Importance Of Solar Radiation Research Articles

The University of West Florida Campus Ecosystem Study: effects of forest vegetation on light availability and soil processes.

College and university campuses with a notable arboreal component provide unique opportunities for carrying out ecological research. The University of West Florida Campus Ecosystem Study (UWF CES) was established in 2019 as interconnected research to take advantage of the extensive arborescent nature of the UWF campus, particularly concerning longleaf pine (Pinus palustris). One of these investigations established permanent plots in forested sites of two contrasting types, one dominated by longleaf pine ("pine site") and the other dominated by hardwoods ('hardwood site'). This study used these plots to examine the influence of forest vegetation on light availability and soil processes. Light was measured as photosynthetically active radiation (and expressed as photon flux density-PFD) with a handheld meter in each plot. Soil was sampled to 5 cm in each plot; texture was measured with the hydrometer method. Identical sampling methods were carried out in a persistent canopy opening to assess light and soil conditions under maximum solar radiation. Mean PFD was ~4× higher in pine stands than in hardwood stands; PFD was 12.8 and 3.5% of full light in the pine and hardwood stands, respectively. All soils were dominated by coarse-textured sands, but silt was significantly higher in pine stand soil and higher still in the canopy opening. Among forest stand plots, sand was negatively related to PFD, whereas clay was positively related to PFD. Across the three sites, silt was positively related to PFD. These relationships are consistent with the importance of solar radiation as one of many drivers of soil weathering.

Importance of solar radiation and the need for improved respect to Sun by Agrometeorologists

Solar radiation refers to energy produced by the Sun, some of which reaches the Earth. This is the primary energy source for most processes in the atmosphere, hydrosphere, and biosphere. Solar radiation is of crucial importance inproviding the energy source for photosynthesis. During 1973 to 1977, when I did my Ph.D. in Agroclimatology in the Iowa State University, USA, I conducted the field experiments during 1975 and 1976 on soil-plant-water relations, growth and nutrient uptake patterns of field grown soybeans under water stress at the Western Iowa Experimental Farm, Castana. During these experiments, the solar radiation was measured with a pyranometer sensor mounted on an anodized aluminimum base. Daily solar radiation values were obtained from an LI-500 integrator attached to the pyranometer sensor. The attenuation of photosynthetically active radiation (PAR) and net radiation (NRAD) in the soybean canopy was determined during the growing season by using vertical profiles of radiation and leaf-area-index values. Once I received my Ph.D., I worked at the Headquarters of the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) in Hyderabad from 1977 to 1983 and at the ICRISAT Sahelian Center, Niamey, Niger from 1984 to 1996. In several field experiments in ICRISAT, the hourly values of net radiation were obtained through net radiometers mounted above the crop canopies. The growth and interception of PAR in a maize/pigeonpea intercrop and sole maize and sole pigeonpea crops grown in large plots were compared. The productivity of maize, sorghum, pigeonpea and a maize/pigeonpea intercrop in the operational research watersheds was measured in relation to the interception of PAR. In another study, it was shown that different shading ability of the crop canopies was one of the factors which determined the crop/weed competition balance and thus contributed to differential crop productivity observed in different cropping systems. Afterwards, when I worked at the World Meteorological Organization from 1996 to 2016 as the Chief of the Agricultural Meteorology Department, as the Director of the Climate Prediction and Adaptation Branch and as the Acting Secretary of the Intergovernmental Panel on Climate Change, a lot of work was done on Solar Radiation. Given all the above work on Solar Radiation, I emphasized the need for improved respect to Sun Bhagawan by Agrometeorologists at the end of this article.

Uncertainty modeling method of weather elements based on deep learning for robust solar energy generation of building

During the actual use stage, the uncertainty of weather leads to errors between the performance of building energy and the simulated values. Usually, uncertainty of weather cannot be eliminated, and difficult to quantify accurately due to complex occurrence rules. Based on the influence of weather uncertainty on solar power generation, this research propose a highly reliable and high-efficiency uncertainty modeling method based on two neural networks: (i) dual-stage attention-based recurrent neural network(DARNN): due to the use of two-stage attention mechanism, as the method to achieve importance interpretability in this study. (ii) Bayesian recurrent neural network(Bayesian RNN): regard the weight and bias value as an unknown distribution, as the method of uncertainty modeling in this study. DARNN analyzes the weight value of each weather element at each time point as the importance through a single learning, and the results show that the importance of solar radiation and relative humidity to solar power generation ranks in the top two. Based on the above results, Bayesian RNN establishes the probability distribution models of solar radiation and relative humidity at each time point of a year by learning the potential correlation between weather elements and taking the historical data of low importance weather elements as input.

Emergence timing and fixation height in Pachydiplax longipennis (Odonata: Libellulidae) at varying substrate density and sunlight exposure

Emergence substrate and sunlight penetration inherently trade off in patchy vegetation. Given the importance of solar radiation at emergence, we expected greater sunlight availability in sparse veg...

Evaluation of ten methods for estimating evaporation in a small high-elevation lake on the Tibetan Plateau

To quantify lake evaporation and its variations in time, ten methods for estimating evaporation at a temporal resolution of 10 days over a small high-elevation lake in the Nam Co lake basin of the Tibetan Plateau (TP) were evaluated by using eddy covariance (EC) observation-based reference datasets. After examination of the consistency of the parameters used in the different methods, the ranking of the methods under different conditions are shown to be inconsistent. The Bowen ratios derived from meteorological data and EC observations are consistent, and it supports a ranking of energy-budget-based methods (including the Bowen ratio energy budget, Penman, Priestley-Taylor, Brutsaert-Stricker and DeBruin-Keijman methods) as the best when heat storage in the water can be estimated accurately. The elevation-dependent psychometric constant can explain the differences between the Priestley-Taylor and DeBruin-Keijman methods. The Dalton-type methods (Dalton and Ryan-Harleman methods) and radiation-based method (Jensen-Haise) all improve significantly after parameter optimization, with better performance by the former than the latter. The deBruin method yields the largest error due to the poor relationship between evaporation and the drying power of the air. The good performance of the Makkink method, with no significant differences before and after optimization, indicates the importance of solar radiation and air temperature in estimation of lake evaporation. The Makkink method was used for long-term evaporation estimation due to lack of water temperature observations in lakes on the TP. Lastly, long-term evaporation during the open-water period (April 6 to November 15 from 1979 to 2015) were obtained; the mean bias was only 6%. A decreasing-increasing trend in lake evaporation with a turning point in 2004 was noted, and this trend corresponds to the published decreasing-increasing trend in reference evapotranspiration on the Tibetan Plateau and can be explained by variations in related meteorological variables.

Première évaluation de la distribution du pergélisol dans les Carpates roumaines (massif de Retezat) par la méthode BTS

A first estimate of permafrost distribution in the central part of the Retezat Mountains (Southern Carpathians, Romania) was computed using basal temperature measurements of winter snow cover as input data for an empirical-statistical modelling approach. During the 2012-2013 winter season, a total of 170 bottom temperature of snow cover measurements (Haeberli, 1973) were made. The permafrost distribution within the investigated area was modelled based on multiple linear regression analysis of the relationship between bottom temperature of snow cover measurements and five predictor variables: elevation, solar radiation, vegetation cover, slope and profile curvature. The final model, having an overall accuracy of 0.48, included only the first three variables as the main factors controlling permafrost occurrence within the investigated area, while slope and profile curvature proved to be statistically insignificant. Permafrost occurrence, as predicted by the model, covers 31 km2 (52% of the investigated area), of which 14 km2 is predicted as probable permafrost and the remaining 17 km2 is possible permafrost. The obtained results indicate the importance of solar radiation, elevation and vegetation cover in controlling alpine permafrost occurrence in the central part of the Retezat Mountains.

Ocular squamous cell carcinoma in Valle del Belice sheep: Histology and immunohistochemistry

Ocular squamous cell carcinoma (OSCC) in animals is a primary tumor of epithelial cells that may occur in different ocular and periocular tissues, especially the epithelial surfaces of the conjunctiva, corneoscleral junction, nictitating membrane, cornea and eyelid skin. This report describes histological and immunohistochemical features of four different clinical cases classified as OSCC in Valle del Belice sheep. Importance of solar radiation in the etiology of OSCC is discussed, together with other potential risk factors.

Stochastic dynamic simulation of the 100-kyr cycles in climate system

Based upon the stochastic resonance theory, the formation mechanism of 100-kyr cycles in climate system is numerically studied in the perspective of stochastic dynamics. In this study, firstly we combine the idealized albedo model with the geological evidence and observation in climate system to construct a new albedo model. Secondly, a bistable nonlinear system is constructed by introducing the albedo model into zero-dimensional energy balance model. Finally, based on this new system, with the solar radiation cycles and stochastic perturbation simultaneously taken into account, the variation of 100-kyr cycles is analyzed by numerical simulations. The results show that, when the noise intensity reaches a certain value, the stochastic resonance can be triggered. However, the noise intensity in this level does not exist in the actual climate system. In order to explain the formation mechanism of 100-kyr glacial-interglacial cycles forced by the weak solar radiation cycles, besides the solar radiation stochastic perturbation, the stochastic dynamic effects of the other “non-solar” radiation stochastic perturbation in the climate change processes should also be considered. The stochastic dynamic simulations taking the two types of stochastic perturbation into consideration show that, when the two types of appropriately observable stochastic perturbation are introduced, the stochastic resonance also can be generated. In this situation, the contribution rate of solar radiation stochastic perturbation is about 38%, which proves the importance of solar radiation stochastic perturbation in the formation of 100-kyr climate cycles. solar radiation, climate change, stochastic dynamics, stochastic resonance, energy balance model

Importance of solar radiation, temperature, relative humidity, and wind speed for calculation of reference evapotranspiration

This study aims to compare two form of Valiantzas’ evapotranspiration methods (one of the newest models) to detect the best method under different weather conditions. For this purpose, weather data were gathered from 181 synoptic stations in 31 provinces of Iran. The reference evapotranspiration was compared with the Food and Agriculture Organization Penman–Monteith method. The results showed that they are not suitable for provinces of Iran. Therefore, the methods were calibrated and preciseness of estimation was increased (the values of R2 were less than 0.99 for only five provinces in the modified methods). The new formulas estimated the reference evapotranspiration in the southeast of Iran and near the Persian Gulf (solar radiation >24.4 MJ m−2 day−1 and wind speed 2.50–3.50 m s−1) better than other provinces. The more precise methods were for SK (east of Iran) and for GO (north of Iran). Finally, a list of the best performances of each method was presented (using sensitive analysis) to use other regions and next studies according to temperature, relative humidity, solar radiation, and wind speed. The results are also useful for selecting the best model when we must apply the new formulas based on available data.

Watershed-scale controls on snow accumulation in a small montane watershed, southwestern Alberta, Canada

Snow accumulation in mountain headwater basins is a major water source, particularly in semi-arid environments such as southern Alberta where water resources are stressed and snowmelt supplies more than 80% of downstream runoff. Relationships between landscape predictor variables and snow water equivalent (SWE) were quantified by combining field and LiDar measurements with classification and regression tree analysis over two winter seasons (2010 and 2011) in a small, montane watershed. 2010 was a below average snow accumulation year, while 2011 was well above normal. In both the field and regression tree data, elevation was the dominant control on snow distribution in both years, although snow distribution was driven by melt processes in 2010 and accumulation processes in 2011. The importance of solar radiation and wind exposure was represented in the regression trees in both years. The regression trees also noted the lower importance of canopy closure, slope, and aspect, which was not observed in the field data. This technique could provide an additional method of forecasting annual water supply from melting snow. However, further research is required to address the lack of data collected above treeline, to provide a full-basin estimate of SWE. Copyright © 2012 John Wiley & Sons, Ltd.

Clima y radiación solar en las grandes ciudades: Zona Metropolitana de Guadalajara (Estado de Jalisco, México)

El objetivo de este trabajo es analizar la caracterización del clima y la radiación solar en la Zona Metropolitana de Guadalajara (ZMG) partiendo de los estudios realizados por investigadores e instituciones de gobierno en distintos años. Los resultados permiten conocer el clima regional y local, así como la trascendencia de la radiación solar en el impulso y desarrollo de nuevas tecnologías ambientales. Se concluye que la climatología de la zona es ideal para la captación y generación de energía.

Factors governing the removal of faecal indicator bacteria in the ecosystem of Lake Timsah, Egypt

Persistence of faecal coliforms, presumptive Vibrio cholerae and Vibrio parahaemolyticus at three stations in Lake Timsah were investigated in 2010. Samples were collected by day and at night. Bacterial counts were highest at the outlet of wastewater discharged into the lake (Station 1). As wastewater mixed with the lake water, bacterial counts decreased at Station 2 and were reduced by up to 90% at Station 3, approximately 1 km from Station 1. Counts of both faecal coliforms and V. cholerae were higher at night than by day. The reduction in the counts of faecal coliform bacteria in three microcosms showed that reduction of faecal coliforms was not only due to the effect of UV, but was a combined effect of both UV and predation. The microcosm experiment confirmed the importance of solar radiation over predation in reducing faecal coliform counts in aquatic environments.

Estimativa de propriedades termofísicas em campo usando modelos de transferência de calor e umidade

A condução de calor através dos componentes opacos da envoltória é um dos parâmetros que caracterizam o desempenho térmico das edificações e suas consequências em termos de consumo energético e conforto térmico. A envoltória pode ser descrita termicamente a partir de dois parâmetros: a condutividade térmica (λ); e a capacidade térmica volumétrica (ρ∙c). Estimar essas propriedades termofísicas em campo permite caracterizar elementos construtivos considerando aspectos como comportamento térmico em condições climáticas específicas, variação na qualidade de materiais, soluções locais de construção e desgaste de materiais. Este trabalho apresenta um método para estimar λ e ρ∙c em elementos homogêneos usando um teste não destrutivo que aproveita as oscilações naturais do clima. A temperatura e o calor superficial são medidos em uma amostra de concreto (com propriedades conhecidas) e os dados são tratados com uma técnica de processamento de sinal. A estimativa é executada com um modelo de transferência de calor e umidade integrado. As medições foram realizadas em seis dias durante um período de um mês, registrando dias com diferentes condições de céu, visando mostrar a importância da radiação solar como fonte de calor. Os resultados apresentaram uma diferença de 10-14% na estimativa das propriedades termofísicas.

Local Atmospheric Chemistry and Ozone Model (LACOM)

LACOM (Local Atmospheric Chemistry and Ozone Model) is a chemistry box model that can be applied to teaching and learning atmospheric chemistry at high schools, especially GLOBE (Global Learning and Observations to Benefit the Environment) schools, and at universities. The program code is written in Fortran and can be run on a PC under Microsoft Windows 95 or Windows NT, in MS-DOS prompt or using MS-Excel 97. Commercial graphic programs are used for data analysis. Using LACOM as a tool, students learn about the chemical complexity of the troposphere, the importance of solar radiation and photochemistry, the significant influence of emissions and depositions of gases, and the impact of meteorological parameters. Special attention is paid to tropospheric ozone. LACOM is appropriate for (i) simulating main features of a particular day, (ii) understanding the coupling between individual parameters, and (iii) predicting impacts of environmental problems such as increased pollution and ozone depletion in the lower atmosphere. As input the program needs meteorological data and information about local emissions. For the days simulated students can make environmental observations (e.g., daily minimum and maximum temperatures, and temperature, relative humidity, and cloudiness at noon) as GLOBE schools do continuously and use these data in the simulations.

Paleozoic Atmospheric CO 2 : Importance of Solar Radiation and Plant Evolution

Changes in solar radiation, as it affects the rate of weathering of silicates on the continents, and other changes involving weathering and the degassing of carbon dioxide (CO(2)) have been included in a long-term carbon-cycle model. These additions to the model show that the major controls on CO(2) concentrations during the Paleozoic era were solar and biological, and not tectonic, in origin. The model predictions agree with independent estimates of a large mid-Paleozoic (400 to 320 million years ago) drop in CO(2) concentrations, which led to large-scale glaciation. This agreement indicates that variations in the atmospheric greenhouse effect were important in global climate change during the distant geologic past.

Stochastic modelling of temperatures affecting the in situ performance of a solar-assisted heat pump: The univariate approach

Univariate stochastic modelling, using Box-Jenkins methods, is carried out for three air temperatures which can influence the performance of a solar-assisted heat pump system. In this system, external ambient air (the low grade source) is pre-heated by the conventional tiled roof of an occupied domestic residence. The air then crosses the evaporator of an electrically driven split heat pump which is situated in the roof space. Autocorrelation coefficients are presented for time series of the following dry-bulb temperatures: the external air, the residence internal (lounge) air, and the air in the roofspace after pre-heating but prior to crossing the heat pump evaporator. Hourly data relating to a two-week period in the heating season was utilised, providing a 336-h dataset. Univariate models fitted to the first 300 observations were validated by forecasting ahead for the remaining 36 h in steps of 1 h. Comparison of forecasted and measured values showed good agreement, except for a 4-h period in which the intensity of solar radiation exceeded that which prevailed during the modelled period. It is concluded that the Box-Jenkins approach can be used to develop univariate mathematical models which adequately describe building and climate thermal behaviour, and that the importance of solar radiation in this respect should not be overlooked.

Possible Role of Solar Radiation on the Viability of Some Air Fungi in Egypt

The high occurrence of Alternaria humicola and the moderate occurrence of Stemphylium verruculosum, Rhizopus nigricans, and Epicoccum nigrum in the air of Egypt could be correlated to their apparent resistance to solar radiation. Cladosporium herbarum, Aspergillus niger, and Penicillium oxalicum, although highly occurring, were light-sensitive. The miniumum solar radiation in November, coupled with the highest total fungal catch, dominated by Cladosporium herbarum, reveals the importance of solar radiation as a factor with direct effect on the air fungal population.

Relative importance of solar radiation and gravitational tide in causing geomagnetic variations

For an assumed model of the ionosphere, partial coherence functions have been computed to investigate the contribution of solar radiation and of gravitational tide in causing geomagnetic variations (and hence the tides in the ionosphere). It is found that (1) at the diurnal frequency solar radiation contributes about 99% to geomagnetic variation, the gravitational contribution being negligible, and (2) at the semidiurnal frequency solar radiation and gravitational tide contribute nearly 90% and 10%, respectively, to geomagnetic variations.

Competition for Light between Annual Species of Trifolium during the Vegetative Phase

The goal of the investigation was the evaluation of the relationship of leaf area and position to dry matter production by the species components of mixed (two species) communities in contrast to their production in simple (single species) communities. The species selected for study were the closely related winter-annual legumes, Trifoliur subterraneum L. (subterranean clover), T. hirtum All. (rose clover), and T. incarnatum L. (crimson clover). These three clovers are quite compatible under field conditions when sown together for pasture (Williams, Love, and Berry 1957). Their relative amounts fluctuated widely, however, during successive years under conditions of natural regeneration. Since the factors underlying these fluctuations must be of considerable ecological import, a series of investigations was initiated to study the influence of mineral nutrition, temperature, moisture, light, and other factors on the competitive ability of these three species. Species interactions were determined in relation to natural light, while all other factors were kept as favorable and as constant as possible among the communities and the species within communities. Black (1957) and Donald (1961), in recent reviews of work on competition for light in crops and pasture communities, emphasized the importance of solar radiation in determining productivity. Light is of major importance to the vegetative productivity of herbaceous legumes, which are considered to be heliotropes, i.e. plants requiring high light intensity for rapid growth (Black 1957). A large and significant part of the winter annual's life cycle, however, extends through periods of short days and a high proportion of cloud cover. The competition experiment was therefore conducted under these circumstances in the Mediterranean-type climate of Adelaide, South Australia. The experimental site was selected because of its similarity to the low elevation, intermediate rainfall range areas of Californiia.

The Importance of Solar Radiation in the Development of Growing Pigs

The results obtained would seem to show 1. That direct light is necessary for the normal development of pigs. 2. That young pigs fed what would ordinarily be called well balanced rations but deprived of light will develop rickets. 3. That similar young pigs fed in the same manner but having access to open yards or direct light will remain normal. 4. That the light secured through ordinary window glass is of little value in preventing rickets in young pigs. 5. That Vita glass is of very doubtful value. Certainly if superior at all, it is not sufficiently superior to ordinary glass to justify the great difference in price. 6. That, by furnishing an abundance of fresh green legumes or probably other green plant growth, the occurrence of rickets will be prevented. 7. That young pigs show the effect of restricted light much more quickly than older ones. 8. That pigs 3 or 4 months of age that have up to that period developed normally seem to be able to withstand comparatively long periods of restricted light. 9. That access to direct light will cause rapid improvement in affected animals and eventually restore pigs showing evidence of most advanced cases of rickets sufficiently to be marketable. 10. That entirely apart from the development of rickets, the pigs which received direct light made significantly greater gains than all other groups in the experiment. 11. That, in view of the results obtained in this experiment, it would appear that the most satisfactory system of housing for young growing pigs the year round is to provide them with comfortable sleeping quarters with open yards attached to which they can have access at all times. (Scientific Agriculture, Vol. XI, No. 1, 1930.