dermot J.; Carriquiry, Miguel; Dong, Fengxia; Du, Xiaodong; Elobeid, Amani; Fabiosa, Jacinto F.; Martin, Pamela A.; Mulik, Kranti

    2012-06-01

    We couple a global agricultural production and trade model with a greenhouse gas model to assess leakage associated with modified beef production in the United States. The effects on emissions from agricultural production (i.e., methane and nitrous oxide emissions from livestock and crop management) as well as from land-use change, especially grazing system, are assessed. We find that a reduction of US beef production induces net carbon emissions from global land-use change ranging from 37 to 85 kg CO2-equivalent per kg of beef annualized over 20 years. The increase in emissions is caused by an inelastic domestic demand as well as more land-intensive cattle production systems internationally. Changes in livestock production systems such as increasing stocking rate could partially offset emission increases from pasture expansion. In addition, net emissions from enteric fermentation increase because methane emissions per kilogram of beef tend to be higher globally.

  11. Atmospheric Chemistry of (CF3)2CF-C≡N: A Replacement Compound for the Most Potent Industrial Greenhouse Gas, SF6.

    Science.gov (United States)

    Sulbaek Andersen, Mads P; Kyte, Mildrid; Andersen, Simone Thirstrup; Nielsen, Claus J; Nielsen, Ole John

    2017-02-07

    FTIR/smog chamber experiments and ab initio quantum calculations were performed to investigate the atmospheric chemistry of (CF3)2CFCN, a proposed replacement compound for the industrially important sulfur hexafluoride, SF6. The present study determined k(Cl + (CF3)2CFCN) = (2.33 ± 0.87) × 10(-17), k(OH + (CF3)2CFCN) = (1.45 ± 0.25) × 10(-15), and k(O3 + (CF3)2CFCN) ≤ 6 × 10(-24) cm(3) molecule(-1) s(-1), respectively, in 700 Torr of N2 or air diluent at 296 ± 2 K. The main atmospheric sink for (CF3)2CFCN was determined to be reaction with OH radicals. Quantum chemistry calculations, supported by experimental evidence, shows that the (CF3)2CFCN + OH reaction proceeds via OH addition to -C(≡N), followed by O2 addition to -C(OH)═N·, internal H-shift, and OH regeneration. The sole atmospheric degradation products of (CF3)2CFCN appear to be NO, COF2, and CF3C(O)F. The atmospheric lifetime of (CF3)2CFCN is approximately 22 years. The integrated cross section (650-1500 cm(-1)) for (CF3)2CFCN is (2.22 ± 0.11) × 10(-16) cm(2) molecule(-1) cm(-1) which results in a radiative efficiency of 0.217 W m(-2) ppb(-1). The 100-year Global Warming Potential (GWP) for (CF3)2CFCN was calculated as 1490, a factor of 15 less than that of SF6.

  12. The conversion of grassland to acacia forest as an effective option for net reduction in greenhouse gas emissions.

    Science.gov (United States)

    de Godoi, Stefânia Guedes; Neufeld, Ângela Denise Hubert; Ibarr, Mariana Alves; Ferreto, Décio Oscar Cardoso; Bayer, Cimélio; Lorentz, Leandro Homrich; Vieira, Frederico Costa Beber

    2016-03-15

    This study aimed to evaluate the effect of forestation with leguminous Acacia mearnsii De Wild in native grasslands on the soil greenhouse (GHG) fluxes and their main driving factors. The experiment was conducted in the Brazilian Pampa over the period of one year in a six-year-old Acacia plantation, evaluating four treatments: Acacia (AM), Acacia with litter periodically removed (A-l), Acacia after harvest (AH) and native grassland (NG) (reference treatment). Air samples were obtained by the static chamber method, and gas concentrations were evaluated by gas chromatography. Soil and climate factors were monitored. The accumulated fluxes of methane (CH4) and nitrous oxide (N2O) were statistically similar between the soils in the AM and NG treatments, which tended to oxidize CH4 (-1445 and -1752 g C-CH4 ha(-1) yr(-1), respectively) and had low emission of N2O (242 and 316 g N-N2O ha(-1) yr(-1)), most likely influenced by the low water-filled pore space and the low content of mineral N in the soil. However, the soil in the AH treatment presented higher emissions of both gases, totaling 1889 g C-CH4 ha(-1) yr(-1) and 1250 g N-N2O ha(-1) yr(-1). Afforestation neither significantly affected the total organic C stocks nor their lability, keeping the C management index for the forested area similar to that in the NG treatment. The conversion from grassland to Acacia forest represents an effective option for mitigating the net reduction in greenhouse gas emissions, which is basically determined by C accumulation in biomass and wood products.

  13. Effect of furnace atmosphere on E-glass foaming

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong-Sang; Dutton, Bryan C.; Hrma, Pavel R.; Pilon, Laurent

    2006-12-01

    The effect of furnace atmosphere on E-glass foaming generated in crucible has been studied with a specific goal to understand the impact of increased water content on foaming in oxy-fired furnaces. E-glass foams were generated in a fused-quartz crucible located in a quartz window furnace equipped with video recording. The present study showed that humidity in the furnace atmosphere destabilizes foam, while other gases have little effect on foam stability. This study suggests that the higher foaming in oxy-fired furnace compared to air-fired is caused by the effect of water on early sulfate decomposition, promoting more efficient refining gas generation from sulfate (known as “dilution effect”).

  14. Atmospheric effects on Quaternary polarization encoding for free space communication

    Science.gov (United States)

    Soorat, Ram; Vudayagiri, Ashok

    2016-10-01

    We have simulated atmospheric effects such as fog and smoke in laboratory environment to simulate depolarisation due to atmospheric effects during a free space optical communi- cation. This has been used to study noise in two components of quaternary encoding for polarization shift keying. Individual components of a Quaternary encoding, such as vertical and horizontal as well as 45$^\\circ$ and 135$^\\circ$ , are tested separately and indicates that the depo- larization effects are different for these two situation. However, due to a differential method used to extract information bits, the protocol shows extremely low bit error rates. The information obtained is useful during deployment of a fully functional Quaternary encoded PolSK scheme in free space.

  15. Detection of non-standard atmospheric effects in FSO systems

    Science.gov (United States)

    Wilfert, Otakar; Poliak, Juraj; Barcík, Peter; Arce-Diego, José L.; Fanjul-Vélez, Félix; Salas-García, Irene; Ortega Quijano, Noé

    2013-09-01

    Modern free-space optical (FSO) communication systems in many aspects overcome wire or radio communications. They offer a license-free operation and a large bandwidth. Operation of outdoor FSO links struggles with many atmospheric phenomena that deteriorate phase and amplitude of the transmitted optical beam. Thanks to the recent advancing development, these effects are more or less well understood and described. Goal driven research increased the link availability. Besides increasing the availability of data links it is necessary to focus on the accuracy and reliability of testing optical links. Research of the data optical links is focused on the transmission of a large amount of data whereas the testing FSO link is designed to achieve maximal resolution and sensitivity thus improving accuracy and repeatability of the atmospheric effects measurement. Given the fact that testing links are located in the measured media, they are themselves influenced by it. Phenomena such as the condensation on transceiver windows (rain, frost) and the deviation of the optical beam path caused by the wind are referred to as non-standard effects. Non-standard effects never occur independently; therefore we must always verify the cross-sensitivity of the testing link. In the paper we respond to an increasing number of articles dealing with influence of the atmosphere on the link but ignoring the cross-sensitivity of the testing link on other variables than tested. In conclusion, we carry out qualitative and quantitative analysis of self-identified non-standard effects.

  16. Modelling the effect of the position of cooling elements on the vertical profile of transpiration in a greenhouse tomato crop

    NARCIS (Netherlands)

    Stanghellini, C.; Dieleman, J.A.; Driever, S.M.; Marcelis, L.F.M.

    2012-01-01

    Semi-closed greenhouse management may increase greenhouse productivity. However, it relies on the application of mechanical cooling. Cooling can be applied from above or below the canopy. The positioning of the cooling affects the vertical climate profile in the canopy. In order to determine how thi

  17. Development of greenhouse grown onion transplants and effect of plant density and fertilizer rate on marketable yield

    Science.gov (United States)

    Greenhouse grown onion (Allium cepa L.) transplants may have potential for use in production systems, but how they respond to cultural practices needs clarification. Seedlings of ‘Candy' and ‘Texas Grano 1015Y' were raised in a greenhouse. ‘Candy' seedlings were heavier than ‘Texas Grano 1015Y' se...

  18. Non-additive effects of litter diversity on greenhouse gas emissions from alpine steppe soil in Northern Tibet.

    Science.gov (United States)

    Chen, Youchao; Sun, Jian; Xie, Fangting; Yan, Yan; Wang, Xiaodan; Cheng, Genwei; Lu, Xuyang

    2015-12-04

    While litter decomposition is a fundamental ecological process, previous studies have mainly focused on the decay of single species. In this study, we conducted a litter-mixing experiment to investigate litter diversity effects on greenhouse gas (GHG) emissions from an alpine steppe soil in Northern Tibet. Significant non-additive effects of litter diversity on GHG dynamics can be detected; these non-additive effects were the result of species composition rather than species richness. Synergistic effects were frequent for CO2 and N2O emissions, as they were found to occur in 70.5% and 47.1% of total cases, respectively; antagonistic effects on CH4 uptake predominated in 60.3% of the cases examined. The degree of synergism and antagonism may be significantly impacted by litter chemical traits, such as lignin and N, lignin:N ratio, and total phenols during decomposition (P < 0.05). In addition, the relationship between chemical traits and litter-mixing effects changed over incubation time. Our study provides an opportunity to gain insight into the relationship between litter diversity and soil ecological processes. The results indicate that higher plant diversity may generally enhance CO2 and N2O emissions while inhibiting CH4 uptake; meanwhile, the direction and strength of non-additive effects appear to be related to litter chemical traits.

  19. Evaluation of residue management practices effects on corn productivity, soil quality, and greenhouse gas emissions

    Science.gov (United States)

    Guzman, Jose German

    The removal of crop residues left after harvest is being considered as a potential feedstock source for bioethanol production which can contribute to the reduction of fossil fuel use and net greenhouse gas (GHG). The objectives of this study were to: (i) examine how tillage, N fertilization rates, residue removal, and their interactions affect crop productivity, (ii) SOC and soil physical properties, and (iii) GHG emissions, and (iv) calculated a soil C budget to determine how much crop residue can be sustainably be removed in Central and Southwest Iowa. After three years of residue removal under different management practices, the findings of this study suggest that a portion of the corn residue that is left on the soil surface after harvest can be removed, with no negative impacts in the short term continuous corn yield in sites at Central and Southwest Iowa. However, significant decreases in SOC sequestration rates, microbial biomass-C, bulk density, soil penetration resistance, wet aggregate stability, and infiltration rates were observed, but varied with soil type and management practices. Additionally, soil surface CO2 and N2O emissions were responsive to management practices; primarily by altering soil temperature, soil water content, soil mineral N, and crop growth. Results from soil C budget show that in 2010 when corn growth was not water stressed (lack of moisture), approximately 35 and 30% of the residue could be sustainably removed in the Central and Southwest sites, respectively. In 2011, drier soil conditions resulted in approximately 2 and 49% of the residue could be sustainably removed in the Central and Southwest sites, respectively.

  20. A perspective on cost-effectiveness of greenhouse gas reduction solutions in water distribution systems

    Science.gov (United States)

    Hendrickson, Thomas P.; Horvath, Arpad

    2014-01-01

    Water distribution systems (WDSs) face great challenges as aging infrastructures require significant investments in rehabilitation, replacement, and expansion. Reducing environmental impacts as WDSs develop is essential for utility managers and policy makers. This study quantifies the existing greenhouse gas (GHG) footprint of common WDS elements using life-cycle assessment (LCA) while identifying the greatest opportunities for emission reduction. This study addresses oversights of the related literature, which fails to capture several WDS elements and to provide detailed life-cycle inventories. The life-cycle inventory results for a US case study utility reveal that 81% of GHGs are from pumping energy, where a large portion of these emissions are a result of distribution leaks, which account for 270 billion l of water losses daily in the United States. Pipe replacement scheduling is analyzed from an environmental perspective where, through incorporating leak impacts, a tool reveals that optimal replacement is no more than 20 years, which is in contrast to the US average of 200 years. Carbon abatement costs (CACs) are calculated for different leak reduction scenarios for the case utility that range from -130 to 35 t-1 CO2(eq). Including life-cycle modeling in evaluating pipe materials identified polyvinyl chloride (PVC) and cement-lined ductile iron (DICL) as the Pareto efficient options, however; utilizing PVC presents human health risks. The model developed for the case utility is applied to California and Texas to determine the CACs of reducing leaks to 5% of distributed water. For California, annual GHG savings from reducing leaks alone (3.4 million tons of CO2(eq)) are found to exceed California Air Resources Board’s estimate for energy efficiency improvements in the state’s water infrastructure.

  1. Effects of CO[sub 2] concentration on photosynthesis, transpiration and production of greenhouse fruit vegetable crops

    Energy Technology Data Exchange (ETDEWEB)

    Nederhoff, E.M.

    1994-10-25

    The effect of the CO[sub 2] concentration of the greenhouse air (C) in the range 200 to 1100 [mu]mol mol[sup -1] was investigated in tomato (Lycopersicon esculentum Mill.), cucumber (Cucumis sativus L.), sweet pepper (Capsicum annuum L.) and eggplant (Solanum melongena L.), grown in greenhouses. The effect of C on canopy net photosynthetic CO[sub 2] assimilation rate (or photosynthesis, P) was expressed by a set of regression equations, relating P to PAR, C and LAI. A rule of thumb ('CO[sub 2]-rule') was derived, approximating the relative increase of P caused by additional CO[sub 2] at a certain C. This CO[sub 2]-rule is: X = (1000/C)[sup 2] * 1.5 (X in % per 100 [mu]mol[sup -1], and C in [mu]mol mol[sup -1]). Two models for canopy photosynthesis were examined by comparing them with the experimental photosynthesis data. No 'midday depression' in P was observed. The effects of C on leaf conductance (g) and on rate of crop transpiration (E) were investigated. An increase of 100 I[mu]mol mol[sup -1] ' in C reduced g by about 3-4% in sweet pepper, tomato and cucumber and by about 11% in eggplant. The effect of C on E was analyzed by combining the regression equation for g with the Penman-Monteith equation for E. C had only a relatively small effect on E, owing to thermal and hydrological feedback effects. The decoupling of g and E was quantified. No time-dependent variation or 'midday depression' in E was observed, and no significant effect of C on average leaf temperature was established. In five experiments, the effect of C on growth and production and on specific features were analyzed; fruit production (dry weight) was most affected by C in sweet pepper; fresh weight fruit production per unit CO[sub 2] was highest in cucumber; fruit quality was not influenced by C. High C promoted the 'short leaves syndrome' in tomato and 'leaf tip chlorosis' in eggplant, probably related to calcium and boron translocation

  2. French program for greenhouse effect prevention; Programme de lutte contre l'effet de serre. A grands maux, petits remedes

    Energy Technology Data Exchange (ETDEWEB)

    Gaullier, V.; Guez, M

    2000-03-01

    The government program to slowdown the greenhouse effect follows 3 axis: a policy of favoring the reduction of energy consumption, a taxation of the emission of greenhouse gases (with the setting of rights to polluting which can be bought and sold by firms) and actions in the agriculture sector: reduction of methane emission in intensive animal husbandry and afforestation of 20000 hectares surface each year till 2006. Transport means such as individual cars and trucks are spared by this program while they are the first polluters. (A.C.)

  3. Evaluation of the greenhouse effect. Climate changes: from models to negotiations; Le point sur l`effet de serre. Changement de climat: des modeles aux negociations

    Energy Technology Data Exchange (ETDEWEB)

    Cointe, R. [Ministere de l`Environnement, 75 - Paris (France). Mission interministerielle de l`effet de serre

    1997-01-01

    This paper takes stock of scientific works and negotiations in progress about climatic changes linked with greenhouse effect. The scientists opinion about the noxiousness of greenhouse gases (CO{sub 2}, CH{sub 4}, N{sub 2}O, tropospheric O{sub 3}, CFC and their substitutes) inducing climate warming (0,5 deg. C as an average during the 20. Century) is reported. The forecasting about the evolution and organisation of the international effort (United Nations Climate Convention, Berlin`s Commission), and the French contribution on this topic is analyzed. (N.K.).

  4. Greenhouse impact of Finnish peatlands 1900-2100

    Energy Technology Data Exchange (ETDEWEB)

    Laine, J.; Minkkinen, K. [Helsinki Univ. (Finland). Dept. of Ecology; Tolonen, K.; Turunen, J. [Joensuu Univ. (Finland). Dept. of Biology; Martikainen, P.; Nykaenen, H. [National Public Health Inst. Kuopio (Finland). Dept. of Environmental Microbiology; Sinisalo, J.; Savolainen, I. [VTT Energy, Espoo (Finland)

    1996-12-31

    Northern peatlands are significant in regulating the global climate. While sequestering carbon dioxide (CO{sub 2}, ca. 100 Tg C a{sup -} {sup 1}), these peatlands release cat 24-39 Tg methane (CH{sub 4}) annually to the atmosphere. This is 5-15 % of the annual anthropogenic and 10-35 % of the annual natural CH4 emissions to the atmosphere. The greenhouse gas balance of peatlands may change as a consequence of water level drawdown after land use change, or if summers become warmer and drier, as has been predicted for high latitudes after climatic warming. Currently, some 15 million hectares of northern peatlands and other wetlands have been drained for forestry. More than 90 % of this area is found in Scandinavia and the former Soviet Union. The area drained annually has, however, been declining during the last two decades and, in Finland for instance the annual drained area of nearly 300 000 hectares in the late 1960`s has decreased to cat 35 000 hectares in the early 1990`s. Radiative forcing is the change in the radiative energy balance at the tropopause and it is the driving force behind the greenhouse effect. It is a common quantity for most greenhouse gases and takes into account the dynamics of the greenhouse impact. Radiative forcing model was used to compute the greenhouse impact of the drainage of the peatlands, combining the effects of CO{sub 2} and CH4 balances; N{sub 2}O was not included in the calculations because its contribution is minor. (14 refs.)

  5. No Effect Level of Co-Composted Biochar on Plant Growth and Soil Properties in a Greenhouse Experiment

    Directory of Open Access Journals (Sweden)

    Hardy Schulz

    2014-01-01

    Full Text Available It is claimed that the addition of biochar to soil improves C sequestration, soil fertility and plant growth, especially when combined with organic fertilizers such as compost. However, little is known about agricultural effects of small amounts of composted biochar. This greenhouse study was carried out to examine effects of co-composted biochar on oat (Avena sativa L. yield in both sandy and loamy soil. The aim of this study was to test whether biochar effects can be observed at very low biochar concentrations. To test a variety of application amounts below 3 Mg biochar ha−1, we co-composted five different biochar concentrations (0, 3, 5, 10 kg Mg−1 compost. The biochar-containing compost was applied at five application rates (10, 50, 100, 150, 250 Mg ha−1 20 cm−1. Effects of compost addition on plant growth, Total Organic Carbon, Ntot, pH and soluble nutrients outweighed the effects of the minimal biochar amounts in the composted substrates so that a no effect level of biochar of at least 3 Mg ha−1 could be estimated.

  6. Comparative study of rhizobacterial communities in pepper greenhouses and examination of the effects of salt accumulation under different cropping systems.

    Science.gov (United States)

    Hahm, Mi-Seon; Son, Jin-Soo; Kim, Byung-Soo; Ghim, Sa-Youl

    2017-03-01

    This study compared rhizobacterial communities in pepper greenhouses under a paddy-upland (rice-pepper) rotational system (PURS) and a monoculture repeated cropping system (RCS) and examined adverse effects of high salinity on soil properties. The following soil properties were analyzed: electrical conductivity (EC), pH, concentration of four cations (Na, Ca, Mg, and K), total nitrogen, and organic matter content. Rhizobacterial communities were analyzed using culture-based and culture-independent (pyrosequencing) methods. In addition, all culturable bacteria isolated from each soil sample were tested for traits related to plant growth promotion. The EC of rhizospheric soils was 5.32-5.54 dS/m for the RCS and 2.05-2.19 dS/m for the PURS. The culture-based method indicated that the bacterial communities and bacterial characteristics were significantly more diverse in the PURS soil than in the RCS soil. The pyrosequencing data also indicated that the richness and diversity of bacterial communities were greater in the PURS soil. Proteobacteria was the most abundant phylum in soil samples under both cropping systems. However, Firmicutes and Gemmatimonadetes were more prevalent in the RCS soil, while the PURS soil contained a greater number of Chloroflexi. Spearman's correlation coefficients showed that soil EC was significantly positively correlated with the abundance of Firmicutes and Gemmatimonadetes and negatively correlated with the abundance of Acidobacteria, Chloroflexi, and Deltaproteobacteria. This is the first study on the rhizobacterial communities in pepper greenhouses under two different cropping systems using both culture- and pyrosequencing-based methods.

  7. The effect of atmospheric pressure on ventricular assist device output.

    Science.gov (United States)

    Goto, Takeshi; Sato, Masaharu; Yamazaki, Akio; Fukuda, Wakako; Watanabe, Ken-Ichi; Daitoku, Kazuyuki; Minakawa, Masahito; Fukui, Kozo; Suzuki, Yasuyuki; Fukuda, Ikuo

    2012-03-01

    The effect of cabin pressure change on the respiratory system during flight is well documented in the literature, but how the change in atmospheric pressure affects ventricular assist device (VAD) output flow has not been studied yet. The purpose of our study was to evaluate the change in VAD output using a mock circulatory system in a low-pressure chamber mimicking high altitude. Changes in output and driving pressure were measured during decompression from 1.0 to 0.7 atm and pressurization from 0.7 to 1.0 atm. Two driving systems were evaluated: the VCT system and the Mobart system. In the VCT system, output and driving pressure remained the same during decompression and pressurization. In the Mobart system, the output decreased as the atmospheric pressure dropped and recovered during pressurization. The lowest output was observed at 0.7 atm, which was 80% of the baseline driven by the Mobart system. Under a practical cabin pressure of 0.8 atm, the output driven by the Mobart system was 90% of the baseline. In the Mobart system, the output decreased as the atmospheric pressure dropped, and recovered during pressurization. However, the decrease in output was slight. In an environment where the atmospheric pressure changes, it is necessary to monitor the diaphragmatic motion of the blood pump and the driving air pressure, and to adjust the systolic:diastolic ratio as well as the positive and negative pressures in a VAD system.

  8. Monitoring the effects of atmospheric ethylene near polyethylene manufacturing plants with two sensitive plant species

    Energy Technology Data Exchange (ETDEWEB)

    Tonneijck, A.E.G.; Berge, W.F. ten; Jansen, B.P

    2003-05-01

    Atmospheric ethylene from polyethylene manufacturing plants adversely affected the number of flowers and growth of field-grown marigold and petunia. - Data of a multi-year (1977-1983) biomonitoring programme with marigold and petunia around polyethylene manufacturing plants was analysed to assess plant responses to atmospheric ethylene and to determine the area at risk for the phytotoxic effects of this pollutant. In both species, flower formation and growth were severely reduced close to the emission sources and plant performance improved with increasing distance. Plants exposed near the border of the research area had more flowers than the unexposed control while their growth was normal. Measurements of ethylene concentrations at a border site revealed that the growing season mean was 61.5 {mu}g m{sup -3} in 1982 and 15.6 {mu}g m{sup -3} in 1983. In terms of number of flowers, petunia was more sensitive than marigold and adverse effects were observed within ca. 400 m distance from the sources for marigold and within ca. 460 m for petunia. The area at risk (ca. 870 m) for ethylene-induced growth reduction was also limited to the industrial zone. Plants were more sensitive to ethylene in terms of growth reduction than in terms of inhibition of flowering. In the Netherlands, maximum permissible levels of ethylene are currently based on information from laboratory and greenhouse studies. Our results indicate that these levels are rather conservative in protecting field-grown plants against ethylene-induced injury near polyethylene manufacturing plants.

  9. Modeling atmospheric effects of the September 1859 Solar Flare

    CERN Document Server

    Thomas, B; Melott, A; Thomas, Brian; Jackman, Charles; Melott, Adrian

    2006-01-01

    We have modeled atmospheric effects, especially ozone depletion, due to a solar proton event which probably accompanied the extreme magnetic storm of 1-2 September 1859. We use an inferred proton fluence for this event as estimated from nitrate levels in Greenland ice cores. We present results showing production of odd nitrogen compounds and their impact on ozone. We also compute rainout of nitrate in our model and compare to values from ice core data.

  10. Can the Solid State Greenhouse Effect Produce ~100 Year Cycles in the Mars South Polar Residual CO2 Ice Cap?

    Science.gov (United States)

    Line, M. R.; Ingersoll, A. P.

    2010-12-01

    Malin et al. (2001) reported that the south perennial cap consists of quasi-circular pits ~8 meters deep, with a flat surface in between. The walls of the pits are retreating at a rate of 1 to 3 meters per year. Byrne and Ingersoll (2003a, 2003b) showed evidence that the floors of the pits are water ice and the upper layer is CO2. This layer will be gone in a few Martian centuries, if the observations are taken at face value. This raises some difficult questions: How likely is it that mankind would be witnessing the final few hundred years of the residual CO2 frost on Mars? Can one imagine extreme weather events that could recharge the residual CO2 frost once it is gone? Both seem unlikely, and we propose a different mechanism. Kieffer et al. (2000) showed that sunlight can penetrate several meters through the seasonal CO2 frost, where it warms the surface below. We have observational evidence that the same is happening in the perennial CO2 frost. Further, we have a model that shows how this "solid-state greenhouse" can lead to cyclic behavior, in which layers of CO2 build up on a water ice substrate, are heated internally by sunlight and lose mass from within. Eventually the layer becomes too weak to support itself, and it collapses to form pits. Then a new CO2 layer accumulates and the process repeats. Our study addresses fundamental questions of long-term stability of the Martian polar caps and how the caps control the atmospheric pressure. Instead of invoking extreme climate events to explain the data, we propose that processes within the frost itself can lead to cyclic growth and collapse of the pits. Our model implies that there is no long-term change in the ~8 meter layer of CO2 and no extreme weather events to make it change.

  11. 全球变暖背景下温室效应的光谱能量分布分析%Analysis on Spectral Energy Distribution of Greenhouse Effect Under Global Warming Background

    Institute of Scientific and Technical Information of China (English)

    高凤玲; 崔国民; 陶乐仁; 华泽钊; 黄晓璜

    2014-01-01

    In a one⁃dimensional radiation transfer model, energy distribution and spectral absorption mechanism of greenhouse effect under Pre⁃Industrial and current atmospheric compositions were analyzed. Coupling mechanism between greenhouse effect and surface temperature was investigated on the basis of greenhouse gas concentrations at current level. It shows that warm environment before Industrial Revolution is mainly due to three strong absorption bands of greenhouse gases, which are (100-370) cm-1 , (640-710) cm-1 and (1 370-2 000) cm-1 respectively. However, current global warming is originated from weak absorption bands of greenhouse gases, that is, radiation absorptions by (370-640) cm-1and (710-1 370) cm-1. Contributions to greenhouse effect increment of these weak bands after Industrial Revolution are 25% and 55% respectively. With rising temperature, contribution of right side of the earth’ s radiation peak wavenumber to total greenhouse effect shows positive change, while contribution of left side shows negative change.%利用一维辐射传递方程及LBLRTM逐线积分模式建立计算模型,对工业革命前与目前大气构成情况下温室效应的能量分布及其光谱吸收机理进行分析,在保持温室气体浓度为当前水平的基础上,研究温室效应能量分布与地表温度之间的相互耦合机理。结果表明:工业革命前地球的温暖环境主要来自于大气温室气体的(100~370) cm-1、(640~710) cm-1以及(1370~2000) cm-1三个强吸收带对于地球长波辐射的吸收,而地球当前的变暖则源自于大气的(370~640) cm-1和(710~1370) cm-1两个弱吸收带的作用,其对工业革命以来所额外增加的温室效应贡献分别达到了25%和55%;地表温度升高,温室效应在全波段范围内也会随之增强,但不同谱带处的温室效应贡献以地球平均温度所对应的辐射峰值波数为界线,峰值波数右侧的

  12. The effect of type and ratio of vermicompost on selected growth indices and nutrients content of tomato at greenhouse conditions

    Directory of Open Access Journals (Sweden)

    M.H. Rasouli-Sadaghiani

    2016-02-01

    Full Text Available This study was conducted to investigate the effect of type and ratio of vermicompost on tomato growth, with five different types of vermicompost (platanus leaves, maple leaves, pruning apple trees and grape, waste of herbal extracts and azolla residues and four ratios of vermicompost to peat and perlite (2:1 v/v as 0, 1:3, 2:3 and 3:3, at greenhouse conditions. Results showed that type of vermicompost had a significant effect (P≤ 0.05 on plant height, shoot dry weight, root dry weight, number of internodes and stem diameter. The interaction between type and ratio of vermicompost had significant effect on root and shoot dry weight, stem diameter, nitrogen (N percent, and potassium (K percent. The highest effect on shoot dry weight, stem diameter and the N percentage was observed in the ratio of 2:3 vermicompost of azolla residues. The amount of K in the ratio of 2:3 vermicompost of maple leaves increased 66.18% as compared to the control treatment. Also, different ratios of vermicompost increased percentage of phosphorus and concentration of iron and zinc, as compared to peat+ perlite treatment. Generally, different types and ratios of vermicompost compared to peat+ perlite medium had a positive effect on growth indices and mineral concentration in the tomato plant.

  13. The effect of application method on the temporal and spatial distribution of neonicotinoid insecticides in greenhouse zinnia and impact on aphid populations

    Science.gov (United States)

    Greenhouse trials were designed to evaluate the effect the application technique would have on temporal and spatial movement of neonicotinoid insecticides imidacloprid and thiamethoxam through plant tissue. Mature Zinnia elegans plants were treated by either a soil drench of neonicotinoid insectici...

  14. Concept Formation in Environmental Education: 14-Year Olds' Work on the Intensified Greenhouse Effect and the Depletion of the Ozone Layer. Research Report

    Science.gov (United States)

    Osterlind, Karolina

    2005-01-01

    A case study is presented describing the work of three pupils in the upper level of compulsory school. The pupils were learning about the intensified greenhouse effect and the depletion of the ozone layer. In their work, the need for certain domain-specific knowledge becomes apparent; for example, understanding such concepts as photosynthesis,…

  15. Evaluation of the Knowledge and Misconceptions of Science Teacher Candidates in Turkey Regarding the Greenhouse Effect through the Use of Drawings

    Science.gov (United States)

    Aksan, Zeynep; Çelikler, Dilek

    2015-01-01

    The aim of this study was to identify, through the use drawings, the knowledge and misconceptions of science teacher candidates regarding the greenhouse effect, and to thereby categorize their level of knowledge on this subject. The study was conducted with a group of 327 science teacher candidates. In this study, science teacher candidates were…

  16. Conceptions of Knowledge in Research on Students' Understanding of the Greenhouse Effect: Methodological Positions and Their Consequences for Representations of Knowing

    Science.gov (United States)

    Jakobsson, Anders; Makitalo, Asa; Saljo, Roger

    2009-01-01

    Much of the research on students' understanding of the greenhouse effect and global warming reports poor results. Students are claimed to hold misconceptions and naive beliefs, and the impact of teaching on their conceptions is also low. In the present study, these results are called into question, and it is argued that they may to a large extent…

  17. Soil-atmosphere fluxes of the greenhouse gases N2O, CO2 and CH4 from a long term compost experiment in Austria.

    Science.gov (United States)

    Spann, Caroline; Spiegel, Heide; Kitzler, Barbara

    2016-04-01

    The application of composts as fertilizers is becoming increasingly important to achieve a closed-loop economy. However, greenhouse gas (GHG) emissions, especially N2O, from agricultural fields may increase as well. In this study different compost types and N amounts were investigated, especially in terms of their GHG fluxes. We used the closed chamber method to estimate GHG flux rates over one vegetation period from an agricultural soil fertilized with different compost types. The study was conducted on a long term compost experiment site near Linz (Austria) with a crop rotation. The soil is a loamy silt and in 2015 maize was planted. Six different compost treatments were investigated. Organic waste compost (OWC) and farmyard manure compost (FMC) was applied with nitrogen concentrations of 175 (OWC1, FYC1) and 525 kg N ha-1 (OWC3, FYC3). Two compost treatments were fertilized additionally with 80 kg N ha.1 mineral fertilizer (OWC2, FYC2). One treatment (TN) was fertilized only with mineral fertilizer (120 kg N ha-1) and one treatment was not fertilized at all (C). Additionally to the GHG flux rates, ammonium and nitrate content, microbial biomass C and N and different enzyme activities were analysed in the top soil. Nitrous oxide (N2O) was emitted over the entire vegetation period with highest fluxes from April until June, until the plants have been established sufficiently. Overall, at the FMC treatments (FYC2, FYC3) highest fluxes were measured. Compared to FMC, lower N2O emissions were measured from the OWC treatments. The combination of compost and mineral N fertilization resulted in the highest N2O emissions, especially after precipitation events. The treatments OWC1 and FYC1 were not different from the control. Methane (CH4) was mainly taken up at all treatments, but uptake rates were lower at the high N input sites (OWC3, FYC3) with no differences between the compost types. No significant differences were found in the soil respiration rates.

  18. A sonic boom propagation model including mean flow atmospheric effects

    Science.gov (United States)

    Salamone, Joe; Sparrow, Victor W.

    2012-09-01

    This paper presents a time domain formulation of nonlinear lossy propagation in onedimension that also includes the effects of non-collinear mean flow in the acoustic medium. The model equation utilized is an augmented Burgers equation that includes the effects of nonlinearity, geometric spreading, atmospheric stratification, and also absorption and dispersion due to thermoviscous and molecular relaxation effects. All elements of the propagation are implemented in the time domain and the effects of non-collinear mean flow are accounted for in each term of the model equation. Previous authors have presented methods limited to showing the effects of wind on ray tracing and/or using an effective speed of sound in their model equation. The present work includes the effects of mean flow for all terms included in the augmented Burgers equation with all of the calculations performed in the time-domain. The capability to include the effects of mean flow in the acoustic medium allows one to make predictions more representative of real-world atmospheric conditions. Examples are presented for nonlinear propagation of N-waves and shaped sonic booms. [Work supported by Gulfstream Aerospace Corporation.

  19. What is the greenhouse effect?: its consequences on the future climate; Qu'est-ce que l'effet de serre?: ses consequences sur l'avenir du climat

    Energy Technology Data Exchange (ETDEWEB)

    Petit, M.

    2003-07-01

    In this book the greenhouse effect is explained and detailed from the knowledge of scientists. It presents also what could be, at short-dated and middle-dated, the climatic changes and their consequences if the greenhouse effect resulting from the human activities is not quickly stabilized. (A.L.B.)

  20. Veracruz State Preliminary Greenhouse Gases Emissions Inventory

    Science.gov (United States)

    Welsh Rodriguez, C.; Rodriquez Viqueira, L.; Guzman Rojas, S.

    2007-05-01

    At recent years, the international organisms such as United Nations, has discussed that the temperature has increased slightly and the pattern of precipitations has changed in different parts of the world, which cause either extreme droughts or floods and that the extreme events have increased. These are some of the risks of global climate change because of the increase of gas concentration in the atmosphere such as carbon dioxides, nitrogen oxides and methane - which increase the greenhouse effect. Facing the consequences that could emerge because of the global temperature grown, there is a genuine necessity in different sectors of reduction the greenhouse gases and reduced the adverse impacts of climate change. To solve that, many worldwide conventions have been realized (Rio de Janeiro, Kyoto, Montreal) where different countries have established political compromises to stabilize their emissions of greenhouse gases. The mitigation and adaptation policies merge as a response to the effects that the global climate change could have, on the humans as well as the environment. That is the reason to provide the analysis of the areas and geographic zones of the country that present major vulnerability to the climate change. The development of an inventory of emissions that identifies and quantifies the principal sources of greenhouse gases of a country, and also of a region is basic to any study about climate change, also to develop specific political programs that allow to preserve and even improve a quality of the atmospheric environment, and maybe to incorporate to international mechanisms such as the emissions market. To estimate emissions in a systematic and consistent way on a regional, national and international level is a requirement to evaluate the feasibility and the cost-benefit of instrumented possible mitigation strategies and to adopt politics and technologies to reduce emissions. Mexico has two national inventories of emissions, 1990 and 1995, now it is

  1. Modeling of Atmospheric Turbulence Effect on Terrestrial FSO Link

    Directory of Open Access Journals (Sweden)

    A. Prokes

    2009-04-01

    Full Text Available Atmospheric turbulence results in many effects causing fluctuation in the received optical power. Terrestrial laser beam communication is affected above all by scintillations. The paper deals with modeling the influence of scintillation on link performance, using the modified Rytov theory. The probability of correct signal detection in direct detection system in dependence on many parameters such as link distance, power link margin, refractive-index structure parameter, etc. is discussed and different approaches to the evaluation of scintillation effect are compared. The simulations are performed for a horizontal-path propagation of the Gaussian-beam wave.

  2. 77 FR 10373 - Greenhouse Gas Reporting Program: Electronics Manufacturing: Revisions to Heat Transfer Fluid...

    Science.gov (United States)

    2012-02-22

    ... AGENCY 40 CFR Part 98 RIN 2060-AR09 Greenhouse Gas Reporting Program: Electronics Manufacturing... category of the Greenhouse Gas Reporting Rule related to fluorinated heat transfer fluids. More... INFORMATION CONTACT: Carole Cook, Climate Change Division, Office of Atmospheric Programs...

  3. Effects of nitrogen fertilizer sources and tillage practices on greenhouse gas emissions in paddy fields of central China

    Science.gov (United States)

    Zhang, Z. S.; Chen, J.; Liu, T. Q.; Cao, C. G.; Li, C. F.

    2016-11-01

    The effects of nitrogen (N) fertilizer sources and tillage practices on greenhouse gas (GHG) emission have been well elucidated separately. However, it is still remained unclear regarding the combined effects of N fertilization and tillage practices on the global warming potential (GWP) and net ecosystem economic budget (NEEB) in paddy fields. In this paper, a 2-year field experiment was performed to investigate the effects of N fertilizer sources (N0, no N; IF, 100% N from chemical fertilizer; SRIF, 50% N from slow-release fertilizer and 50% N from chemical fertilizer; OF, 100% N from organic fertilizer; OFIF, 50% N from organic fertilizer and 50% N from chemical fertilizer) and tillage practices (CT, conventional intensive tillage; NT, no-tillage) on the emissions of methane (CH4) and nitrous oxide (N2O), GWP, greenhouse gas intensity (GHGI), and NEEB in paddy fields of central China. Compared with N0 treatment, IF, SRIF, OF and OFIF treatments greatly enhanced the cumulative seasonal CH4 emissions (by 54.7%, 41.7%, 51.1% and 66.0%, respectively) and N2O emissions (by 164.5%, 93.4%, 130.2% and 251.3%, respectively). NT treatment significantly decreased the GWP and GHGI compared with CT treatment. On the other hand, NT treatment significantly decreased CH4 emissions by 8.5-13.7%, but did not affect N2O emissions relative to CT treatment. Application of N fertilizers significantly increased GWP and GHGI. It was worth noting that the combined treatment of OFIF and NT resulted in the second-highest GWP and GHGI and the largest NEEB among all treatments. Therefore, our results suggest that OFIF combined with NT is an eco-friendly strategy to optimize the economic and environmental benefits of paddy fields in central China. Although the treatment of SRIF plus NT showed the lowest GWP and GHGI and the highest grain yield among all treatments, it led to the lowest NEEB due to its highest fertilizer cost. These results indicate that the government should provide

  4. Research Progress of Reference Materials for Atmospheric Background Greenhouse Gases Measurement%大气本底温室气体测量标准物质研究进展

    Institute of Scientific and Technical Information of China (English)

    毕哲; 周泽义; 王德发; 王星

    2014-01-01

    The research progresses of the preparation technology for greenhouse gas standard materials were reviewed. The type and the uncertainty of green house gas standard materials were classified. The feasibility of different preparation technologies to meet demand of greenhouse gas monitoring was also studied. The comprehensive effects of dilution operation,the pretreatment of gas cylinder and the choice of pipeline materials on the stability of standard substance were discussed. The difference of the traceability system between BIPM and WMO was compared.%综述了温室气体标准物质的制备技术与研究进展。归纳了温室气体标准物质种类和量值不确定度的要求,考察了各种配气技术对温室气体监测需求的适用性。综合讨论了配气技术中的稀释操作、钢瓶处理方式及阀门管线材质对温室气体标准物质量值稳定性的影响,并比较了 BIPM 和 WMO 量传体系的差异。

  5. Measurement of atmospheric neutrino oscillations and matter effects with PINGU

    Energy Technology Data Exchange (ETDEWEB)

    Coenders, Stefan; Euler, Sebastian; Krings, Kai; Vehring, Markus; Wallraff, Marius; Wiebusch, Christopher [RWTH Aachen Univ. (Germany). III. Physikalisches Inst.; Collaboration: IceCube-Collaboration

    2013-07-01

    With IceCube's low-energy extension DeepCore the first significant effects of atmospheric neutrino oscillations have been observed. The planned ''Precision Icecube Next Generation Upgrade'' (PINGU) inside DeepCore will lower the energy threshold to a few GeV, where matter effects of neutrino oscillations have to be taken into account. The Mikheyev-Smirnov-Wolfenstein (MSW) effect modifies the mixing between flavor and mass eigenstates of the neutrinos, resulting in stronger oscillations. Furthermore, neutrinos when passing through the Earth core experience parametric enhancement due to multiple discontinuities in the electron density. In this talk the effects of matter oscillations and the capabilities to measure these effects with PINGU are investigated.

  6. The Dynamic Greenhouse Challenge

    Science.gov (United States)

    Roman, Harry T.

    2010-01-01

    Greenhouses are marvelous devices, allowing one to enjoy the flower spectacle of summer all year round. At night, greenhouses use supplemental heat to keep the fragile plants warm. Over the last 30 years, greenhouse technology has undergone many changes, with the structures being automated and monitored and low-cost plastic structures emerging as…

  7. Removing atmosphere loading effect from GPS time series

    Science.gov (United States)

    Tiampo, K. F.; Samadi Alinia, H.; Samsonov, S. V.; Gonzalez, P. J.

    2015-12-01

    The GPS time series of site position are contaminated by various sources of noise; in particular, the ionospheric and tropospheric path delays are significant [Gray et al., 2000; Meyer et al., 2006]. The GPS path delay in the ionosphere is largely dependent on the wave frequency whereas the delay in troposphere is dependent on the length of the travel path and therefore site elevation. Various approaches available for compensating ionosphere path delay cannot be used for removal of the tropospheric component. Quantifying the tropospheric delay plays an important role for determination of the vertical GPS component precision, as tropospheric parameters over a large distance have very little correlation with each other. Several methods have been proposed for tropospheric signal elimination from GPS vertical time series. Here we utilize surface temperature fluctuations and seasonal variations in water vapour and air pressure data for various spatial and temporal profiles in order to more accurately remove the atmospheric path delay [Samsonov et al., 2014]. In this paper, we model the atmospheric path delay of vertical position time series by analyzing the signal in the frequency domain and study its dependency on topography in eastern Ontario for the time period from January 2008 to December 2012. Systematic dependency of amplitude of atmospheric path delay as a function of height and its temporal variations based on the development of a new, physics-based model relating tropospheric/atmospheric effects with topography and can help in determining the most accurate GPS position.The GPS time series of site position are contaminated by various sources of noise; in particular, the ionospheric and tropospheric path delays are significant [Gray et al., 2000; Meyer et al., 2006]. The GPS path delay in the ionosphere is largely dependent on the wave frequency whereas the delay in troposphere is dependent on the length of the travel path and therefore site elevation. Various

  8. CO2, the greenhouse effect and global warming: from the pioneering work of Arrhenius and Callendar to today's Earth System Models.

    Science.gov (United States)

    Anderson, Thomas R; Hawkins, Ed; Jones, Philip D

    2016-09-01

    Climate warming during the course of the twenty-first century is projected to be between 1.0 and 3.7°C depending on future greenhouse gas emissions, based on the ensemble-mean results of state-of-the-art Earth System Models (ESMs). Just how reliable are these projections, given the complexity of the climate system? The early history of climate research provides insight into the understanding and science needed to answer this question. We examine the mathematical quantifications of planetary energy budget developed by Svante Arrhenius (1859-1927) and Guy Stewart Callendar (1898-1964) and construct an empirical approximation of the latter, which we show to be successful at retrospectively predicting global warming over the course of the twentieth century. This approximation is then used to calculate warming in response to increasing atmospheric greenhouse gases during the twenty-first century, projecting a temperature increase at the lower bound of results generated by an ensemble of ESMs (as presented in the latest assessment by the Intergovernmental Panel on Climate Change). This result can be interpreted as follows. The climate system is conceptually complex but has at its heart the physical laws of radiative transfer. This basic, or "core" physics is relatively straightforward to compute mathematically, as exemplified by Callendar's calculations, leading to quantitatively robust projections of baseline warming. The ESMs include not only the physical core but also climate feedbacks that introduce uncertainty into the projections in terms of magnitude, but not sign: positive (amplification of warming). As such, the projections of end-of-century global warming by ESMs are fundamentally trustworthy: quantitatively robust baseline warming based on the well-understood physics of radiative transfer, with extra warming due to climate feedbacks. These projections thus provide a compelling case that global climate will continue to undergo significant warming in response

  9. [Soil greenhouse gases emission from an Acacia crassicarpa plantation under effects of understory removal and Cassia alata addition].

    Science.gov (United States)

    Li, Hai-Fang; Zhang, Xing-Feng

    2010-03-01

    Forest soil is one of the main sources of greenhouse gases CO2, CH4, and N2O. By using static chamber and GS technique, this paper measured in situ the CO2, CH4, and N2O fluxes of Acacia crassicarpa plantation in Heshan Hilly Land Interdisciplinary Experimental Station under Chinese Academy of Sciences (CAS), and studied the soil CO2, CH4 and N2O emissions from the plantation under effects of understory removal and Cassia alata addition. The CO2 flux of the plantation maintained at a higher level during rainy season but decreased obviously in dry season, while the CH4 and N2O fluxes varied widely from September to November, with the peaks in October. Under the effects of understory removal and C. alata addition, the soil in the plantation could be a sink or a source of CH4, but consistently a source of CO2 and N2O. Understory removal enhanced the soil CO2 emission (P < 0.05 ), C. alata addition increased the soil CH4 emission (P < 0.05), while both understory removal and C. alata addition increased the soil N2O emission (P < 0.05). Surface soil temperature, moisture content, NO3(-) -N concentration, and microbial biomass carbon were the main factors affecting the soil CO2, CH4 and N2O emissions.

  10. Effects of Tabriz petrochemicals’ biological sludge on heavy metals concentration in soil and spring barley in greenhouse conditions

    Directory of Open Access Journals (Sweden)

    Sh. Oustan

    2012-03-01

    Full Text Available Utilizing sewage sludge as a source of cheap fertilizer and rich in nutrients is common in some parts of Iran. But, too much application causes accumulation of heavy metals in soil, which results in soil pollution and transfer of this pollution to food chain and endangers human and animal health. The aim of this research was to investigate the effect of biological sludge of Tabriz petrochemicals complex on some heavy metals concentration in spring barley grown in a calcareous soil after 6 months of incubation. The experiment was conducted in greenhouse conditions with 5 levels of 0 (control, 25, 50, 75 and 100 ton/ha sewage sludge, in three replications, based on complete randomized blocks design. Soil analysis showed that application of biological sludge significantly increased DTPA extractable Fe, Zn, Mn, Cu and Cd (except 25 ton/ha treatment compared to the control. The results of plant analysis showed an increase of Fe, Zn and Mn in shoots and Zn and Mn in roots, compared to the control. But elevation of root Fe content was not significant. The amount of Cu and Cd in shoots and roots was below the detection limit of the instrument. Overall, it was concluded that although the application of biological sludge increased the content of heavy metals in soil, but its effect on concentration of toxic elements, such as Cd, in plants was not significant.

  11. Effect of Zinc and Manganese Nutrition on Fruit Yield and Nutrient Concentrations in Greenhouse Tomato in Hydroponic Culture

    Directory of Open Access Journals (Sweden)

    A. Tavassoli

    2010-06-01

    Full Text Available Abstract This research was performed in a completely randomized block design with four replications to investigate zinc (Zn and manganese (Mn nutrition effects on greenhouse tomato (Lycopersicon esculentum Mill. cv. HAMRA in a perlite-containing media. Experimental treatments were: (1 control (Mn and Zn-free nutrient solution, (2 application of Mn in a concentration equal to the full Hoagland’s nutrient solution (4.06 mg/l, (3 application of Zn in a concentration equal to the full Hoagland’s nutrient solution (4.42 mg/l, (4 application of Mn and Zn in concentrations equal to the 50% Hoagland’s nutrient solution (2.03 mg/l Mn + 2.21 mg/l Zn, and (5 application of Mn and Zn in concentrations equal to the full Hoagland’s nutrient solution (4.06 mg/l Mn + 4.42 mg/l Zn. Results showed that the highest fresh-fruit yield, fruit and leaf dry matter and content of Mn and Zn in fruit were obtained from single or combined application of Mn and Zn in concentrations equal to the full Hoagland’s nutrient solution. In addition, Zn and Mn nutrition significantly affected the fruit concentrations of crude protein, nitrogen and phosphorus, while the effect of these treatments on fruit size of tomato was not significant.

  12. The effect of greenhouse gas concentrations and ice sheets on the glacial AMOC in a coupled climate model

    Science.gov (United States)

    Klockmann, Marlene; Mikolajewicz, Uwe; Marotzke, Jochem

    2016-09-01

    Simulations with the Max Planck Institute Earth System Model (MPI-ESM) are used to study the sensitivity of the AMOC and the deep-ocean water masses during the Last Glacial Maximum to different sets of forcings. Analysing the individual contributions of the glacial forcings reveals that the ice sheets cause an increase in the overturning strength and a deepening of the North Atlantic Deep Water (NADW) cell, while the low greenhouse gas (GHG) concentrations cause a decrease in overturning strength and a shoaling of the NADW cell. The effect of the orbital configuration is negligible. The effects of the ice sheets and the GHG reduction balance each other in the deep ocean so that no shoaling of the NADW cell is simulated in the full glacial state. Experiments in which different GHG concentrations with linearly decreasing radiative forcing are applied to a setup with glacial ice sheets and orbital configuration show that GHG concentrations below the glacial level are necessary to cause a shoaling of the NADW cell with respect to the pre-industrial state in MPI-ESM. For a pCO2 of 149 ppm, the simulated overturning state and the deep-ocean water masses are in best agreement with the glacial state inferred from proxy data. Sensitivity studies confirm that brine release and shelf convection in the Southern Ocean are key processes for the shoaling of the NADW cell. Shoaling occurs only when Southern Ocean shelf water contributes significantly to the formation of Antarctic Bottom Water.

  13. [Effects of no-tillage and fertilization on paddy soil CH4 and N2O emissions and their greenhouse effect in central China].

    Science.gov (United States)

    Dai, Guang-zhao; Li, Cheng-fang; Cao, Cou-gui; Zhan, Ming; Tong, Le-ga; Mei, Shao-hua; Zhai, Zhong-bing; Fan, Duan-yang

    2009-09-01

    By using static chamber-gas chromatographic techniques, the CH4 and N2O emissions from the paddy soil in southeast Hubei were measured. Four treatments were installed, i.e., no-tillage plus no-fertilization (NT0), conventional tillage plus no-fertilization (CT0), no-tillage plus fertilization (NTC), and conventional tillage plus fertilization (CTC). In all treatments, the CH4 emission had a seasonal variation of increasing first and decreasing then, while the N2O emission had no significant seasonal variation. Fertilization increased the CH4 and N2O emissions significantly. NT0 increased the CH4 emission and decreased the N2O emission significantly, compared with CT0; NTC only decreased the CH4 emission and increased the N2O emission slightly, compared with CTC. The analysis on the integrated greenhouse effect of CH4 and N2O showed that NT0 increased the effect by 25.9%, compared with CT0, while NTC decreased the effect by 10.1%, compared with CTC. Therefore, a reasonable arrangement of fertilization and no-tillage could reduce the integrated greenhouse effect of CH4 and N2O from paddy field.

  14. Inventory of atmospheric pollutant and greenhouse gas emissions in France. Sectoral series and extended analyses - SECTEN Format, April 2011; Inventaire des emissions de polluants atmospheriques et de gaz a effet de serre en France. Series sectorielles et analyses etendues - Format SECTEN, avril 2011

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Jean-Pierre; Fontelle, Jean-Pierre; Serveau, Laetitia; Allemand, Nadine; Jeannot, Coralie; Andre, Jean-Marc; Joya, Romain; Deflorenne, Emmanuel; Martinet, Yann; Druart, Ariane; Mathias, Etienne; Gavel, Antoine; Nicco, Laetitia; Gueguen, Celine; Prouteau, Emilie; Jabot, Julien; Tuddenham, Mark; Jacquier, Guillaume; Vincent, Julien

    2011-04-15

    This report supplies an update of emissions into the atmosphere in mainland France under the SNIEPA in accordance with the 'SECTEN' format defined by CITEPA. This report aims to reconstitute emissions broken down in accordance with the traditional economic sectors such as industry, residential/tertiary sector, agriculture, etc. (cf. Annex 2 for the corresponding links between SECTEN sectors and sub-sectors, and the SNAP nomenclature). Unless otherwise indicated, the results cover the period 1990-2010 (estimations for 2010 are preliminary), but also go back further in time: to 1980 for certain substances covered by the different protocols adopted under the 1979 UNECE Convention on Long-Range Transboundary Air Pollution. For other substances traditionally monitored by CITEPA for many years, the results go back to 1960 (SO{sub 2}, NO{sub x}, CO{sub 2}, CO). Data are presented for 28 different substances in total and various indicators such as those concerning acidification or the greenhouse effect. The report shows that for most substances, emissions have been drastically reduced over the last 10 or 20 years, especially during the period 1990-2009: Very sharp decrease (over 40%) SO{sub 2}, NMVOCs, CO, SF{sub 6}, PFCs in CO{sub 2} equivalent, As, Cd, Cr, Hg, Ni, Pb, Zn, dioxins and furans, PAHs, HCB, PCBs, PM{sub 2.5} and PM{sub 1.0}, Sharp decrease (between 20 and 40%) NO{sub x}, N{sub 2}O, Se, TSP, PM{sub 10} and acid equivalent index, Considerable decrease (between 5 and 20%) NH{sub 3}, CH{sub 4} without LULUCF, CO{sub 2} without LULUCF, Cu and the global warming potential index without LULUCF, Stabilisation (between -5 and +5%) No substance, Very sharp increase (over 40%) HFCs in CO{sub 2} equivalent. For more than 2/3 of substances, emission levels in 2009 were the lowest since records began (1960 to 1990 depending on the substances). For the most part of atmospheric pollutants (except the greenhouse gases), the preliminary estimations for year 2010 look

  15. Metropolitan New York in the greenhouse: Air quality and health effects

    Energy Technology Data Exchange (ETDEWEB)

    Kleinman, L.I.; Lipfert, F.

    1996-01-01

    A variety of potential effects on human health resulting from climate change have been identified in several assessments. According to an international panel{sup 1} they include direct effects of extreme temperatures on cardiovascular deaths, secondary effects due to vector-borne diseases or crop yields, and tertiary effects such as those that might arise from conflicts over freshwater supplies. To this fist we add the secondary effects of increased air pollution, which may result either directly from climate change or indirectly from increased air conditioning loads and the corresponding pollutant emissions from electric utilities. Higher ozone concentrations have been linked to increased ambient temperatures by both theory and observations of monitoring data. A similar association with particulate matter has been limited to observations, thus far. The pollution-heat linkage has been recognized before` but health effects have not been evaluated in terms of predictions of the joint effects of both agents. This paper has been prepared in two sections. First, we discuss the ozone situation with special reference to the Northeast Corridor and New York. In the second section, we present estimates of the health effects of climate change on New York and discuss some mitigation options.

  16. The Effect of Recent Venus Transit on Earths Atmosphere

    OpenAIRE

    H. P. Sardar; Mandal, S. K.; Mandal, P. K.; Guha, A.; Sarkar, S. K.; Sarkar, B. K.; Adhikari, S. K.; De, B. K.; S S; Ray, M.

    2006-01-01

    Some experiments on June 8, 2004, the day of transit of Venus across the Sun, were undertaken at Kolkata (latitude: 23034? N) to observe effect, if any, of transit of Venus on FWF, ELF and VLF amplitudes. The result shows good correlation between their temporal variations during the transit. The observation was unbelievable as the Venus subtends only 1/32th of the cone subtended by Sun on Earth. This anomaly may be explained on the assumption that the height of Venusian atmosphere with high c...

  17. The effect of recent Venus transit on Earths atmosphere

    OpenAIRE

    H. P. Sardar; Mandal, S. K.; Mandal, P. K.; Guha, A.; Sarkar, S. K.; Sarkar, B. K.; Adhikari, S. K.; De, B. K.; S S; Ray, M.

    2006-01-01

    Some experiments on June 8, 2004, the day of transit of Venus across the Sun, were undertaken at Kolkata (latitude: 22°34lN) to observe the effect, if any, of transit of Venus on FWF, ELF and VLF amplitudes. The result shows a good correlation between their temporal variations during the transit. The observation was unbelievable as the Venus subtends only 1/32th of the cone subtended by Sun on Earth. This anomaly may be explained on the assumption that the height of Venusian atmosphere with h...

  18. Climate Change Impacts and Greenhouse Gas Mitigation Effects on U.S. Hydropower Generation

    Science.gov (United States)

    Climate change will have potentially significant effects on hydropower generation due to changes in the magnitude and seasonality of river runoff and increases in reservoir evaporation. These physical impacts will in turn have economic consequences through both producer revenues ...

  19. Greenhouse gas emissions from coastal freshwater wetlands in Veracruz Mexico: Effect of plant community and seasonal dynamics

    Science.gov (United States)

    Marín-Muñiz, José Luis; Hernández, María E.; Moreno-Casasola, Patricia

    2015-04-01

    Wetlands play an important role in modulating atmospheric concentrations of Greenhouse Gases (GHGs), such as methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2). Despite the fact that ∼30% of wetlands in the world occur in tropical latitudes, little is known about GHG emissions from these ecosystems and the variables that control such emissions. We investigated the CH4, N2O and CO2 emissions in tropical freshwater marshes (FM) and swamps (FS) on the coastal plain of Veracruz, Mexico. GHGs were measured every two months using the closed chamber technique from April 2010 to February 2012 (CH4 and N2O) and during the last year for CO2. The ranges of the emissions were 20-2000 mg C-CH4 m-2 d-1, -2-16 mg N-N2O m-2 d-1 and 0.5-18 g C-CO2 m-2d-1. There were not significant differences in the emissions between FM and FS (P = 0.314, 0.528 and 0.213 for CH4, N2O, and CO2, respectively). However, significant differences (P 364 mg m-2 d-1) than during dry season (<150 mg m-2 d-1). The opposite was observed for CO2 emissions, during dry season, wetland soils were more aerobic and CO2 fluxes increased (FM: 11 ± 2, FS: 12 ± 1 g m-2 d-1). N-N2O emissions (FM: 1.5 ± 0.96, FS: 2.4 ± 0.9 mg m-2 d-1) were similar during different climatic season (P = 0.056). Based on the global warming potential, CH4 was the main contributor to total GHGs emission during the rainy and windy seasons (75-93%), while CO2 was predominant during the dry season (79.6%) and N2O contributed with less than 7% in the three seasons. Water level and redox potential were found to be main factors influencing GHG emissions in these wetlands.

  20. The cost effectiveness of a policy to store carbon in Australian agricultural soils to abate greenhouse gas emissions

    Science.gov (United States)

    White, Robert E.; Davidson, Brian

    2015-07-01

    Data for cropping and pastoral enterprises in south eastern Australia were used in a cost-effectiveness analysis to assess the feasibility of abating greenhouse gas (GHG) emissions through storing soil carbon (C) as soil organic matter under the Australian government's Carbon Farming Initiative. We used the C credit value for 2013-14 of 24.15 per tonne of CO2- equivalent (CO2-e) and a C storage rate of 0.5 tonne C/hectare/year for conversion of cropland to pasture. Given that a change of enterprise is driven primarily by farmer returns, we found that none of the changes were feasible at current prices, with the exception of wheat to cattle or sheep in an irrigated system, and dryland cotton to cattle or sheep. Given that our model scenario assumed the most favourable economic factors, it is unlikely that increased soil C storage through a change from cropping to pasture can make a significant contribution to abating Australia's CO2 emissions. However, of greater concern to society is the methane emissions from grazing cattle or sheep, which would negate any gain in soil C under pasture, except for a switch from dryland cropping to sheep.

  1. [Effects of low temperature and weak light on the functions of photosystem in Prunus armeniaca L. leaves in solar greenhouse].

    Science.gov (United States)

    Sun, Shan; Zhang, Li-tao; Wang, Jia-Xi; Wang, Shao-Min; Gao, Hua-Jun; Gao, Hui-Yuan

    2008-03-01

    In this paper, the net photosynthetic rate (Pn), actual photochemical efficiency of PS II (PhiPSII), photochemical quenching (qp), and maximal photochemical efficiency of PS II in light (Fv'/Fm') of apricot (Prunus armeniaca) leaves in solar greenhouse were measured, and the effects of low temperature (7 degrees C) and weak light (200 micromol x m(-2) x s(-1) PFD) on the photoinhibition of PS I and PS II were investigated. The results showed that the optimal temperature for the photosynthesis of apricot leaves was around 25 degrees C, and the photosynthetic capacity was reduced greatly by the low temperature and weak light, inducing a markedly increased excitation press (1-qp) and in turn, resulting in photoinhibition. The functions of both PS I and PS II were damaged by the low temperature and weak light. Comparing with those only subjected to low temperature, the leaves subjected to both low temperature and weak light had a decreased activity of PS I, with a decrement of 28.26% within 2 h, but their maximal photochemical effeciency of PS II (Fv/Fm) had little change in the same period, suggesting that under low temperature and weak light, PS I was more suffered from photoinhibition than PS II.

  2. [Effects of soil covering on solar greenhouse pepper water use efficiency and soil nitrate N and available phosphorus contents].

    Science.gov (United States)

    Zhou, Mao-juan; Liang, Yin-li; Chen, Jia-rui; Xiong, Ya-mei; Wei, Ze-xiu

    2007-06-01

    A greenhouse study on the effects of soil covering on pepper (Capsicum anmuum L.) water use efficiency and soil nitrate and available phosphorus contents showed that straw mulch + plastic film mulch could get the highest pepper yield water use efficiency (33.04 kg . m(-3)) and economic water use efficiency (50.22 yuan . m(-3)), followed by plastic film mulch, with the two parameters being 18.81 kg . m(-3) and 28.57 yuan . m(-3), respectively. Significant differences of nitrate N content in 0-20 cm soil layer were observed among different treatments. The control had the highest nitrate N content (50.33 mg . kg(-1)), followed by straw mulch (31.98 mg . kg(-1)) and straw + plastic film mulch (31.96 mg . kg(-1)), and plastic film mulch and applying water preserving agent. Compared with the control, soil covering could increase the nitrate N use efficiency of pepper, and decrease the accumulation of nitrate N in plough layer. In 0-20 cm soil layer, treatment plastic film mulch had the lowest available phosphorus content (0.72 mg . kg(-3)), and the second (0. 92 mg . kg(-1)) was the treatment straw + plastic film mulch. Treatments straw + plastic film mulch and plastic film mulch could increase pepper fruit yield and fertilizer use efficiency, and decrease fertilizer loss.

  3. Transportation Energy Futures Series. Effects of the Built Environment on Transportation. Energy Use, Greenhouse Gas Emissions, and Other Factors

    Energy Technology Data Exchange (ETDEWEB)

    Porter, C. D. [National Renewable Energy Lab. (NREL) and Cambridge Systematics, Inc., Golden, CO (United States); Brown, A. [National Renewable Energy Lab. (NREL) and Cambridge Systematics, Inc., Golden, CO (United States); Dunphy, R. T. [National Renewable Energy Lab. (NREL) and Cambridge Systematics, Inc., Golden, CO (United States); Vimmerstedt, L. [National Renewable Energy Lab. (NREL) and Cambridge Systematics, Inc., Golden, CO (United States)

    2013-03-15

    Planning initiatives in many regions and communities aim to reduce transportation energy use, decrease emissions, and achieve related environmental benefits by changing land use. This report reviews and summarizes findings from existing literature on the relationship between the built environment and transportation energy use and greenhouse gas emissions, identifying results trends as well as potential future actions. The indirect influence of federal transportation and housing policies, as well as the direct impact of municipal regulation on land use are examined for their effect on transportation patterns and energy use. Special attention is given to the 'four D' factors of density, diversity, design and accessibility. The report concludes that policy-driven changes to the built environment could reduce transportation energy and GHG emissions from less than 1% to as much as 10% by 2050, the equivalent of 16%-18% of present-day urban light-duty-vehicle travel. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

  4. Transportation Energy Futures Series: Effects of the Built Environment on Transportation: Energy Use, Greenhouse Gas Emissions, and Other Factors

    Energy Technology Data Exchange (ETDEWEB)

    Porter, C. D.; Brown, A.; Dunphy, R. T.; Vimmerstedt, L.

    2013-03-01

    Planning initiatives in many regions and communities aim to reduce transportation energy use, decrease emissions, and achieve related environmental benefits by changing land use. This report reviews and summarizes findings from existing literature on the relationship between the built environment and transportation energy use and greenhouse gas emissions, identifying results trends as well as potential future actions. The indirect influence of federal transportation and housing policies, as well as the direct impact of municipal regulation on land use are examined for their effect on transportation patterns and energy use. Special attention is given to the 'four D' factors of density, diversity, design and accessibility. The report concludes that policy-driven changes to the built environment could reduce transportation energy and GHG emissions from less than 1% to as much as 10% by 2050, the equivalent of 16%-18% of present-day urban light-duty-vehicle travel. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

  5. Effects of ethanol on vehicle energy efficiency and implications on ethanol life-cycle greenhouse gas analysis.

    Science.gov (United States)

    Yan, Xiaoyu; Inderwildi, Oliver R; King, David A; Boies, Adam M

    2013-06-01

    Bioethanol is the world's largest-produced alternative to petroleum-derived transportation fuels due to its compatibility within existing spark-ignition engines and its relatively mature production technology. Despite its success, questions remain over the greenhouse gas (GHG) implications of fuel ethanol use with many studies showing significant impacts of differences in land use, feedstock, and refinery operation. While most efforts to quantify life-cycle GHG impacts have focused on the production stage, a few recent studies have acknowledged the effect of ethanol on engine performance and incorporated these effects into the fuel life cycle. These studies have broadly asserted that vehicle efficiency increases with ethanol use to justify reducing the GHG impact of ethanol. These results seem to conflict with the general notion that ethanol decreases the fuel efficiency (or increases the fuel consumption) of vehicles due to the lower volumetric energy content of ethanol when compared to gasoline. Here we argue that due to the increased emphasis on alternative fuels with drastically differing energy densities, vehicle efficiency should be evaluated based on energy rather than volume. When done so, we show that efficiency of existing vehicles can be affected by ethanol content, but these impacts can serve to have both positive and negative effects and are highly uncertain (ranging from -15% to +24%). As a result, uncertainties in the net GHG effect of ethanol, particularly when used in a low-level blend with gasoline, are considerably larger than previously estimated (standard deviations increase by >10% and >200% when used in high and low blends, respectively). Technical options exist to improve vehicle efficiency through smarter use of ethanol though changes to the vehicle fleets and fuel infrastructure would be required. Future biofuel policies should promote synergies between the vehicle and fuel industries in order to maximize the society-wise benefits or

  6. Cost-effective policy instruments for greenhouse gas emission reduction and fossil fuel substitution through bioenergy production in Austria

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Johannes, E-mail: johannes.schmidt@boku.ac.at [Institute for Sustainable Economic Development, University of Natural Resources and Life Sciences, Peter Jordan Strasse 82, A-1190 Vienna (Austria); Leduc, Sylvain [International Institute for Applied Systems Analysis, Schlossplatz 1, A-2361 Laxenburg (Austria); Dotzauer, Erik [Maelardalen University, P.O. Box 883, SE-72123 Vaesteras (Sweden); Schmid, Erwin [Institute for Sustainable Economic Development, University of Natural Resources and Life Sciences, Peter Jordan Strasse 82, A-1190 Vienna (Austria)

    2011-06-15

    Climate change mitigation and security of energy supply are important targets of Austrian energy policy. Bioenergy production based on resources from agriculture and forestry is an important option for attaining these targets. To increase the share of bioenergy in the energy supply, supporting policy instruments are necessary. The cost-effectiveness of these instruments in attaining policy targets depends on the availability of bioenergy technologies. Advanced technologies such as second-generation biofuels, biomass gasification for power production, and bioenergy with carbon capture and storage (BECCS) will likely change the performance of policy instruments. This article assesses the cost-effectiveness of energy policy instruments, considering new bioenergy technologies for the year 2030, with respect to greenhouse gas emission (GHG) reduction and fossil fuel substitution. Instruments that directly subsidize bioenergy are compared with instruments that aim at reducing GHG emissions. A spatially explicit modeling approach is used to account for biomass supply and energy distribution costs in Austria. Results indicate that a carbon tax performs cost-effectively with respect to both policy targets if BECCS is not available. However, the availability of BECCS creates a trade-off between GHG emission reduction and fossil fuel substitution. Biofuel blending obligations are costly in terms of attaining the policy targets. - Highlights: > Costs of energy policies and effects on reduction of CO{sub 2} emissions and fossil fuel consumption. > Particular focus on new bioenergy production technologies such as second generation biofuels. > Spatially explicit techno-economic optimization model. > CO{sub 2} tax: high costs for reducing fossil fuel consumption if carbon capture and storage is available. > Biofuel policy: no significant reductions in CO{sub 2} emissions or fossil fuel consumption.

  7. Mechanisms of impact of greenhouse gases on the Earth's ozone layer in the Polar Regions

    Science.gov (United States)

    Zadorozhny, Alexander; Dyominov, Igor

    A numerical 2-D zonally averaged interactive dynamical radiative-photochemical model of the atmosphere including aerosol physics is used to examine the impact of the greenhouse gases CO2, CH4, and N2O on the future long-term changes of the Earth's ozone layer, in particular on its expected recovery after reduction of anthropogenic discharges of chlorine and bromine compounds into the atmosphere. The model allows calculating self-consistently diabatic circu-lation, temperature, gaseous composition of the troposphere and stratosphere at latitudes from the North to South Poles, as well as distribution of sulphate aerosol particles and polar strato-spheric clouds (PSCs) of types I and II. The scenarios of expected changes of the anthropogenic pollutants for the period from 1980 through 2050 are taken from Climate Change 2001. The processes, which determine the influence of anthropogenic growth of atmospheric abun-dance of the greenhouse gases on the long-term changes of the Earth's ozone layer in the Polar Regions, have been studied in details. Expected cooling of the stratosphere caused by increases of greenhouse gases, most importantly CO2, essentially influences the ozone layer by two ways: through temperature dependencies of the gas phase reaction rates and through enhancement of polar ozone depletion via increased PSC formation. The model calculations show that a weak-ness in efficiencies of all gas phase catalytic cycles of the ozone destruction due to cooling of the stratosphere is a dominant mechanism of the impact of the greenhouse gases on the ozone layer in Antarctic as well as at the lower latitudes. This mechanism leads to a significant acceleration of the ozone layer recovery here because of the greenhouse gases growth. On the contrary, the mechanism of the impact of the greenhouse gases on the ozone through PSC modification be-gins to be more effective in Arctic in comparison with the gas phase mechanism in springs after about 2020, which leads to retard

  8. Radiative forcings for 28 potential Archean greenhouse gases

    CERN Document Server

    Byrne, Brendan

    2014-01-01

    Despite reduced insolation in the late Archean, evidence suggests a warm climate which was likely sustained by a stronger greenhouse effect, the so-called Faint Young Sun Problem (FYSP). CO2 and CH4 are generally thought to be the mainstays of this enhanced greenhouse, though many other gases have been proposed. We present high accuracy radiative forcings for CO2, CH4 and 26 other gases, performing the radiative transfer calculations at line-by-line resolution and using HITRAN 2012 line data for background pressures of 0.5, 1, and 2 bar of atmospheric N2. For CO2 to resolve the FYSP alone at 2.8 Gyr BP (80% of present solar luminosity), 0.32 bar is needed with 0.5 bar of atmospheric N2, 0.20 bar with 1 bar of atmospheric N2, or 0.11 bar with 2 bar of atmospheric N2. For CH4, we find that near-infrared absorption is much stronger than previously thought, arising from updates to the HITRAN database. CH4 radiative forcing peaks at 10.3, 9, or 8.3 Wm-2 for background pressures of 0.5, 1 or 2 bar, likely limiting ...

  9. Climate Change Impacts and Greenhouse Gas Mitigation Effects on US Water Quality

    Science.gov (United States)

    Climate change will have potentially significant effects on freshwater quality due to increases in river and lake temperatures, changes in the magnitude and seasonality of river runoff, and more frequent and severe extreme events. These physical impacts will in turn have economic...

  10. Organic versus conventional fertilization effects on sweet basil (Ocimum basilicum L.) growth in a greenhouse system

    Science.gov (United States)

    Ocimum basilicum L. (sweet basil) is an essential oil producing crop used in culinary and fragrance applications. The objective of this controlled environment study was to evaluate the effects of organic and conventional fertilization, (applied at two nitrogen rates, 150 and 250 kg N/ha), on plant g...

  11. Effect of the Evaporative Cooling on the Human Thermal Comfort and Heat Stress in a Greenhouse under Arid Conditions

    Directory of Open Access Journals (Sweden)

    A. M. Abdel-Ghany

    2013-01-01

    Full Text Available Thermal sensation and heat stress were evaluated in a plastic greenhouse, with and without evaporative cooling, under arid climatic conditions in Riyadh, Saudi Arabia. Suitable thermal comfort and heat stress scales were selected for the evaluation. Experiments were conducted in hot sunny days to measure the required parameters (i.e., the dry and wet bulb temperatures, globe temperature, natural wet bulb temperature, and solar radiation flux in the greenhouse. The results showed that in the uncooled greenhouse, workers are exposed to strong heat stress and would feel very hot most of the day time; they are safe from heat stress risk and would feel comfortable during night. An efficient evaporative cooling is necessary during the day to reduce heat stress and to improve the comfort conditions and is not necessary at night. In the cooled greenhouse, workers can do any activity: except at around noon they should follow a proposed working schedule, in which the different types of work were scheduled along the daytimes based on the heat stress value. To avoid heat stress and to provide comfort conditions in the greenhouses, the optimum ranges of relative humidity and air temperature are 48–55% and 24–28°C, respectively.

  12. Effects of Soil Depth and Season Variation on Community Structure of Arbuscular Mycorrhizal Fungi in Greenhouse Soils Planted with Watermelon

    Institute of Scientific and Technical Information of China (English)

    LIU Run-Jin; LI Yan; DIAO Zhi-Kai; LI Min; LIN Xian-Gui

    2013-01-01

    The characteristics of arbuscular mycorrhizal fungal (AMF) community structure in various soil depths and growing seasons of watermelon (Citrullus vulgaris) grown in commercial greenhouses in Daxing of Beijing and Weifang and Laiyang of Shandong,China were investigated using both morphological identification and denaturing gradient gel electrophoresis.The sampled soils had been used for continuous greenhouse production of watermelon for 0,5,10,15,or 20 years.Glomus claroideum was the dominant species in the greenhouse soils planted for 5,10,and 15 years in Laiyang,while Glomus mosseae and Glomus etunicatum were dominant in the nearby open farmland soil.Sorenson's similarity index of AMF community composition ranged from 0.67 to 0.84 in the soils planted for 5 years,and from 0.29 to 0.33 for 20 years among the three locations.Spore abundance,species richness,and the Shannon index were highest near the soil surface (0-10 cm) and decreased with soil depth,and higher in June and October than in August and December.Canonical correspondence analysis showed that available P and the number of years that soil had been used for greenhouse production were the main factors contributing to the variance of AMF community composition.It was concluded that the community structure of AMF was mainly influenced by soil available P and planting time of watermelon as well as by soil depth and seasonal variation in the commercial greenhouse.

  13. The effect of atmospheric pollution on building materials

    Science.gov (United States)

    Grossi, C. M.; Brimblecombe, P.

    2002-11-01

    This chapter surveys main effects of atmospheric pollution on building materials. It summarises these effects on stone, bricks, mortar, concrete, glass, metals (iron, zinc, copper, bronze, aluminium, lead and silver), polymers, paints and timber. Special attention is paid to stone because of its extensive use as building material in the cultural heritage. In general, main damaging agent is sulfur dioxide which leads to sulfation of many materials, particularly carbonate-bearing stones. However, the decline of sulfur dioxide in cities means that the recognition of the prime role of this pollutant presents something of a dilemma. It is increasingly necessary to consider other substances that can contribute to material decay e.g. nitrogen oxides, chlorides and ozone, either acting as synergistic to the sulfation reaction or as main decay agents, such as the case of aluminium and polymers. Particulate matter often from diesel vehicles can also accelerate the oxidation of SO2 on the surface (traditionally sulfur dioxide with Fe-rich particles) and blacken the materials surface in the case of soot. These processes contribute to the formation of black-crusts when embedded in the gypsum layer resulting from the material sulfation, but again the rate in the modem atmosphere is a matter of much research.

  14. Geodetic refraction effects of electromagnetic wave propagation through the atmosphere

    CERN Document Server

    1984-01-01

    With very few exceptions, geodetic measurements use electro­ magnetic radiation in order to measure directions, distances, time delays, and Doppler frequency shifts, to name the main ter­ restrial and space observables. Depending on the wavelength of the radiation and the purpose of the measurements, the follow­ ing parameters of the electromagnetic wave are measured: ampli­ tude, phase, angle-of-arrival, polarisation and frequency. Ac­ curate corrections have to be applied to the measurements in order to take into account the effects of the intervening medium between transmitter and receiver. The known solutions use at­ mospheric models, special observation programs, remote sensing techniques and instrumental methods. It has been shown that the effects of the earth's atmospheric envelope present a fundamental limitation to the accuracy and precision of geodetic measurements. This applies equally to ter­ restrial and space applications. Instrumental accuracies are al­ ready below the atmospherically i...

  15. Solar particle effects on minor components of the Polar atmosphere

    Directory of Open Access Journals (Sweden)

    A. Damiani

    2008-02-01

    Full Text Available Solar activity can influence the Earth's environment, and in particular the ozone layer, by direct modulation of the e.m. radiation or through variability of the incoming cosmic ray flux (solar and galactic particles. In particular, solar energetic particles (SEPs provide additional external energy to the terrestrial environment; they are able to interact with the minor constituents of the atmospheric layer and produce ionizations, dissociations, dissociative ionizations and excitations. This paper highlights the SEP effects on the chemistry of the upper atmosphere by analysing some SEP events recorded during 2005 in the descending phase of the current solar cycle. It is shown that these events can lead to short- (hours and medium- (days term ozone variations through catalytic cycles (e.g. HOx and NOx increases. We focus attention on the relationship between ozone and OH data (retrieved from MLS EOS AURA for four SEP events: 17 and 20 January, 15 May and 8 September. We confirm that SEP effects are different on the night and day hemispheres at high latitudes.

  16. Solar particle effects on minor components of the Polar atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Damiani, A. [ICES - International Center for Earth Sciences c/o Consiglio Nazionale delle Ricerche, Rome (Italy). Ist. di Acustica ' O.M. Corbino' ; INAF, Roma (Italy). Ist. di Fisica dello Spazio Interplanetario; Storini, M.; Laurenza, M. [INAF, Roma (Italy). Ist. di Fisica dello Spazio Interplanetario; Rafanelli, C. [ICES - International Center for Earth Sciences c/o Consiglio Nazionale delle Ricerche, Rome (Italy). Ist. di Acustica ' O.M. Corbino'

    2008-07-01

    Solar activity can influence the Earth's environment, and in particular the ozone layer, by direct modulation of the e.m. radiation or through variability of the incoming cosmic ray flux (solar and galactic particles). In particular, solar energetic particles (SEPs) provide additional external energy to the terrestrial environment; they are able to interact with the minor constituents of the atmospheric layer and produce ionizations, dissociations, dissociative ionizations and excitations. This paper highlights the SEP effects on the chemistry of the upper atmosphere by analysing some SEP events recorded during 2005 in the descending phase of the current solar cycle. It is shown that these events can lead to short- (hours) and medium- (days) term ozone variations through catalytic cycles (e.g. HO{sub x} and NO{sub x} increases). We focus attention on the relationship between ozone and OH data (retrieved from MLS EOS AURA) for four SEP events: 17 and 20 January, 15 May and 8 September. We confirm that SEP effects are different on the night and day hemispheres at high latitudes. (orig.)

  17. Effect of Alum Additions to Poultry Litter on In-House Ammonia and Greenhouse Gas Concentrations and Emissions.

    Science.gov (United States)

    Eugene, Branly; Moore, Philip A; Li, Hong; Miles, Dana; Trabue, Steven; Burns, Robert; Buser, Michael

    2015-09-01

    Alum [Al(SO4) ·14HO] addition to poultry litter has been shown to reduce ammonia (NH) concentrations in poultry houses; however, its effects on greenhouse gas (GHG; NO, CH, and CO) emissions is unknown. The objectives of this study were to determine the effects of alum additions on (i) in-house NH and GHG concentrations, (ii) NH and GHG emissions, and (iii) litter chemical properties. Two identical broiler houses located in northwest Arkansas were used for this study: one house was a control and the other was treated with alum between each flock of birds. Ventilation rates were coupled with in-house NH and GHG measurements to determine emission rates. Overall, alum additions significantly reduced the daily average in-house NH concentration by 42% (8.9 vs. 15.4 μL L), and the overall NH emission rate was reduced by 47% (7.2 vs. 13.4 kg d house). The average cumulative NH emission for the three flocks was 330 kg house flock for the alum-treated house and 617 kg house flock for the control. Concentrations and emissions of nitrous oxide (NO) and methane (CH) from the alum-treated house were not significantly different than the untreated house. However, carbon dioxide (CO) emissions were significantly higher from the untreated house than the alum-treated house. Alum also significantly increased litter N content and reduced the C/N ratio. These results indicate that the addition of alum to poultry litter is not only an effective management practice for reducing in-house NH concentrations and emissions but also significantly reduces CO emissions from poultry facilities.

  18. Radiative forcing due to greenhouse gas emission and sink histories in Finland and its future control potential

    Energy Technology Data Exchange (ETDEWEB)

    Savolainen, I.; Sinisalo, J.; Pipatti, R. [VTT Energy, Espoo (Finland)

    1995-12-31

    The effective atmospheric lifetimes of the greenhouse gases like carbon dioxide (CO{sub 2}),nitrous oxide (N{sub 2}O) and many of the CFCs are of the order of 100 years. Human activities, as an example GDP, very often change at rates of a few per cents per year,corresponding time constants of some tens of years. Also the forest ecosystems have time constants of this order. Even the human population of the globe is increasing by about two percent per year. Because so many natural and human-linked processes, which are relevant to global warming, have slow change rates of about same order, a time-dependent consideration of the greenhouse warming and its control can give useful information for the understanding of the problem. The objective of the work is to study the anthropogenic greenhouse gas emissions and sinks in Finland and their greenhouse impact as a function of time. The greenhouse impact is expressed in terms of radiative forcing which describes the perturbation in the Earth`s radiation budget. Radiative forcing allows a comparison of the impact of various greenhouse gases and their possible control options as a function of time. The idea behind the calculations is that Finland should in some way steer its share of the global radiative forcing and greenhouse effect. This presentation describes the calculation model REFUGE and the projects in which it has been used

  19. Emissions of greenhouse gases in the United States, 1985--1990

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-10

    The Earth`s capacity to support life depends on the moderating influences of gases that envelop the planet and warm its surface and protect it from harmful radiation. These gases are referred to as ``greenhouse gases.`` Their warming capacity, called ``the greenhouse effect,`` is essential to maintaining a climate hospitable to all plant, animal, and human life. In recent years, however, there has been increasing concern that human activity may be affecting the intricate balance between the Earth`s absorption of heat from the sun and its capacity to reradiate excess heat back into space. Emissions of greenhouse gases from human activities may be an important mechanism that affects global climate. Thus, research is intensifying to improve our understanding of the role human activities might play in influencing atmospheric concentrations of greenhouse gases. On the basis of scientific findings of the past few decades, the US Government and the international community at large are now taking steps toward stabilizing greenhouse gas emissions. This report contributes to that process. Mandated by Congress this report provides estimates of US emissions of the principal greenhouse gases--carbon dioxide, methane, nitrous oxide, chlorofluorcarbons, carbon monoxide, nitrogen oxides, and nonmethane volatile organic compounds. Estimates are for the period 1985 to 1990. Preliminary estimates for 1991 have also been included, whenever data were available.

  20. Integrated Assessment of Ecosystem Effects of Atmospheric Deposition

    Science.gov (United States)

    Ecosystems obtain a portion of their nutrients from the atmosphere. Following the Industrial Revolution, however, human activities have accelerated biogeochemical cycles, greatly enhancing the transport of substances among the atmosphere, water, soil, and living things. The atmos...