WorldWideScience

Sample records for global radiation balance

  1. Radiation losses and global power balance of JT-60 plasmas

    Nishitani, T.; Itami, K.; Nagashima, K.; Tsuji, S.; Hosogane, N.; Yoshida, H.; Ando, T.; Kubo, H.; Takeuchi, H.

    1990-01-01

    The radiation losses and the global power balance for Ohmic and neutral beam heated plasmas have been investigated in different JT-60 configurations. Discharges with a TiC coated molybdenum wall and with a graphite wall, with limiter, outer and lower X-point configurations have been studied by bolometric measurements, thermocouples and an infrared TV camera. In neutral beam heated outer X-point discharges with a TiC coated molybdenum first wall, the radiation loss of the main plasma was very low (10% of the absorbed power). The radiation loss due to oxygen was dominant in this case. On the contrary, in discharges with TiC coated molybdenum limiters the radiation loss was very high (>60% of the absorbed power). In the discharges with a graphite wall the radiated power from the main plasma was 20-25% for both limiter and lower X-point configurations. In lower X-point discharges the main contributor to the radiation loss was oxygen, whereas in limiter discharges the loss due to carbon was equal to the loss due to oxygen. The radiation loss from the lower X-point divertor increased with increasing electron density of the main plasma. (author). 33 refs, 14 figs, 1 tab

  2. EDITORIAL: The Earth radiation balance as driver of the global hydrological cycle

    Wild, Martin; Liepert, Beate

    2010-06-01

    Variations in the intensity of the global hydrological cycle can have far-reaching effects on living conditions on our planet. While climate change discussions often revolve around possible consequences of future temperature changes, the adaptation to changes in the hydrological cycle may pose a bigger challenge to societies and ecosystems. Floods and droughts are already today amongst the most damaging natural hazards, with floods being globally the most significant disaster type in terms of loss of human life (Jonkman 2005). From an economic perspective, changes in the hydrological cycle can impose great pressures and damages on a variety of industrial sectors, such as water management, urban planning, agricultural production and tourism. Despite their obvious environmental and societal importance, our understanding of the causes and magnitude of the variations of the hydrological cycle is still unsatisfactory (e.g., Ramanathan et al 2001, Ohmura and Wild 2002, Allen and Ingram 2002, Allan 2007, Wild et al 2008, Liepert and Previdi 2009). The link between radiation balance and hydrological cycle Globally, precipitation can be approximated by surface evaporation, since the variability of the atmospheric moisture storage is negligible. This is the case because the fluxes are an order of magnitude larger than the atmospheric storage (423 x 1012 m3 year-1 versus 13 x 1012 m3 according to Baumgartner and Reichel (1975)), the latter being determined by temperature (Clausius-Clapeyron). Hence the residence time of evaporated water in the atmosphere is not more than a few days, before it condenses and falls back to Earth in the form of precipitation. Any change in the globally averaged surface evaporation therefore implies an equivalent change in precipitation, and thus in the intensity of the global hydrological cycle. The process of evaporation requires energy, which it obtains from the surface radiation balance (also known as surface net radiation), composed of the

  3. Radiation losses and global energy balance for Ohmically heated discharges in ASDEX

    Mueller, E.R.; Behringer, K.; Niedermeyer, H.

    1982-01-01

    Global energy balance, radiation profiles and dominant impurity radiation sources are compared for Ohmically heated limiter and divertor discharges in the ASDEX tokamak. In discharges with a poloidal stainless-steel limiter, total radiation from the plasma is the dominant energy loss channel. The axisymmetric divertor reduces this volume-integrated radiation to 30-35% of the heating power and additional Ti-gettering halves it again to 10-15%. Local radiation losses in the plasma centre, which are mainly due to the presence of iron impurity ions, are reduced by about one order of magnitude. In high-current (Isub(p) = 400 kA) and high-density (nsub(e)-bar = 6 x 10 13 cm -3 ) ungettered divertor discharges, up to 55% of the heating power is dumped into a cold-gas target inside the divertor chambers. The bolometrically detected volume power losses in the chambers can mainly be attributed to neutral hydrogen atoms with kinetic energies of a few eV. In this parameter range, the divertor plasma is dominated by inelastic molecular and atomic processes, the main process being Franck-Condon dissociation of H 2 molecules. (author)

  4. Radiation loss and global energy balance of ohmically heated divertor discharge in JT-60 tokamak

    Koide, Yoshihiko; Yamada, Kimio; Yoshida, Hidetoshi; Nakamura, Hiroo; Niikura, Setsuo; Tsuji, Shunji

    1986-03-01

    Divertor experiment in JT-60 with a small divertor chamber has been successfully performed up to 1.6 MA discharge. Several divertor effects were experimentally confirmed as follows. Radiation loss in main plasma saturates with the increase of plasma current and its ratio to the input power is about 20 % at 1.5 MA. The rest of input power is exhausted into the divertor chamber and a half of it is dissipated as the radiation loss. Impurity accumulation is not observed during a few sec without internal MHD activity and gross impurity confinement time is several hundred msec. (author)

  5. Radiation: Balancing the record

    Mann, C.C.

    1994-01-01

    This article reviews the radioactivity experiments performed on humans during the cold war, and examines the ethics of the experiments. The radiation experiments can be broadly classified into three groups: researchers knowingly inflicted potential harm, using methods questionable even by the then-current standards; the investigations involved good work by any standards with appropriate safeguards taken; and a third group which falls between the other two, the experiments provided useful information but had ethical flaws. The article also examines the experiments in the light of changing knowledge and moral standards

  6. Analysis of the temporal variation of radiation balance components in arid rice (Oryza sativa L.) culture

    Prates, J.E.; Coelho, D.T.; Steinmetz, S.

    1988-01-01

    The time variation of measured radiation balance components in a cultived rice area (Oryza sativa L.) under arid conditions in the Brazil central-west region was analysed. The relation between global solar radiation, radiation balance, reflected radiation and terrestrial effective radiation in three different stages of the culture development: vegetative stage; blooming and maturation, was determined. (M.C.K.) [pt

  7. Global Sales Training's Balancing Act

    Boehle, Sarah

    2010-01-01

    A one-size-fits-all global sales strategy that fails to take into account the cultural, regulatory, geographic, and economic differences that exist across borders is a blueprint for failure. For training organizations tasked with educating globally dispersed sales forces, the challenge is adapting to these differences while simultaneously…

  8. Global Leadership is a Balancing Act

    Guthey, Eric

    2013-01-01

    Global leadership is not a "state of being" or achievement, but rather a continuous process of achieving balance between control and empowerment on the one hand, and between global and local priorities on the other - all in the face of an increasing number of complexities, constituencies...

  9. Solar energy and global heat balance of a city

    Roulet, Claude-Alain [Ecole Polytechnique Federale, Lab. d' Energie Solaire et de Physique du Batiment, Lausanne (Switzerland)

    2001-07-01

    The global energy balance of a city involves numerous energy flows and is rather complex. It includes, among others, the absorbed solar radiation and the energy fuels on one hand, and the heat loss to the environment --- by radiation, convection and evaporation --- on the other hand. This balance generally results in a temperature in the town that is slightly higher than in the surrounding country. Using solar energy saves imported fuels on one hand, but increases the absorption of solar radiation on the other hand. Simple, steady state models are used to assess the change of heat released to the environment when replacing the use of classical fuels by solar powered plants, on both the global and city scale. The conclusion is that, in most cases, this will reduce the heat released to the environment. The exception is cooling, for which a good solar alternative does not exist today. (Author)

  10. Radiation balances and the solar constant

    Crommelynck, D.

    1981-01-01

    The radiometric concepts are defined in order to consider various types of radiation balances and relate them to the diabetic form of the energy balance. Variability in space and time of the components of the radiation field are presented. A specific concept for sweeping which is tailored to the requirements is proposed. Finally, after establishing the truncated character of the present knowledge of the radiation balance. The results of the last observations of the solar constant are given. Ground and satellite measurement techniques are discussed.

  11. Global Health in Radiation Oncology

    Rodin, Danielle; Yap, Mei Ling; Grover, Surbhi

    2017-01-01

    programs. However, formalized training and career promotion tracks in global health within radiation oncology have been slow to emerge, thereby limiting the sustained involvement of students and faculty, and restricting opportunities for leadership in this space. We examine here potential structures...... and benefits of formalized global health training in radiation oncology. We explore how defining specific competencies in this area can help trainees and practitioners integrate their activities in global health within their existing roles as clinicians, educators, or scientists. This would also help create...... and funding models might be used to further develop and expand radiation oncology services globally....

  12. Energy balance in processes of transition radiation

    Vladimirov, S.V.; Tsytovich, V.N.

    1985-01-01

    The authors consider the transition radiation arising when a charged particle crosses an interface between two nonabsorbing media. It is shown that energy balance is observed under these circumstances. The fulfillment of energy balance in transition radiation for nonabsorbing media is rigorously demonstrated. This allows one to find the energy of the transition radiation from the change in the energy of the intrinsic field of the charge and the work of forces for volume waves, which in a number of cases of complicated configurations may prove to be considerably simpler than a direct calculation of the radiation power. For surface waves, a calculation of the work of forces enables one to determine the radiation power directly

  13. Clouds and the earth's radiation balance

    Schmetz, J; Raschke, E

    1986-01-01

    Cloud formation mechanisms and cloud effects must be known for all regions of the earth for two important purposes of weather and climate research: First, the circulation characteristics of the atmosphere can be defined and understood only if the energy transfer between the atmosphere and the earth's surface is known; secondly, the energy transfer calculations should be as realistic as possible. The article discusses the influence of clouds on the radiation balance of the earth/atmosphere radiation balance, and the effects on weather and climate.

  14. Global aspects of radiation memory

    Winicour, J

    2014-01-01

    Gravitational radiation has a memory effect represented by a net change in the relative positions of test particles. Both the linear and nonlinear sources proposed for this radiation memory are of the ‘electric’ type, or E mode, as characterized by the even parity of the polarization pattern. Although ‘magnetic’ type, or B mode, radiation memory is mathematically possible, no physically realistic source has been identified. There is an electromagnetic counterpart to radiation memory in which the velocity of charged test particles obtain a net ‘kick’. Again, the physically realistic sources of electromagnetic radiation memory that have been identified are of the electric type. In this paper, a global null cone description of the electromagnetic field is applied to establish the non-existence of B-mode radiation memory and the non-existence of E-mode radiation memory due to a bound charge distribution. (paper)

  15. Globalization and the Brazilian balance accounts

    Urbina, Ligia M. Soto; Cabral, Arnoldo S.; Vieira, Wilson J.

    1999-01-01

    The globalization of the world economy calls for a country specialization with new structures for the product sectors and an increase in the competitiveness in areas of specialization. This process requires the amplification of markets and the adoption of technological innovations which increase the volume of economic trade, but also change trade relations. This process is made possible because of price stabilization and the stability and transparency of the exchange rate policy of various countries. In this work it is shown the opportunity to place nuclear energy as one of the sectors in which Brazil may have competitive advantages and enhance its external balance accounts, by the competitive substitution of imports by producing internally goods and services which technology is known by Brazilian firms and because of the increase in exports. (author)

  16. Explicit validation of a surface shortwave radiation balance model over snow-covered complex terrain

    Helbig, N.; Löwe, H.; Mayer, B.; Lehning, M.

    2010-09-01

    A model that computes the surface radiation balance for all sky conditions in complex terrain is presented. The spatial distribution of direct and diffuse sky radiation is determined from observations of incident global radiation, air temperature, and relative humidity at a single measurement location. Incident radiation under cloudless sky is spatially derived from a parameterization of the atmospheric transmittance. Direct and diffuse sky radiation for all sky conditions are obtained by decomposing the measured global radiation value. Spatial incident radiation values under all atmospheric conditions are computed by adjusting the spatial radiation values obtained from the parametric model with the radiation components obtained from the decomposition model at the measurement site. Topographic influences such as shading are accounted for. The radiosity approach is used to compute anisotropic terrain reflected radiation. Validations of the shortwave radiation balance model are presented in detail for a day with cloudless sky. For a day with overcast sky a first validation is presented. Validation of a section of the horizon line as well as of individual radiation components is performed with high-quality measurements. A new measurement setup was designed to determine terrain reflected radiation. There is good agreement between the measurements and the modeled terrain reflected radiation values as well as with incident radiation values. A comparison of the model with a fully three-dimensional radiative transfer Monte Carlo model is presented. That validation reveals a good agreement between modeled radiation values.

  17. Global environment and radiation exposure

    Okamoto, Kazuto

    1991-01-01

    The present status of investigation of acid rain, stratospheric ozone depletion and greenhouse effect and their relations to radiation exposure are reported. Soil acidification increases transfer rates of radioactivities to plants which increases the population dose. There are two types of ozone depletion, conventional type and ozone hole type and the latter is much more serious than the former. In the greenhouse effect, although there are large uncertainties both in theoretical and observational sides, present predictions about the global warming will not be very far from reality. Environmental effects are wide-ranging and serious. Radon and thoron exhalation rates are affected by the global warming. The influence of the greenhouse effect on ozone depletion is to suppress depletion for conventional type and enhance depletion for ozone hole type. (author) 65 refs

  18. Global trends in radiation processing

    Defalco, Gerry

    2002-01-01

    A global leader in radioisotope technology with three business units: - Nuclear Medicine supplies about two-thirds of the world requirements for molybdenum-99 and other isotopes used to diagnose disease - Radiation Therapy business unit supplied more than over 2,300 cobalt cancer treatment machines and is a leader in treatment planning - Ion Technologies is the world's leading supplier of cobalt 60 and innovative gamma irradiation systems About Ion Technologies · Supply over 70% of world's cobalt-60 sources · Custom-designed and built irradiation systems · Comprehensive engineering, physics, logistics, installation and marketing services · Canadian Irradiation Center for unique 'hands on' training, R and D product irradiation

  19. The global mean energy balance under cloud-free conditions

    Wild, Martin; Hakuba, Maria; Folini, Dois; Ott, Patricia; Long, Charles

    2017-04-01

    A long standing problem of climate models is their overestimation of surface solar radiation not only under all-sky, but also under clear-sky conditions (Wild et al. 1995, Wild et al. 2006). This overestimation reduced over time in consecutive model generations due to the simulation of stronger atmospheric absorption. Here we analyze the clear sky fluxes of the latest climate model generation from the Coupled Model Intercomparison Project Phase 5 (CMIP5) against an expanded and updated set of direct observations from the Baseline Surface Radiation Network (BSRN). Clear sky climatologies from these sites have been composed based on the Long and Ackermann (2000) clear sky detection algorithm (Hakuba et al. 2017), and sampling issues when comparing with model simulated clear sky fluxes have been analyzed in Ott (2017). Overall, the overestimation of clear sky insolation in the CMIP5 models is now merely 1-2 Wm-2 in the multimodel mean, compared to 4 Wm-2 in CMIP3 and 6 Wm-2 in AMIPII (Wild et al. 2006). Still a considerable spread in the individual model biases is apparent, ranging from -2 Wm-2 to 10 Wm-2 when averaged over 53 globally distributed BSRN sites. This bias structure is used to infer best estimates for present day global mean clear sky insolation, following an approach developped in Wild et al. (2013, 2015, Clim. Dyn.) for all sky fluxes. Thereby the flux biases in the various models are linearly related to their respective global means. A best estimate can then be inferred from the linear regression at the intersect where the bias against the surface observations becomes zero. This way we obtain a best estimate of 247 Wm-2 for the global mean insolation at the Earth surface under cloud free conditions, and a global mean absorbed solar radiation of 214 Wm-2 in the cloud-free atmosphere, assuming a global mean surface albedo of 13.5%. Combined with a best estimate for the net influx of solar radiation at the Top of Atmosphere under cloud free conditions

  20. Global financial centers: shifting power balance

    Aalbers, M.B.

    2009-01-01

    London and New York are the most important global financial centers in the world. Tokyo used to be considered the third global financial center, but has lost its position in the last 20 years, partly as a result of a sustained recession and partly because both Japanese society and Japanese economy

  1. On the spectral composition of global radiation

    Major, G

    1983-01-01

    The global radiation is recorded at several stations on the Earth. The information about its spectral composition is poor. In this paper the spectral composition means the ratio of spectral global radiation measured by coloured glass filter domes to the total global radiation. From the measuements made by Klein and Goldberg it follows that the monthly ratios vary significantly from place to place, while the variations from month to month at one place are significant only at the station which lies near to the North Pole. The Budapest data proved the dominant effect of cloudiness on the spectral composition of global radiation. This effect is in good statistical relationship with the relative global radiation. The regression constant tabulated in this paper do not contain the error of zero point elevation which is due to the overheating of glass filters by the absorbed solar radiation.

  2. Radiation and energy balance of lettuce culture inside a polyethylene greenhouse

    Frisina, V. de A.; Escobedo, J.F.

    1999-01-01

    The objective of this paper was to describe the radiation and energy balance, during the lettuce (Lactuca sativa, L. cv. Verônica) crop cycle inside a polyethylene greenhouse. The radiation and energy balance was made inside a tunnel greenhouse with polyethylene cover (100 mm) and in an external area, both areas with 35 m 2 . Global, reflected and net radiation, soil heat flux and air temperature (dry and humid) were measured during the crop cycle. A Datalogger, which operated at 1 Hz frequency, storing 5 minutes averages was utilized. The global (K↓) and reflected (K) radiations showed that the average transmission of global radiation (K↓in / K↓ex) was almost constant, near to 79.59%, while the average ratio of reflected radiation (Kin / Kex) was 69.21% with 8.47% standard-deviation. The normalized curves of short-wave net radiation, in relation to the global radiation (K*/ K↓), found for both environments, were almost constant at the beginning of cycle; this relation decreased in the final stage of culture. The normalized relation (Rn/ K↓) was bigger in the external area, about 12%, when the green culture covered the soil surface. The long-wave radiation balance average (L*) was bigger outside, about 50%. The energy balance, estimated in terms of vertical fluxes, showed that, for the external area, in average, 83.07% of total net radiation was converted in latent heat evaporation (LE), and 18% in soil heat flux (G), and 9.96% in sensible heat (H), while inside of the greenhouse, 58.71% of total net radiation was converted in LE, 42.68% in H, and 28.79% in G. (author) [pt

  3. The Global Energy Balance Archive (GEBA): A database for the worldwide measured surface energy fluxes

    Wild, Martin; Ohmura, Atsumu; Schär, Christoph; Müller, Guido; Hakuba, Maria Z.; Mystakidis, Stefanos; Arsenovic, Pavle; Sanchez-Lorenzo, Arturo

    2017-02-01

    The Global Energy Balance Archive (GEBA) is a database for the worldwide measured energy fluxes at the Earth's surface. GEBA is maintained at ETH Zurich (Switzerland) and has been founded in the 1980s by Prof. Atsumu Ohmura. It has continuously been updated and currently contains around 2500 stations with 500`000 monthly mean entries of various surface energy balance components. Many of the records extend over several decades. The most widely measured quantity available in GEBA is the solar radiation incident at the Earth's surface ("global radiation"). The data sources include, in addition to the World Radiation Data Centre (WRDC) in St. Petersburg, data reports from National Weather Services, data from different research networks (BSRN, ARM, SURFRAD), data published in peer-reviewed publications and data obtained through personal communications. Different quality checks are applied to check for gross errors in the dataset. GEBA is used in various research applications, such as for the quantification of the global energy balance and its spatiotemporal variation, or for the estimation of long-term trends in the surface fluxes, which enabled the detection of multi-decadal variations in surface solar radiation, known as "global dimming" and "brightening". GEBA is further extensively used for the evaluation of climate models and satellite-derived surface flux products. On a more applied level, GEBA provides the basis for engineering applications in the context of solar power generation, water management, agricultural production and tourism. GEBA is publicly accessible over the internet via www.geba.ethz.ch.

  4. Radiation balance of an alfalfa crop in Saudi Arabia

    Al-Yemeni, M.N.; Grace, J.

    1995-01-01

    Short-wave reflectivity or albedo is an important component of net radiation which represents the major determinant of radiation balance of crop surface. This study was conducted on an irrigated alfalfa crop field at Al-Kharj agricultural area in Saudi Arabia, grown according to normal agricultural practices. Data on radiation balance and crop cover were collected over a number of days from March to October 1986, crop albedo varying from 0–4 in early morning to 0–20 at noon, the overall mean value of the crop albedo being estimated at 0–26. The relation between the individual components of radiation balance was studied, and a significant correlation between incident radiation and net radiation was found. Possible causes responsible for changes in crop albedo were discussed. (author)

  5. Infrared radiation in the energy balance of the upper atmosphere

    Gordiets, B.F.; Markov, M.N.

    1977-01-01

    The contribution of the infrared radiation to the energy balance of the Earth's upper atmosphere is discussed. The theoretical analysis has been carried out of the mechanisms of the transformation of the energy of outgoing particles and the ultraviolet-radiation of the Sun absorbed at the heights of Z >= 90 km into the infrared radiation. It is found out the the infrared radiation within the wave length range of 1.2-20 μ is more intensive that the 63 μ radiation of atomic oxygen and plays an important role in the general energy balance and the thermal regime of the thermosphere. It has been found out too that in the area of Z >= 120 km heights the radiation in the 5.3 μ NO band is the most intensive. This radiation is to be considered for the more accurate description of parameters of the atmosphere (temperature, density) conditioning the nature of the translocation of ionospheric sounds (ISS)

  6. Radiation balance in the sweet sorghum crop

    Assis, F.N. de; Mendez, M.E.G.; Martins, S.R.; Verona, L.A.

    1987-01-01

    The fluxes of incident solar radiation, reflected and net radiation were measured during the growing cicle of two fields of sweet sorghum (Sorghum bicolor L.), cus. BR-501 and BR-503, maintained under convenient irrigation level. Resultant data allowed to estimate the crop albedo as well as the estimates of Rn. (M.A.C.) [pt

  7. Radiation balance diversity on NW Spitsbergen in 2010–2014

    Kejna Marek

    2017-03-01

    Full Text Available This article presents the results of observations of selected fluxes of the radiation balance in north-western Spitsbergen in the years from 2010 to 2014. Measurements were taken in Ny-Ålesund and in the area of Kaffiøyra, on different surface types occurring in the Polar zone: moraine, tundra, snow and ice. Substantial differences in the radiation balance among the various types of surface were observed. The observations carried out in the summer seasons of 2010–2014 in the area of Kaffiøyra demonstrated that the considerable reflection of solar radiation on the Waldemar Glacier (albedo 55% resulted in a smaller solar energy net income. During the polar day, a diurnal course of the components of the radiation balance was apparently related to the solar elevation angle. When the sun was low over the horizon, the radiation balance became negative, especially on the glacier. Diurnal, annual and multi-annual variations in the radiation balance have a significant influence on the functioning of the environment in polar conditions.

  8. The Global Energy Balance Archive (GEBA) version 2017: a database for worldwide measured surface energy fluxes

    Wild, Martin; Ohmura, Atsumu; Schär, Christoph; Müller, Guido; Folini, Doris; Schwarz, Matthias; Zyta Hakuba, Maria; Sanchez-Lorenzo, Arturo

    2017-08-01

    The Global Energy Balance Archive (GEBA) is a database for the central storage of the worldwide measured energy fluxes at the Earth's surface, maintained at ETH Zurich (Switzerland). This paper documents the status of the GEBA version 2017 dataset, presents the new web interface and user access, and reviews the scientific impact that GEBA data had in various applications. GEBA has continuously been expanded and updated and contains in its 2017 version around 500 000 monthly mean entries of various surface energy balance components measured at 2500 locations. The database contains observations from 15 surface energy flux components, with the most widely measured quantity available in GEBA being the shortwave radiation incident at the Earth's surface (global radiation). Many of the historic records extend over several decades. GEBA contains monthly data from a variety of sources, namely from the World Radiation Data Centre (WRDC) in St. Petersburg, from national weather services, from different research networks (BSRN, ARM, SURFRAD), from peer-reviewed publications, project and data reports, and from personal communications. Quality checks are applied to test for gross errors in the dataset. GEBA has played a key role in various research applications, such as in the quantification of the global energy balance, in the discussion of the anomalous atmospheric shortwave absorption, and in the detection of multi-decadal variations in global radiation, known as global dimming and brightening. GEBA is further extensively used for the evaluation of climate models and satellite-derived surface flux products. On a more applied level, GEBA provides the basis for engineering applications in the context of solar power generation, water management, agricultural production and tourism. GEBA is publicly accessible through the internet via http://www.geba.ethz.ch. Supplementary data are available at https://doi.org/10.1594/PANGAEA.873078.

  9. Influence of soybean pubescence type on radiation balance

    Nielsen, D.C.; Blad, B.I.; Verma, S.B.; Rosenberg, N.J.; Specht, J.E.

    1984-01-01

    Increasing the density of pubescence on the leaves and stems of soybeans (Glycine max L.) should influence the radiation balance of the soybean canopy and affect the evapotranspiration and photosynthetic rates. This study was undertaken to evaluate the influence of increased pubescence density on various components of the radiation balance. Near-isogenic lines of two soybean cultivars (Clark and Harosoy) were grown in four adjacent small plots (18 m · 18 m) during the 1980, 1981, and 1982 growing seasons near Mead, Nebr. The soil at this site is classified as a Typic Argiudoll. The isolines of each cultivar varied only in the amount of pubescence (dense vs. normal pubescence). Measurements of albedo, reflected photosynthetically active radiation (PAR), emitted longwave radiation, and net radiation were made over the crop surfaces with instruments mounted on a rotating boom located at the intersection of the four plots. Radiative canopy temperatures were measured with a handheld infrared thermometer (IRT). Results show that dense pubescence increased reflection of shortwave radiation and PAR by 3 to 5% and 8 to 11%, respectively. Emitted longwave radiation and radiative canopy temperature were not significantly affected by increased pubescence, although there was a slight tendency for the dense pubescent canopy to be cooler. Increased pubescence decreased net radiation over the canopy by 0.5 to 1.5%. These results suggest that soybeans with dense pubescence may be slightly better adapted to the high radiation, high temperature, and limited moisture conditions of the eastern Great Plains than are those with normal pubescence

  10. Testing the performance of a Dynamic Global Ecosystem Model: Water balance, carbon balance, and vegetation structure

    Kucharik, Christopher J.; Foley, Jonathan A.; Delire, Christine; Fisher, Veronica A.; Coe, Michael T.; Lenters, John D.; Young-Molling, Christine; Ramankutty, Navin; Norman, John M.; Gower, Stith T.

    2000-09-01

    While a new class of Dynamic Global Ecosystem Models (DGEMs) has emerged in the past few years as an important tool for describing global biogeochemical cycles and atmosphere-biosphere interactions, these models are still largely untested. Here we analyze the behavior of a new DGEM and compare the results to global-scale observations of water balance, carbon balance, and vegetation structure. In this study, we use version 2 of the Integrated Biosphere Simulator (IBIS), which includes several major improvements and additions to the prototype model developed by Foley et al. [1996]. IBIS is designed to be a comprehensive model of the terrestrial biosphere; the model represents a wide range of processes, including land surface physics, canopy physiology, plant phenology, vegetation dynamics and competition, and carbon and nutrient cycling. The model generates global simulations of the surface water balance (e.g., runoff), the terrestrial carbon balance (e.g., net primary production, net ecosystem exchange, soil carbon, aboveground and belowground litter, and soil CO2 fluxes), and vegetation structure (e.g., biomass, leaf area index, and vegetation composition). In order to test the performance of the model, we have assembled a wide range of continental and global-scale data, including measurements of river discharge, net primary production, vegetation structure, root biomass, soil carbon, litter carbon, and soil CO2 flux. Using these field data and model results for the contemporary biosphere (1965-1994), our evaluation shows that simulated patterns of runoff, NPP, biomass, leaf area index, soil carbon, and total soil CO2 flux agree reasonably well with measurements that have been compiled from numerous ecosystems. These results also compare favorably to other global model results.

  11. Solar radiation, cloudiness and longwave radiation over low-latitude glaciers: implications for mass-balance modelling

    Mölg, Thomas; Cullen, Nicolas J.; Kaser, Georg

    Broadband radiation schemes (parameterizations) are commonly used tools in glacier mass-balance modelling, but their performance at high altitude in the tropics has not been evaluated in detail. Here we take advantage of a high-quality 2 year record of global radiation (G) and incoming longwave radiation (L↓) measured on Kersten Glacier, Kilimanjaro, East Africa, at 5873 m a.s.l., to optimize parameterizations of G and L↓. We show that the two radiation terms can be related by an effective cloud-cover fraction neff, so G or L↓ can be modelled based on neff derived from measured L↓ or G, respectively. At neff = 1, G is reduced to 35% of clear-sky G, and L↓ increases by 45-65% (depending on altitude) relative to clear-sky L↓. Validation for a 1 year dataset of G and L↓ obtained at 4850 m on Glaciar Artesonraju, Peruvian Andes, yields a satisfactory performance of the radiation scheme. Whether this performance is acceptable for mass-balance studies of tropical glaciers is explored by applying the data from Glaciar Artesonraju to a physically based mass-balance model, which requires, among others, G and L↓ as forcing variables. Uncertainties in modelled mass balance introduced by the radiation parameterizations do not exceed those that can be caused by errors in the radiation measurements. Hence, this paper provides a tool for inclusion in spatially distributed mass-balance modelling of tropical glaciers and/or extension of radiation data when only G or L↓ is measured.

  12. Temporal and spatial variability of global water balance

    McCabe, Gregory J.; Wolock, David M.

    2013-01-01

    An analysis of simulated global water-balance components (precipitation [P], actual evapotranspiration [AET], runoff [R], and potential evapotranspiration [PET]) for the past century indicates that P has been the primary driver of variability in R. Additionally, since about 2000, there have been increases in P, AET, R, and PET for most of the globe. The increases in R during 2000 through 2009 have occurred despite unprecedented increases in PET. The increases in R are the result of substantial increases in P during the cool Northern Hemisphere months (i.e. October through March) when PET increases were relatively small; the largest PET increases occurred during the warm Northern Hemisphere months (April through September). Additionally, for the 2000 through 2009 period, the latitudinal distribution of P departures appears to co-vary with the mean P departures from 16 climate model projections of the latitudinal response of P to warming, except in the high latitudes. Finally, changes in water-balance variables appear large from the perspective of departures from the long-term means. However, when put into the context of the magnitudes of the raw water balance variable values, there appears to have been little change in any of the water-balance variables over the past century on a global or hemispheric scale.

  13. India and the BRICS: Global Bandwagoning and Regional Balancing

    Matthew D Stephen

    2016-12-01

    Full Text Available Indian policy makers have welcomed India’s framing as a ‘rising power’ and celebrated the BRICS initiative as a common front in reforming aspects of global governance. Yet China’s rise in Asia has unsettled the balances of power which have underpinned the region, as a consequence of which India has hesitantly pursued a strategic rapprochement with the United States. Assessing New Delhi’s multilateral and geo-strategic diplomacy, this article argues that India bandwagons with the BRICS on a global level, but seeks to balance China at the regional level. On the global multilateral level, India has common cause with other rising powers in reforming the policies and structures of most international organizations. The exceptions are the United Nations Security Council and the Non-proliferation Treaty, where China and Russia can be qualified as established powers. On the regional level, however, India has maintained ties to Russia and cultivated a strong relationship with the United States in an effort to balance and increase leverage relative to a rising China. This underlines that major power rivalries are strongly mediated by issue area and institutional context.

  14. The global and UV-B radiation over Egypt

    BASSET, H. A.; KORANY, M. H.

    2007-01-01

    This work studies the relation between UV-B radiation and global radiation over Egypt. The relationships between the global solar radiation and UV-B radiation at four stations in Egypt have been studied, and linear empirical formulas for estimating UV-B from global radiation at these stations has been deduced. The deduced equations were applied to calculate the UV-B radiation for other stations where measurements were unavailable, using records of global radiation at these stations. Because o...

  15. Multisource Estimation of Long-term Global Terrestrial Surface Radiation

    Peng, L.; Sheffield, J.

    2017-12-01

    Land surface net radiation is the essential energy source at the earth's surface. It determines the surface energy budget and its partitioning, drives the hydrological cycle by providing available energy, and offers heat, light, and energy for biological processes. Individual components in net radiation have changed historically due to natural and anthropogenic climate change and land use change. Decadal variations in radiation such as global dimming or brightening have important implications for hydrological and carbon cycles. In order to assess the trends and variability of net radiation and evapotranspiration, there is a need for accurate estimates of long-term terrestrial surface radiation. While large progress in measuring top of atmosphere energy budget has been made, huge discrepancies exist among ground observations, satellite retrievals, and reanalysis fields of surface radiation, due to the lack of observational networks, the difficulty in measuring from space, and the uncertainty in algorithm parameters. To overcome the weakness of single source datasets, we propose a multi-source merging approach to fully utilize and combine multiple datasets of radiation components separately, as they are complementary in space and time. First, we conduct diagnostic analysis of multiple satellite and reanalysis datasets based on in-situ measurements such as Global Energy Balance Archive (GEBA), existing validation studies, and other information such as network density and consistency with other meteorological variables. Then, we calculate the optimal weighted average of multiple datasets by minimizing the variance of error between in-situ measurements and other observations. Finally, we quantify the uncertainties in the estimates of surface net radiation and employ physical constraints based on the surface energy balance to reduce these uncertainties. The final dataset is evaluated in terms of the long-term variability and its attribution to changes in individual

  16. Radiations in space and global environment

    Oguti, Takasi

    1994-01-01

    It has been well known that the global environment of the earth is basically determined by the radiation equilibrium of the earth atmosphere system embedded in the solar radiation. However, the surface temperature of about 15 degC on average is much higher than that determined by the radiation equilibrium. This is due to the so-called greenhouse gases in the atmosphere such as carbon dioxide, water vapor, methane and others. Also the global environment has evolved by interacting with the living things on the earth, for example, tree oxygen by photosynthesis, and a small amount of ozone protecting living things from the fetal damage due to solar ultraviolet radiation. The solar radiation of short wavelength, that is, ultraviolet to X-ray influences atmospheric constituents, and the thermal structure and dynamics of the atmosphere through chemical reaction. The solar energetic particles produced by solar flares precipitate in the polar regions, and the nitric oxides are produced by auroral X-ray. Auroral activities accelerate particles in the magnetosphere. All these radiations cause significant global changes. Human activities increase greenhouse gases rapidly and cause global warming, and atmospheric chloro-fluoro-carbon (CFC) makes the ozone hole. Now, human activities must be modified to match the natural cycle of materials. (K.I.)

  17. Global trends in radiation processing

    Defalco, G.

    2003-01-01

    There will be a brief introduction of the companies of MDS serving the Medical, Biotechnology and Pharmaceutical sectors worldwide. MDS Nordion will be introduced in more detail focused on the products and services of our Nuclear Medicine and Ion Technologies business units. World Trends and issues in Radiation Processing will be discussed on: Sterilization of Medical Devices, Pharmaceuticals, Cosmetics and Consumer products and finally I will present an overview on Food Irradiation progress worldwide

  18. Radiation balance in a deep Colorado valley: ASCOT 84

    Whiteman, C.D.; Fritschen, L.J.; Simpson, J.R.; Orgill, M.M.

    1984-12-01

    Five surface energy budget stations were installed at four sites in a deep, narrow valley in western Colorado as part of the Atmospheric Studies in Complex Terrain (ASCOT) Study. Radiation balance data are presented from these stations for the clear day September 29, 1984. 3 references, 3 figures, 3 tables

  19. Impact of climate forcing uncertainty and human water use on global and continental water balance components

    H. Müller Schmied

    2016-10-01

    Full Text Available The assessment of water balance components using global hydrological models is subject to climate forcing uncertainty as well as to an increasing intensity of human water use within the 20th century. The uncertainty of five state-of-the-art climate forcings and the resulting range of cell runoff that is simulated by the global hydrological model WaterGAP is presented. On the global land surface, about 62 % of precipitation evapotranspires, whereas 38 % discharges into oceans and inland sinks. During 1971–2000, evapotranspiration due to human water use amounted to almost 1 % of precipitation, while this anthropogenic water flow increased by a factor of approximately 5 between 1901 and 2010. Deviation of estimated global discharge from the ensemble mean due to climate forcing uncertainty is approximately 4 %. Precipitation uncertainty is the most important reason for the uncertainty of discharge and evapotranspiration, followed by shortwave downward radiation. At continental levels, deviations of water balance components due to uncertain climate forcing are higher, with the highest discharge deviations occurring for river discharge in Africa (−6 to 11 % from the ensemble mean. Uncertain climate forcings also affect the estimation of irrigation water use and thus the estimated human impact of river discharge. The uncertainty range of global irrigation water consumption amounts to approximately 50 % of the global sum of water consumption in the other water use sector.

  20. The Global Character of the Flux of Downward Longwave Radiation

    Stephens, Graeme L.; Wild, Martin; Stackhouse, Paul W., Jr.; L'Ecuyer, Tristan; Kato, Seiji; Henderson, David S.

    2012-01-01

    Four different types of estimates of the surface downwelling longwave radiative flux (DLR) are reviewed. One group of estimates synthesizes global cloud, aerosol, and other information in a radiation model that is used to calculate fluxes. Because these synthesis fluxes have been assessed against observations, the global-mean values of these fluxes are deemed to be the most credible of the four different categories reviewed. The global, annual mean DLR lies between approximately 344 and 350 W/sq m with an error of approximately +/-10 W/sq m that arises mostly from the uncertainty in atmospheric state that governs the estimation of the clear-sky emission. The authors conclude that the DLR derived from global climate models are biased low by approximately 10 W/sq m and even larger differences are found with respect to reanalysis climate data. The DLR inferred from a surface energy balance closure is also substantially smaller that the range found from synthesis products suggesting that current depictions of surface energy balance also require revision. The effect of clouds on the DLR, largely facilitated by the new cloud base information from the CloudSat radar, is estimated to lie in the range from 24 to 34 W/sq m for the global cloud radiative effect (all-sky minus clear-sky DLR). This effect is strongly modulated by the underlying water vapor that gives rise to a maximum sensitivity of the DLR to cloud occurring in the colder drier regions of the planet. The bottom of atmosphere (BOA) cloud effect directly contrast the effect of clouds on the top of atmosphere (TOA) fluxes that is maximum in regions of deepest and coldest clouds in the moist tropics.

  1. Radiative effects of global MODIS cloud regimes

    Oreopoulos, Lazaros; Cho, Nayeong; Lee, Dongmin; Kato, Seiji

    2018-01-01

    We update previously published MODIS global cloud regimes (CRs) using the latest MODIS cloud retrievals in the Collection 6 dataset. We implement a slightly different derivation method, investigate the composition of the regimes, and then proceed to examine several aspects of CR radiative appearance with the aid of various radiative flux datasets. Our results clearly show the CRs are radiatively distinct in terms of shortwave, longwave and their combined (total) cloud radiative effect. We show that we can clearly distinguish regimes based on whether they radiatively cool or warm the atmosphere, and thanks to radiative heating profiles to discern the vertical distribution of cooling and warming. Terra and Aqua comparisons provide information about the degree to which morning and afternoon occurrences of regimes affect the symmetry of CR radiative contribution. We examine how the radiative discrepancies among multiple irradiance datasets suffering from imperfect spatiotemporal matching depend on CR, and whether they are therefore related to the complexity of cloud structure, its interpretation by different observational systems, and its subsequent representation in radiative transfer calculations. PMID:29619289

  2. Radiative Effects of Global MODIS Cloud Regimes

    Oraiopoulos, Lazaros; Cho, Nayeong; Lee, Dong Min; Kato, Seiji

    2016-01-01

    We update previously published MODIS global cloud regimes (CRs) using the latest MODIS cloud retrievals in the Collection 6 dataset. We implement a slightly different derivation method, investigate the composition of the regimes, and then proceed to examine several aspects of CR radiative appearance with the aid of various radiative flux datasets. Our results clearly show the CRs are radiatively distinct in terms of shortwave, longwave and their combined (total) cloud radiative effect. We show that we can clearly distinguish regimes based on whether they radiatively cool or warm the atmosphere, and thanks to radiative heating profiles to discern the vertical distribution of cooling and warming. Terra and Aqua comparisons provide information about the degree to which morning and afternoon occurrences of regimes affect the symmetry of CR radiative contribution. We examine how the radiative discrepancies among multiple irradiance datasets suffering from imperfect spatiotemporal matching depend on CR, and whether they are therefore related to the complexity of cloud structure, its interpretation by different observational systems, and its subsequent representation in radiative transfer calculations.

  3. Spacebased Observation of Water Balance Over Global Oceans

    Liu, W.; Xie, X.

    2008-12-01

    We demonstrated that ocean surface fresh water flux less the water discharge into the ocean from river and ice melt balances the mass loss in the ocean both in magnitude and in the phase of annual variation. The surface water flux was computed from the divergence of the water transport integrated over the depth of the atmosphere. The atmospheric water transport is estimated from the precipitable water measured by Special Sensor Microwave Imager, the surface wind vector by QuikSCAT, and the NOAA cloud drift wind through a statistical model. The transport has been extensively validated using global radiosonde and data and operational numerical weather prediction results. Its divergence has been shown to agree with the difference between evaporation estimated from the Advanced Microwave Scanning Radiometer data and the precipitation measured by Tropical Rain Measuring Mission over the global tropical and subtropical oceans both in magnitude and geographical distribution for temporal scales ranging from intraseasonal to interannual. The water loss rate in the ocean is estimated by two methods, one is from Gravity Recovery and Climate Experiment and the other is by subtracting the climatological steric change from the sea level change measured by radar altimeter on Jason. Only climatological river discharge and ice melt from in situ measurements are available and the lack of temporal variation may contribute to discrepancies in the balance. We have successfully used the spacebased surface fluxes to estimate to climatological mean heat transport in the Atlantic ocean and is attempting to estimate the meridional fresh water (or salt) transport from the surface flux. The approximate closure of the water balance gives a powerful indirect validation of the spacebased products.

  4. Radiation dose to the global flying population

    Alvarez, Luis E; Eastham, Sebastian D; Barrett, Steven R H

    2016-01-01

    Civil airliner passengers and crew are exposed to elevated levels of radiation relative to being at sea level. Previous studies have assessed the radiation dose received in particular cases or for cohort studies. Here we present the first estimate of the total radiation dose received by the worldwide civilian flying population. We simulated flights globally from 2000 to 2013 using schedule data, applying a radiation propagation code to estimate the dose associated with each flight. Passengers flying in Europe and North America exceed the International Commission on Radiological Protection annual dose limits at an annual average of 510 or 420 flight hours per year, respectively. However, this falls to 160 or 120 h on specific routes under maximum exposure conditions. (paper)

  5. Balancing needs. Global trends in uranium production and demand

    Nicolet, J.P.; Underhill, D.

    1998-01-01

    In many countries, uranium is a major energy resource, fueling nuclear power plants that collectively generate about 17% of the world's electricity. With global demand for energy especially electricity projected to grow rapidly over the coming decades, the price and availability of all energy sources, including uranium, are key components in the process of energy planning and decision-making. Particularly affecting the uranium market were changing projections about nuclear power's growth and the consequent demand for nuclear fuel; the emergence of a more integrated free market system including former centrally planned economies; and the emergence into the civilian market of uranium released from dismantled nuclear weapons. All these factors contributed to uncertainties in the commercial uranium market that raised questions about future fuel supplies for nuclear power plants. Signs today indicate that the situation is changing. The world uranium market is moving towards a more balanced relationship between supply and demand

  6. GERMON. Global Environmental Radiation Monitoring Network

    1992-01-01

    Between 15-18 December 1987, a meeting of experts of WHO/UNEP met at Le Vesinet, France, to develop the basic principles of a global environmental radiation monitoring network (GERMON) which would have the function of reporting on a regular basis environmental radiation levels, and be positioned to provide rapid and reliable radiation measurements in the event of a major radiation release. To date, some 58 countries have indicated their willingness to become part of GERMON. About 40 of these have technical staff and equipment to meet the minimum requirements for joining the network, and about 30 have designated appropriate organizations within their country to serve as national Liaison Institutions for GERMON. Sixteen countries are now providing data on a regular basis to the CCC at SCPRI in Le Vesinet, France. Thirty-two countries responded to the request of WHO for readiness to take part in a IAEA radiation emergency exercise. The present meeting has been held in Montgomery, Alabama, USA at the National Air and Radiation Environmental Laboratory between 27 April 1992 and 30 April 1992, with the purpose of reviewing GERMON. One important topic considered was the implementation of GERMON in the Americas. Particular attention was given to the need for better coordination with IAEA in responding to the Convention on Early Notification, to the role of the CCC, to forms of data transmission, etc

  7. The global assessment of medical radiation exposures

    Shannoun, F.

    2010-01-01

    World Health Organization (WHO) is the United Nations specialized agency which acts as a coordinating authority on international public health. It was established in 1948. It has 147 Country Offices, 6 Regional Offices and 193 Member States Ministries of Health Its headquarters is in Geneva. The World Health Assembly (WHA) requested WHO to s tudy the optimum use of ionizing radiation in medicine and the risks to health of excessive or improper use . (WHA, 1971) International Basic Safety Standards BSS) The (BSS) mark the culmination of efforts towards global harmonization of radiation safety requirements. However, the involvement of the health sector in the BSS implementation is still weak and scant. There is a need to mobilize the health sector towards safer and effective use of radiation in medicine. Radiation in Health Care The use of radiation in health care is by far the largest contributor to the exposure of the general population from artificial sources. Annually worldwide there are 3,600 million X-ray exams (> 300 million in children), 37 million nuclear medicine procedures and 7.5 million radiation oncology treatments [UNSCEAR Report 2008]. WHO Global Initiative on Radiation Safety in Health Care Settings Was launched in December 2008 It involved the following:- There was involvement of international organizations and professionals bodies, national health and radiation protection authorities, etc. Its aim is to improve the protection of patients and health care workers through better implementation of the BSS. It complements the International Action Plan for Radiological Protection of Patients established by the IAEA 7 UNSCEAR's medical exposure survey Objectives of UNSCEAR's survey were to facilitate evaluation of: - Global estimates of frequency and levels of exposures, with break-downs by medical procedure, age, sex, health care level, and country; - Trends in practice (including those relatively fast-changing); with supporting contextual

  8. The Global Environment Radiation Monitoring Network (GERMON)

    Zakheim, B.J.; Goellner, D.A.

    1994-01-01

    Following the Chernobyl accident in 1986, a group of experts from the World Health Organization (WHO) and the United Nations Environment Program (UNEP) met in France to discuss and develop the basic principles of a global environmental radiation monitoring network (GERMON). The basic functions of this network were to provide regular reports on environmental radiation levels and to be in a position to provide reliable and accurate radiation measurements on a quick and accurate radiation measurements on a quick turnaround basis in the event of a major radiation release. By 1992, although 58 countries had indicated an interest in becoming a part of the GERMON system, only 16 were providing data on a regular basis. This paper traces the history of GERMON from its inception in 1987 through its activities during 1993-4. It details the objectives of the network, describes functions, lists its participants, and presents obstacles in the current network. The paper examines the data requirements for radiological emergency preparedness and offers suggestions for the current system. The paper also describes the growing need for such a network. To add a domestic perspective, the authors present a summary of the environmental monitoring information system that was used by the NRC in 1986 in its analyses of the Chernobyl incident. Then we will use this 1986 experience to propose a method for the use of GERMON should a similar occasion arise in the future

  9. Surface energy and radiation balance systems - General description and improvements

    Fritschen, Leo J.; Simpson, James R.

    1989-01-01

    Surface evaluation of sensible and latent heat flux densities and the components of the radiation balance were desired for various vegetative surfaces during the ASCOT84 experiment to compare with modeled results and to relate these values to drainage winds. Five battery operated data systems equipped with sensors to determine the above values were operated for 105 station days during the ASCOT84 experiment. The Bowen ratio energy balance technique was used to partition the available energy into the sensible and latent heat flux densities. A description of the sensors and battery operated equipment used to collect and process the data is presented. In addition, improvements and modifications made since the 1984 experiment are given. Details of calculations of soil heat flow at the surface and an alternate method to calculate sensible and latent heat flux densities are provided.

  10. 77 FR 14832 - Plumchoice, Inc., Including On-Site Leased Workers From Balance Staffing, Insight Global Staffing...

    2012-03-13

    ...., Including On-Site Leased Workers From Balance Staffing, Insight Global Staffing, and Technisource..., Insight Global Staffing, and Technisource, Scarborough, Maine. The workers are engaged in activities... leased workers from Balance Staffing, Insight Global Staffing, and Technisource, Scarborough, Maine, who...

  11. Calibration of a surface mass balance model for global-scale applications

    Giesen, R. H.; Oerlemans, J.

    2012-01-01

    Global applications of surface mass balance models have large uncertainties, as a result of poor climate input data and limited availability of mass balance measurements. This study addresses several possible consequences of these limitations for the modelled mass balance. This is done by applying a

  12. Models for prediction of global solar radiation on horizontal surface ...

    The estimation of global solar radiation continues to play a fundamental role in solar engineering systems and applications. This paper compares various models for estimating the average monthly global solar radiation on horizontal surface for Akure, Nigeria, using solar radiation and sunshine duration data covering years ...

  13. Balancing accuracy, efficiency, and flexibility in a radiative transfer parameterization for dynamical models

    Pincus, R.; Mlawer, E. J.

    2017-12-01

    Radiation is key process in numerical models of the atmosphere. The problem is well-understood and the parameterization of radiation has seen relatively few conceptual advances in the past 15 years. It is nonthelss often the single most expensive component of all physical parameterizations despite being computed less frequently than other terms. This combination of cost and maturity suggests value in a single radiation parameterization that could be shared across models; devoting effort to a single parameterization might allow for fine tuning for efficiency. The challenge lies in the coupling of this parameterization to many disparate representations of clouds and aerosols. This talk will describe RRTMGP, a new radiation parameterization that seeks to balance efficiency and flexibility. This balance is struck by isolating computational tasks in "kernels" that expose as much fine-grained parallelism as possible. These have simple interfaces and are interoperable across programming languages so that they might be repalced by alternative implementations in domain-specific langauges. Coupling to the host model makes use of object-oriented features of Fortran 2003, minimizing branching within the kernels and the amount of data that must be transferred. We will show accuracy and efficiency results for a globally-representative set of atmospheric profiles using a relatively high-resolution spectral discretization.

  14. A mathematical correlation between variations in solar radiation parameters - I: Daily sums of global radiation and midday global radiation

    Njau, E.C.

    1987-11-01

    An equation that simply relates variations in the daily sums of global radiation and the corresponding midday global radiation data over an arbitrarily chosen location on the Earth is derived from first principles. Although this equation is specifically tailored for periods incorporating only cloudless days, it is modified slightly in order also to suit any period that incorporates either cloudless days or consistently cloudy days or days characterised by consistently distributed cloud patches or any combination of these. Global radiation data for Dar es Salaam, Tanzania, calculated on the basis of the slightly modified version of the equation mentioned above agree with actual measurements to at least 89% if each of the days involved is either fairly cloudless or consistently cloudy or is characterised by fairly consistent cloud patches from sunrise to sunset. This clearly demonstrates that it is quite possible to work out reasonable estimates of the overall global radiation incident on a given area using only the corresponding midday global radiation data for that particular area. (author). 6 refs, 1 fig, 3 tabs

  15. The phase lag of temperature behind global solar radiation

    El Hussainy, F.M.

    1995-08-01

    This paper presented the relationship between the air temperature and the global solar radiation, which can be conveniently represented by the three characteristics: mean, amplitude and phase lag of the first harmonic of global radiation and air temperatures. A good correlation between the air temperature and the global solar radiation has been found when the phase lag between them is nearly of 30 days. (author). 4 refs, 9 figs, 1 tab

  16. Global energy balance - 2009 - Gerdau Acominas - Presidente Arthur Bernardes plant; Balanco energetico global - 2009 - Gerdau Acominas - Usina Presidente Arthur Bernardes

    Coelho, Almir de Freitas Pinto; Moura, Cassio Melo

    2010-07-01

    The global energy balance of Gerdau Acominas 2009, with the main energetic consumption indicators of the producer areas is presented. Besides the global energetic indicators, the balance presents the physical specific insums of the diverse areas, allowing the analysis of each plant sector in independent way. During the year 2009 it his highlighted the following points: production reduction due to the word economic crisis; 25 years revision of the boilers; stop of de blast-furnace 1 and the coke plant 2.

  17. Radiation dose in mammography: an energy-balance approach

    Shrivastava, P.N.

    1981-01-01

    An energy-balance approach for calculation of mean, integral, and midpoint doses in mammography is introduced. Estimation of mean absorbed dose for individual applications is described. Calculations made for a range of xeromammographic techniques used at various breast cancer detection centers show that although increasing the beam h.v.l. dramatically decreases breast surface exposure, it is insignificant in lowering mean breast dose or radiation risk. Thus selection of a moderate h.v.l. to optimize image quality in xeromammography may be more beneficial than unduly increasing h.v.l. merely to reduce surface exposure. The mean breast dose per mammogram with low h.v.l. screen-film techniques was 3 to 9 times lower than for xeromammography, suggesting that general acceptance of screen-film techniques can significantly reduce the risk associated with mammography

  18. Radiation dose in mammography: an energy-balance approach

    Shrivastava, P.N.

    1981-01-01

    An energy-balance approach for calculation of mean, integral, and midpoint doses in mammography is introduced. Estimation of mean absorbed dose for individual applications is described. Differences in breast composition and thickness are accounted for by simple measurements of entrance and exit exposures. Calculations made for a range of xeromammographic techniques used at various breast cancer detection centers show that although increasing the beam h.v.l. dramatically decreases breast surface exposure, it is insignificant in lowering mean breast dose or radiation risk. Thus selection of a moderate h.v.l. to optimize image quality (soft-tissue contrast) in xeromammography may be more beneficial than unduly increasing h.v.l. merely to reduce surface exposure. The mean breast dose per mammogram with low-h.v.l. screen-film techniques was 3 to 9 times lower than for xeromammography, suggesting that general acceptance of screen-film techniques can significantly reduce the risk associated with mammography

  19. Conceptual understanding of climate change with a globally resolved energy balance model

    Dommenget, Dietmar [Monash University, School of Mathematical Sciences, Melbourne, VIC (Australia); Floeter, Janine [Leibniz Institute for Marine Sciences, Kiel (Germany)

    2011-12-15

    The future climate change projections are essentially based on coupled general circulation model (CGCM) simulations, which give a distinct global warming pattern with arctic winter amplification, an equilibrium land-sea warming contrast and an inter-hemispheric warming gradient. While these simulations are the most important tool of the Intergovernmental Panel on Climate Change (IPCC) predictions, the conceptual understanding of these predicted structures of climate change and the causes of their uncertainties is very difficult to reach if only based on these highly complex CGCM simulations. In the study presented here we will introduce a very simple, globally resolved energy balance (GREB) model, which is capable of simulating the main characteristics of global warming. The model shall give a bridge between the strongly simplified energy balance models and the fully coupled 4-dimensional complex CGCMs. It provides a fast tool for the conceptual understanding and development of hypotheses for climate change studies, which shall build a basis or starting point for more detailed studies of observations and CGCM simulations. It is based on the surface energy balance by very simple representations of solar and thermal radiation, the atmospheric hydrological cycle, sensible turbulent heat flux, transport by the mean atmospheric circulation and heat exchange with the deeper ocean. Despite some limitations in the representations of the basic processes, the models climate sensitivity and the spatial structure of the warming pattern are within the uncertainties of the IPCC models simulations. It is capable of simulating aspects of the arctic winter amplification, the equilibrium land-sea warming contrast and the inter-hemispheric warming gradient with good agreement to the IPCC models in amplitude and structure. The results give some insight into the understanding of the land-sea contrast and the polar amplification. The GREB model suggests that the regional inhomogeneous

  20. Modifying a dynamic global vegetation model for simulating large spatial scale land surface water balance

    Tang, G.; Bartlein, P. J.

    2012-01-01

    Water balance models of simple structure are easier to grasp and more clearly connect cause and effect than models of complex structure. Such models are essential for studying large spatial scale land surface water balance in the context of climate and land cover change, both natural and anthropogenic. This study aims to (i) develop a large spatial scale water balance model by modifying a dynamic global vegetation model (DGVM), and (ii) test the model's performance in simulating actual evapotranspiration (ET), soil moisture and surface runoff for the coterminous United States (US). Toward these ends, we first introduced development of the "LPJ-Hydrology" (LH) model by incorporating satellite-based land covers into the Lund-Potsdam-Jena (LPJ) DGVM instead of dynamically simulating them. We then ran LH using historical (1982-2006) climate data and satellite-based land covers at 2.5 arc-min grid cells. The simulated ET, soil moisture and surface runoff were compared to existing sets of observed or simulated data for the US. The results indicated that LH captures well the variation of monthly actual ET (R2 = 0.61, p 0.46, p 0.52) with observed values over the years 1982-2006, respectively. The modeled spatial patterns of annual ET and surface runoff are in accordance with previously published data. Compared to its predecessor, LH simulates better monthly stream flow in winter and early spring by incorporating effects of solar radiation on snowmelt. Overall, this study proves the feasibility of incorporating satellite-based land-covers into a DGVM for simulating large spatial scale land surface water balance. LH developed in this study should be a useful tool for studying effects of climate and land cover change on land surface hydrology at large spatial scales.

  1. Inside the Mustard Seed: Toward a Gender-Balanced Global Education.

    Kobus, Doni Kwolek

    1989-01-01

    Considers three issues related to gender-balanced global education: gender's place in the social studies; survey results on awareness and implementation of the National Council for the Social Studies' resolution on gender in global education; and criteria for evaluating global education materials. (DB)

  2. Effects of aerosol from biomass burning on the global radiation budget

    Penner, Joyce E.; Dickinson, Robert E.; O'Neill, Christine A.

    1992-01-01

    An analysis is made of the likely contribution of smoke particles from biomass burning to the global radiation balance. These particles act to reflect solar radiation directly; they also can act as cloud condensation nuclei, increasing the reflectivity of clouds. Together these effects, although uncertain, may add up globally to a cooling effect as large as 2 watts per square meter, comparable to the estimated contribution to sulfate aerosols. Anthropogenic increases of smoke emission thus may have helped weaken the net greenhouse warming from anthropogenic trace gases.

  3. Impacts of climate mitigation strategies in the energy sector on global land use and carbon balance

    Engström, Kerstin; Lindeskog, Mats; Olin, Stefan; Hassler, John; Smith, Benjamin

    2017-09-01

    Reducing greenhouse gas emissions to limit damage to the global economy climate-change-induced and secure the livelihoods of future generations requires ambitious mitigation strategies. The introduction of a global carbon tax on fossil fuels is tested here as a mitigation strategy to reduce atmospheric CO2 concentrations and radiative forcing. Taxation of fossil fuels potentially leads to changed composition of energy sources, including a larger relative contribution from bioenergy. Further, the introduction of a mitigation strategy reduces climate-change-induced damage to the global economy, and thus can indirectly affect consumption patterns and investments in agricultural technologies and yield enhancement. Here we assess the implications of changes in bioenergy demand as well as the indirectly caused changes in consumption and crop yields for global and national cropland area and terrestrial biosphere carbon balance. We apply a novel integrated assessment modelling framework, combining three previously published models (a climate-economy model, a socio-economic land use model and an ecosystem model). We develop reference and mitigation scenarios based on the narratives and key elements of the shared socio-economic pathways (SSPs). Taking emissions from the land use sector into account, we find that the introduction of a global carbon tax on the fossil fuel sector is an effective mitigation strategy only for scenarios with low population development and strong sustainability criteria (SSP1 Taking the green road). For scenarios with high population growth, low technological development and bioenergy production the high demand for cropland causes the terrestrial biosphere to switch from being a carbon sink to a source by the end of the 21st century.

  4. Impacts of climate mitigation strategies in the energy sector on global land use and carbon balance

    K. Engström

    2017-09-01

    Full Text Available Reducing greenhouse gas emissions to limit damage to the global economy climate-change-induced and secure the livelihoods of future generations requires ambitious mitigation strategies. The introduction of a global carbon tax on fossil fuels is tested here as a mitigation strategy to reduce atmospheric CO2 concentrations and radiative forcing. Taxation of fossil fuels potentially leads to changed composition of energy sources, including a larger relative contribution from bioenergy. Further, the introduction of a mitigation strategy reduces climate-change-induced damage to the global economy, and thus can indirectly affect consumption patterns and investments in agricultural technologies and yield enhancement. Here we assess the implications of changes in bioenergy demand as well as the indirectly caused changes in consumption and crop yields for global and national cropland area and terrestrial biosphere carbon balance. We apply a novel integrated assessment modelling framework, combining three previously published models (a climate–economy model, a socio-economic land use model and an ecosystem model. We develop reference and mitigation scenarios based on the narratives and key elements of the shared socio-economic pathways (SSPs. Taking emissions from the land use sector into account, we find that the introduction of a global carbon tax on the fossil fuel sector is an effective mitigation strategy only for scenarios with low population development and strong sustainability criteria (SSP1 Taking the green road. For scenarios with high population growth, low technological development and bioenergy production the high demand for cropland causes the terrestrial biosphere to switch from being a carbon sink to a source by the end of the 21st century.

  5. Actual global problems of radiation protection

    Ninkovic, M.

    1995-01-01

    Personal views on some actual problems in radiation protection are given in this paper. Among these problems are: evolution methodology used in radiation protection regulations; radiation protection, nuclear energy and safety, and new approaches to the process of the hazardous substances management. An interesting fact relating to the X-ray, radiation protection and Nikola Tesla are given also. (author)

  6. Spatial distribution of coefficients for determination of global radiation in Serbia

    Nikolić Jugoslav L.

    2012-01-01

    Full Text Available The aim of this paper is a creation of the spatial distribution of the corresponding coefficients for the indirect determination of global radiation using all direct measurements data of this shortwave radiation balance component in Serbia in the standard climate period (1961-1990. Based on the global radiation direct measurements data recorded in the past and routine measurements/observations of cloudiness and sunshine duration, the spatial distribution coefficients maps required for calculation of global radiation were produced on the basis of sunshine/cloudiness in an arbitrary point on the territory of Serbia. Besides, a specific verification of the proposed empirical formula was performed. This paper contributes to a wide range of practical applications as direct measurements of global radiation are relatively rare, and are not carried out in Serbia today. Significant application is possible in the domain of renewable energy sources. The development of method for determination of the global radiation has an importance from the aspect of the environmental protection; however it also has an economic importance through applications in numerous commercial projects, as it does not require special measurements or additional financial investments.

  7. Estimation of diffuse from measured global solar radiation

    Moriarty, W.W.

    1991-01-01

    A data set of quality controlled radiation observations from stations scattered throughout Australia was formed and further screened to remove residual doubtful observations. It was then divided into groups by solar elevation, and used to find average relationships for each elevation group between relative global radiation (clearness index - the measured global radiation expressed as a proportion of the radiation on a horizontal surface at the top of the atmosphere) and relative diffuse radiation. Clear-cut relationships were found, which were then fitted by polynomial expressions giving the relative diffuse radiation as a function of relative global radiation and solar elevation. When these expressions were used to estimate the diffuse radiation from the global, the results had a slightly smaller spread of errors than those from an earlier technique given by Spencer. It was found that the errors were related to cloud amount, and further relationships were developed giving the errors as functions of global radiation, solar elevation, and the fraction of sky obscured by high cloud and by opaque (low and middle level) cloud. When these relationships were used to adjust the first estimates of diffuse radiation, there was a considerable reduction in the number of large errors

  8. Use of MODIS Images to Quantify the Radiation and Energy Balances in the Brazilian Pantanal

    Antônio H. de C. Teixeira

    2015-11-01

    Full Text Available MODIS images during the year 2012 were used for modelling of the radiation and energy balance components with the application of the SAFER algorithm (Simple Algorithm for Evapotranspiration Retrieving in the Brazilian Pantanal area. Pixels from the main sub-regions of Barão de Melgaço (BR, Paiaguás (PA and Nhecolândia (NH were extracted in order to process microclimatic comparisons. In general, the net radiation (Rn relied much more on the global solar radiation (RG levels than on water conditions and ecosystem types, in accordance with the low Rn standard deviation values. The fraction of the available energy used as latent heat flux (λE were, on average, 65, 50 and 49% for the BR, PA and NH sub-regions, respectively. Horizontal heat advection, identified by the negative values of sensible heat flux (H, made several pixels with λE values higher than those for Rn in the middle of the year. Taking the evaporative fraction (Ef as a surface moisture indicator, the Tree-Lined Savanna (TLS was considered the moister ecosystem class, with 58% of the available energy being used as λE, while the driest one was the modified ecosystem Anthropogenic Changes (AC, presenting a λE/Rn fraction of 0.46. According to the spatial and temporal consistencies, and after comparisons with other previous point and large-scale studies, the SAFER algorithm proved to have sensibility to quantify and compare the large-scale radiation and energy balance components in the different ecosystems of the Brazilian Pantanal. The algorithm is useful for monitoring the energy exchange dynamics among the different terrestrial and aquatic ecosystem types throughout the seasons of the year.

  9. Evaluation of global solar radiation models for Shanghai, China

    Yao, Wanxiang; Li, Zhengrong; Wang, Yuyan; Jiang, Fujian; Hu, Lingzhou

    2014-01-01

    Highlights: • 108 existing models are compared and analyzed by 42 years meteorological data. • Fitting models based on measured data are established according to 42 years data. • All models are compared by recently 10 years meteorological data. • The results show that polynomial models are the most accurate models. - Abstract: In this paper, 89 existing monthly average daily global solar radiation models and 19 existing daily global solar radiation models are compared and analyzed by 42 years meteorological data. The results show that for existing monthly average daily global solar radiation models, linear models and polynomial models have been able to estimate global solar radiation accurately, and complex equation types cannot obviously improve the precision. Considering direct parameters such as latitude, altitude, solar altitude and sunshine duration can help improve the accuracy of the models, but indirect parameters cannot. For existing daily global solar radiation models, multi-parameter models are more accurate than single-parameter models, polynomial models are more accurate than linear models. Then measured data fitting monthly average daily global solar radiation models (MADGSR models) and daily global solar radiation models (DGSR models) are established according to 42 years meteorological data. Finally, existing models and fitting models based on measured data are comparative analysis by recent 10 years meteorological data, and the results show that polynomial models (MADGSR model 2, DGSR model 2 and Maduekwe model 2) are the most accurate models

  10. TerraClimate, a high-resolution global dataset of monthly climate and climatic water balance from 1958-2015

    Abatzoglou, John T.; Dobrowski, Solomon Z.; Parks, Sean A.; Hegewisch, Katherine C.

    2018-01-01

    We present TerraClimate, a dataset of high-spatial resolution (1/24°, ~4-km) monthly climate and climatic water balance for global terrestrial surfaces from 1958-2015. TerraClimate uses climatically aided interpolation, combining high-spatial resolution climatological normals from the WorldClim dataset, with coarser resolution time varying (i.e., monthly) data from other sources to produce a monthly dataset of precipitation, maximum and minimum temperature, wind speed, vapor pressure, and solar radiation. TerraClimate additionally produces monthly surface water balance datasets using a water balance model that incorporates reference evapotranspiration, precipitation, temperature, and interpolated plant extractable soil water capacity. These data provide important inputs for ecological and hydrological studies at global scales that require high spatial resolution and time varying climate and climatic water balance data. We validated spatiotemporal aspects of TerraClimate using annual temperature, precipitation, and calculated reference evapotranspiration from station data, as well as annual runoff from streamflow gauges. TerraClimate datasets showed noted improvement in overall mean absolute error and increased spatial realism relative to coarser resolution gridded datasets.

  11. Partitioning of radiation and energy balance components in an inhomogeneous desert valley

    Malek, E.; Bingham, G.E.

    1997-01-01

    Radiation and energy balance components are required to validate global, regional, and local scale models representing surface heat flux relationships in the heterogeneous surfaces of the world's arid and desert regions. Research was conducted in north-eastern Nevada, U.S.A., in a Great Basin inhomogeneous semi-arid desert valley located at 40° 44′ N, 114° 26′ W, with an elevation of 1707 m above mean sea level, to study the daily, monthly, and annual mesoscale radiation and energy balance components. We established five radiation stations along with five Bowen ratio systems to measure the incoming (R si ) and outgoing (R so ) solar (shortwave) radiation, net (R n ) radiation, air temperatures and moisture at 1 and 2 m above-ground, the aggregated (soil + vegetation) surface temperature, soil heat flux at 8 cm (three locations at each station), soil temperatures at 2 and 6 cm above each soil flux plate, wind speed and direction at 10 m, and precipitation (if any) every 5 s averaged into 20 min throughout the valley during the 93–94 water year (beginning 1 October). Our study during the 93–94 water year showed that albedo (R so /R si ) ranged from 85% (snow-covered surface) to 10% (cloudy skies with wet surface) among stations. The water year total incoming solar radiation (averaged among stations) amounted to 6·33 × 10 3 MJ·m −2 and about 24% of that was reflected back to the atmosphere. The net longwave radiation (R ln = R lo − R li ) was about 32% of R si , where R lo and R li are the terrestrial (outgoing) and atmospheric (incoming) longwave radiation, respectively. The 93–94 water year average net radiation (R n ) among stations amounted to 2·68 × 10 3 MJ·m −2 (about 44% of R si ). Approximately 85·3% and 14·6% of R n were used for the processes of sensible (H) and latent (LE) heat fluxes, respectively. The annual R n contribution to surface soil heat flux (G surf ) was almost 0·1%. Monthly and annual relationships among

  12. The energy balance experiment EBEX-2000. Part III: Behaviour and quality of the radiation measurements

    Kohsiek, W.; Liebethal, C.; Foken, T.; Vogt, R.; Oncley, S.P.; Bernhofer, C.; Debruin, H.A.R.

    2007-01-01

    An important part of the Energy Balance Experiment (EBEX-2000) was the measurement of the net radiation and its components. Since the terrain, an irrigated cotton field, could not be considered homogeneous, radiation measurements were made at nine sites using a variety of radiation instruments,

  13. Balancing Attended and Global Stimuli in Perceived Video Quality Assessment

    You, Junyong; Korhonen, Jari; Perkis, Andrew

    2011-01-01

    . This paper proposes a quality model based on the late attention selection theory, assuming that the video quality is perceived via two mechanisms: global and local quality assessment. First we model several visual features influencing the visual attention in quality assessment scenarios to derive......The visual attention mechanism plays a key role in the human perception system and it has a significant impact on our assessment of perceived video quality. In spite of receiving less attention from the viewers, unattended stimuli can still contribute to the understanding of the visual content...... an attention map using appropriate fusion techniques. The global quality assessment as based on the assumption that viewers allocate their attention equally to the entire visual scene, is modeled by four carefully designed quality features. By employing these same quality features, the local quality model...

  14. Measurement of global solar radiation over Brunei Darussalam

    Malik, A.Q.; Ak Abd Malik Abd Raub Pg Ghani

    2006-01-01

    Measurements of global solar radiation on a horizontal surface were carried out for a period of 11 months starting from June 2001 to April 2002. The pyrano meter (Kipp and Zonen) was placed at the top of the library building of University of Brunei Darussalam, which affords optimum exposure to the instrument sensor without appreciable obstacle for incoming global radiation. The maximum and minimum monthly-averaged global irradiations of 553 W/m 2 and 433 W/m 2 were recorded for the months of March and October respectively. The variation of global solar radiation can be divided into two distinct groups - the low radiation values being associated with cloud and turbidity while the high values are associated with less turbid and cloudy periods

  15. Reliability of cervical lordosis and global sagittal spinal balance measurements in adolescent idiopathic scoliosis.

    Vidal, Christophe; Ilharreborde, Brice; Azoulay, Robin; Sebag, Guy; Mazda, Keyvan

    2013-06-01

    Radiological reproducibility study. To assess intra and interobserver reliability of radiographic measurements for global sagittal balance parameters and sagittal spine curves, including cervical spine. Sagittal spine balance in adolescent idiopathic scoliosis (AIS) is a main issue and many studies have been reported, showing that coronal and sagittal deformities often involve sagittal cervical unbalance. Global sagittal balance aims to obtain a horizontal gaze and gravity line at top of hips when subject is in a static position, involving adjustment of each spine curvature in the sagittal plane. To our knowledge, no study did use a methodologically validated imaging analysis tool able to appreciate sagittal spine contours and distances in AIS and especially in the cervical region. Lateral full-spine low-dose EOS radiographs were performed in 75 patients divided in three groups (control subjects, AIS, operated AIS). Three observers digitally analyzed twice each radiograph and 11 sagittal measures were collected for each image. Reliability was assessed calculating intraobserver Pearson's r correlation coefficient, interobserver intra-class correlation coefficient (ICC) completed with a two-by-two Bland-Altman plot analysis. This measurement method has shown excellent intra and interobserver reliability in all parameters, sagittal curvatures, pelvic parameters and global sagittal balance. This study validated a simple and efficient tool in AIS sagittal contour analysis. It defined new relevant landmarks allowing to characterize cervical segmental curvatures and cervical involvement in global balance.

  16. Global view on radiation protection in medicine

    Vano, E.

    2011-01-01

    When planning good management of ionising radiation in medicine, key factors such as ensuring that health professionals work together and convincing them that radiation protection (RP) represents a substantial part of the quality management system in their clinical practice are of utmost importance. The United Nations Scientific Committee on the Effects of Atomic Radiation has decided that one of the thematic priorities will be medical radiation exposure of patients. The International Commission on Radiological Protection has recently updated the report on RP in medicine and continues to work on focused documents centred on specific areas where advice is needed. The roles of the International Atomic Energy Agency, World Health Organization and the European Commission, in the area of RP in medicine, are described in the present document. The industry, the standardisation organisations as well as many scientific and professional societies are also dedicating significant effort to radiation safety aspects in medicine. Some of the efforts and priorities contemplated in RP in medicine over the coming years are suggested. The best outcome will be accomplished when all the actors, i.e. medical doctors, other health professionals, regulators, health authorities and the industry manage to work together. (authors)

  17. Global Warming: The Balance of Evidence and Its Policy Implications

    Charles Keller

    2003-01-01

    Full Text Available Global warming and attendant climate change have been controversial for at least a decade. This is largely because of its societal implications. With the recent publication of the Third Assessment Report of the United Nations’ Intergovernmental Panel on Climate Change there has been renewed interest and controversy about how certain the scientific community is of its conclusions: that humans are influencing the climate and that global temperatures will continue to rise rapidly in this century. This review attempts to update what is known and in particular what advances have been made in the past 5 years or so. It does not attempt to be comprehensive. Rather it focuses on the most controversial issues, which are actually few in number. They are: 1-Is the surface temperature record accurate or is it biased by heat from cities, etc.? 2-Is that record significantly different from past warmings such as the Medieval Warming Period? 3-Is not the sun’s increasing activity the cause of most of the warming? 4-Can we model climate and predict its future, or is it just too complex and chaotic? 5-Are there any other changes in climate other than warming, and can they be attributed to the warming?Despite continued uncertainties, the review finds affirmative answers to these questions. Of particular interest are advances that seem to explain why satellites do not see as much warming as surface instruments, how we are getting a good idea of recent paleoclimates, and why the 20th century temperature record was so complex. It makes the point that in each area new information could come to light that would change our thinking on the quantitative magnitude and timing of anthropogenic warming, but it is unlikely to alter the basic conclusions.Finally, there is a very brief discussion of the societal policy response to the scientific message, and the author comments on his 2-year email discussions with many of the world’s most outspoken critics of the

  18. BALANCE

    Carmichael, H.

    1953-01-01

    A torsional-type analytical balance designed to arrive at its equilibrium point more quickly than previous balances is described. In order to prevent external heat sources creating air currents inside the balance casing that would reiard the attainment of equilibrium conditions, a relatively thick casing shaped as an inverted U is placed over the load support arms and the balance beam. This casing is of a metal of good thernnal conductivity characteristics, such as copper or aluminum, in order that heat applied to one portion of the balance is quickly conducted to all other sensitive areas, thus effectively preventing the fornnation of air currents caused by unequal heating of the balance.

  19. Tropical deforestation: balancing regional development demands and global environmental concerns

    Wood, A B [US Dept. of State, Washington, DC (USA)

    1990-01-01

    Over half of the world's tropical closed forests, which contain the greatest biodiversity, are found in just three countries: Brazil, Indonesia, and Zaire. Accelerated conversion of tropical forests is occurring because of several interlocking socio-economic and political factors: inequitable land distribution, entrenched rural poverty, and rapidly growing populations which push landless and near-landless peasants on to forest lands that are often infertile. If rates instead of absolute numbers are used to measure the severity of deforestation, Nigeria, Argentina, India, Thailand, Myanmar (Burma), Ecquador, and above all Ivory Coast stand out as countries facing an immediate deforestation crisis. Local management of forest resources, however, can be very contentious and complicated, with overlapping government agencies, competing economic interests, and ambiguous regulations. Without capital investment and entrepreneurial initiatives, residents of forest regions may have no alternative but to farm increasingly infertile soils. Non-governmental organizations, such as the World Wildlife Fund are playing leading roles in innovative debt-for-nature swaps and other forest conservation efforts. International development agencies, such as the World Bank, may play the leading role in conservation and reforestation efforts through their financial assistance programmes. The media, as a global information network, has become a powerful influence on the debate over deforestation. The Third World, bearing an increasingly heavy burden of payments to lending institutions that in 1988 surpassed 50 billion US dollars, will make a strong case that it cannot afford widespread forest conservation.

  20. Modifying a dynamic global vegetation model for simulating large spatial scale land surface water balances

    Tang, G.; Bartlein, P. J.

    2012-08-01

    Satellite-based data, such as vegetation type and fractional vegetation cover, are widely used in hydrologic models to prescribe the vegetation state in a study region. Dynamic global vegetation models (DGVM) simulate land surface hydrology. Incorporation of satellite-based data into a DGVM may enhance a model's ability to simulate land surface hydrology by reducing the task of model parameterization and providing distributed information on land characteristics. The objectives of this study are to (i) modify a DGVM for simulating land surface water balances; (ii) evaluate the modified model in simulating actual evapotranspiration (ET), soil moisture, and surface runoff at regional or watershed scales; and (iii) gain insight into the ability of both the original and modified model to simulate large spatial scale land surface hydrology. To achieve these objectives, we introduce the "LPJ-hydrology" (LH) model which incorporates satellite-based data into the Lund-Potsdam-Jena (LPJ) DGVM. To evaluate the model we ran LH using historical (1981-2006) climate data and satellite-based land covers at 2.5 arc-min grid cells for the conterminous US and for the entire world using coarser climate and land cover data. We evaluated the simulated ET, soil moisture, and surface runoff using a set of observed or simulated data at different spatial scales. Our results demonstrate that spatial patterns of LH-simulated annual ET and surface runoff are in accordance with previously published data for the US; LH-modeled monthly stream flow for 12 major rivers in the US was consistent with observed values respectively during the years 1981-2006 (R2 > 0.46, p 0.52). The modeled mean annual discharges for 10 major rivers worldwide also agreed well (differences day method for snowmelt computation, the addition of the solar radiation effect on snowmelt enabled LH to better simulate monthly stream flow in winter and early spring for rivers located at mid-to-high latitudes. In addition, LH

  1. Global levels of radiation exposure: Latest international findings

    Gonzalez, A.J.

    1993-01-01

    The radiation exposure of the world's population has recently been reviewed by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). UNSCEAR has reconfirmed that the normal operation of all peaceful nuclear installations contributes insignificantly to the global exposure to radiation. Even taking into account all the nuclear accidents to date (including Chernobyl), the additional exposure would be equivalent to only about 20 days of natural exposure. Military uses of nuclear energy have committed the world to most of the radiation exposure caused by human activities

  2. Some results of radiative balance in atmospheres with clouds

    Anduckia Avila, Juan Carlos; Pelkowski, Joaquin

    2000-01-01

    Vertical profiles of temperature for a semi grey three-Layer atmosphere are established using a radiative equilibrium condition. The approximation contains the greenhouse effect, scattering by clouds in one direction and isotropic diffuse reflection at the planet's surface. Absorption of short- wave radiation is also considered in one of the three layers. Similar models are contained therein

  3. New Temperature-based Models for Predicting Global Solar Radiation

    Hassan, Gasser E.; Youssef, M. Elsayed; Mohamed, Zahraa E.; Ali, Mohamed A.; Hanafy, Ahmed A.

    2016-01-01

    Highlights: • New temperature-based models for estimating solar radiation are investigated. • The models are validated against 20-years measured data of global solar radiation. • The new temperature-based model shows the best performance for coastal sites. • The new temperature-based model is more accurate than the sunshine-based models. • The new model is highly applicable with weather temperature forecast techniques. - Abstract: This study presents new ambient-temperature-based models for estimating global solar radiation as alternatives to the widely used sunshine-based models owing to the unavailability of sunshine data at all locations around the world. Seventeen new temperature-based models are established, validated and compared with other three models proposed in the literature (the Annandale, Allen and Goodin models) to estimate the monthly average daily global solar radiation on a horizontal surface. These models are developed using a 20-year measured dataset of global solar radiation for the case study location (Lat. 30°51′N and long. 29°34′E), and then, the general formulae of the newly suggested models are examined for ten different locations around Egypt. Moreover, the local formulae for the models are established and validated for two coastal locations where the general formulae give inaccurate predictions. Mostly common statistical errors are utilized to evaluate the performance of these models and identify the most accurate model. The obtained results show that the local formula for the most accurate new model provides good predictions for global solar radiation at different locations, especially at coastal sites. Moreover, the local and general formulas of the most accurate temperature-based model also perform better than the two most accurate sunshine-based models from the literature. The quick and accurate estimations of the global solar radiation using this approach can be employed in the design and evaluation of performance for

  4. Contrasting regional versus global radiative forcing by megacity pollution emissions

    Dang, H.; Unger, N.

    2015-10-01

    We assess the regional and global integrated radiative forcing on 20- and 100-year time horizons caused by a one-year pulse of present day pollution emissions from 10 megacity areas: Los Angeles, Mexico City, New York City, Sao Paulo, Lagos, Cairo, New Delhi, Beijing, Shanghai and Manila. The assessment includes well-mixed greenhouse gases: carbon dioxide (CO2), nitrous oxide (N2O), methane (CH4); and short-lived climate forcers: tropospheric ozone (O3) and fine mode aerosol particles (sulfate, nitrate, black carbon, primary and secondary organic aerosol). All megacities contribute net global warming on both time horizons. Most of the 10 megacity areas exert a net negative effect on their own regional radiation budget that is 10-100 times larger in magnitude than their global radiative effects. Of the cities examined, Beijing, New Delhi, Shanghai and New York contribute most to global warming with values ranging from +0.03 to 0.05 Wm-2yr on short timescales and +0.07-0.10 Wm-2yr on long timescales. Regional net 20-year radiative effects are largest for Mexico City (-0.84 Wm-2yr) and Beijing (-0.78 Wm-2yr). Megacity reduction of non-CH4 O3 precursors to improve air quality offers zero co-benefits to global climate. Megacity reduction of aerosols to improve air quality offers co-benefits to the regional radiative budget but minimal or no co-benefits to global climate with the exception of black carbon reductions in a few cities, especially Beijing and New Delhi. Results suggest that air pollution and global climate change mitigation can be treated as separate environmental issues in policy at the megacity level with the exception of CH4 action. Individual megacity reduction of CO2 and CH4 emissions can mitigate global warming and therefore offers climate safety improvements to the entire planet.

  5. Balancing requirements for radioactive waste management and radiation protection

    Lafuma, J.; Lefevre, J.

    1985-01-01

    The authors recall the principles of radiation protection and their application to radioactive waste management. The dose limitation system applies to every stage in management. The accepted risk limits should be compared with the level of risk from other sources, particularly from natural radiation. The uncertainties associated with long-term estimates should not lead to unrealistic requirements. The optimum rules are to be obtained by discussion among those responsible for radiation protection, nuclear safety and radioactive waste management. Satisfactory, applicable rules can be worked out in the present state of the art [fr

  6. Well-balanced schemes for the Euler equations with gravitation: Conservative formulation using global fluxes

    Chertock, Alina; Cui, Shumo; Kurganov, Alexander; Özcan, Şeyma Nur; Tadmor, Eitan

    2018-04-01

    We develop a second-order well-balanced central-upwind scheme for the compressible Euler equations with gravitational source term. Here, we advocate a new paradigm based on a purely conservative reformulation of the equations using global fluxes. The proposed scheme is capable of exactly preserving steady-state solutions expressed in terms of a nonlocal equilibrium variable. A crucial step in the construction of the second-order scheme is a well-balanced piecewise linear reconstruction of equilibrium variables combined with a well-balanced central-upwind evolution in time, which is adapted to reduce the amount of numerical viscosity when the flow is at (near) steady-state regime. We show the performance of our newly developed central-upwind scheme and demonstrate importance of perfect balance between the fluxes and gravitational forces in a series of one- and two-dimensional examples.

  7. Spatiotemporal Variability of Earth's Radiation Balance Components from Russian Radiometer IKOR-M

    Cherviakov, M.

    2016-12-01

    The radiometer IKOR-M was created in National Research Saratov State University for satellite monitoring of the outgoing reflected short-wave radiation, which is one of the components of Earth's radiation budget. Such information can be used in different models of long-term weather forecasts, in researches of climate change trends and in calculation of absorbed solar radiation values and albedo of the Earth-atmosphere system. The IKOR-M product archive is available online at all times. A searchable catalogue of data products is continually updated and users may search and download data products via the Earth radiation balance components research laboratory website as soon as they become available. Two series of measurements from two different IKOR-M are available. The first radiometer had worked from October 2009 to August 2014 and second - from August 2014 to the present. Therefore, there is a period when both radiometers work at the same time. Top-of-atmosphere fluxes deduced from the "Meteor-M" No 1 measurement in August, 2014 show very good agreement with the fluxes determined from "Meteor-M" No 2. The scale relationship of the IKOR-M radiometers on "Meteor - M" No 1 and No 2 satellites found by comparing of the global distribution maps for monthly averaged albedo values. The seasonal and interannual variations of OSR, albedo and ASR were discussed. The variations between SW radiation budget components seem to be within observational uncertainty and natural variability governed by cloudiness, water vapor and aerosol variations. It was assessed spatial and temporal variations of albedo and the absorbed solar radiation over different regions. Latitudinal distributions of albedo and ASR were estimated in more detail. Meridional cross sections over oceans and land were used separately for this estimation. It was shown that the albedo and ASR data received from the radiometer IKOR-M can be used to detect El Nino in the Pacific Ocean. The reported study was funded by

  8. Global solar radiation in Trieste (Italy)

    Anane-Fenin, K.

    1986-04-01

    Global irradiation data recorded at Trieste (CNR - Istituto Talassografico di Trieste) during 11-year period are grouped into ''summer'' and ''winter'' periods and are compared with values generated from seven different models and empirical correlations proposed by earlier investigations. Climatological parameters like sunshine duration, relative humidity, cloud cover and maximum air temperature are the models input. The calculated values obtained from correlations according to Angstrom and Black give better agreement with measured data in summer. Agreements are within +-3% and +-4%. In winter a quadratic equation is in better agreement with measured values. Agreement is within +7%

  9. Global warming 2007. An update to global warming: the balance of evidence and its policy implications.

    Keller, Charles F

    2007-03-09

    -induced warming that needs to be considered carefully. A final topic touched on briefly here is the new understanding of the phenomenon called "global dimming." Several sets of observations of the sun's total radiation at the surface have shown that there has been a reduction in sunlight reaching it. This has been related to the scattering of sunlight by aerosols and has led to a better quantification of the possibility that cleaning up our atmospheric pollution will lead to greater global warming. Adding all these advances together, there is a growing consensus that the 21st century will indeed see some 2 degrees C (3.5 degrees F) or more in additional warming. This is corroborated in the new IPCC Assessment, an early release of which is touched on very briefly here.

  10. Global crystallographic textures obtained by neutron and synchrotron radiation

    Brokmeier, Heinz-Guenter

    2006-01-01

    Global crystallographic textures belong to the main characteristic parameters of engineering materials. The global crystallographic texture is always the average texture of a well-defined sample volume which is representative to solve practical engineering problems. Thus a beam having a high penetration power is needed available as neutron or high energetic X-ray radiation. Texture type and texture sharpness are of great importance for materials properties such as the deep drawing behaviour, one of the basic techniques in many industries. Advantages and disadvantages of both radiations make them complementary for measuring crystallographic textures in a wide range of materials

  11. Combined equations for estimating global solar radiation: Projection of radiation field over Japan under global warming conditions by statistical downscaling

    Iizumi, T.; Nishimori, M.; Yokozawa, M.

    2008-01-01

    For this study, we developed a new statistical model to estimate the daily accumulated global solar radiation on the earth's surface and used the model to generate a high-resolution climate change scenario of the radiation field in Japan. The statistical model mainly relies on precipitable water vapor calculated from air temperature and relative humidity on the surface to estimate seasonal changes in global solar radiation. On the other hand, to estimate daily radiation fluctuations, the model uses either a diurnal temperature range or relative humidity. The diurnal temperature range, calculated from the daily maximum and minimum temperatures, and relative humidity is a general output of most climate models, and pertinent observation data are comparatively easy to access. The statistical model performed well when estimating the monthly mean value, daily fluctuation statistics, and regional differences in the radiation field in Japan. To project the change in the radiation field for the years 2081 to 2100, we applied the statistical model to the climate change scenario of a high-resolution Regional Climate Model with a 20-km mesh size (RCM20) developed at the Meteorological Research Institute based on the Special Report for Emission Scenario (SRES)-A2. The projected change shows the following tendency: global solar radiation will increase in the warm season and decrease in the cool season in many areas of Japan, indicating that global warming may cause changes in the radiation field in Japan. The generated climate change scenario for the radiation field is linked to long-term and short-term changes in air temperature and relative humidity obtained from the RCM20 and, consequently, is expected to complement the RCM20 datasets for an impact assessment study in the agricultural sector

  12. Global modeling of land water and energy balances. Part III: Interannual variability

    Shmakin, A.B.; Milly, P.C.D.; Dunne, K.A.

    2002-01-01

    The Land Dynamics (LaD) model is tested by comparison with observations of interannual variations in discharge from 44 large river basins for which relatively accurate time series of monthly precipitation (a primary model input) have recently been computed. When results are pooled across all basins, the model explains 67% of the interannual variance of annual runoff ratio anomalies (i.e., anomalies of annual discharge volume, normalized by long-term mean precipitation volume). The new estimates of basin precipitation appear to offer an improvement over those from a state-of-the-art analysis of global precipitation (the Climate Prediction Center Merged Analysis of Precipitation, CMAP), judging from comparisons of parallel model runs and of analyses of precipitation-discharge correlations. When the new precipitation estimates are used, the performance of the LaD model is comparable to, but not significantly better than, that of a simple, semiempirical water-balance relation that uses only annual totals of surface net radiation and precipitation. This implies that the LaD simulations of interannual runoff variability do not benefit substantially from information on geographical variability of land parameters or seasonal structure of interannual variability of precipitation. The aforementioned analyses necessitated the development of a method for downscaling of long-term monthly precipitation data to the relatively short timescales necessary for running the model. The method merges the long-term data with a reference dataset of 1-yr duration, having high temporal resolution. The success of the method, for the model and data considered here, was demonstrated in a series of model-model comparisons and in the comparisons of modeled and observed interannual variations of basin discharge.

  13. Radiation and global environment. Consideration for the influence on ecosystems

    Muramatsu, Yasuyuki; Doi, Masahiro; Yoshida, Satoshi

    2003-09-01

    This book is based on presentations at the National Institute of Radiological Sciences (NIRS) symposium of the same title held by the NIRS Research Center for Radiation Safety in December, 2002, is edited with somehow enlightening intention as well, and is composed from 6 parts of; 1. Reasons for concern for influence on ecosystems, 2. Behavior of substances in ecosystems, 3. Changes of global environments and life, 4. Various environmental stresses and living/eco-systems, 5. New development of evaluation studies on radiation effects, and 6. For the radiation protection of environments. The 1st part involves 3 chapters concerning studies on effects on ecosystems and radiation protection of environments; 2nd part, 4 chapters concerning behavior of radioactive and/or stable cesium and iodine in forest and environmental microorganisms, and behavior and effects of acidic substances; 3rd part, 2 chapters concerning terrestrial history and evolution/adaptation of livings; 4th part, 5 chapters concerning radiation stress, active oxygen, radiodurance/radio-resistant microorganisms, ultraviolet, and environmental hormones; 5th part, 6 chapters concerning effects on cells of environmental toxic substance and radiation, environmental stress evaluation by DNA micro-array, effects on taxis, use of microcosm, simulation of computational model ecosystem, and aquatic ecosystems; 6th part, 5 chapters concerning environmental radioecology, safety measures in high-level radioactive waste disposal under the ground, radiation protection of environments from radiation biology aspect, effects of chemicals, and aspect and strategy for radiation effects on environments. (N.I.)

  14. Global DNA methylation responses to low dose radiation exposure

    Newman, M.R.; Ormsby, R.J.; Blyth, B.J.; Sykes, P.J.; Bezak, E.

    2011-01-01

    Full text: High radiation doses cause breaks in the DNA which are considered the critical lesions in initiation of radiation-induced cancer. However, at very low radiation doses relevant for the general public, the induction of such breaks will be rare, and other changes to the DNA such as DNA methylation which affects gene expression may playa role in radiation responses. We are studying global DNA methylation after low dose radiation exposure to determine if low dose radiation has short- and/or long-term effects on chromatin structure. We developed a sensitive high resolution melt assay to measure the levels of DNA methylation across the mouse genome by analysing a stretch of DNA sequence within Long Interspersed Nuclear Elements-I (LINE I) that comprise a very large proportion of the mouse and human genomes. Our initial results suggest no significant short-term or longterm) changes in global NA methylation after low dose whole-body X-radiation of 10 J1Gyor 10 mGy, with a significant transient increase in NA methylation observed I day after a high dose of I Gy. If the low radiation doses tested are inducing changes in bal DNA methylation, these would appear to be smaller than the variation observed between the sexes and following the general stress of the sham-irradiation procedure itself. This research was funded by the Low Dose Radiation Research Program, Biological and Environmental Research, US DOE, Grant DE-FG02-05ER64104 and MN is the recipient of the FMCF/BHP Dose Radiation Research Scholarship.

  15. A review of the role of temperate forests in the global CO2 balance

    Musselman, R.C.; Fox, D.G.

    1991-01-01

    The role of temperate forests in the global carbon balance is difficult to determine because many uncertainties exist in the data, and many assumptions must be made in these determinations. Still, there is little doubt that increases in atmospheric CO 2 and global warming would have major effects on temperate forest ecosystems. Increases in atmospheric CO 2 may result in increases in photosynthesis, changes in water and nitrogen use efficiency, and changes in carbon allocation. Indirect effects of changes in global carbon balance on regional climate and on microenvironmental conditions, particularly temperature and moisture, may be more important then direct effects of increased CO 2 on vegetation. Increased incidence of forest perturbations might also be expected. The evidence suggests that conditions favorable to forest growth and development may exist in the northern latitudes, while southern latitude forests may undergo drought stress. Current harvest of temperate and world forests contributes substantial amounts of carbon to the atmosphere, possibly as much as 3 gigatons (Gt) per year. Return of this carbon to forest storage may require decades. Forest managers should be aware of the global as well as local impact their management decisions will have on the atmospheric carbon balance of the ecosystems they oversee

  16. Global radiative effects of solid fuel cookstove aerosol emissions

    Huang, Yaoxian; Unger, Nadine; Storelvmo, Trude; Harper, Kandice; Zheng, Yiqi; Heyes, Chris

    2018-04-01

    We apply the NCAR CAM5-Chem global aerosol-climate model to quantify the net global radiative effects of black and organic carbon aerosols from global and Indian solid fuel cookstove emissions for the year 2010. Our assessment accounts for the direct radiative effects, changes to cloud albedo and lifetime (aerosol indirect effect, AIE), impacts on clouds via the vertical temperature profile (semi-direct effect, SDE) and changes in the surface albedo of snow and ice (surface albedo effect). In addition, we provide the first estimate of household solid fuel black carbon emission effects on ice clouds. Anthropogenic emissions are from the IIASA GAINS ECLIPSE V5a inventory. A global dataset of black carbon (BC) and organic aerosol (OA) measurements from surface sites and aerosol optical depth (AOD) from AERONET is used to evaluate the model skill. Compared with observations, the model successfully reproduces the spatial patterns of atmospheric BC and OA concentrations, and agrees with measurements to within a factor of 2. Globally, the simulated AOD agrees well with observations, with a normalized mean bias close to zero. However, the model tends to underestimate AOD over India and China by ˜ 19 ± 4 % but overestimate it over Africa by ˜ 25 ± 11 % (± represents modeled temporal standard deviations for n = 5 run years). Without BC serving as ice nuclei (IN), global and Indian solid fuel cookstove aerosol emissions have net global cooling radiative effects of -141 ± 4 mW m-2 and -12 ± 4 mW m-2, respectively (± represents modeled temporal standard deviations for n = 5 run years). The net radiative impacts are dominated by the AIE and SDE mechanisms, which originate from enhanced cloud condensation nuclei concentrations for the formation of liquid and mixed-phase clouds, and a suppression of convective transport of water vapor from the lower troposphere to the upper troposphere/lower stratosphere that in turn leads to reduced ice cloud formation. When BC is allowed

  17. Global Solar Radiation in Spain from Satellite Images

    Ramirez, L.; Mora, L.; Sidrach de Cardona, M.; Navarro, A. A.; Varela, M.; Cruz, M. de la

    2003-01-01

    In the context of the present work a series of algorithms of calculation of the solar radiation from satellite images has been developed. These models, have been applied to three years of images of the Meteosat satellite and the results of the treatment have been extrapolated to long term. For the development of the models of solar radiation registered in ground stations have been used, corresponding all of them to localities of peninsular Spain and the Balearic ones. The maximum periods of data available have been used, supposing in most of the cases periods of between 6 and 9 years. From the results has a year type of images of global solar radiation on horizontal surface. The original resolution of the image of 7x7 km in the study latitudes, has been reevaluated to 5x5 km. This supposes to have a value of the typical radiation for every day of the year, each 5x5 km in the study territory. This information, supposes an important advance as far as the knowledge of the space distribution of the radiation solar, impossible to reach about alternative methods. Doubtlessly, the precision of the provided values is not comparable with pyrano metric measures in a concrete locality, but it provides a very valid indicator in places in which it is not had previous information. In addition to the radiation maps, tables of the global solar radiation have been prepared on different inclinations, from the global radiation on horizontal surface calculated for every day of the year and in each pixel of the image. (Author) 24 refs

  18. Solar radiation and energy balance in polyethylene covered greenhouse; Balancos de radiacao solar e de energia em estufa com cobertura de polietileno

    Frisina, Valeria de Almeida; Escobedo, Joao Francisco [UNESP, Botucatu, SP (Brazil). Faculdade de Ciencias Agronomicas. Dept. de Ciencias Ambientais

    1998-07-01

    The objective of this paper is describe the radiation and energy balance, during the lettuce (Lactuca sativa, L, var Veronica) crop cycle inside a polyethylene greenhouse. The radiation and energy balance was made inside of a tunnel greenhouse with polyethylene cover (100 {mu} m) and in an external area, both area with 35 m{sup 2}. Global (R{sub G}), reflected (R{sub r}) and net radiation (SR), soil heat flux and air temperature (dry and humid) were measured during crop cycle, in this two environment. In the data acquisition it was utilized a DATALOGGER, which operated at 1 Hz frequency, storing 5 minutes averages. The global and reflected radiations (MJ/m{sup 2}) allowed the verification that the average transmission of global radiation (R-G{sub in}/R{sub Gex}) was almost constant, near 79,59% while the average ratio of reflected radiation (R{sub rin}/R{sub rex}) was 69,21% with 8,47% standard-deviation. The short-wave radiation average (SRoc) was bigger in the external area. The normalized relation (SR/R{sub G}) was bigger in the external area, about 12%, when the green culture covered (SRol) was bigger outside, about 50%. The energy balance, estimated in terms of vertical fluxes, showed that, for the external area, in average, 83,07% of total net radiation was converted in latent heat evaporation; 18% in soil heat flux and 9,96% in sensible heat, while, inside of the greenhouse, 58,71% of total net radiation was converted in latent heat evaporation:; 42,68% in sensible heat and 28,79% in soil heat flux. (author)

  19. Empirical Models for the Estimation of Global Solar Radiation in ...

    Empirical Models for the Estimation of Global Solar Radiation in Yola, Nigeria. ... and average daily wind speed (WS) for the interval of three years (2010 – 2012) measured using various instruments for Yola of recorded data collected from the Center for Atmospheric Research (CAR), Anyigba are presented and analyzed.

  20. Radiation Ethics in a Globalized World

    Zoelzer, Friedo

    2013-01-01

    The presentation focused on implications to the ethics in RP, in a world more and more globalized and it challenges the present status of the moral philosophy underlying the ICRP recommendations, which appears to be preferentially based on western ethics. After presenting evident data showing that the center of gravity for existing and new nuclear plants is more and more toward far east populated countries, Friedo Zolzer asked himself if there is something like a 'common morality' to approach moral questions from very different cultural perspectives. Reference was made to the studies of Beauchamp and Childress with their identification of four principles and their claim that 'all persons committed to morality' would agree with their four principles. Common morality, for the author, cannot be defined via a 'Universal poll', but by studying cultures and religions practiced by the different populations in the past ages. He stated the need to develop common morality into 'cross cultural ethics' and the presentation went on by finding a relationship between the three RP principles (Justification, Optimization, Limitation) with the four principles of biomedical ethics (as part of the common morality). The lecturer then asked himself if the common morality can be of help in cases where the three RP principles are not directly applicable and after discussing three different cases, he concluded that common morality can provide us with additional criteria for certain problems not covered by the main RP principles. This approach, open to new different cultural backgrounds, seems to give a fresh inside to some problems, which cannot be addressed only on the basis of the current mix of utilitarian and deontological approaches in RP

  1. A modified Wheeler cap method for radiation efficiency measurement of balanced electrically small antennas

    Zhang, Jiaying; Pivnenko, Sergey; Breinbjerg, Olav

    2010-01-01

    , but not for balanced antennas like loops or dipoles. In this paper, a modified Wheeler cap method is proposed for the radiation efficiency measurement of balanced electrically small antennas and a three-port network model of the Wheeler cap measurement is introduced. The advantage of the modified method...... is that it is wideband, thus does not require any balun, and both the antenna input impedance and radiation efficiency can be obtained. An electrically small loop antenna and a wideband dipole were simulated and measured according to the proposed method and the results of measurements and simulations are presented...

  2. The balanced development of basic education in the context of globalization

    Sun Qi-lin; Kong Kai

    2006-01-01

    Basic education is not only an essential means for eliminating stratification and differences in society but also one of the main reasons for the enlargement of the gap between the rich and the poor.Because it faces pressure in the context of globalization,a balanced development of basic education would be a good way to relieve this pressure.This paper summarizes the international experience of balanced development of basic education in five aspects:policies and laws,educational funds,teacher resources,disadvantaged groups and conditions for running a school.On the basis of these,the authors put forward relevant suggestions concerning the balanced development of basic education in China.

  3. Evaluation of globally available precipitation data products as input for water balance models

    Lebrenz, H.; Bárdossy, A.

    2009-04-01

    Subject of this study is the evaluation of globally available precipitation data products, which are intended to be used as input variables for water balance models in ungauged basins. The selected data sources are a) the Global Precipitation Climatology Centre (GPCC), b) the Global Precipitation Climatology Project (GPCP) and c) the Climate Research Unit (CRU), resulting into twelve globally available data products. The data products imply different data bases, different derivation routines and varying resolutions in time and space. For validation purposes, the ground data from South Africa were screened on homogeneity and consistency by various tests and an outlier detection using multi-linear regression was performed. External Drift Kriging was subsequently applied on the ground data and the resulting precipitation arrays were compared to the different products with respect to quantity and variance.

  4. The future role of nuclear power in the global energy balance

    Semenov, B.A.; Guthrie, D.; Tatsuta, Y.

    1991-01-01

    A sound judgement on the role of nuclear power in the global energy balance within the time span of the next 30 years should logically be based on the consideration of at least a number of factors such as global trends in energy and electricity demand, practically available or estimated sources of supply, major requirements that these energy sources should meet, nuclear power's own potential, a realistic assessment of nuclear power's present status, and problems related to nuclear power. The conclusion of such an analysis is that nuclear power will retain, and may even enhance, its position as an important element in the world's energy supply mix

  5. Random balance designs for the estimation of first order global sensitivity indices

    Tarantola, S.; Gatelli, D.; Mara, T.A.

    2006-01-01

    We present two methods for the estimation of main effects in global sensitivity analysis. The methods adopt Satterthwaite's application of random balance designs in regression problems, and extend it to sensitivity analysis of model output for non-linear, non-additive models. Finite as well as infinite ranges for model input factors are allowed. The methods are easier to implement than any other method available for global sensitivity analysis, and reduce significantly the computational cost of the analysis. We test their performance on different test cases, including an international benchmark on safety assessment for nuclear waste disposal originally carried out by OECD/NEA

  6. Random balance designs for the estimation of first order global sensitivity indices

    Tarantola, S. [Joint Research Centre, European Commission, Institute of the Protection and Security of the Citizen, TP 361, Via E. Fermi 1, 21020 Ispra (Vatican City State, Holy See,) (Italy)]. E-mail: stefano.tarantola@jrc.it; Gatelli, D. [Joint Research Centre, European Commission, Institute of the Protection and Security of the Citizen, TP 361, Via E. Fermi 1, 21020 Ispra (VA) (Italy); Mara, T.A. [Laboratory of Industrial engineering, University of Reunion Island, BP 7151, 15 avenue Rene Cassin, 97 715 Saint-Denis (France)

    2006-06-15

    We present two methods for the estimation of main effects in global sensitivity analysis. The methods adopt Satterthwaite's application of random balance designs in regression problems, and extend it to sensitivity analysis of model output for non-linear, non-additive models. Finite as well as infinite ranges for model input factors are allowed. The methods are easier to implement than any other method available for global sensitivity analysis, and reduce significantly the computational cost of the analysis. We test their performance on different test cases, including an international benchmark on safety assessment for nuclear waste disposal originally carried out by OECD/NEA.

  7. Modifying a dynamic global vegetation model for simulating large spatial scale land surface water balances

    G. Tang

    2012-08-01

    Full Text Available Satellite-based data, such as vegetation type and fractional vegetation cover, are widely used in hydrologic models to prescribe the vegetation state in a study region. Dynamic global vegetation models (DGVM simulate land surface hydrology. Incorporation of satellite-based data into a DGVM may enhance a model's ability to simulate land surface hydrology by reducing the task of model parameterization and providing distributed information on land characteristics. The objectives of this study are to (i modify a DGVM for simulating land surface water balances; (ii evaluate the modified model in simulating actual evapotranspiration (ET, soil moisture, and surface runoff at regional or watershed scales; and (iii gain insight into the ability of both the original and modified model to simulate large spatial scale land surface hydrology. To achieve these objectives, we introduce the "LPJ-hydrology" (LH model which incorporates satellite-based data into the Lund-Potsdam-Jena (LPJ DGVM. To evaluate the model we ran LH using historical (1981–2006 climate data and satellite-based land covers at 2.5 arc-min grid cells for the conterminous US and for the entire world using coarser climate and land cover data. We evaluated the simulated ET, soil moisture, and surface runoff using a set of observed or simulated data at different spatial scales. Our results demonstrate that spatial patterns of LH-simulated annual ET and surface runoff are in accordance with previously published data for the US; LH-modeled monthly stream flow for 12 major rivers in the US was consistent with observed values respectively during the years 1981–2006 (R2 > 0.46, p < 0.01; Nash-Sutcliffe Coefficient > 0.52. The modeled mean annual discharges for 10 major rivers worldwide also agreed well (differences < 15% with observed values for these rivers. Compared to a degree-day method for snowmelt computation, the addition of the solar radiation effect on snowmelt

  8. The global resource balance table, an integrated table of energy, materials and the environment

    Tsuchiya, Haruki

    2013-01-01

    This paper introduces the Global Resource Balance Table (GRBT), which is an extension of the energy balance tables that expresses the relationships between energy, materials and the environment. The material division of the GRBT includes steel, cement, paper, wood and grain. In contrast, the environmental division of the GRBT includes oxygen, CO 2 and methane. The transaction division rows in the GRBT include production, conversion, end use and stock. Each cell of the GRBT contains the quantities of the respective resources that were generated or consumed. The relationships between the cells were constructed from the laws of conservation of the materials and energy. We constructed a GRBT for 2007 and discussed the increasing air temperature due to waste heat and the CO 2 equivalent from human breathing. The GRBT is a comprehensive integrated table that represents the resources that are consumed by human activities and is useful for energy and environmental studies. - Highlights: • We extended energy balance table and introduced Global Resource Balance Table. • It shows relationships between energy, materials and the environment. • The material division includes steel, cement, paper, wood and grain. • The environmental division includes oxygen, CO 2 and methane. • We discussed on waste heat and CO 2 emission by human breathing

  9. The Shifting Global Power Balance Equations and the Emerging Real ‘New World Order’

    Ovie-D’Leone, Alex Igho

    2010-01-01

    Expansion in globalization arising from increased interconnectivity and interdependence across the worldis causing a shift both in the focus of what now could determine the principal international powervariables and the criteria for power balancing calculus. One direct challenge to the status quo is theemergence on one hand of new state actors which are becoming more assertive, as well as some other newkey non-state actors now matching states seemingly one-on-one on the world stage in many sp...

  10. Using a biocultural approach to examine migration/globalization, diet quality, and energy balance.

    Himmelgreen, David A; Cantor, Allison; Arias, Sara; Romero Daza, Nancy

    2014-07-01

    The aim of this paper is to examine the role and impact that globalization and migration (e.g., intra-/intercontinental, urban/rural, and circular) have had on diet patterns, diet quality, and energy balance as reported on in the literature during the last 20 years. Published literature from the fields of anthropology, public health, nutrition, and other disciplines (e.g., economics) was collected and reviewed. In addition, case studies from the authors' own research are presented in order to elaborate on key points and dietary trends identified in the literature. While this review is not intended to be comprehensive, the findings suggest that the effects of migration and globalization on diet quality and energy balance are neither lineal nor direct, and that the role of social and physical environments, culture, social organization, and technology must be taken into account to better understand this relationship. Moreover, concepts such as acculturation and the nutrition transition do not necessarily explain or adequately describe all of the global processes that shape diet quality and energy balance. Theories from nutritional anthropology and critical bio-cultural medical anthropology are used to tease out some of these complex interrelationships. Copyright © 2014. Published by Elsevier Inc.

  11. Greenhouse gases and their impact on the radiation balance

    Eerme, K.

    1996-01-01

    In Estonian conditions, winter is believed to be the most sensitive season to climate change. The generation and movement of the determining climate air masses depend on the location of the polar front and on cyclo genetic activity over the Northen Atlantic. Specific effects include regional forcing by the water vapor, clouds and aerosols. In summer and fall, the climate forming air can have a different origin and can be more stable. Still, it is poorly understood how the local effects of atmospheric circulation depend on the global energy distribution pattern and its changes

  12. Global Particle Balance Measurements in DIII-D H-mode Discharges

    Unterberg, Ezekial A.; Allen, S.L.; Brooks, N.; Evans, T.E.; Leonard, A.W.; McLean, A.; Watkins, J.G.; Whyte, D.G.

    2011-01-01

    Experiments are performed on the DIII-D tokamak to determine the retention rate in an all graphite first-wall tokamak. A time-dependent particle balance analysis shows a majority of the fuel retention occurs during the initial Ohmic and L-mode phase of discharges, with peak fuel retention rates typically similar to 2 x 10(21) D/s. The retention rate can be zero within the experimental uncertainties (<3 x 10(20) D/s) during the later stationary phase of the discharge. In general, the retention inventory can decrease in the stationary phase by similar to 20-30% from the initial start-up phase of the discharge. Particle inventories determined as a function of time in the discharge, using a 'dynamic' particle balance analysis, agree with more accurate particle inventories directly measured after the discharge, termed 'static' particle balance. Similarly, low stationary retention rates are found in discharges with heating from neutral-beams, which injects particles, and from electron cyclotron waves, which does not inject particles. Detailed analysis of the static and dynamic balance methods provide an estimate of the DIII-D global co-deposition rate of <= 0.6-1.2 x 10(20) D/s. Dynamic particle balance is also performed on discharges with resonant magnetic perturbation ELM suppression and shows no additional retention during the ELM-suppressed phase of the discharge.

  13. An integrated artificial neural networks approach for predicting global radiation

    Azadeh, A.; Maghsoudi, A.; Sohrabkhani, S.

    2009-01-01

    This article presents an integrated artificial neural network (ANN) approach for predicting solar global radiation by climatological variables. The integrated ANN trains and tests data with multi layer perceptron (MLP) approach which has the lowest mean absolute percentage error (MAPE). The proposed approach is particularly useful for locations where no available measurement equipment. Also, it considers all related climatological and meteorological parameters as input variables. To show the applicability and superiority of the integrated ANN approach, monthly data were collected for 6 years (1995-2000) in six nominal cities in Iran. Separate model for each city is considered and the quantity of solar global radiation in each city is calculated. Furthermore an integrated ANN model has been introduced for prediction of solar global radiation. The acquired results of the integrated model have shown high accuracy of about 94%. The results of the integrated model have been compared with traditional angstrom's model to show its considerable accuracy. Therefore, the proposed approach can be used as an efficient tool for prediction of solar radiation in the remote and rural locations with no direct measurement equipment.

  14. Ultrasound power measurements of HITU transducer with a more stable radiation force balance

    Karaboece, B; Sadiko' lu, E; Bilgic, E, E-mail: baki.karaboce@ume.tubitak.gov.t [Tuebitak Ulusal Metroloji Enstituesue (UME), P.K. 54 41470 Gebze-Kocaeli (Turkey)

    2011-02-01

    A new radiation force balance (RFB) system was established at Turkish National Metrology Institute (UME) Ultrasonics Laboratory for High intensity therapeutic ultrasound (HITU) power measurements. The new system is highly stable at high power levels up to 500 Watts. The measurement system consists of a Plexiglas cylindrical balance arm, target mounting scale disks, conical reflecting and absorbing targets, adjustment nuts, and a hanging wire. Both of the two sides of balance were mounted similar size and weight targets. The equilibrium of the balance arm can be adjusted with nuts on screws located at both sides of the balance arm. Transducer was mounted to bottom of water tank. Absorbers in the bottom and the near walls of the tank were used for reflecting target case. Ultrasound power was applied to one scale of the balance where the reflecting/absorbing target was mounted and corresponding force was measured on the other scale of balance where was connected to a balance with a thin wire while the thin rest standing on a support. Ultrasound power of two HITU transducers at frequencies 0.93 MHz, 1.1 MHz and 3.3 MHz were measured with conventional and new system, the values were compared and uncertainty components were assessed in this paper.

  15. Ultrasound power measurements of HITU transducer with a more stable radiation force balance

    Karaboece, B; Sadiko'lu, E; Bilgic, E

    2011-01-01

    A new radiation force balance (RFB) system was established at Turkish National Metrology Institute (UME) Ultrasonics Laboratory for High intensity therapeutic ultrasound (HITU) power measurements. The new system is highly stable at high power levels up to 500 Watts. The measurement system consists of a Plexiglas cylindrical balance arm, target mounting scale disks, conical reflecting and absorbing targets, adjustment nuts, and a hanging wire. Both of the two sides of balance were mounted similar size and weight targets. The equilibrium of the balance arm can be adjusted with nuts on screws located at both sides of the balance arm. Transducer was mounted to bottom of water tank. Absorbers in the bottom and the near walls of the tank were used for reflecting target case. Ultrasound power was applied to one scale of the balance where the reflecting/absorbing target was mounted and corresponding force was measured on the other scale of balance where was connected to a balance with a thin wire while the thin rest standing on a support. Ultrasound power of two HITU transducers at frequencies 0.93 MHz, 1.1 MHz and 3.3 MHz were measured with conventional and new system, the values were compared and uncertainty components were assessed in this paper.

  16. World Energy Balance Outlook and OPEC Production Capacity: Implications for Global Oil Security

    Azadeh M. Rouhani

    2012-07-01

    Full Text Available The imbalance between energy resource availability, demand, and production capacity, coupled with inherent economic and environmental uncertainties make strategic energy resources planning, management, and decision-making a challenging process. In this paper, a descriptive approach has been taken to synthesize the world’s energy portfolio and the global energy balance outlook in order to provide insights into the role of Organization of Petroleum Exporting Countries (OPEC in maintaining “stability” and “balance” of the world’s energy market. This synthesis illustrates that in the absence of stringent policies, i.e., if historical trends of the global energy production and consumption hold into the future, it is unlikely that non-conventional liquid fuels and renewable energy sources will play a dominant role in meeting global energy demand by 2030. This should be a source of major global concern as the world may be unprepared for an ultimate shift to other energy sources when the imminent peak oil production is reached. OPEC’s potential to impact the supply and price of oil could enable this organization to act as a facilitator or a barrier for energy transition policies, and to play a key role in the global energy security through cooperative or non-cooperative strategies. It is argued that, as the global energy portfolio becomes more balanced in the long run, OPEC may change its typical high oil price strategies to drive the market prices to lower equilibria, making alternative energy sources less competitive. Alternatively, OPEC can contribute to a cooperative portfolio management approach to help mitigate the gradually emerging energy crisis and global warming, facilitating a less turbulent energy transition path while there is time.

  17. CO2 and solar radiation: cause of global warming?

    Bayona Gabriel; Garcia, Yuri C.; Sarmiento Heiner R

    2010-01-01

    A cause-effect relationship between global temperature as a climatic change indicator and some of the main forcing mechanisms (Atmospheric CO 2 concentration, solar radiation and volcanic activity) are analyzed in this paper through time series analysis for the 1610-1990 AD period comparing trends and variability for the frequency spectrums. Temperature seems to fit the CO 2 trend for the last century, but we found no cause-effect relationship for this interval. The frequency analysis shows a correlation between radiation and temperature for a period of 22 years. Volcanism presents an inverse relationship with temperature better seen at a decadal scale.

  18. Water balance creates a threshold in soil pH at the global scale

    Slessarev, E. W.; Lin, Y.; Bingham, N. L.; Johnson, J. E.; Dai, Y.; Schimel, J. P.; Chadwick, O. A.

    2016-12-01

    Soil pH regulates the capacity of soils to store and supply nutrients, and thus contributes substantially to controlling productivity in terrestrial ecosystems. However, soil pH is not an independent regulator of soil fertility—rather, it is ultimately controlled by environmental forcing. In particular, small changes in water balance cause a steep transition from alkaline to acid soils across natural climate gradients. Although the processes governing this threshold in soil pH are well understood, the threshold has not been quantified at the global scale, where the influence of climate may be confounded by the effects of topography and mineralogy. Here we evaluate the global relationship between water balance and soil pH by extracting a spatially random sample (n = 20,000) from an extensive compilation of 60,291 soil pH measurements. We show that there is an abrupt transition from alkaline to acid soil pH that occurs at the point where mean annual precipitation begins to exceed mean annual potential evapotranspiration. We evaluate deviations from this global pattern, showing that they may result from seasonality, climate history, erosion and mineralogy. These results demonstrate that climate creates a nonlinear pattern in soil solution chemistry at the global scale; they also reveal conditions under which soils maintain pH out of equilibrium with modern climate.

  19. Influence of inhomogeneous surface heat capacity on the estimation of radiative response coefficients in a two-zone energy balance model

    Park, Jungmin; Choi, Yong-Sang

    2018-04-01

    Observationally constrained values of the global radiative response coefficient are pivotal to assess the reliability of modeled climate feedbacks. A widely used approach is to measure transient global radiative imbalance related to surface temperature changes. However, in this approach, a potential error in the estimate of radiative response coefficients may arise from surface inhomogeneity in the climate system. We examined this issue theoretically using a simple two-zone energy balance model. Here, we dealt with the potential error by subtracting the prescribed radiative response coefficient from those calculated within the two-zone framework. Each zone was characterized by the different magnitude of the radiative response coefficient and the surface heat capacity, and the dynamical heat transport in the atmosphere between the zones was parameterized as a linear function of the temperature difference between the zones. Then, the model system was forced by randomly generated monthly varying forcing mimicking time-varying forcing like an observation. The repeated simulations showed that inhomogeneous surface heat capacity causes considerable miscalculation (down to -1.4 W m-2 K-1 equivalent to 31.3% of the prescribed value) in the global radiative response coefficient. Also, the dynamical heat transport reduced this miscalculation driven by inhomogeneity of surface heat capacity. Therefore, the estimation of radiative response coefficients using the surface temperature-radiation relation is appropriate for homogeneous surface areas least affected by the exterior.

  20. Applicability of empirical correlations for estimating global solar radiation

    Gopinathan, K.K.; Baholo, M.

    1987-01-01

    Three empirical models suggested by different investigators, for estimating monthly mean daily global radiation on a horizontal surface, are compared statistically to test their universal applicability. The models thus compared are those suggested by Rietveld, Glover and McCulloch and Gopinathan. The models are compared by calculating the root mean square error, mean bias error and mean relative percentage error values. The model suggested by Gopinathan yields the best results in terms of root mean square, mean bias and mean percentage errors. The model by Rietveld is the second best and the model by Glover and McCulloch comes at third place. However, the differences in the magnitude of errors among the three models are very small and all the three models can be considered to be accurate for global radiation estimation for any location in the world

  1. Global solar radiation estimation in Lavras region, Minas Gerais

    Dantas, A.A.A.; Carvalho, L.G. de; Ferreira, E.

    2003-01-01

    The objective of this work was the determination of the ''a'' and '' b'' constants of the Angstrom linear model in order to estimate the global solar radiation in Lavras, MG. The work was carried out in the Climatological Station of Lavras (ECP/INMET/UFLA), at the Federal University of Lavras, from December 2001 to November 2002, through insolation daily data and global solar radiation daily records. The ''a'' and '' b'' constants, that express the atmospheric transmitance, were obtained by regression analysis of those data. The obtained equation, Qg/Qt = 0,23 + 0,49 presented a determination coefficient of 0,89. The results are smaller than those suggested by the recommendations that uses the local latitude. According to the results, its possible to indicate the values of 0,23 and 0,49 to be used as the ''a'' and '' b'' constants on the Angstrom equation to estimate the global solar radiation in Lavras, MG. (author) [pt

  2. Radiation balances of melting snow covers at an open site in the Central Sierra Nevada, California

    Aguado, E.

    1985-01-01

    The radiation balances of melting snow packs for three seasons at an open site at the Central Sierra Snow Laboratory near Soda Springs, California were examined. The snow covers were examples of below-normal, near-normal and much-above-normal water equivalents. Two of the snow covers melted under generally clear skies in late spring while the other melted under cloudier conditions and at a time when less extraterrestrial radiation was available. Moreover, the snow covers were of very different densities, thereby allowing examination of a possible relationship between that characteristic and albedo. No such relationship was observed. Despite the dissimilarities in the conditions under which melt occurred, the disposition of solar radiation was similar for the three melt seasons. Albedos and their rates of decline through the melt season were similar for the three seasons. Absorbed solar radiation and a cloudiness index were useful predictors for daily net radiation, accounting for 71% of the total variance. (author)

  3. Performance analysis of tracked panel according to predicted global radiation

    Chang, T.P.

    2009-01-01

    In this paper, the performance of a south facing single-axis tracked panel was analyzed according to global radiation predicted by empirical model. Mathematic expressions appropriate for single-axis tracking system were derived to calculate the radiation on it. Instantaneous increments of solar energy collected by the tracked panel relative to fixed panel are illustrated. The validity of the empirical model to Taiwan area will also be examined with the actual irradiation data observed in Taipei. The results are summarized as follows: the gains made by the tracked panel relative to a fixed panel are between 20.0% and 33.9% for four specified days of year, between 20.9% and 33.2% for the four seasons and 27.6% over the entire year. For latitudes below 65 deg., the yearly optimal tilt angle of a fixed panel is close to 0.8 times latitude, the irradiation ratio of the tracked panel to the fixed panel is about 1.3, which are smaller than the corresponding values calculated from extraterrestrial radiation, suggesting us that the installation angle should be adjusted toward a flatter angle and that the gain of the tracked panel will reduce while it works in cloudy climate or in air pollution environment. Although the captured radiation increases with the maximal rotation angle of panel, but the benefit on the global radiation case is still not so good as that on extraterrestrial radiation case. The irradiation data observed is much less than the data predicted by the empirical model, however the trend of fitting curve to the observed data is somewhat in agreement with that to the predicted one; the yearly gain is 14.3% when a tracked panel is employed throughout the year.

  4. Global particle balance and wall recycling properties of long duration discharges on TRIAM-1M

    Sakamoto, M.; Yuno, M.; Itoh, S.

    2003-01-01

    The longest tokamak discharge with the duration of 11406 s (3 h 10 min) was achieved. The global particle balance has been investigated. In the longest discharge, the global balance between the particle absorption and release of the wall was achieved around t∼30 min and then the fueling was automatically stopped. After that the plasma density was maintained by the recycling flux alone until the end of the discharge. The maximum wall inventory is about 3.6 x 10 20 H at t ∼ 30 min but it is finally released from the wall at the end of the discharge. The global balance seems to be caused by the increase in the hydrogen release from the main chamber resulting from its temperature rise. Moreover, it has been observed a large difference between properties of wall recycling in the continuous gas feed case (i.e. static condition) and the additional gas puff case (i.e. dynamic condition). In the static condition, the effective particle confinement time increases almost linearly to about 10 s during the one-minute discharge. In the dynamic condition, the decay time of the electron density just after the gas puff, i.e. the effective particle confinement time, is 0.2 to 0.3 s during the one-minute discharge. The large difference was also reproduced in the longest discharge. It is considered that the enhanced wall pumping is caused by the increase in fluxes of the diffused ions and charge exchange neutrals due to the additional gas puff. (author)

  5. Bahrain and the global balance of power after the Arab spring

    Andersen, Lars Erslev

    2012-01-01

    The global balance of power is changing, and the role of the US as the only superpower is being challenged by emerging new powers and a still more powerful China. Nowhere is this more apparent than in the Persian Gulf. Two wars in Afghanistan and Iraq and continually rising debt have meant that the position of the US has declined. At the same time, Asian states are increasing their economic expansion in the Persian Gulf. Increasing political influence, including a bigger role in hard security...

  6. National innovation policy and global open innovation: Exploring balances, tradeoffs and complementarities

    Bloch, Carter Walter; Sverre, Herstad; Ebersberger, Bernd

    2010-01-01

    . We argue that the purpose of public research and innovation policy remains one of developing and sustaining territorial knowledge bases capable of growing and supporting internationally competitive industries. But the rules of the game have changed. Public policy now needs to carefully balance......The aim of this article is to suggest a framework for examining the way national policy mixes are responding to the challenges and opportunities of globally distributed knowledge networks, cross-sectoral technology flows and consequently open innovation processes occurring on an international scale...

  7. O Brasil na iniciativa BRIC: soft balancing numa ordem global em mudança?

    Flemes, Daniel

    2010-01-01

    As opções de política externa do Brasil são limitadas, tendo em conta os recursos materiais superiores das grandes potências establecidas. Soft balancing envolve estratégias institucionais, tais como a formação de coalizões ou ententes diplomáticas limitadas, como BRIC, para restringir o poder das grandes potências estabelecidas. Os países BRIC tinham constado dentre os precursores mais fortes de mudança da diplomacia mundial e por sua vez se beneficiam mais destas mudanças de poder global. D...

  8. Japan and the changing global balance of power: The view from the summit

    Dobson, H.

    2010-01-01

    This article explores Japan's relative decline and its responses to the changing global balance of power through a case study of one symptom of this shift: the rise of the G20 as the 'premier forum for international economic co-operation' at the expense of the G8. The G8 has traditionally held a significant position in Japan's international relations that appears to be undermined by the rise of the G20. Japan's responses to these developments reveal it to be a status quo power that is still c...

  9. Century-scale variability in global annual runoff examined using a water balance model

    McCabe, G.J.; Wolock, D.M.

    2011-01-01

    A monthly water balance model (WB model) is used with CRUTS2.1 monthly temperature and precipitation data to generate time series of monthly runoff for all land areas of the globe for the period 1905 through 2002. Even though annual precipitation accounts for most of the temporal and spatial variability in annual runoff, increases in temperature have had an increasingly negative effect on annual runoff after 1980. Although the effects of increasing temperature on runoff became more apparent after 1980, the relative magnitude of these effects are small compared to the effects of precipitation on global runoff. ?? 2010 Royal Meteorological Society.

  10. A Kalman Filter-Based Method for Reconstructing GMS-5 Global Solar Radiation by Introduction of In Situ Data

    Yong Wang

    2013-06-01

    Full Text Available Solar radiation is an important input for various land-surface energy balance models. Global solar radiation data retrieved from the Japanese Geostationary Meteorological Satellite 5 (GMS-5/Visible and Infrared Spin Scan Radiometer (VISSR has been widely used in recent years. However, due to the impact of clouds, aerosols, solar elevation angle and bidirectional reflection, spatial or temporal deficiencies often exist in solar radiation datasets that are derived from satellite remote sensing, which can seriously affect the accuracy of application models of land-surface energy balance. The goal of reconstructing radiation data is to simulate the seasonal variation patterns of solar radiation, using various statistical and numerical analysis methods to interpolate the missing observations and optimize the whole time-series dataset. In the current study, a reconstruction method based on data assimilation is proposed. Using a Kalman filter as the assimilation algorithm, the retrieved radiation values are corrected through the continuous introduction of local in-situ global solar radiation (GSR provided by the China Meteorological Data Sharing Service System (Daily radiation dataset_Version 3 which were collected from 122 radiation data collection stations over China. A complete and optimal set of time-series data is ultimately obtained. This method is applied and verified in China’s northern agricultural areas (humid regions, semi-humid regions and semi-arid regions in a warm temperate zone. The results show that the mean value and standard deviation of the reconstructed solar radiation data series are significantly improved, with greater consistency with ground-based observations than the series before reconstruction. The method implemented in this study provides a new solution for the time-series reconstruction of surface energy parameters, which can provide more reliable data for scientific research and regional renewable-energy planning.

  11. Local and global particle and power balance in large area capacitive discharges

    Cho, Suwon; Lieberman, M A

    2003-01-01

    Large area radio frequency (rf) capacitive discharges have attracted recent interest for materials etching and deposition on large area substrates. A distinguishing feature is that the radial distribution of the absorbed rf power in these discharges depends on the rf voltage across the plates, independent of the radial variation of the plasma density n(r). A reduced set of steady-state fluid equations has been used to investigate the radial variation of n and electron temperature T e . The derived equations are shown to be invariant with respect to pL and pR, where p is the pressure, L is the plate separation and R is the discharge radius, and can be further reduced to the equations of the usual global balance model when R ε , the energy relaxation length. In this limit, the ionization frequency and T e are essentially independent of radius and n can be approximately described by the usual radial profile of a zeroth-order Bessel function. When R≥λ ε , n and T e are predominantly determined by local particle and power balance, and the n and T e radial profiles are flat over most of the volume except near the radial boundary, where n falls and T e rises to account for the increased losses at the boundary. The scale length of the edge density variation in the local balance regime is shown to be proportional to the energy relaxation length

  12. Radiatively-driven winds: model improvements, ionization balance and the infared spectrum

    Castor, J.I.

    1979-01-01

    Recent improvements to theoretical stellar wind models and the results of empirical modelling of the ionization balance and the infrared continuum are discussed. The model of a wind driven by radiation pressure in spectral lines is improved by accounting for overlap of the driving lines, dependence of ionization balance on density, and stellar rotation. These effects produce a softer velocity law than that given by Castor, Abbott and Klein (1975). The ionization balance in zeta Puppis is shown to agree with that estimated for an optically thick wind at a gas temperature of 60,000 K. The ionization model is not unique. The infrared continuum of zeta Pup measured by Barlow and Cohen is fitted to a cool model with a linear rise of velocity with radius; this fit is also not unique. It is concluded that one should try to find a model that fits several kinds of evidence simultaneously. (Auth.)

  13. A new technology aimed at re-establishing a global sulphur supply/demand balance

    Slavens, A.F.; Jorgensen, C.; Ogg, D.

    2009-01-01

    The world's sulphur supply is mainly determined by involuntary production of elemental sulphur during the processing of oil and gas. As a result, sulphur supply is decoupled from demand, resulting in an imbalance between the two. For almost two decades, sulphur supply has exceeded demand, which has raised significant concerns for oil and gas producers such as where to store all of the excess sulphur, and how to transport a low-value commodity to market in an economically attractive fashion. Black and Veatch is involved in the development of a new technology called sulphur to energy process (STEP TM ) which has the potential to assist in balancing global sulphur supply and demand, as well as affording other benefits such as low-emission energy production. This paper presented the potential merits of the STEP as a means to reestablish a global sulphur supply/demand balance for the world trading market. It explored the other potential benefits that may result from the use of this new technology and compared STEP to other technologies and operating schemes that regulate sulphur supply. It was concluded that STEP has the potential to allow the processor to produce elemental sulphur when demand is high, or to provide safe and ecological disposal when demand is low, with the added benefits of energy recovery from the sulphur combustion process, and sour gas reservoir sweetening over time as sulphur dioxide reacts with hydrogen sulphide present in the reservoir. 13 refs., 3 tabs., 22 figs

  14. Estimation of clear sky hourly global solar radiation in Iraq

    Al-Jumaily, Kais J.; Al-Zuhairi, Munya F.; Mahdi, Zahraa S. [Department of Atmospheric Sciences, College of Science, Al-Mustansiriyah University, Baghdad (Iraq)

    2012-07-01

    The availability of hourly solar radiation data is very important for applications utilizing solar energy and for climate and environmental aspects. The aim of this work is to use a simple model for estimating hourly global solar radiation under clear sky condition in Iraq. Calculations were compared with measurements obtained from local station in Baghdad city and from Meteosat satellite data for different locations in Iraq. The statistical test methods of the mean bias error (MBE), root mean square error (RMSE) and t-test were used to evaluate the performance of the model. Results indicated that a fairly good agreement exists between calculated and measured values for all locations in Iraq. Since the model is independent of any meteorological variable, it would be of a practical use for rural areas where no meteorological data are available.

  15. Multidisciplinary approaches to radiation-balanced lasers (MARBLE): a MURI program by AFOSR (Conference Presentation)

    Sheik-Bahae, Mansoor

    2017-02-01

    An overview of the diverse research activities under the newly funded MURI project by AFOSR will be presented. The main goal is to advance the science of radiation-balanced lasers, also known as athermal lasers, in order to mitigate the thermal degradation of the high-power laser beams. The MARBLE project involves researchers from four universities and spans research activities in rare-earth doped crystals and fibers to semiconductor disc lasers.

  16. Impact of Precipitating Ice Hydrometeors on Longwave Radiative Effect Estimated by a Global Cloud-System Resolving Model

    Chen, Ying-Wen; Seiki, Tatsuya; Kodama, Chihiro; Satoh, Masaki; Noda, Akira T.

    2018-02-01

    Satellite observation and general circulation model (GCM) studies suggest that precipitating ice makes nonnegligible contributions to the radiation balance of the Earth. However, in most GCMs, precipitating ice is diagnosed and its radiative effects are not taken into account. Here we examine the longwave radiative impact of precipitating ice using a global nonhydrostatic atmospheric model with a double-moment cloud microphysics scheme. An off-line radiation model is employed to determine cloud radiative effects according to the amount and altitude of each type of ice hydrometeor. Results show that the snow radiative effect reaches 2 W m-2 in the tropics, which is about half the value estimated by previous studies. This effect is strongly dependent on the vertical separation of ice categories and is partially generated by differences in terminal velocities, which are not represented in GCMs with diagnostic precipitating ice. Results from sensitivity experiments that artificially change the categories and altitudes of precipitating ice show that the simulated longwave heating profile and longwave radiation field are sensitive to the treatment of precipitating ice in models. This study emphasizes the importance of incorporating appropriate treatments for the radiative effects of precipitating ice in cloud and radiation schemes in GCMs in order to capture the cloud radiative effects of upper level clouds.

  17. [Comparison of three daily global solar radiation models].

    Yang, Jin-Ming; Fan, Wen-Yi; Zhao, Ying-Hui

    2014-08-01

    Three daily global solar radiation estimation models ( Å-P model, Thornton-Running model and model provided by Liu Ke-qun et al.) were analyzed and compared using data of 13 weather stations from 1982 to 2012 from three northeastern provinces and eastern Inner Mongolia. After cross-validation analysis, the result showed that mean absolute error (MAE) for each model was 1.71, 2.83 and 1.68 MJ x m(-2) x d(-1) respectively, showing that Å-P model and model provided by Liu Ke-qun et al. which used percentage of sunshine had an advantage over Thornton-Running model which didn't use percentage of sunshine. Model provided by Liu Ke-qun et al. played a good effect on the situation of non-sunshine, and its MAE and bias percentage were 18.5% and 33.8% smaller than those of Å-P model, respectively. High precision results could be obtained by using the simple linear model of Å-P. Å-P model, Thornton-Running model and model provided by Liu Ke-qun et al. overvalued daily global solar radiation by 12.2%, 19.2% and 9.9% respectively. MAE for each station varied little with the spatial change of location, and annual MAE decreased with the advance of years. The reason for this might be that the change of observation accuracy caused by the replacement of radiation instrument in 1993. MAEs for rainy days, non-sunshine days and warm seasons of the three models were greater than those for days without rain, sunshine days and cold seasons respectively, showing that different methods should be used for different weather conditions on estimating solar radiation with meteorological elements.

  18. Global Horizontal Control Network of Shanghai Synchrotron Radiation Facility

    Yu Chenghao; Ke Ming; Du Hanwen; Yin Lixin; Zhao Zhentang; Dong Lan; Huang Kaixi

    2009-01-01

    As a national big scientific engineering, Shanghai Synchrotron Radiation Facility (SSRF) has rigid requirement to the components with sub-millimeter accuracy. In the process of survey and positioning global control network is a connecting link, which determines the position relationship between building and accelerator devices, and provides high accuracy datum to local control network. Within the designing process, building and devices are very restrict. While among observation, it's hard to be observed and abound with disadvantages. With continuous optimization and careful operation, super-high accuracy of 0.3 mm within 400 m circumference was achieved and slab's periodic movement could be seen through 3 times measurement. (authors)

  19. Frequency-independent radiation modes of interior sound radiation: Experimental study and global active control

    Hesse, C.; Papantoni, V.; Algermissen, S.; Monner, H. P.

    2017-08-01

    Active control of structural sound radiation is a promising technique to overcome the poor passive acoustic isolation performance of lightweight structures in the low-frequency region. Active structural acoustic control commonly aims at the suppression of the far-field radiated sound power. This paper is concerned with the active control of sound radiation into acoustic enclosures. Experimental results of a coupled rectangular plate-fluid system under stochastic excitation are presented. The amplitudes of the frequency-independent interior radiation modes are determined in real-time using a set of structural vibration sensors, for the purpose of estimating their contribution to the acoustic potential energy in the enclosure. This approach is validated by acoustic measurements inside the cavity. Utilizing a feedback control approach, a broadband reduction of the global acoustic response inside the enclosure is achieved.

  20. Current and future impacts of ultraviolet radiation on the terrestrial carbon balance

    W. Kolby SMITH; Wei GAO; Heidi STELTZER

    2009-01-01

    One of the most documented effects of human activity on our environment is the reduction of stratospheric ozone resulting in an increase of biologically harmful ultraviolet (UV) radiation. In a less predictable manner, UV radiation incident at the surface of the earth is expected to be further modified in the future as a result of altered cloud condition, atmospheric aerosol concentration, and snow cover. Although UV radiation comprises only a small fraction of the total solar radiation that is incident at the earth's surface, it has the greatest energy per unit wavelength and, thus, the greatest potential to damage the biosphere. Recent investigations have highlighted numerous ways that UV radiation could potentially affect a variety of ecological processes, including nutrient cycling and the terrestrial carbon cycle. The objectives of the following literature review are to summarize and synthesize the available information relevant to the effects of UV radiation and other climate change factors on the terrestrial carbon balance in an effort to highlight current gaps in knowledge and future research directions for UV radiation research.

  1. Incorrectly Interpreting the Carbon Mass Balance Technique Leads to Biased Emissions Estimates from Global Vegetation Fires

    Surawski, N. C.; Sullivan, A. L.; Roxburgh, S. H.; Meyer, M.; Polglase, P. J.

    2016-12-01

    Vegetation fires are a complex phenomenon and have a range of global impacts including influences on climate. Even though fire is a necessary disturbance for the maintenance of some ecosystems, a range of anthropogenically deleterious consequences are associated with it, such as damage to assets and infrastructure, loss of life, as well as degradation to air quality leading to negative impacts on human health. Estimating carbon emissions from fire relies on a carbon mass balance technique which has evolved with two different interpretations in the fire emissions community. Databases reporting global fire emissions estimates use an approach based on `consumed biomass' which is an approximation to the biogeochemically correct `burnt carbon' approach. Disagreement between the two methods occurs because the `consumed biomass' accounting technique assumes that all burnt carbon is volatilized and emitted. By undertaking a global review of the fraction of burnt carbon emitted to the atmosphere, we show that the `consumed biomass' accounting approach overestimates global carbon emissions by 4.0%, or 100 Teragrams, annually. The required correction is significant and represents 9% of the net global forest carbon sink estimated annually. To correctly partition burnt carbon between that emitted to the atmosphere and that remaining as a post-fire residue requires the post-burn carbon content to be estimated, which is quite often not undertaken in atmospheric emissions studies. To broaden our understanding of ecosystem carbon fluxes, it is recommended that the change in carbon content associated with burnt residues be accounted for. Apart from correctly partitioning burnt carbon between the emitted and residue pools, it enables an accounting approach which can assess the efficacy of fire management operations targeted at sequestering carbon from fire. These findings are particularly relevant for the second commitment period for the Kyoto protocol, since improved landscape fire

  2. A kind of balance between exploitation and exploration on kriging for global optimization of expensive functions

    Dong, Huachao; Song, Baowei; Wang, Peng; Huang, Shuai

    2015-01-01

    In this paper, a novel kriging-based algorithm for global optimization of computationally expensive black-box functions is presented. This algorithm utilizes a multi-start approach to find all of the local optimal values of the surrogate model and performs searches within the neighboring area around these local optimal positions. Compared with traditional surrogate-based global optimization method, this algorithm provides another kind of balance between exploitation and exploration on kriging-based model. In addition, a new search strategy is proposed and coupled into this optimization process. The local search strategy employs a kind of improved 'Minimizing the predictor' method, which dynamically adjusts search direction and radius until finds the optimal value. Furthermore, the global search strategy utilizes the advantage of kriging-based model in predicting unexplored regions to guarantee the reliability of the algorithm. Finally, experiments on 13 test functions with six algorithms are set up and the results show that the proposed algorithm is very promising.

  3. Global aerosol transport and consequences for the radiation budget

    Newiger, M.; Grassl, H.; Schussel, P.; Rehkopf, J.

    1984-01-01

    Man's activities may influence global climate by changing the atmospheric composition and surface characteristics and by waste heat. Most prominent within this discussion is the increase or decrease of radiatively active trace gases like CO/sub 2/, N/sub 2/O, O/sub 3/, and others. The general opinion is converging towards a greenhouse effect as a combined action of all trace gases, whose exact magnitude is uncertain mainly because of the unknown reaction of water cycle. The aim of our global 2-D (resolving latitude and height) aerosol transport model is the calculation of aerosol particle number density profiles as a function of latitude for present natural plus anthropogenic emissions. The aerosol transport model uses prescribed meridonal circulation, diffusivity factors and cloud climatology for January as well as July. All these latitude and height dependent input parameters were taken from well known sources. The fixed climatology excludes the feedback of aerosol particle parameter changes on mean circulation. However, the radiative parameters of six clouds types are modified, although they possess by adoption of the Telegadas and London (1954) cloud climatology prescribed amount and height. The inclusion of the feedback on mean circulation seems premature at present. Adding particles either accounting for natural emissions or natural anthropogenic emission and removing particles by all known sinks outside and within clouds gives us - for the stationary state - vertical profiles of aerosol number density in three sizes classes as a function of latitude. These profiles in turn are input for radiation flux calculations in clear and cloudy areas in order to assess net flux changes caused by the present aerosol load in comparison to a scenario without anthropogenic emissions. The net flux changes finally are compared to those calculated for increased CO/sub 2/ levels

  4. Clouds-radiation interactions in a general circulation model - Impact upon the planetary radiation balance

    Smith, Laura D.; Vonder Haar, Thomas H.

    1991-01-01

    Simultaneously conducted observations of the earth radiation budget and the cloud amount estimates, taken during the June 1979 - May 1980 Nimbus 7 mission were used to show interactions between the cloud amount and raidation and to verify a long-term climate simulation obtained with the latest version of the NCAR Community Climate Model (CCM). The parameterization of the radiative, dynamic, and thermodynamic processes produced the mean radiation and cloud quantities that were in reasonable agreement with satellite observations, but at the expense of simulating their short-term fluctuations. The results support the assumption that the inclusion of the cloud liquid water (ice) variable would be the best mean to reduce the blinking of clouds in NCAR CCM.

  5. Solving the radiation diffusion and energy balance equations using pseudo-transient continuation

    Shestakov, A.I.; Greenough, J.A.; Howell, L.H.

    2005-01-01

    We develop a scheme for the system coupling the radiation diffusion and matter energy balance equations. The method is based on fully implicit, first-order, backward Euler differencing; Picard-Newton iterations solve the nonlinear system. We show that iterating on the radiation energy density and the emission source is more robust. Since the Picard-Newton scheme may not converge for all initial conditions and time steps, pseudo-transient continuation (Ψtc) is introduced. The combined Ψtc-Picard-Newton scheme is analyzed. We derive conditions on the Ψtc parameter that guarantee physically meaningful iterates, e.g., positive energies. Successive Ψtc iterates are bounded and the radiation energy density and emission source tend to equilibrate. The scheme is incorporated into a multiply dimensioned, massively parallel, Eulerian, radiation-hydrodynamic computer program with automatic mesh refinement (AMR). Three examples are presented that exemplify the scheme's performance. (1) The Pomraning test problem that models radiation flow into cold matter. (2) A similar, but more realistic problem simulating the propagation of an ionization front into tenuous hydrogen gas with a Saha model for the equation-of-state. (3) A 2D axisymmetric (R,Z) simulation with real materials featuring jetting, radiatively driven, interacting shocks

  6. Globalization and the Brazilian balance accounts; Globalizacao e a balanca de pagamentos nuclear brasileira

    Urbina, Ligia M. Soto; Cabral, Arnoldo S. [Centro Tecnico Aeroespacial, Sao Jose dos Campos, SP (Brazil). Inst. Tecnologico de Aeronautica; Vieira, Wilson J. [Centro Tecnico Aeroespacial (CTA-IEAv), Sao Jose dos Campos, SP (Brazil). Inst. de Estudos Avancados

    1999-11-01

    The globalization of the world economy calls for a country specialization with new structures for the product sectors and an increase in the competitiveness in areas of specialization. This process requires the amplification of markets and the adoption of technological innovations which increase the volume of economic trade, but also change trade relations. This process is made possible because of price stabilization and the stability and transparency of the exchange rate policy of various countries. In this work it is shown the opportunity to place nuclear energy as one of the sectors in which Brazil may have competitive advantages and enhance its external balance accounts, by the competitive substitution of imports by producing internally goods and services which technology is known by Brazilian firms and because of the increase in exports. (author) 19 refs.

  7. Improved correlation of monthly mean daily and hourly diffuse radiation with the corresponding global radiation for Indian stations

    Garg, H.P.; Garg, S.N.

    1985-12-01

    Several existing correlations between radiation monthly mean ratios of global to extraterrestrial and diffuse to global were tried for four Indian stations and found inadequate. New correlations were established for these stations and it was shown that these correlations are highly climate dependent. Classical equation of Liu and Jordon was tried to find hourly diffuse and global radiation from daily sums of diffuse and global radiation respectively. It was suitably modified to suit the Indian data. Equations developed by Collares-Pereira and Rabl have shown excellent agreement with the observed values

  8. Radiative transfer model for estimation of global solar radiation; Modelo de transferencia radiativa para la estimacion de la radiacion solar global

    Pettazzi, A.; Sabon, C. S.; Souto, G. J. A.

    2004-07-01

    In this work, the efficiency of a radiative transfer model in estimating the annual solar global radiation has been evaluated, over different locations at Galicia, Spain, in clear sky periods. Due to its quantitative significance, special attention has been focused on the analysis of the influence of visibility over the global radiation. By comparison of both estimated and measured global solar radiation along year 2002, a typical annual visibility series was obtained over every location. These visibility values has been analysed in order to identify patterns and typical values, in order to be used to estimate the global solar radiation along a different year. Validation was done over the year 2003, obtaining an annual estimation less than 10 % different to the measured value. (Author)

  9. Energy and carbon balances in cheatgrass, an essay in autecology. [Shortwave radiation, radiowave radiation

    Hinds, W.T.

    1975-01-01

    An experiment to determine the fates of energy and carbon in cheatgrass (Bromus tectorum L.) was carried out on steep (40/sup 0/) north- and south-facing slopes on a small earth mound, using many small lysimeters to emulate swards of cheatgrass. Meteorological conditions and energy fluxes that were measured included air and soil temperatures, relative humidity, wind speed, incoming shortwave radiation, net all-wave radiation, heat flux to the soil, and evaporation and transpiration separately. The fate of photosynthetically fixed carbon during spring growth was determined by analysis of the plant tissues into mineral nutrients, crude protein, crude fat, crude fiber, and nitrogen-free extract (NFE) for roots, shoots, and seeds separately. (auth)

  10. Global source attribution of sulfate aerosol and its radiative forcing

    Yang, Y.; Wang, H.; Smith, S.; Easter, R. C.; Ma, P. L.; Qian, Y.; Li, C.; Yu, H.; Rasch, P. J.

    2017-12-01

    Sulfate is an important aerosol that poses health risks and influences climate. Due to long-range atmospheric transport, local sulfate pollution could result from intercontinental influences, making domestic efforts of improving air quality inefficient. Accurate understanding of source attribution of sulfate and its radiative forcing is important for both regional air quality improvement and global climate mitigation. In this study, for the first time, a sulfur source-tagging capability is implemented in the Community Atmosphere Model (CAM5) to quantify the global source-receptor relationships of sulfate and its direct and indirect radiative forcing (DRF and IRF). Near-surface sulfate concentrations are mostly contributed by local emissions in regions with high emissions, while over regions with relatively low SO2 emissions, the near-surface sulfate is primarily attributed to non-local sources from long-range transport. The export of SO2 and sulfate from Europe contributes 20% of sulfate concentrations over North Africa, Russia and Central Asia. Sources from the Middle East account for 20% of sulfate over North Africa, Southern Africa and Central Asia in winter and autumn, and 20% over South Asia in spring. East Asia accounts for about 50% of sulfate over Southeast Asia in winter and autumn, 15% over Russia in summer, and 10% over North America in spring. South Asia contributes to 25% of sulfate over Southeast Asia in spring. Lifetime of aerosols, together with regional export, is found to determine regional air quality. The simulated global total sulfate DRF is -0.42 W m-2, with 75% contributed by anthropogenic sulfate and 25% contributed by natural sulfate. In the Southern Hemisphere tropics, dimethyl sulfide (DMS) contributes the most to the total DRF. East Asia has the largest contribution of 20-30% over the Northern Hemisphere mid- and high-latitudes. A 20% perturbation of sulfate and its precursor emissions gives a sulfate IRF of -0.44 W m-2. DMS has the

  11. Seasonal changes in the radiation balance of subarctic forest and tundra

    Lafleur, P.M.; Renzetti, A.V.; Bello, R.

    1993-01-01

    This paper examines the seasonal behavior of the components of the radiation budget of subarctic tundra and open forest near Churchill, Manitoba. Data were collected between late February and August 1990. The presence of the winter snowpack is the most important factor which affects the difference in radiation balances of tundra and forest. Overall, net radiation was about four to five times larger over the forest when snow covered the ground. Albedo differences were primarily responsible for this difference in net radiation; however, somewhat smaller net longwave losses were experienced at the tundra site. The step decrease in albedo from winter to summer (i.e. snow-covered to snow-free conditions) was significant at both sites. The forest albedo decreased by about three-fold while the tundra experienced a seven-fold decrease. Net radiation at both sites increased in direct response to the albedo change. Transmissivity of the atmosphere near Churchill also appeared to change at about the same time as the loss of the snow cover and may be related to changing air masses which bring about the final snow melt

  12. Performance of Sayigh's universal formula in the estimation of global solar radiation in Ghana

    Oduro Afriyie, K.

    1995-10-01

    The performance of Sayigh's universal formula for the estimation of global solar radiation is tested against that of Angstrom-Black model for 13 stations in Ghana, using monthly mean daily global solar radiation averaged over the years 1957-1981. Sayigh's model is found not to perform as credibility as the Angstrom-Black model in the estimation of monthly global solar radiation in Ghana. Of the 156 values of monthly global solar radiation estimated by Sayigh's model, 123 (or 78.8%) had discrepancies of more than 10% with the measured values. The corresponding value for the Angstrom-Black model was 7 (or 4.5%). (author). 5 refs

  13. Radiation balance at the surface in the city of São Paulo, Brazil: diurnal and seasonal variations

    Ferreira, M.J.; Oliveira, de A.P.; Soares, J.; Codato, G.; Wilde Barbaro, E.; Escobedo, J.F.

    2012-01-01

    The main goal of this work is to describe the diurnal and seasonal variations of the radiation balance components at the surface in the city of São Paulo based on observations carried out during 2004. Monthly average hourly values indicate that the amplitudes of the diurnal cycles of net radiation

  14. Population-based mammography screening below age 50: Balancing radiation-induced vs prevented breast cancer deaths

    R. de Gelder (Rianne); G. Draisma (Gerrit); E.A.M. Heijnsdijk (Eveline); H.J. de Koning (Harry)

    2011-01-01

    textabstractIntroduction:Exposure to ionizing radiation at mammography screening may cause breast cancer. Because the radiation risk increases with lower exposure age, advancing the lower age limit may affect the balance between screening benefits and risks. The present study explores the

  15. A mathematical correlation between variations in solar radiation parameters. 2. Global radiation, air temperature and specific humidity

    Njau, E.C.

    1988-06-01

    We derive from first principles, an equation which expresses global radiation as a function of specific humidity and air temperature at screen height. The practical validity of this equation is tested by using humidity, air temperature and global radiation data from Tanzania. It is shown that global radiation values calculated on the basis of the derived equation agree with measured radiation values to within ± 8% as long as the prevalent (horizontal) winds are either calm or light. It is noted that the equation is equally valid at times of strong horizontal winds provided that the temperature and humidity measuring site is sufficiently shielded from the winds. This implies that meteorological stations that are (for some unavoidable reasons) unable to stock pyranometers can still procure reasonable estimates of local global radiation as long as they can, at least, stock the relatively cheaper barometers and wet- and dry-bulb psychrometers. (author). 12 refs, 1 fig., 4 tabs

  16. Influences of deforestation on radiation and heat balances in tropical peat swamp forest in Thailand

    Suzuki, S.; Ishida, T.; Nagano, T.; Matsukawa, S.

    1997-01-01

    The difference of radiation and heat balances between a natural peat swamp forest and a deforested secondary forest has been investigated in Narathiwat Province, Thailand. Micrometeorological measurements were conducted continuously on observation towers 38 m and 4 m in heights in the primary forest and the secondary forest respectively. Results show that the deforestation of peat swamp forest leads to an increase in the sensible heat flux in the secondary forest. The yearly average ratio of the sensible heat flux to the net radiation was 20.9% in the peat swamp forest, and 33.2% in the secondary forest from Aug. 1995 to Jul. 1996. A ratio more than 40% was observed only in the dry season in the secondary forest. The change in sensible heat flux seemed to be influenced by the change in ground water levels. (author)

  17. Fire-induced albedo change and surface radiative forcing in sub-Saharan Africa savanna ecosystems: Implications for the energy balance

    Dintwe, Kebonye; Okin, Gregory S.; Xue, Yongkang

    2017-06-01

    Surface albedo is a critical parameter that controls surface energy balance. In dryland ecosystems, fires play a significant role in decreasing surface albedo, resulting in positive radiative forcing. Here we investigate the long-term effect of fire on surface albedo. We devised a method to calculate short-, medium-, and long-term effect of fire-induced radiative forcing and their relative effects on energy balance. We used Moderate Resolution Imaging Spectroradiometer (MODIS) data in our analysis, covering different vegetation classes in sub-Saharan Africa (SSA). Our analysis indicated that mean short-term fire-induced albedo change in SSA was -0.022, -0.035, and -0.041 for savannas, shrubland, and grasslands, respectively. At regional scale, mean fire-induced albedo change in savannas was -0.018 and -0.024 for northern sub-Saharan of Africa and the southern hemisphere Africa, respectively. The short-term mean fire-induced radiative forcing in burned areas in sub-Saharan Africa (SSA) was 5.41 W m-2, which contributed continental and global radiative forcings of 0.25 and 0.058 W m-2, respectively. The impact of fire in surface albedo has long-lasting effects that varies with vegetation type. The long-term energetic effects of fire-induced albedo change and associated radiative forcing were, on average, more than 19 times greater across SSA than the short-term effects, suggesting that fires exerted far more radiative forcing than previously thought. Taking into account the actual duration of fire's effect on surface albedo, we conclude that the contribution of SSA fires, globally and throughout the year, is 0.12 W m-2. These findings provide crucial information on possible impact of fire on regional climate variability.

  18. GlobWat – a global water balance model to assess water use in irrigated agriculture (discussion paper)

    Hoogeveen, J.; Faures, J.M.; Peiser, L.; Burke, J.; Van de Giesen, N.C.

    2015-01-01

    GlobWat is a freely distributed, global soil water balance model that is used by FAO to assess water use in irrigated agriculture; the main factor behind scarcity of freshwater in an increasing number of regions. The model is based on spatially distributed high resolution datasets that are

  19. Regional Modeling of Dust Mass Balance and Radiative Forcing over East Asia using WRF-Chem

    Chen, Siyu; Zhao, Chun; Qian, Yun; Leung, Lai-Yung R.; Huang, J.; Huang, Zhongwei; Bi, Jianrong; Zhang, Wu; Shi, Jinsen; Yang, Lei; Li, Deshuai; Li, Jinxin

    2014-12-01

    The Weather Research and Forecasting model with Chemistry (WRF-Chem) is used to investigate the seasonal and annual variations of mineral dust over East Asia during 2007-2011, with a focus on the dust mass balance and radiative forcing. A variety of measurements from in-stu and satellite observations have been used to evaluate simulation results. Generally, WRF-Chem reproduces not only the column variability but also the vertical profile and size distribution of mineral dust over and near the dust source regions of East Asia. We investigate the dust lifecycle and the factors that control the seasonal and spatial variations of dust mass balance and radiative forcing over the seven sub-regions of East Asia, i.e. source regions, the Tibetan Plateau, Northern China, Southern China, the ocean outflow region, and Korea-Japan regions. Results show that, over the source regions, transport and dry deposition are the two dominant sinks. Transport contributes to ~30% of the dust sink over the source regions. Dust results in a surface cooling of up to -14 and -10 W m-2, atmospheric warming of up to 20 and 15 W m-2, and TOA cooling of -5 and -8 W m-2 over the two major dust source regions of East Asia, respectively. Over the Tibetan Plateau, transport is the dominant source with a peak in summer. Over identified outflow regions, maximum dust mass loading in spring is contributed by the transport. Dry and wet depositions are the comparably dominant sinks, but wet deposition is larger than dry deposition over the Korea-Japan region, particularly in spring (70% versus 30%). The WRF-Chem simulations can generally capture the measured features of dust aerosols and its radaitve properties and dust mass balance over East Asia, which provides confidence for use in further investigation of dust impact on climate over East Asia.

  20. Towards a sustainable global energy supply infrastructure: Net energy balance and density considerations

    Kessides, Ioannis N.; Wade, David C.

    2011-01-01

    This paper employs a framework of dynamic energy analysis to model the growth potential of alternative electricity supply infrastructures as constrained by innate physical energy balance and dynamic response limits. Coal-fired generation meets the criteria of longevity (abundance of energy source) and scalability (ability to expand to the multi-terawatt level) which are critical for a sustainable energy supply chain, but carries a very heavy carbon footprint. Renewables and nuclear power, on the other hand, meet both the longevity and environmental friendliness criteria. However, due to their substantially different energy densities and load factors, they vary in terms of their ability to deliver net excess energy and attain the scale needed for meeting the huge global energy demand. The low power density of renewable energy extraction and the intermittency of renewable flows limit their ability to achieve high rates of indigenous infrastructure growth. A significant global nuclear power deployment, on the other hand, could engender serious risks related to proliferation, safety, and waste disposal. Unlike renewable sources of energy, nuclear power is an unforgiving technology because human lapses and errors can have ecological and social impacts that are catastrophic and irreversible. Thus, the transition to a low carbon economy is likely to prove much more challenging than early optimists have claimed. - Highlights: → We model the growth potential of alternative electricity supply infrastructures. → Coal is scalable and abundant but carries a heavy carbon footprint. → Renewables and nuclear meet the longevity and environmental friendliness criteria. → The low power density and intermittency of renewables limit their growth potential. → Nuclear power continues to raise concerns about proliferation, safety, and waste.

  1. Aedes aegypti Global Suitability Maps Using a Water Container Energy Balance Model for Dengue Risk Applications

    Steinhoff, D.

    2015-12-01

    Dengue infections are estimated to total nearly 400 million per year worldwide, with both the geographic range and the magnitude of infections having increased in the past 50 years. The primary dengue vector mosquito Aedes aegypti is closely associated with humans. It lives exclusively in urban and semi-urban areas, preferentially bites humans, and spends its developmental stages in artificial water containers. Climate regulates the development of Ae. aegypti immature mosquitoes in artificial containers. Potential containers for Ae. aegypti immature development include, but are not limited to, small sundry items (e.g., bottles, cans, plastic containers), buckets, tires, barrels, tanks, and cisterns. Successful development of immature mosquitoes from eggs to larvae, pupae, and eventually adults is largely dependent on the availability of water and the thermal properties of the water in the containers. Recent work has shown that physics-based approaches toward modeling container water properties are promising for resolving the complexities of container water dynamics and the effects on immature mosquito development. An energy balance container model developed by the author, termed the Water Height And Temperature in Container Habitats Energy Model (WHATCH'EM), solves for water temperature and height for user-specified containers with readily available weather data. Here we use WHATCH'EM with NASA Earth Science products used as input to construct global suitability maps based on established water temperature ranges for immature Ae. aegypti mosquitoes. A proxy for dengue risk is provided from habitat suitability, but also population estimates, as Ae. aegypti is closely associated with human activity. NASA gridded Global Population of the World data is used to mask out rural areas with low dengue risk. Suitability maps are illustrated for a variety of containers (size, material, color) and shading scenarios.

  2. Downscaling of the global climate model data for the mass balance calculation of mountain glaciers

    P. A. Morozova

    2017-01-01

    Full Text Available In this paper, we consider a hybrid method of downscaling of the GCM‑generated meteorological fields to the characteristic spatial resolution which is usually used for modeling of a single mountain glacier mass balance. The main purpose of the study is to develop a reliable forecasting method to evaluate future state of moun‑ tain glaciation under changing climatic conditions. The method consists of two stages. In the first or dynamical stage, we use results of calculations of the regional numerical model HadRM3P for the Black Sea‑Caspian region with a spatial resolution of 25 km [22]. Initial conditions for the HadRM3P were provided by the GCM devel‑ oped in the Institute of Numerical Mathematics of RAS (INMCM4 [18]. Calculations were carried out for two time periods: the present climate (1971–2000 and climate in the late 21st century (2071–2100 according to the scenario of greenhouse gas emissions RCP 8.5. On the second stage of downscaling, further regionalization is achieved by projecting of RCM‑generated data to the high‑resolution (25 m digital altitude model in a domain enclosing a target glacier. Altitude gradients of the surface air temperature and precipitation were derived from the model data. Further on, both were corrected using data of observations. Incoming shortwave radiation was calculated in the mass balance model separately, taking into account characteristics of the slope, i.e. exposition and shading of each cell. Then, the method was tested for glaciers Marukh (Western Caucasus and Jankuat (Central Caucasus, both for the present‑day and for future climates. At the end of the 21st century, the air tem‑ perature rise predicted for the summer months was calculated to be about 5–6 °C, and the result for the winter to be minus 2–3 °C. Change in annual precipitation is not significant, less than 10%. Increase in the total short‑ wave radiation will be about 5%. These changes will result in the fact that

  3. Global Classical Solutions for Partially Dissipative Hyperbolic System of Balance Laws

    Xu, Jiang; Kawashima, Shuichi

    2014-02-01

    The basic existence theory of Kato and Majda enables us to obtain local-in-time classical solutions to generally quasilinear hyperbolic systems in the framework of Sobolev spaces (in x) with higher regularity. However, it remains a challenging open problem whether classical solutions still preserve well-posedness in the case of critical regularity. This paper is concerned with partially dissipative hyperbolic system of balance laws. Under the entropy dissipative assumption, we establish the local well-posedness and blow-up criterion of classical solutions in the framework of Besov spaces with critical regularity with the aid of the standard iteration argument and Friedrichs' regularization method. Then we explore the theory of function spaces and develop an elementary fact that indicates the relation between homogeneous and inhomogeneous Chemin-Lerner spaces (mixed space-time Besov spaces). This fact allows us to capture the dissipation rates generated from the partial dissipative source term and further obtain the global well-posedness and stability by assuming at all times the Shizuta-Kawashima algebraic condition. As a direct application, the corresponding well-posedness and stability of classical solutions to the compressible Euler equations with damping are also obtained.

  4. O Brasil na iniciativa BRIC: soft balancing numa ordem global em mudança? Brazil in the BRIC initiative: soft balancing in the shifting world order?

    Daniel Flemes

    2010-07-01

    Full Text Available As opções de política externa do Brasil são limitadas, tendo em conta os recursos materiais superiores das grandes potências establecidas. Soft balancing envolve estratégias institucionais, tais como a formação de coalizões ou ententes diplomáticas limitadas, como BRIC, para restringir o poder das grandes potências estabelecidas. Os países BRIC tinham constado dentre os precursores mais fortes de mudança da diplomacia mundial e por sua vez se beneficiam mais destas mudanças de poder global. Dentro da ordem global modelada pelas grandes potências por meio de instituições internacionais, aqueles jogadores que operam efetivamente dentro destas como inovadores, formadores de alianças e porta-vozes, e que ao mesmo tempo conservam soberania e independência têm o potencial de influir sustancialmente os resultados de políticas futuras.The foreign policy options of Brazil are limited in view of the superior hard power of the established great powers. Brazil's soft balancing strategy involves institutional strategies such as the formation of limited diplomatic coalitions or ententes, such as BRIC, to constrain the power of the established great powers. The BRIC states have been amongst the most powerful drivers of incremental change in world diplomacy and they benefit most from the connected global power shifts. In a global order shaped by great powers through international institutions, those players who effectively operate within them as innovators, coalition builders and spokesmen while preserving great amounts of sovereignty and independence have the potential to substantially influence the outcomes of future global politics.

  5. An Assessment of the Current US Radiation Oncology Workforce: Methodology and Global Results of the American Society for Radiation Oncology 2012 Workforce Study

    Vichare, Anushree; Washington, Raynard; Patton, Caroline; Arnone, Anna [ASTRO, Fairfax, Virginia (United States); Olsen, Christine [Massachusetts General Hospital, Boston, Massachusetts, (United States); Fung, Claire Y. [Commonwealth Newburyport Cancer Center, Newburyport, Massachusetts (United States); Hopkins, Shane [William R. Bliss Cancer Center, Ames, Iowa (United States); Pohar, Surjeet, E-mail: spohar@netzero.net [Indiana University Health Cancer Center East, Indiana University, Indianapolis, Indiana (United States)

    2013-12-01

    Purpose: To determine the characteristics, needs, and concerns of the current radiation oncology workforce, evaluate best practices and opportunities for improving quality and safety, and assess what we can predict about the future workforce. Methods and Materials: An online survey was distributed to 35,204 respondents from all segments of the radiation oncology workforce, including radiation oncologists, residents, medical dosimetrists, radiation therapists, medical physicists, nurse practitioners, nurses, physician assistants, and practice managers/administrators. The survey was disseminated by the American Society for Radiation Oncology (ASTRO) together with specialty societies representing other workforce segments. An overview of the methods and global results is presented in this paper. Results: A total of 6765 completed surveys were received, a response rate of 19%, and the final analysis included 5257 respondents. Three-quarters of the radiation oncologists, residents, and physicists who responded were male, in contrast to the other segments in which two-thirds or more were female. The majority of respondents (58%) indicated they were hospital-based, whereas 40% practiced in a free-standing/satellite clinic and 2% in another setting. Among the practices represented in the survey, 21.5% were academic, 25.2% were hospital, and 53.3% were private. A perceived oversupply of professionals relative to demand was reported by the physicist, dosimetrist, and radiation therapist segments. An undersupply was perceived by physician's assistants, nurse practitioners, and nurses. The supply of radiation oncologists and residents was considered balanced. Conclusions: This survey was unique as it attempted to comprehensively assess the radiation oncology workforce by directly surveying each segment. The results suggest there is potential to improve the diversity of the workforce and optimize the supply of the workforce segments. The survey also provides a benchmark for

  6. An Assessment of the Current US Radiation Oncology Workforce: Methodology and Global Results of the American Society for Radiation Oncology 2012 Workforce Study

    Vichare, Anushree; Washington, Raynard; Patton, Caroline; Arnone, Anna; Olsen, Christine; Fung, Claire Y.; Hopkins, Shane; Pohar, Surjeet

    2013-01-01

    Purpose: To determine the characteristics, needs, and concerns of the current radiation oncology workforce, evaluate best practices and opportunities for improving quality and safety, and assess what we can predict about the future workforce. Methods and Materials: An online survey was distributed to 35,204 respondents from all segments of the radiation oncology workforce, including radiation oncologists, residents, medical dosimetrists, radiation therapists, medical physicists, nurse practitioners, nurses, physician assistants, and practice managers/administrators. The survey was disseminated by the American Society for Radiation Oncology (ASTRO) together with specialty societies representing other workforce segments. An overview of the methods and global results is presented in this paper. Results: A total of 6765 completed surveys were received, a response rate of 19%, and the final analysis included 5257 respondents. Three-quarters of the radiation oncologists, residents, and physicists who responded were male, in contrast to the other segments in which two-thirds or more were female. The majority of respondents (58%) indicated they were hospital-based, whereas 40% practiced in a free-standing/satellite clinic and 2% in another setting. Among the practices represented in the survey, 21.5% were academic, 25.2% were hospital, and 53.3% were private. A perceived oversupply of professionals relative to demand was reported by the physicist, dosimetrist, and radiation therapist segments. An undersupply was perceived by physician's assistants, nurse practitioners, and nurses. The supply of radiation oncologists and residents was considered balanced. Conclusions: This survey was unique as it attempted to comprehensively assess the radiation oncology workforce by directly surveying each segment. The results suggest there is potential to improve the diversity of the workforce and optimize the supply of the workforce segments. The survey also provides a benchmark for

  7. TOA Radiation Balance Study through Reprocessed ERBS WFOV Nonscanner data from 1985 to 1998

    Shrestha, A. K.; Kato, S.; Wong, T.; Stackhouse, P. W., Jr.; Doelling, D. R.; Loughman, R. P.

    2017-12-01

    Wide-field-of-view (WFOV) nonscanner instrument onboard Earth Radiation Budget Satellite (ERBS) provided broadband irradiances at the top-of-atmosphere (TOA) from 1985 to 1999. However, earlier studies show that the uncertainty in this TOA radiation dataset is significantly higher during the period after the Mt. Pinatubo eruption and battery issue in 1991. In addition, the difference between daytime and nighttime longwave irradiance drifts with time throughout the lifetime of the instrument. We re-processed ERBS WFOV data using the algorithm similar to the one used in the CERES project and calibrated it with CERES-derived irradiances. In addition, the spatial coverage of ERBS irradiances is extended to global from near-global (60°N to 60°S latitudes) using CERES climatological ratio of the near-global to global mean irradiances. The near-global standard deviation of deseasonalized shortwave anomalies computed with Ed4 decreases to 3.2 Wm-2 from 8.0 Wm-2, computed with previous version. In addition, the drift of day-minus-night longwave irradiance is reduced by one third. Similar to the previous version, however, the Ed4 global shortwave irradiance averaged over the 1994 to 1997 period (second period) is smaller by 2.2 Wm-2 compared to that averaged over the 1985 to 1989 period (first period). In addition, the global longwave irradiance in the second period is larger by 0.7 Wm-2 compared to that averaged over the first period. When the difference of two periods is computed (second period minus first period) with the DEEP-C data product (Allan et al. 2014), the difference is 0.5 (-0.3) Wm-2 for shortwave (longwave). The global net imbalance at the TOA computed with ERBS and DEEP-C data sets are, respectively, 0.45 (1.89) Wm-2 and 0.17 (0.96) Wm-2 for the first (second) period. The net imbalance for the CERES period in the 2000s is 0.65 Wm-2. In this presentation, we will further compare Ed4 ERBS-derived TOA net imbalance with ocean heating rates. Re-processed ERBS

  8. Response of normal stem cells to ionizing radiation: A balance between homeostasis and genomic stability

    Harfouche, G.; Martin, M.T.

    2010-01-01

    Stem cells have been described in most adult tissues, where they play a key role in maintaining tissue homeostasis. As they self-renew throughout life, accumulating genetic anomalies can compromise their genomic integrity and potentially give rise to cancer. Stem cells (SCs) may thus be a major target of radiation carcinogenesis. In addition, unrepaired genotoxic damage may cause cell death and stem cell pool depletion, impairing lineage functionality and accelerating aging. Developments in SC biology enabled the characterization of the responses of stem cells to genotoxic stress and their role in tissue damage. We here examine how these cells react to ionizing radiation (IR), and more specifically their radiosensitivity, stress signaling and DNA repair. We first review embryonic SCs, as a paradigm of primitive pluri-potent cells, then three adult tissues, bone marrow, skin and intestine, capable of long-term regeneration and at high risk for acute radiation syndromes and long-term carcinogenesis. We discuss IR disruption of the fine balance between maintenance of tissue homeostasis and genomic stability. We show that stem cell radiosensitivity does not follow a unique model, but differs notably according to the turnover rates of the tissues. (authors)

  9. Estimation of global solar radiation by means of sunshine duration

    Luis, Mazorra Aguiar; Felipe, Diaz Reyes [Electrical Engineering Dept., Las Palmas de Gran Canaria Univ. (U.L.P.G.C.), Campus Univ. Tafira (Spain); Pilar, Navarro Rivero [Canary Islands Technological Inst. (I.T.C.), Gran Canaria (Spain)

    2008-07-01

    This paper analyses the relationship between global solar irradiation and sunshine duration with different estimation models for the island of Gran Canaria (Spain). These parameters were taken from six measurement stations around the Island, and selected for their reliability and the long period of time they covered. All data used in this paper were handed over by the Canary Islands Technological Institute (I.T.C.). As a first approach, it was decided to study the Angstrom lineal model. In order to improve the knowledge on solar resources, a Typical Meteorological Year (TMY) was created from all daily data. TMY shows differences between southern and northern locations, where Trade Winds generate clouds during the summer months. TMY resumes a data bank much longer than a year in duration, generating the characteristics for a year series of each location, for both irradiation and sunshine duration. To create the TMY, weighted means have been used to smooth high or low values. At first, Angstrom lineal model has been used to estimate solar global irradiation from sunshine duration values, using TMY. But the lineal model didn't reproduce satisfactory results when used to obtain global solar radiation from all daily sunshine duration data. For this reason, different models based in both parameters were used. The parameters estimation of this model was achieved both from TMY daily and monthly series and from all daily data for every location. Because of the weather stability all over the year in the Island, most of the daily data are concentrated in a close range, occasioning a deviation in the lineal equations. To avoid this deviation it was proposed to consider a limit condition data, taking into account values out of the main cloud of data. Additionally, different models were proposed (quadratic, cubic, logarithmic and exponential) to make a regression from all daily data. The best results were obtained with the exponential model proposed in this paper. The

  10. Participation of the radiation hygiene laboratories to the WHO/UNEP global environmental radiation network

    Milu, C.; Gheorghe, R.

    2003-01-01

    In December 1987, a WHO-UNEP meeting held at SCPRI (Service Central de protection canter Les Rayonnements Ionisantes - Le Vesinet, France) set up the basis of the international network GERMON (Global Environmental Radiation Monitoring Network) as an extension of existing network 'Global Environment Monitoring Systems' (GEMS). The accident from Chernobyl certainly was the important nuclear event influencing this decision. The aim of the GERMON network is to initiate programmes for the routine monitoring of the environmental radioactivity and to ensure a quick interchange of credible data in case of major accidental radioactive releases, as well as the development of intervention devices in the member states running such programmes. The responsibility of the Co-ordinating Collaborating Centre (CCC) has been given to the French Service Central de Protection Centre les Rayonnements Ionisants (SCPRI). In 1994, this Service became the Office de Protection Centre les Rayonnements Ionisants (OPRI). The Ministry of Health has a national network consisting of 23 radiation hygiene laboratories; 19 of these are included in the framework of county divisions of public health , and the other 4 are compartments of the regional institutes of public health. WHO designated the Institute of Public Health from Bucharest as National Contact Centre, in charge with communicating the results obtained by the national laboratories on the indicators of environmental radioactivity, according to the established methodologies. The main indicators considered are: ambient gamma dose, radioactivity of the air, of the precipitation, and of the milk. Following the measurement and transmission protocols of the CCC, the Radiation Hygiene Laboratory from the Institute of Public Health has established a methodology to be followed by the laboratories of the national network. (authors)

  11. Measurements of integrated direct, diffuse and global ultraviolet-B radiation

    Utrillas, M.P.; Pedrós, R.; Gandía, S.; Gómez-Amo, J.L.; Estellés, V.; Martínez-Lozano, J.A.

    2015-01-01

    We present the first multiyear set of simultaneous measurements of the global ultraviolet-B radiation and its two components: direct and diffuse. The measurements have been taken with four YES-UVB-1 radiometers: two radiometers to measure the diffuse radiation, one provided with a shadow band and the other with a shadow disk on a Sun tracker; a radiometer to measure the global horizontal radiation; and a Sun-tracking radiometer to measure the direct radiation with an especially designed radiance collimator. The diffuse minute-values measured with both instruments agree within a coefficient correlation of 1.00. The diffuse component represents at least 50% of the global UVB (ultraviolet-B) radiation. The minute values of global UVB irradiance obtained by adding the direct and diffuse components concur with the measured global irradiance. Therefore, the measurement of the direct irradiance enables the estimation of the diffuse component, and gives an insight into the factors that affect its value, especially aerosols. - Highlights: • Simultaneous measurements of global, direct and diffuse UVB (ultraviolet-B) radiation. • The diffuse minute-values are at least 50% of the global ones. • The diffuse measurements are highly correlated to the aerosol load. • The sum of direct + diffuse radiation concur with the measured global.

  12. Troughs in Ice Sheets and Other Icy Deposits on Mars: Analysis of Their Radiative Balance

    Fountain, A.; Kargel, J.; Lewis, K.; MacAyeal, D.; Pfeffer, T.; Zwally, H. J.

    2000-01-01

    It has long been known that groove-like structures in glaciers and ice sheets can trap more incoming solar radiation than is the case for a 'normal' flat, smooth surface. In this presentation, we shall describe the radiative regimes of typical scarps and troughs on icy surfaces of Mars, and suggest how these features originate and evolve through time. The basis of our analysis is the radiation balance model presented by Pfeffer and Bretherton. Their model considers the visible band radiation regime of a V-shaped groove on a terrestrial ice surface, and shows that absorbed energy can be enhanced by up to 50 percent for grooves with small opening angles and with typical polar values of the solar zenith angle. Our work extends this model by considering: (a) departures from V-shaped geometry, (b) both englacial and surficial dust and debris, and (c) the infrared spectrum. We apply the extended model to various features on the Martian surface, including the spiral-like scarps on the Northern and Southern ice sheets, the large-scale chasms (e.g., Chasm Borealis), and groove-like lineations on valley floors thought to be filled with mixtures of dust and icy substances. In conjunction with study of valley-closure experiments, we suggest that spiral-like scarps and chasms are stable features of the Martian climate regime. We also suggest that further study of scarps and chasms may shed light on the composition (i.e., relative proportions of water ice, carbon-dioxide ice and dust) of the Martian ice sheets and valley fills.

  13. Prediction of monthly average global solar radiation based on statistical distribution of clearness index

    Ayodele, T.R.; Ogunjuyigbe, A.S.O.

    2015-01-01

    In this paper, probability distribution of clearness index is proposed for the prediction of global solar radiation. First, the clearness index is obtained from the past data of global solar radiation, then, the parameters of the appropriate distribution that best fit the clearness index are determined. The global solar radiation is thereafter predicted from the clearness index using inverse transformation of the cumulative distribution function. To validate the proposed method, eight years global solar radiation data (2000–2007) of Ibadan, Nigeria are used to determine the parameters of appropriate probability distribution for clearness index. The calculated parameters are then used to predict the future monthly average global solar radiation for the following year (2008). The predicted values are compared with the measured values using four statistical tests: the Root Mean Square Error (RMSE), MAE (Mean Absolute Error), MAPE (Mean Absolute Percentage Error) and the coefficient of determination (R"2). The proposed method is also compared to the existing regression models. The results show that logistic distribution provides the best fit for clearness index of Ibadan and the proposed method is effective in predicting the monthly average global solar radiation with overall RMSE of 0.383 MJ/m"2/day, MAE of 0.295 MJ/m"2/day, MAPE of 2% and R"2 of 0.967. - Highlights: • Distribution of clearnes index is proposed for prediction of global solar radiation. • The clearness index is obtained from the past data of global solar radiation. • The parameters of distribution that best fit the clearness index are determined. • Solar radiation is predicted from the clearness index using inverse transformation. • The method is effective in predicting the monthly average global solar radiation.

  14. Request for Funding for the 2016 Air & Waste Management Association Visibility Conference on Atmospheric Optics:Aerosols, Visibility, and the Radiative Balance

    Eatough, Delbert

    2016-01-01

    This international conference will provide a technical forum on advances in the scientific understanding of the effects of aerosols on urban, regional, continental, and global-scale haze and the radiative balance. The conference will take a multipronged approach and address scientific topics (e.g., related to measurements, modeling, etc.) as well as regulatory and policy issues. There will be sessions on black and brown carbon, as recent research has shown the importance of these particles for radiative forcing. In addition, there will be sessions related to the synergistic and increasing concerns of the effects of atmospheric nitrogen and carbonaceous material on haze, climate change, and nitrogen deposition on ecosystems. Conference learning will be enhanced with a half day excursion and hikes in Grand Teton National Park and a Night Sky Program.

  15. Request for Funding for the 2016 Air & Waste Management Association Visibility Conference on Atmospheric Optics:Aerosols, Visibility, and the Radiative Balance

    Eatough, Delbert [Brigham Young Univ., Provo, UT (United States)

    2016-06-01

    This international conference will provide a technical forum on advances in the scientific understanding of the effects of aerosols on urban, regional, continental, and global-scale haze and the radiative balance. The conference will take a multipronged approach and address scientific topics (e.g., related to measurements, modeling, etc.) as well as regulatory and policy issues. There will be sessions on black and brown carbon, as recent research has shown the importance of these particles for radiative forcing. In addition, there will be sessions related to the synergistic and increasing concerns of the effects of atmospheric nitrogen and carbonaceous material on haze, climate change, and nitrogen deposition on ecosystems. Conference learning will be enhanced with a half day excursion and hikes in Grand Teton National Park and a Night Sky Program.

  16. Test models for estimating radiation balance in different scales for Jaboticabal, SP

    Valquíria de Alencar Beserra

    2012-12-01

    Full Text Available The net radiation (Rn in agroecosystems is the amount of energy that is available in the environment to heating processes of living organisms, air and soil; perspiration of animals and plants; photosynthesis and water evaporation. The Rn defines the type of climate and weather conditions prevailing in a region affecting the availability and thermal water, the fundamental understanding of genotype-environment, which ultimately determine the productivity of the agricultural system. Rn usually is used in models of weather and climate studies. The sustainability and economic viability of zootechnical activity is dependent on the positive interaction between animal and environment. Environmental factors such as water, shading, thermal exchanges sensible heat (conduction, convection and radiation skin and latent heat losses (evaporation and transpiration, conditioned by Rn, must be managed to provide the best results. The present study was conducted to develop and test models for accurate and precise radiation balance on the scales daily, monthly and seasonal ten-day for Jaboticabal - SP, due to the importance of estimates of net radiation for agricultural activities. We used daily meteorological data from weather station located in Jaboticabal, SP (coordinates: 21 ° 14'05 "South, 48 ° 17'09" West, 615m altitude at Universidade Estadual Paulista "Júlio Mesquita Filho" - FCAV/UNESP in a situation of default grass "Bahiagrass" during the period 20/08/2005 to 20/01/2012. The data used were the maximum temperature (Tmax, minimum (Tmin and mean (TMED; maximum relative humidity (URMáx, minimum (URMín and average (URMéd precipitation (mm, average velocity (m/s, Qo, solar radiation (MJ m-2, sunshine (hour meter (MJ m², soil temperature at two depths (Tsoil2CM, Tsoil5CM and class A pan evaporation (TCA (mm. The measures taken by the balance radiometer were taken as a reference to test other models. The models tested were those reported by NORMAN et al

  17. 21st century changes in the surface mass balance of the Greenland ice sheet simulated with the global model CESM

    Vizcaíno, M.; Lipscomb, W. H.; Van den Broeke, M.

    2012-04-01

    We present here the first projections of 21st century surface mass balance change of the Greenland ice sheet simulated with the Community Earth System Model (CESM). CESM is a fully-coupled, global climate model developed at many research centers and universities, primarily in the U.S. The model calculates the surface mass balance in the land component (the Community Land Model, CLM), at the same resolution as the atmosphere (1 degree), with an energy-balance scheme. The snow physics included in CLM for non-glaciated surfaces (SNiCAR model, Flanner and Zender, 2005) are used over the ice sheet. The surface mass balance is calculated for 10 elevation classes, and then downscaled to the grid of the ice sheet model (5 km in this case) via vertical linear interpolation between elevation classes combined with horizontal bilinear interpolation. The ice sheet topography is fixed at present-day values for the simulations presented here. The use of elevation classes reduces computational costs while giving results that reproduce well the mass balance gradients at the steep margins of the ice sheet. The simulated present-day surface mass balance agrees well with results from regional models. We focus on the regional model RACMO (Ettema et al. 2009) to compare the results on 20th-century surface mass balance evolution and two-dimensional patterns. The surface mass balance of the ice sheet under RCP8.5. forcing becomes negative in the last decades of the 21st century. The equilibrium line becomes ~500 m higher on average. Accumulation changes are positive in the accumulation zone. We examine changes in refreezing, accumulation, albedo, surface fluxes, and the timing of the melt season.

  18. Experimental study of the ultraviolet global radiation in San Jose, Costa Rica

    Wright, J.

    1996-01-01

    The ultraviolet global radiation and the global solar radiation at San Jose, Costa Rica (latitude: 9 0 56', longitude: 84 0 54', altitude: 1.172 m.) during the period October 1993 to January 1995 were analyzed with respect to their seasonal variations and their independence. The dependence between the ultraviolet radiation and the clearness index of the skies was also investigated. A poor correlation was found between the quotient of the ultraviolet radiation (Hv/Hg) and between the global solar radiation and the extraterrestrial solar radiation (Hg/Ho). The correlation coefficient found between Hv/Hg and Hg/Ho was not greater than 0.25 for four categories of clearness index, i.e., covered skies, clear skies, and two intermediate conditions. This demonstrates that the ultraviolet radiation is not only associated with other atmospheric transmission conditions. A regression analysis between the hourly values of the ultraviolet and global radiation yielded a linear relationship with a determination coefficient greater than 98%. Thus a simple linear regression is reliable for the estimation of the ultraviolet in San Jose from global solar radiation data. (author) [es

  19. Determination of atmospheric parameters to estimate global radiation in areas of complex topography: Generation of global irradiation map

    Batlles, F.J.; Bosch, J.L. [Dpto. Fisica Aplicada, Universidad de Almeria, 04120 Almeria (Spain); Tovar-Pescador, J. [Dpto. Fisica, Universidad de Jaen, 23071 Jaen (Spain); Martinez-Durban, M. [Dpto. Ingenieria Lenguajes y Computacion, Universidad de Almeria, 04120 Almeria (Spain); Ortega, R. [Dpto. Edafologia y Quimica Agricola, Universidad de Almeria, 04120 Almeria (Spain); Miralles, I. [Dpto. Edafologia y Quimica Agricola, Universidad de Granada, 28071 Granada (Spain)

    2008-02-15

    Incoming shortwave solar radiation is an important parameter in environmental applications. A detailed spatial and temporal analysis of global solar radiation on the earth surface is needed in many applications, ranging from solar energy uses to the study of agricultural, forest and biological processes. At local scales, the topography is the most important factor in the distribution of solar radiation on the surface. The variability of the elevation, the surface orientation and the obstructions due to elevations are a source of great local differences in insolation and, consequently, in other variables as ground temperature. For this reason, several models based on GIS techniques have been recently developed, integrating topography to obtain the solar radiation on the surface. In this work, global radiation is analyzed with the Solar Analyst, a model implemented on ArcView, that computes the topographic parameters: altitude, latitude, slope and orientation (azimuth) and shadow effects. Solar Analyst uses as input parameters the diffuse fraction and the transmittance. These parameters are not usually available in radiometric networks in mountainous areas. In this work, a method to obtain both parameters from global radiation is proposed. Global radiation data obtained in two networks of radiometric stations is used: one located in Sierra Magina Natural Park (Spain) with 11 stations and another one located on the surroundings of Sierra Nevada Natural Park (Spain) with 14 stations. Daily solar irradiation is calculated from a digital terrain model (DTM), the daily diffuse fraction, K, and daily atmospheric transmittivity, {tau}. Results provided by the model have been compared with measured values. An overestimation for high elevations is observed, whereas low altitudes present underestimation. The best performance was also reported during summer months, and the worst results were obtained during winter. Finally, a yearly global solar irradiation map has been

  20. Global energy balance 2009 - USIMINAS - Jose Bonifacio de Andrade e Silva plant - Cubatao, SP, Brazil; Balanco energetico global 2009 - USIMINAS - Usina Jose Bonifacio de Andrade e Silva - Cubatao, SP

    Frias, Andre Luiz Pereira; Silva, Uilian Rodrigues da [Usinas Siderurgicas de Minas Gerais S/A (USIMINAS), Ipatinga, MG (Brazil)

    2010-07-01

    The global energetic balance of the USIMINAS - Cubatao Plant - in the year 2009 is presented containing the main indicators of energy consumption of the production areas. Besides the global energetic indicators, the balance presents the specific physical consumption at the different areas, allowing the analysis of each sector of the plant.

  1. TerraClimate, a high-resolution global dataset of monthly climate and climatic water balance from 1958–2015

    Abatzoglou, John T.; Dobrowski, Solomon Z.; Parks, Sean A.; Hegewisch, Katherine C.

    2018-01-01

    We present TerraClimate, a dataset of high-spatial resolution (1/24°, ~4-km) monthly climate and climatic water balance for global terrestrial surfaces from 1958–2015. TerraClimate uses climatically aided interpolation, combining high-spatial resolution climatological normals from the WorldClim dataset, with coarser resolution time varying (i.e., monthly) data from other sources to produce a monthly dataset of precipitation, maximum and minimum temperature, wind speed, vapor pressure, and sol...

  2. Reductions in soil surface albedo as a function of biochar application rate: implications for global radiative forcing

    Verheijen, Frank G A; Bastos, Ana Catarina; Keizer, Jan Jacob; Jeffery, Simon; Van der Velde, Marijn; Penížek, Vít; Beland, Martin

    2013-01-01

    Biochar can be defined as pyrolysed (charred) biomass produced for application to soils with the aim of mitigating global climate change while improving soil functions. Sustainable biochar application to soils has been estimated to reduce global greenhouse gas emissions by 71–130 Pg CO 2 -C e over 100 years, indicating an important potential to mitigate climate change. However, these estimates ignored changes in soil surface reflection by the application of dark-coloured biochar. Through a laboratory experiment we show a strong tendency for soil surface albedo to decrease as a power decay function with increasing biochar application rate, depending on soil moisture content, biochar application method and land use. Surface application of biochar resulted in strong reductions in soil surface albedo even at relatively low application rates. As a first assessment of the implications for climate change mitigation of these biochar–albedo relationships, we applied a first order global energy balance model to compare negative radiative forcings (from avoided CO 2 emissions) with positive radiative forcings (from reduced soil surface albedos). For a global-scale biochar application equivalent to 120 t ha −1 , we obtained reductions in negative radiative forcings of 5 and 11% for croplands and 11 and 23% for grasslands, when incorporating biochar into the topsoil or applying it to the soil surface, respectively. For a lower global biochar application rate (equivalent to 10 t ha −1 ), these reductions amounted to 13 and 44% for croplands and 28 and 94% for grasslands. Thus, our findings revealed the importance of including changes in soil surface albedo in studies assessing the net climate change mitigation potential of biochar, and we discuss the urgent need for field studies and more detailed spatiotemporal modelling. (letter)

  3. A study of the radiative forcing and global warming potentials of hydrofluorocarbons

    Zhang Hua; Wu Jinxiu; Lu Peng

    2011-01-01

    We developed a new radiation parameterization of hydrofluorocarbons (HFCs), using the correlated k-distribution method and the high-resolution transmission molecular absorption (HITRAN) 2004 database. We examined the instantaneous and stratospheric adjusted radiative efficiencies of HFCs for clear-sky and all-sky conditions. We also calculated the radiative forcing of HFCs from preindustrial times to the present and for future scenarios given by the Intergovernmental Panel on Climate Change Special Report on Emission Scenarios (SRES, in short). Global warming potential and global temperature potential were then examined and compared on the basis of the calculated radiative efficiencies. Finally, we discuss surface temperature changes due to various HFC emissions.

  4. Environmental radiation monitoring system with GPS (global positioning system)

    Komoto, Itsuro

    2000-01-01

    This system combines a radiation monitoring car with GPS and a data processor (personal computer). It distributes the position information acquired through GPS to the data such as measured environmental radiation dose rate and energy spectrum. It also displays and edits the data for each measuring position on a map. Transmitting the data to the power station through mobile phone enables plan managers to easily monitor the environmental radiation dose rate nearby and proper emergency monitoring. (author)

  5. The potential of global solar radiation in the Silesia region as a renewable source of energy

    Waniek Katarzyna

    2016-12-01

    Full Text Available Historically, Silesia has been at the centre of the Polish coal industry for many years and thus has experienced poorer air quality compared to other voivodeships. However, in recent years strong economic transformation in the area has led to a considerable reduction in coal production. This study aimed to assess the variability of global solar radiation at selected stations within the Silesian voivodeship, in order to re-evaluate the resources of renewable solar energy during the period 1994–2013. The theoretical potential of solar radiation was calculated based on a three-dimensional terrain model. The data on global solar radiation from 13 stations within the Silesia region, covering the period 1994–2013, were obtained from the Regional Inspectorate of Environmental Protection in Katowice. The most favourable conditions for the use of solar energy were found at the cities Sosnowiec and Cieszyn. The largest increase in global radiation over the research period was observed in Zabrze. The average annual global radiation ranged between 600–1300 kWh·m−2. Digital Elevation Models (DEM for selected districts of the Silesia region were used to calculate the theoretical potential of global solar radiation. The highest theoretical potential of global radiation was found in the district of Cieszyn, located at the highest altitude.

  6. Assessing the Performance of Global Solar Radiation Empirical ...

    In the region where solar radiation data are scarce, the next alternative method is to use solar radiation models to estimate the data needed for some applications such as simulation of crop performance and the design of solar energy conversion devices. In this paper, the validations of fifteen models for estimating monthly ...

  7. Global existence of a generalized solution for the radiative transfer equations

    Golse, F.; Perthame, B.

    1984-01-01

    We prove global existence of a generalized solution of the radiative transfer equations, extending Mercier's result to the case of a layer with an initially cold area. Our Theorem relies on the results of Crandall and Ligett [fr

  8. Earth Radiation Budget Experiment (ERBE) Data Sets for Global Environment and Climate Change Studies

    Bess, T. Dale; Carlson, Ann B.; Denn, Fredrick M.

    1997-01-01

    For a number of years there has been considerable interest in the earth's radiation budget (ERB) or energy balance, and entails making the best measurements possible of absorbed solar radiation, reflected shortwave radiation (RSW), thermal outgoing longwave radiation (OLR), and net radiation. ERB data are fundamental to the development of realistic climate models and studying natural and anthropogenic perturbations of the climate. Much of the interest and investigations in the earth's energy balance predated the age of earth-orbiting satellites (Hunt et al., 1986). Beginning in the mid 1960's earth-orbiting satellites began to play an important role in making measurements of the earth's radiation flux although much effort had gone into measuring ERB parameters prior to 1960 (House et al., 1986). Beginning in 1974 and extending until the present time, three different satellite experiments (not all operating at the same time) have been making radiation budget measurements almost continually in time. Two of the experiments were totally dedicated to making radiation budget measurements of the earth, and the other experiment flown on NOAA sun-synchronous AVHRR weather satellites produced radiation budget parameters as a by-product. The heat budget data from the AVHRR satellites began collecting data in June 1974 and have operated almost continuously for 23 years producing valuable data for long term climate monitoring.

  9. New technique for global solar radiation forecasting by simulated annealing and genetic algorithms using

    Tolabi, H.B.; Ayob, S.M.

    2014-01-01

    In this paper, a novel approach based on simulated annealing algorithm as a meta-heuristic method is implemented in MATLAB software to estimate the monthly average daily global solar radiation on a horizontal surface for six different climate cities of Iran. A search method based on genetic algorithm is applied to accelerate problem solving. Results show that simulated annealing based on genetic algorithm search is a suitable method to find the global solar radiation. (author)

  10. A hybrid computational approach to estimate solar global radiation: An empirical evidence from Iran

    Mostafavi, Elham Sadat; Ramiyani, Sara Saeidi; Sarvar, Rahim; Moud, Hashem Izadi; Mousavi, Seyyed Mohammad

    2013-01-01

    This paper presents an innovative hybrid approach for the estimation of the solar global radiation. New prediction equations were developed for the global radiation using an integrated search method of genetic programming (GP) and simulated annealing (SA), called GP/SA. The solar radiation was formulated in terms of several climatological and meteorological parameters. Comprehensive databases containing monthly data collected for 6 years in two cities of Iran were used to develop GP/SA-based models. Separate models were established for each city. The generalization of the models was verified using a separate testing database. A sensitivity analysis was conducted to investigate the contribution of the parameters affecting the solar radiation. The derived models make accurate predictions of the solar global radiation and notably outperform the existing models. -- Highlights: ► A hybrid approach is presented for the estimation of the solar global radiation. ► The proposed method integrates the capabilities of GP and SA. ► Several climatological and meteorological parameters are included in the analysis. ► The GP/SA models make accurate predictions of the solar global radiation.

  11. Prediction of Global Solar Radiation in India Using Artificial Neural Network

    Rajiv Gupta

    2016-06-01

    Full Text Available Increasing global warming and decreasing fossil fuel reserves has necessitated the use of renewable energy resources like solar energy in India. To maximize return on a solar farm, it had to be set up at a place with high solar radiation. The solar radiation values are available only for a small number of places and must be interpolated for the rest. This paper utilizes Artificial Neural Network in interpolation, by obtaining a function with input as combinations of 7 geographical and meteorological parameters affecting radiation, and output as global solar radiation. Data considered was of past 9 years for 13 Indian cities. Low error values and high coefficient of determination values thus obtained, verified that the results were accurate in terms of the original solar radiation data known. Thus, artificial neural network can be used to interpolate the solar radiation for the places of interest depending on the availability of the data.

  12. A critical review on the estimation of daily global solar radiation from sunshine duration

    Yorukoglu, Mehmet; Celik, Ali Naci

    2006-01-01

    Models such as the Angstroem-Prescott equation are used to estimate global solar radiation from sunshine duration. In the literature, researchers investigate either the goodness of the model itself or the goodness of the estimation of global solar radiation based on a set of statistical parameters such as R 2 , RMSE, MBE, MABE, MPE and MAPE. If the former is the objective, then the statistical analysis should naturally be based on H/H o - S/S o (the ratio of daily solar radiation to extraterrestrial daily solar radiation vs. the ratio of sunshine duration to day length). If the latter is investigated, then the statistical analysis should be based on H c - H m (calculated daily solar radiation vs. measured daily solar radiation). A literature survey undertaken in the present article showed that these two data sets are apt to be confused, drawing the statistical parameters to be used in assessment of the estimation model from the latter data set or the vice versa set. The statistical parameters are clearly derived from the basics for both of the data sets, and the inconsistencies caused by this confusion and other factors are exposed. A case study of the estimation models and global solar radiation estimation from sunshine duration is presented using five different models (linear, quadratic, cubic, logarithmic and exponential), which are the most common models used in the literature, based on 6 years long measured hourly global solar radiation data

  13. The Impact of Global Warming on Precipitation Patterns in Ilorin and the Hydrological Balance of the Awun Basin

    Ayanshola, Ayanniyi; Olofintoye, Oluwatosin; Obadofin, Ebenezer

    2018-03-01

    This study presents the impact of global warming on precipitation patterns in Ilorin, Nigeria, and its implications on the hydrological balance of the Awun basin under the prevailing climate conditions. The study analyzes 39 years of rainfall and temperature data of relevant stations within the study areas. Simulated data from the Coupled Global Climate model for historical and future datasets were investigated under the A2 emission scenario. Statistical regression and a Mann-Kendall analysis were performed to determine the nature of the trends in the hydrological variables and their significance levels, while a Soil and Water Assessment Tool (SWAT) was used to estimate the water balance and derive the stream flow and yield of the Awun basin. The study revealed that while minimum and maximum temperatures in Ilorin are increasing, rainfall is generally decreasing. The assessment of the trends in the water balance parameters in the basin indicates that there is no improvement in the water yield as the population increases. This may result in major stresses to the water supply in the near future.

  14. A model for calculating hourly global solar radiation from satellite data in the tropics

    Janjai, S.; Pankaew, P.; Laksanaboonsong, J.

    2009-01-01

    A model for calculating global solar radiation from geostationary satellite data is presented. The model is designed to calculate the monthly average hourly global radiation in the tropics with high aerosol load. This model represents a physical relation between the earth-atmospheric albedo derived from GMS5 satellite data and the absorption and scattering coefficients of various atmospheric constituents. The absorption of solar radiation by water vapour which is important for the tropics, was calculated from ambient temperature and relative humidity. The relationship between the visibility and solar radiation depletion due to aerosols was developed for a high aerosol load environment. This relationship was used to calculate solar radiation depletion by aerosols in the model. The total column ozone from TOMS/EP satellite was employed for the determination of solar radiation absorbed by ozone. Solar radiation from four pyranometer stations was used to formulate the relationship between the satellite band earth-atmospheric albedo and broadband earth-atmospheric albedo required by the model. To test its performance, the model was used to compute the monthly average hourly global radiation at 25 solar radiation monitoring stations in tropical areas in Thailand. It was found that the values of monthly average of hourly global radiations calculated from the model were in good agreement with those obtained from the measurements, with the root mean square difference of 10%. After the validation the model was employed to generate hourly solar radiation maps of Thailand. These maps reveal the diurnal and season variation of solar radiation over the country.

  15. A model for calculating hourly global solar radiation from satellite data in the tropics

    Janjai, S.; Pankaew, P.; Laksanaboonsong, J. [Solar Energy Research Laboratory, Department of Physics, Faculty of Science, Silpakorn University, Nakhon Pathom 73000 (Thailand)

    2009-09-15

    A model for calculating global solar radiation from geostationary satellite data is presented. The model is designed to calculate the monthly average hourly global radiation in the tropics with high aerosol load. This model represents a physical relation between the earth-atmospheric albedo derived from GMS5 satellite data and the absorption and scattering coefficients of various atmospheric constituents. The absorption of solar radiation by water vapour which is important for the tropics, was calculated from ambient temperature and relative humidity. The relationship between the visibility and solar radiation depletion due to aerosols was developed for a high aerosol load environment. This relationship was used to calculate solar radiation depletion by aerosols in the model. The total column ozone from TOMS/EP satellite was employed for the determination of solar radiation absorbed by ozone. Solar radiation from four pyranometer stations was used to formulate the relationship between the satellite band earth-atmospheric albedo and broadband earth-atmospheric albedo required by the model. To test its performance, the model was used to compute the monthly average hourly global radiation at 25 solar radiation monitoring stations in tropical areas in Thailand. It was found that the values of monthly average of hourly global radiations calculated from the model were in good agreement with those obtained from the measurements, with the root mean square difference of 10%. After the validation the model was employed to generate hourly solar radiation maps of Thailand. These maps reveal the diurnal and season variation of solar radiation over the country. (author)

  16. Establishing a Global Radiation Oncology Collaboration in Education (GRaCE)

    Turner, Sandra; Eriksen, Jesper G; Trotter, Theresa

    2015-01-01

    Representatives from countries and regions world-wide who have implemented modern competency-based radiation- or clinical oncology curricula for training medical specialists, met to determine the feasibility and value of an ongoing international collaboration. In this forum, educational leaders...... with similar goals, would provide a valuable vehicle to ensure training program currency, through sharing of resources and expertise, and enhance high quality radiation oncology education. Potential projects for the Global Radiation Oncology Collaboration in Education (GRaCE) were agreed upon...

  17. Evaluation and reconstruction of global radiation at Bílý Kříž (the Czech Republic)

    Marková, I.; Rožnovský, J.; Janouš, D.

    2003-01-01

    Evaluation of global radiation was performed at the study site of Bílý Kříž (the Moravian-Silesian Beskids Mts, the Czech Republic) during the growing seasons (May-October) in 1991-2000. Radiation conditions were characterized by daily and monthly sums of global radiation. Detailed analysis of global radiation daily sums revealed that they vary considerably with time. Average value of global radiation daily sums calculated after the whole period of seasons 1991-2000 was 13.49 MJ per square m. While seasonal course of monthly averages of global radiation daily sums corresponded to the changes of sun elevation, the average monthly sums of global radiation did not. Average seasonal sum of global radiation at the study site in 1991-2000 was 2483 +/- 141 MJ per square m. Relationship between global radiation daily sums at the Bily Kriz study site and sunshine duration at the nearby site of Lysa hora was described and linear relationship between these two characteristics was confirmed. On the basis of this determined relationship it was possible to reconstruct global radiation daily sums at the study site for a period of forty years (1961-2000). Average of global radiation daily sums calculated for the whole period of seasons from 1961 to 2000 was 9.11 MJ per square m. The highest monthly averages of global radiation daily sums were found in June and July, the lowest in October. It was confirmed that average monthly sums of global radiation did not correspond to the sun elevation even for the long period of 1961-2000. Average seasonal sum of global radiation was 2415 ñ 152 MJ.m-2 in 1961-2000. On average, 40% of extra-terrestrial solar radiation reached the study site during the growing season in 1961-2000

  18. Global solar radiation in Sierra Leone (West Africa)

    Massaquoi, J.G.M.

    1987-09-01

    A correlation equation of the Angstrom type has been developed to predict the monthly average daily global solar irradiation incident on a horizontal surface in Freetown, Sierra Leone. Measurements of the global insolation have been compared with those predicted using the equation. A good agreement (greater than 95% in most cases) was observed between the measured values and the predicted ones. (author). 15 refs, 2 tabs

  19. RAMOS - the radiation monitoring system of the Umweltforschungsinstitut Global 2000

    Exler, M.; Schmittner, W.

    2001-01-01

    The radiation early warning system RAMOS (radiation monitoring system) measures the radioactivity of the areas surrounding nuclear technical facilities (at present, around the Nuclear Power Plants Dukovany and Mochovce). Measurements are taken with Gamma-radiation devices of the type RS 03/X by the firm BITT- Technology. These devices are measuring equipment of the type Proportion-count tube with a detection range of 10 nSv/h to 10 Sv/h. The measuring stations consist of this Gamma measuring equipment, a personal computer with modem, back-up electricity devices and meteorological measuring devices. Six such measuring stations surrounding the facility comprise a complete measuring ring. The values are measured each minute. Considering the normal fluctuation in radiation measurements due to geology and weather conditions and the average background radiation, a certain alarm threshold is defined (on all stations this threshold is under 230 nSv/h). If this threshold is breached, immediately the data is transmitted through telephone lines and is received by the central office. Because of the short reaction time and low threshold, valuable time is gained for an emergency response by government agencies and the population. Official warning of the government agencies occurs after fulfilling the commendation of the Austrian Radiation Protection Commission. In the continued measurements from the end of 1994 to 2000 at NPP Dukovany and continuous measurements from NPP Mochovce from mid-1999 to the end of 2000, there was not a detection of dangerous levels of radiation were released into the atmosphere. After close examination of the measured data, different types of fluctuations could be observed - such as during the day-time period and short-term peaks after rain-fall. Detailed knowledge about trends in these fluctuations, allows an easier continual evaluation of a potential accident. The measured data is given to the public in graphic form every month via the Internet

  20. Deforestation: Can We Balance Resource Conservation with Economic Growth? Global Environmental Change Series.

    Environmental Protection Agency, Washington, DC.

    This book is the second installment in the Global Environmental Change Series that links the ecology and biology of global environmental changes with insights and information from other disciplines. This series teaches students how to gather a wide range of information from pertinent areas of study and encourages them to develop their own opinions…

  1. Balancing individual and organizational goals in global talent management : A mutual-benefits perspective

    Farndale, E.; Pai, A.; Sparrow, P.; Scullion, H.

    2014-01-01

    Drawing from the talent management and global mobility literatures, there is simultaneous pressure to address both organizational goals to place talent internationally, and individual goals of self-initiated expatriation. This raises important questions for the future of global talent management

  2. Spatio-temporal distribution of global solar radiation for Mexico using GOES data

    Bonifaz, R.; Cuahutle, M.; Valdes, M.; Riveros, D.

    2013-05-01

    Increased need of sustainable and renewable energies around the world requires studies about the amount and distribution of such types of energies. Global solar radiation distribution in space and time is a key component on order to know the availability of the energy for different applications. Using GOES hourly data, the heliosat model was implemented for Mexico. Details about the model and its components are discussed step by stem an once obtained the global solar radiation images, different time datasets (hourly, daily, monthly and seasonal) were built in order to know the spatio-temporal behavior of this type of energy. Preliminary maps of the available solar global radiation energy for Mexico are presented, the amount and variation of the solar radiation by regions are analyzed and discussed. Future work includes a better parametrization of the model using calibrated ground stations data and more use of more complex models for better results.

  3. Evaluation of long-term global radiation measurements in Denmark and Sweden

    Skalík, Lukáš; Lulkovičová, Otília; Furbo, Simon

    The climate, especially global radiation is one of the key factors influencing the energy yield of solar energy systems. In connection with planning and optimization of energy efficient buildings and solar energy systems it is important to know the climate data of the area where the buildings...... of the atmosphere, increased duration of periods without clouds and/or combination of both these effects. Twenty years of measurements from a climate station in Lyngby, Denmark show that the global radiation increase is almost 3.5 kWh/m2 per year, corresponding to a growth of 7 % for the last 20 years. The global....../systems are located. This study is based on yearly and monthly values of global radiation based on measurements from a climate station placed on the roof of building 119 at Technical University of Denmark in Kgs. Lyngby, from different Danish climate stations runned by Danish Meteorological Institute and from...

  4. Comparative analysis of different approaches to the computation of long-wave radiation balance of water air systems

    Zhukovskii, K.; Nourani, Y.; Monte, L.

    1999-01-01

    In the present paper, the net long-wave radiation balance of the water-air environmental systems is analysed on the base of several semi-empirical approaches. Various theoretical models of infrared atmospheric radiation are reviewed. Factors, affecting their behavior are considered. Special attention is paid to physical conditions under which those models are applicable. Atmospheric and net infrared radiation fluxes are computed and compared under clear and cloudy sky. Results are presented in graphical form. Conclusions are made on the applicability of models considered for evaluating infrared radiation fluxes in environmental conditions of Central Italy. On the base of present analysis Anderson's model is chosen for future calculations of heat budget of lakes in Central Italy [it

  5. Balancing radiation risks and benefits of cardiac imaging: challenges for developed countries

    Einstein, A.J.; Balter, S.; Bernheim, A.; Brenner, D.J.

    2008-01-01

    Full text: Cardiovascular disease remains the leading cause of death in the US, EU, Canada, Australia, and New Zealand, although coronary disease mortality has decreased due to improvements in prevention, diagnosis, and treatment. In many developed countries, most cardiologists now perform procedures involving radiopharmaceuticals, CT, or fluoroscopy. Their increased utilization, while contributing to improved care for patients with known or suspected heart disease, has been accompanied by a sharp increase in collective doses from medical radiation. E.g., an estimated ∼ 10% (∼ 0.6 mSv/person/y) of the collective dose to the US population is now attributed to nuclear stress tests. Radiation risk from any modality is highly dependent on patient age and gender. Cardiologists, like most non-radiologists, have had limited training in the safe use of radiation and are generally unaware of such facts. While one encouraging sign has been the development of appropriateness criteria for various cardiac imaging modalities, much work remains to advance radiological protection for the tens of millions of patients each year who receive cardiac imaging studies. Here we address current efforts to balance benefits of cardiac imaging with radiation risks, dose-reduction strategies, and future desiderata. General themes are improvements in technology, education, clinical standards, and reimbursement policies for these examinations. The vast majority of nuclear cardiology studies are performed using SPECT, and the radiopharmaceuticals used most widely are 99m Tc sestamibi and tetrofosmin, and 201 Tl. Effective doses are considerably higher for standard injected activities of 201 Tl than for 99m Tc agents, and the highest doses, ∼ 24 mSv, are associated with dual isotope (rest 201 Tl, stress 99m Tc) protocols. E.g., in the US, 1/4 of nuclear stress tests are still performed using dual isotope protocols, a practice fostered by current structuring of reimbursement. Although most

  6. Global Forest Ecosystem Structure and Function Data For Carbon Balance Research

    National Aeronautics and Space Administration — ABSTRACT: A comprehensive global database has been assembled to quantify CO2 fluxes and pathways across different levels of integration (from photosynthesis up to...

  7. Global Forest Ecosystem Structure and Function Data For Carbon Balance Research

    National Aeronautics and Space Administration — A comprehensive global database has been assembled to quantify CO2 fluxes and pathways across different levels of integration (from photosynthesis up to net...

  8. Evaluation of different models to estimate the global solar radiation on inclined surface

    Demain, C.; Journée, M.; Bertrand, C.

    2012-04-01

    Global and diffuse solar radiation intensities are, in general, measured on horizontal surfaces, whereas stationary solar conversion systems (both flat plate solar collector and solar photovoltaic) are mounted on inclined surface to maximize the amount of solar radiation incident on the collector surface. Consequently, the solar radiation incident measured on a tilted surface has to be determined by converting solar radiation from horizontal surface to tilted surface of interest. This study evaluates the performance of 14 models transposing 10 minutes, hourly and daily diffuse solar irradiation from horizontal to inclined surface. Solar radiation data from 8 months (April to November 2011) which include diverse atmospheric conditions and solar altitudes, measured on the roof of the radiation tower of the Royal Meteorological Institute of Belgium in Uccle (Longitude 4.35°, Latitude 50.79°) were used for validation purposes. The individual model performance is assessed by an inter-comparison between the calculated and measured solar global radiation on the south-oriented surface tilted at 50.79° using statistical methods. The relative performance of the different models under different sky conditions has been studied. Comparison of the statistical errors between the different radiation models in function of the clearness index shows that some models perform better under one type of sky condition. Putting together different models acting under different sky conditions can lead to a diminution of the statistical error between global measured solar radiation and global estimated solar radiation. As models described in this paper have been developed for hourly data inputs, statistical error indexes are minimum for hourly data and increase for 10 minutes and one day frequency data.

  9. Application of the modified Wheeler cap method for radiation efficiency measurement of balanced electrically small antennas in complex environment

    Zhang, Jiaying; Pivnenko, Sergey; Breinbjerg, Olav

    2010-01-01

    In this paper, application of a modified Wheeler cap method for the radiation efficiency measurement of balanced electrically small antennas is presented. It is shown that the limitations on the cavity dimension can be overcome and thus measurement in a large cavity is possible. The cavity loss...... is investigated, and a modified radiation efficiency formula that includes the cavity loss is introduced. Moreover, a modification of the technique is proposed that involves the antenna working complex environment inside the Wheeler Cap and thus makes possible measurement of an antenna close to a hand or head...

  10. Experimental analysis of the global energy balance in a DI diesel engine

    Payri González, Francisco; Olmeda González, Pablo Cesar; Martín Díaz, Jaime; Carreño, Ricardo

    2015-01-01

    The increasingly stringent internal combustion engines (ICE) emissions regulations, has led to the extended use of after-treatment systems, giving progressively more importance to the engine efficiency optimization. In this context, the experimental methodologies to perform and analyse the energy balance show as a key issue to evaluate the potential of different engine strategies aimed at the consumption optimization and the improvement paths identification. This works deals with ...

  11. Energy balance of the global photovoltaic (PV) industry--is the PV industry a net electricity producer?

    Dale, Michael; Benson, Sally M

    2013-04-02

    A combination of declining costs and policy measures motivated by greenhouse gas (GHG) emissions reduction and energy security have driven rapid growth in the global installed capacity of solar photovoltaics (PV). This paper develops a number of unique data sets, namely the following: calculation of distribution of global capacity factor for PV deployment; meta-analysis of energy consumption in PV system manufacture and deployment; and documentation of reduction in energetic costs of PV system production. These data are used as input into a new net energy analysis of the global PV industry, as opposed to device level analysis. In addition, the paper introduces a new concept: a model tracking energetic costs of manufacturing and installing PV systems, including balance of system (BOS) components. The model is used to forecast electrical energy requirements to scale up the PV industry and determine the electricity balance of the global PV industry to 2020. Results suggest that the industry was a net consumer of electricity as recently as 2010. However, there is a >50% that in 2012 the PV industry is a net electricity provider and will "pay back" the electrical energy required for its early growth before 2020. Further reducing energetic costs of PV deployment will enable more rapid growth of the PV industry. There is also great potential to increase the capacity factor of PV deployment. These conclusions have a number of implications for R&D and deployment, including the following: monitoring of the energy embodied within PV systems; designing more efficient and durable systems; and deploying PV systems in locations that will achieve high capacity factors.

  12. An algorithm to provide UK global radiation for use with models

    Hamer, P.J.C.

    1999-01-01

    Decision support systems which include crop growth models require long-term average values of global radiation to simulate future expected growth. Global radiation is rarely available as there are relatively few meteorological stations with long-term records and so interpolation between sites is difficult. Global radiation data across a good geographical spread throughout the UK were obtained and sub-divided into ‘coastal’ and ‘inland’ sites. Monthly means of global radiation (S) were extracted and analysed in relation to irradiance in the absence of atmosphere (S o ) calculated from site latitude and the time of year. The ratio S/S o was fitted to the month of the year (t) and site latitude using a nonlinear fit function in which 90% of the variance was accounted for. An algorithm is presented which provides long-term daily values of global radiation from information on latitude, time of year and whether the site is inland or close to the coast. (author)

  13. Importance of representing optical depth variability for estimates of global line-shaped contrail radiative forcing.

    Kärcher, Bernd; Burkhardt, Ulrike; Ponater, Michael; Frömming, Christine

    2010-11-09

    Estimates of the global radiative forcing by line-shaped contrails differ mainly due to the large uncertainty in contrail optical depth. Most contrails are optically thin so that their radiative forcing is roughly proportional to their optical depth and increases with contrail coverage. In recent assessments, the best estimate of mean contrail radiative forcing was significantly reduced, because global climate model simulations pointed at lower optical depth values than earlier studies. We revise these estimates by comparing the probability distribution of contrail optical depth diagnosed with a climate model with the distribution derived from a microphysical, cloud-scale model constrained by satellite observations over the United States. By assuming that the optical depth distribution from the cloud model is more realistic than that from the climate model, and by taking the difference between the observed and simulated optical depth over the United States as globally representative, we quantify uncertainties in the climate model's diagnostic contrail parameterization. Revising the climate model results accordingly increases the global mean radiative forcing estimate for line-shaped contrails by a factor of 3.3, from 3.5 mW/m(2) to 11.6 mW/m(2) for the year 1992. Furthermore, the satellite observations and the cloud model point at higher global mean optical depth of detectable contrails than often assumed in radiative transfer (off-line) studies. Therefore, we correct estimates of contrail radiative forcing from off-line studies as well. We suggest that the global net radiative forcing of line-shaped persistent contrails is in the range 8-20 mW/m(2) for the air traffic in the year 2000.

  14. Diagnostic and correction of chronic-biological mis-balances of population at radiation injuries in regions with increased radiation

    Goncharova, T.G.; Vasil'eva, G.S.

    2003-01-01

    It was shown the possibility of bio-indication of population irradiation and its rehabilitation by estimation of chronic biological mis-balances and correction realization. Investigation were accomplished on people contingent living at the former Semipalatinsk test site

  15. Balancing the benefits and risks of public-private partnerships to address the global double burden of malnutrition.

    Kraak, Vivica I; Harrigan, Paige B; Lawrence, Mark; Harrison, Paul J; Jackson, Michaela A; Swinburn, Boyd

    2012-03-01

    Transnational food, beverage and restaurant companies, and their corporate foundations, may be potential collaborators to help address complex public health nutrition challenges. While UN system guidelines are available for private-sector engagement, non-governmental organizations (NGO) have limited guidelines to navigate diverse opportunities and challenges presented by partnering with these companies through public-private partnerships (PPP) to address the global double burden of malnutrition. We conducted a search of electronic databases, UN system websites and grey literature to identify resources about partnerships used to address the global double burden of malnutrition. A narrative summary provides a synthesis of the interdisciplinary literature identified. We describe partnership opportunities, benefits and challenges; and tools and approaches to help NGO engage with the private sector to address global public health nutrition challenges. PPP benefits include: raising the visibility of nutrition and health on policy agendas; mobilizing funds and advocating for research; strengthening food-system processes and delivery systems; facilitating technology transfer; and expanding access to medications, vaccines, healthy food and beverage products, and nutrition assistance during humanitarian crises. PPP challenges include: balancing private commercial interests with public health interests; managing conflicts of interest; ensuring that co-branded activities support healthy products and healthy eating environments; complying with ethical codes of conduct; assessing partnership compatibility; and evaluating partnership outcomes. NGO should adopt a systematic and transparent approach using available tools and processes to maximize benefits and minimize risks of partnering with transnational food, beverage and restaurant companies to effectively target the global double burden of malnutrition.

  16. Global evapotranspiration over the past three decades: estimation based on the water balance equation combined with empirical models

    Zeng Zhenzhong; Piao Shilong; Yin Guodong; Peng Shushi; Lin Xin; Ciais, Philippe; Myneni, Ranga B

    2012-01-01

    We applied a land water mass balance equation over 59 major river basins during 2003–9 to estimate evapotranspiration (ET), using as input terrestrial water storage anomaly (TWSA) data from the GRACE satellites, precipitation and in situ runoff measurements. We found that the terrestrial water storage change cannot be neglected in the estimation of ET on an annual time step, especially in areas with relatively low ET values. We developed a spatial regression model of ET by integrating precipitation, temperature and satellite-derived normalized difference vegetation index (NDVI) data, and used this model to extrapolate the spatio-temporal patterns of changes in ET from 1982 to 2009. We found that the globally averaged land ET is about 604 mm yr −1 with a range of 558–650 mm yr −1 . From 1982 to 2009, global land ET was found to increase at a rate of 1.10 mm yr −2 , with the Amazon regions and Southeast Asia showing the highest ET increasing trend. Further analyses, however, show that the increase in global land ET mainly occurred between the 1980s and the 1990s. The trend over the 2000s, its magnitude or even the sign of change substantially depended on the choice of the beginning year. This suggests a non-significant trend in global land ET over the last decade. (letter)

  17. Assessment of the terrestrial water balance using the global water availability and use model WaterGAP - status and challenges

    Müller Schmied, Hannes; Döll, Petra

    2017-04-01

    The estimation of the World's water resources has a long tradition and numerous methods for quantification exists. The resulting numbers vary significantly, leaving room for improvement. Since some decades, global hydrological models (GHMs) are being used for large scale water budget assessments. GHMs are designed to represent the macro-scale hydrological processes and many of those models include human water management, e.g. irrigation or reservoir operation, making them currently the first choice for global scale assessments of the terrestrial water balance within the Anthropocene. The Water - Global Assessment and Prognosis (WaterGAP) is a model framework that comprises both the natural and human water dimension and is in development and application since the 1990s. In recent years, efforts were made to assess the sensitivity of water balance components to alternative climate forcing input data and, e.g., how this sensitivity is affected by WaterGAP's calibration scheme. This presentation shows the current best estimate of terrestrial water balance components as simulated with WaterGAP by 1) assessing global and continental water balance components for the climate period 1971-2000 and the IPCC reference period 1986-2005 for the most current WaterGAP version using a homogenized climate forcing data, 2) investigating variations of water balance components for a number of state-of-the-art climate forcing data and 3) discussing the benefit of the calibration approach for a better observation-data constrained global water budget. For the most current WaterGAP version 2.2b and a homogenized combination of the two WATCH Forcing Datasets, global scale (excluding Antarctica and Greenland) river discharge into oceans and inland sinks (Q) is assessed to be 40 000 km3 yr-1 for 1971-2000 and 39 200 km3 yr-1 for 1986-2005. Actual evapotranspiration (AET) is close to each other with around 70 600 (70 700) km3 yr-1 as well as water consumption with 1000 (1100) km3 yr-1. The

  18. Representativeness of regional and global mass-balance measurement networks (Invited)

    Cogley, J. G.; Moholdt, G.; Gardner, A. S.

    2013-12-01

    We showed in a recent publication that regional estimates of glacier mass budgets, obtained by interpolation from in-situ measurements, were markedly more negative than corresponding estimates by satellite gravimetry (GRACE) and satellite altimetry (ICESat) during 2003-2009. Examining the ICESat data in more detail, we found that in-situ records tend to be located in areas where glaciers are thinning more rapidly than as observed in their regional surroundings. Because neither GRACE nor ICESat can provide information for times before 2002-2003, and may not operate without interruption in the future, we explore possible explanations of and remedies for the identified bias in the in-situ network. Sparse spatial sampling, coupled with previously undetected spatial variability of mass balance at scales between the 10-km in-situ scale and the 350-km gravimetric scale, appears to be the leading explanation. Satisfactory remedies are not obvious. Selecting glaciers for in-situ measurement that are more representative will yield only incremental improvements. There appears to be no alternative to mass-balance modelling as a versatile tool for estimation of regional mass balance. However the meteorological data for forcing the surface components of glacier models have coarser resolution than is desirable and are themselves uncertain, especially in the remote regions where much of the glacier ice is found. Measurements of frontal (dynamic) mass changes are still difficult, and modelling of these changes remains underdeveloped in spite of recent advances. Thus research on a broad scale is called for in order to meet the challenge of producing more accurate hindcasts and projections of glacier mass budgets with fine spatial and temporal resolution.

  19. Leveraging the Global Health Service Partnership Model for Workforce Development in Global Radiation Oncology

    Omoruyi Credit Irabor

    2017-12-01

    Full Text Available A major contributor to the disparity in cancer outcome across the globe is the limited health care access in low- and middle-income countries that results from the shortfall in human resources for health (HRH, fomented by the limited training and leadership capacity of low-resource countries. In 2012, Seed Global Health teamed up with the Peace Corps to create the Global Health Service Partnership, an initiative that has introduced a novel model for tackling the HRH crises in developing regions of the world. The Global Health Service Partnership has made global health impacts in leveraging partnerships for HRH development, faculty activities and output, scholarship engagement, adding value to the learning environment, health workforce empowerment, and infrastructure development.

  20. Evaluation of Applicability of Global Solar Radiation Prediction Models for Kocaeli

    Nurullah ARSLANOĞLU

    2016-04-01

    Full Text Available Design and analyses of solar energy systems needs value of global solar radiation falling on the surface of the earth. In this study,  thirty relative sunshine duration based regression models in the literature for determining the monthly average daily global solar radiation on a horizontal surface for Kocaeli were investigated. To indicate the performance of the models, the following statistical test methods are used: mean absolute bias error (MABE, mean bias error (MBE, mean absolute percent error (MAPE, mean percent error (MPE, root mean square error (RMSE. According to the statistical performance, Lewis model (Model 23, Model-18 (Jin et al. and Model 8 (Bahel et al. showed the best estimation of the global solar radiation on a horizontal surface for Kocaeli.

  1. Estimation of radiation hazard of global 85Kr

    Vasilenko, I.Ya.; Moskalev, Yu.I.; Istomina, A.G.

    1979-01-01

    The data on sources and levels of the 85 Kr biosphere contamination are presented on the basis of generalization and analysis of literature. The potential irradiation doses for people are calculated and the biological estimation of the hazard of 85 Kr accumulation in the atmosphere up to 2050 is given taking into account the prospects for development of nuclear power engineering. The basis of the estimation is the radionuclide blastomogeneous and genetic effect. The conclusion is made that the prospects for development of nuclear power engineering do not lead to any sufficient increase in the number of malignant tumors and genetic abnormalities caused by 85 Kr radiation comparing with their natural frequency

  2. Balancing Inside and Outside Lobbying: The Political Strategies of Lobbyists at Global Diplomatic Conferences

    Hanegraaff, M.; Beyers, J.; De Bruycker, I.

    2016-01-01

    This article seeks to explain the use of inside and outside lobbying by organised interests at global diplomatic conferences. At first sight, the lobbying at these venues is puzzling as it does not seem to be a very fruitful way to acquire influence. The use of outside strategies especially is

  3. Bacillus Calmette-Guérin (BCG) vaccine: A global assessment of demand and supply balance.

    Cernuschi, Tania; Malvolti, Stefano; Nickels, Emily; Friede, Martin

    2018-01-25

    Over the past decade, several countries across all regions, income groups and procurement methods have been unable to secure sufficient BCG vaccine supply. While the frequency of stock-outs has remained rather stable, duration increased in 2014-2015 due to manufacturing issues and attracted the attention of national, regional and global immunization stakeholders. This prompted an in-depth analysis of supply and demand dynamics aiming to characterize supply risks. This analysis is unique as it provides a global picture, where previous analyses have focused on a portion of the market procuring through UN entities. Through literature review, supplier interviews, appraisal of shortages, stock-outs and historical procurement data, and through demand forecasting, this analysis shows an important increase in global capacity in 2017: supply is sufficient to meet forecasted BCG vaccine demand and possibly buffer market shocks. Nevertheless, risks remain mainly due to supply concentration and limited investment in production process improvements, as well as inflexibility in demand. Identification of these market risks will allow implementation of risk-mitigating interventions in three areas: (1) enhancing information sharing between major global health actors, countries and suppliers, (2) identifying interests and incentives to expand product registration and investment in the BCG manufacturing process, and (3) working with countries for tighter vaccine management. Copyright © 2017. Published by Elsevier Ltd.

  4. Balancing friends and foes : Explaining advocacy styles at global diplomatic conferences

    Beyers, J.; Hanegraaff, M.

    The growing attempts by non-state interests to influence global policy processes has attracted much scholarly interest in recent years. One important question thereby is what characterizes and explains the interactions of non-state advocates with policymakers. In order to clarify this matter, we

  5. Global carbon - nitrogen - phosphorus cycle interactions: A key to solving the atmospheric CO2 balance problem?

    Peterson, B. J.; Mellillo, J. M.

    1984-01-01

    If all biotic sinks of atmospheric CO2 reported were added a value of about 0.4 Gt C/yr would be found. For each category, a very high (non-conservative) estimate was used. This still does not provide a sufficient basis for achieving a balance between the sources and sinks of atmospheric CO2. The bulk of the discrepancy lies in a combination of errors in the major terms, the greatest being in a combination of errors in the major terms, the greatest being in the net biotic release and ocean uptake segments, but smaller errors or biases may exist in calculations of the rate of atmospheric CO2 increase and total fossil fuel use as well. The reason why biotic sinks are not capable of balancing the CO2 increase via nutrient-matching in the short-term is apparent from a comparison of the stoichiometry of the sources and sinks. The burning of fossil fuels and forest biomass releases much more CO2-carbon than is sequestered as organic carbon.

  6. Trapped-Ion Quantum Logic with Global Radiation Fields.

    Weidt, S; Randall, J; Webster, S C; Lake, K; Webb, A E; Cohen, I; Navickas, T; Lekitsch, B; Retzker, A; Hensinger, W K

    2016-11-25

    Trapped ions are a promising tool for building a large-scale quantum computer. However, the number of required radiation fields for the realization of quantum gates in any proposed ion-based architecture scales with the number of ions within the quantum computer, posing a major obstacle when imagining a device with millions of ions. Here, we present a fundamentally different approach for trapped-ion quantum computing where this detrimental scaling vanishes. The method is based on individually controlled voltages applied to each logic gate location to facilitate the actual gate operation analogous to a traditional transistor architecture within a classical computer processor. To demonstrate the key principle of this approach we implement a versatile quantum gate method based on long-wavelength radiation and use this method to generate a maximally entangled state of two quantum engineered clock qubits with fidelity 0.985(12). This quantum gate also constitutes a simple-to-implement tool for quantum metrology, sensing, and simulation.

  7. A fuzzy regression with support vector machine approach to the estimation of horizontal global solar radiation

    Baser, Furkan; Demirhan, Haydar

    2017-01-01

    Accurate estimation of the amount of horizontal global solar radiation for a particular field is an important input for decision processes in solar radiation investments. In this article, we focus on the estimation of yearly mean daily horizontal global solar radiation by using an approach that utilizes fuzzy regression functions with support vector machine (FRF-SVM). This approach is not seriously affected by outlier observations and does not suffer from the over-fitting problem. To demonstrate the utility of the FRF-SVM approach in the estimation of horizontal global solar radiation, we conduct an empirical study over a dataset collected in Turkey and applied the FRF-SVM approach with several kernel functions. Then, we compare the estimation accuracy of the FRF-SVM approach to an adaptive neuro-fuzzy system and a coplot supported-genetic programming approach. We observe that the FRF-SVM approach with a Gaussian kernel function is not affected by both outliers and over-fitting problem and gives the most accurate estimates of horizontal global solar radiation among the applied approaches. Consequently, the use of hybrid fuzzy functions and support vector machine approaches is found beneficial in long-term forecasting of horizontal global solar radiation over a region with complex climatic and terrestrial characteristics. - Highlights: • A fuzzy regression functions with support vector machines approach is proposed. • The approach is robust against outlier observations and over-fitting problem. • Estimation accuracy of the model is superior to several existent alternatives. • A new solar radiation estimation model is proposed for the region of Turkey. • The model is useful under complex terrestrial and climatic conditions.

  8. Los sistemas silvopastoriles y el calentamiento global: un balance de emisiones

    Johnny Montenegro

    2002-01-01

    Full Text Available Se realiz6 un balance de emisiones de ga- ses con efecto invernadero en Sistemas Silvopas- toriles (SSP ubicados en 3 diferentes zonas de vida. Se determin6 la emisi6n de di6xido de car- bono (CO2 y de 6xido nitroso (N2O en forma de gas, se cuantific6la cantidad de carbono (C fija- do en el suelo y en el componente arb6reo, y se humiestim6 la emisi6n de metano (CH4 producido por los bovinos. Se realiz6 analisis de variancia de correlaci6n lineal entre las distintas varia- bles evaluadas. El SSP ubicado en el Bosque Montano Bajo, present6 41,2 ton C ha-1 fijado valores de emisi6n neta (EN de 5,65 y 6,87 kg de N y C ha-Iafio-1 respectivamente. En el com- ponente arb6reo se determin6 una fijaci6n de 229 kg C ha-Iano-I, la emisi6n de CH4 fue de 360 kg ha-Iano-I. El balance anual refleja una emisi6n neta de 2418 kg de C ha-Iano-l. En la zo- na de vida Bosque Premontano muy Humedo, en eISSPsedetermin6enelsuel020,9tonCha-l,sien- do la EN de -1,58 y 3,51 kg de N y C ha-Iano-l, res- pectivamente. El C fijado por el componente ar- b6reo fue 313 kg C ha-Iafio-l; la emisi6n de CH4 highfue de 654 kg ha-Iano-I. El balance anual presen- ecosyst6 una emisi6n neta de 3911 kg de C ha-Iano- En el SSP ubicado en el Bosque Humedo Tropi- cal, se determin6 42,8 ton C ha-Iafio-I. La EN correspondi6 al,16 y 3,99 kg de N y C ha-Iano-l, estirespectivamente. El C fijado par ano en el compo- nente arb6reo rue de 313 kg C ha-l, la ernisi6n de CH4fue de 183 kg ha-Iano-l. El balance anual pre- sent6 una emisi6n neta de 418 kg de C ha-lano-l. En los 3 SSP evaluados las emisiones de gases con efecto invemadero fueron mayores que el C fijado, incidiendo en ello principal mente el CH4; sin embargo, es factible disrninuir las emisiones de este gas e incrementar la cantidad de C fijado, ya que existe la tecnologia para ella, 10 cual afectaria positivamente el balance final obteniendose SSP evamas amigables con el ambiente.

  9. Comparison of 37 months global net radiation flux derived from PICARD-BOS over the same period observations of CERES and ARGO

    Zhu, Ping; Wild, Martin

    2016-04-01

    The absolute level of the global net radiation flux (NRF) is fixed at the level of [0.5-1.0] Wm-2 based on the ocean heat content measurements [1]. The space derived global NRF is at the same order of magnitude than the ocean [2]. Considering the atmosphere has a negligible effects on the global NRF determination, the surface global NRF is consistent with the values determined from space [3]. Instead of studying the absolute level of the global NRF, we focus on the interannual variation of global net radiation flux, which were derived from the PICARD-BOS experiment and its comparison with values over the same period but obtained from the NASA-CERES system and inferred from the ocean heat content survey by ARGO network. [1] Allan, Richard P., Chunlei Liu, Norman G. Loeb, Matthew D. Palmer, Malcolm Roberts, Doug Smith, and Pier-Luigi Vidale (2014), Changes in global net radiative imbalance 1985-2012, Geophysical Research Letters, 41 (no.15), 5588-5597. [2] Loeb, Norman G., John M. Lyman, Gregory C. Johnson, Richard P. Allan, David R. Doelling, Takmeng Wong, Brian J. Soden, and Graeme L. Stephens (2012), Observed changes in top-of-the-atmosphere radiation and upper-ocean heating consistent within uncertainty, Nature Geoscience, 5 (no.2), 110-113. [3] Wild, Martin, Doris Folini, Maria Z. Hakuba, Christoph Schar, Sonia I. Seneviratne, Seiji Kato, David Rutan, Christof Ammann, Eric F. Wood, and Gert Konig-Langlo (2015), the energy balance over land and oceans: an assessment based on direct observations and CMIP5 climate models, Climate Dynamics, 44 (no.11-12), 3393-3429.

  10. Assessment of global cloud datasets from satellites: Project and database initiated by the GEWEX radiation panel

    Stubenrauch , C.J.; Rossow , W.B.; Kinne , S.; Ackerman , S.; Cesana , G.; Chepfer , H.; Di Girolamo , L.; Getzewich , B.; Guignard , A.; Heidinger , A.; Maddux , B.C.; Menzel , W.P.; Minnis , P.; Pearl , C.; Platnick , S.

    2013-01-01

    International audience; The Global Energy and Water Cycle Experiment (GEWEX) Radiation Panel initiated the GEWEX Cloud Assessment in 2005 to compare available, global, long-term cloud data products with the International Satellite Cloud Climatology Project (ISCCP). The GEWEX Cloud Assessment database included cloud properties retrieved from different satellite sensor measurements, taken at various local times and over various time periods. The relevant passive satellite sensors measured radia...

  11. THE REGULARITIES OF THE SPACE-TEMPORAL DISTRIBUTION OF THE RADIATION BALANCE OF THE UNDERLYING SURFACE IN ARAKS BASIN ON MOUNTAINOUS TERRITORY OF THE REPUBLIC OF ARMENIA

    V. G. Margaryan

    2017-12-01

    Full Text Available The regularities of the space-temporal distribution of the radiation balance of the underlying surface for the conditions of the mountainous territory of the Republic of Armenia were discussed and analyzed.

  12. Radiation effects on man health, environment, safety, security. Global Chernobyl mapping

    Bebeshko, V.; Bazyka, D.; Volovik, S.; Loganovsky, K.; Sushko, V.; Siedow, J.; Cohen, H.; Ginsburg, G.; Chao, N.; Chute, J.

    2007-01-01

    Complete text of publication follows. Objectives: Ionizing radiation is a primordial terrestrial and extraterrestrial background and archetypal environmental stress-factor for life origin, evolution, and existence. We all live in radiation world inevitably involving nuclear energy production, nuclear weapon, nuclear navy, radioactive waste, pertinent medical diagnostics and treatment, etc with connected certain probability of relevant accidents and terrorist attack, space and jet travels, high natural background radiation, etc - actual and potential sources of radiation exposures and effects. State-of- the art integral fundamental research on radiation effects on man health, environment, safety, and security (REMHESS) is nowadays paramount necessity and challenge. Methods and results: In given generalized conceptual framework unique 20 years Chernobyl multidimensional research and databases for radiation effects on man's all organism systems represent invaluable original basis and resources for mapping Chernobyl data and REMHESS challenge. Granted by DOE brand new Chernobyl Research and Service Project based on 'Sarcophagus-II' (Object 'Shelter') workers only one in radiation history baseline cohort, corresponding biorepository prospective dynamic data, integrated conceptual database system, and 'state of the art' 'omics' (genomics, proteomics, metabolomics) analysis is designed specifically for coherent addressing global REMHESS problems. In this connection 'Sarcophagus-II' is only one unique universal model. Conclusions: The fundamental goals of novel strategic Project and global Chernobyl mapping are to determine specific 'omics' signatures of radiation for man depending of exposure peculiarity to understand ultimate molecular mechanisms of radiation effects, gene environment interactions, etiology of organisms systems disorders and diseases, and to develop new biomarkers and countermeasures to protect man health in the framework of global REMHESS challenge

  13. Finding the missing plastic -resolving the global mass (im)balance for plastic pollution in the ocean

    Wilcox, C.; van Sebille, E.

    2016-02-01

    Several global studies have attempted to estimate the standing stock of plastic debris in the oceans at the global scale. However, recent work estimating the amount lost from land on an annual basis suggests that the standing stock should be several orders of magnitude larger than the global estimates. We investigate the role of coastal deposition within the first few weeks after plastic enters the ocean and very near its sources, one of the hypothesized sinks for the missing plastic in this mass balance. We utilize a continental scale dataset of plastics collected along Australia's coast and in the offshore regions together with models of plastic release and transport based on Lagrangian tracking to investigate the role of local deposition in the coastal environment. Our models predict that the vast majority of positively buoyant plastic is deposited within a very short distance from its release point, with only a small fraction escaping into the open ocean. These predictions match our coastal and offshore observations, providing clear evidence that this mechanism of immediate coastal deposition is, at least in part, driving the apparent mismatch between coastal emissions and the standing stock in the ocean.

  14. Effective aerosol optical depth from pyranometer measurements of surface solar radiation (global radiation) at Thessaloniki, Greece

    Lindfors, A. V.; Kouremeti, N.; Arola, A.; Kazadzis, S.; Bais, A. F.; Laaksonen, A.

    2013-01-01

    Pyranometer measurements of the solar surface radiation (SSR) are available at many locations worldwide, often as long time series covering several decades into the past. These data constitute a potential source of information on the atmospheric aerosol load. Here, we present a method for estimating the aerosol optical depth (AOD) using pyranometer measurements of the SSR together with total water vapor column information. The method, which is based on radiative transfer simulations, w...

  15. Global Sensitivity of Simulated Water Balance Indicators Under Future Climate Change in the Colorado Basin

    Bennett, Katrina E.; Urrego Blanco, Jorge R.; Jonko, Alexandra; Bohn, Theodore J.; Atchley, Adam L.; Urban, Nathan M.; Middleton, Richard S.

    2018-01-01

    The Colorado River Basin is a fundamentally important river for society, ecology, and energy in the United States. Streamflow estimates are often provided using modeling tools which rely on uncertain parameters; sensitivity analysis can help determine which parameters impact model results. Despite the fact that simulated flows respond to changing climate and vegetation in the basin, parameter sensitivity of the simulations under climate change has rarely been considered. In this study, we conduct a global sensitivity analysis to relate changes in runoff, evapotranspiration, snow water equivalent, and soil moisture to model parameters in the Variable Infiltration Capacity (VIC) hydrologic model. We combine global sensitivity analysis with a space-filling Latin Hypercube Sampling of the model parameter space and statistical emulation of the VIC model to examine sensitivities to uncertainties in 46 model parameters following a variance-based approach. We find that snow-dominated regions are much more sensitive to uncertainties in VIC parameters. Although baseflow and runoff changes respond to parameters used in previous sensitivity studies, we discover new key parameter sensitivities. For instance, changes in runoff and evapotranspiration are sensitive to albedo, while changes in snow water equivalent are sensitive to canopy fraction and Leaf Area Index (LAI) in the VIC model. It is critical for improved modeling to narrow uncertainty in these parameters through improved observations and field studies. This is important because LAI and albedo are anticipated to change under future climate and narrowing uncertainty is paramount to advance our application of models such as VIC for water resource management.

  16. China's energy statistics in a global context: A methodology to develop regional energy balances for East, Central and West China

    Mischke, Peggy

    2013-01-01

    for research and policy analysis. An improved understanding of the quality and reliability of Chinese economic and energy data is becoming more important to to understanding global energy markets and future greenhouse gas emissions. China’s national statistical system to track such changes is however still...... developing and, in some instances, energy data remain unavailable in the public domain. This working paper discusses China’s energy and economic statistics in view of identifying suitable indicators to develop a simplified regional energy systems for China from a variety of publicly available data. As China......’s national statistical system continuous to be debated and criticised in terms of data quality, comparability and reliability, an overview of the milestones, status and main issues of China’s energy statistics is given. In a next step, the energy balance format of the International Energy Agency is used...

  17. Inter-comparison of different models for estimating clear sky solar global radiation for the Negev region of Israel

    Ianetz, Amiran; Lyubansky, Vera; Setter, Ilan; Kriheli, Boris; Evseev, Efim G.; Kudish, Avraham I.

    2007-01-01

    Solar global radiation is a function of solar altitude, site altitude, albedo, atmospheric transparency and cloudiness, whereas solar global radiation on a clear day is defined such that it is a function of all the abovementioned parameters except cloudiness. Consequently, analysis of the relative magnitudes of solar global radiation and solar global radiation on a clear day provides a platform for studying the influence of cloudiness on solar global radiation. The Iqbal filter for determining the day type has been utilized to calculate the monthly average clear day solar global radiation at three sites in the Negev region of Israel. An inter-comparison between four models for estimating clear sky solar global radiation at the three sites was made. The relative accuracy of the four models was determined by comparing the monthly average daily clear sky solar global radiation to that determined using the Iqbal filter. The analysis was performed on databases consisting of measurements made during the time interval of January 1991 to December 2004. The monthly average daily clear sky solar global radiation determined by the Berlynd model was found to give the best agreement with that determined using the Iqbal filter. The Berlynd model was then utilized to calculate a daily clear day index, K c , which is defined as the ratio of the daily solar global radiation to the daily clear day solar global radiation. It is suggested that this index be used as an indication of the degree of cloudiness. Linear regression analysis was performed on the individual monthly databases for each site to determine the correlation between the daily clear day index and the daily clearness index, K T

  18. A Linear Regression Model for Global Solar Radiation on Horizontal Surfaces at Warri, Nigeria

    Michael S. Okundamiya

    2013-10-01

    Full Text Available The growing anxiety on the negative effects of fossil fuels on the environment and the global emission reduction targets call for a more extensive use of renewable energy alternatives. Efficient solar energy utilization is an essential solution to the high atmospheric pollution caused by fossil fuel combustion. Global solar radiation (GSR data, which are useful for the design and evaluation of solar energy conversion system, are not measured at the forty-five meteorological stations in Nigeria. The dearth of the measured solar radiation data calls for accurate estimation. This study proposed a temperature-based linear regression, for predicting the monthly average daily GSR on horizontal surfaces, at Warri (latitude 5.020N and longitude 7.880E an oil city located in the south-south geopolitical zone, in Nigeria. The proposed model is analyzed based on five statistical indicators (coefficient of correlation, coefficient of determination, mean bias error, root mean square error, and t-statistic, and compared with the existing sunshine-based model for the same study. The results indicate that the proposed temperature-based linear regression model could replace the existing sunshine-based model for generating global solar radiation data. Keywords: air temperature; empirical model; global solar radiation; regression analysis; renewable energy; Warri

  19. Estimation of global solar radiation on horizontal surfaces in Jeddah, Saudi Arabia

    El-Sebaii, A.A.; Al-Ghamdi, A.A.; Al-Hazmi, F.S.; Faidah, Adel S.

    2009-01-01

    The measured data of global solar radiation on a horizontal surface, as well as the number of sunshine hours, mean daily ambient temperature, maximum and minimum ambient temperatures, relative humidity and amount of cloud cover, for Jeddah (latitude 21 deg. 42'37''N, longitude 39 deg. 11'12''E), Saudi Arabia for the period 1996-2006 are analyzed. The data are divided into two sets. The sub-data set 1 (1996-2004) are employed to develop empirical correlations between the monthly average of daily global solar radiation fraction (H/H 0 ) and various meteorological parameters. The nonlinear Angstroem type model developed by Sen and the trigonometric function model proposed by Bulut and Bueyuekalaca are also evaluated. New empirical constants for these two models have been obtained for Jeddah. The sub-data set 2 (2005, 2006) are then used to evaluate the derived correlations. Comparisons between measured and calculated values of H have been performed. It is indicated that, the Sen and Bulut and Bueyuekalaca models satisfactorily describe the horizontal global solar radiation for Jeddah. All the proposed correlations are found to be able to predict the annual average of daily global solar radiation with excellent accuracy. Therefore, the long term performance of solar energy devices can be estimated.

  20. Modelling, interpolation and stochastic simulation in space and time of global solar radiation

    Bechini, L.; Ducco, G.; Donatelli, M.; Stein, A.

    2000-01-01

    Global solar radiation data used as daily inputs for most cropping systems and water budget models are frequently available from only a few weather stations and over short periods of time. To overcome this limitation, the Campbell–Donatelli model relates daily maximum and minimum air temperatures to

  1. GLOBAL SOLAR RADIATION INTERCEPTION BY GRAPEVINES TRAINED TO A VERTICAL TRELLIS SYSTEM

    CLAUDIA GUIMARÃES CAMARGO CAMPOS

    2016-01-01

    Full Text Available ABSTRACT In this paper we assess the utilization of radiant energy in the growing of grapevines (Cabernet Sauvignon trained to a vertical trellis system, and estimate the global solar radiation interception taking into account the physical characteristics of the training system at different phenological stages. The experiment was based on daily measurements of global solar radiation made by an automatic weather station placed at the vineyard of a winery located in the municipality of São Joaquim, in the southern Brazilian State of Santa Catarina (Villa Francioni winery, 28º 15’ 14” S, 49º 57’ 02” W, 1294m a.s.l.. Growth and phenological development of the shoots were evaluated. The global solar radiation is intercepted by the canopy (trained to a vertical trellis system in different orientations and the accumulated total is slightly greater on the east than on the west face of the canopy, especially after flowering. The daily variability of global solar radiation intercepted by the canopy is greater after flowering. The accumulated solar energy incident on the canopy increases until the onset of ripening. From the results, vineyards trained to a vertical trellis system in the north-south direction provide favorable sunlight exposure to leaves and fruits and are promising in quality and productivity.

  2. Using probabilistic finite automata to simulate hourly series of global radiation

    Mora-Lopez, L. [Universidad de Malaga (Spain). Dpto. Lenguajes y Computacion; Sidrach-de-Cardona, M. [Universidad de Malaga (Spain). Dpto. Fisica Aplicada II

    2003-03-01

    A model to generate synthetic series of hourly exposure of global radiation is proposed. This model has been constructed using a machine learning approach. It is based on the use of a subclass of probabilistic finite automata which can be used for variable-order Markov processes. This model allows us to represent the different relationships and the representative information observed in the hourly series of global radiation; the variable-order Markov process can be used as a natural way to represent different types of days, and to take into account the ''variable memory'' of cloudiness. A method to generate new series of hourly global radiation, which incorporates the randomness observed in recorded series, is also proposed. As input data this method only uses the mean monthly value of the daily solar global radiation. We examine if the recorded and simulated series are similar. It can be concluded that both series have the same statistical properties. (author)

  3. The global distribution of giant radiating dike swarms on Venus: Implications for the global stress state

    Grosfils, Eric B.; Head, James W.

    1994-01-01

    Magellan radar data of Venus reveal 163 large radial lineament systems composed of graben, fissure, and fracture elements. On the basis of their structure, plan view geometry, and volcanic associations, at least 72% are interpreted to have formed primarily through subsurface dike swarm emplacement, the remainder through uplift or a combination of these two mechanisms. The population of swarms is used to determine regional and global stress orientation. The stress configuration recorded from 330-210 deg E (Aphrodite Terra) is best explained by isostatic compensation of existing long wavelength topography or coupling between mantle flow and the lithosphere. The rest are correlated with concentrations of rifting and volcanism in the Beta-Atla-Themis region. The global stress field on Venus is different than that of Earth, where plate boundary forces dominate.

  4. Balancing radiation benefits and risks: The needs of an informed public

    1994-04-01

    The American public`s perceptions regarding ionizing radiation do not always conform to or correlate with scientific evidence. The ultimate purpose of this coordinated Federal effort and report is to increase the public`s knowledge of the benefits and risks associated with ionizing radiation. This report is divided into five sections. The first section, Introduction, discusses the public`s knowledge of radiation, their perceptions of benefits versus risks, and the Federal government`s role in public education. The section also outlines the charge to the Subpanel. Radiation Issues and Public Reactions discusses several radiation issues important to Federal agencies for which public education programs need to be established or enhanced. Federal Programs describes Federal agencies with public education programs on radiation and the nature of the programs they support. Education Issues and Federal Strategies explores the elements identified by the Subpanel as critical to the development and implementation of an effective Federal program in the area of public education on radiation issues and nuclear technologies. An important issue repeatedly brought up during the public sector presentations to the Subpanel was the perceived lack of Federal credibility on radiation issues in the eyes of the public. To some degree, this concern was factored into all of the recommendations developed by the subpanel. The issues discussed in this section include the fragmented nature of Federal radiation programs and the need to improve credibility, promote agency responsiveness, and support the enhancement of scientific literacy. Finally, under Recommendations, the Subpanel discusses its overall findings and conclusions.

  5. Balancing radiation benefits and risks: The needs of an informed public

    1994-04-01

    The American public's perceptions regarding ionizing radiation do not always conform to or correlate with scientific evidence. The ultimate purpose of this coordinated Federal effort and report is to increase the public's knowledge of the benefits and risks associated with ionizing radiation. This report is divided into five sections. The first section, Introduction, discusses the public's knowledge of radiation, their perceptions of benefits versus risks, and the Federal government's role in public education. The section also outlines the charge to the Subpanel. Radiation Issues and Public Reactions discusses several radiation issues important to Federal agencies for which public education programs need to be established or enhanced. Federal Programs describes Federal agencies with public education programs on radiation and the nature of the programs they support. Education Issues and Federal Strategies explores the elements identified by the Subpanel as critical to the development and implementation of an effective Federal program in the area of public education on radiation issues and nuclear technologies. An important issue repeatedly brought up during the public sector presentations to the Subpanel was the perceived lack of Federal credibility on radiation issues in the eyes of the public. To some degree, this concern was factored into all of the recommendations developed by the subpanel. The issues discussed in this section include the fragmented nature of Federal radiation programs and the need to improve credibility, promote agency responsiveness, and support the enhancement of scientific literacy. Finally, under Recommendations, the Subpanel discusses its overall findings and conclusions

  6. First characterization and comparison of TEB model simulations with in situ measurements regarding radiation balance in a single urban canyon at the BOKU site (Vienna)

    Oswald, Sandro; Trimmel, Heidelinde; Revesz, Michael; Nadeem, Imran; Masson, Valéry; Weihs, Philipp

    2017-04-01

    According to the World Health Organization more than half of the world population lives in a city since 2010. Predictions foresee that by 2030 six out of ten people will live in an urban area. As a result, many cities are expanding in size. Almost 10% of all urban dwellers live in megacities (defined according to UN HABITAT as a city with a population of more than 10 million). There are several effects in cities which strongly influence human health. Visible influences like the severe emissions of air pollutants by industry and traffic (e.g. Mayer H., 1999, Grimmond et al., 2010) are obvious to people but thermal stress in urban areas is only recently recognized for its strong devastating effect on human health. As a consequence, the urban environment virtually influences all weather parameters that have an impact on human comfort and thermal stress. Within this study, we investigate effects of city growth and the development of outlying districts on the local climate of Vienna. We focus particularly on the influence of urban heat island and consequent the risk for heat related illnesses or thermal stress for people. To quantify radiation balance and other important meteorological factors, we performed an extensive field campaign with three types of net radiometer in three different heights at BOKU site in August 2016. The first results indicated a strong correlation (ρ=0.96) between the Town Energy Balance (TEB) model and the measurements of the top net radiometer regarding radiation balance at roof level, meanwhile the TEB results are slightly underestimated. Further check if the measurements are reasonable, a comparison of the input values (global and direct solar radiation) for the TEB simulation with Secondary Standard measurements of ARAD site Wien Hohe Warte shows a deviation under 2% concerning interquartile range on clear sky days. The next steps will enclose TEB simulations, coupled with the mesoscale Weather Research and Forecasting (WRF) model, for

  7. Sunshine-based estimation of global solar radiation on horizontal surface at Lake Van region (Turkey)

    Duzen, Hacer; Aydin, Harun

    2012-01-01

    Highlights: ► The global solar radiation at Lake Van region is estimated. ► This study is unique for the Lake Van region. ► Solar radiation around Lake Van has the highest value at the east-southeast region. ► The annual average solar energy potential is obtained as 750–2458 kWh/m 2 . ► Results can be used to estimate evaporation. - Abstract: In this study several sunshine-based regression models have been evaluated to estimate monthly average daily global solar radiation on horizontal surface of Lake Van region in the Eastern Anatolia region in Turkey by using data obtained from seven different meteorological stations. These models are derived from Angström–Prescott linear regression model and its derivatives such as quadratic, cubic, logarithmic and exponential. The performance of this regression models were evaluated by comparing the calculated clearness index and the measured clearness index. Several statistical tests were used to control the validation and goodness of the regression models in terms of the coefficient of determination, mean percent error, mean absolute percent error, mean biased error, mean absolute biased error, root mean square error and t-statistic. The results of all the regression models are within acceptable limits according to the statistical tests. However, the best performances are obtained by cubic regression model for Bitlis, Gevaş, Hakkari, Muş stations and by quadratic regression model for Malazgirt, Tatvan and Van stations to predict global solar radiation. The spatial distributions of the monthly average daily global solar radiation around the Lake Van region were obtained with interpolation of calculated solar radiation data that acquired from best fit models of the stations. The annual average solar energy potential for Lake Van region is obtained between 750 kWh/m 2 and 2485 kWh/m 2 with annual average of 1610 kWh/m 2 .

  8. The effect of aerosol on closure of the regionale short-wave radiation balance

    Henzing JS; Knap WH; Stammes P; ten Brink HM; Kos GPA; Even A; Swart DPJ; Bergwerff JP; Apituley A; NOP

    2001-01-01

    IPPC reports the aerosol radiative forcing per major aerosol category, like sulphate and fossil fuel derived carbon. Part of this carbon is reflective and part of the material (black carbon "soot") absorbs radiation. We find that in the Netherlands sulphate contributes some 30% to the

  9. An overview of global solar radiation measurements in Ghardaia area, south Algeria

    Gairaa, Kacem; Bakelli, Yahia [Applied Research Unit for Renewables Energies, Ouargla Road, Ghardaia (Algeria)

    2011-07-01

    This paper presents an overview of actual solar radiation data measurements in Ghardaia site (32.360 N, 3.810 W, 450 m above MSL). Global solar radiation and surface temperatures were measured and analyzed for one complete year from 1 January-31December 2005. The data thus recorded are compared with corresponding data of the 22-year average of NASA's surface meteorology and solar energy-model. Hourly, daily and monthly solar radiation was made from five-minute recorded by EKO Pyranometer. The highest measured daily and monthly mean solar radiation was found to be 369 and 326 (W/m2), and the highest five minute averaged solar radiation values up to 1268 (W/m2) were observed in the summer season from May to September, and the yearly average daily energy input was 21.83 (MJ/m2/day). Besides the global solar radiation, the daily and monthly average temperature variations are discussed. The collected data indicate that Ghardaia has a strong potential for solar energy applications.

  10. Building global and diffuse solar radiation series and assessing decadal trends in Girona (NE Iberian Peninsula)

    Calbó, Josep; González, Josep-Abel; Sanchez-Lorenzo, Arturo

    2017-08-01

    Measurement of solar radiation was initiated in Girona, northeast of the Iberian Peninsula, in the late 1980s. Initially, two pyranometers were installed, one of them equipped with a shadowband for measuring the diffuse component. Two other pyranometers currently exist, both ventilated and one of them shadowed, with a sphere, and a pyrheliometer for measuring direct radiation. Additional instruments for other shortwave and longwave components, clouds, and atmospheric aerosols have been installed in recent years. The station is subject to daily inspection, data are saved at high temporal resolution, and instruments are periodically calibrated, all in accordance with the directions of the Baseline Surface Radiation Network. The present paper describes how the entire series of global solar radiation (1987-2014) and diffuse radiation (1994-2014) were built, including the quality control process. Appropriate corrections to the diffuse component were made when a shadowband was employed to make measurements. Analysis of the series reveals that annual mean global irradiance presents a statistically significant increase of 2.5 W m-2 (1.4 %) decade-1 (1988-2014 period), mainly due to what occurs in summer (5.6 W m-2 decade-1). These results constitute the first assessment of solar radiation trends for the northeastern region of the Iberian Peninsula and are consistent with trends observed in the regional surroundings and also by satellite platforms, in agreement with the global brightening phenomenon. Diffuse radiation has decreased at -1.3 W m-2 (-2 %) decade-1 (1994-2014 period), which is a further indication of the reduced cloudiness and/or aerosol load causing the changes.

  11. European social model and challenges of globalization: searching the ways of balancing of the needs of the economy and societ

    N.P. Topishko

    2015-03-01

    Full Text Available The features of the fundamental models of social policy in the EU and social procection system as one of its mechanisms has been characterized. The changes in the division of responsibility between the subjects of social partnership in providing social protection is analyzed. Special attention paid to the increasing socio-economic contradictions in terms of global transformations and social orientation of stabilization measures by governments. The principles on which reform is carried taxation and social welfare systems is observed. It is also described the change in the tax system in terms of finding ways to fiscal consolidation, including the measures of increasing rate of progressivity of the tax system and fiscal role of indirect taxes, broadening the tax base, increase the tax burden on passive income. Approaches to adopt the European model of social protection to globalization and the rise of the economic crisis has been investigated. The ways to achieve a balance between the social functions of the state and the level of financial supportis outlined.

  12. Effects of anthropogenic aerosol particles on the radiation balance of the atmosphere. Einfluss anthropogener Aerosolteilchen auf den Strahlungshaushalt der Atmosphaere

    Newiger, M

    1985-01-01

    The influence of aerosol particles is assessed on the basis of the changes in the climate parameters ''albedo'' and ''neutron flux''. Apart from the directly emitted particles, particles formed in the atmosphere as a result of SO/sub 2/ emissions are investigated. The model of aerosol effects on the radiation field takes account of the feedback with the microphysical parameters of the clouds. In the investigation, given particle concentrations were recalculated for three size classes using a two-dimensional transport model. The particle size distribution is described by a modified power function. Extreme-value estimates are made because the absorption capacity of anthropogenic particles is little known. A comparison of the climatic effects of anthropogenic activities shows that aerosol particles and SO/sub 2/ emissions have opposite effects on the radiation balance. (orig./PW).

  13. The internet and contemporary visual culture: balancing aesthetics and politics in museums during the global era

    Christine Bernier

    2013-06-01

    Full Text Available This essay looks at the use made by several museums of highly advanced technological and communication tools. An examination of a number of recent media events highlights the important place assigned by museums to new exhibition platforms and techniques, such as virtual exhibitions and extremely high-resolution reproductions. Through an analysis of several recent cases that illustrate how controversies sparked by contemporary artworks are handled, I consider how museums deal with politics and aesthetics in their mediation of artworks in the global era. Particular attention is paid to the Internet presentation of a work by the contemporary artist Chris Ofili entitled No Woman, No Cry , which was selected by Tate Britain to be part of the Google Art Project. A review of several other events dating from 2011 reveals how in the context of the Internet museums pursue the same principles they have long been applying in their exhibition galleries and communications with the public. This essay also casts light on the fundamentally new methods that can be employed by websites in the presentation of images in general and artworks in particular.

  14. Global Surface Net-Radiation at 5 km from MODIS Terra

    Manish Verma

    2016-09-01

    Full Text Available Reliable and fine resolution estimates of surface net-radiation are required for estimating latent and sensible heat fluxes between the land surface and the atmosphere. However, currently, fine resolution estimates of net-radiation are not available and consequently it is challenging to develop multi-year estimates of evapotranspiration at scales that can capture land surface heterogeneity and are relevant for policy and decision-making. We developed and evaluated a global net-radiation product at 5 km and 8-day resolution by combining mutually consistent atmosphere and land data from the Moderate Resolution Imaging Spectroradiometer (MODIS on board Terra. Comparison with net-radiation measurements from 154 globally distributed sites (414 site-years from the FLUXNET and Surface Radiation budget network (SURFRAD showed that the net-radiation product agreed well with measurements across seasons and climate types in the extratropics (Wilmott’s index ranged from 0.74 for boreal to 0.63 for Mediterranean sites. Mean absolute deviation between the MODIS and measured net-radiation ranged from 38.0 ± 1.8 W∙m−2 in boreal to 72.0 ± 4.1 W∙m−2 in the tropical climates. The mean bias was small and constituted only 11%, 0.7%, 8.4%, 4.2%, 13.3%, and 5.4% of the mean absolute error in daytime net-radiation in boreal, Mediterranean, temperate-continental, temperate, semi-arid, and tropical climate, respectively. To assess the accuracy of the broader spatiotemporal patterns, we upscaled error-quantified MODIS net-radiation and compared it with the net-radiation estimates from the coarse spatial (1° × 1° but high temporal resolution gridded net-radiation product from the Clouds and Earth’s Radiant Energy System (CERES. Our estimates agreed closely with the net-radiation estimates from the CERES. Difference between the two was less than 10 W·m−2 in 94% of the total land area. MODIS net-radiation product will be a valuable resource for the

  15. Numbers game : using aluminum helps Global Heat Transfer develop new frac radiators

    Marsters, S.

    2009-11-15

    Aluminum is thought to be a beneficial new option for the construction of frac radiators. This article discussed how aluminum has been used to help Global Heat Transfer Ltd. (GHT) develop new frac radiators. The company developed the Jumbotron, an all-aluminum frac radiator that achieved 3,000 horsepower, but with less weight than a typical 2,250 horsepower package. The article provided information on Jumbotron, including how it was conceptualized, its features, applications, and other details. Background information on GHT was also presented. GHT focuses on the oil and gas and mining sectors and has over 500 employees worldwide in 15 locations. The aluminum parts for the Jumbotron frac radiator are produced at one of GHT's China facilities and brought to Canada for final assembly. 1 fig.

  16. Effective aerosol optical depth from pyranometer measurements of surface solar radiation (global radiation at Thessaloniki, Greece

    A. V. Lindfors

    2013-04-01

    Full Text Available Pyranometer measurements of the solar surface radiation (SSR are available at many locations worldwide, often as long time series covering several decades into the past. These data constitute a potential source of information on the atmospheric aerosol load. Here, we present a method for estimating the aerosol optical depth (AOD using pyranometer measurements of the SSR together with total water vapor column information. The method, which is based on radiative transfer simulations, was developed and tested using recent data from Thessaloniki, Greece. The effective AOD calculated using this method was found to agree well with co-located AERONET measurements, exhibiting a correlation coefficient of 0.9 with 2/3 of the data found within ±20% or ±0.05 of the AERONET AOD. This is similar to the performance of current satellite aerosol methods. Differences in the AOD as compared to AERONET can be explained by variations in the aerosol properties of the atmosphere that are not accounted for in the idealized settings used in the radiative transfer simulations, such as variations in the single scattering albedo and Ångström exponent. Furthermore, the method is sensitive to calibration offsets between the radiative transfer simulations and the pyranometer SSR. The method provides an opportunity of extending our knowledge of the atmospheric aerosol load to locations and times not covered by dedicated aerosol measurements.

  17. Estimating the global prevalence of inadequate zinc intake from national food balance sheets: effects of methodological assumptions.

    K Ryan Wessells

    Full Text Available The prevalence of inadequate zinc intake in a population can be estimated by comparing the zinc content of the food supply with the population's theoretical requirement for zinc. However, assumptions regarding the nutrient composition of foods, zinc requirements, and zinc absorption may affect prevalence estimates. These analyses were conducted to: (1 evaluate the effect of varying methodological assumptions on country-specific estimates of the prevalence of dietary zinc inadequacy and (2 generate a model considered to provide the best estimates.National food balance data were obtained from the Food and Agriculture Organization of the United Nations. Zinc and phytate contents of these foods were estimated from three nutrient composition databases. Zinc absorption was predicted using a mathematical model (Miller equation. Theoretical mean daily per capita physiological and dietary requirements for zinc were calculated using recommendations from the Food and Nutrition Board of the Institute of Medicine and the International Zinc Nutrition Consultative Group. The estimated global prevalence of inadequate zinc intake varied between 12-66%, depending on which methodological assumptions were applied. However, country-specific rank order of the estimated prevalence of inadequate intake was conserved across all models (r = 0.57-0.99, P<0.01. A "best-estimate" model, comprised of zinc and phytate data from a composite nutrient database and IZiNCG physiological requirements for absorbed zinc, estimated the global prevalence of inadequate zinc intake to be 17.3%.Given the multiple sources of uncertainty in this method, caution must be taken in the interpretation of the estimated prevalence figures. However, the results of all models indicate that inadequate zinc intake may be fairly common globally. Inferences regarding the relative likelihood of zinc deficiency as a public health problem in different countries can be drawn based on the country

  18. New horizontal global solar radiation estimation models for Turkey based on robust coplot supported genetic programming technique

    Demirhan, Haydar; Kayhan Atilgan, Yasemin

    2015-01-01

    Highlights: • Precise horizontal global solar radiation estimation models are proposed for Turkey. • Genetic programming technique is used to construct the models. • Robust coplot analysis is applied to reduce the impact of outlier observations. • Better estimation and prediction properties are observed for the models. - Abstract: Renewable energy sources have been attracting more and more attention of researchers due to the diminishing and harmful nature of fossil energy sources. Because of the importance of solar energy as a renewable energy source, an accurate determination of significant covariates and their relationships with the amount of global solar radiation reaching the Earth is a critical research problem. There are numerous meteorological and terrestrial covariates that can be used in the analysis of horizontal global solar radiation. Some of these covariates are highly correlated with each other. It is possible to find a large variety of linear or non-linear models to explain the amount of horizontal global solar radiation. However, models that explain the amount of global solar radiation with the smallest set of covariates should be obtained. In this study, use of the robust coplot technique to reduce the number of covariates before going forward with advanced modelling techniques is considered. After reducing the dimensionality of model space, yearly and monthly mean daily horizontal global solar radiation estimation models for Turkey are built by using the genetic programming technique. It is observed that application of robust coplot analysis is helpful for building precise models that explain the amount of global solar radiation with the minimum number of covariates without suffering from outlier observations and the multicollinearity problem. Consequently, over a dataset of Turkey, precise yearly and monthly mean daily global solar radiation estimation models are introduced using the model spaces obtained by robust coplot technique and

  19. Influence of Ice Particle Surface Roughening on the Global Cloud Radiative Effect

    Yi, Bingqi; Yang, Ping; Baum, Bryan A.; LEcuyer, Tristan; Oreopoulos, Lazaros; Mlawer, Eli J.; Heymsfield, Andrew J.; Liou, Kuo-Nan

    2013-01-01

    Ice clouds influence the climate system by changing the radiation budget and large-scale circulation. Therefore, climate models need to have an accurate representation of ice clouds and their radiative effects. In this paper, new broadband parameterizations for ice cloud bulk scattering properties are developed for severely roughened ice particles. The parameterizations are based on a general habit mixture that includes nine habits (droxtals, hollow/solid columns, plates, solid/hollow bullet rosettes, aggregate of solid columns, and small/large aggregates of plates). The scattering properties for these individual habits incorporate recent advances in light-scattering computations. The influence of ice particle surface roughness on the ice cloud radiative effect is determined through simulations with the Fu-Liou and the GCM version of the Rapid Radiative Transfer Model (RRTMG) codes and the National Center for Atmospheric Research Community Atmosphere Model (CAM, version 5.1). The differences in shortwave (SW) and longwave (LW) radiative effect at both the top of the atmosphere and the surface are determined for smooth and severely roughened ice particles. While the influence of particle roughening on the single-scattering properties is negligible in the LW, the results indicate that ice crystal roughness can change the SW forcing locally by more than 10 W m(exp -2) over a range of effective diameters. The global-averaged SW cloud radiative effect due to ice particle surface roughness is estimated to be roughly 1-2 W m(exp -2). The CAM results indicate that ice particle roughening can result in a large regional SW radiative effect and a small but nonnegligible increase in the global LW cloud radiative effect.

  20. A new simple parameterization of daily clear-sky global solar radiation including horizon effects

    Lopez, Gabriel; Javier Batlles, F.; Tovar-Pescador, Joaquin

    2007-01-01

    Estimation of clear-sky global solar radiation is usually an important previous stage for calculating global solar radiation under all sky conditions. This is, for instance, a common procedure to derive incoming solar radiation from remote sensing or by using digital elevation models. In this work, we present a new model to calculate daily values of clear-sky global solar irradiation. The main goal is the simple parameterization in terms of atmospheric temperature and relative humidity, Angstroem's turbidity coefficient, ground albedo and site elevation, including a factor to take into account horizon obstructions. This allows us to obtain estimates even though a free horizon is not present as is the case of mountainous locations. Comparisons of calculated daily values with measured data show that this model is able to provide a good level of accurate estimates using either daily or mean monthly values of the input parameters. This new model has also been shown to improve daily estimates against those obtained using the clear-sky model from the European Solar Radiation Atlas and other accurate parameterized daily irradiation models. The introduction of Angstroem's turbidity coefficient and ground albedo should allow us to use the increasing worldwide aerosol information available and to consider those sites affected by snow covers in an easy and fast way. In addition, the proposed model is intended to be a useful tool to select clear-sky conditions

  1. Effects of aerosol/cloud interactions on the global radiation budget

    Chuang, C.C.; Penner, J.E.

    1994-01-01

    Aerosols may modify the microphysics of clouds by acting as cloud condensation nuclei (CCN), thereby enhancing the cloud reflectivity. Aerosols may also alter precipitation development by affecting the mean droplet size, thereby influencing cloud lifetimes and modifying the hydrological cycle. Clouds have a major effect on climate, but aerosol/cloud interactions have not been accounted for in past climate model simulations. However, the worldwide steady rise of global pollutants and emissions makes it imperative to investigate how atmospheric aerosols affect clouds and the global radiation budget. In this paper, the authors examine the relationship between aerosol and cloud drop size distributions by using a detailed micro-physical model. They parameterize the cloud nucleation process in terms of local aerosol characteristics and updraft velocity for use in a coupled climate/chemistry model to predict the magnitude of aerosol cloud forcing. Their simulations indicate that aerosol/cloud interactions may result in important increases in reflected solar radiation, which would mask locally the radiative forcing from increased greenhouse gases. This work is aimed at improving the assessment of the effects of anthropogenic aerosols on cloud optical properties and the global radiation budget

  2. The Impact of Desert Dust Aerosol Radiative Forcing on Global and West African Precipitation

    Jordan, A.; Zaitchik, B. F.; Gnanadesikan, A.; Dezfuli, A. K.

    2015-12-01

    Desert dust aerosols exert a radiative forcing on the atmosphere, influencing atmospheric temperature structure and modifying radiative fluxes at the top of the atmosphere (TOA) and surface. As dust aerosols perturb radiative fluxes, the atmosphere responds by altering both energy and moisture dynamics, with potentially significant impacts on regional and global precipitation. Global Climate Model (GCM) experiments designed to characterize these processes have yielded a wide range of results, owing to both the complex nature of the system and diverse differences across models. Most model results show a general decrease in global precipitation, but regional results vary. Here, we compare simulations from GFDL's CM2Mc GCM with multiple other model experiments from the literature in order to investigate mechanisms of radiative impact and reasons for GCM differences on a global and regional scale. We focus on West Africa, a region of high interannual rainfall variability that is a source of dust and that neighbors major Sahara Desert dust sources. As such, changes in West African climate due to radiative forcing of desert dust aerosol have serious implications for desertification feedbacks. Our CM2Mc results show net cooling of the planet at TOA and surface, net warming of the atmosphere, and significant increases in precipitation over West Africa during the summer rainy season. These results differ from some previous GCM studies, prompting comparative analysis of desert dust parameters across models. This presentation will offer quantitative analysis of differences in dust aerosol parameters, aerosol optical properties, and overall particle burden across GCMs, and will characterize the contribution of model differences to the uncertainty of forcing and climate response affecting West Africa.

  3. Shortwave and longwave radiative contributions to global warming under increasing CO2

    Donohoe, Aaron; Armour, Kyle C.; Pendergrass, Angeline G.; Battisti, David S.

    2014-01-01

    In response to increasing concentrations of atmospheric CO2, high-end general circulation models (GCMs) simulate an accumulation of energy at the top of the atmosphere not through a reduction in outgoing longwave radiation (OLR)—as one might expect from greenhouse gas forcing—but through an enhancement of net absorbed solar radiation (ASR). A simple linear radiative feedback framework is used to explain this counterintuitive behavior. It is found that the timescale over which OLR returns to its initial value after a CO2 perturbation depends sensitively on the magnitude of shortwave (SW) feedbacks. If SW feedbacks are sufficiently positive, OLR recovers within merely several decades, and any subsequent global energy accumulation is because of enhanced ASR only. In the GCM mean, this OLR recovery timescale is only 20 y because of robust SW water vapor and surface albedo feedbacks. However, a large spread in the net SW feedback across models (because of clouds) produces a range of OLR responses; in those few models with a weak SW feedback, OLR takes centuries to recover, and energy accumulation is dominated by reduced OLR. Observational constraints of radiative feedbacks—from satellite radiation and surface temperature data—suggest an OLR recovery timescale of decades or less, consistent with the majority of GCMs. Altogether, these results suggest that, although greenhouse gas forcing predominantly acts to reduce OLR, the resulting global warming is likely caused by enhanced ASR. PMID:25385628

  4. Shortwave and longwave radiative contributions to global warming under increasing CO2.

    Donohoe, Aaron; Armour, Kyle C; Pendergrass, Angeline G; Battisti, David S

    2014-11-25

    In response to increasing concentrations of atmospheric CO2, high-end general circulation models (GCMs) simulate an accumulation of energy at the top of the atmosphere not through a reduction in outgoing longwave radiation (OLR)—as one might expect from greenhouse gas forcing—but through an enhancement of net absorbed solar radiation (ASR). A simple linear radiative feedback framework is used to explain this counterintuitive behavior. It is found that the timescale over which OLR returns to its initial value after a CO2 perturbation depends sensitively on the magnitude of shortwave (SW) feedbacks. If SW feedbacks are sufficiently positive, OLR recovers within merely several decades, and any subsequent global energy accumulation is because of enhanced ASR only. In the GCM mean, this OLR recovery timescale is only 20 y because of robust SW water vapor and surface albedo feedbacks. However, a large spread in the net SW feedback across models (because of clouds) produces a range of OLR responses; in those few models with a weak SW feedback, OLR takes centuries to recover, and energy accumulation is dominated by reduced OLR. Observational constraints of radiative feedbacks—from satellite radiation and surface temperature data—suggest an OLR recovery timescale of decades or less, consistent with the majority of GCMs. Altogether, these results suggest that, although greenhouse gas forcing predominantly acts to reduce OLR, the resulting global warming is likely caused by enhanced ASR.

  5. Defining a Leader Role curriculum for radiation oncology: A global Delphi consensus study.

    Turner, Sandra; Seel, Matthew; Trotter, Theresa; Giuliani, Meredith; Benstead, Kim; Eriksen, Jesper G; Poortmans, Philip; Verfaillie, Christine; Westerveld, Henrike; Cross, Shamira; Chan, Ming-Ka; Shaw, Timothy

    2017-05-01

    The need for radiation oncologists and other radiation oncology (RO) professionals to lead quality improvement activities and contribute to shaping the future of our specialty is self-evident. Leadership knowledge, skills and behaviours, like other competencies, can be learned (Blumenthal et al., 2012). The objective of this study was to define a globally applicable competency set specific to radiation oncology for the CanMEDS Leader Role (Frank et al., 2015). A modified Delphi consensus process delivering two rounds of on-line surveys was used. Participants included trainees, radiation/clinical oncologists and other RO team members (radiation therapists, physicists, and nurses), professional educators and patients. 72 of 95 (76%) invitees from nine countries completed the Round 1 (R1) survey. Of the 72 respondents to RI, 70 completed Round 2 (R2) (97%). In R1, 35 items were deemed for 'inclusion' and 21 for 'exclusion', leaving 41 'undetermined'. After review of items, informed by participant comments, 14 competencies from the 'inclusion' group went into the final curriculum; 12 from the 'undetermined' group went to R2. In R2, 6 items reached consensus for inclusion. This process resulted in 20 RO Leader Role competencies with apparent global applicability. This is the first step towards developing learning, teaching and assessment tools for this important area of training. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Elucidation of the fluctuation history of cosmic radiation and global environmental using AMS

    Horiuchi, Kazuho

    2008-01-01

    Recently, accuracy of AMS has further been raised in trace amounts of sample. Besides application of 14 C to the age estimation, it has been able to restore in detail the past fluctuation of cosmic radiation strength using the other radioactive isotopes ( 10 Be, 36 Cl etc) in environmental samples and to elucidate the correlation of this with the fluctuation of climate and environment. In this report, the attempts to elucidate the fluctuation history of cosmic radiation and global environment with ice cores using AMS are presented. (M.H.)

  7. Basic principles of the WHO/UNEP global environmental radiation network

    1988-01-01

    After the accident at Chernobyl, attempts were made to improve radiation monitoring capabilities and the exchange of information at both national and international levels. As part of these efforts it is proposed to establish a Global Environmental Radiation Monitoring Network (GERMON). This report contains an overview of existing national and international programmes, and makes suggestions about the structure and operational requirements of GERMON. Annexes present the existing WHO environmental radioactivity monitoring network; give the measured CS-137 activities in milk samples in France, Sweden, Canada and the USA from 1974 to 1985; and reproduce the text of the Convention on Early Notification of a Nuclear Accident

  8. Radiation chemistry of water at low dose rates with emphasis on the energy balance

    Fletcher, J.W.

    1982-09-01

    There has been considerable interest in absorbed dose water calorimetry. In order to accurately relate the temperature change to the absorbed dose, the energy balance of the overall chemistry of the system must be known. The radiolytic products and their yields are affected by dose rate, dose and added solutes. The yields of the radiolytic products have been calculated using a computer program developed at Atomic Energy of Canada. The chemical energy balance was determined as a function of dose for various dose rates and initial concentrations of hydrogen (H 2 ), oxygen (O 2 ), and hydrogen peroxide (H 2 O 2 ). In solutions containing H 2 O 2 or O 2 and H 2 the chemical reactions were exothermic; in other cases they were endothermic. Approach to equilibrium and equilbrium conditions are discussed

  9. Greenhouse gases, radiative forcing, global warming potential and waste management – an introduction

    Scheutz, Charlotte; Kjeldsen, Peter; Gentil, Emmanuel

    2009-01-01

    forcing (RF) and global warming potential (GWP). This paper provides a general introduction of the factors that define a GHG and explains the scientific background for estimating RF and GWP, thereby exposing the lay reader to a brief overview of the methods for calculating the effects of GHGs on climate......Management of post-consumer solid waste contributes to emission of greenhouse gases (GHGs) representing about 3% of global anthropogenic GHG emissions. Most GHG reporting initiatives around the world utilize two metrics proposed by the Intergovernmental Panel on Climate Change (IPCC): radiative...

  10. The International Atomic Energy Agency's activities in radiation medicine and cancer: promoting global health through diplomacy.

    Deatsch-Kratochvil, Amanda N; Pascual, Thomas Neil; Kesner, Adam; Rosenblatt, Eduardo; Chhem, Rethy K

    2013-02-01

    Global health has been an issue of seemingly low political importance in comparison with issues that have direct bearing on countries' national security. Recently, health has experienced a "political revolution" or a rise in political importance. Today, we face substantial global health challenges, from the spread of infectious disease, gaps in basic maternal and child health care, to the globalization of cancer. A recent estimate states that the "overall lifetime risk of developing cancer (both sexes) is expected to rise from more than one in three to one in two by 2015." These issues pose significant threats to international health security. To successfully combat these grave challenges, the international community must embrace and engage in global health diplomacy, defined by scholars Thomas Novotny and Vicanne Adams as a political activity aimed at improving global health, while at the same time maintaining and strengthening international relations. The IAEA (International Atomic Energy Agency) is an international organization with a unique mandate to "accelerate and enlarge the contribution of atomic energy to peace, health, and prosperity throughout the world." This article discusses global health diplomacy, reviews the IAEA's program activities in human health by focusing on radiation medicine and cancer, and the peaceful applications of atomic energy within the context of global health diplomacy. Copyright © 2013 Canadian Association of Radiologists. Published by Elsevier Inc. All rights reserved.

  11. Experiments on the Scaling of Ionization Balance vs. Electron and Radiation Temperature in Non-LTE Gold Plasmas

    Heeter, R.F.; Hansen, S.B.; Beiersdorfer, P.; Foord, M.E.; Fournier, K.B.; Froula, D.H.; Mackinnon, A.J.; May, M.J.; Schneider, M.B.; Young, B.K.F.

    2004-01-01

    Understanding and predicting the behavior of high-Z non-LTE plasmas is important for developing indirect-drive inertial confinement fusion. Extending earlier work from the Nova laser, we present results from experiments using the Omega laser to study the ionization balance of gold as a function of electron and radiation temperature. In these experiments, gold samples embedded in Be disks expand under direct laser heating to ne ≅ 1021cm-3, with Te varying from 0.8 to 2.5 keV. An additional finite radiation field with effective temperature Tr up to 150 eV is provided by placing the gold Be disks inside truncated 1.2 mm diameter tungsten-coated cylindrical hohlraums with full laser entrance holes. Densities are measured by imaging of plasma expansion. Electron temperatures are diagnosed with either 2ω or 4ω Thomson scattering, and also K-shell spectroscopy of KCl tracers co-mixed with the gold. Hohlraum flux and effective radiation temperature are measured using an absolutely-calibrated multichannel filtered diode array. Spectroscopic measurements of the M-shell gold emission in the 2.9-4 keV spectral range provide ionization balance and charge state distribution information. The spectra show strong variation with Te, strong variation with the applied Tr, at Te below 1.6 keV, and relatively little variation with Tr at higher Te (upwards of 2 keV). We summarize our most recent spectral analyses and discuss emerging and outstanding issues

  12. Ecosystem carbon and radiative fluxes: a global synthesis based on the FLUXNET network.

    Cescatti, A.

    2009-04-01

    Solar radiation is the most important environmental factor driving the temporal and spatial variability of the gross primary productivity (GPP) in terrestrial ecosystems. At the ecosystem scale, the light use efficiency (LUE) depends not only on radiation quantity but also on radiation "quality" both in terms of spectral composition and angular distribution. The day-to-day variations in LUE are largely determined by changes in the ratio of diffuse to total radiation. The relative importance of the concurrent variation in total incoming radiation and in LUE is essential to estimate the sign and the magnitude of the GPP sensitivity to radiation. Despite the scientific relevance of this issue, a global assessment on the sensitivity of GPP to the variations of Phar is still missing. Such an analysis is needed to improve our understanding of the current and future impacts of aerosols and cloud cover on the spatio-temporal variability of GPP. The current availability of ecosystem carbon fluxes, together with separate measurements of incoming direct and diffuse Phar at a large number of flux sites, offers the unique opportunity to extend the previous investigation, both in terms of ecosystem, spatial and climate coverage, and to address questions about the internal (e.g. leaf area index, canopy structure) and external (e.g. cloudiness, covarying meteorology) factors affecting the ecosystem sensitivity to radiation geometry. For this purpose half-hourly measurements of carbon fluxes and radiation have been analyzed at about 220 flux sites for a total of about 660 site-years. This analysis demonstrates that the sensitivity of GPP to incoming radiation varies across the different plant functional types and is correlated with the leaf area index and the local climatology. In particular, the sensitivity of GPP to changes in incoming diffuse light maximizes for the broadleaved forests of the Northern Hemisphere.

  13. Effects of UVB radiation on net community production in the upper global ocean

    Garcia-Corral, Lara S.

    2016-08-31

    Aim Erosion of the stratospheric ozone layer together with oligotrophication of the subtropical ocean is leading to enhanced exposure to ultraviolet B (UVB) radiation in ocean surface waters. The impact of increased exposure to UVB on planktonic primary producers and heterotrophs is uncertain. Here we test the null hypothesis that net community production (NCP) of plankton communities in surface waters of the tropical and subtropical ocean is not affected by ambient UVB radiation and extend this test to the global ocean, including the polar oceans and the Mediterranean Sea using previous results. Location We conducted experiments with 131 surface communities sampled during a circumnavigation cruise along the tropical and subtropical ocean and combined these results with 89 previous reports encompassing the Atlantic, Pacific, Arctic and Southern Oceans and the Mediterranean Sea. Methods The use of quartz (transparent to UVB radiation) and borosilicate glass materials (opaque to most UVB) for incubations allowed us to compare NCP between communities where UVB is excluded and those receiving natural UVB radiation. Results We found that NCP varies when exposed to natural UVB radiation compared to those where UVB was removed. NCP of autotrophic communities tended to decrease under natural UVB radiation, whereas the NCP of heterotrophic communities tended to increase. However, these variations showed the opposite trend under higher levels of UVB radiation. Main conclusions Our results suggest that earlier estimates of NCP for surface communities, which were hitherto derived using materials blocking UVB radiation were biased, with the direction and magnitude of this bias depending on the metabolic status of the communities and the underwater penetration of UVB radiation.

  14. Balance of longwave radiation employing the rate of solar radiation for Santa Maria, Rio Grande do Sul, Brazil1

    Evandro Zanini Righi

    Full Text Available New coefficients were determined for the weighting term for cloudiness in the Brunt-Penman equation using the rate of solar radiation (RK in place of the rate of sunshine duration (n/N. The coefficients in the Brutsaert method proposed for daytime in southern Brazil were also tested and adjusted, and the method was selected which gave the more accurate daily results in relation to the original Brunt-Penman equation, for Santa Maria in the state of Rio Grande do Sul, Brazil (RS. Meteorological data covering 2,472 days obtained from the automatic and conventional weather stations in Santa Maria were used. The coefficients were adjusted by linear and nonlinear regression methods depending on the model, using 2/3 of the data. The adjusted equations were tested with the remaining 1/3 of the data. The Brunt-Penman equation modified by the term for cloudiness weighted both for solar radiation incident on the surface with no cloudiness (RK,R and for solar radiation incident at the top of the atmosphere (RK,K, were those that resulted in the best statistical indices relative to the original Brunt-Penman equation. In those equations the boundary conditions, 0.3 ≥ RK,R ≥ 1 or RK,K ≤ 0.22, were imposed. Although having similar statistical indices, a sensitivity analysis showed that the Brutsaert equation and other weightings for cloudiness resulted in larger deviations when compared to the original Brunt-Penman equation, in addition to having greater complexity for practical application.

  15. Insights into the diurnal cycle of global Earth outgoing radiation using a numerical weather prediction model

    Gristey, Jake J.; Chiu, J. Christine; Gurney, Robert J.; Morcrette, Cyril J.; Hill, Peter G.; Russell, Jacqueline E.; Brindley, Helen E.

    2018-04-01

    A globally complete, high temporal resolution and multiple-variable approach is employed to analyse the diurnal cycle of Earth's outgoing energy flows. This is made possible via the use of Met Office model output for September 2010 that is assessed alongside regional satellite observations throughout. Principal component analysis applied to the long-wave component of modelled outgoing radiation reveals dominant diurnal patterns related to land surface heating and convective cloud development, respectively explaining 68.5 and 16.0 % of the variance at the global scale. The total variance explained by these first two patterns is markedly less than previous regional estimates from observations, and this analysis suggests that around half of the difference relates to the lack of global coverage in the observations. The first pattern is strongly and simultaneously coupled to the land surface temperature diurnal variations. The second pattern is strongly coupled to the cloud water content and height diurnal variations, but lags the cloud variations by several hours. We suggest that the mechanism controlling the delay is a moistening of the upper troposphere due to the evaporation of anvil cloud. The short-wave component of modelled outgoing radiation, analysed in terms of albedo, exhibits a very dominant pattern explaining 88.4 % of the variance that is related to the angle of incoming solar radiation, and a second pattern explaining 6.7 % of the variance that is related to compensating effects from convective cloud development and marine stratocumulus cloud dissipation. Similar patterns are found in regional satellite observations, but with slightly different timings due to known model biases. The first pattern is controlled by changes in surface and cloud albedo, and Rayleigh and aerosol scattering. The second pattern is strongly coupled to the diurnal variations in both cloud water content and height in convective regions but only cloud water content in marine

  16. Long-term global distribution of earth's shortwave radiation budget at the top of atmosphere

    N. Hatzianastassiou

    2004-01-01

    Full Text Available The mean monthly shortwave (SW radiation budget at the top of atmosphere (TOA was computed on 2.5° longitude-latitude resolution for the 14-year period from 1984 to 1997, using a radiative transfer model with long-term climatological data from the International Satellite Cloud Climatology Project (ISCCP-D2 supplemented by data from the National Centers for Environmental Prediction – National Center for Atmospheric Research (NCEP-NCAR Global Reanalysis project, and other global data bases such as TIROS Operational Vertical Sounder (TOVS and Global Aerosol Data Set (GADS. The model radiative fluxes at TOA were validated against Earth Radiation Budget Experiment (ERBE S4 scanner satellite data (1985–1989. The model is able to predict the seasonal and geographical variation of SW TOA fluxes. On a mean annual and global basis, the model is in very good agreement with ERBE, overestimating the outgoing SW radiation at TOA (OSR by 0.93 Wm-2 (or by 0.92%, within the ERBE uncertainties. At pixel level, the OSR differences between model and ERBE are mostly within ±10 Wm-2, with ±5 Wm-2 over extended regions, while there exist some geographic areas with differences of up to 40 Wm-2, associated with uncertainties in cloud properties and surface albedo. The 14-year average model results give a planetary albedo equal to 29.6% and a TOA OSR flux of 101.2 Wm-2. A significant linearly decreasing trend in OSR and planetary albedo was found, equal to 2.3 Wm-2 and 0.6% (in absolute values, respectively, over the 14-year period (from January 1984 to December 1997, indicating an increasing solar planetary warming. This planetary SW radiative heating occurs in the tropical and sub-tropical areas (20° S–20° N, with clouds being the most likely cause. The computed global mean OSR anomaly ranges within ±4 Wm-2, with signals from El Niño and La Niña events or Pinatubo eruption, whereas significant negative OSR anomalies, starting from year 1992, are also

  17. Accounting for radiative forcing from albedo change in future global land-use scenarios

    Jones, Andrew D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Calvin, Katherine V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Collins, William D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Edmonds, James A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-08-01

    We demonstrate the effectiveness of a new method for quantifying radiative forcing from land use and land cover change (LULCC) within an integrated assessment model, the Global Change Assessment Model (GCAM). The method relies on geographically differentiated estimates of radiative forcing from albedo change associated with major land cover transitions derived from the Community Earth System Model. We find that conversion of 1 km² of woody vegetation (forest and shrublands) to non-woody vegetation (crops and grassland) yields between 0 and –0.71 nW/m² of globally averaged radiative forcing determined by the vegetation characteristics, snow dynamics, and atmospheric radiation environment characteristic within each of 151 regions we consider globally. Across a set of scenarios designed to span a range of potential future LULCC, we find LULCC forcing ranging from –0.06 to –0.29 W/m² by 2070 depending on assumptions regarding future crop yield growth and whether climate policy favors afforestation or bioenergy crops. Inclusion of this previously uncounted forcing in the policy targets driving future climate mitigation efforts leads to changes in fossil fuel emissions on the order of 1.5 PgC/yr by 2070 for a climate forcing limit of 4.5 Wm–2, corresponding to a 12–67 % change in fossil fuel emissions depending on the scenario. Scenarios with significant afforestation must compensate for albedo-induced warming through additional emissions reductions, and scenarios with significant deforestation need not mitigate as aggressively due to albedo-induced cooling. In all scenarios considered, inclusion of albedo forcing in policy targets increases forest and shrub cover globally.

  18. Numerical weather prediction (NWP) and hybrid ARMA/ANN model to predict global radiation

    Voyant, Cyril; Muselli, Marc; Paoli, Christophe; Nivet, Marie-Laure

    2012-01-01

    We propose in this paper an original technique to predict global radiation using a hybrid ARMA/ANN model and data issued from a numerical weather prediction model (NWP). We particularly look at the multi-layer perceptron (MLP). After optimizing our architecture with NWP and endogenous data previously made stationary and using an innovative pre-input layer selection method, we combined it to an ARMA model from a rule based on the analysis of hourly data series. This model has been used to forecast the hourly global radiation for five places in Mediterranean area. Our technique outperforms classical models for all the places. The nRMSE for our hybrid model MLP/ARMA is 14.9% compared to 26.2% for the naïve persistence predictor. Note that in the standalone ANN case the nRMSE is 18.4%. Finally, in order to discuss the reliability of the forecaster outputs, a complementary study concerning the confidence interval of each prediction is proposed. -- Highlights: ► Time series forecasting with hybrid method based on the use of ALADIN numerical weather model, ANN and ARMA. ► Innovative pre-input layer selection method. ► Combination of optimized MLP and ARMA model obtained from a rule based on the analysis of hourly data series. ► Stationarity process (method and control) for the global radiation time series.

  19. The Role of Cerenkov Radiation in the Pressure Balance of Cool Core Clusters of Galaxies

    Lieu, Richard [Department of Physics, University of Alabama, Huntsville, AL 35899 (United States)

    2017-03-20

    Despite the substantial progress made recently in understanding the role of AGN feedback and associated non-thermal effects, the precise mechanism that prevents the core of some clusters of galaxies from collapsing catastrophically by radiative cooling remains unidentified. In this Letter, we demonstrate that the evolution of a cluster's cooling core, in terms of its density, temperature, and magnetic field strength, inevitably enables the plasma electrons there to quickly become Cerenkov loss dominated, with emission at the radio frequency of ≲350 Hz, and with a rate considerably exceeding free–free continuum and line emission. However, the same does not apply to the plasmas at the cluster's outskirts, which lacks such radiation. Owing to its low frequency, the radiation cannot escape, but because over the relevant scale size of a Cerenkov wavelength the energy of an electron in the gas cannot follow the Boltzmann distribution to the requisite precision to ensure reabsorption always occurs faster than stimulated emission, the emitting gas cools before it reheats. This leaves behind the radiation itself, trapped by the overlying reflective plasma, yet providing enough pressure to maintain quasi-hydrostatic equilibrium. The mass condensation then happens by Rayleigh–Taylor instability, at a rate determined by the outermost radius where Cerenkov radiation can occur. In this way, it is possible to estimate the rate at ≈2 M {sub ⊙} year{sup −1}, consistent with observational inference. Thus, the process appears to provide a natural solution to the longstanding problem of “cooling flow” in clusters; at least it offers another line of defense against cooling and collapse should gas heating by AGN feedback be inadequate in some clusters.

  20. Influence which masses of clouds have on the global solar radiation at Salamanca (Spain)

    Pablo-Davila, F. de; Labajo, J.L.; Tomas-Sanchez, C.

    1991-01-01

    It has been shown the influence which masses of clouds, (and more specifically for each group of cloud types: high, middle and low clauds), has on the global solar radiation recorded at Matacan (Salamanca), within the period 1977-1985. For this purpose, cloud observation were made every three hours; daily records of sunshine and solar radiation were continually taken too. It has also been, both graphically and numerically, the influence of each cloud type for monthly and seasonal periods. Futhermore, different statistical parameters have been presented in order to describe the method developed. Finally, the results have been analysed and evaluated. They have been explaines according to the composition, structure and radiative properties of clouds.(Author)

  1. Verification of Global Radiation Forecasts from the Ensemble Prediction System at DMI

    Lundholm, Sisse Camilla

    To comply with an increasing demand for sustainable energy sources, a solar heating unit is being developed at the Technical University of Denmark. To make optimal use — environmentally and economically —, this heating unit is equipped with an intelligent control system using forecasts of the heat...... consumption of the house and the amount of available solar energy. In order to make the most of this solar heating unit, accurate forecasts of the available solar radiation are esstential. However, because of its sensitivity to local meteorological conditions, the solar radiation received at the surface...... of the Earth can be highly fluctuating and challenging to forecast accurately. To comply with the accuracy requirements to forecasts of both global, direct, and diffuse radiation, the uncertainty of these forecasts is of interest. Forecast uncertainties can become accessible by running an ensemble of forecasts...

  2. Higher plants and UV-B radiation: balancing damage, repair and acclimation

    Jansen, M.A.K.; Gaba, V.; Greenberg, B.M.

    1998-01-01

    Although UV-B is a minor component of sunlight, it has a disproportionately damaging effect on higher plants. Ultraviolet-sensitive targets include DNA, proteins and membranes, and these must be protected for normal growth and development. DNA repair and secondary metabolite accumulation during exposure to UV-B have been characterized in considerable detail, but little is known about the recovery of photosynthesis, induction of free-radical scavenging and morphogenic changes. A future challenge is to elucidate how UV-B-exposed plants balance damage, repair, acclimation and adaptation responses in a photobiologically dynamic environment. (author)

  3. Uncertainties in global radiation time series forecasting using machine learning: The multilayer perceptron case

    Voyant, Cyril; Notton, Gilles; Darras, Christophe; Fouilloy, Alexis; Motte, Fabrice

    2017-01-01

    As global solar radiation forecasting is a very important challenge, several methods are devoted to this goal with different levels of accuracy and confidence. In this study we propose to better understand how the uncertainty is propagated in the context of global radiation time series forecasting using machine learning. Indeed we propose to decompose the error considering four kinds of uncertainties: the error due to the measurement, the variability of time series, the machine learning uncertainty and the error related to the horizon. All these components of the error allow to determinate a global uncertainty generating prediction bands related to the prediction efficiency. We also have defined a reliability index which could be very interesting for the grid manager in order to estimate the validity of predictions. We have experimented this method on a multilayer perceptron which is a popular machine learning technique. We have shown that the global error and its components are essential to quantify in order to estimate the reliability of the model outputs. The described method has been successfully applied to four meteorological stations in Mediterranean area. - Highlights: • Solar irradiation predictions require confidence bands. • There are a lot of kinds of uncertainties to take into account in order to propose prediction bands. • the ranking of different kinds of uncertainties is essential to propose an operational tool for the grid managers.

  4. Global water balances reconstructed by multi-model offline simulations of land surface models under GSWP3 (Invited)

    Oki, T.; KIM, H.; Ferguson, C. R.; Dirmeyer, P.; Seneviratne, S. I.

    2013-12-01

    . Forcings for this period are produced from a select number of GCM-representative concentration pathways (RCPs) pairings. GSWP3 is specifically directed towards addressing the following key science questions: 1. How have interactions between eco-hydrological processes changed in the long term within a changing climate? 2. What is /will be the state of the water, energy, and carbon balances over land in the 20th and 21st centuries and what are the implications of the anticipated changes for human society in terms of freshwater resources, food productivity, and biodiversity? 3. How do the state-of-the-art land surface modeling systems perform and how can they be improved? In this presentation, we present preliminary results relevant to science question two, including: revised best-estimate global hydrological cycles for the retrospective period, inter-comparisons of modeled terrestrial water storage in large river basins and satellite remote-sensing estimates from the Gravity Recovery and Climate Experiment (GRACE), and the impacts of climate and anthropogenic changes during the 20th century on the long-term trend of water availability and scarcity.

  5. Decadal changes in shortwave irradiance at the surface in the period from 1960 to 2000 estimated from Global Energy Balance Archive Data

    Gilgen, H.; Roesch, A.; Wild, M.; Ohmura, A.

    2009-05-01

    Decadal changes in shortwave irradiance at the Earth's surface are estimated for the period from approximately 1960 through to 2000 from pyranometer records stored in the Global Energy Balance Archive. For this observational period, estimates could be calculated for a total of 140 cells of the International Satellite Cloud Climatology Project grid (an equal area 2.5° × 2.5° grid at the equator) using regression models allowing for station effects. In large regions worldwide, shortwave irradiance decreases in the first half of the observational period, recovers from the decrease in the 1980s, and thereafter increases, in line with previous reports. Years of trend reversals are determined for the grid cells which are best described with a second-order polynomial model. This reversal of the trend is observed in the majority of the grid cells in the interior of Europe and in Japan. In China, shortwave irradiance recovers during the 1990s in the majority of the grid cells in the southeast and northeast from the decrease observed in the period from 1960 through to 1990. A reversal of the trend in the 1980s or early 1990s is also observed for two grid cells in North America, and for the grid cells containing the Kuala Lumpur (Malaysia), Singapore, Casablanca (Morocco), Valparaiso (Chile) sites, and, noticeably, the remote South Pole and American Samoa sites. Negative trends persist, i.e., shortwave radiation decreases, for the observational period 1960 through to 2000 at the European coasts, in central and northwest China, and for three grid cells in India and two in Africa.

  6. Estimating the daily global solar radiation spatial distribution from diurnal temperature ranges over the Tibetan Plateau in China

    Pan, Tao; Wu, Shaohong; Dai, Erfu; Liu, Yujie

    2013-01-01

    Highlights: ► Bristow–Campbell model was calibrated and validated over the Tibetan Plateau. ► Develop a simple method to rasterise the daily global solar radiation and get gridded information. ► The daily global solar radiation spatial distribution over the Tibetan Plateau was estimated. - Abstract: Daily global solar radiation is fundamental to most ecological and biophysical processes because it plays a key role in the local and global energy budget. However, gridded information about the spatial distribution of solar radiation is limited. This study aims to parameterise the Bristow–Campbell model for the daily global solar radiation estimation in the Tibetan Plateau and propose a method to rasterise the daily global solar radiation. Observed daily solar radiation and diurnal temperature data from eleven stations over the Tibetan Plateau during 1971–2010 were used to calibrate and validate the Bristow–Campbell radiation model. The extra-terrestrial radiation and clear sky atmospheric transmittance were calculated on a Geographic Information System (GIS) platform. Results show that the Bristow–Campbell model performs well after adjusting the parameters, the average Pearson’s correlation coefficients (r), Nash–Sutcliffe equation (NSE), ratio of the root mean square error to the standard deviation of measured data (RSR), and root mean-square error (RMSE) of 11 stations are 0.85, 2.81 MJ m −2 day −1 , 0.3 and 0.77 respectively. Gridded maximum and minimum average temperature data were obtained using Parameter-elevation Regressions on Independent Slopes Model (PRISM) and validated by the Chinese Ecosystem Research Network (CERN) stations’ data. The spatial daily global solar radiation distribution pattern was estimated and analysed by combining the solar radiation model (Bristow–Campbell model) and meteorological interpolation model (PRISM). Based on the overall results, it can be concluded that a calibrated Bristow–Campbell performs well

  7. A simple formula for estimating global solar radiation in central arid deserts of Iran

    Sabziparvar, Ali A.

    2008-01-01

    Over the last two decades, using simple radiation models has been an interesting task to estimate daily solar radiation in arid and semi-arid deserts such as those in Iran, where the number of solar observation sites is poor. In Iran, most of the models used so far, have been validated for a few specific locations based on short-term solar observations. In this work, three different radiation models (Sabbagh, Paltridge, Daneshyar) have been revised to predict the climatology of monthly average daily solar radiation on horizontal surfaces in various cities in central arid deserts of Iran. The modifications are made by the inclusion of altitude, monthly total number of dusty days and seasonal variation of Sun-Earth distance. A new height-dependent formula is proposed based on MBE, MABE, MPE and RMSE statistical analysis. It is shown that the revised Sabbagh method can be a good estimator for the prediction of global solar radiation in arid and semi-arid deserts with an average error of less than 2%, that performs a more accurate prediction than those in the previous studies. The required data for the suggested method are usually available in most meteorological sites. For the locations, where some of the input data are not reported, an alternative approach is presented. (author)

  8. Global solar energy radiation in relation with electricity supply in Romania

    Zoran, Maria

    2001-01-01

    Solar energy is one of the most viable source of renewable energy being both clean and nonpolluting. Spiraling energy use and other human activities have led to measurable effects upon the global environment and climatic changes. There is increasing international concern particularly in the areas of global warming owing to the increase of carbon dioxide (CO 2 ) in the atmosphere and of other greenhouse gases as sulfur dioxide (SO 2 ), oxides of nitrogen (NOx), hydrogen sulfide H 2 S, diethyl sulfide (DMS), chlorofluorocarbons (CFCs), methane CH 4 , as well in the effect of depletion of ozone (O 3 ) layer in the stratosphere. Climatological and global solar radiation analysis for some Romanian zones with great solar energy potential are presented. Remote sensing data provided by satellites are used for radiative fluxes monitoring and solar energy mapping as well as for solar energy use assessment. The realistic technical potential for solar energy applications in Romania is substantial, over 40000 TJyear -1 . As average energy global solar radiation in horizontal plane lies between 1100 and 1300 kWhm -2 year -1 , solar energy using for electrical power supply being a reliable alternative. More than one half of Romania's area has a range of insolation period between 1200 and 1500 hours year -1 , at an overall average daily irradiation of 1000 - 1200 kWh m -2 . The most favorable area in Romania is the North - Western part of Black Sea coast with an insolation period above 2300 hours year -1 . A small part 140 TJyear -1 are used profitably and almost 10% of the installed 10 6 m 2 of collector area, is still in operation. (author)

  9. Comparison of fluoro and cine coronary angiography: balancing acceptable outcomes with a reduction in radiation dose.

    Olcay, Ayhan; Guler, Ekrem; Karaca, Ibrahim Oguz; Omaygenc, Mehmet Onur; Kizilirmak, Filiz; Olgun, Erkam; Yenipinar, Esra; Cakmak, Huseyin Altug; Duman, Dursun

    2015-04-01

    Use of last fluoro hold (LFH) mode in fluoroscopy, which enables the last live image to be saved and displayed, could reduce radiation during percutaneous coronary intervention when compared with cine mode. No previous study compared coronary angiography radiation doses and image quality between LFH and conventional cine mode techniques. We compared cumulative dose-area product (DAP), cumulative air kerma, fluoroscopy time, contrast use, interobserver variability of visual assessment between LFH angiography, and conventional cine angiography techniques. Forty-six patients were prospectively enrolled into the LFH group and 82 patients into the cine angiography group according to operator decision. Mean cumulative DAP was higher in the cine group vs the LFH group (50058.98 ± 53542.71 mGy•cm² vs 11349.2 ± 8796.46 mGy•cm²; Pcine group vs the LFH group (3.87 ± 5.08 minutes vs 1.66 ± 1.51 minutes; Pcine group vs the LFH group (112.07 ± 43.79 cc vs 88.15 ± 23.84 cc; Pcine and LFH angiography groups (0.66680 ± 0.19309 vs 0.54193 ± 0.31046; P=.20). Radiation doses, contrast use, and fluoroscopy times are lower in fluoroscopic LFH angiography vs cine angiography. Interclass variability of visual stenosis estimation between three operators was not different between cine and LFH groups. Fluoroscopic LFH images conventionally have inferior diagnostic quality when compared with cine coronary angiography, but with new angiographic systems with improved LFH image quality, these images may be adequate for diagnostic coronary angiography.

  10. Global, direct and diffuse solar radiation on horizontal and tilted surfaces in Jeddah, Saudi Arabia

    El-Sebaii, A.A.; Al-Hazmi, F.S.; Al-Ghamdi, A.A.; Yaghmour, S.J.

    2010-01-01

    The measured data of global and diffuse solar radiation on a horizontal surface, the number of bright sunshine hours, mean daily ambient temperature, maximum and minimum ambient temperatures, relative humidity and amount of cloud cover for Jeddah (lat. 21 o 42'37''N, long. 39 o 11'12''E), Saudi Arabia, during the period (1996-2007) are analyzed. The monthly averages of daily values for these meteorological variables have been calculated. The data are then divided into two sets. The sub-data set I (1996-2004) are employed to develop empirical correlations between the monthly average of daily global solar radiation fraction (H/H 0 ) and the various weather parameters. The sub-data set II (2005-2007) are then used to evaluate the derived correlations. Furthermore, the total solar radiation on horizontal surfaces is separated into the beam and diffuses components. Empirical correlations for estimating the diffuse solar radiation incident on horizontal surfaces have been proposed. The total solar radiation incident on a tilted surface facing south H t with different tilt angles is then calculated using both Liu and Jordan isotropic model and Klucher's anisotropic model. It is inferred that the isotropic model is able to estimate H t more accurate than the anisotropic one. At the optimum tilt angle, the maximum value of H t is obtained as ∼36 (MJ/m 2 day) during January. Comparisons with 22 years average data of NASA SSE Model showed that the proposed correlations are able to predict the total annual energy on horizontal and tilted surfaces in Jeddah with a reasonable accuracy. It is also found that at Jeddah, the solar energy devices have to be tilted to face south with a tilt angle equals the latitude of the place in order to achieve the best performance all year round.

  11. Intelligent optimization models based on hard-ridge penalty and RBF for forecasting global solar radiation

    Jiang, He; Dong, Yao; Wang, Jianzhou; Li, Yuqin

    2015-01-01

    Highlights: • CS-hard-ridge-RBF and DE-hard-ridge-RBF are proposed to forecast solar radiation. • Pearson and Apriori algorithm are used to analyze correlations between the data. • Hard-ridge penalty is added to reduce the number of nodes in the hidden layer. • CS algorithm and DE algorithm are used to determine the optimal parameters. • Proposed two models have higher forecasting accuracy than RBF and hard-ridge-RBF. - Abstract: Due to the scarcity of equipment and the high costs of maintenance, far fewer observations of solar radiation are made than observations of temperature, precipitation and other weather factors. Therefore, it is increasingly important to study several relevant meteorological factors to accurately forecast solar radiation. For this research, monthly average global solar radiation and 12 meteorological parameters from 1998 to 2010 at four sites in the United States were collected. Pearson correlation coefficients and Apriori association rules were successfully used to analyze correlations between the data, which provided a basis for these relative parameters as input variables. Two effective and innovative methods were developed to forecast monthly average global solar radiation by converting a RBF neural network into a multiple linear regression problem, adding a hard-ridge penalty to reduce the number of nodes in the hidden layer, and applying intelligent optimization algorithms, such as the cuckoo search algorithm (CS) and differential evolution (DE), to determine the optimal center and scale parameters. The experimental results show that the proposed models produce much more accurate forecasts than other models

  12. Estimating the Global Agricultural Impact of Solar Radiation Management using Volcanic Eruptions as Natural Experiments

    Proctor, J.; Hsiang, S. M.; Burney, J. A.; Burke, M.; Schlenker, W.

    2017-12-01

    Solar radiation management (SRM) is increasingly considered an option for managing global temperatures, yet the economic impacts of ameliorating climatic changes by scattering sunlight back to space remain largely unknown. Though SRM may increase crop yields by reducing heat stress, its impacts from concomitant changes in available sunlight have never been empirically estimated. Here we use the volcanic eruptions that inspired modern SRM proposals as natural experiments to provide the first estimates of how the stratospheric sulfate aerosols (SS) created by the eruptions of El Chichon and Pinatubo altered the quantity and quality of global sunlight, how those changes in sunlight impacted global crop yields, and the total effect that SS may have on yields in an SRM scenario when the climatic and sunlight effects are jointly considered. We find that the sunlight-mediated impact of SS on yields is negative for both C4 (maize) and C3 (soy, rice, wheat) crops. Applying our yield model to a geoengineering scenario using SS-based SRM from 2050-2069, we find that SRM damages due to scattering sunlight are roughly equal in magnitude to SRM benefits from cooling. This suggests that SRM - if deployed using SS similar to those emitted by the volcanic eruptions it seeks to mimic - would attenuate little of the damages from climate change to global agriculture on net. Our approach could be extended to study SRM impacts on other global systems, such as human health or ecosystem function.

  13. Application of a hybrid method for downscaling of the global climate model fields for evaluation of future surface mass balance of mountain glaciers

    Morozova, Polina; Rybak, Oleg; Kaminskaia, Mariia

    2017-04-01

    Mountain glaciers in the Caucasus have been degrading during the last century. During this time period they lost approximately one-third in area and half of their volume. Prediction of their evolution in changing climate is crucial for the local economy because hydrological regime in the territory north to the Main Caucasus Chain is mainly driven by glacier run-off. For future projections of glaciers' surface mass balance (SMB) we apply a hybrid method of downscaling of GCM-generated meteorological fields from the global scale to the characteristic spatial resolution normally used for modeling of a single mountain glacier SMB. A method consists of two stages. On the first, dynamical stage, we use the results of calculations of regional climate model (RCM) HadRM3P for the Black Sea-Caspian region with a spatial resolution of approximately 25 km. Initial and boundary conditions for HadRM3P are provided by an AO GCM INMCM developed in the Institute of Numerical Mathematics (Moscow, Russia). Calculations were carried out for two time slices: the present (reference) climate (1971-2000 years) and climate in the late 21st century (2071-2100 years) according to scenario of greenhouse gas emissions RCP 8.5. On the second stage of downscaling, further regionalization is achieved by projecting of RCM-generated data to the high-resolution (25 m) digital elevation models in a domain enclosing target glaciers (Marukh in the Western Caucasus and Djankuat in the Central Caucasus, both being typical valley glaciers). Elevation gradient of surface air temperature and precipitation were derived from the model data. Further, results were corrected using data of observations. The incoming shortwave radiation is calculated separately, taking into account slopes, aspects and shade effect. In the end of the current century expected air temperature growth in the Central and Western Caucasus is about 5-6 °C (summer), and 2-3 °C (winter). Reduction in annual precipitation is not

  14. Artificial neural network optimisation for monthly average daily global solar radiation prediction

    Alsina, Emanuel Federico; Bortolini, Marco; Gamberi, Mauro; Regattieri, Alberto

    2016-01-01

    Highlights: • Prediction of the monthly average daily global solar radiation over Italy. • Multi-location Artificial Neural Network (ANN) model: 45 locations considered. • Optimal ANN configuration with 7 input climatologic/geographical parameters. • Statistical indicators: MAPE, NRMSE, MPBE. - Abstract: The availability of reliable climatologic data is essential for multiple purposes in a wide set of anthropic activities and operative sectors. Frequently direct measures present spatial and temporal lacks so that predictive approaches become of interest. This paper focuses on the prediction of the Monthly Average Daily Global Solar Radiation (MADGSR) over Italy using Artificial Neural Networks (ANNs). Data from 45 locations compose the multi-location ANN training and testing sets. For each location, 13 input parameters are considered, including the geographical coordinates and the monthly values for the most frequently adopted climatologic parameters. A subset of 17 locations is used for ANN training, while the testing step is against data from the remaining 28 locations. Furthermore, the Automatic Relevance Determination method (ARD) is used to point out the most relevant input for the accurate MADGSR prediction. The ANN best configuration includes 7 parameters, only, i.e. Top of Atmosphere (TOA) radiation, day length, number of rainy days and average rainfall, latitude and altitude. The correlation performances, expressed through statistical indicators as the Mean Absolute Percentage Error (MAPE), range between 1.67% and 4.25%, depending on the number and type of the chosen input, representing a good solution compared to the current standards.

  15. Temperature-based estimation of global solar radiation using soft computing methodologies

    Mohammadi, Kasra; Shamshirband, Shahaboddin; Danesh, Amir Seyed; Abdullah, Mohd Shahidan; Zamani, Mazdak

    2016-07-01

    Precise knowledge of solar radiation is indeed essential in different technological and scientific applications of solar energy. Temperature-based estimation of global solar radiation would be appealing owing to broad availability of measured air temperatures. In this study, the potentials of soft computing techniques are evaluated to estimate daily horizontal global solar radiation (DHGSR) from measured maximum, minimum, and average air temperatures ( T max, T min, and T avg) in an Iranian city. For this purpose, a comparative evaluation between three methodologies of adaptive neuro-fuzzy inference system (ANFIS), radial basis function support vector regression (SVR-rbf), and polynomial basis function support vector regression (SVR-poly) is performed. Five combinations of T max, T min, and T avg are served as inputs to develop ANFIS, SVR-rbf, and SVR-poly models. The attained results show that all ANFIS, SVR-rbf, and SVR-poly models provide favorable accuracy. Based upon all techniques, the higher accuracies are achieved by models (5) using T max- T min and T max as inputs. According to the statistical results, SVR-rbf outperforms SVR-poly and ANFIS. For SVR-rbf (5), the mean absolute bias error, root mean square error, and correlation coefficient are 1.1931 MJ/m2, 2.0716 MJ/m2, and 0.9380, respectively. The survey results approve that SVR-rbf can be used efficiently to estimate DHGSR from air temperatures.

  16. A simple method to compute the change in earth-atmosphere radiative balance due to a stratospheric aerosol layer

    Lenoble, J.; Tanre, D.; Deschamps, P. Y.; Herman, M.

    1982-01-01

    A computer code was developed in terms of a three-layer model for the earth-atmosphere system, using a two-stream approximation for the troposphere and stratosphere. The analysis was limited to variable atmosphere loading by solar radiation over an unperturbed section of the atmosphere. The scattering atmosphere above a Lambertian ground layer was considered in order to derive the planar albedo and the spherical albedo. Attention was given to the influence of the aerosol optical thickness in the stratosphere, the single scattering albedo and asymmetry factor, and the sublayer albedo. Calculations were performed of the zonal albedo and the planetary radiation balance, taking into account a stratospheric aerosol layer containing H2SO4 droplets and volcanic ash. The resulting ground temperature disturbance was computed using a Budyko (1969) climate model. Local decreases in the albedo in the summer were observed in high latitudes, implying a heating effect of the aerosol. An accompanying energy loss of 23-27 W/sq m was projected, which translates to surface temperature decreases of either 1.1 and 0.45 C, respectively, for background and volcanic aerosols.

  17. Radiation balance in a soybean ecosystem in the Amazon Balanço de radiação em ecossistema de soja na Amazônia

    Paulo Jorge de Oliveira Ponte de Souza

    2010-12-01

    Full Text Available The continuous advance of the agricultural border in the Amazon has been worrying the scientific community due to the possible environmental impacts caused by this change in land use. The present work evaluated the behavior of the radiation balance components over the soybean crop (Glycine Max (L. Merryl in an Amazon area of continuous advance of the agricultural border. The radiation components were continuously monitored during the soybean cycle in 2006 and 2007 in an area of 200 ha. The soybean cultivation in the Amazon presented an abrupt change in the radiation balance components, with the consequent reduction in the energy available to the environment due to the increase in the surface reflection. There was a significant contribution of the diffuse radiation component in the soybean interception during cloudy conditions, even under incomplete canopy covering. Moreover, after the canopy closure, a similar interaction between soybean and solar radiation occurs, regardless of the cloud condition.O avanço da fronteira agrícola na Amazônia, da forma como vem sendo realizado, tem deixado a comunidade cada vez mais preocupada ante os possíveis impactos ambientais decorrentes desta mudança no uso da terra, devido à grande importância que a Amazônia representa para o clima global. Neste trabalho avaliaram-se os componentes do balanço de radiação à superfície, ao longo do ciclo da soja (Glycine Max (L. Merryl, em uma área de avanço da fronteira agrícola na Amazônia. Os componentes do balanço de radiação foram monitorados continuamente durante o ciclo da soja, em 2006 e 2007, em uma área de 200 ha de extensão. O monocultivo da soja na Amazônia apresentou uma contínua mudança nos componentes do balanço de radiação, tendo como consequência uma redução na energia disponível para o ambiente devido o aumento na reflexão da superfície. Observou-se uma importante contribuição da radiação solar difusa na intercepta

  18. The effect of sea ice loss on sea salt aerosol concentrations and the radiative balance in the Arctic

    H. Struthers

    2011-04-01

    Full Text Available Understanding Arctic climate change requires knowledge of both the external and the local drivers of Arctic climate as well as local feedbacks within the system. An Arctic feedback mechanism relating changes in sea ice extent to an alteration of the emission of sea salt aerosol and the consequent change in radiative balance is examined. A set of idealized climate model simulations were performed to quantify the radiative effects of changes in sea salt aerosol emissions induced by prescribed changes in sea ice extent. The model was forced using sea ice concentrations consistent with present day conditions and projections of sea ice extent for 2100. Sea salt aerosol emissions increase in response to a decrease in sea ice, the model results showing an annual average increase in number emission over the polar cap (70–90° N of 86 × 106 m−2 s−1 (mass emission increase of 23 μg m−2 s−1. This in turn leads to an increase in the natural aerosol optical depth of approximately 23%. In response to changes in aerosol optical depth, the natural component of the aerosol direct forcing over the Arctic polar cap is estimated to be between −0.2 and −0.4 W m−2 for the summer months, which results in a negative feedback on the system. The model predicts that the change in first indirect aerosol effect (cloud albedo effect is approximately a factor of ten greater than the change in direct aerosol forcing although this result is highly uncertain due to the crude representation of Arctic clouds and aerosol-cloud interactions in the model. This study shows that both the natural aerosol direct and first indirect effects are strongly dependent on the surface albedo, highlighting the strong coupling between sea ice, aerosols, Arctic clouds and their radiative effects.

  19. Balancing Radiation and Contrast Media Dose in Single-Pass Abdominal Multidetector CT: Prospective Evaluation of Image Quality.

    Camera, Luigi; Romano, Federica; Liccardo, Immacolata; Liuzzi, Raffaele; Imbriaco, Massimo; Mainenti, Pier Paolo; Pizzuti, Laura Micol; Segreto, Sabrina; Maurea, Simone; Brunetti, Arturo

    2015-11-01

    As both contrast and radiation dose affect the quality of CT images, a constant image quality in abdominal contrast-enhanced multidetector computed tomography (CE-MDCT) could be obtained balancing radiation and contrast media dose according to the age of the patients. Seventy-two (38 Men; 34 women; aged 20-83 years) patients underwent a single-pass abdominal CE-MDCT. Patients were divided into three different age groups: A (20-44 years); B (45-65 years); and C (>65 years). For each group, a different noise index (NI) and contrast media dose (370 mgI/mL) was selected as follows: A (NI, 15; 2.5 mL/kg), B (NI, 12.5; 2 mL/kg), and C (NI, 10; 1.5 mL/kg). Radiation exposure was reported as dose-length product (DLP) in mGy × cm. For quantitative analysis, signal-to-noise (SNR) and contrast-to-noise (CNR) ratios were calculated for both the liver (L) and the abdominal aorta (A). Statistical analysis was performed with a one-way analysis of variance. Standard imaging criteria were used for qualitative analysis. Although peak hepatic enhancement was 152 ± 16, 128 ± 12, and 101 ± 14 Hounsfield units (P contrast media dose (mL) administered were 476 ± 147 and 155 ± 27 for group A, 926 ± 291 and 130 ± 16 for group B, and 1981 ± 451 and 106 ± 15 for group C, respectively (P contrast media dose administered to patients of different age. Copyright © 2015 AUR. Published by Elsevier Inc. All rights reserved.

  20. Dust radiative forcing in snow of the Upper Colorado River Basin: 1. A 6 year record of energy balance, radiation, and dust concentrations

    Painter, Thomas H.; Skiles, S. Mckenzie; Deems, Jeffrey S.; Bryant, Ann C.; Landry, Christopher C.

    2012-07-01

    Dust in snow accelerates snowmelt through its direct reduction of snow albedo and its further indirect reduction of albedo by accelerating the growth of snow grains. Since the westward expansion of the United States that began in the mid-19th century, the mountain snow cover of the Colorado River Basin has been subject to five-fold greater dust loading, largely from the Colorado Plateau and Great Basin. Radiative forcing of snowmelt by dust is not captured by conventional micrometeorological measurements, and must be monitored by a more comprehensive suite of radiation instruments. Here we present a 6 year record of energy balance and detailed radiation measurements in the Senator Beck Basin Study Area, San Juan Mountains, Colorado, USA. Data include broadband irradiance, filtered irradiance, broadband reflected flux, filtered reflected flux, broadband and visible albedo, longwave irradiance, wind speed, relative humidity, and air temperatures. The gradient of the snow surface is monitored weekly and used to correct albedo measurements for geometric effects. The snow is sampled weekly for dust concentrations in plots immediately adjacent to each tower over the melt season. Broadband albedo in the last weeks of snow cover ranged from 0.33 to 0.55 across the 6 years and two sites. Total end of year dust concentration in the top 3 cm of the snow column ranged from 0.23 mg g-1 to 4.16 mg g-1. These measurements enable monitoring and modeling of dust and climate-driven snowmelt forcings in the Upper Colorado River Basin.

  1. Diffuse radiation increases global ecosystem-level water-use efficiency

    Moffat, A. M.; Reichstein, M.; Cescatti, A.; Knohl, A.; Zaehle, S.

    2012-12-01

    Current environmental changes lead not only to rising atmospheric CO2 levels and air temperature but also to changes in air pollution and thus the light quality of the solar radiation reaching the land-surface. While rising CO2 levels are thought to enhance photosynthesis and closure of stomata, thus leading to relative water savings, the effect of diffuse radiation on transpiration by plants is less clear. It has been speculated that the stimulation of photosynthesis by increased levels of diffuse light may be counteracted by higher transpiration and consequently water depletion and drought stress. Ultimately, in water co-limited systems, the overall effect of diffuse radiation will depend on the sensitivity of canopy transpiration versus photosynthesis to diffuse light, i.e. whether water-use efficiency changes with relative levels of diffuse light. Our study shows that water-use efficiency increases significantly with higher fractions of diffuse light. It uses the ecosystem-atmosphere gas-exchange observations obtained with the eddy covariance method at 29 flux tower sites. In contrast to previous global studies, the analysis is based directly on measurements of diffuse radiation. Its effect on water-use efficiency was derived by analyzing the multivariate response of carbon and water fluxes to radiation and air humidity using a purely empirical approach based on artificial neural networks. We infer that per unit change of diffuse fraction the water-use efficiency increases up to 40% depending on diffuse fraction levels and ecosystem type. Hence, in regions with increasing diffuse radiation positive effects on primary production are expected even under conditions where water is co-limiting productivity.

  2. A Global Modeling Study on Carbonaceous Aerosol Microphysical Characteristics and Radiative Effects

    Bauer, S. E.; Menon, S.; Koch, D.; Bond, T. C.; Tsigaridis, K.

    2010-01-01

    Recently, attention has been drawn towards black carbon aerosols as a short-term climate warming mitigation candidate. However the global and regional impacts of the direct, indirect and semi-direct aerosol effects are highly uncertain, due to the complex nature of aerosol evolution and the way that mixed, aged aerosols interact with clouds and radiation. A detailed aerosol microphysical scheme, MATRIX, embedded within the GISS climate model is used in this study to present a quantitative assessment of the impact of microphysical processes involving black carbon, such as emission size distributions and optical properties on aerosol cloud activation and radiative effects. Our best estimate for net direct and indirect aerosol radiative flux change between 1750 and 2000 is -0.56 W/m2. However, the direct and indirect aerosol effects are quite sensitive to the black and organic carbon size distribution and consequential mixing state. The net radiative flux change can vary between -0.32 to -0.75 W/m2 depending on these carbonaceous particle properties at emission. Taking into account internally mixed black carbon particles let us simulate correct aerosol absorption. Absorption of black carbon aerosols is amplified by sulfate and nitrate coatings and, even more strongly, by organic coatings. Black carbon mitigation scenarios generally showed reduced radiative fluxeswhen sources with a large proportion of black carbon, such as diesel, are reduced; however reducing sources with a larger organic carbon component as well, such as bio-fuels, does not necessarily lead to a reduction in positive radiative flux.

  3. Compatibility of different measurement techniques. Long-term global solar radiation observations at Izaña Observatory [Discussion paper

    García Cabrera, Rosa Delia; Cuevas Agulló, Emilio; García Rodríguez, Omaira Elena; Ramos López, Ramón; Romero Campos, Pedro Miguel; Ory Ajamil, Fernando de; Cachorro, Victoria E.; Frutos, Ángel M. de

    2016-01-01

    A 1-year intercomparison of classical and modern radiation and sunshine duration instruments has been performed at Izaña Atmospheric Observatory. We compare global solar radiation (GSR) records measured with a Kipp & Zonen CM-21 pyranometer, taken in the framework of the Baseline Surface Radiation Network, with those measured with a multifilter rotating shadowband radiometer and a bimetallic pyranometer, and with GSR estimated from sunshine duration performed with a CS sunshine recorder.

  4. Forecasting hourly global solar radiation using hybrid k-means and nonlinear autoregressive neural network models

    Benmouiza, Khalil; Cheknane, Ali

    2013-01-01

    Highlights: • An unsupervised clustering algorithm with a neural network model was explored. • The forecasting results of solar radiation time series and the comparison of their performance was simulated. • A new method was proposed combining k-means algorithm and NAR network to provide better prediction results. - Abstract: In this paper, we review our work for forecasting hourly global horizontal solar radiation based on the combination of unsupervised k-means clustering algorithm and artificial neural networks (ANN). k-Means algorithm focused on extracting useful information from the data with the aim of modeling the time series behavior and find patterns of the input space by clustering the data. On the other hand, nonlinear autoregressive (NAR) neural networks are powerful computational models for modeling and forecasting nonlinear time series. Taking the advantage of both methods, a new method was proposed combining k-means algorithm and NAR network to provide better forecasting results

  5. Anomalies and Hawking radiation from the Reissner-Nordstroem black hole with a global monopole

    Wu Shuangqing; Peng Junjin

    2007-01-01

    We extend the work by Iso, Umetsu and Wilczek (2006 Phys. Rev. Lett. 96 151302) to derive the Hawking flux via gauge and gravitational anomalies of a most general two-dimensional non-extremal black hole spacetime with the determinant of its diagonal metric differing from unity √ (-g)1) ≠ 1 and use it to investigate Hawking radiation from the Reissner-Nordstroem black hole with a global monopole by requiring the cancellation of anomalies at the horizon. It is shown that the compensating energy-momentum and gauge fluxes required to cancel gravitational and gauge anomalies at the horizon are precisely equivalent to the (1 + 1)-dimensional thermal fluxes associated with Hawking radiation emanating from the horizon at the Hawking temperature. These fluxes are universally determined by the value of anomalies at the horizon

  6. The Global Statistical Response of the Outer Radiation Belt During Geomagnetic Storms

    Murphy, K. R.; Watt, C. E. J.; Mann, I. R.; Jonathan Rae, I.; Sibeck, D. G.; Boyd, A. J.; Forsyth, C. F.; Turner, D. L.; Claudepierre, S. G.; Baker, D. N.; Spence, H. E.; Reeves, G. D.; Blake, J. B.; Fennell, J.

    2018-05-01

    Using the total radiation belt electron content calculated from Van Allen Probe phase space density, the time-dependent and global response of the outer radiation belt during storms is statistically studied. Using phase space density reduces the impacts of adiabatic changes in the main phase, allowing a separation of adiabatic and nonadiabatic effects and revealing a clear modality and repeatable sequence of events in storm time radiation belt electron dynamics. This sequence exhibits an important first adiabatic invariant (μ)-dependent behavior in the seed (150 MeV/G), relativistic (1,000 MeV/G), and ultrarelativistic (4,000 MeV/G) populations. The outer radiation belt statistically shows an initial phase dominated by loss followed by a second phase of rapid acceleration, while the seed population shows little loss and immediate enhancement. The time sequence of the transition to the acceleration is also strongly μ dependent and occurs at low μ first, appearing to be repeatable from storm to storm.

  7. Global response to solar radiation absorbed by phytoplankton in a coupled climate model

    Patara, Lavinia [Centro Euro-Mediterraneo per i Cambiamenti Climatici (CMCC), Bologna (Italy); Helmholtz Centre for Ocean Research Kiel (GEOMAR), Kiel (Germany); Vichi, Marcello; Masina, Simona [Centro Euro-Mediterraneo per i Cambiamenti Climatici (CMCC), Bologna (Italy); Istituto Nazionale di Geofisica e Vulcanologia (INGV), Centro Euro-Mediterraneo per i Cambiamenti Climatici (CMCC), Bologna (Italy); Fogli, Pier Giuseppe [Centro Euro-Mediterraneo per i Cambiamenti Climatici (CMCC), Bologna (Italy); Manzini, Elisa [Centro Euro-Mediterraneo per i Cambiamenti Climatici (CMCC), Bologna (Italy); Max-Planck-Institut fuer Meteorologie, Hamburg (Germany)

    2012-10-15

    The global climate response to solar radiation absorbed by phytoplankton is investigated by performing multi-century simulations with a coupled ocean-atmosphere-biogeochemistry model. The absorption of solar radiation by phytoplankton increases radiative heating in the near-surface ocean and raises sea surface temperature (SST) by overall {approx}0.5 C. The resulting increase in evaporation enhances specific atmospheric humidity by 2-5%, thereby increasing the Earth's greenhouse effect and the atmospheric temperatures. The Hadley Cell exhibits a weakening and poleward expansion, therefore reducing cloudiness at subtropical-middle latitudes and increasing it at tropical latitudes except near the Equator. Higher SST at polar latitudes reduces sea ice cover and albedo, thereby increasing the high-latitude ocean absorption of solar radiation. Changes in the atmospheric baroclinicity cause a poleward intensification of mid-latitude westerly winds in both hemispheres. As a result, the North Atlantic Ocean meridional overturning circulation extends more northward, and the equatorward Ekman transport is enhanced in the Southern Ocean. The combination of local and dynamical processes decreases upper-ocean heat content in the Tropics and in the subpolar Southern Ocean, and increases it at middle latitudes. This study highlights the relevance of coupled ocean-atmosphere processes in the global climate response to phytoplankton solar absorption. Given that simulated impacts of phytoplankton on physical climate are within the range of natural climate variability, this study suggests the importance of phytoplankton as an internal constituent of the Earth's climate and its potential role in participating in its long-term climate adjustments. (orig.)

  8. Unraveling the global microRNAome responses to ionizing radiation in human embryonic stem cells.

    Mykyta V Sokolov

    Full Text Available MicroRNAs (miRNA comprise a group of short ribonucleic acid molecules implicated in regulation of key biological processes and functions at the post-transcriptional level. Ionizing radiation (IR causes DNA damage and generally triggers cellular stress response. However, the role of miRNAs in IR-induced response in human embryonic stem cells (hESC has not been defined yet. Here, by using system biology approaches, we show for the first time, that miRNAome undergoes global alterations in hESC (H1 and H9 lines after IR. Interrogation of expression levels of 1,090 miRNA species in irradiated hESC showed statistically significant changes in 54 genes following 1 Gy of X-ray exposures; global miRNAome alterations were found to be highly temporally and cell line--dependent in hESC. Time-course studies showed that the 16 hr miRNAome radiation response of hESC is much more robust compared to 2 hr-response signature (only eight genes, and may be involved in regulating the cell cycle. Quantitative real-time PCR performed on some miRNA species confirms the robustness of our miRNA microarray platform. Positive regulation of differentiation-, cell cycle-, ion transport- and endomembrane system-related processes were predicted to be negatively affected by miRNAome changes in irradiated hESC. Our findings reveal a fundamental role of miRNAome in modulating the radiation response, and identify novel molecular targets of radiation in hESC.

  9. Global response to solar radiation absorbed by phytoplankton in a coupled climate model

    Patara, Lavinia; Vichi, Marcello; Masina, Simona; Fogli, Pier Giuseppe; Manzini, Elisa

    2012-01-01

    The global climate response to solar radiation absorbed by phytoplankton is investigated by performing multi-century simulations with a coupled ocean-atmosphere-biogeochemistry model. The absorption of solar radiation by phytoplankton increases radiative heating in the near-surface ocean and raises sea surface temperature (SST) by overall ∼0.5 C. The resulting increase in evaporation enhances specific atmospheric humidity by 2-5%, thereby increasing the Earth's greenhouse effect and the atmospheric temperatures. The Hadley Cell exhibits a weakening and poleward expansion, therefore reducing cloudiness at subtropical-middle latitudes and increasing it at tropical latitudes except near the Equator. Higher SST at polar latitudes reduces sea ice cover and albedo, thereby increasing the high-latitude ocean absorption of solar radiation. Changes in the atmospheric baroclinicity cause a poleward intensification of mid-latitude westerly winds in both hemispheres. As a result, the North Atlantic Ocean meridional overturning circulation extends more northward, and the equatorward Ekman transport is enhanced in the Southern Ocean. The combination of local and dynamical processes decreases upper-ocean heat content in the Tropics and in the subpolar Southern Ocean, and increases it at middle latitudes. This study highlights the relevance of coupled ocean-atmosphere processes in the global climate response to phytoplankton solar absorption. Given that simulated impacts of phytoplankton on physical climate are within the range of natural climate variability, this study suggests the importance of phytoplankton as an internal constituent of the Earth's climate and its potential role in participating in its long-term climate adjustments. (orig.)

  10. Global solar radiation: Multiple on-site assessments in Abu Dhabi, UAE

    El Chaar, Lana; Lamont, Lisa A. [Petroleum Institute, Electrical Engineering Department, P.O. Box 2533, Abu Dhabi (United Arab Emirates)

    2010-07-15

    Renewable energy technology and in particular solar energy is being considered worldwide due to the fluctuations in oil prices, global warming and the growing demand for energy supply. This paper investigates the climate conditions available in the United Arab Emirates (UAE) in particular Abu Dhabi to implement Photovoltaic (PV) technology. Measured solar radiation was analyzed for five different geographical locations to ensure the suitability of this region. Hourly, daily and monthly global horizontal irradiation (GHI) were collected and processed. Statistical methods were used to evaluate the computed GHI and showed high values especially during the summer period. Moreover, clearness index was calculated to investigate the frequency of cloudy sky days and results have shown a high percentage of clear days during the year. This paper highlights a promising future for Abu Dhabi in the solar energy sector and in particular Photovoltaic (PV) technology. (author)

  11. Strong relationship between DMS and the solar radiation dose over the global surface ocean.

    Vallina, Sergio M; Simó, Rafel

    2007-01-26

    Marine biogenic dimethylsulfide (DMS) is the main natural source of tropospheric sulfur, which may play a key role in cloud formation and albedo over the remote ocean. Through a global data analysis, we found that DMS concentrations are highly positively correlated with the solar radiation dose in the upper mixed layer of the open ocean, irrespective of latitude, plankton biomass, or temperature. This is a necessary condition for the feasibility of a negative feedback in which light-attenuating DMS emissions are in turn driven by the light dose received by the pelagic ecosystem.

  12. Data Descriptor: TerraClimate, a high-resolution global dataset of monthly climate and climatic water balance from 1958-2015

    John T. Abatzoglou; Solomon Z. Dobrowski; Sean A. Parks; Katherine C. Hegewisch

    2018-01-01

    We present TerraClimate, a dataset of high-spatial resolution (1/24°, ~4-km) monthly climate and climatic water balance for global terrestrial surfaces from 1958–2015. TerraClimate uses climatically aided interpolation, combining high-spatial resolution climatological normals from the WorldClim dataset, with coarser resolution time varying (i.e., monthly) data from...

  13. CORRECTION OF GLOBAL AND REFLEX RADIATION VALUES MEASURED ABOVE THE LAKE BALATON

    Laszlo Menyhart

    2014-03-01

    Full Text Available Albedo measurements have been carried out since 2007 above the Lake Balaton near Keszthely and Siofok. It turned out that a systematic offset error was superposed to both the global and the reflex radiation. The value of this systematic error was approximately constant per pyranometer within a year but on the other hand it varied from year to year and from pyranometer to pyranometer. In this paper the values of this systematic errors were determined with two different methods. The difference between the values measured at night-time and the intrinsic thermal offset error of pyranometers were examined with both methods. The base of the first method is the empirical observation, that the values measured at night-time by a global radiometer are typically negative whereas by a reflex radiometer are typically positive. The substance of the second method is utilizing the air temperature measured within 1 as well as 5 hours before the radiation measuring to +select the fully overcast nights, when the thermal offset error of the global radiometer is zero. In addition, the cases where the thermal offset error of the reflex radiometer is zero were selected on the basis of the difference between water and air temperature. When the thermal offset error is zero the measured value is equal to the systematic error. Comparing the results of the two methods showed that the systematic error of the global radiometer were determined with uncertainty of 1 Wm–2, whereas that of the reflex radiometer with uncertainty of 2 Wm–2. The calibration constants were recalculated from the values being in the calibration reports taking the systematic errors into account.

  14. Analysis of factors that affect shoulder balance after correction surgery in scoliosis: a global analysis of all the curvature types.

    Hong, Jae-Young; Suh, Seung-Woo; Modi, Hitesh N; Yang, Jae-Hyuk; Park, Si-Young

    2013-06-01

    To identify factors that can affect postoperative shoulder balance in AIS. 89 adolescent idiopathic scoliosis patients with six types of curvatures who underwent surgery were included in this study. Whole spine antero-posterior and lateral radiographs were obtained pre- and postoperatively. In radiograms, shape and changes in curvatures were analyzed. In addition, four shoulder parameters and coronal balance were analyzed in an effort to identify factors significantly related to postoperative shoulder balance. In general, all the four shoulder parameters (CHD, CA, CRID, RSH) were slightly increased at final follow up (t test, P shoulder parameters were not significantly different between each curvature types (ANOVA, P > 0.05). Moreover, no significant differences of pre- and postoperative shoulder level between different level of proximal fusion groups (ANOVA, P > 0.05) existed. In the analysis of coronal curvature changes, no difference was observed in every individual coronal curvatures between improved shoulder balance and aggravated groups (P > 0.05). However, the middle to distal curve change ratio was significantly lower in patients with aggravated shoulder balance (P shoulder imbalance showed the higher chance of aggravation after surgery with similar postoperative changes (P shoulder balance. In addition, preoperative shoulder level difference can be a determinant of postoperative shoulder balance.

  15. Empirical models for the estimation of global solar radiation with sunshine hours on horizontal surface in various cities of Pakistan

    Gadiwala, M.S.; Usman, A.; Akhtar, M.; Jamil, K.

    2013-01-01

    In developing countries like Pakistan the global solar radiation and its components is not available for all locations due to which there is a requirement of using different models for the estimation of global solar radiation that use climatological parameters of the locations. Only five long-period locations data of solar radiation data is available in Pakistan (Karachi, Quetta, Lahore, Multan and Peshawar). These locations almost encompass the different geographical features of Pakistan. For this reason in this study the Mean monthly global solar radiation has been estimated using empirical models of Angstrom, FAO, Glover Mc-Culloch, Sangeeta & Tiwari for the diversity of approach and use of climatic and geographical parameters. Empirical constants for these models have been estimated and the results obtained by these models have been tested statistically. The results show encouraging agreement between estimated and measured values. The outcome of these empirical models will assist the researchers working on solar energy estimation of the location having similar conditions

  16. Assessment of global solar radiation to examine the best locations to install a PV system in Tunisia

    Belkilani, Kaouther; Ben Othman, Afef; Besbes, Mongi

    2018-02-01

    The study of the solar radiation is the starting point of any investigation for a new energy, to study and search the best location to install a PV system. A very important factor in the assessment of solar potential is the availability of data for global solar radiation that must be coherent and of high quality. In this paper, we analyze the estimation result of the monthly global solar radiation for three different locations, Bizerte in Northern Tunisia, Kairouan in Middle Eastern Tunisia, and Tozeur in Southern Tunisia, measured on the surface by the National Institute of Meteorology and the meteorological year irradiation based on satellite imagery result PVGIS radiation databases. To get the right measurements with minimum error, we propose a numerical model used to calculate the global solar radiation in the indicated three sites. The results show that the model can estimate the global solar radiation (kWh/m²) at a specific station and over most area of Tunisia. The model gives a good estimation for solar radiation where error between the measured values and those calculated are negligible.

  17. Global radiation damage at 300 and 260 K with dose rates approaching 1 MGy s{sup −1}

    Warkentin, Matthew; Badeau, Ryan; Hopkins, Jesse B. [Cornell University, Ithaca, NY 14853 (United States); Mulichak, Anne M.; Keefe, Lisa J. [Argonne National Laboratory, Argonne, IL 60439 (United States); Thorne, Robert E., E-mail: ret6@cornell.edu [Cornell University, Ithaca, NY 14853 (United States)

    2012-02-01

    Approximately half of global radiation damage to thaumatin crystals can be outrun at 260 K if data are collected in less than 1 s. Global radiation damage to 19 thaumatin crystals has been measured using dose rates from 3 to 680 kGy s{sup −1}. At room temperature damage per unit dose appears to be roughly independent of dose rate, suggesting that the timescales for important damage processes are less than ∼1 s. However, at T = 260 K approximately half of the global damage manifested at dose rates of ∼10 kGy s{sup −1} can be outrun by collecting data at 680 kGy s{sup −1}. Appreciable sample-to-sample variability in global radiation sensitivity at fixed dose rate is observed. This variability cannot be accounted for by errors in dose calculation, crystal slippage or the size of the data sets in the assay.

  18. The structure of the radiation balance on a sandy surface: case the Błędów desert, Silesian Upland

    Caputa Zbigniew

    2016-06-01

    Full Text Available Comprehensive environmental studies taking under consideration the structure of the radiation balance during the vegetation growing seasons of 2001 and 2002 were carried out on the open sandy surface of the area called the Błędów ‘desert’ located on Silesian Upland. The research in each site covered the composition of plant species, their age and height, the condition of the substratum, the composition and structure of the soil and the meteorological conditions with elements of the radiation balance. The article presents some part of the research on meteorological elements and their impact on ecosystem. Special attention was devoted to radiation conditions on the open sandy surface in the context of the formation of BSC (biological soil crust. Having presumed that the values obtained on the grassy surface constituted 100%, the values of radiation reflection measured on the open sandy surface were 185% higher and the values of net longwave radiation were 105% higher in day time and 137% in night time. Values of net radiation of about 63% lower were observed on the sandy surface during a typical sunny summer day. It was found that a strong irradiation of the sandy surface (26 MJ·m–2d–1 creates extremely difficult conditions for the initiation of the process of ecosystem formation (including BSC or plant succession. The elements of the radiation balance, net radiation, albedo and temperature of the open sandy surface were represented quantitatively. The test surfaces were classified based on the value of the albedo: group I with low albedo values, up to 0.15 (spore-bearing plants on a dark surface, including BSC; group II with mean values of the albedo from 0.16 to 0.24 (spore-bearing plants and seed on a dark grey surface; and group III with high albedo values, above 0.25 (plants growing on bare or loose sands.

  19. Assessment of Global Cloud Datasets from Satellites: Project and Database Initiated by the GEWEX Radiation Panel

    Stubenrauch, C. J.; Rossow, W. B.; Kinne, S.; Ackerman, S.; Cesana, G.; Chepfer, H.; Getzewich, B.; Di Girolamo, L.; Guignard, A.; Heidinger, A.; hide

    2012-01-01

    Clouds cover about 70% of the Earth's surface and play a dominant role in the energy and water cycle of our planet. Only satellite observations provide a continuous survey of the state of the atmosphere over the whole globe and across the wide range of spatial and temporal scales that comprise weather and climate variability. Satellite cloud data records now exceed more than 25 years in length. However, climatologies compiled from different satellite datasets can exhibit systematic biases. Questions therefore arise as to the accuracy and limitations of the various sensors. The Global Energy and Water cycle Experiment (GEWEX) Cloud Assessment, initiated in 2005 by the GEWEX Radiation Panel, provided the first coordinated intercomparison of publically available, standard global cloud products (gridded, monthly statistics) retrieved from measurements of multi-spectral imagers (some with multiangle view and polarization capabilities), IR sounders and lidar. Cloud properties under study include cloud amount, cloud height (in terms of pressure, temperature or altitude), cloud radiative properties (optical depth or emissivity), cloud thermodynamic phase and bulk microphysical properties (effective particle size and water path). Differences in average cloud properties, especially in the amount of high-level clouds, are mostly explained by the inherent instrument measurement capability for detecting and/or identifying optically thin cirrus, especially when overlying low-level clouds. The study of long-term variations with these datasets requires consideration of many factors. A monthly, gridded database, in common format, facilitates further assessments, climate studies and the evaluation of climate models.

  20. Global Solar radiation in Spain from Satellite Images; Radiacion Solar Global en la Espana Peninsular a partir de images de satelite

    Ramirez Santigosa, L.; Mora Lopez, L.; Sidrach de Cardona Ortin, M.; Navarro Fernandez, A. A.; Varela conde, M.; Cruz Echeandia, M. de la

    2003-07-01

    In the context of the present work a series of algorithms of calculation of the solar radiation from satellite images has been developed. These models, have been applied to three years of images of the Meteosat satellite and the results of the treatment have been extrapolated to long term. For the development of the models of solar radiation registered in ground stations have been used, corresponding all of them to localities of peninsular Spain and the Balearic ones. The maximum periods of data available have been used, supposing in most of the cases periods of between 6 and 9 years. From the results has a year type of images of global solar radiation on horizontal surface. The original resolution of the image of 7x7 km in the study latitudes, has been revaluate to 5x5 km. This supposes to have a value of the typical radiation for every day of the year, each 5x5 km in the study territory. This information, supposes an important advance as far as the knowledge of the space distribution of the radiation solar,impossible to reach about alternative methods. Doubtlessly, the precision of the provided values is not comparable with pyranometric measures in a concrete localise, but it provides a very valid indicator in places in which, it not had previous information. In addition to the radiation maps, tables of the global solar radiation have been prepared on different inclinations, from the global radiation on horizontal surface calculated for every day of the year and in each pixel of the image. (Author) 24 refs.

  1. Thermoregulation of water foraging honeybees--balancing of endothermic activity with radiative heat gain and functional requirements.

    Kovac, Helmut; Stabentheiner, Anton; Schmaranzer, Sigurd

    2010-12-01

    Foraging honeybees are subjected to considerable variations of microclimatic conditions challenging their thermoregulatory ability. Solar heat is a gain in the cold but may be a burden in the heat. We investigated the balancing of endothermic activity with radiative heat gain and physiological functions of water foraging Apis mellifera carnica honeybees in the whole range of ambient temperatures (T(a)) and solar radiation they are likely to be exposed in their natural environment in Middle Europe. The mean thorax temperature (T(th)) during foraging stays was regulated at a constantly high level (37.0-38.5 °C) in a broad range of T(a) (3-30 °C). At warmer conditions (T(a)=30-39 °C) T(th) increased to a maximal level of 45.3 °C. The endothermic temperature excess (difference of T(body)-T(a) of living and dead bees) was used to assess the endogenously generated temperature elevation as a correlate of energy turnover. Up to a T(a) of ∼30 °C bees used solar heat gain for a double purpose: to reduce energetic expenditure and to increase T(th) by about 1-3 °C to improve force production of flight muscles. At higher T(a) they exhibited cooling efforts to get rid of excess heat. A high T(th) also allowed regulation of the head temperature high enough to guarantee proper function of the bees' suction pump even at low T(a). This shortened the foraging stays and this way reduced energetic costs. With decreasing T(a) bees also reduced arrival body weight and crop loading to do both minimize costs and optimize flight performance. Copyright © 2010 Elsevier Ltd. All rights reserved.

  2. Contributions of projected land use to global radiative forcing ascribed to local sources

    Ward, D. S.; Mahowald, N. M.; Kloster, S.

    2013-12-01

    With global demand for food expected to dramatically increase and put additional pressures on natural lands, there is a need to understand the environmental impacts of land use and land cover change (LULCC). Previous studies have shown that the magnitude and even the sign of the radiative forcing (RF) of biogeophysical effects from LULCC depends on the latitude and forest ecology of the disturbed region. Here we ascribe the contributions to the global RF by land-use related anthropogenic activities to their local sources, organized on a grid of 1.9 degrees latitude by 2.5 degrees longitude. We use RF estimates for the year 2100, using five future LULCC projections, computed from simulations with the National Center for Atmospheric Research Community Land Model and Community Atmosphere Models and additional offline analyses. Our definition of the LULCC RF includes changes to terrestrial carbon storage, methane and nitrous oxide emissions, atmospheric chemistry, aerosol emissions, and surface albedo. We ascribe the RF to gridded locations based on LULCC-related emissions of relevant trace gases and aerosols, including emissions from fires. We find that the largest contributions to the global RF in year 2100 from LULCC originate in the tropics for all future scenarios. In fact, LULCC is the largest tropical source of anthropogenic RF. The LULCC RF in the tropics is dominated by emissions of CO2 from deforestation and methane emissions from livestock and soils. Land surface albedo change is rarely the dominant forcing agent in any of the future LULCC projections, at any location. By combining the five future scenarios we find that deforested area at a specific tropical location can be used to predict the contribution to global RF from LULCC at that location (the relationship does not hold as well in the extratropics). This information could support global efforts like REDD (Reducing Emissions from Deforestation and Forest Degradation), that aim to reduce greenhouse gas

  3. Toward Improving the Representation of Convection and Cloud-Radiation Interaction for Global Climate Simulations

    Wu, X.; Song, X.; Deng, L.; Park, S.; Liang, X.; Zhang, G. J.

    2006-05-01

    Despite the significant progress made in developing general circulation models (GCMs), major uncertainties related to the parameterization of convection, cloud and radiation processes still remain. The current GCM credibility of seasonal-interannual climate predictions or climate change projections is limited. In particular, the following long-standing biases, common to most GCMs, need to be reduced: 1) over-prediction of high-level cloud amounts although GCMs realistically simulating the global radiation budget; 2) general failure to reproduce the seasonal variation and migration of the ITCZ precipitation; 3) incomplete representation of the Madden-Julian Oscillation (MJO); and 4) false production of an excessive cold tone of sea surface temperature across the Pacific basin and a double ITCZ structure in precipitation when the atmosphere and ocean are fully coupled. The development of cloud-resolving models (CRMs) provides a unique opportunity to address issues aimed to reduce these biases. The statistical analysis of CRM simulations together with the theoretical consideration of subgrid-scale processes will enable us to develop physically-based parameterization of convection, clouds, radiation and their interactions.

  4. A method for daily global solar radiation estimation from two instantaneous values using MODIS atmospheric products

    Xu, Xiaojun; Du, Huaqiang; Zhou, Guomo; Mao, Fangjie; Li, Pingheng; Fan, Weiliang; Zhu, Dien

    2016-01-01

    Accurate information on the temporal and spatial distributions of solar radiation is very important in many scientific fields. In this study, instantaneous solar irradiances on a horizontal surface at 10:30 and 13:30 local time (LT) were calculated from Moderate Resolution Imaging Spectroradiometer (MODIS) atmospheric data products with relatively high spatial resolution using a solar radiation model. These solar irradiances were combined to derive half-hourly averages of solar irradiance (HASI) and daily global solar radiation (GSR) on a horizontal surface using linear interpolation, piecewise linear regression, and quadratic polynomial regression. Compared with field observations, the HASI were estimated accurately when the total cloud fraction (TCF) was 0.6. Overall, the daily GSR estimated in this study was better than that estimated by the Modern-Era Retrospective Analysis for Research and Applications (MERRA) reanalysis of NASA. The daily GSR estimated in this study was underestimated, whereas it was overestimated by MERRA. The combination of the daily GSR estimates of this study and MERRA offers a simple and feasible technique for reducing uncertainty in daily GSR estimates. - Highlights: • Daily GSR is integrated from two observations from the MODIS products. • Daily GSR from the MODIS products is underestimated. • Biases were attributed primarily to variations in the total cloud percent. • Combining daily GSR estimates from the MODIS and the MERRA increases accuracy.

  5. Establishing a Global Radiation Oncology Collaboration in Education (GRaCE): Objectives and priorities.

    Turner, Sandra; Eriksen, Jesper G; Trotter, Theresa; Verfaillie, Christine; Benstead, Kim; Giuliani, Meredith; Poortmans, Philip; Holt, Tanya; Brennan, Sean; Pötter, Richard

    2015-10-01

    Representatives from countries and regions world-wide who have implemented modern competency-based radiation- or clinical oncology curricula for training medical specialists, met to determine the feasibility and value of an ongoing international collaboration. In this forum, educational leaders from the ESTRO School, encompassing many European countries adopting the ESTRO Core Curriculum, and clinician educators from Canada, Denmark, the United Kingdom, Australia and New Zealand considered the training and educational arrangements within their jurisdictions, identifying similarities and challenges between programs. Common areas of educational interest and need were defined, which included development of new competency statements and assessment tools, and the application of the latter. The group concluded that such an international cooperation, which might expand to include others with similar goals, would provide a valuable vehicle to ensure training program currency, through sharing of resources and expertise, and enhance high quality radiation oncology education. Potential projects for the Global Radiation Oncology Collaboration in Education (GRaCE) were agreed upon, as was a strategy designed to maintain momentum. This paper describes the rationale for establishing this collaboration, presents a comparative view of training in the jurisdictions represented, and reports early goals and priorities. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  6. Installation of a variable-angle spectrometer system for monitoring diffuse and global solar radiation

    Ormachea, O.; Abrahamse, A.; Tolavi, N.; Romero, F.; Urquidi, O.; Pearce, J. M.; Andrews, R.

    2013-11-01

    We report on the design and installation of a spectrometer system for monitoring solar radiation in Cochabamba, Bolivia. Both the light intensity and the spectral distribution affect the power produced by a photovoltaic device. Local variations in the solar spectrum (especially compared to the AM1.5 standard) may have important implications for device optimization and energy yield estimation. The spectrometer system, based on an Ocean Optics USB4000 (300-900nm) spectrometer, was designed to increase functionality. Typically systems only record the global horizontal radiation. Our system moves a fiber-optic cable 0-90 degrees and takes measurements in 9 degree increments. Additionally, a shadow band allows measurement of the diffuse component of the radiation at each position. The electronic controls utilize an Arduino UNO microcontroller to synchronizes the movement of two PAP bipolar (stepper) motors with the activation of the spectrometer via an external trigger. The spectrometer was factory calibrated for wavelength and calibrated for absolute irradiance using a Sellarnet SL1-Cal light source. We present preliminary results from data taken March-June, 2013, and comment on implications for PV devices in Cochabamba.

  7. Measurement of Global Solar Radiation data using Raspberry Pi and its estimation using Genetic Algorithm

    Priya S.Shanmuga

    2018-01-01

    Full Text Available The demand for more efficient and environmentally benign, non-conventional sources of energy came into picture due to increasing demands for human comforts. Solar energy is now the ultimate option. In this paper, the instruments used to measure the solar radiation at Innovation Centre, MIT Manipal were connected to a Raspberry Pi to access the data remotely. Genetic Algorithms were formulated, so that the monthly mean global solar radiation in Manipal can be effectively estimated. Meteorological data such as humidity, temperature, wind speed, etc. were used as inputs to train the networks. A successful network was made between the data loggers and the Raspberry Pi. The data collected by the data loggers from the devices are transmitted to the Raspberry Pi which in turn sends the data to an internal server. The Raspberry Pi can be accessed using any SSH client such as PuTTY. The meteorological data was collected for the years 2010-2014 in order to formulate the Artificial Intelligence models. The validity of the formulated models were checked by comparing the measured data with the estimated data using tools such as RMSE, correlation coefficient, etc. The modelling of solar radiation using GA was carried out in GeneXpro tools version 5.0.

  8. Temperature differences within the detector of the Robertson-Berger sunburn meter, model 500, compared to global radiation

    Kjeldstad, Berit; Grandum, Oddbjorn

    1993-11-01

    The Robertson-Berger sunburn meter, model 500, has no temperature compensation, and the effect of temperature on the instrument response has been investigated and discussed in several reports. It is recommended to control the temperature of the detector or at least measure it. The temperature sensor is recommended to be positioned within the detector unit. We have measured the temperature at three different positions in the detector: At the edge of the green filter where the phosphor layer is placed; at the glass tube covering the cathode; and, finally, the air temperature inside the instrument. These measurements have been performed outdoors since July 1991, with corresponding measurements of the global and direct solar radiation. There was no difference between the temperature of the glasstube covering the cathode and the air inside the instrument, at any radiation level. However, there was a difference between the green filter and the two others. The difference is linearly dependent on the amount of global radiation. The temperature difference, (Delta) T (temperature between the green filter and the air inside the sensor), increased 0.8 degree(s)C when the global irradiation increased by 100 W/m2. At maximum global radiation in Trondheim (latitude 63.4 degree(s)N) (Delta) T was approximately 5 - 6 K when the global radiation was about 700 W/m2. This was valid for temperatures between 7 degree(s)C and 30 degree(s)C. Only clear days were evaluated.

  9. Power spectral density and scaling exponent of high frequency global solar radiation sequences

    Calif, Rudy; Schmitt, François G.; Huang, Yongxiang

    2013-04-01

    The part of the solar power production from photovlotaïcs systems is constantly increasing in the electric grids. Solar energy converter devices such as photovoltaic cells are very sensitive to instantaneous solar radiation fluctuations. Thus rapid variation of solar radiation due to changes in the local meteorological condition can induce large amplitude fluctuations of the produced electrical power and reduce the overall efficiency of the system. When large amount of photovoltaic electricity is send into a weak or small electricity network such as island network, the electric grid security can be in jeopardy due to these power fluctuations. The integration of this energy in the electrical network remains a major challenge, due to the high variability of solar radiation in time and space. To palliate these difficulties, it is essential to identify the characteristic of these fluctuations in order to anticipate the eventuality of power shortage or power surge. The objective of this study is to present an approach based on Empirical Mode Decomposition (EMD) and Hilbert-Huang Transform (HHT) to highlight the scaling properties of global solar irradiance data G(t). The scale of invariance is detected on this dataset using the Empirical Mode Decomposition in association with arbitrary-order Hilbert spectral analysis, a generalization of (HHT) or Hilbert Spectral Analysis (HSA). The first step is the EMD, consists in decomposing the normalized global solar radiation data G'(t) into several Intrinsic Mode Functions (IMF) Ci(t) without giving an a priori basis. Consequently, the normalized original solar radiation sequence G'(t) can be written as a sum of Ci(t) with a residual rn. From all IMF modes, a joint PDF P(f,A) of locally and instantaneous frequency f and amplitude A, is estimated. To characterize the scaling behavior in amplitude-frequency space, an arbitrary-order Hilbert marginal spectrum is defined to: Iq(f) = 0 P (f,A)A dA (1) with q × 0 In case of scale

  10. Globalization

    Tulio Rosembuj

    2006-12-01

    Full Text Available There is no singular globalization, nor is the result of an individual agent. We could start by saying that global action has different angles and subjects who perform it are different, as well as its objectives. The global is an invisible invasion of materials and immediate effects.

  11. Globalization

    Tulio Rosembuj

    2006-01-01

    There is no singular globalization, nor is the result of an individual agent. We could start by saying that global action has different angles and subjects who perform it are different, as well as its objectives. The global is an invisible invasion of materials and immediate effects.

  12. Component greenhouse gas fluxes and radiative balance from two deltaic marshes in Louisiana: Pairing chamber techniques and eddy covariance

    Krauss, Ken W.; Holm, Guerry O.; Perez, Brian C.; McWhorter, David E.; Cormier, Nicole; Moss, Rebecca; Johnson, Darren; Neubauer, Scott C; Raynie, Richard C

    2016-01-01

    Coastal marshes take up atmospheric CO2 while emitting CO2, CH4, and N2O. This ability to sequester carbon (C) is much greater for wetlands on a per-area basis than from most ecosystems, facilitating scientific, political, and economic interest in their value as greenhouse gas sinks. However, the greenhouse gas balance of Gulf of Mexico wetlands is particularly understudied. We describe the net ecosystem exchange (NEEc) of CO2 and CH4 using eddy covariance (EC) in comparison with fluxes of CO2, CH4, and N2O using chambers from brackish and freshwater marshes in Louisiana, USA. From EC, we found that 182 g C m-2 y-1 was lost through NEEc from the brackish marsh. Of this, 11 g C m-2 y-1 resulted from net CH4 emissions and the remaining 171 g C m-2 y-1 resulted from net CO2 emissions. In contrast, -290 g C m2 y-1 was taken up through NEEc by the freshwater marsh, with 47 g C m-2 y-1 emitted as CH4 and -337 g C m-2 y-1 taken up as CO2. From chambers, we discovered that neither site had large fluxes of N2O. Sustained-flux greenhouse gas accounting metrics indicated that both marshes had a positive (warming) radiative balance, with the brackish marsh having a substantially greater warming effect than the freshwater marsh. That net respiratory emissions of CO2 and CH4 as estimated through chamber techniques were 2-4 times different from emissions estimated through EC requires additional understanding of the artifacts created by different spatial and temporal sampling footprints between techniques.

  13. Cis- and trans-perfluorodecalin: Infrared spectra, radiative efficiency and global warming potential

    Le Bris, Karine; DeZeeuw, Jasmine; Godin, Paul J.; Strong, Kimberly

    2017-12-01

    Perfluorodecalin (PFD) is a molecule used in various medical applications for its capacity to dissolve gases. This potent greenhouse gas was detected for the first time in the atmosphere in 2005. We present infrared absorption cross-section spectra of a pure vapour of cis- and trans-perfluorodecalin at a resolution of 0.1 cm-1. Measurements were performed in the 560-3000 cm-1 spectral range using Fourier transform spectroscopy. The spectra have been compared with previous experimental data and theoretical calculations by density functional theory. The new experimental absorption cross-sections have been used to calculate a lifetime-corrected radiative efficiency at 300 K of 0.62 W m-2 ppb-1 and 0.57 W.m-2.ppb-1 for the cis and trans isomers respectively. This leads to a 100-year time horizon global warming potential of 8030 for cis-PFD and 7440 for trans-PFD.

  14. ARTIFICIAL NEURAL NETWORK AND WAVELET DECOMPOSITION IN THE FORECAST OF GLOBAL HORIZONTAL SOLAR RADIATION

    Luiz Albino Teixeira Júnior

    2015-04-01

    Full Text Available This paper proposes a method (denoted by WD-ANN that combines the Artificial Neural Networks (ANN and the Wavelet Decomposition (WD to generate short-term global horizontal solar radiation forecasting, which is an essential information for evaluating the electrical power generated from the conversion of solar energy into electrical energy. The WD-ANN method consists of two basic steps: firstly, it is performed the decomposition of level p of the time series of interest, generating p + 1 wavelet orthonormal components; secondly, the p + 1 wavelet orthonormal components (generated in the step 1 are inserted simultaneously into an ANN in order to generate short-term forecasting. The results showed that the proposed method (WD-ANN improved substantially the performance over the (traditional ANN method.

  15. Concentrator photovoltaic module architectures with capabilities for capture and conversion of full global solar radiation

    Lee, Kyu Tae

    2016-12-06

    Emerging classes ofconcentrator photovoltaic (CPV) modules reach efficiencies that are far greater than those of even the highest performance flat-plate PV technologies, with architectures that have the potential to provide the lowest cost of energy in locations with high direct normal irradiance (DNI). A disadvantage is their inability to effectively use diffuse sunlight, thereby constraining widespread geographic deployment and limiting performance even under the most favorable DNI conditions. This study introduces a module design that integrates capabilities in flat-plate PV directly with the most sophisticated CPV technologies, for capture of both direct and diffuse sunlight, thereby achieving efficiency in PV conversion of the global solar radiation. Specific examples of this scheme exploit commodity silicon (Si) cells integrated with two different CPV module designs, where they capture light that is not efficiently directed by the concentrator optics onto large-scale arrays of miniature multijunction (MJ) solar cells that use advanced III-V semiconductor technologies. In this CPV scheme (

  16. Tectonic collision and uplift of Wallacea triggered the global songbird radiation

    Moyle, Robert G.; Oliveros, Carl H.; Andersen, Michael J.; Hosner, Peter A.; Benz, Brett W.; Manthey, Joseph D.; Travers, Scott L.; Brown, Rafe M.; Faircloth, Brant C.

    2016-08-01

    Songbirds (oscine passerines) are the most species-rich and cosmopolitan bird group, comprising almost half of global avian diversity. Songbirds originated in Australia, but the evolutionary trajectory from a single species in an isolated continent to worldwide proliferation is poorly understood. Here, we combine the first comprehensive genome-scale DNA sequence data set for songbirds, fossil-based time calibrations, and geologically informed biogeographic reconstructions to provide a well-supported evolutionary hypothesis for the group. We show that songbird diversification began in the Oligocene, but accelerated in the early Miocene, at approximately half the age of most previous estimates. This burst of diversification occurred coincident with extensive island formation in Wallacea, which provided the first dispersal corridor out of Australia, and resulted in independent waves of songbird expansion through Asia to the rest of the globe. Our results reconcile songbird evolution with Earth history and link a major radiation of terrestrial biodiversity to early diversification within an isolated Australian continent.

  17. Concentrator photovoltaic module architectures with capabilities for capture and conversion of full global solar radiation

    Lee, Kyu Tae; Yao, Yuan; He, Junwen; Fisher, Brent; Sheng, Xing; Lumb, Matthew; Xu, Lu; Anderson, Mikayla A.; Scheiman, David; Han, Seungyong; Kang, Yongseon; Gumus, Abdurrahman; Bahabry, Rabab R.; Lee, Jung Woo; Paik, Ungyu; Bronstein, Noah D.; Alivisatos, A. Paul; Meitl, Matthew; Burroughs, Scott; Hussain, Muhammad Mustafa; Lee, Jeong Chul; Nuzzo, Ralph G.; Rogers, John A.

    2016-01-01

    Emerging classes ofconcentrator photovoltaic (CPV) modules reach efficiencies that are far greater than those of even the highest performance flat-plate PV technologies, with architectures that have the potential to provide the lowest cost of energy in locations with high direct normal irradiance (DNI). A disadvantage is their inability to effectively use diffuse sunlight, thereby constraining widespread geographic deployment and limiting performance even under the most favorable DNI conditions. This study introduces a module design that integrates capabilities in flat-plate PV directly with the most sophisticated CPV technologies, for capture of both direct and diffuse sunlight, thereby achieving efficiency in PV conversion of the global solar radiation. Specific examples of this scheme exploit commodity silicon (Si) cells integrated with two different CPV module designs, where they capture light that is not efficiently directed by the concentrator optics onto large-scale arrays of miniature multijunction (MJ) solar cells that use advanced III-V semiconductor technologies. In this CPV scheme (

  18. Design, Construction And Characterization Of A Pyranometer For Measuring Global Solar Radiation

    Onah, D.U; Osuji, R.O.

    2004-01-01

    Due to cost and stringent importation requirement, we have designed and constructed a Pyranometer from locally available materials. The constructed Pyranometer was calibrated against a standard calibrated Eppley pyranometer model PSP17190F3. the two pyranometers were used simultaneously in measuring global solar radiation at Nsukka, Nigeria on latitude 6.8 degree North and longitude 7.35 degree East, located 488m above sea level. The average insolation for each of the two typical clear sky days were 3.221KW per square metre and 3.266KW per square metre. The maximum insolation obtained with the constructed pyranometer was 965.5 W per square metre on 16/1/03. The corresponding insolation obtained with the reference Eppley pyranometre on the same day was 1087.5W per square metre. We are happy to remark that there was not significant difference between the performances of the constructed pyranometer and the standard Eppley pyranometer

  19. The influence of diffusion and of reabsorption of radiation on the particle and energy balance of an infinitely long quasi-cylindrical discharge in hydrogen gas

    Goedheer, W.J.

    1978-09-01

    A numerical study of the pressure and temperature profiles of an infinitely long quasi-cylindrical discharge in hydrogen gas is presented. In particular the influence of the diffusion of atoms in the ground state and the reabsorption of Lyman-α and Lyman-β radiation on both the particle balance and the energy balance of the discharge is studied. Because the transport of the charged particles is corrected for toroidal effects in the regime of high collisionality which is present in the discharge, the model is quasi-cylindrical. The results obtained show an increase of the neutral density on the axis and of the ion and electron density near the wall of the discharge, as compared with earlier calculations in which both diffusion and reabsorption of radiation were neglected. The results are in agreement with measurements in the 'Ringboog' experiment. (Auth.)

  20. Numerical simulation of surface solar radiation over Southern Africa. Part 1: Evaluation of regional and global climate models

    Tang, Chao; Morel, Béatrice; Wild, Martin; Pohl, Benjamin; Abiodun, Babatunde; Bessafi, Miloud

    2018-02-01

    This study evaluates the performance of climate models in reproducing surface solar radiation (SSR) over Southern Africa (SA) by validating five Regional Climate Models (RCM, including CCLM4, HIRHAM5, RACMO22T, RCA4 and REMO2009) that participated in the Coordinated Regional Downscaling Experiment program over Africa (CORDEX-Africa) along with their ten driving General Circulation Models (GCMs) from the Coupled Model Intercomparison Project Phase 5 over SA. The model simulated SSR was thereby compared to reference data from ground-based measurements, satellite-derived products and reanalyses over the period 1990-2005. Results show that (1) the references obtained from satellite retrievals and reanalyses overall overestimate SSR by up to 10 W/m2 on average when compared to ground-based measurements from the Global Energy Balance Archive, which are located mainly over the eastern part of the southern African continent. (2) Compared to one of the satellite products (Surface Solar Radiation Data Set—Heliosat Edition 2; SARAH-2): GCMs overestimate SSR over SA in terms of their multi-model mean by about 1 W/m2 (compensation of opposite biases over sub-regions) and 7.5 W/m2 in austral summer and winter respectively; RCMs driven by GCMs show in their multimodel mean underestimations of SSR in both seasons with Mean Bias Errors (MBEs) of about - 30 W/m2 in austral summer and about - 14 W/m2 in winter compared to SARAH-2. This multi-model mean low bias is dominated by the simulations of the CCLM4, with negative biases up to - 76 W/m2 in summer and - 32 W/m2 in winter. (3) The discrepancies in the simulated SSR over SA are larger in the RCMs than in the GCMs. (4) In terms of trend during the "brightening" period 1990-2005, both GCMs and RCMs (driven by European Centre for Medium-Range Weather Forecasts Reanalysis ERA-Interim, short as ERAINT and GCMs) simulate an SSR trend of less than 1 W/m2 per decade. However, variations of SSR trend exist among different references data

  1. An artificial neural network ensemble model for estimating global solar radiation from Meteosat satellite images

    Linares-Rodriguez, Alvaro; Ruiz-Arias, José Antonio; Pozo-Vazquez, David; Tovar-Pescador, Joaquin

    2013-01-01

    An optimized artificial neural network ensemble model is built to estimate daily global solar radiation over large areas. The model uses clear-sky estimates and satellite images as input variables. Unlike most studies using satellite imagery based on visible channels, our model also exploits all information within infrared channels of the Meteosat 9 satellite. A genetic algorithm is used to optimize selection of model inputs, for which twelve are selected – eleven 3-km Meteosat 9 channels and one clear-sky term. The model is validated in Andalusia (Spain) from January 2008 through December 2008. Measured data from 83 stations across the region are used, 65 for training and 18 independent ones for testing the model. At the latter stations, the ensemble model yields an overall root mean square error of 6.74% and correlation coefficient of 99%; the generated estimates are relatively accurate and errors spatially uniform. The model yields reliable results even on cloudy days, improving on current models based on satellite imagery. - Highlights: • Daily solar radiation data are generated using an artificial neural network ensemble. • Eleven Meteosat channels observations and a clear sky term are used as model inputs. • Model exploits all information within infrared Meteosat channels. • Measured data for a year from 83 ground stations are used. • The proposed approach has better performance than existing models on daily basis

  2. Estimation of monthly-mean daily global solar radiation based on MODIS and TRMM products

    Qin, Jun; Chen, Zhuoqi; Yang, Kun; Liang, Shunlin; Tang, Wenjun

    2011-01-01

    Global solar radiation (GSR) is required in a large number of fields. Many parameterization schemes are developed to estimate it using routinely measured meteorological variables, since GSR is directly measured at a limited number of stations. Even so, meteorological stations are sparse, especially, in remote areas. Satellite signals (radiance at the top of atmosphere in most cases) can be used to estimate continuous GSR in space. However, many existing remote sensing products have a relatively coarse spatial resolution and these inversion algorithms are too complicated to be mastered by experts in other research fields. In this study, the artificial neural network (ANN) is utilized to build the mathematical relationship between measured monthly-mean daily GSR and several high-level remote sensing products available for the public, including Moderate Resolution Imaging Spectroradiometer (MODIS) monthly averaged land surface temperature (LST), the number of days in which the LST retrieval is performed in 1 month, MODIS enhanced vegetation index, Tropical Rainfall Measuring Mission satellite (TRMM) monthly precipitation. After training, GSR estimates from this ANN are verified against ground measurements at 12 radiation stations. Then, comparisons are performed among three GSR estimates, including the one presented in this study, a surface data-based estimate, and a remote sensing product by Japan Aerospace Exploration Agency (JAXA). Validation results indicate that the ANN-based method presented in this study can estimate monthly-mean daily GSR at a spatial resolution of about 5 km with high accuracy.

  3. Regulation of the oxidative balance with coenzyme Q10 sensitizes human glioblastoma cells to radiation and temozolomide.

    Frontiñán-Rubio, Javier; Santiago-Mora, Raquel María; Nieva-Velasco, Consuelo María; Ferrín, Gustavo; Martínez-González, Alicia; Gómez, María Victoria; Moreno, María; Ariza, Julia; Lozano, Eva; Arjona-Gutiérrez, Jacinto; Gil-Agudo, Antonio; De la Mata, Manuel; Pesic, Milica; Peinado, Juan Ramón; Villalba, José M; Pérez-Romasanta, Luis; Pérez-García, Víctor M; Alcaín, Francisco J; Durán-Prado, Mario

    2018-05-18

    To investigate how the modulation of the oxidative balance affects cytotoxic therapies in glioblastoma, in vitro. Human glioblastoma U251 and T98 cells and normal astrocytes C8D1A were loaded with coenzyme Q10 (CoQ). Mitochondrial superoxide ion (O 2 - ) and H 2 O 2 were measured by fluorescence microscopy. OXPHOS performance was assessed in U251 cells with an oxytherm Clark-type electrode. Radio- and chemotherapy cytotoxicity was assessed by immunostaining of γH2AX (24 h), annexin V and nuclei morphology, at short (72 h) and long (15 d) time. Hif-1α, SOD1, SOD2 and NQO1 were determined by immunolabeling. Catalase activity was measured by classic enzymatic assay. Glutathione levels and total antioxidant capacity were quantified using commercial kits. CoQ did not affect oxygen consumption but reduced the level of O 2 - and H 2 O 2 while shifted to a pro-oxidant cell status mainly due to a decrease in catalase activity and SOD2 level. Hif-1α was dampened, echoed by a decrease lactate and several key metabolites involved in glutathione synthesis. CoQ-treated cells were twofold more sensitive than control to radiation-induced DNA damage and apoptosis in short and long-term clonogenic assays, potentiating TMZ-induced cytotoxicity, without affecting non-transformed astrocytes. CoQ acts as sensitizer for cytotoxic therapies, disarming GBM cells, but not normal astrocytes, against further pro-oxidant injuries, being potentially useful in clinical practice for this fatal pathology. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Design strategies to minimize the radiative efficiency of global warming molecules

    Bera, Partha P.; Francisco, Joseph S.; Lee, Timothy J.

    2010-01-01

    A strategy is devised to screen molecules based on their radiative efficiency. The methodology should be useful as one additional constraint when determining the best molecule to use for an industrial application. The strategy is based on the results of a recent study where we examined molecular properties of global warming molecules using ab initio electronic structure methods to determine which fundamental molecular properties are important in assessing the radiative efficiency of a molecule. Six classes of perfluorinated compounds are investigated. For similar numbers of fluorine atoms, their absorption of radiation in the IR window decreases according to perfluoroethers > perfluorothioethers ≈ sulfur/carbon compounds > perfluorocarbons > perfluoroolefins > carbon/nitrogen compounds. Perfluoroethers and hydrofluorethers are shown to possess a large absorption in the IR window due to (i) the C─O bonds are very polar, (ii) the C-O stretches fall within the IR window and have large IR intensity due to their polarity, and (iii) the IR intensity for C-F stretches in which the fluorine atom is bonded to the carbon that is bonded to the oxygen atom is enhanced due to a larger C─F bond polarity. Lengthening the carbon chain leads to a larger overall absorption in the IR window, though the IR intensity per bond is smaller. Finally, for a class of partially fluorinated compounds with a set number of electronegative atoms, the overall absorption in the IR window can vary significantly, as much as a factor of 2, depending on how the fluorine atoms are distributed within the molecule. PMID:20439762

  5. Global Harmonization of Quality Assurance Naming Conventions in Radiation Therapy Clinical Trials

    Melidis, Christos, E-mail: christos.melidis@eortc.be [European Organization for the Research and Treatment of Cancer–Radiation Oncology Group (EORTC-ROG), Radiation Therapy Quality Assurance (RTQA), Brussels (Belgium); Bosch, Walther R. [Washington University, representing Advanced Technology Consortium, Radiation Oncology, St. Louis, Missouri (United States); Izewska, Joanna [Dosimetry Laboratory, International Atomic Energy Agency, Vienna (Austria); Fidarova, Elena; Zubizarreta, Eduardo [Applied Radiation Biology and Radiotherapy Section, International Atomic Energy Agency, Vienna (Austria); Ulin, Kenneth [Department of Radiation Oncology, University of Massachusetts Medical School, Representing Quality Assurance Review Center, Worcester, Massachusetts (United States); Ishikura, Satoshi [Department of Radiation Oncology, Juntendo University, Representing Japan Clinical Oncology Group, RTQA, Tokyo (Japan); Followill, David [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Representing Radiological Physics Center, RTQA, Houston, Texas (United States); Galvin, James [Department of Radiation Oncology, Thomas Jefferson University, Representing Radiation Therapy Oncology Group, RTQA, Philadelphia, Pennsylvania (United States); Haworth, Annette [Department of Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, representing TransTasman Radiation Oncology Group (TROG) Cancer Research, Newcastle (Australia); Besuijen, Deidre [North West Cancer Centre, Representing TROG Cancer Research, Newcastle (Australia); Clark, Clark H. [Department of Medical Physics, St. Luke' s Cancer Centre, Royal Surrey County Hospital, Guildford, Surrey and National Physical Laboratory, Teddington, Middlesex, representing Radiation Therapy Trials Quality Assurance (RTTQA) (United Kingdom); Miles, Elizabeth; Aird, Edwin [Mount Vernon Cancer Centre, Northwood, Middlesex representing RTTQA (United Kingdom); and others

    2014-12-01

    Purpose: To review the various radiation therapy quality assurance (RTQA) procedures used by the Global Clinical Trials RTQA Harmonization Group (GHG) steering committee members and present the harmonized RTQA naming conventions by amalgamating procedures with similar objectives. Methods and Materials: A survey of the GHG steering committee members' RTQA procedures, their goals, and naming conventions was conducted. The RTQA procedures were classified as baseline, preaccrual, and prospective/retrospective data capture and analysis. After all the procedures were accumulated and described, extensive discussions took place to come to harmonized RTQA procedures and names. Results: The RTQA procedures implemented within a trial by the GHG steering committee members vary in quantity, timing, name, and compliance criteria. The procedures of each member are based on perceived chances of noncompliance, so that the quality of radiation therapy planning and treatment does not negatively influence the trial measured outcomes. A comparison of these procedures demonstrated similarities among the goals of the various methods, but the naming given to each differed. After thorough discussions, the GHG steering committee members amalgamated the 27 RTQA procedures to 10 harmonized ones with corresponding names: facility questionnaire, beam output audit, benchmark case, dummy run, complex treatment dosimetry check, virtual phantom, individual case review, review of patients' treatment records, and protocol compliance and dosimetry site visit. Conclusions: Harmonized RTQA harmonized naming conventions, which can be used in all future clinical trials involving radiation therapy, have been established. Harmonized procedures will facilitate future intergroup trial collaboration and help to ensure comparable RTQA between international trials, which enables meta-analyses and reduces RTQA workload for intergroup studies.

  6. Solar Simulated Ultraviolet Radiation Induces Global Histone Hypoacetylation in Human Keratinocytes.

    Zhang, Xiaoru; Kluz, Thomas; Gesumaria, Lisa; Matsui, Mary S; Costa, Max; Sun, Hong

    2016-01-01

    Ultraviolet radiation (UVR) from sunlight is the primary effector of skin DNA damage. Chromatin remodeling and histone post-translational modification (PTM) are critical factors in repairing DNA damage and maintaining genomic integrity, however, the dynamic changes of histone marks in response to solar UVR are not well characterized. Here we report global changes in histone PTMs induced by solar simulated UVR (ssUVR). A decrease in lysine acetylation of histones H3 and H4, particularly at positions of H3 lysine 9, lysine 56, H4 lysine 5, and lysine 16, was found in human keratinocytes exposed to ssUVR. These acetylation changes were highly associated with ssUVR in a dose-dependent and time-specific manner. Interestingly, H4K16ac, a mark that is crucial for higher order chromatin structure, exhibited a persistent reduction by ssUVR that was transmitted through multiple cell divisions. In addition, the enzymatic activities of histone acetyltransferases were significantly reduced in irradiated cells, which may account for decreased global acetylation. Moreover, depletion of histone deacetylase SIRT1 in keratinocytes rescued ssUVR-induced H4K16 hypoacetylation. These results indicate that ssUVR affects both HDAC and HAT activities, leading to reduced histone acetylation.

  7. Computing diffuse fraction of global horizontal solar radiation: A model comparison.

    Dervishi, Sokol; Mahdavi, Ardeshir

    2012-06-01

    For simulation-based prediction of buildings' energy use or expected gains from building-integrated solar energy systems, information on both direct and diffuse component of solar radiation is necessary. Available measured data are, however, typically restricted to global horizontal irradiance. There have been thus many efforts in the past to develop algorithms for the derivation of the diffuse fraction of solar irradiance. In this context, the present paper compares eight models for estimating diffuse fraction of irradiance based on a database of measured irradiance from Vienna, Austria. These models generally involve mathematical formulations with multiple coefficients whose values are typically valid for a specific location. Subsequent to a first comparison of these eight models, three better performing models were selected for a more detailed analysis. Thereby, the coefficients of the models were modified to account for Vienna data. The results suggest that some models can provide relatively reliable estimations of the diffuse fractions of the global irradiance. The calibration procedure could only slightly improve the models' performance.

  8. Brightening of the global cloud field by nitric acid and the associated radiative forcing

    R. Makkonen

    2012-08-01

    Full Text Available Clouds cool Earth's climate by reflecting 20% of the incoming solar energy, while also trapping part of the outgoing radiation. The effect of human activities on clouds is poorly understood, but the present-day anthropogenic cooling via changes of cloud albedo and lifetime could be of the same order as warming from anthropogenic addition in CO2. Soluble trace gases can increase water condensation to particles, possibly leading to activation of smaller aerosols and more numerous cloud droplets. We have studied the effect of nitric acid on the aerosol indirect effect with the global aerosol-climate model ECHAM5.5-HAM2. Including the nitric acid effect in the model increases cloud droplet number concentrations globally by 7%. The nitric acid contribution to the present-day cloud albedo effect was found to be −0.32 W m−2 and to the total indirect effect −0.46 W m−2. The contribution to the cloud albedo effect is shown to increase to −0.37 W m−2 by the year 2100, if considering only the reductions in available cloud condensation nuclei. Overall, the effect of nitric acid can play a large part in aerosol cooling during the following decades with decreasing SO2 emissions and increasing NOx and greenhouse gases.

  9. Globalization

    Andru?cã Maria Carmen

    2013-01-01

    The field of globalization has highlighted an interdependence implied by a more harmonious understanding determined by the daily interaction between nations through the inducement of peace and the management of streamlining and the effectiveness of the global economy. For the functioning of the globalization, the developing countries that can be helped by the developed ones must be involved. The international community can contribute to the institution of the development environment of the gl...

  10. Global source attribution of sulfate concentration and direct and indirect radiative forcing

    Y. Yang

    2017-07-01

    Full Text Available The global source–receptor relationships of sulfate concentrations, and direct and indirect radiative forcing (DRF and IRF from 16 regions/sectors for years 2010–2014 are examined in this study through utilizing a sulfur source-tagging capability implemented in the Community Earth System Model (CESM with winds nudged to reanalysis data. Sulfate concentrations are mostly contributed by local emissions in regions with high emissions, while over regions with relatively low SO2 emissions, the near-surface sulfate concentrations are primarily attributed to non-local sources from long-range transport. Regional source efficiencies of sulfate concentrations are higher over regions with dry atmospheric conditions and less export, suggesting that lifetime of aerosols, together with regional export, is important in determining regional air quality. The simulated global total sulfate DRF is −0.42 W m−2, with −0.31 W m−2 contributed by anthropogenic sulfate and −0.11 W m−2 contributed by natural sulfate, relative to a state with no sulfur emissions. In the Southern Hemisphere tropics, dimethyl sulfide (DMS contributes 17–84 % to the total DRF. East Asia has the largest contribution of 20–30 % over the Northern Hemisphere mid- and high latitudes. A 20 % perturbation of sulfate and its precursor emissions gives a sulfate incremental IRF of −0.44 W m−2. DMS has the largest contribution, explaining −0.23 W m−2 of the global sulfate incremental IRF. Incremental IRF over regions in the Southern Hemisphere with low background aerosols is more sensitive to emission perturbation than that over the polluted Northern Hemisphere.

  11. Global source attribution of sulfate concentration and direct and indirect radiative forcing

    Yang, Yang; Wang, Hailong; Smith, Steven J.; Easter, Richard; Ma, Po-Lun; Qian, Yun; Yu, Hongbin; Li, Can; Rasch, Philip J.

    2017-07-01

    The global source-receptor relationships of sulfate concentrations, and direct and indirect radiative forcing (DRF and IRF) from 16 regions/sectors for years 2010-2014 are examined in this study through utilizing a sulfur source-tagging capability implemented in the Community Earth System Model (CESM) with winds nudged to reanalysis data. Sulfate concentrations are mostly contributed by local emissions in regions with high emissions, while over regions with relatively low SO2 emissions, the near-surface sulfate concentrations are primarily attributed to non-local sources from long-range transport. Regional source efficiencies of sulfate concentrations are higher over regions with dry atmospheric conditions and less export, suggesting that lifetime of aerosols, together with regional export, is important in determining regional air quality. The simulated global total sulfate DRF is -0.42 W m-2, with -0.31 W m-2 contributed by anthropogenic sulfate and -0.11 W m-2 contributed by natural sulfate, relative to a state with no sulfur emissions. In the Southern Hemisphere tropics, dimethyl sulfide (DMS) contributes 17-84 % to the total DRF. East Asia has the largest contribution of 20-30 % over the Northern Hemisphere mid- and high latitudes. A 20 % perturbation of sulfate and its precursor emissions gives a sulfate incremental IRF of -0.44 W m-2. DMS has the largest contribution, explaining -0.23 W m-2 of the global sulfate incremental IRF. Incremental IRF over regions in the Southern Hemisphere with low background aerosols is more sensitive to emission perturbation than that over the polluted Northern Hemisphere.

  12. Studying the physical basis of global warming: thermal effects of the interaction between radiation and matter and greenhouse effect

    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 frequency, as a result of interaction between matter and radiation. Multiple experiences are suggested to favour a progressive construction of knowledge on the physical aspects necessary to understand the greenhouse effect and global warming. Some results obtained with university students are briefly reported.

  13. Studying the physical basis of global warming: thermal effects of the interaction between radiation and matter and greenhouse effect

    Besson, Ugo; De Ambrosis, Anna; Mascheretti, Paolo [Department of Physics ' A Volta' , University of Pavia, Via A Bassi 6, 27100 Pavia (Italy)], E-mail: ugo.besson@unipv.it, E-mail: anna.deambrosisvigna@unipv.it

    2010-03-15

    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 frequency, as a result of interaction between matter and radiation. Multiple experiences are suggested to favour a progressive construction of knowledge on the physical aspects necessary to understand the greenhouse effect and global warming. Some results obtained with university students are briefly reported.

  14. Global gas balance and influence of atomic hydrogen irradiation on the wall inventory in steady-state operation of QUEST tokamak

    Kuzmin, A., E-mail: kuzmin@triam.kyushu-u.ac.jp [RIAM, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580 (Japan); Zushi, H. [RIAM, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580 (Japan); Takagi, I. [Graduate School of Engineering, Kyoto University (Japan); Sharma, S.K. [Institute for Plasma Research, Ahmadabad, Gujrat (India); Rusinov, A. [RIAM, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580 (Japan); Inoue, Y. [IGSES, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580 (Japan); Hirooka, Y. [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Zhou, H. [Graduate School for Advanced Studies, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Kobayashi, M. [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Sakamoto, M. [Plasma Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 (Japan); Hanada, K.; Yoshida, N.; Nakamura, K.; Fujisawa, A.; Matsuoka, K.; Idei, H.; Nagashima, Y.; Hasegawa, M.; Onchi, T. [RIAM, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580 (Japan); Banerjee, S. [IGSES, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580 (Japan); and others

    2015-08-15

    Hydrogen wall pumping is studied in steady state tokamak operation (SSTO) of QUEST with all metal plasma facing materials PFMs at 100 °C. The duration of SSTO is up to 820 s in fully non-inductive plasma. Global gas balance analysis shows that wall pumping at the apparent (retention–release) rate of 1–6 × 10{sup 18} H/s is dominant and 70–80% of injected H{sub 2} can be retained in PFMs. However, immediately after plasma termination the H{sub 2} release rate enhances to ∼10{sup 19} H/s. In order to understand a true retention process the direct measurement of retention flux has been carried out by permeation probes. The comparison between the evaluated wall retention and results from global analysis is discussed.

  15. Global gas balance and influence of atomic hydrogen irradiation on the wall inventory in steady-state operation of QUEST tokamak

    Kuzmin, A.; Zushi, H.; Takagi, I.; Sharma, S. K.; Rusinov, A.; Inoue, Y.; Hirooka, Y.; Zhou, H.; Kobayashi, M.; Sakamoto, M.; Hanada, K.; Yoshida, N.; Nakamura, K.; Fujisawa, A.; Matsuoka, K.; Idei, H.; Nagashima, Y.; Hasegawa, M.; Onchi, T.; Banerjee, S.; Mishra, K.

    2015-08-01

    Hydrogen wall pumping is studied in steady state tokamak operation (SSTO) of QUEST with all metal plasma facing materials PFMs at 100 °C. The duration of SSTO is up to 820 s in fully non-inductive plasma. Global gas balance analysis shows that wall pumping at the apparent (retention-release) rate of 1-6 × 1018 H/s is dominant and 70-80% of injected H2 can be retained in PFMs. However, immediately after plasma termination the H2 release rate enhances to ∼1019 H/s. In order to understand a true retention process the direct measurement of retention flux has been carried out by permeation probes. The comparison between the evaluated wall retention and results from global analysis is discussed.

  16. Global gas balance and influence of atomic hydrogen irradiation on the wall inventory in steady-state operation of QUEST tokamak

    Kuzmin, A.; Zushi, H.; Takagi, I.; Sharma, S.K.; Rusinov, A.; Inoue, Y.; Hirooka, Y.; Zhou, H.; Kobayashi, M.; Sakamoto, M.; Hanada, K.; Yoshida, N.; Nakamura, K.; Fujisawa, A.; Matsuoka, K.; Idei, H.; Nagashima, Y.; Hasegawa, M.; Onchi, T.; Banerjee, S.

    2015-01-01

    Hydrogen wall pumping is studied in steady state tokamak operation (SSTO) of QUEST with all metal plasma facing materials PFMs at 100 °C. The duration of SSTO is up to 820 s in fully non-inductive plasma. Global gas balance analysis shows that wall pumping at the apparent (retention–release) rate of 1–6 × 10 18 H/s is dominant and 70–80% of injected H 2 can be retained in PFMs. However, immediately after plasma termination the H 2 release rate enhances to ∼10 19 H/s. In order to understand a true retention process the direct measurement of retention flux has been carried out by permeation probes. The comparison between the evaluated wall retention and results from global analysis is discussed

  17. MO-FG-BRB-02: Uniform Access to Radiation Therapy by 2035: Global Task Force on Radiotherapy for Cancer Control

    Jaffray, D.

    2015-01-01

    The global burden of cancer is growing rapidly with an estimated 15 million new cases per year worldwide in 2015, growing to 19 million by 2025 and 24 million by 2035. The largest component of this growth will occur in low-to-middle income countries (LMICs). About half of these cases will require radiation treatment. The gap for available cancer treatment, including radiation therapy, between high-income countries (HICs) and LMICs is enormous. Accurate data and quantitative models to project the needs and the benefits of cancer treatment are a critical first step in closing the large cancer divide between LMICs and HICs. In this context, the Union for International Cancer Control (UICC) has developed a Global Task Force on Radiotherapy for Cancer Control (GTFRCC) with a charge to answer the question as to what it will take to close the gap between what exists today and reasonable access to radiation therapy globally by 2035 and what the potential clinical and economic benefits are for doing this. The Task Force has determined the projections of cancer incidence and the infrastructure required to provide access to radiation therapy globally. Furthermore it has shown that appropriate investment not only yields improved clinical outcomes for millions of patients but that it also provides an overall economic gain throughout all the income settings where this investment is made. This symposium will summarize the facets associated with this global cancer challenge by reviewing the cancer burden, looking at the requirements for radiation therapy, reviewing the benefits of providing such therapy both from a clinical and economic perspective and finally by looking at what approaches can be used to aid in the alleviation of this global cancer challenge. The speakers are world renowned experts in global public health issues (R. Atun), medical physics (D. Jaffray) and radiation oncology (N. Coleman). Learning Objectives: To describe the global cancer challenge and the

  18. MO-FG-BRB-02: Uniform Access to Radiation Therapy by 2035: Global Task Force on Radiotherapy for Cancer Control

    Jaffray, D. [Princess Margaret Cancer Centre (Canada)

    2015-06-15

    The global burden of cancer is growing rapidly with an estimated 15 million new cases per year worldwide in 2015, growing to 19 million by 2025 and 24 million by 2035. The largest component of this growth will occur in low-to-middle income countries (LMICs). About half of these cases will require radiation treatment. The gap for available cancer treatment, including radiation therapy, between high-income countries (HICs) and LMICs is enormous. Accurate data and quantitative models to project the needs and the benefits of cancer treatment are a critical first step in closing the large cancer divide between LMICs and HICs. In this context, the Union for International Cancer Control (UICC) has developed a Global Task Force on Radiotherapy for Cancer Control (GTFRCC) with a charge to answer the question as to what it will take to close the gap between what exists today and reasonable access to radiation therapy globally by 2035 and what the potential clinical and economic benefits are for doing this. The Task Force has determined the projections of cancer incidence and the infrastructure required to provide access to radiation therapy globally. Furthermore it has shown that appropriate investment not only yields improved clinical outcomes for millions of patients but that it also provides an overall economic gain throughout all the income settings where this investment is made. This symposium will summarize the facets associated with this global cancer challenge by reviewing the cancer burden, looking at the requirements for radiation therapy, reviewing the benefits of providing such therapy both from a clinical and economic perspective and finally by looking at what approaches can be used to aid in the alleviation of this global cancer challenge. The speakers are world renowned experts in global public health issues (R. Atun), medical physics (D. Jaffray) and radiation oncology (N. Coleman). Learning Objectives: To describe the global cancer challenge and the

  19. Balance Sheet Network Analysis of Too-Connected-to-Fail Risk in Global and Domestic Banking Systems

    Jorge A Chan-Lau

    2010-01-01

    The 2008/9 financial crisis highlighted the importance of evaluating vulnerabilities owing to interconnectedness, or Too-Connected-to-Fail risk, among financial institutions for country monitoring, financial surveillance, investment analysis and risk management purposes. This paper illustrates the use of balance sheet-based network analysis to evaluate interconnectedness risk, under extreme adverse scenarios, in banking systems in mature and emerging market countries, and between individual b...

  20. Prediction of Daily Global Solar Radiation by Daily Temperatures and Artificial Neural Networks in Different Climates

    S. I Saedi

    2018-03-01

    Full Text Available Introduction Global solar radiation is the sum of direct, diffuse, and reflected solar radiation. Weather forecasts, agricultural practices, and solar equipment development are three major fields that need proper information about solar radiation. Furthermore, sun in regarded as a huge source of renewable and clean energy which can be used in numerous applications to get rid of environmental impacts of non-renewable fossil fuels. Therefore, easy and fast estimation of daily global solar radiation would play an effective role is these affairs. Materials and Methods This study aimed at predicting the daily global solar radiation by means of artificial neural network (ANN method, based on easy-to-gain weather data i.e. daily mean, minimum and maximum temperatures. Having a variety of climates with long-term valid weather data, Washington State, located at the northwestern part of USA was chosen for this purpose. It has a total number of 19 weather stations to cover all the State climates. First, a station with the largest number of valid historical weather data (Lind was chosen to develop, validate, and test different ANN models. Three training algorithms i.e. Levenberg – Marquardt (LM, Scaled Conjugate Gradient (SCG, and Bayesian regularization (BR were tested in one and two hidden layer networks each with up to 20 neurons to derive six best architectures. R, RMSE, MAPE, and scatter plots were considered to evaluate each network in all steps. In order to investigate the generalizability of the best six models, they were tested in other Washington State weather stations. The most accurate and general models was evaluated in an Iran sample weather station which was chosen to be Mashhad. Results and Discussion The variation of MSE for the three training functions in one hidden layer models for Lind station indicated that SCG converged weights and biases in shorter time than LM, and LM did that faster than BR. It means that SCG provided the fastest

  1. Simply obtained global radiation, soil temperature and soil moisture in an alley cropping system in semi-arid Kenya

    Mungai, D.N.; Stigter, C.J.; Coulson, C.L.; Ng'ang'a, J.K.

    2000-01-01

    Global radiation, soil temperature and soil moisture data were obtained from a 4-6 year old Cassia siamea/maize (CM) alley cropping (or hedgerow intercropping) system, at a semi-arid site at Machakos, Kenya, in the late eighties. With the growing need to explore and manage variations in

  2. Modeling of the radiative energy balance within a crop canopy for estimating evapotranspiration: Studies on a row planted soybean canopy

    Nakano, Y.; Hirota, O.

    1990-01-01

    The spatial distribution and density of the leaf area within a crop canopy were used to estimate the radiational environment and evapotranspiration. Morphological measurements were pursued on the soybean stands in the early stage of growth when the two-dimensional foliage distribution pattern existed. The rectangular tube model was used to calculate the light absorption by parallel row of crops both short-wave radiation (direct and diffuse solar radiation, and scattered radiation by plant elements) and long-wave radiation (emanated radiation from the sky, ground and leaves). The simulated profiles are in close agreement with the experimentally measured short-wave and net radiation data. The evapotranspiration of a row was calcuated using a simulated net radiation. The model calculation also agreed well with the evapotranspiration estimated by the Bowen ratio method

  3. 2009 - Global Energy Balance - Intendente Camara - Ipatinga - Minas Gerais - Brazil - plant - Superintendence of Energy and Utilities; Balanco energetico global - 2009 - Usina Intendente Camara - Ipatinga - Minas Gerais - Superintendencia de Energia e Utilidades

    Silveira Junior, Jose Ronaldo; Bastos, Moises Hofer [Usinas Siderurgicas de Minas Gerais S/A (USIMINAS), Ipatinga, MG (Brazil)

    2010-07-01

    The Global Energy Balance of the USIMINAS - Usina Intendente Camara em Ipatinga - Minas Gerais - Brazil, in 2009, is presented with the the main energy consumption indicators of the producer areas. It is highlighted during 2009 as followed: the steel demand retraction decurring from the world wild financial crisis, given as consequence the stop of the blast furnace 1 and 2; dinishing of the production of sinter, pig iron, steel, hot and cold rolled rilled mill; gradual elevation of the production rhythm at the at the plant and energy consumption during the year, motivated by the slow and gradual recovering of the steel marketing.

  4. THE INFLUENCE OF A WEATHERED TRAINING PROGRAM OF 20 WEEKS IN FINE MOTRICITY, GLOBAL MOTRICITY AND BALANCE IN OLDER

    Matheus Henrique de Abreu Araújo

    2016-06-01

    Full Text Available Objective: To evaluate the motor development of active older women, the Open University The Third Aged, ESEFFEGO, Goiânia, GO, before and after the intervention of a resistance exercise program for 20 weeks. Especially the skills of fine motor skills, gross and balance. Methods: The group consisted of 60 elderly with aged 60 and 75 years. To evaluate the group was used EMTI protocol Rosa Neto (2009. Results: The overall motor fitness achieved a significant increase after the interventions, as well as all the surveyed motor skills. Conclusions: interventions were beneficial for the elderly.

  5. The impacts of urban surface characteristics on radiation balance and meteorological variables in the boundary layer around Beijing in summertime

    Liu, Ruiting; Han, Zhiwei; Wu, Jian; Hu, Yonghong; Li, Jiawei

    2017-11-01

    In this study, some key geometric and thermal parameters derived from recent field and satellite observations in Beijing were collected and incorporated into WRF-UCM (Weather Research and Forecasting) model instead of previous default ones. A series of sensitivity model simulations were conducted to investigate the influences of these parameters on radiation balance, meteorological variables, turbulence kinetic energy (TKE), as well as planetary boundary layer height (PBLH) in regions around Beijing in summer 2014. Model validation demonstrated that the updated parameters represented urban surface characteristics more realistically and the simulations of meteorological variables were evidently improved to be closer to observations than the default parameters. The increase in building height tended to increase and slightly decrease surface air temperature at 2 m (T2) at night and around noon, respectively, and to reduce wind speed at 10 m (WS10) through a day. The increase in road width led to significant decreases in T2 and WS10 through the whole day, with the maximum changes in early morning and in evening, respectively. Both lower surface albedo and inclusion of anthropogenic heat (AH) resulted in increases in T2 and WS10 over the day, with stronger influence from AH. The vertical extension of the impact of urban surface parameters was mainly confined within 300 m at night and reached as high as 1600 m during daytime. The increase in building height tended to increase TKE and PBLH and the TKE increase was larger at night than during daytime due to enhancements of both mechanical and buoyant productions. The increase in road width generally reduced TKE and PBLH except for a few hours in the afternoon. The lower surface albedo and the presence of AH consistently resulted in increases of TKE and PBLH through both day and night. The increase in building height induced a slight divergence by day and a notable convergence at night, whereas the increase in road width

  6. Generation of common coefficients to estimate global solar radiation over different locations of India

    Samanta, Suman; Patra, Pulak Kumar; Banerjee, Saon; Narsimhaiah, Lakshmi; Sarath Chandran, M. A.; Vijaya Kumar, P.; Bandyopadhyay, Sanjib

    2018-06-01

    In developing countries like India, global solar radiation (GSR) is measured at very few locations due to non-availability of radiation measuring instruments. To overcome the inadequacy of GSR measurements, scientists developed many empirical models to estimate location-wise GSR. In the present study, three simple forms of Angstrom equation [Angstrom-Prescott (A-P), Ogelman, and Bahel] were used to estimate GSR at six geographically and climatologically different locations across India with an objective to find out a set of common constants usable for whole country. Results showed that GSR values varied from 9.86 to 24.85 MJ m-2 day-1 for different stations. It was also observed that A-P model showed smaller errors than Ogelman and Bahel models. All the models well estimated GSR, as the 1:1 line between measured and estimated values showed Nash-Sutcliffe efficiency (NSE) values ≥ 0.81 for all locations. Measured data of GSR pooled over six selected locations was analyzed to obtain a new set of constants for A-P equation which can be applicable throughout the country. The set of constants (a = 0.29 and b = 0.40) was named as "One India One Constant (OIOC)," and the model was named as "MOIOC." Furthermore, the developed constants are validated statistically for another six locations of India and produce close estimation. High R 2 values (≥ 76%) along with low mean bias error (MBE) ranging from - 0.64 to 0.05 MJ m-2 day-1 revealed that the new constants are able to predict GSR with lesser percentage of error.

  7. Optimization of an artificial neural network dedicated to the multivariate forecasting of daily global radiation

    Voyant, Cyril; Muselli, Marc; Paoli, Christophe; Nivet, Marie-Laure

    2011-01-01

    This paper presents an application of Artificial Neural Networks (ANNs) to predict daily solar radiation. We look at the Multi-Layer Perceptron (MLP) network which is the most used of ANNs architectures. In previous studies, we have developed an ad-hoc time series preprocessing and optimized a MLP with endogenous inputs in order to forecast the solar radiation on a horizontal surface. We propose in this paper to study the contribution of exogenous meteorological data (multivariate method) as time series to our optimized MLP and compare with different forecasting methods: a naive forecaster (persistence), ARIMA reference predictor, an ANN with preprocessing using only endogenous inputs (univariate method) and an ANN with preprocessing using endogenous and exogenous inputs. The use of exogenous data generates an nRMSE decrease between 0.5% and 1% for two stations during 2006 and 2007 (Corsica Island, France). The prediction results are also relevant for the concrete case of a tilted PV wall (1.175 kWp). The addition of endogenous and exogenous data allows a 1% decrease of the nRMSE over a 6 months-cloudy period for the power production. While the use of exogenous data shows an interest in winter, endogenous data as inputs on a preprocessed ANN seem sufficient in summer. -- Research highlights: → Use of exogenous data as ANN inputs to forecast horizontal daily global irradiation data. → New methodology allowing to choice the adequate exogenous data - a systematic method comparing endogenous and exogenous data. → Different referenced mathematical predictors allows to conclude about the pertinence of the proposed methodology.

  8. Concentrator photovoltaic module architectures with capabilities for capture and conversion of full global solar radiation

    Lee, Kyu-Tae; Yao, Yuan; He, Junwen; Fisher, Brent; Sheng, Xing; Lumb, Matthew; Xu, Lu; Anderson, Mikayla A.; Scheiman, David; Han, Seungyong; Kang, Yongseon; Gumus, Abdurrahman; Bahabry, Rabab R.; Lee, Jung Woo; Paik, Ungyu; Bronstein, Noah D.; Alivisatos, A. Paul; Meitl, Matthew; Burroughs, Scott; Mustafa Hussain, Muhammad; Lee, Jeong Chul; Nuzzo, Ralph G.; Rogers, John A.

    2016-12-01

    Emerging classes of concentrator photovoltaic (CPV) modules reach efficiencies that are far greater than those of even the highest performance flat-plate PV technologies, with architectures that have the potential to provide the lowest cost of energy in locations with high direct normal irradiance (DNI). A disadvantage is their inability to effectively use diffuse sunlight, thereby constraining widespread geographic deployment and limiting performance even under the most favorable DNI conditions. This study introduces a module design that integrates capabilities in flat-plate PV directly with the most sophisticated CPV technologies, for capture of both direct and diffuse sunlight, thereby achieving efficiency in PV conversion of the global solar radiation. Specific examples of this scheme exploit commodity silicon (Si) cells integrated with two different CPV module designs, where they capture light that is not efficiently directed by the concentrator optics onto large-scale arrays of miniature multijunction (MJ) solar cells that use advanced III-V semiconductor technologies. In this CPV+ scheme (“+” denotes the addition of diffuse collector), the Si and MJ cells operate independently on indirect and direct solar radiation, respectively. On-sun experimental studies of CPV+ modules at latitudes of 35.9886° N (Durham, NC), 40.1125° N (Bondville, IL), and 38.9072° N (Washington, DC) show improvements in absolute module efficiencies of between 1.02% and 8.45% over values obtained using otherwise similar CPV modules, depending on weather conditions. These concepts have the potential to expand the geographic reach and improve the cost-effectiveness of the highest efficiency forms of PV power generation.

  9. Evaluation of Various Methods for Estimating Global Solar Radiation in the Southeastern United States

    Woli, Prem; Paz, Joel O.

    2012-05-01

    Global solar radiation Rg is an important input for crop models to simulate crop responses. Because the scarcity of long and continuous records of Rg is a serious limitation in many countries, Rg is estimated using models. For crop-model application, empirical Rg models that use commonly measured meteorological variables, such as temperature and precipitation, are generally preferred. Although a large number of models of this kind exist, few have been evaluated for conditions in the United States. This study evaluated the performances of 16 empirical, temperature- and/or precipitation-based Rg models for the southeastern United States. By taking into account spatial distribution and data availability, 30 locations in the region were selected and their daily weather data spanning eight years obtained. One-half of the data was used for calibrating the models, and the other half was used for evaluation. For each model, location-specific parameter values were estimated through regressions. Models were evaluated for each location using the root-mean-square error and the modeling efficiency as goodness-of-fit measures. Among the models that use temperature or precipitation as the input variable, the Mavromatis model showed the best performance. The piecewise linear regression based Wu et al. model (WP) performed best not only among the models that use both temperature and precipitation but also among the 16 models evaluated, mainly because it has separate relationships for low and high radiation levels. The modeling efficiency of WP was from ~5% to more than 100% greater than those of the other models, depending on models and locations.

  10. Estimating Net Primary Productivity Beneath Snowpack Using Snowpack Radiative Transfer Modeling and Global Satellite Data

    Barber, D. E.; Peterson, M. C.

    2002-05-01

    Sufficient photosynthetically active radiation (PAR) penetrates snow for plants to grow beneath snowpack during late winter or early spring in tundra ecosystems. During the spring in this ecosystem, the snowpack creates an environment with higher humidity and less variable and milder temperatures than on the snow-free land. Under these conditions, the amount of PAR available is likely to be the limiting factor for plant growth. Current methods for determining net primary productivity (NPP) of tundra ecosystems do not account for this plant growth beneath snowpack, apparently resulting in underestimating plant production there. We are currently in the process of estimating the magnitude of this early growth beneath snow for tundra ecosystems. Our method includes a radiative transfer model that simulates diffuse and direct PAR penetrating snowpack based on downwelling PAR values and snow depth data from global satellite databases. These PAR levels are convolved with plant growth for vegetation that thrives beneath snowpacks, such as lichen. We expect to present the net primary production for Cladonia species (a common Arctic lichen) that has the capability of photosynthesizing at low temperatures beneath snowpack. This method may also be used to study photosynthesis beneath snowpacks in other hardy plants. Lichens are used here as they are common in snow-covered regions, flourish under snowpack, and provide an important food source for tundra herbivores (e.g. caribou). In addition, lichens are common in arctic-alpine environments and our results can be applied to these ecosystems as well. Finally, the NPP of lichen beneath snowpack is relatively well understood compared to other plants, making it ideal vegetation for this first effort at estimating the potential importance of photosynthesis at large scales. We are examining other candidate plants for their photosynthetic potential beneath snowpack at this time; however, little research has been done on this topic. We

  11. Is China turning Latin? : China’s balancing act between power and dependence on the wave of global imbalances

    A.M. Fischer (Andrew Martín)

    2010-01-01

    textabstractThis paper investigates whether China has escaped the vulnerabilities of peripheral and dependent late industrialisation in the build up to the current global economic crisis, with reference to structuralist critiques of Latin American industrialisation in the 1960s and examined

  12. Global direct radiative forcing by process-parameterized aerosol optical properties

    KirkevâG, Alf; Iversen, Trond

    2002-10-01

    A parameterization of aerosol optical parameters is developed and implemented in an extended version of the community climate model version 3.2 (CCM3) of the U.S. National Center for Atmospheric Research. Direct radiative forcing (DRF) by monthly averaged calculated concentrations of non-sea-salt sulfate and black carbon (BC) is estimated. Inputs are production-specific BC and sulfate from [2002] and background aerosol size distribution and composition. The scheme interpolates between tabulated values to obtain the aerosol single scattering albedo, asymmetry factor, extinction coefficient, and specific extinction coefficient. The tables are constructed by full calculations of optical properties for an array of aerosol input values, for which size-distributed aerosol properties are estimated from theory for condensation and Brownian coagulation, assumed distribution of cloud-droplet residuals from aqueous phase oxidation, and prescribed properties of the background aerosols. Humidity swelling is estimated from the Köhler equation, and Mie calculations finally yield spectrally resolved aerosol optical parameters for 13 solar bands. The scheme is shown to give excellent agreement with nonparameterized DRF calculations for a wide range of situations. Using IPCC emission scenarios for the years 2000 and 2100, calculations with an atmospheric global cliamte model (AFCM) yield a global net anthropogenic DRF of -0.11 and 0.11 W m-2, respectively, when 90% of BC from biomass burning is assumed anthropogenic. In the 2000 scenario, the individual DRF due to sulfate and BC has separately been estimated to -0.29 and 0.19 W m-2, respectively. Our estimates of DRF by BC per BC mass burden are lower than earlier published estimates. Some sensitivity tests are included to investigate to what extent uncertain assumptions may influence these results.

  13. Campbell-Bristow development Model for Estimating Global Solar radiation in the Region of Junin, Perú

    Dr. Becquer Frauberth Camayo-Lapa

    2015-11-01

    Full Text Available In order to have a tool to estimate the monthly and annual solar radiation on the horizontal surface in Junín region, in which is not available with this information, adapted Bristow-Campbell (1984 model for estimating global solar radiation monthly average.   To develop the model of Bristow-Campbell that estimates the average daily global solar radiation monthly modeling technique proposed by Espinoza (2010, were recorded daily maximum and minimum temperatures of 19 weather stations and the equations proposed  by the Solar High Peru 2003 was adapted to this model.  The Bristow-Campbell model was developed with data recorded in stations: Santa Ana, Tarma and Satipo belonging to Sierra and Selva, respectively. The performance of applications calculated solar radiation was determined by considering the OLADE (1992 that solar radiation over 4,0 kWh/m2/day are profitable and 5,0 kWh/m2/day very profitable. The results indicate that the monthly average global solar radiation in Junín  region is 5,3  kWh/m2/day corresponding to the  4,2 Forest and the Sierra 5,6 kWh/m2/day kWh/m2/day. Profitability is determined for the less profitable Selva and Sierra is very profitable. In addition, the operating model is simple and available to all users. We conclude that application of the Bristow-Campbell model adapted, it is an instrument of great utility to generate a comprehensive database of available solar radiation in Junín region.

  14. Methods and strategy for modeling daily global solar radiation with measured meteorological data - A case study in Nanchang station, China

    Wu, Guofeng; Liu, Yaolin; Wang, Tiejun

    2007-01-01

    Solar radiation is a primary driver for many physical, chemical and biological processes on the earth's surface, and complete and accurate solar radiation data at a specific region are quite indispensable to the solar energy related researches. This study, with Nanchang station, China, as a case study, aimed to calibrate existing models and develop new models for estimating missing global solar radiation data using commonly measured meteorological data and to propose a strategy for selecting the optimal models under different situations of available meteorological data. Using daily global radiation, sunshine hours, temperature, total precipitation and dew point data covering the years from 1994 to 2005, we calibrated or developed and evaluated seven existing models and two new models. Validation criteria included intercept, slope, coefficient of determination, mean bias error and root mean square error. The best result (R 2 = 0.93) was derived from Chen model 2, which uses sunshine hours and temperature as predictors. The Bahel model, which only uses sunshine hours, was almost as good, explaining 92% of the solar radiation variance. Temperature based models (Bristow and Campbell, Allen, Hargreaves and Chen 1 models) provided less accurate results, of which the best one (R 2 = 0.69) is the Bristow and Campbell model. The temperature based models were improved by adding other variables (daily mean total precipitation and mean dew point). Two such models could explain 77% (Wu model 1) and 80% (Wu model 2) of the solar radiation variance. We, thus, propose a strategy for selecting an optimal method for calculating missing daily values of global solar radiation: (1) when sunshine hour and temperature data are available, use Chen model 2; (2) when only sunshine hour data are available, use Bahel model; (3) when temperature, total precipitation and dew point data are available but not sunshine hours, use Wu model 2; (4) when only temperature and total precipitation are

  15. Vertical Distribution of Radiation and Energy Balance Partitioning Within and Above a Lodgepole Pine Stand Recovering from a Recent Insect Attack

    Emmel, Carmen; Paul-Limoges, Eugenie; Black, Thomas Andrew; Christen, Andreas

    2013-11-01

    The current outbreak of mountain pine beetle (MPB) that started in the late 1990s in British Columbia, Canada, is the largest ever recorded in the north American native habitat of the beetle. The killing of trees is expected to change the vertical distribution of net radiation () and the partitioning of latent () and sensible () heat fluxes in the different layers of an attacked forest canopy. During an intensive observation period in the summer of 2010, eddy-covariance flux and radiation measurements were made at seven heights from ground level up to 1.34 times the canopy height in an MPB-attacked open-canopy forest stand in the interior of British Columbia, Canada. The lodgepole pine dominated stand with a rich secondary structure (trees and understorey not killed by the beetle) was first attacked by the MPB in 2003 and received no management. In this study, the vertical distribution of the energy balance components and their sources and sinks were analyzed and energy balance closure (EBC) was determined for various levels within the canopy. The low stand density resulted in approximately 60 % of the shortwave irradiance and 50 % of the daily total reaching the ground. Flux divergence calculations indicated relatively strong sources of latent heat at the ground and where the secondary structure was located. Only very weak sources of latent heat were found in the upper part of the canopy, which was mainly occupied by dead lodgepole pine trees. was the dominant term throughout the canopy, and the Bowen ratio () increased with height in the canopy. Soil heat flux () accounted for approximately 4 % of . Sensible heat storage in the air () was the largest of the energy balance storage components in the upper canopy during daytime, while in the lower canopy sensible heat storage in the boles () and biochemical energy storage () were the largest terms. was almost constant from the bottom to above the canopy. , and latent heat storage in the air () varied more than

  16. Support vector regression methodology for estimating global solar radiation in Algeria

    Guermoui, Mawloud; Rabehi, Abdelaziz; Gairaa, Kacem; Benkaciali, Said

    2018-01-01

    Accurate estimation of Daily Global Solar Radiation (DGSR) has been a major goal for solar energy applications. In this paper we show the possibility of developing a simple model based on the Support Vector Regression (SVM-R), which could be used to estimate DGSR on the horizontal surface in Algeria based only on sunshine ratio as input. The SVM model has been developed and tested using a data set recorded over three years (2005-2007). The data was collected at the Applied Research Unit for Renewable Energies (URAER) in Ghardaïa city. The data collected between 2005-2006 are used to train the model while the 2007 data are used to test the performance of the selected model. The measured and the estimated values of DGSR were compared during the testing phase statistically using the Root Mean Square Error (RMSE), Relative Square Error (rRMSE), and correlation coefficient (r2), which amount to 1.59(MJ/m2), 8.46 and 97,4%, respectively. The obtained results show that the SVM-R is highly qualified for DGSR estimation using only sunshine ratio.

  17. A simple and efficient algorithm to estimate daily global solar radiation from geostationary satellite data

    Lu, Ning; Qin, Jun; Yang, Kun; Sun, Jiulin

    2011-01-01

    Surface global solar radiation (GSR) is the primary renewable energy in nature. Geostationary satellite data are used to map GSR in many inversion algorithms in which ground GSR measurements merely serve to validate the satellite retrievals. In this study, a simple algorithm with artificial neural network (ANN) modeling is proposed to explore the non-linear physical relationship between ground daily GSR measurements and Multi-functional Transport Satellite (MTSAT) all-channel observations in an effort to fully exploit information contained in both data sets. Singular value decomposition is implemented to extract the principal signals from satellite data and a novel method is applied to enhance ANN performance at high altitude. A three-layer feed-forward ANN model is trained with one year of daily GSR measurements at ten ground sites. This trained ANN is then used to map continuous daily GSR for two years, and its performance is validated at all 83 ground sites in China. The evaluation result demonstrates that this algorithm can quickly and efficiently build the ANN model that estimates daily GSR from geostationary satellite data with good accuracy in both space and time. -- Highlights: → A simple and efficient algorithm to estimate GSR from geostationary satellite data. → ANN model fully exploits both the information from satellite and ground measurements. → Good performance of the ANN model is comparable to that of the classical models. → Surface elevation and infrared information enhance GSR inversion.

  18. Estimation of Radiative Efficiency of Chemicals with Potentially Significant Global Warming Potential.

    Betowski, Don; Bevington, Charles; Allison, Thomas C

    2016-01-19

    Halogenated chemical substances are used in a broad array of applications, and new chemical substances are continually being developed and introduced into commerce. While recent research has considerably increased our understanding of the global warming potentials (GWPs) of multiple individual chemical substances, this research inevitably lags behind the development of new chemical substances. There are currently over 200 substances known to have high GWP. Evaluation of schemes to estimate radiative efficiency (RE) based on computational chemistry are useful where no measured IR spectrum is available. This study assesses the reliability of values of RE calculated using computational chemistry techniques for 235 chemical substances against the best available values. Computed vibrational frequency data is used to estimate RE values using several Pinnock-type models, and reasonable agreement with reported values is found. Significant improvement is obtained through scaling of both vibrational frequencies and intensities. The effect of varying the computational method and basis set used to calculate the frequency data is discussed. It is found that the vibrational intensities have a strong dependence on basis set and are largely responsible for differences in computed RE values.

  19. ENVIRONMENTAL-BALANCED SCORECARD DAN ETIKA BISNIS ISLÂM (Suatu Sintesis Manajemen Strategi dalam Persaingan Global

    Rudy Haryanto Rudy Haryanto

    2013-08-01

    Full Text Available Abstract: Business activity is an integral part of economic discourse. Islamic economy system starts from ethical awareness. For its viability, a company runs an old fashioned-management, it is a material-prosperity attainmnet oriented. However, it results a social contradiction. In Islamic ethic, a business must combine material and moral indicators emphesizing profit and expediency harmonies. Islamic business must be on the basis of natural and human resources that is moved by a motivation of dynamic devotion. Thus, it is  significant to have a management strategy that are religious, morality, and humanity oriented. Furthermore, the paradigm change that company goal maintaining the financial aspect change into social and environmental aspects is certain.   Key Words: Manajemen srategis, etika, perusahaan, lingkungan, dan Balanced Scorecard

  20. Daily global solar radiation modelling using multi-layer perceptron neural networks in semi-arid region

    Mawloud GUERMOUI

    2016-07-01

    Full Text Available Accurate estimation of Daily Global Solar Radiation (DGSR has been a major goal for solar energy application. However, solar radiation measurements are not a simple task for several reasons. In the cases where data are not available, it is very common the use of computational models to estimate the missing data, which are based mainly of the search for relationships between weather variables, such as temperature, humidity, sunshine duration, etc. In this respect, the present study focuses on the development of artificial neural network (ANN model for estimation of daily global solar radiation on horizontal surface in Ghardaia city (South Algeria. In this analysis back-propagation algorithm is applied. Daily mean air temperature, relative humidity and sunshine duration was used as climatic inputs parameters, while the daily global solar radiation (DGSR was the only output of the ANN. We have evaluated Multi-Layer Perceptron (MLP models to estimate DGSR using three year of measurement (2005-2008. It was found that MLP-model based on sunshine duration and mean air temperature give accurate results in term of Mean Absolute Bias Error, Root Mean Square Error, Relative Square Error and Correlation Coefficient. The obtained values of these indicators are 0.67 MJ/m², 1.28 MJ/m², 6.12%and 98.18%, respectively which shows that MLP is highly qualified for DGSR estimation in semi-arid climates.

  1. Globalization

    Plum, Maja

    Globalization is often referred to as external to education - a state of affair facing the modern curriculum with numerous challenges. In this paper it is examined as internal to curriculum; analysed as a problematization in a Foucaultian sense. That is, as a complex of attentions, worries, ways...... of reasoning, producing curricular variables. The analysis is made through an example of early childhood curriculum in Danish Pre-school, and the way the curricular variable of the pre-school child comes into being through globalization as a problematization, carried forth by the comparative practices of PISA...

  2. Globalization

    F. Gerard Adams

    2008-01-01

    The rapid globalization of the world economy is causing fundamental changes in patterns of trade and finance. Some economists have argued that globalization has arrived and that the world is “flat†. While the geographic scope of markets has increased, the author argues that new patterns of trade and finance are a result of the discrepancies between “old†countries and “new†. As the differences are gradually wiped out, particularly if knowledge and technology spread worldwide, the t...

  3. The assessment of four different correction models applied to the diffuse radiation measured with a shadow ring using global and normal beam radiation measurements for Beer Sheva, Israel

    Kudish, Avraham I.; Evseev, Efim G. [Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, E D Bergmann Campus, Beer Sheva 84105 (Israel)

    2008-02-15

    The measurement of the diffuse radiation incident on a horizontal surface, a priori a straightforward task, is fraught with difficulties. It is possible to measure the diffuse radiation by three different techniques: two of which measure it directly and the third indirectly. The most accurate is the indirect one, which is based upon the concurrent measurements of the horizontal global and the normal incidence beam radiation. The disadvantage of this being the relatively expensive tracking system required for measuring the latter. The diffuse radiation can be measured directly with a pyranometer outfitted with either an occulting disk or shadow ring, which prevent the beam radiation from impinging on the pyranometer sensor. The occulting disk can provide accurate measurements of the diffuse radiation but it requires a relatively expensive sun tracking system in the east-west axis. The shadow ring is a stationary device with regard to the east-west axis and blocks the beam radiation component by creating a permanent shadow on the pyranometer sensor. The major disadvantage of the shadow ring is that it also blocks that portion of the diffuse radiation obscured by the shadow ring. This introduces a measurement error that must be corrected to account for that portion of the sky obscured by the shadow band. In addition to this geometric correction factor there is a need to correct for anisotropic sky conditions. Four correction models have been applied to the data for Beer Sheva, Israel and the results have been evaluated both graphically and statistically. An attempt has been made to score the relative performance of the models under different sky conditions. (author)

  4. Correlations during the day of diffuse solar radiation to the global solar radiation in Vigo (Spain); Correlaciones minutarias, horarias y diarias de la radiacion solar difusa a la radiacion solar global en Vigo

    Vazquez, M.; Santos, J.

    2004-07-01

    In the Solar Energy Lab of the University of Vigo a weather station has been in operation since October 2001. Two Kipp and Zonen pyranometers, one of them with a shade ring, have been measuring global and diffuse solar radiation. From these data of the years 2002 and 2003, the diffuse-to-global minute, hourly and daily correlations are obtained and shown in graphs. These correlations are also plotted together with other correlations referred in the literature for comparison. The graphs show the effect of the clear-cloudy behaviour of the solar radiation for short periods of time, effect that is not seen for larger periods of time as daily periods. (Author)

  5. Hawking Radiation from Horizons of Reissner-Nordstroem de Sitter Black Hole with a Global Monopole via Anomalies

    Chen Shiwu; Liu Xiongwei; Lin Kai; Zeng Xiaoxiong; Yang Shuzheng

    2008-01-01

    Hawking radiation from cosmological horizon and event horizon of the Reissner-Nordstroem de Sitter black hole with a global monopole is studied via a new method that was propounded by Robinson and Wilzek and elaborated by Banerjee and Kulkarni. The results show that the gauge current and energy-momentum tensor fluxes, which required keeping gauge covariance and general coordinate invariance at the quantum level in the effective field theory, are exactly equivalent to those of Hawking radiation from the event horizon and the cosmological horizon, respectively

  6. "Developing culturally sensitive affect scales for global mental health research and practice: Emotional balance, not named syndromes, in Indian Adivasi subjective well-being".

    Snodgrass, Jeffrey G; Lacy, Michael G; Upadhyay, Chakrapani

    2017-08-01

    We present a perspective to analyze mental health without either a) imposing Western illness categories or b) adopting local or "native" categories of mental distress. Our approach takes as axiomatic only that locals within any culture share a cognitive and verbal lexicon of salient positive and negative emotional experiences, which an appropriate and repeatable set of ethnographic procedures can elicit. Our approach is provisionally agnostic with respect to either Western or native nosological categories, and instead focuses on persons' relative frequency of experiencing emotions. Putting this perspective into practice in India, our ethnographic fieldwork (2006-2014) and survey analysis (N = 219) resulted in a 40-item Positive and Negative Affect Scale (PANAS), which we used to assess the mental well-being of Indigenous persons (the tribal Sahariya) in the Indian states of Rajasthan and Madhya Pradesh. Generated via standard cognitive anthropological procedures that can be replicated elsewhere, measures such as this possess features of psychiatric scales favored by leaders in global mental health initiatives. Though not capturing locally named distress syndromes, our scale is nonetheless sensitive to local emotional experiences, frames of meaning, and "idioms of distress." By sharing traits of both global and also locally-derived diagnoses, approaches like ours can help identify synergies between them. For example, employing data reduction techniques such as factor analysis-where diagnostic and screening categories emerge inductively ex post facto from emotional symptom clusters, rather than being deduced or assigned a priori by either global mental health experts or locals themselves-reveals hidden overlaps between local wellness idioms and global ones. Practically speaking, our perspective, which assesses both emotional frailty and also potential sources of emotional resilience and balance, while eschewing all named illness categories, can be deployed in

  7. Medical exposure assessment: the global approach of the United Nations Scientific Committee on the Effects of Atomic Radiation

    Shannoun, F.

    2015-01-01

    The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) was established in 1955 to systematically collect, evaluate, publish and share data on the global levels and effects of ionizing radiation from natural and artificial sources. Regular surveys have been conducted to determinate the frequencies of medical radiological procedure, the number of equipment and staffing and the level of global exposure using the health care level (HCL) extrapolation model. UNSCEAR surveys revealed a range of issues relating to participation, survey process, data quality and analysis. Thus, UNSCEAR developed an improvement strategy to address the existing deficiencies in data quality and collection. The major element of this strategy is the introduction of an on-line platform to facilitate the data collection and archiving process. It is anticipated that the number of countries participating in UNSCEAR's surveys will increase in the future, particularly from HCL II -IV countries. (authors)

  8. Analysis of Global Horizontal Irradiance in Version 3 of the National Solar Radiation Database.

    Hansen, Clifford; Martin, Curtis E.; Guay, Nathan Gene

    2015-09-01

    We report an analysis that compares global horizontal irradiance (GHI) estimates from version 3 of the National Solar Radiation Database (NSRDB v3) with surface measurements of GHI at a wide variety of locations over the period spanning from 2005 to 2012. The NSRDB v3 estimate of GHI are derived from the Physical Solar Model (PSM) which employs physics-based models to estimate GHI from measurements of reflected visible and infrared irradiance collected by Geostationary Operational Environment Satellites (GOES) and several other data sources. Because the ground measurements themselves are uncertain our analysis does not establish the absolute accuracy for PSM GHI. However by examining the comparison for trends and for consistency across a large number of sites, we may establish a level of confidence in PSM GHI and identify conditions which indicate opportunities to improve PSM. We focus our evaluation on annual and monthly insolation because these quantities directly relate to prediction of energy production from solar power systems. We find that generally, PSM GHI exhibits a bias towards overestimating insolation, on the order of 5% when all sky conditions are considered, and somewhat less (-3%) when only clear sky conditions are considered. The biases persist across multiple years and are evident at many locations. In our opinion the bias originates with PSM and we view as less credible that the bias stems from calibration drift or soiling of ground instruments. We observe that PSM GHI may significantly underestimate monthly insolation in locations subject to broad snow cover. We found examples of days where PSM GHI apparently misidentified snow cover as clouds, resulting in significant underestimates of GHI during these days and hence leading to substantial understatement of monthly insolation. Analysis of PSM GHI in adjacent pixels shows that the level of agreement between PSM GHI and ground data can vary substantially over distances on the order of 2 km. We

  9. Radiation

    2013-01-01

    The chapter one presents the composition of matter and atomic theory; matter structure; transitions; origin of radiation; radioactivity; nuclear radiation; interactions in decay processes; radiation produced by the interaction of radiation with matter

  10. Ecological ethics in captivity: balancing values and responsibilities in zoo and aquarium research under rapid global change.

    Minteer, Ben A; Collins, James P

    2013-01-01

    Ethical obligations to animals in conservation research and management are manifold and often conflicting. Animal welfare concerns often clash with the ethical imperative to understand and conserve a population or ecosystem through research and management intervention. The accelerating pace and impact of global environmental change, especially climate change, complicates our understanding of these obligations. One example is the blurring of the distinction between ex situ (zoo- and aquarium-based) conservation and in situ (field-based) approaches as zoos and aquariums become more active in field conservation work and as researchers and managers consider more intensive interventions in wild populations and ecosystems to meet key conservation goals. These shifts, in turn, have consequences for our traditional understanding of the ethics of wildlife research and management, including our relative weighting of animal welfare and conservation commitments across rapidly evolving ex situ and in situ contexts. Although this changing landscape in many ways supports the increased use of captive wildlife in conservation-relevant research, it raises significant ethical concerns about human intervention in populations and ecosystems, including the proper role of zoos and aquariums as centers for animal research and conservation in the coming decades. Working through these concerns requires a pragmatic approach to ethical analysis, one that is able to make trade-offs among the many goods at stake (e.g., animal welfare, species viability, and ecological integrity) as we strive to protect species from further decline and extinction in this century.

  11. Importance of the green color, absorption gradient, and spectral absorption of chloroplasts for the radiative energy balance of leaves.

    Kume, Atsushi

    2017-05-01

    Terrestrial green plants absorb photosynthetically active radiation (PAR; 400-700 nm) but do not absorb photons evenly across the PAR waveband. The spectral absorbance of photosystems and chloroplasts is lowest for green light, which occurs within the highest irradiance waveband of direct solar radiation. We demonstrate a close relationship between this phenomenon and the safe and efficient utilization of direct solar radiation in simple biophysiological models. The effects of spectral absorptance on the photon and irradiance absorption processes are evaluated using the spectra of direct and diffuse solar radiation. The radiation absorption of a leaf arises as a consequence of the absorption of chloroplasts. The photon absorption of chloroplasts is strongly dependent on the distribution of pigment concentrations and their absorbance spectra. While chloroplast movements in response to light are important mechanisms controlling PAR absorption, they are not effective for green light because chloroplasts have the lowest spectral absorptance in the waveband. With the development of palisade tissue, the incident photons per total palisade cell surface area and the absorbed photons per chloroplast decrease. The spectral absorbance of carotenoids is effective in eliminating shortwave PAR (solar radiation. However, most of the near infrared radiation is unabsorbed and heat stress is greatly reduced. The incident solar radiation is too strong to be utilized for photosynthesis under the current CO 2 concentration in the terrestrial environment. Therefore, the photon absorption of a whole leaf is efficiently regulated by photosynthetic pigments with low spectral absorptance in the highest irradiance waveband and through a combination of pigment density distribution and leaf anatomical structures.

  12. Generation of global hourly radiation sequences using a Transition Markov matrix for Madrid. Generacion de secuencias horarias de radiacion global utilizando matrices de transicion de Markov, para la localidad de Madrid

    Mora, Ll

    1989-11-01

    The aim of this work is the generation of sequences of hourly global radiation which have similar statistically characteristics of real sequences for the city of Madrid (Spain). For this generation, a first order Markov model has been proposed. The input parameters of simulation method are the following: The maximum value of hourly radiation and the average monthly value of the transparency normalized index. The maximum value of hourly radiation has been calculated as a function of the solar height by an empirical expression. The transparency normalized index has been defined as the ratio among the measured hourly global radiation to the maximum value for the corresponding solar height. The method is based on the following observations: -The transparency normalized index shows a significant correlation only for two consecutive hours. -The months with the same average transparency normalized indies have similar probability density function. Global solar radiation, time series, simulation, Markov transition matrix, solar energy.

  13. Energy balance and stability

    Hammer, R.

    1982-01-01

    The energy balance of the outer atmospheres of solarlike stars is discussed. The energy balance of open coronal regions is considered, discussing the construction and characteristics of models of such regions in some detail. In particular, the temperature as a function of height is considered, as are the damping length dependence of the global energy balance in the region between the base of the transition region and the critical point, and the effects of changing the amount of coronal heating, the stellar mass, and the stellar radius. Models of coronal loops are more briefly discussed. The chromosphere is then included in the discussion of the energy balance, and the connection between global energy balance and global thermal stability is addressed. The observed positive correlations between the chromospheric and coronal energy losses and the pressure of the transition region is qualitatively explained

  14. The CarbonTracker Data Assimilation Shell (CTDAS) v1.0: implementation and global carbon balance 2001-2015

    van der Laan-Luijkx, Ingrid T.; van der Velde, Ivar R.; van der Veen, Emma; Tsuruta, Aki; Stanislawska, Karolina; Babenhauserheide, Arne; Zhang, Hui Fang; Liu, Yu; He, Wei; Chen, Huilin; Masarie, Kenneth A.; Krol, Maarten C.; Peters, Wouter

    2017-07-01

    Data assimilation systems are used increasingly to constrain the budgets of reactive and long-lived gases measured in the atmosphere. Each trace gas has its own lifetime, dominant sources and sinks, and observational network (from flask sampling and in situ measurements to space-based remote sensing) and therefore comes with its own optimal configuration of the data assimilation. The CarbonTracker Europe data assimilation system for CO2 estimates global carbon sources and sinks, and updates are released annually and used in carbon cycle studies. CarbonTracker Europe simulations are performed using the new modular implementation of the data assimilation system: the CarbonTracker Data Assimilation Shell (CTDAS). Here, we present and document this redesign of the data assimilation code that forms the heart of CarbonTracker, specifically meant to enable easy extension and modification of the data assimilation system. This paper also presents the setup of the latest version of CarbonTracker Europe (CTE2016), including the use of the gridded state vector, and shows the resulting carbon flux estimates. We present the distribution of the carbon sinks over the hemispheres and between the land biosphere and the oceans. We show that with equal fossil fuel emissions, 2015 has a higher atmospheric CO2 growth rate compared to 2014, due to reduced net land carbon uptake in later year. The European carbon sink is especially present in the forests, and the average net uptake over 2001-2015 was 0. 17 ± 0. 11 PgC yr-1 with reductions to zero during drought years. Finally, we also demonstrate the versatility of CTDAS by presenting an overview of the wide range of applications for which it has been used so far.

  15. Modeling the relationship between photosynthetically active radiation and global horizontal irradiance using singular spectrum analysis

    Zempila, Melina-Maria; Taylor, Michael; Bais, Alkiviadis; Kazadzis, Stelios

    2016-01-01

    We report on the construction of generic models to calculate photosynthetically active radiation (PAR) from global horizontal irradiance (GHI), and vice versa. Our study took place at stations of the Greek UV network (UVNET) and the Hellenic solar energy network (HNSE) with measurements from NILU-UV multi-filter radiometers and CM pyranometers, chosen due to their long (≈1 M record/site) high temporal resolution (≈1 min) record that captures a broad range of atmospheric environments and cloudiness conditions. The uncertainty of the PAR measurements is quantified to be ±6.5% while the uncertainty involved in GHI measurements is up to ≈±7% according to the manufacturer. We show how multi-linear regression and nonlinear neural network (NN) models, trained at a calibration site (Thessaloniki) can be made generic provided that the input–output time series are processed with multi-channel singular spectrum analysis (M-SSA). Without M-SSA, both linear and nonlinear models perform well only locally. M-SSA with 50 time-lags is found to be sufficient for identification of trend, periodic and noise components in aerosol, cloud parameters and irradiance, and to construct regularized noise models of PAR from GHI irradiances. Reconstructed PAR and GHI time series capture ≈95% of the variance of the cross-validated target measurements and have median absolute percentage errors <2%. The intra-site median absolute error of M-SSA processed models were ≈8.2±1.7 W/m"2 for PAR and ≈9.2±4.2 W/m"2 for GHI. When applying the models trained at Thessaloniki to other stations, the average absolute mean bias between the model estimates and measured values was found to be ≈1.2 W/m"2 for PAR and ≈0.8 W/m"2 for GHI. For the models, percentage errors are well within the uncertainty of the measurements at all sites. Generic NN models were found to perform marginally better than their linear counterparts. - Highlights: • Generic linear regression and nonlinear neural network

  16. Estimation of daily global solar radiation as a function of the solar energy potential at soil surface

    Pereira, A.B.; Vrisman, A.L.; Galvani, E.

    2002-01-01

    The solar radiation received at the surface of the earth, apart from its relevance to several daily human activities, plays an important role in the growth and development of plants. The aim of the current work was to develop and gauge an estimation model for the evaluation of the global solar radiation flux density as a function of the solar energy potential at soil surface. Radiometric data were collected at Ponta Grossa, PR, Brazil (latitude 25°13' S, longitude 50°03' W, altitude 880 m). Estimated values of solar energy potential obtained as a function of only one measurement taken at solar noon time were confronted with those measured by a Robitzsch bimetalic actinograph, for days that presented insolation ratios higher than 0.85. This data set was submitted to a simple linear regression analysis, having been obtained a good adjustment between observed and calculated values. For the estimation of the coefficients a and b of Angström's equation, the method based on the solar energy potential at soil surface was used for the site under study. The methodology was efficient to assess the coefficients, aiming at the determination of the global solar radiation flux density, whith quickness and simplicity, having also found out that the criterium for the estimation of the solar energy potential is equivalent to that of the classical methodology of Angström. Knowledge of the available solar energy potential and global solar radiation flux density is of great importance for the estimation of the maximum atmospheric evaporative demand, of water consumption by irrigated crops, and also for building solar engineering equipment, such as driers, heaters, solar ovens, refrigerators, etc [pt

  17. Effects of UVB radiation on net community production in the upper global ocean

    Garcia-Corral, Lara S.; Holding, Johnna M.; Carrillo-de-Albornoz, Paloma; Steckbauer, Alexandra; Pé rez-Lorenzo, Marí a; Navarro, Nuria; Serret, Pablo; Duarte, Carlos M.; Agusti, Susana

    2016-01-01

    Our results suggest that earlier estimates of NCP for surface communities, which were hitherto derived using materials blocking UVB radiation were biased, with the direction and magnitude of this bias depending on the metabolic status of the communities and the underwater penetration of UVB radiation.

  18. Defining a Leader Role curriculum for radiation oncology: A global Delphi consensus study

    Turner, Sandra; Seel, Matthew; Trotter, Theresa; Giuliani, Meredith; Benstead, Kim; Eriksen, Jesper G.; Poortmans, Philip; Verfaillie, Christine; Westerveld, Henrike; Cross, Shamira; Chan, Ming-Ka; Shaw, Timothy

    2017-01-01

    The need for radiation oncologists and other radiation oncology (RO) professionals to lead quality improvement activities and contribute to shaping the future of our specialty is self-evident. Leadership knowledge, skills and behaviours, like other competencies, can be learned (Blumenthal et al.,

  19. Proceedings of INC 02. International Nuclear Conference 2002: Global Trends and Perspectives, Seminar V: Radiation Processing

    2002-01-01

    The papers discuss the folowing areas: radiation processing using low, medium and high energy electron beam, gamma and ultraviolet radiation; polymers blend; electron beam uses in wire, cables and polymers industry; studies of mechanical and tensile properties of elastomers / polymers blend

  20. Assessing the transferability of support vector machine model for estimation of global solar radiation from air temperature

    Chen, Ji-Long; Li, Guo-Sheng; Xiao, Bei-Bei; Wen, Zhao-Fei; Lv, Ming-Quan; Chen, Chun-Di; Jiang, Yi; Wang, Xiao-Xiao; Wu, Sheng-Jun

    2015-01-01

    Highlights: • Transferability of SVM in estimation of solar radiation is investigated. • Radiation at estimation site could be well estimated by SVM developed at source site. • A strategy for selecting a suitable source site is presented. • SVM accuracy is affected by distance and temperature difference between two sites. • RMSE of SVM shows logarithm or linearly relationship with altitude of source site. - Abstract: Exploring novel methods for estimation of global solar radiation from air temperature has been being a focus in many studies. This paper evaluates the transferability of support vector machines (SVM) for estimation of solar radiation in subtropical zone in China. Results suggest that solar radiation at one site (estimation site) could be well estimated by SVM model developed at another site (source site). The accuracy of estimation is affected by the distance and temperature difference between two sites, and altitude of source site. Higher correlations between RMSE of SVM and distance, and temperature differences are observed in northeastern region, increasing the reliability and confidence of SVM model developed at nearby stations. While lower correlations between RMSE and distance, and temperature differences are observed in southwest plateau region. When the altitude of estimation site is lower than 1200 m, RMSE show logarithm relationship with altitude of source sites where the altitude are lower than that of estimation site. Otherwise, RMSE show linearly relationship with altitude of source sites where the altitude are higher than 200 m but lower than that of the estimation site. This result suggests that solar radiation could be also estimated using SVM model developed at the site with similar but lower altitude. Based on these results, a strategy that takes into account the climatic conditions, topography, distance, and altitude for selecting a suitable source site is presented. The findings can guide and ease the appropriate choice of

  1. GLOBAL STRUCTURE OF THREE DISTINCT ACCRETION FLOWS AND OUTFLOWS AROUND BLACK HOLES FROM TWO-DIMENSIONAL RADIATION-MAGNETOHYDRODYNAMIC SIMULATIONS

    Ohsuga, Ken; Mineshige, Shin

    2011-01-01

    We present the detailed global structure of black hole accretion flows and outflows through newly performed two-dimensional radiation-magnetohydrodynamic simulations. By starting from a torus threaded with weak toroidal magnetic fields and by controlling the central density of the initial torus, ρ 0 , we can reproduce three distinct modes of accretion flow. In model A, which has the highest central density, an optically and geometrically thick supercritical accretion disk is created. The radiation force greatly exceeds the gravity above the disk surface, thereby driving a strong outflow (or jet). Because of mild beaming, the apparent (isotropic) photon luminosity is ∼22L E (where L E is the Eddington luminosity) in the face-on view. Even higher apparent luminosity is feasible if we increase the flow density. In model B, which has moderate density, radiative cooling of the accretion flow is so efficient that a standard-type, cold, and geometrically thin disk is formed at radii greater than ∼7 R S (where R S is the Schwarzschild radius), while the flow is radiatively inefficient otherwise. The magnetic-pressure-driven disk wind appears in this model. In model C, the density is too low for the flow to be radiatively efficient. The flow thus becomes radiatively inefficient accretion flow, which is geometrically thick and optically thin. The magnetic-pressure force, together with the gas-pressure force, drives outflows from the disk surface, and the flow releases its energy via jets rather than via radiation. Observational implications are briefly discussed.

  2. Influences on the reflectance of Arctic sea ice and the impact of anthropogenic impurities on the surface shortwave radiation balance

    Schulz, Hannes; Herber, Andreas; Birnbaum, Gerit; Seckmeyer, Gunther

    2014-01-01

    In order to investigate influences on the reflectance of snow covered Arctic sea ice, a discrete ordinate method and Mie-Theory based radiative transfer model has been set up. This model, the Snow on Sea Ice Model (SoSIM), is able to investigate changes in spectral and spectrally integrated (broadband) albedo of a multi-layer snow cover on sea ice due to varying snow microphysical parameters, atmospheric composition and incoming solar radiation. For typical conditions in the Arctic sea-ice ar...

  3. Penetration of UV-visible solar radiation in the global oceans: Insights from ocean color remote sensing

    Lee, Zhongping; Hu, Chuanmin; Shang, Shaoling; Du, Keping; Lewis, Marlon; Arnone, Robert; Brewin, Robert

    2013-09-01

    Penetration of solar radiation in the ocean is determined by the attenuation coefficient (Kd(λ)). Following radiative transfer theory, Kd is a function of angular distribution of incident light and water's absorption and backscattering coefficients. Because these optical products are now generated routinely from satellite measurements, it is logical to evolve the empirical Kd to a semianalytical Kd that is not only spectrally flexible, but also the sun-angle effect is accounted for explicitly. Here, the semianalytical model developed in Lee et al. (2005b) is revised to account for the shift of phase function between molecular and particulate scattering from the short to long wavelengths. Further, using field data collected independently from oligotrophic ocean to coastal waters covering >99% of the Kd range for the global oceans, the semianalytically derived Kd was evaluated and found to agree with measured data within ˜7-26%. The updated processing system was applied to MODIS measurements to reveal the penetration of UVA-visible radiation in the global oceans, where an empirical procedure to correct Raman effect was also included. The results indicated that the penetration of the blue-green radiation for most oceanic waters is ˜30-40% deeper than the commonly used euphotic zone depth; and confirmed that at a depth of 50-70 m there is still ˜10% of the surface UVA radiation (at 360 nm) in most oligotrophic waters. The results suggest a necessity to modify or expand the light attenuation product from satellite ocean-color measurements in order to be more applicable for studies of ocean physics and biogeochemistry.

  4. Riding the Banzai Pipeline at Jupiter: Balancing Low Delta-V and Low Radiation to Reach Europa

    McElrath, Timothy P.; Campagnola, Stefano; Strange, Nathan J.

    2012-01-01

    Europa's tantalizing allure as a possible haven for life comes cloaked in a myriad of challenges for robotic spacecraft exploration. Not only are the propulsive requirements high and the solar illumination low, but the radiation environment at Jupiter administers its inexorable death sentence on any electronics dispatched to closely examine the satellite. So to the usual trades of mass, delta-V, and cost, we must add radiation dose, which tugs the trajectory solution in a contrary direction. Previous studies have concluded that adding radiation shielding mass is more efficient than using ?V to reduce the exposure time, but that position was recently challenged by a study focusing on delivering simple landers to the Europa surface. During this work, a new trajectory option was found to occupy a strategic location in the delta-V/radiation continuum - we call it the "Banzai pipeline" due to the visual similarity with the end-on view down a breaking wave, as shown in the following figures.

  5. Estimation of monthly global solar radiation in the eastern Mediterranean region in Turkey by using artificial neural networks

    Sahan, Muhittin; Yakut, Emre

    2016-01-01

    In this study, an artificial neural network (ANN) model was used to estimate monthly average global solar radiation on a horizontal surface for selected 5 locations in Mediterranean region for period of 18 years (1993-2010). Meteorological and geographical data were taken from Turkish State Meteorological Service. The ANN architecture designed is a feed-forward back-propagation model with one-hidden layer containing 21 neurons with hyperbolic tangent sigmoid as the transfer function and one output layer utilized a linear transfer function (purelin). The training algorithm used in ANN model was the Levenberg Marquand back propagation algorith (trainlm). Results obtained from ANN model were compared with measured meteorological values by using statistical methods. A correlation coefficient of 97.97 (~98%) was obtained with root mean square error (RMSE) of 0.852 MJ/m 2 , mean square error (MSE) of 0.725 MJ/m 2 , mean absolute bias error (MABE) 10.659MJ/m 2 , and mean absolute percentage error (MAPE) of 4.8%. Results show good agreement between the estimated and measured values of global solar radiation. We suggest that the developed ANN model can be used to predict solar radiation another location and conditions

  6. Hydrologic and radiative feedbacks on extratropical transient eddies: Implications of global warming

    Gutowski, W.J. Jr.; Branscome, L.E.

    1994-01-01

    Atmospheric transient eddies contribute significantly to global energy and water cycles through their transports of sensible heat and water vapor. Changes in global climate induced by greenhouse enhancement will likely alter transient eddy behavior. General circulation models (GCMs) can simulate such alterations, but unraveling all the feedbacks that occur in GCMs is difficult

  7. Global real-time dose measurements using the Automated Radiation Measurements for Aerospace Safety (ARMAS) system

    Tobiska, W. Kent; Bouwer, D.; Smart, D.; Shea, M.; Bailey, J.; Didkovsky, L.; Judge, K.; Garrett, H.; Atwell, W.; Gersey, B.; Wilkins, R.; Rice, D.; Schunk, R.; Bell, D.; Mertens, C.; Xu, X.; Wiltberger, M.; Wiley, S.; Teets, E.; Jones, B.; Hong, S.; Yoon, K.

    2016-11-01

    The Automated Radiation Measurements for Aerospace Safety (ARMAS) program has successfully deployed a fleet of six instruments measuring the ambient radiation environment at commercial aircraft altitudes. ARMAS transmits real-time data to the ground and provides quality, tissue-relevant ambient dose equivalent rates with 5 min latency for dose rates on 213 flights up to 17.3 km (56,700 ft). We show five cases from different aircraft; the source particles are dominated by galactic cosmic rays but include particle fluxes for minor radiation periods and geomagnetically disturbed conditions. The measurements from 2013 to 2016 do not cover a period of time to quantify galactic cosmic rays' dependence on solar cycle variation and their effect on aviation radiation. However, we report on small radiation "clouds" in specific magnetic latitude regions and note that active geomagnetic, variable space weather conditions may sufficiently modify the magnetospheric magnetic field that can enhance the radiation environment, particularly at high altitudes and middle to high latitudes. When there is no significant space weather, high-latitude flights produce a dose rate analogous to a chest X-ray every 12.5 h, every 25 h for midlatitudes, and every 100 h for equatorial latitudes at typical commercial flight altitudes of 37,000 ft ( 11 km). The dose rate doubles every 2 km altitude increase, suggesting a radiation event management strategy for pilots or air traffic control; i.e., where event-driven radiation regions can be identified, they can be treated like volcanic ash clouds to achieve radiation safety goals with slightly lower flight altitudes or more equatorial flight paths.

  8. Comparison of several methods to calculate sunshine hours from global radiation; Vergelijking van diverse methodes voor de berekening van zonneschijnduur uit globale straling

    Schipper, J.

    2004-07-01

    A formal definition of sunshine duration by the World Meteorological Organisation (WMO) has allowed the development of automatic instruments for measuring sunshine hours. This defines sunshine hours as the sum of the time intervals (in hours) during which the direct (normal) solar irradiance exceeds a threshold of 120W{sup m-2} . The most complex (and most accurate) of these instruments are tracking pyrheliometers, where a collimated sensor automatically moves to track the movement of the sun. This reads the direct beam radiation only. Any reading over 120Wm{sup -2} is defined as being sunshine. However, as this type of sensor does not truly track the sun it requires regular adjustment to take into account the seasonal changes in solar declination. Also, this sensor is relatively expensive and has moving parts requiring extra power. A much simpler approach is to try to estimate sunshine hours from the single pyranometer/solarimeter of the type normally installed on most weather stations. As these sensors measure total global radiation the normal definition of 'sunshine' cannot be used. Simple fixed thresholds, as often used in low grade weather stations, do not give reliable answers either, as diffuse radiation from a completely cloudy sky in the summer will often exceed direct beam radiation in the winter. An alternative algorithm has been suggested by workers at the Royal Dutch Meteorological Institute (KNMI). They have proposed and tested an algorithm (Slob-algorithm) which defines sunshine as being when the measured global radiation (G) is greater than 0.4 times the potential solar radiation outside the earth's atmosphere on a horizontal surface (G{sub 0}). One long term test of this algorithm showed that estimates of sunshine hours were on average within 0.9 hours of the daily total. While this might appear to give rather poor accuracy compared to that one would expect for totalised solar radiation, they consider it accurate enough for normal

  9. Radiation accidents with global consequences for the population. Problems of risk evaluation

    Vasilev, G.; Doncheva, B.; Stoilova, S.; Miloslavov, V.; Tsenova, T.; Novkirishki, V.

    1987-01-01

    The theoretical problems concerning the delayed impacts as a result of considerable radiation accidents are discussed. The attention is paid to the maximum individual doses which are relatively low but many people are affected. In these cases, the risk evaluation is based on the cancerogenesis, genetic and teratogenetic consequences among the concerned population. The main equation of the linear threshold-free model 'dose effect' is subjected to analysis. Considering the real prognostic importance of this equation the following recommendations are made: further observation on epidemic diseases; investigation of teratogenetic consequences in connection with the radiation doses obtained during the antenatal development; radiation-hygienic standardization of the oral absorbtion of radionuclides for short and long periods of time; effective equivalent dose determination according to the irradiated organ or tissue (mammary glands, lungs, red marrow, gonads, skin); necessity of national system for in time announcement of radiation accidents, as well as suitable control of the internal and the external irradiation

  10. Photosynthetically Available Radiation, Aqua MODIS, NPP, 0.05 degrees, Global, Science Quality

    National Oceanic and Atmospheric Administration, Department of Commerce — MODIS measures photosynthetically available radiation that may be used to mode primary productivity. THIS IS AN EXPERIMENTAL PRODUCT: intended strictly for...

  11. Global Observations of Aerosols and Clouds from Combined Lidar and Passive Instruments to Improve Radiation Budget and Climate Studies

    Winker, David M.

    1999-01-01

    Current uncertainties in the effects of clouds and aerosols on the Earth radiation budget limit our understanding of the climate system and the potential for global climate change. Pathfinder Instruments for Cloud and Aerosol Spaceborne Observations - Climatologie Etendue des Nuages et des Aerosols (PICASSO-CENA) is a recently approved satellite mission within NASA's Earth System Science Pathfinder (ESSP) program which will address these uncertainties with a unique suite of active and passive instruments. The Lidar In-space Technology Experiment (LITE) demonstrated the potential benefits of space lidar for studies of clouds and aerosols. PICASSO-CENA builds on this experience with a payload consisting of a two-wavelength polarization-sensitive lidar, an oxygen A-band spectrometer (ABS), an imaging infrared radiometer (IIR), and a wide field camera (WFC). Data from these instruments will be used to measure the vertical distributions of aerosols and clouds in the atmosphere, as well as optical and physical properties of aerosols and clouds which influence the Earth radiation budget. PICASSO-CENA will be flown in formation with the PM satellite of the NASA Earth Observing System (EOS) to provide a comprehensive suite of coincident measurements of atmospheric state, aerosol and cloud optical properties, and radiative fluxes. The mission will address critical uncertainties iin the direct radiative forcing of aerosols and clouds as well as aerosol influences on cloud radiative properties and cloud-climate radiation feedbacks. PICASSO-CENA is planned for a three year mission, with a launch in early 2003. PICASSO-CENA is being developed within the framework of a collaboration between NASA and CNES.

  12. Estimation of available global solar radiation using sunshine duration over South Korea

    Das, Amrita; Park, Jin-ki; Park, Jong-hwa

    2015-11-01

    Besides designing a solar energy system, accurate insolation data is also a key component for many biological and atmospheric studies. But solar radiation stations are not widely available due to financial and technical limitations; this insufficient number affects the spatial resolution whenever an attempt is made to construct a solar radiation map. There are several models in literature for estimating incoming solar radiation using sunshine fraction. Seventeen of such models among which 6 are linear and 11 non-linear, have been chosen for studying and estimating solar radiation on a horizontal surface over South Korea. The better performance of a non-linear model signifies the fact that the relationship between sunshine duration and clearness index does not follow a straight line. With such a model solar radiation over 79 stations measuring sunshine duration is computed and used as input for spatial interpolation. Finally monthly solar radiation maps are constructed using the Ordinary Kriging method. The cross validation results show good agreement between observed and predicted data.

  13. Site specific X-ray induced changes in organic and metal organic compounds and their influence on global radiation damage

    Heintz, Desiree Ellen

    2012-07-01

    The aim of this work was to systematically investigate the effects of specific and global X-ray radiation damage to biological samples and obtain a conclusive model to describe the underlying principles. Based on the systematic studies performed in this work, it was possible to propose two conclusive mechanisms to describe X-ray induced photoreduction and global radiation damage. The influence of chemical composition, temperature and solvent on X-ray induced photoreduction was investigated by X-ray Absorption Near Edge Spectroscopy and single crystal X-ray diffraction of two B12 cofactors - cyano- and methylcobalamin - as well as iron(II) and iron(III) complexes. The obtained results revealed that X-ray induced photoreduction is a ligand dependent process, with a redox reaction taking place within the complex. It could further be shown that selective hydrogen abstraction plays an important role in the process of X-ray induced photoreduction. Based on the experimental results of this work, a model to describe X-ray induced photoreduction of metal organic complexes could be proposed. The process of X-ray induced hydrogen abstraction was further investigated in a combined X-ray and neutron diffraction study on the amino acids L-serine and L-alanine, which were used as model compounds for proteins, and the nucleoside deoxythymidine (thymidine) as a model for DNA. A damage mechanism for L-serine could be found. It involves the abstraction of two hydrogen atoms, one from the hydroxyl group and one from the adjacent methylene group. Such a hydrogen abstraction results in the formation of a carbonyl group. X-ray diffraction measurements on cyano- and methylcobalamin as well as on three metal amino acid complexes, containing nickel(II) and copper(II), respectively, were conducted to investigate the contribution of X-ray induced photoreduction to global radiation damage. Results from these measurements combined with the results from L-serine, L-alanine and thymidine allowed

  14. Site specific X-ray induced changes in organic and metal organic compounds and their influence on global radiation damage

    Heintz, Desiree Ellen

    2012-07-15

    The aim of this work was to systematically investigate the effects of specific and global X-ray radiation damage to biological samples and obtain a conclusive model to describe the underlying principles. Based on the systematic studies performed in this work, it was possible to propose two conclusive mechanisms to describe X-ray induced photoreduction and global radiation damage. The influence of chemical composition, temperature and solvent on X-ray induced photoreduction was investigated by X-ray Absorption Near Edge Spectroscopy and single crystal X-ray diffraction of two B12 cofactors - cyano- and methylcobalamin - as well as iron(II) and iron(III) complexes. The obtained results revealed that X-ray induced photoreduction is a ligand dependent process, with a redox reaction taking place within the complex. It could further be shown that selective hydrogen abstraction plays an important role in the process of X-ray induced photoreduction. Based on the experimental results of this work, a model to describe X-ray induced photoreduction of metal organic complexes could be proposed. The process of X-ray induced hydrogen abstraction was further investigated in a combined X-ray and neutron diffraction study on the amino acids L-serine and L-alanine, which were used as model compounds for proteins, and the nucleoside deoxythymidine (thymidine) as a model for DNA. A damage mechanism for L-serine could be found. It involves the abstraction of two hydrogen atoms, one from the hydroxyl group and one from the adjacent methylene group. Such a hydrogen abstraction results in the formation of a carbonyl group. X-ray diffraction measurements on cyano- and methylcobalamin as well as on three metal amino acid complexes, containing nickel(II) and copper(II), respectively, were conducted to investigate the contribution of X-ray induced photoreduction to global radiation damage. Results from these measurements combined with the results from L-serine, L-alanine and thymidine allowed

  15. Measuring and prediction of global solar ultraviolet radiation (0295-0385 μ m) under clear and cloudless skies

    Wright, Jaime

    2008-01-01

    Values of global solar ultraviolet radiation were measured with an ultraviolet radiometer and also predicted with a atmospheric spectral model. The values obtained with the atmospheric spectral model, based physically, were analyzed and compared with experimental values measured in situ. Measurements were performed for different zenith angles in conditions of clear skies in Heredia, Costa Rica. The necessary input data include latitude, altitude, surface albedo, Earth-Sun distance, as well as atmospheric characteristics: atmospheric turbidity, precipitable water and atmospheric ozone. The comparison between measured and predicted values have been successful. (author) [es

  16. Estimation of Radiative Efficiency of Chemicals with Potentially Significant Global Warming Potential

    U.S. Environmental Protection Agency — The set of commercially available chemical substances in commerce that may have significant global warming potential (GWP) is not well defined. Although there are...

  17. Enhanced Global Signal of Neutral Hydrogen Due to Excess Radiation at Cosmic Dawn

    Feng, Chang; Holder, Gilbert

    2018-05-01

    We revisit the global 21 cm signal calculation incorporating a possible radio background at early times, and find that the global 21 cm signal shows a much stronger absorption feature, which could enhance detection prospects for future 21 cm experiments. In light of recent reports of a possible low-frequency excess radio background, we propose that detailed 21 cm calculations should include a possible early radio background.

  18. Impact of Aerosols on Shortwave and Photosynthetically Active Radiation Balance over Sub-tropical Region in South Asia: Observational and Modeling Approach

    Subba, T.; Pathak, B.

    2016-12-01

    The North-East Indian Region (NER) (22-30ºN, 89-98ºE) in south Asia sandwiched between two global biodiversity hotspots namely, Himalaya and Indo-Burma, assumes significance owing to its unique topography with mountains in the north, east and south and densely populated Indo Gangetic plains (IGP) towards the west resulting in complex aerosol system. Multi-year (2010-2014) concurrent measurements of aerosol properties and the shortwave radiation budget are examined over four geographically distinct stations of NER operational under Indian Space Research organization's ARFINET (Aerosol Radiative Forcing over India NETwork). An attempt has been made to lessen the ambiguity of forcing estimation by validating the radiative transfer modelled ARF with the CNR4 net radiometer measured values (r2 0.98). The Normalized Difference Vegetation Index and its dependence on the extinction of the photosynthetically active radiation (PAR) due to aerosol are assessed. The spring time enhancement of aerosols in the column has shown significant surface cooling (ARF = -48 ± 5 Wm-2) over the region, while the very high Black Carbon (BC) mass concentrations near the surface (SSA > 0.8) leads to significant atmospheric warming (ARF = +41 ± 7 Wm-2) in the shortwave range. Radiative forcing estimates reveal that the atmospheric forcing by BC could be as high as +30Wm-2 over the western part, which are significantly higher than the eastern part with a consequent heating rate of 1.5 K day-1 revealing an east-west asymmetry over NER. The impact of BC aerosols on the photosynthetic rate varies among different locations ranging from -5±2 Wm-2 to -25±3 Wm-2. Almost 70% of the total atmospheric shortwave radiative absorption is attributed to just 10% contribution of Black Carbon (BC) to total mass concentration and causes a reduction of more than 30% of PAR reaching the surface over Brahmaputra valley due to direct radiative effect. Comparison of previous and the present study shows highest

  19. Balance Problems

    ... often, it could be a sign of a balance problem. Balance problems can make you feel unsteady. You may ... related injuries, such as a hip fracture. Some balance problems are due to problems in the inner ...

  20. Strengthening global norms for protecting nuclear materials - feedback on little countries radiation safety

    Chelidze, L.; Kakushadze, S.

    2002-01-01

    Full text: Georgia is the part of New Great Silk Road, connecting Europe and Asia. Along this rout will be laid oil and gas pipelines, transport and telecommunication lines. Unfortunately, besides economical communication, the rout can be used for illegal transit of nuclear materials. There is special concern regarding uncontrolled territories of conflict zones. Taking into consideration recent terrible terrorist acts we feel great responsibility for ensuring safety of this rout, which is a precondition of economical development and political stability of the whole Caucasian region A potentially hazardous radiological situation developed in Georgia with orphan radiation sources in the late 1990s and 2001: discovery of high-activity strong Radiation sources of (Strontium-90 from thermo-generators) in Tsalenjikha district. Eight such generators were brought to Georgia in 1984, and four of them have been found in Svanety mountainous region in addition to the two found in the Tsalenjikha, but remaining two are not yet found. During the last years several incidents of illicit trafficking were reported. The radiation problems greatly relate to the withdrawal of the Russian military bases. The radiological accident took place in Lilo, Georgia, when sealed radiation sources had been abandoned by a previous owner at a site. Taking into account the geopolitical location of Georgia it is quite important to strengthen the physical protection infrastructure in country with has serious territorial problems. The first step was to provide an appropriate legal framework for the safety management in the country and clearly identify regulatory body. The ministry implements state control in the nuclear and radiation safety field for protection of environment and natural resources of Georgia (hereinafter referred to as the Ministry). The Ministry is obliged to supervise the physical protection systems. The Ministry shall co-ordinate the state system of physical protection of the use

  1. GLOBAL ELECTROMAGNETIC RADIATION POLLUTION: RISK ASSESSMENT FROM FIELD MEASUREMENTS AND ANIMAL EXPERIMENTS

    Fragkopoulou, A. F.; Margaritis, L. H.

    2009-12-01

    The extended use of wireless technology throughout the globe in almost all developed and non-developed countries has forced a large number of scientists to get involved in the investigation of the effects. The major issue is that unlike other forms of radiation exposure, this “non-ionizing electromagnetic radiation” was not present throughout the evolution of life in earth and therefore there are no adaptive mechanisms evolved. All organisms are vulnerable to the possible effects of radiation depending on the actual exposure level. “Safety limits” on the power density have been proposed but ongoing research has shown that these limits are not really safe for humans, not mentioning the entire population of living creatures on earth. The so called “Electrosmog Pollution” originating from the numerous radio and TV stations, communication satellite emission, but most importantly from mobile phone mast antennas, are of major concern, because it is gradually increasing at exponential rate. Therefore the key question is, do living organisms react upon their exposure to fields of non ionizing electromagnetic radiation? To have this question answered extensive research is being performed in various laboratories. One approach of our research includes field measurements within houses and classrooms, since a considerable proportion of the population in each country is exposed to the radiation coming from the nearby mast stations, in order to make a risk assessment. The measurements showed that in many cases the actual radiation present was potentially harmful. In other words, although the measured values were below the national safety levels, nevertheless they were above the levels of other countries. Therefore it has been suggested that a new cellular network should be constructed in order to minimize radiation levels in living areas and schools. Our experimental work is focusing on the elucidation of the effects of non-ionizing EMFs on mice exposed to mobile

  2. Analyzing the dose-dependence of the Saccharomyces cerevisiae global transcriptional response to methyl methanesulfonate and ionizing radiation.

    Benton, Michael G; Somasundaram, Swetha; Glasner, Jeremy D; Palecek, Sean P

    2006-12-01

    One of the most crucial tasks for a cell to ensure its long term survival is preserving the integrity of its genetic heritage via maintenance of DNA structure and sequence. While the DNA damage response in the yeast Saccharomyces cerevisiae, a model eukaryotic organism, has been extensively studied, much remains to be elucidated about how the organism senses and responds to different types and doses of DNA damage. We have measured the global transcriptional response of S. cerevisiae to multiple doses of two representative DNA damaging agents, methyl methanesulfonate (MMS) and gamma radiation. Hierarchical clustering of genes with a statistically significant change in transcription illustrated the differences in the cellular responses to MMS and gamma radiation. Overall, MMS produced a larger transcriptional response than gamma radiation, and many of the genes modulated in response to MMS are involved in protein and translational regulation. Several clusters of coregulated genes whose responses varied with DNA damaging agent dose were identified. Perhaps the most interesting cluster contained four genes exhibiting biphasic induction in response to MMS dose. All of the genes (DUN1, RNR2, RNR4, and HUG1) are involved in the Mec1p kinase pathway known to respond to MMS, presumably due to stalled DNA replication forks. The biphasic responses of these genes suggest that the pathway is induced at lower levels as MMS dose increases. The genes in this cluster with a threefold or greater transcriptional response to gamma radiation all showed an increased induction with increasing gamma radiation dosage. Analyzing genome-wide transcriptional changes to multiple doses of external stresses enabled the identification of cellular responses that are modulated by magnitude of the stress, providing insights into how a cell deals with genotoxicity.

  3. Analyzing the dose-dependence of the Saccharomyces cerevisiae global transcriptional response to methyl methanesulfonate and ionizing radiation

    Glasner Jeremy D

    2006-12-01

    Full Text Available Abstract Background One of the most crucial tasks for a cell to ensure its long term survival is preserving the integrity of its genetic heritage via maintenance of DNA structure and sequence. While the DNA damage response in the yeast Saccharomyces cerevisiae, a model eukaryotic organism, has been extensively studied, much remains to be elucidated about how the organism senses and responds to different types and doses of DNA damage. We have measured the global transcriptional response of S. cerevisiae to multiple doses of two representative DNA damaging agents, methyl methanesulfonate (MMS and gamma radiation. Results Hierarchical clustering of genes with a statistically significant change in transcription illustrated the differences in the cellular responses to MMS and gamma radiation. Overall, MMS produced a larger transcriptional response than gamma radiation, and many of the genes modulated in response to MMS are involved in protein and translational regulation. Several clusters of coregulated genes whose responses varied with DNA damaging agent dose were identified. Perhaps the most interesting cluster contained four genes exhibiting biphasic induction in response to MMS dose. All of the genes (DUN1, RNR2, RNR4, and HUG1 are involved in the Mec1p kinase pathway known to respond to MMS, presumably due to stalled DNA replication forks. The biphasic responses of these genes suggest that the pathway is induced at lower levels as MMS dose increases. The genes in this cluster with a threefold or greater transcriptional response to gamma radiation all showed an increased induction with increasing gamma radiation dosage. Conclusion Analyzing genome-wide transcriptional changes to multiple doses of external stresses enabled the identification of cellular responses that are modulated by magnitude of the stress, providing insights into how a cell deals with genotoxicity.

  4. Role of homeostatic dis balance in formation of the late consequences for radiation exposure in Kazakhstan population

    Galich, B.V.; Belikhina, T.I.; Moldagaliev, T.Zh.; Tretyakova, E.B.

    2008-01-01

    The purpose of research is to study localizations and level of homeostatic disturbances in the key organism systems forming the social important illness for the realization of State and regional rehabilitation programs in the Kazakhstan population exposed to radiation and non-radiation risk factors. The object of research was the data of medical examinations in the exposed population living in Abaisky, Beskaragaisky, Zhanasemejsky districts of East-Kazakhstan area for the period from 1962 to 2006 in three time intervals: 1962-1966; 1968-1987; 2002-2006. The control data was the results of medical examination of the population of Shadrinskoe village of Pavlodar area and Kokpekty village of East-Kazakhstan area for the same time period. We have studied two dose groups: 1 group of exposed population (dose 0,5 > Sv); II group of exposed population (dose 0,2-0,25 Sv). Study of dynamics for prevalence of cardiovascular and gastrointestinal diseases connected with damage in haemopoietic, immune and vegetative homeostasis was carried out in 987 exposed persons and persons included to control group.

  5. A computation ANN model for quantifying the global solar radiation: A case study of Al-Aqabah-Jordan

    Abolgasem, I M; Alghoul, M A; Ruslan, M H; Chan, H Y; Khrit, N G; Sopian, K

    2015-01-01

    In this paper, a computation model is developed to predict the global solar radiation (GSR) in Aqaba city based on the data recorded with association of Artificial Neural Networks (ANN). The data used in this work are global solar radiation (GSR), sunshine duration, maximum and minimum air temperature and relative humidity. These data are available from Jordanian meteorological station over a period of two years. The quality of GSR forecasting is compared by using different Learning Algorithms. The decision of changing the ANN architecture is essentially based on the predicted results to obtain the best ANN model for monthly and seasonal GSR. Different configurations patterns were tested using available observed data. It was found that the model using mainly sunshine duration and air temperature as inputs gives accurate results. The ANN model efficiency and the mean square error values show that the prediction model is accurate. It is found that the effect of the three learning algorithms on the accuracy of the prediction model at the training and testing stages for each time scale is mostly within the same accuracy range. (paper)

  6. Global smooth solution of the Cauchy problem for a model of a radiative flow

    Ducomet, B.; Nečasová, Šárka

    2015-01-01

    Roč. 14, č. 1 (2015), s. 1-36 ISSN 0391-173X R&D Projects: GA ČR GA201/08/0012 Institutional support: RVO:67985840 Keywords : Navier - Stokes -Fourier system * radiative equilibrium Subject RIV: BA - General Mathematics Impact factor: 0.891, year: 2015 http://annaliscienze.sns.it/index.php?page=Article&id=332

  7. Global Performance of a Fast Parameterization Scheme for Estimating Surface Solar Radiation from MODIS data

    Tang, W.; Yang, K.; Sun, Z.; Qin, J.; Niu, X.

    2016-12-01

    A fast parameterization scheme named SUNFLUX is used in this study to estimate instantaneous surface solar radiation (SSR) based on products from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor onboard both Terra and Aqua platforms. The scheme mainly takes into account the absorption and scattering processes due to clouds, aerosols and gas in the atmosphere. The estimated instantaneous SSR is evaluated against surface observations obtained from seven stations of the Surface Radiation Budget Network (SURFRAD), four stations in the North China Plain (NCP) and 40 stations of the Baseline Surface Radiation Network (BSRN). The statistical results for evaluation against these three datasets show that the relative root-mean-square error (RMSE) values of SUNFLUX are less than 15%, 16% and 17%, respectively. Daily SSR is derived through temporal upscaling from the MODIS-based instantaneous SSR estimates, and is validated against surface observations. The relative RMSE values for daily SSR estimates are about 16% at the seven SURFRAD stations, four NCP stations, 40 BSRN stations and 90 China Meteorological Administration (CMA) radiation stations.

  8. Establishing a Global Radiation Oncology Collaboration in Education (GRaCE): Objectives and priorities

    Turner, S.; Eriksen, J.G.; Trotter, T.; Verfaillie, C.; Benstead, K.; Giuliani, M.; Poortmans, P.; Holt, T.; Brennan, S.; Potter, R.

    2015-01-01

    Representatives from countries and regions world-wide who have implemented modern competency-based radiation- or clinical oncology curricula for training medical specialists, met to determine the feasibility and value of an ongoing international collaboration. In this forum, educational leaders from

  9. The influence of eruption season on the global aerosol evolution and radiative impact of tropical volcanic eruptions

    M. Toohey

    2011-12-01

    Full Text Available Simulations of tropical volcanic eruptions using a general circulation model with coupled aerosol microphysics are used to assess the influence of season of eruption on the aerosol evolution and radiative impacts at the Earth's surface. This analysis is presented for eruptions with SO2 injection magnitudes of 17 and 700 Tg, the former consistent with estimates of the 1991 Mt. Pinatubo eruption, the later a near-"super eruption". For each eruption magnitude, simulations are performed with eruptions at 15° N, at four equally spaced times of year. Sensitivity to eruption season of aerosol optical depth (AOD, clear-sky and all-sky shortwave (SW radiative flux is quantified by first integrating each field for four years after the eruption, then calculating for each cumulative field the absolute or percent difference between the maximum and minimum response from the four eruption seasons. Eruption season has a significant influence on AOD and clear-sky SW radiative flux anomalies for both eruption magnitudes. The sensitivity to eruption season for both fields is generally weak in the tropics, but increases in the mid- and high latitudes, reaching maximum values of ~75 %. Global mean AOD and clear-sky SW anomalies show sensitivity to eruption season on the order of 15–20 %, which results from differences in aerosol effective radius for the different eruption seasons. Smallest aerosol size and largest cumulative impact result from a January eruption for Pinatubo-magnitude eruption, and from a July eruption for the near-super eruption. In contrast to AOD and clear-sky SW anomalies, all-sky SW anomalies are found to be insensitive to season of eruption for the Pinatubo-magnitude eruption experiment, due to the reflection of solar radiation by clouds in the mid- to high latitudes. However, differences in all-sky SW anomalies between eruptions in different seasons are significant for the larger eruption magnitude, and the ~15 % sensitivity to

  10. Induction of CTGF by TGF-β1 in normal and radiation enteritis human smooth muscle cells: Smad/Rho balance and therapeutic perspectives

    Haydont, Valerie; Mathe, Denis; Bourgier, Celine; Abdelali, Jalil; Aigueperse, Jocelyne; Bourhis, Jean; Vozenin-Brotons, Marie-Catherine

    2005-01-01

    Background and purpose: Transforming Growth Factor β1 (TGF-β1) and its downstream effector Connective Tissue Growth Factor (CTGF/CCN2), are well known fibrogenic activators and we previously showed that the Rho/ROCK pathway controls CTGF expression in intestinal smooth muscle cells isolated from patients with delayed radiation enteritis. The aim of the present work was to investigate the balance between Smad and Rho signalling pathways in the TGF-β1 CTGF induction and modulation of radiation-induced fibrogenic differentiation after addition of pravastatin, an inhibitor of Rho isoprenylation. Patients and methods: Primary human smooth muscle cells isolated from normal (N-SMC) or radiation enteritis (RE-SMC) biopsies were incubated with TGF-β1 (10 ng/ml). Induction of CTGF, as well as nucleo-cytoplasmic distribution of phospho-Smad2/3, Smad2/3 and Smad4 were analysed by Western blot and immunocytochemistry. Smad DNA binding was assessed by EMSA and Rho activation was measured by pull-down assay. Results: After TGF-β1 addition, Smads were translocated to the nucleus in both cell types. Nuclear accumulation of Smad as well as their DNA-binding activity were higher in N-SMC than in RE-SMC, whereas the opposite was observed for Rho activation, suggesting a main involvement of Rho pathway in sustained fibrogenic differentiation. This hypothesis was further supported by the antifibrotic effect observed in vitro after cell treatment with pravastatin (i.e. decreased expression of CTGF, TGF-β1 and Collagen Iα2). Conclusions: Our results suggest that TGF-β1-induced CTGF transactivation mainly depends on the Smad pathway in N-SMC, whereas in RE-SMC, Smad and Rho pathways are involved. Inhibition of Rho activity by pravastatin alters fibrogenic differentiation in vitro which opens up new therapeutic perspectives

  11. Inter-comparison of the solar UVB, UVA and global radiation clearness and UV indices for Beer Sheva and Neve Zohar (Dead Sea), Israel

    Kudish, A.I.; Lyubansky, V.; Evseev, E.G.; Ianetz, A.

    2005-01-01

    An inter-comparison of the clearness indices for the solar UVB, UVA and global radiation for Beer Sheva and Neve Zohar (Dead Sea) are presented utilizing radiation data measured from January 1995 through December 2001 for which there is a one-to-one correspondence between the measurements, viz., any day for which a hourly value for one of the sites was missing is rejected and not included in the analysis for that particular radiation type. Beer Sheva is located ca. 65 km to the west and is approximately 700 m above Neve Zohar, which is located on the western shore of the Dead Sea. The Dead Sea is the lowest terrestrial point on the earth, approximately 400 m below mean sea level. The relative magnitudes of the global, UVB and UVA radiation intensities at the two sites can be attributed to the enhanced scattering at the Dead Sea due to the longer optical path length the solar radiation must traverse at the Dead Sea. The degree of attenuation due to scattering phenomena is inversely proportional to the wavelength raised to some power and, consequently, it is greatest for UVB and very small for global radiation. The UVB and UVA solar constants were determined from the extraterrestrial radiation values tabulated by Froehlich and Wehrli [Spectral distribution of solar irradiance from 25000 nm to 250nm, in: M. Iqbal, An introduction to solar radiation, Academic Press, New York, 1981, Appendix C, pp. 380-381]. The clearness indices for global and UVA radiation were of similar magnitude, whereas those for UVB radiation were of two orders of magnitude smaller. In addition, the monthly average hourly UV Index at both sites has also been determined and an inter-comparison of the values has been performed for all available hourly values from January 1995 through August 2002 for both sites. It is observed that the monthly average hourly UV Index values at the Dead Sea are never in the extreme range

  12. SU-F-E-14: Global Radiation Oncology Education and Training in Medical Physics Powered by Information and Communication Technologies

    Ngwa, W; Sajo, E; Ngoma, T; Dachi, J; Julius Mwaiselage, J; Kenton, O; Avery, S

    2016-01-01

    Purpose: Recent publications have highlighted the potential of Information and Communication Technologies (ICTs) to catalyze collaborations in cancer care, research and education in global radiation oncology. This work reports on the use of ICTs for global Medical Physics education and training across three countries: USA, Tanzania and Kuwait Methods: An online education platform was established by Radiation Oncology Faculty from Harvard Medical School, and the University of Pennsylvania with integrated Medical Physics Course modules accessible to trainees in Tanzania via partnership with the Muhimbili University of Health and Allied Sciences, and the Ocean Road Cancer Institute. The course modules incorporated lectures covering Radiation Therapy Physics with videos, discussion board, assessments and grade center. Faculty at Harvard Medical School and the University of Massachusetts Lowell also employed weekly Skype meetings to train/mentor three graduate students, living out-of-state and in Kuwait for up to 9 research credits per semester for over two semesters towards obtaining their graduate degrees Results: Students were able to successfully access the Medical Physics course modules and participate in learning activities, online discussion boards, and assessments. Other instructors could also access/co-teach the course modules from USA and Tanzania. Meanwhile all three graduate students with remote training via Skype and email made major progress in their graduate training with each one of them submitting their research results as abstracts to be presented at the 2016 AAPM conference. One student has also published her work already and all three are developing these abstracts for publication in peer-reviewed journals. Conclusion: Altogether, this work highlights concrete examples/model on how ICTs can be used for capacity building in Medical Physics across continents, for both education and research training needed for Masters/PhD degrees. The developed modules

  13. SU-F-E-14: Global Radiation Oncology Education and Training in Medical Physics Powered by Information and Communication Technologies

    Ngwa, W [Harvard Medical School, Boston, MA (United States); University Massachusetts Lowell, Lowell, MA (United States); Sajo, E [University Massachusetts Lowell, Lowell, MA (United States); Ngoma, T [Muhimbili University of Health and Allied Sciences, Dar Es Salaam, TA (Tanzania, United Republic of); Dachi, J; Julius Mwaiselage, J [Ocean Road Cancer Institute, Dar Es Salaam (Tanzania, United Republic of); Kenton, O [University of Pennsylvania, Philadelphia, Pennsylvania (United States); Avery, S [University of Pennsylvania, Sicklerville, NJ (United States)

    2016-06-15

    Purpose: Recent publications have highlighted the potential of Information and Communication Technologies (ICTs) to catalyze collaborations in cancer care, research and education in global radiation oncology. This work reports on the use of ICTs for global Medical Physics education and training across three countries: USA, Tanzania and Kuwait Methods: An online education platform was established by Radiation Oncology Faculty from Harvard Medical School, and the University of Pennsylvania with integrated Medical Physics Course modules accessible to trainees in Tanzania via partnership with the Muhimbili University of Health and Allied Sciences, and the Ocean Road Cancer Institute. The course modules incorporated lectures covering Radiation Therapy Physics with videos, discussion board, assessments and grade center. Faculty at Harvard Medical School and the University of Massachusetts Lowell also employed weekly Skype meetings to train/mentor three graduate students, living out-of-state and in Kuwait for up to 9 research credits per semester for over two semesters towards obtaining their graduate degrees Results: Students were able to successfully access the Medical Physics course modules and participate in learning activities, online discussion boards, and assessments. Other instructors could also access/co-teach the course modules from USA and Tanzania. Meanwhile all three graduate students with remote training via Skype and email made major progress in their graduate training with each one of them submitting their research results as abstracts to be presented at the 2016 AAPM conference. One student has also published her work already and all three are developing these abstracts for publication in peer-reviewed journals. Conclusion: Altogether, this work highlights concrete examples/model on how ICTs can be used for capacity building in Medical Physics across continents, for both education and research training needed for Masters/PhD degrees. The developed modules

  14. A new hybrid support vector machine–wavelet transform approach for estimation of horizontal global solar radiation

    Mohammadi, Kasra; Shamshirband, Shahaboddin; Tong, Chong Wen; Arif, Muhammad; Petković, Dalibor; Ch, Sudheer

    2015-01-01

    Highlights: • Horizontal global solar radiation (HGSR) is predicted based on a new hybrid approach. • Support Vector Machines and Wavelet Transform algorithm (SVM–WT) are combined. • Different sets of meteorological elements are used to predict HGSR. • The precision of SVM–WT is assessed thoroughly against ANN, GP and ARMA. • SVM–WT would be an appealing approach to predict HGSR and outperforms others. - Abstract: In this paper, a new hybrid approach by combining the Support Vector Machine (SVM) with Wavelet Transform (WT) algorithm is developed to predict horizontal global solar radiation. The predictions are conducted on both daily and monthly mean scales for an Iranian coastal city. The proposed SVM–WT method is compared against other existing techniques to demonstrate its efficiency and viability. Three different sets of parameters are served as inputs to establish three models. The results indicate that the model using relative sunshine duration, difference between air temperatures, relative humidity, average temperature and extraterrestrial solar radiation as inputs shows higher performance than other models. The statistical analysis demonstrates that SVM–WT approach enjoys very good performance and outperforms other approaches. For the best SVM–WT model, the obtained statistical indicators of mean absolute percentage error, mean absolute bias error, root mean square error, relative root mean square error and coefficient of determination for daily estimation are 6.9996%, 0.8405 MJ/m 2 , 1.4245 MJ/m 2 , 7.9467% and 0.9086, respectively. Also, for monthly mean estimation the values are 3.2601%, 0.5104 MJ/m 2 , 0.6618 MJ/m 2 , 3.6935% and 0.9742, respectively. Based upon relative percentage error, for the best SVM–WT model, 88.70% of daily predictions fall within the acceptable range of −10% to +10%

  15. A New Database of Global and Direct Solar Radiation Using the Eastern Meteosat Satellite, Models and Validation

    Ana Gracia Amillo

    2014-08-01

    Full Text Available We present a new database of solar radiation at ground level for Eastern Europe and Africa, the Middle East and Asia, estimated using satellite images from the Meteosat East geostationary satellites. The method presented calculates global horizontal (G and direct normal irradiance (DNI at hourly intervals, using the full Meteosat archive from 1998 to present. Validation of the estimated global horizontal and direct normal irradiance values has been performed by comparison with high-quality ground station measurements. Due to the low number of ground measurements in the viewing area of the Meteosat Eastern satellites, the validation of the calculation method has been extended by a comparison of the estimated values derived from the same class of satellites but positioned at 0°E, where more ground stations are available. Results show a low overall mean bias deviation (MBD of +1.63 Wm−2 or +0.73% for global horizontal irradiance. The mean absolute bias of the individual station MBD is 2.36%, while the root mean square deviation of the individual MBD values is 3.18%. For direct normal irradiance the corresponding values are overall MBD of +0.61 Wm−2 or +0.62%, while the mean absolute bias of the individual station MBD is 5.03% and the root mean square deviation of the individual MBD values is 6.30%. The resulting database of hourly solar radiation values will be made freely available. These data will also be integrated into the PVGIS web application to allow users to estimate the energy output of photovoltaic (PV systems not only in Europe and Africa, but now also in Asia.

  16. On Effective Radiative Forcing of Partial Internally and Externally Mixed Aerosols and Their Effects on Global Climate

    Zhou, Chen; Zhang, Hua; Zhao, Shuyun; Li, Jiangnan

    2018-01-01

    The total effective radiative forcing (ERF) due to partial internally mixed (PIM) and externally mixed (EM) anthropogenic aerosols, as well as their climatic effects since the year of 1850, was evaluated and compared using the aerosol-climate online coupled model of BCC_AGCM2.0_CUACE/Aero. The influences of internal mixing (IM) on aerosol hygroscopicity parameter, optical properties, and concentration were considered. Generally, IM could markedly weaken the negative ERF and cooling effects of anthropogenic aerosols. The global annual mean ERF of EM anthropogenic aerosols from 1850 to 2010 was -1.87 W m-2, of which the aerosol-radiation interactive ERF (ERFari) and aerosol-cloud interactive ERF (ERFaci) were -0.49 and -1.38 W m-2, respectively. The global annual mean ERF due to PIM anthropogenic aerosols from 1850 to 2010 was -1.23 W m-2, with ERFari and ERFaci of -0.23 and -1.01 W m-2, respectively. The global annual mean surface temperature and water evaporation and precipitation were reduced by 1.74 K and 0.14 mm d-1 for EM scheme and 1.28 K and 0.11 mm d-1 for PIM scheme, respectively. However, the relative humidity near the surface was slightly increased for both mixing cases. The Intertropical Convergence Zone was southwardly shifted for both EM and PIM cases but was less southwardly shifted in PIM scheme due to the less reduction in atmospheric temperature in the midlatitude and low latitude of the Northern Hemisphere.

  17. Balance Problems

    ... fully trust your sense of balance. Loss of balance also raises the risk of falls. This is a serious and even life-threatening ... 65. Balance disorders are serious because of the risk of falls. But occasionally balance problems may warn of another health condition, such ...

  18. Global analysis of cloud field coverage and radiative properties, using morphological methods and MODIS observations

    R. Z. Bar-Or

    2011-01-01

    Full Text Available The recently recognized continuous transition zone between detectable clouds and cloud-free atmosphere ("the twilight zone" is affected by undetectable clouds and humidified aerosol. In this study, we suggest to distinguish cloud fields (including the detectable clouds and the surrounding twilight zone from cloud-free areas, which are not affected by clouds. For this classification, a robust and simple-to-implement cloud field masking algorithm which uses only the spatial distribution of clouds, is presented in detail. A global analysis, estimating Earth's cloud field coverage (50° S–50° N for 28 July 2008, using the Moderate Resolution Imaging Spectroradiometer (MODIS data, finds that while the declared cloud fraction is 51%, the global cloud field coverage reaches 88%. The results reveal the low likelihood for finding a cloud-free pixel and suggest that this likelihood may decrease as the pixel size becomes larger. A global latitudinal analysis of cloud fields finds that unlike oceans, which are more uniformly covered by cloud fields, land areas located under the subsidence zones of the Hadley cell (the desert belts, contain proper areas for investigating cloud-free atmosphere as there is 40–80% probability to detect clear sky over them. Usually these golden-pixels, with higher likelihood to be free of clouds, are over deserts. Independent global statistical analysis, using MODIS aerosol and cloud products, reveals a sharp exponential decay of the global mean aerosol optical depth (AOD as a function of the distance from the nearest detectable cloud, both above ocean and land. Similar statistical analysis finds an exponential growth of mean aerosol fine-mode fraction (FMF over oceans when the distance from the nearest cloud increases. A 30 km scale break clearly appears in several analyses here, suggesting this is a typical natural scale of cloud fields. This work shows different microphysical and optical properties of cloud fields

  19. Multiresolution analysis of the spatiotemporal variability in global radiation observed by a dense network of 99 pyranometers

    Lakshmi Madhavan, Bomidi; Deneke, Hartwig; Witthuhn, Jonas; Macke, Andreas

    2017-03-01

    The time series of global radiation observed by a dense network of 99 autonomous pyranometers during the HOPE campaign around Jülich, Germany, are investigated with a multiresolution analysis based on the maximum overlap discrete wavelet transform and the Haar wavelet. For different sky conditions, typical wavelet power spectra are calculated to quantify the timescale dependence of variability in global transmittance. Distinctly higher variability is observed at all frequencies in the power spectra of global transmittance under broken-cloud conditions compared to clear, cirrus, or overcast skies. The spatial autocorrelation function including its frequency dependence is determined to quantify the degree of similarity of two time series measurements as a function of their spatial separation. Distances ranging from 100 m to 10 km are considered, and a rapid decrease of the autocorrelation function is found with increasing frequency and distance. For frequencies above 1/3 min-1 and points separated by more than 1 km, variations in transmittance become completely uncorrelated. A method is introduced to estimate the deviation between a point measurement and a spatially averaged value for a surrounding domain, which takes into account domain size and averaging period, and is used to explore the representativeness of a single pyranometer observation for its surrounding region. Two distinct mechanisms are identified, which limit the representativeness; on the one hand, spatial averaging reduces variability and thus modifies the shape of the power spectrum. On the other hand, the correlation of variations of the spatially averaged field and a point measurement decreases rapidly with increasing temporal frequency. For a grid box of 10 km × 10 km and averaging periods of 1.5-3 h, the deviation of global transmittance between a point measurement and an area-averaged value depends on the prevailing sky conditions: 2.8 (clear), 1.8 (cirrus), 1.5 (overcast), and 4.2 % (broken

  20. An Evaluation of C1-C3 Hydrochlorofluorocarbon (HCFC) Metrics: Lifetimes, Ozone Depletion Potentials, Radiative Efficiencies, Global Warming and Global Temperature Potentials

    Burkholder, J. B.; Papanastasiou, D. K.; Marshall, P.

    2017-12-01

    Hydrochlorofluorocarbons (HCFCs) have been used as chlorofluorocarbon (CFC) substitutes in a number of applications, e.g. refrigerator and air-conditioning systems. Although HCFCs have lower ozone-depletion potentials (ODPs) compared to CFCs, they are potent greenhouse gases. The twenty-eighth meeting of the parties to the Montreal Protocol on Substances that Deplete the Ozone Layer (Kigali, 2016) included a list of 274 HCFCs to be controlled under the Montreal Protocol. However, from this list, only 15 of the HCFCs have values for their atmospheric lifetime, ODP, global warming potential (GWP), and global temperature potential (GTP) that are based on fundamental experimental studies, while 48 are registered compounds. In this work, we present a comprehensive evaluation of the atmospheric lifetimes, ODPs, radiative efficiencies (REs), GWPs, and GTPs for all 274 HCFCs to be included in the Montreal Protocol. Atmospheric lifetimes were estimated based on HCFC reactivity with OH radicals and O(1D), as well as their removal by UV photolysis using structure activity relationships and reactivity trends. ODP values are based on the semi-empirical approach described in the WMO/UNEP ozone assessment. Radiative efficiencies were estimated, based on infrared spectra calculated using theoretical electronic structure methods (Gaussian 09). GWPs and GTPs were calculated relative to CO2 using our estimated atmospheric lifetimes and REs. The details of the methodology will be discussed as well as the associated uncertainties. This study has provided a consistent set of atmospheric metrics for a wide range of HCFCs that support future policy decisions. More accurate metrics for a specific HCFC, if desired, would require fundamental laboratory studies to better define the OH reactivity and infrared absorption spectrum of the compound of interest. Overall, HCFCs within the same family (isomers) show a large ODP, GWP, GTP dependence on the molecular geometry of the isomers. The

  1. Global albedo change and radiative cooling from anthropogenic land cover change, 1700 to 2005 based on MODIS, land use harmonization, radiative kernels, and reanalysis

    Ghimire, Bardan; Williams, Christopher A.; Masek, Jeffrey; Gao, Feng; Wang, Zhuosen; Schaaf, Crystal; He, Tao

    2014-12-01

    Widespread anthropogenic land cover change over the last five centuries has influenced the global climate system through both biogeochemical and biophysical processes. Models indicate that warming from carbon emissions associated with land cover conversion has been partially offset by cooling from elevated albedo, but considerable uncertainty remains partly because of uncertainty in model treatments of albedo. This study incorporates a new spatially and temporally explicit, land cover specific albedo product derived from Moderate Resolution Imaging Spectroradiometer with a historical land use data set (Land Use Harmonization product) to provide more precise, observationally derived estimates of albedo impacts from anthropogenic land cover change with a complete range of data set specific uncertainty. The mean annual global albedo increase due to land cover change during 1700-2005 was estimated as 0.00106 ± 0.00008 (mean ± standard deviation), mainly driven by snow exposure due to land cover transitions from natural vegetation to agriculture. This translates to a top-of-atmosphere radiative cooling of -0.15 ± 0.1 W m-2 (mean ± standard deviation). Our estimate was in the middle of the Intergovernmental Panel on Climate Change Fifth Assessment Report range of -0.05 to -0.25 W m-2 and incorporates variability in albedo within land cover classes.

  2. History of chemically and radiatively important atmospheric gases from the Advanced Global Atmospheric Gases Experiment (AGAGE

    R. G. Prinn

    2018-06-01

    Full Text Available We present the organization, instrumentation, datasets, data interpretation, modeling, and accomplishments of the multinational global atmospheric measurement program AGAGE (Advanced Global Atmospheric Gases Experiment. AGAGE is distinguished by its capability to measure globally, at high frequency, and at multiple sites all the important species in the Montreal Protocol and all the important non-carbon-dioxide (non-CO2 gases assessed by the Intergovernmental Panel on Climate Change (CO2 is also measured at several sites. The scientific objectives of AGAGE are important in furthering our understanding of global chemical and climatic phenomena. They are the following: (1 to accurately measure the temporal and spatial distributions of anthropogenic gases that contribute the majority of reactive halogen to the stratosphere and/or are strong infrared absorbers (chlorocarbons, chlorofluorocarbons – CFCs, bromocarbons, hydrochlorofluorocarbons – HCFCs, hydrofluorocarbons – HFCs and polyfluorinated compounds (perfluorocarbons – PFCs, nitrogen trifluoride – NF3, sulfuryl fluoride – SO2F2, and sulfur hexafluoride – SF6 and use these measurements to determine the global rates of their emission and/or destruction (i.e., lifetimes; (2 to accurately measure the global distributions and temporal behaviors and determine the sources and sinks of non-CO2 biogenic–anthropogenic gases important to climate change and/or ozone depletion (methane – CH4, nitrous oxide – N2O, carbon monoxide – CO, molecular hydrogen – H2, methyl chloride – CH3Cl, and methyl bromide – CH3Br; (3 to identify new long-lived greenhouse and ozone-depleting gases (e.g., SO2F2, NF3, heavy PFCs (C4F10, C5F12, C6F14, C7F16, and C8F18 and hydrofluoroolefins (HFOs; e.g., CH2  =  CFCF3 have been identified in AGAGE, initiate the real-time monitoring of these new gases, and reconstruct their past histories from AGAGE, air archive, and firn air measurements; (4

  3. Global micro RNA expression in papillary thyroid carcinomas of young patients exposed to radiation

    Unger, K.; Elmahjoub, A.; Thomas, G. [Human Cancer Studies Group, Surgery and Cancer, Imperial College London, London (United Kingdom); Bogdanova, T. [Institute of Endocrinology and Metabolism, Academy of Medical Sciences of the Ukraine, Kiew (Ukraine)

    2012-07-01

    One of the main effects of the Chernobyl reactor accident is an increase in childhood papillary thyroid carcinomas (PTC) in the regions that were contaminated with radio-iodine from the fallout. Despite a considerable research effort, molecular profiles have yet to be identified that reliably distinguish between age matched patients with radiation associated and sporadic PTCs. Expression of micro RNAs (miRNA) have recently been studied extensively in many different cancer types. MiRNAs have the potential to provide insights into the network of molecular pathways that are involved in the development of tumorigenesis as they are involved in the regulation of networks of mRNAs. In addition, miRNAs can be studied in formalin-fixed paraffin embedded material, making them ideal for clinical studies. This study was designed specifically to identify differentially expressed miRNAs in patients with childhood PTC that were exposed (n=11) and non-exposed (n=9) to irradiation. The results suggest that in radiation-associated childhood PTC DNA repair processes which are reflected by genes that encode DNA-binding proteins are de-regulated. DNA mutation and double-strand breaks are induced by ionising radiation and subsequent mis-repair and inactivation of tumour suppressor genes and the activation of oncogenes leads to growth and proliferation of the tumour cell. These findings suggest that in addition to the MAP kinase pathway which is known to be a key pathway in PTC, additional pathways such as the Fc epsilon RI signalling, the VEGF pathway and p53 signalling pathway seem to be involved in radiation-associated tumorigenesis of PTC

  4. Global existence of a weak solution for a model in radiation magnetohydrodynamics

    Ducomet, B.; Kobera, M.; Nečasová, Šárka

    2017-01-01

    Roč. 150, č. 1 (2017), s. 43-65 ISSN 0167-8019 R&D Projects: GA ČR GA13-00522S Institutional support: RVO:67985840 Keywords : radiation magnetohydrodynamics * Navier-Stokes- Fourier system * weak solutio Subject RIV: BA - General Mathematics OBOR OECD: Pure mathematics Impact factor: 0.702, year: 2016 https://link.springer.com/article/10.1007%2Fs10440-016-0093-y

  5. Global micro RNA expression in papillary thyroid carcinomas of young patients exposed to radiation

    Unger, K.; Elmahjoub, A.; Thomas, G.; Bogdanova, T.

    2012-01-01

    One of the main effects of the Chernobyl reactor accident is an increase in childhood papillary thyroid carcinomas (PTC) in the regions that were contaminated with radio-iodine from the fallout. Despite a considerable research effort, molecular profiles have yet to be identified that reliably distinguish between age matched patients with radiation associated and sporadic PTCs. Expression of micro RNAs (miRNA) have recently been studied extensively in many different cancer types. MiRNAs have the potential to provide insights into the network of molecular pathways that are involved in the development of tumorigenesis as they are involved in the regulation of networks of mRNAs. In addition, miRNAs can be studied in formalin-fixed paraffin embedded material, making them ideal for clinical studies. This study was designed specifically to identify differentially expressed miRNAs in patients with childhood PTC that were exposed (n=11) and non-exposed (n=9) to irradiation. The results suggest that in radiation-associated childhood PTC DNA repair processes which are reflected by genes that encode DNA-binding proteins are de-regulated. DNA mutation and double-strand breaks are induced by ionising radiation and subsequent mis-repair and inactivation of tumour suppressor genes and the activation of oncogenes leads to growth and proliferation of the tumour cell. These findings suggest that in addition to the MAP kinase pathway which is known to be a key pathway in PTC, additional pathways such as the Fc epsilon RI signalling, the VEGF pathway and p53 signalling pathway seem to be involved in radiation-associated tumorigenesis of PTC

  6. Global existence of a weak solution for a model in radiation magnetohydrodynamics

    Ducomet, B.; Kobera, M.; Nečasová, Šárka

    2017-01-01

    Roč. 150, č. 1 (2017), s. 43-65 ISSN 0167-8019 R&D Projects: GA ČR GA13-00522S Institutional support: RVO:67985840 Keywords : radiation magnetohydrodynamics * Navier-Stokes-Fourier system * weak solutio Subject RIV: BA - General Mathematics OBOR OECD: Pure mathematics Impact factor: 0.702, year: 2016 https://link.springer.com/article/10.1007%2Fs10440-016-0093-y

  7. A Global Three-Dimensional Radiation Hydrodynamic Simulation of a Self-Gravitating Accretion Disk

    Phillipson, Rebecca; Vogeley, Michael S.; McMillan, Stephen; Boyd, Patricia

    2018-01-01

    We present three-dimensional, radiation hydrodynamic simulations of initially thin accretion disks with self-gravity using the grid-based code PLUTO. We produce simulated light curves and spectral energy distributions and compare to observational data of X-ray binary (XRB) and active galactic nuclei (AGN) variability. These simulations are of interest for modeling the role of radiation in accretion physics across decades of mass and frequency. In particular, the characteristics of the time variability in various bandwidths can probe the timescales over which different physical processes dominate the accretion flow. For example, in the case of some XRBs, superorbital periods much longer than the companion orbital period have been observed. Smoothed particle hydrodynamics (SPH) calculations have shown that irradiation-driven warping could be the mechanism underlying these long periods. In the case of AGN, irradiation-driven warping is also predicted to occur in addition to strong outflows originating from thermal and radiation pressure driving forces, which are important processes in understanding feedback and star formation in active galaxies. We compare our simulations to various toy models via traditional time series analysis of our synthetic and observed light curves.

  8. Modelling radiation-induced cell death and tumour re-oxygenation: local versus global and instant versus delayed cell death

    Gago-Arias, Araceli; Espinoza, Ignacio; Sánchez-Nieto, Beatriz; Aguiar, Pablo; Pardo-Montero, Juan

    2016-01-01

    The resistance of hypoxic cells to radiation, due to the oxygen dependence of radiosensitivity, is well known and must be taken into account to accurately calculate the radiation induced cell death. A proper modelling of the response of tumours to radiation requires deriving the distribution of oxygen at a microscopic scale. This usually involves solving the reaction-diffusion equation in tumour voxels using a vascularization distribution model. Moreover, re-oxygenation arises during the course of radiotherapy, one reason being the increase of available oxygen caused by cell killing, which can turn hypoxic tumours into oxic. In this work we study the effect of cell death kinetics in tumour oxygenation modelling, analysing how it affects the timing of re-oxygenation, surviving fraction and tumour control. Two models of cell death are compared, an instantaneous cell killing, mimicking early apoptosis, and a delayed cell death scenario in which cells can die shortly after being damaged, as well as long after irradiation. For each of these scenarios, the decrease in oxygen consumption due to cell death can be computed globally (macroscopic voxel average) or locally (microscopic). A re-oxygenation model already used in the literature, the so called full re-oxygenation, is also considered. The impact of cell death kinetics and re-oxygenation on tumour responses is illustrated for two radiotherapy fractionation schemes: a conventional schedule, and a hypofractionated treatment. The results show large differences in the doses needed to achieve 50% tumour control for the investigated cell death models. Moreover, the models affect the tumour responses differently depending on the treatment schedule. This corroborates the complex nature of re-oxygenation, showing the need to take into account the kinetics of cell death in radiation response models. (paper)

  9. Global model simulations of the impact of ocean-going ships on aerosols, clouds, and the radiation budget

    A. Lauer

    2007-10-01

    Full Text Available International shipping contributes significantly to the fuel consumption of all transport related activities. Specific emissions of pollutants such as sulfur dioxide (SO2 per kg of fuel emitted are higher than for road transport or aviation. Besides gaseous pollutants, ships also emit various types of particulate matter. The aerosol impacts the Earth's radiation budget directly by scattering and absorbing the solar and thermal radiation and indirectly by changing cloud properties. Here we use ECHAM5/MESSy1-MADE, a global climate model with detailed aerosol and cloud microphysics to study the climate impacts of international shipping. The simulations show that emissions from ships significantly increase the cloud droplet number concentration of low marine water clouds by up to 5% to 30% depending on the ship emission inventory and the geographic region. Whereas the cloud liquid water content remains nearly unchanged in these simulations, effective radii of cloud droplets decrease, leading to cloud optical thickness increase of up to 5–10%. The sensitivity of the results is estimated by using three different emission inventories for present-day conditions. The sensitivity analysis reveals that shipping contributes to 2.3% to 3.6% of the total sulfate burden and 0.4% to 1.4% to the total black carbon burden in the year 2000 on the global mean. In addition to changes in aerosol chemical composition, shipping increases the aerosol number concentration, e.g. up to 25% in the size range of the accumulation mode (typically >0.1 μm over the Atlantic. The total aerosol optical thickness over the Indian Ocean, the Gulf of Mexico and the Northeastern Pacific increases by up to 8–10% depending on the emission inventory. Changes in aerosol optical thickness caused by shipping induced modification of aerosol particle number concentration and chemical composition lead to a change in the shortwave radiation budget at the top of the

  10. Estimativas das componentes da radiação solar incidente em superfícies inclinadas baseadas na radiação global horizontal Estimates of solar radiation components on a tilted surface based on global horizontal radiation

    Adilson P. Souza

    2011-03-01

    Full Text Available Foram avaliadas equações estatísticas de estimativas com agrupamentos de dados anuais e mensais e suas respectivas validações, para as componentes global, direta e difusa da radiação solar incidente em superfícies inclinadas a 12,85, 22,85 e 32,85º, com face para o Norte, nas condições climáticas e geográficas de Botucatu, SP. Empregou-se as frações das três componentes da radiação a do topo da atmosfera em correlação com o coeficiente de transmissividade atmosférica do plano horizontal, em uma base de dados de abril/1998 a dezembro/2007, cujas medidas nas três inclinações ocorreram em diferentes períodos, todavia concomitantes ao plano horizontal. O aumento do ângulo de inclinação da superfície propiciou aumento do espalhamento dos valores diários do índice de claridade para superfícies inclinada e horizontal. Nos agrupamentos anuais os piores desempenhos foram verificados na estimativa da radiação difusa diária para superfície inclinada, com valores máximos de espalhamentos iguais a 3,89 MJ m-2 d-1 (43,65% e ajustamento em torno de 62%. Na estimativa das componentes global e direta da radiação solar nos planos inclinados, podem ser aplicadas, tanto as equações anuais como as mensais, com desempenhos dependentes das condições climáticas.Statistics equations and validations with groups of annual and monthly data were evaluated for global, direct and diffuse solar radiation components incident on the tilted surface to 12.85, 22.85 and 32.85° with the face North, in climate and geographical conditions of Botucatu, SP. It was employed the fractions of three components of extraterrestrial radiation in correlation with the coefficient clearness index horizontal plane, in a database of April/1998 to December/2007, whose measures at different periods in three inclinations, however concomitant to the horizontal plane. Increasing the angle of the surface led to increased scattering of the daily values of

  11. Global Strategy

    Li, Peter Ping

    2013-01-01

    Global strategy differs from domestic strategy in terms of content and process as well as context and structure. The content of global strategy can contain five key elements, while the process of global strategy can have six major stages. These are expounded below. Global strategy is influenced...... by rich and complementary local contexts with diverse resource pools and game rules at the national level to form a broad ecosystem at the global level. Further, global strategy dictates the interaction or balance between different entry strategies at the levels of internal and external networks....

  12. Energy and entropy balance for a black piecewise homogeneous planet

    Pollarolo, G.; Sertorio, L.

    1979-01-01

    In this paper a crude model for a planet interacting with the solar radiation is presented, the aim being the discussion of the global energy balance and corresponding entropy production. It is found that the power of the surface energy circulation and the temperature excursion have a peculiar nonlinear behaviour as a function of the parameters representing the specific heat of each piece and the thermal conductivity of their boundaries. (author)

  13. Balancing beyond the horizon?

    Kluth, Michael Friederich; Pilegaard, Jess

    2011-01-01

    The present article seeks to make sense of recent European Union (EU) naval capability changes by applying neo-realist theory to the EU as a collective actor in the global balance of power. The paper compares two different strands of neorealist theory by deducing key predictions about the expecte......-term balancing strategy aimed at bolstering the autonomy and international influence of the Union vis-a`-vis other major powers, including the USA....

  14. Aerosol influence on energy balance of the middle atmosphere of Jupiter.

    Zhang, Xi; West, Robert A; Irwin, Patrick G J; Nixon, Conor A; Yung, Yuk L

    2015-12-22

    Aerosols are ubiquitous in planetary atmospheres in the Solar System. However, radiative forcing on Jupiter has traditionally been attributed to solar heating and infrared cooling of gaseous constituents only, while the significance of aerosol radiative effects has been a long-standing controversy. Here we show, based on observations from the NASA spacecraft Voyager and Cassini, that gases alone cannot maintain the global energy balance in the middle atmosphere of Jupiter. Instead, a thick aerosol layer consisting of fluffy, fractal aggregate particles produced by photochemistry and auroral chemistry dominates the stratospheric radiative heating at middle and high latitudes, exceeding the local gas heating rate by a factor of 5-10. On a global average, aerosol heating is comparable to the gas contribution and aerosol cooling is more important than previously thought. We argue that fractal aggregate particles may also have a significant role in controlling the atmospheric radiative energy balance on other planets, as on Jupiter.

  15. Estimativa da radiação solar global a partir dos dados de insolação, para Santa Maria - RS Estimation of global radiation from insolation data for Santa Maria, RS, Brazil

    Galileo Adeli Buriol

    2012-09-01

    Full Text Available Foram determinados os coeficientes a e b da equação de Angströn-Prescott para a estimativa da radiação solar global para Santa Maria, RS. Utilizaram-se os dados diários da intensidade de fluxo de radiação solar global e de insolação (brilho solar registrados na Estação Meteorológica pertencente ao 8° Distrito de Meteorologia, localizada no Campus da Universidade Federal de Santa Maria - UFSM, período 2002-2008. Os dados foram copiados no banco de dados do 8° Distrito de Meteorologia - 8° DISME, em Porto Alegre, e calculados os valores diários de radiação solar global no topo da atmosfera e de insolação máxima possível, considerando a latitude local. Com esses dados, foram determinadas as equações mensais e estacionais de regressão para a estimativa da radiação solar global em função da insolação. Constatou-se que existe alta correlação entre os dados de radiação solar global com aqueles de insolação, sendo, assim, possível estimar a radiação solar global em função da insolação.Coefficients a and b of the Angströn - Prescott equation to estimate global solar radiation for Santa Maria, RS were determined. Daily data of global solar radiation and sunshine, were obtained from the Meteorological Station which belongs to the 8th District of Meteorology, located on the campus of the Federal University of Santa Maria - UFSM, period from 2002 to 2008. The mentioned data were copied from the database of the 8th District of Meteorology - 8th DISME in Porto Alegre. Top of atmosphere radiation and possible maximum sunshine were calculated considering local latitude. With such elements, monthly regression equations were determined for the estimation of solar radiation as a function of insolation. We found a high correlation between insolation and global solar radiation and it's possible to estimate the solar radiation depending on the measured insolation.

  16. Trends of the global radiation and sunshine hours in 1961-1998 and their relationships in China

    Chen Rensheng; Kang Ersi; Ji Xibin; Yang Jianping; Zhang Zhihui

    2006-01-01

    Trends of the yearly global radiation E g , annual sunshine hours S, yearly precipitation P and yearly averaged air temperature T at 51 stations in 1961-1998 in China were detected, and the significance test method was the F-test. A total of 47 stations showed decreasing trend in the E g series of which 35 passed the F-test at the 5% significant level. At 42 stations, the trend of S was also decreasing, and 36 of them passed the F-test at the 5% significant level. The P series did not change largely in 1961-1998 and at 37 stations showed a positive trend, while the positive trend or reduced trend at 39 stations did not pass the F-test at the 25% significant level. The positive trend of the T series was shown at 49 stations, of which 29 passed the F-test at the 1% significant level. In the yearly scale, the empirical relationship between E g and S at any station was very low because the length of the E g series was too short. When using all the data at the used 51 stations together to simulate E g , the results were good. Using the longitude λ, latitude φ and altitude H, or/and P and T, of the used stations to adjust the parameters a and b of the Angstroem model, respectively, or just to adjust the parameter a, the results will be better. The parameter b of the Angstroem model was little affected by the geographical position of the used stations. At last, a simple equation is recommended to use for simulation of the yearly global radiation in China

  17. Estimation of the daily global solar radiation based on the Gaussian process regression methodology in the Saharan climate

    Guermoui, Mawloud; Gairaa, Kacem; Rabehi, Abdelaziz; Djafer, Djelloul; Benkaciali, Said

    2018-06-01

    Accurate estimation of solar radiation is the major concern in renewable energy applications. Over the past few years, a lot of machine learning paradigms have been proposed in order to improve the estimation performances, mostly based on artificial neural networks, fuzzy logic, support vector machine and adaptive neuro-fuzzy inference system. The aim of this work is the prediction of the daily global solar radiation, received on a horizontal surface through the Gaussian process regression (GPR) methodology. A case study of Ghardaïa region (Algeria) has been used in order to validate the above methodology. In fact, several combinations have been tested; it was found that, GPR-model based on sunshine duration, minimum air temperature and relative humidity gives the best results in term of mean absolute bias error (MBE), root mean square error (RMSE), relative mean square error (rRMSE), and correlation coefficient ( r) . The obtained values of these indicators are 0.67 MJ/m2, 1.15 MJ/m2, 5.2%, and 98.42%, respectively.

  18. Forecasting method for global radiation time series without training phase: Comparison with other well-known prediction methodologies

    Voyant, Cyril; Motte, Fabrice; Fouilloy, Alexis; Notton, Gilles; Paoli, Christophe; Nivet, Marie-Laure

    2017-01-01

    Integration of unpredictable renewable energy sources into electrical networks intensifies the complexity of the grid management due to their intermittent and unforeseeable nature. Because of the strong increase of solar power generation the prediction of solar yields becomes more and more important. Electrical operators need an estimation of the future production. For nowcasting and short term forecasting, the usual technics based on machine learning need large historical data sets of good quality during the training phase of predictors. However data are not always available and induce an advanced maintenance of meteorological stations, making the method inapplicable for poor instrumented or isolated sites. In this work, we propose intuitive methodologies based on the Kalman filter use (also known as linear quadratic estimation), able to predict a global radiation time series without the need of historical data. The accuracy of these methods is compared to other classical data driven methods, for different horizons of prediction and time steps. The proposed approach shows interesting capabilities allowing to improve quasi-systematically the prediction. For one to 10 h horizons Kalman model performances are competitive in comparison to more sophisticated models such as ANN which require both consistent historical data sets and computational resources. - Highlights: • Solar radiation forecasting with time series formalism. • Trainless approach compared to machine learning methods. • Very simple method dedicated to solar irradiation forecasting with high accuracy.

  19. Occupational radiation exposure in PWR: International comparison of some global indicators between 1975 and 1985

    Lochard, J.; Benedittini, M.

    1987-09-01

    This report presents the main results of an international comparative study of occupational radiation exposure in Pressurised Water Reactors (PWRs). The comparison is based on some synthetic indicators concerning both collective and mean individual exposures assessed for the following countries: Belgium, United-States, France, Japan, Federal Republic of Germany, Sweden and Switzerland. Information has been gained from the published literature and when it was possible, through direct correspondence with power station operators or national regulatory authorities. It concerns 120 reactors totalizing more than 900 reactor operating years. For the comparison, only reactors which were installed after 1974 have been considered, in order to have more homogeneous data representative of modern operating plants. Indicators calculated for the comparison are the collective and mean individual doses per reactor expressed either on a calendar year basis (from 1975 to 1985) or on a number of operating year basis (up to 11 years) [fr

  20. A "Fine Balance" in Truth and Fiction: Exploring Globalization's Impacts on Community and Implications for Adult Learning in Rohinton Mistry's Novel and Related Literature

    Jubas, Kaela

    2005-01-01

    Globalization continues to interest researchers and practitioners as it unfolds around us. This article contributes to the analysis of globalization's discourse, objectives and outcomes, by exploring the impact of globalization on community and its implications for adult learning. Using selected themes from a work of fiction to frame this…

  1. Development of multi-sensor global cloud and radiance composites for earth radiation budget monitoring from DSCOVR

    Khlopenkov, Konstantin; Duda, David; Thieman, Mandana; Minnis, Patrick; Su, Wenying; Bedka, Kristopher

    2017-10-01

    The Deep Space Climate Observatory (DSCOVR) enables analysis of the daytime Earth radiation budget via the onboard Earth Polychromatic Imaging Camera (EPIC) and National Institute of Standards and Technology Advanced Radiometer (NISTAR). Radiance observations and cloud property retrievals from low earth orbit and geostationary satellite imagers have to be co-located with EPIC pixels to provide scene identification in order to select anisotropic directional models needed to calculate shortwave and longwave fluxes. A new algorithm is proposed for optimal merging of selected radiances and cloud properties derived from multiple satellite imagers to obtain seamless global hourly composites at 5-km resolution. An aggregated rating is employed to incorporate several factors and to select the best observation at the time nearest to the EPIC measurement. Spatial accuracy is improved using inverse mapping with gradient search during reprojection and bicubic interpolation for pixel resampling. The composite data are subsequently remapped into EPIC-view domain by convolving composite pixels with the EPIC point spread function defined with a half-pixel accuracy. PSF-weighted average radiances and cloud properties are computed separately for each cloud phase. The algorithm has demonstrated contiguous global coverage for any requested time of day with a temporal lag of under 2 hours in over 95% of the globe.

  2. Determination of the water use and water use response of canola to solar radiation and temperature by using heat balance stem flow gauges

    Angadi, S.V.; Cutforth, H.W.; McConkey, B.G.

    2003-01-01

    Sap flow gauges using a heat balance have been reliable for measuring real-time transpiration in a number of crops. However, information on the accuracy of sap flow gauges in canola is lacking. Therefore, a study was conducted to validate the sap flow system in canola and to observe sap flow response to variations in temperature and solar radiation. There were strong relationships between sap flow measured with sap flow gauges and actual transpiration measured by the gravimetric method over short periods of 1 h (r 2 = 0.93 and RMSE = 2.34 g h -1 ), and over longer periods of 1 d (r 2 0.83 and RMSE = 48 g d -1 ), although sap flow slightly overestimated transpiration. In both cases the slope was not significantly different from 1. Water use in canola, estimated with sap flow gauges or from actual transpiration measurement, was dependent upon temperature (r 2 = 0.94 to 0.96). Water use increased until daytime temperatures reached 36 o C, after which water use decreased. Sap flow followed solar radiation trends in the field. Heat is lost or dissipated from the gauges convectively as the sap flows through the stem, conductively through the solid stem material, and radially into the surrounding air. As the convective proportion of the heat loss from the gauge increased, the accuracy of the water use estimation using the sap flow gauges increased. For sunny days, convective heat loss through sap flow accounted for a major portion of the total heat input to the gauges, while on cloudy days radial heat loss from the gauges accounted for a, major portion of the heat input. Thus, at low sap flow rates during cloudy days, the possibility of error in the sap flow system was high. Overall, sap flow in canola was strongly related to daily solar radiation (r 2 = 0.92). The sensitive response to weather variations and the possibility of improving the accuracy at high flow rates in the field makes the use of sap flow gauges a viable option for measuring real-time transpiration in

  3. Mechanisms of Formation of Secondary Organic Aerosols and Implications for Global Radiative Forcing

    Seinfeld, John H. [California Inst. of Technology (CalTech), Pasadena, CA (United States)

    2011-12-02

    Organic material constitutes about 50% of global atmospheric aerosol mass, and the dominant source of organic aerosol is the oxidation of volatile hydrocarbons, to produce secondary organic aerosol (SOA). Understanding the formation of SOA is crucial to predicting present and future climate effects of atmospheric aerosols. The goal of this program is to significantly increase our understanding of secondary organic aerosol (SOA) formation in the atmosphere. Ambient measurements indicate that the amount of SOA in the atmosphere exceeds that predicted in current models based on existing laboratory chamber data. This would suggest that either the SOA yields measured in laboratory chambers are understated or that all major organic precursors have not been identified. In this research program we are systematically exploring these possibilities.

  4. Long range global warming

    Rolle, K.C.; Pulkrabek, W.W.; Fiedler, R.A.

    1995-01-01

    This paper explores one of the causes of global warming that is often overlooked, the direct heating of the environment by engineering systems. Most research and studies of global warming concentrate on the modification that is occurring to atmospheric air as a result of pollution gases being added by various systems; i.e., refrigerants, nitrogen oxides, ozone, hydrocarbons, halon, and others. This modification affects the thermal radiation balance between earth, sun and space, resulting in a decrease of radiation outflow and a slow rise in the earth's steady state temperature. For this reason the solution to the problem is perceived as one of cleaning up the processes and effluents that are discharged into the environment. In this paper arguments are presented that suggest, that there is a far more serious cause for global warming that will manifest itself in the next two or three centuries; direct heating from the exponential growth of energy usage by humankind. Because this is a minor contributor to the global warming problem at present, it is overlooked or ignored. Energy use from the combustion of fuels and from the output of nuclear reactions eventually is manifest as warming of the surroundings. Thus, as energy is used at an ever increasing rate the consequent global warming also increases at an ever increasing rate. Eventually this rate will become equal to a few percent of solar radiation. When this happens the earth's temperature will have risen by several degrees with catastrophic results. The trends in world energy use are reviewed and some mathematical models are presented to suggest future scenarios. These models can be used to predict when the global warming problem will become undeniably apparent, when it will become critical, and when it will become catastrophic

  5. Global Pattern of Nasopharyngeal Cancer: Correlation of Outcome With Access to Radiation Therapy

    Lam, Ka-On [Clinical Oncology Center, University of Hong Kong-Shenzhen Hospital, Shenzhen (China); Lee, Anne W.M., E-mail: annelee@hku-szh.org [Clinical Oncology Center, University of Hong Kong-Shenzhen Hospital, Shenzhen (China); Choi, Cheuk-Wai [Department of Systems Engineering and Engineering Management, City University of Hong Kong, Hong Kong (China); Sze, Henry C.K. [Clinical Oncology Center, University of Hong Kong-Shenzhen Hospital, Shenzhen (China); Zietman, Anthony L. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Hopkins, Kirsten I.; Rosenblatt, Eduardo [International Atomic Energy Agency, Vienna (Austria)

    2016-04-01

    Purpose: This study aimed to estimate the treatment outcome of nasopharyngeal cancer (NPC) across the world and its correlation with access to radiation therapy (RT). Methods and Materials: The age-standardized mortality (ASM) and age-standardized incidence (ASI) rates of NPC from GLOBOCAN (2012) were summarized, and [1−(ASM/ASI)] was computed to give the proxy relative survival (RS). Data from the International Atomic Energy Agency (IAEA) and the World Bank were used to assess the availability of RT in surrogate terms: the number of RT equipment units and radiation oncologists per million population. Results: A total of 112 countries with complete valid data were analyzed, and the proxy RS varied widely from 0% to 83% (median, 50%). Countries were categorized into Good, Median, and Poor outcome groups on the basis of their proxy RS (<45%, 45%-55%, and >55%). Eighty percent of new cases occurred in the Poor outcome group. Univariable linear regression showed a significant correlation between outcome and the availability of RT: proxy RS increased at 3.4% (P<.001) and 1.5% (P=.001) per unit increase in RT equipment and oncologist per million population, respectively. The median number of RT equipment units per million population increased significantly from 0.5 in the Poor, to 1.5 in the Median, to 4.6 in the Good outcome groups, and the corresponding number of oncologists increased from 1.1 to 3.3 to 7.1 (P<.001). Conclusions: Nasopharyngeal cancer is a highly treatable disease, but the outcome varies widely across the world. The current study shows a significant correlation between survival and access to RT based on available surrogate indicators. However, the possible reasons for poor outcome are likely to be multifactorial and complex. Concerted international efforts are needed not only to address the fundamental requirement for adequate RT access but also to obtain more comprehensive and accurate data for research to improve cancer outcome.

  6. Predictive spatio-temporal model for spatially sparse global solar radiation data

    André, Maïna; Dabo-Niang, Sophie; Soubdhan, Ted; Ould-Baba, Hanany

    2016-01-01

    This paper introduces a new approach for the forecasting of solar radiation series at a located station for very short time scale. We built a multivariate model in using few stations (3 stations) separated with irregular distances from 26 km to 56 km. The proposed model is a spatio temporal vector autoregressive VAR model specifically designed for the analysis of spatially sparse spatio-temporal data. This model differs from classic linear models in using spatial and temporal parameters where the available predictors are the lagged values at each station. A spatial structure of stations is defined by the sequential introduction of predictors in the model. Moreover, an iterative strategy in the process of our model will select the necessary stations removing the uninteresting predictors and also selecting the optimal p-order. We studied the performance of this model. The metric error, the relative root mean squared error (rRMSE), is presented at different short time scales. Moreover, we compared the results of our model to simple and well known persistence model and those found in literature. - Highlights: • A spatio-temporal VAR forecast model is used for spatially sparse data solar. • Lags and locations are selected by an optimization strategy. • Definition of spatial ordering of predictors influences forecasting results. • The model shows a better performance predictive at 30 min ahead in our context. • Benchmarking study shows a more accurate forecast at 1 h ahead with spatio-temporal VAR.

  7. Quantitative Evaluation of MODIS Fire Radiative Power Measurement for Global Smoke Emissions Assessment

    Ichoku, Charles; Ellison, Luke

    2011-01-01

    Satellite remote sensing is providing us tremendous opportunities to measure the fire radiative energy (FRE) release rate or power (FRP) from open biomass burning, which affects many vegetated regions of the world on a seasonal basis. Knowledge of the biomass burning characteristics and emission source strengths of different (particulate and gaseous) smoke constituents is one of the principal ingredients upon which the assessment, modeling, and forecasting of their distribution and impacts depend. This knowledge can be gained through accurate measurement of FRP, which has been shown to have a direct relationship with the rates of biomass consumption and emissions of major smoke constituents. Over the last decade or so, FRP has been routinely measured from space by both the MODIS sensors aboard the polar orbiting Terra and Aqua satellites, and the SEVIRI sensor aboard the Meteosat Second Generation (MSG) geostationary satellite. During the last few years, FRP has steadily gained increasing recognition as an important parameter for facilitating the development of various scientific studies and applications relating to the quantitative characterization of biomass burning and their emissions. To establish the scientific integrity of the FRP as a stable quantity that can be measured consistently across a variety of sensors and platforms, with the potential of being utilized to develop a unified long-term climate data record of fire activity and impacts, it needs to be thoroughly evaluated, calibrated, and validated. Therefore, we are conducting a detailed analysis of the FRP products from MODIS to evaluate the uncertainties associated with them, such as those due to the effects of satellite variable observation geometry and other factors, in order to establish their error budget for use in diverse scientific research and applications. In this presentation, we will show recent results of the MODIS FRP uncertainty analysis and error mitigation solutions, and demonstrate

  8. Multi-GPU configuration of 4D intensity modulated radiation therapy inverse planning using global optimization

    Hagan, Aaron; Sawant, Amit; Folkerts, Michael; Modiri, Arezoo

    2018-01-01

    We report on the design, implementation and characterization of a multi-graphic processing unit (GPU) computational platform for higher-order optimization in radiotherapy treatment planning. In collaboration with a commercial vendor (Varian Medical Systems, Palo Alto, CA), a research prototype GPU-enabled Eclipse (V13.6) workstation was configured. The hardware consisted of dual 8-core Xeon processors, 256 GB RAM and four NVIDIA Tesla K80 general purpose GPUs. We demonstrate the utility of this platform for large radiotherapy optimization problems through the development and characterization of a parallelized particle swarm optimization (PSO) four dimensional (4D) intensity modulated radiation therapy (IMRT) technique. The PSO engine was coupled to the Eclipse treatment planning system via a vendor-provided scripting interface. Specific challenges addressed in this implementation were (i) data management and (ii) non-uniform memory access (NUMA). For the former, we alternated between parameters over which the computation process was parallelized. For the latter, we reduced the amount of data required to be transferred over the NUMA bridge. The datasets examined in this study were approximately 300 GB in size, including 4D computed tomography images, anatomical structure contours and dose deposition matrices. For evaluation, we created a 4D-IMRT treatment plan for one lung cancer patient and analyzed computation speed while varying several parameters (number of respiratory phases, GPUs, PSO particles, and data matrix sizes). The optimized 4D-IMRT plan enhanced sparing of organs at risk by an average reduction of 26% in maximum dose, compared to the clinical optimized IMRT plan, where the internal target volume was used. We validated our computation time analyses in two additional cases. The computation speed in our implementation did not monotonically increase with the number of GPUs. The optimal number of GPUs (five, in our study) is directly related to the

  9. Hourly forecasting of global solar radiation based on multiscale decomposition methods: A hybrid approach

    Monjoly, Stéphanie; André, Maïna; Calif, Rudy; Soubdhan, Ted

    2017-01-01

    This paper introduces a new approach for the forecasting of solar radiation series at 1 h ahead. We investigated on several techniques of multiscale decomposition of clear sky index K_c data such as Empirical Mode Decomposition (EMD), Ensemble Empirical Mode Decomposition (EEMD) and Wavelet Decomposition. From these differents methods, we built 11 decomposition components and 1 residu signal presenting different time scales. We performed classic forecasting models based on linear method (Autoregressive process AR) and a non linear method (Neural Network model). The choice of forecasting method is adaptative on the characteristic of each component. Hence, we proposed a modeling process which is built from a hybrid structure according to the defined flowchart. An analysis of predictive performances for solar forecasting from the different multiscale decompositions and forecast models is presented. From multiscale decomposition, the solar forecast accuracy is significantly improved, particularly using the wavelet decomposition method. Moreover, multistep forecasting with the proposed hybrid method resulted in additional improvement. For example, in terms of RMSE error, the obtained forecasting with the classical NN model is about 25.86%, this error decrease to 16.91% with the EMD-Hybrid Model, 14.06% with the EEMD-Hybid model and to 7.86% with the WD-Hybrid Model. - Highlights: • Hourly forecasting of GHI in tropical climate with many cloud formation processes. • Clear sky Index decomposition using three multiscale decomposition methods. • Combination of multiscale decomposition methods with AR-NN models to predict GHI. • Comparison of the proposed hybrid model with the classical models (AR, NN). • Best results using Wavelet-Hybrid model in comparison with classical models.

  10. Globally Stable Microresonator Turing Pattern Formation for Coherent High-Power THz Radiation On-Chip

    Huang, Shu-Wei; Yang, Jinghui; Yang, Shang-Hua; Yu, Mingbin; Kwong, Dim-Lee; Zelevinsky, T.; Jarrahi, Mona; Wong, Chee Wei

    2017-10-01

    In nonlinear microresonators driven by continuous-wave (cw) lasers, Turing patterns have been studied in the formalism of the Lugiato-Lefever equation with emphasis on their high coherence and exceptional robustness against perturbations. Destabilization of Turing patterns and the transition to spatiotemporal chaos, however, limit the available energy carried in the Turing rolls and prevent further harvest of their high coherence and robustness to noise. Here, we report a novel scheme to circumvent such destabilization, by incorporating the effect of local mode hybridizations, and we attain globally stable Turing pattern formation in chip-scale nonlinear oscillators with significantly enlarged parameter space, achieving a record-high power-conversion efficiency of 45% and an elevated peak-to-valley contrast of 100. The stationary Turing pattern is discretely tunable across 430 GHz on a THz carrier, with a fractional frequency sideband nonuniformity measured at 7.3 ×10-14 . We demonstrate the simultaneous microwave and optical coherence of the Turing rolls at different evolution stages through ultrafast optical correlation techniques. The free-running Turing-roll coherence, 9 kHz in 200 ms and 160 kHz in 20 minutes, is transferred onto a plasmonic photomixer for one of the highest-power THz coherent generations at room temperature, with 1.1% optical-to-THz power conversion. Its long-term stability can be further improved by more than 2 orders of magnitude, reaching an Allan deviation of 6 ×10-10 at 100 s, with a simple computer-aided slow feedback control. The demonstrated on-chip coherent high-power Turing-THz system is promising to find applications in astrophysics, medical imaging, and wireless communications.

  11. Spatio-Temporal Characteristics in the Clearness Index Derived from Global Solar Radiation Observations in Korea

    Yeonjin Jung

    2016-04-01

    Full Text Available The spatio-temporal characteristics of the clearness index (KT were investigated using daily global solar irradiance measurements (290–2800 nm for the period of 2000–2014 at 21 sites in Korea, a complex region in East Asia with a distinct monsoon season and heavy aerosol loading year-round. The annual mean KT value for all sites is 0.46, with values of 0.63 and 0.25 for clear and overcast skies, respectively. The seasonal variations in monthly average KT show a minimum of 0.37 in July at all sites except for Jeju, where the value was 0.29 in January. The maximum value (KT = 0.51 is observed in October, followed by a secondary peak (KT = 0.49 during February–April. The lowest KT value (KT = 0.42 was observed at both the Seoul and Jeju sites, and the highest (KT = 0.48 in the southeastern regions. Increases in average KT exceeding 4% per decade were observed in the middle and southeastern regions, with the maximum (+8% per decade at the Daegu site. Decreasing trends (<−4% per decade were observed in the southwestern regions, with the maximum (−7% per decade at the Mokpo site. Cloud amount, relative humidity, and aerosol optical depth together explained 57% of the variance in daily mean KT values. The contributions of these three variables to variations in KT are 42%, 9% and 6%, respectively. Thus, the variations in KT in Korea can be primarily attributed to the presence of clouds and water vapor, with relatively weak aerosol effects.

  12. Changing global carbon cycle

    Canadell, Pep

    2007-01-01

    Full text: The increase in atmospheric carbon dioxide (C02) is the single largest human perturbation on the earth's radiative balance contributing to climate change. Its rate of change reflects the balance between anthropogenic carbon emissions and the dynamics of a number of terrestrial and ocean processes that remove or emit C02. It is the long term evolution of this balance that will determine to large extent the speed and magnitude of the human induced climate change and the mitigation requirements to stabilise atmospheric C02 concentrations at any given level. In this talk, we show new trends in global carbon sources and sinks, with particularly focus on major shifts occurring since 2000 when the growth rate of atmospheric C02 has reached its highest level on record. The acceleration in the C02 growth results from the combination of several changes in properties of the carbon cycle, including: acceleration of anthropogenic carbon emissions; increased carbon intensity of the global economy, and decreased efficiency of natural carbon sinks. We discuss in more detail some of the possible causes of the reduced efficiency of natural carbon sinks on land and oceans, such as the decreased net sink in the Southern Ocean and on terrestrial mid-latitudes due to world-wide occurrence of drought. All these changes reported here characterise a carbon cycle that is generating stronger than expected climate forcing, and sooner than expected

  13. Comparative studies of measured and estimated values of global solar radiation using Eppley pyranometer and Hargreaves Samani-model at Nsukka under varying climatic conditions

    Anikpa, P.O.; Osuji, R.U.

    2005-12-01

    This study uses the Hargreaves and Samani (HS) modified model in estimating daily global solar radiation at Nsukka. The model equation was based on daily air temperature range and extraterrestrial solar radiation. The estimated results obtained for six months, staring from 25th August, 2003 to 20th February, 2004 were compared to measured values obtained with standard Eppley pyranometer. The measurements were taken manually within the same period. The comparison indicates that in the dry season months under consideration (December, 2003; January, 2004 and February, 2004) the model clearly gave higher insolation values of the daily global solar radiation. In the wet season months considered (i.e., part of August, 2003 through November, 2003) the model showed neither a clear pattern of higher nor a lower insolation. Further correlation analysis produced neither bias for the wet season nor dry season months. This indicates that on a monthly basis, the monthly average for estimated and measured values correlated well. (author)

  14. Radiations

    Pujol Mora, J.

    1999-01-01

    The exposition to ionizing radiations is a constant fact in the life of the human being and its utilization as diagnostic and therapeutic method is generalized. However, it is notorious how as years go on, the fear to the ionizing radiation seems to persist too, and this fact is not limited to the common individual, but to the technical personnel and professional personnel that labors with them same. (S. Grainger) [es

  15. Radiation

    Davidson, J.H.

    1986-01-01

    The basic facts about radiation are explained, along with some simple and natural ways of combating its ill-effects, based on ancient healing wisdom as well as the latest biochemical and technological research. Details are also given of the diet that saved thousands of lives in Nagasaki after the Atomic bomb attack. Special comment is made on the use of radiation for food processing. (U.K.)

  16. Bridging Innovation and Outreach to Overcome Global Gaps in Radiation Oncology Through Information and Communication Tools, Trainee Advancement, Engaging Industry, Attention to Ethical Challenges, and Political Advocacy.

    Dad, Luqman; Royce, Trevor J; Morris, Zachary; Moran, Meena; Pawlicki, Todd; Khuntia, Deepak; Hardenbergh, Patricia; Cummings, Bernard; Mayr, Nina; Hu, Kenneth

    2017-04-01

    An evolving paradigm in global outreach in radiation oncology has been the implementation of a more region-specific, needs-based approach to help close the gap in radiation services to low- and middle-income countries through the use of innovative tools in information and communication technology. This report highlights 4 information and communication technology tools in action today: (1) the NCCN Framework for Resource Stratification of NCCN guidelines, (2) ASTRO e-Contouring, (3) i.treatsafely.org, and (4) ChartRounds.com. We also render special consideration to matters related to global outreach that we believe require distinct attention to help us meet the goals established by the 2011 United Nations׳ Declaration on noncommunicable diseases: (1) trainee advancement toward careers in global health, (2) ethical challenges of international outreach, (3) critical importance of political advocacy, and (4) collaboration with Industry. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Variability and trends of downward surface global solar radiation over the Iberian Peninsula based on ERA-40 reanalysis

    Perdigão, João Carlos

    2016-01-26

    © 2016 Royal Meteorological Society. A climate study of the incidence of downward surface global solar radiation (SSRD) in the Iberian Peninsula (IP) based primarily on ERA-40 reanalysis is presented. NCEP/NCAR reanalysis and ground-based records from several Portuguese and Spanish stations have been also considered. The results show that reanalysis can capture a similar inter-annual variability as compared to ground-based observations, especially on a monthly basis, even though annual ERA-40 (NCEP/NCAR) values tend to underestimate (overestimate) the observations with a mean relative difference of around 20Wm-2 (40Wm-2). On the other hand, ground-based measurements in Portuguese stations during the period 1964-1989 show a tendency to decrease until the mid-1970s followed by an increase up to the end of the study period, in line with the dimming/brightening phenomenon reported in the literature. Nevertheless, there are different temporal behaviours as a greater increase since the 1970s is observed in the south and less industrialized regions. Similarly, the ERA-40 reanalysis shows a noticeable decrease until the early 1970s followed by a slight increase up to the end of the 1990s, suggesting a dimming/brightening transition around the early 1970s, earlier in the south and centre and later in the north of the IP. Although there are slight differences in the magnitude of the trends as well as the turning year of the dimming/brightening periods, the decadal changes of ERA-40 fairly agree with the ground-based observations in Portugal and Spain, in contrast to most of the literature for other regions of the world, and is used in the climatology of the SSRD in the study area. NCEP/NCAR reanalysis does not capture the decadal variations of SSRD in the IP. The results show that part of the decadal variability of the global radiation in the IP is related to changes in cloud cover (represented in ERA-40).

  18. Variability and trends of downward surface global solar radiation over the Iberian Peninsula based on ERA-40 reanalysis

    Perdigã o, Joã o Carlos; Salgado, Rui; Costa, Maria Joã o; Dasari, Hari Prasad; Sanchez-Lorenzo, Arturo

    2016-01-01

    © 2016 Royal Meteorological Society. A climate study of the incidence of downward surface global solar radiation (SSRD) in the Iberian Peninsula (IP) based primarily on ERA-40 reanalysis is presented. NCEP/NCAR reanalysis and ground-based records from several Portuguese and Spanish stations have been also considered. The results show that reanalysis can capture a similar inter-annual variability as compared to ground-based observations, especially on a monthly basis, even though annual ERA-40 (NCEP/NCAR) values tend to underestimate (overestimate) the observations with a mean relative difference of around 20Wm-2 (40Wm-2). On the other hand, ground-based measurements in Portuguese stations during the period 1964-1989 show a tendency to decrease until the mid-1970s followed by an increase up to the end of the study period, in line with the dimming/brightening phenomenon reported in the literature. Nevertheless, there are different temporal behaviours as a greater increase since the 1970s is observed in the south and less industrialized regions. Similarly, the ERA-40 reanalysis shows a noticeable decrease until the early 1970s followed by a slight increase up to the end of the 1990s, suggesting a dimming/brightening transition around the early 1970s, earlier in the south and centre and later in the north of the IP. Although there are slight differences in the magnitude of the trends as well as the turning year of the dimming/brightening periods, the decadal changes of ERA-40 fairly agree with the ground-based observations in Portugal and Spain, in contrast to most of the literature for other regions of the world, and is used in the climatology of the SSRD in the study area. NCEP/NCAR reanalysis does not capture the decadal variations of SSRD in the IP. The results show that part of the decadal variability of the global radiation in the IP is related to changes in cloud cover (represented in ERA-40).

  19. Radiation

    Winther, J.F.; Ulbak, K.; Dreyer, L.; Pukkala, E.; Oesterlind, A.

    1997-01-01

    Exposure to solar and ionizing radiation increases the risk for cancer in humans. Some 5% of solar radiation is within the ultraviolet spectrum and may cause both malignant melanoma and non-melanocytic skin cancer; the latter is regarded as a benign disease and is accordingly not included in our estimation of avoidable cancers. Under the assumption that the rate of occurrence of malignant melanoma of the buttocks of both men and women and of the scalp of women would apply to all parts of the body in people completely unexposed to solar radiation, it was estimated that approximately 95% of all malignant melanomas arising in the Nordic populations around the year 2000 will be due to exposure to natural ultraviolet radiation, equivalent to an annual number of about 4700 cases, with 2100 in men and 2600 in women, or some 4% of all cancers notified. Exposure to ionizing radiation in the Nordic countries occurs at an average effective dose per capita per year of about 3 mSv (Iceland, 1.1 mSv) from natural sources, and about 1 mSv from man-made sources. While the natural sources are primarily radon in indoor air, natural radionuclides in food, cosmic radiation and gamma radiation from soil and building materials, the man-made sources are dominated by the diagnostic and therapeutic use of ionizing radiation. On the basis of measured levels of radon in Nordic dwellings and associated risk estimates for lung cancer derived from well-conducted epidemiological studies, we estimated that about 180 cases of lung cancer (1% of all lung cancer cases) per year could be avoided in the Nordic countries around the year 2000 if indoor exposure to radon were eliminated, and that an additional 720 cases (6%) could be avoided annually if either radon or tobacco smoking were eliminated. Similarly, it was estimated that the exposure of the Nordic populations to natural sources of ionizing radiation other than radon and to medical sources will each give rise to an annual total of 2120

  20. Balancing Audio

    Walther-Hansen, Mads

    2016-01-01

    is not thoroughly understood. In this paper I treat balance as a metaphor that we use to reason about several different actions in music production, such as adjusting levels, editing the frequency spectrum or the spatiality of the recording. This study is based on an exploration of a linguistic corpus of sound......This paper explores the concept of balance in music production and examines the role of conceptual metaphors in reasoning about audio editing. Balance may be the most central concept in record production, however, the way we cognitively understand and respond meaningfully to a mix requiring balance...

  1. Radiative efficiencies and global warming potentials using theoretically determined absorption cross-sections for several hydrofluoroethers (HFEs) and hydrofluoropolyethers (HFPEs)

    Bravo, Ivan; Marston, George; Nutt, David R.; Shine, Keith P.

    2011-01-01

    Integrated infrared cross-sections and wavenumber positions for the vibrational modes of a range of hydrofluoroethers (HFEs) and hydrofluoropolyethers (HFPEs) have been calculated. Spectra were determined using a density functional method with an empirically derived correction for the wavenumbers of band positions. Radiative efficiencies (REs) were determined using the Pinnock et al. method and were used with atmospheric lifetimes from the literature to determine global warming potentials (GWPs). For the HFEs and the majority of the molecules in the HG series HFPEs, theoretically determined absorption cross-sections and REs lie within ca. 10% of those determined using measured spectra. For the larger molecules in the HG series and the HG' series of HFPEs, agreement is less good, with theoretical values for the integrated cross-sections being up to 35% higher than the experimental values; REs are up to 45% higher. Our method gives better results than previous theoretical approaches, because of the level of theory chosen and, for REs, because an empirical wavenumber correction derived for perfluorocarbons is effective in predicting the positions of C-F stretching frequencies at around 1250 cm -1 for the molecules considered here.

  2. Balancing Act

    Part of being an Active, More Powerful You means finding balance in your daily life: taking on the Must-dos and finding time for some Should Dos and Want-to-Dos. Sometimes, emotions and commitments can come into play and upset the balance.

  3. Balanced sampling

    Brus, D.J.

    2015-01-01

    In balanced sampling a linear relation between the soil property of interest and one or more covariates with known means is exploited in selecting the sampling locations. Recent developments make this sampling design attractive for statistical soil surveys. This paper introduces balanced sampling

  4. Getting the balance right

    1987-01-01

    This 8 page leaflet is published by the Nuclear Electricity Information Group (NEIG) which is made up of eight different bodies working within the nuclear industry. It aims to present a balanced outline of the facts needed to form an opinion about energy policy in the UK. It looks at the price of electricity, other sources of electricity, (oil and coal, solar power, wind power, water power), safety in the nuclear industry, nuclear waste disposal and risks from radiation. The NEIG is in favour of a balanced energy programme with nuclear energy being only a part of the overall scheme. (U.K.)

  5. Thinking globally and acting locally in Mindanao: Supporting the delicate balance of future sustainability in South-East Asian wilderness as well as rural areas

    Richards, C

    2014-01-01

    Although models of future sustainability often talk about effectively balancing economic, social and environmental imperatives or factors, in practice this typically remains an elusive ideal. This paper explores the exemplary possibilities but also dilemmas of a proposed initiative in the resource-rich but under-developed Filippino island province of Mindanao to achieve such a delicate balance in practice. This initiative by Raintrust Sustainable Ventures' proposes to link foreign investment in agricultural development to both the social advancement of local tribal peoples and the protection of large amounts of remaining wilderness areas. Such a case study provides an exemplary basis for discussing the challenge of achieving social and environmental as well as economic domains of 'future sustainability'. The crucial supporting role of information and geospatial technologies in the Raintrust plan will also be discussed

  6. Diffuse solar radiation and associated meteorological parameters in India

    A. B. Bhattacharya

    Full Text Available Solar diffuse radiation data including global radiation, shortwave and longwave balances, net radiation and sunshine hours have been extensively analyzed to study the variation of diffuse radiation with turbidity and cloud discharges appearing in the form of atmospherics over the tropics. Results of surface radiation measurements at Calcutta, Poona, Delhi and Madras are presented together with some meteorological parameters. The monthly values of diffuse radiation and the monthly ratios of diffuse to global solar radiation have been examined, with a special emphasis in relation to the noise level of atmospherics at Calcutta in the very low frequency band. The results exhibit some definite seasonal changes which appear to be in close agreement with one another.

  7. Present and potential future contributions of sulfate, black and organic carbon aerosols from China to global air quality, premature mortality and radiative forcing

    Saikawa, Eri; Naik, Vaishali; Horowitz, Larry W.; Liu, Junfeng; Mauzerall, Denise L.

    Aerosols are harmful to human health and have both direct and indirect effects on climate. China is a major contributor to global emissions of sulfur dioxide (SO 2), a sulfate (SO 42-) precursor, organic carbon (OC), and black carbon (BC) aerosols. Although increasingly examined, the effect of present and potential future levels of these emissions on global premature mortality and climate change has not been well quantified. Through both direct radiative effects and indirect effects on clouds, SO 42- and OC exert negative radiative forcing (cooling) while BC exerts positive forcing (warming). We analyze the effect of China's emissions of SO 2, SO 42-, OC and BC in 2000 and for three emission scenarios in 2030 on global surface aerosol concentrations, premature mortality, and radiative forcing (RF). Using global models of chemical transport (MOZART-2) and radiative transfer (GFDL RTM), and combining simulation results with gridded population data, mortality rates, and concentration-response relationships from the epidemiological literature, we estimate the contribution of Chinese aerosols to global annual premature mortality and to RF in 2000 and 2030. In 2000, we estimate these aerosols cause approximately 470 000 premature deaths in China and an additional 30 000 deaths globally. In 2030, aggressive emission controls lead to a 50% reduction in premature deaths from the 2000 level to 240 000 in China and 10 000 elsewhere, while under a high emissions scenario premature deaths increase 50% from the 2000 level to 720 000 in China and to 40 000 elsewhere. Because the negative RF from SO 42- and OC is larger than the positive forcing from BC, Chinese aerosols lead to global net direct RF of -74 mW m -2 in 2000 and between -15 and -97 mW m -2 in 2030 depending on the emissions scenario. Our analysis indicates that increased effort to reduce greenhouse gases is essential to address climate change as China's anticipated reduction of aerosols will result in the

  8. In the balance

    Kluth, Michael Friederich; Pilegaard, Jess

    The present paper seeks to make sense of recent EU naval capability changes by applying neo-realist theory on the EU as an international actor in the global balance of power. The paper compares three different strands of Neo-realist theory by deducting key predictions about the expected defense...... posture of the Union and the expected changes in naval capabilities. The