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The aim of this study was to provide a reliable estimate of the amount of solar radiation in Kermanshah province by using “Liu and Jordan” model in order to develop solar sites. The amount of atmospheric elimination in each month was calculated using an index called clearness index () and the results were applied on different slopes, aspects and heights. Then, according to the obtained results, amounts of direct, diffuse and total radiation were calculated in different slopes of the region and the relevant maps were consequently drawn. The results showed that the minimum amount of atmospheric elimination and thus the maximum amount of received radiation in the province occurs in late spring and summer due to the increase of clearness index () with a maximum of 1360 cal/cm²/day in May. the least amount of received radiation occurs in Janury equal to 386.3 cal/cm²/day. Radiation variations at the provincial level are high between lowlands and highlands in Janury and December, according to the angle of radiation and significant elevation changes in the region. However, in summer, distribution of surface radiation is almost identical because of high solar radiation, and thus standard deviation amount of received radiation is reduced. The highest amount of radiation is received in Javanrood city as much as 528.1 cal/ cm²/day due to greater heights, and the lowest amount is received in Qasr-e Shirin city as much as 443.6 cal/ cm²/day due to lower heights.

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Abstract
The extention of Snow cover and its spatial and temporal changes considered as a basic parameter in climatic and hydrologic studies. Data from satellite images due to the low cost and the large extention of cover are, effectively help the identifying of the snowy basins. Since the satellites are able to imaging a surface at different times, this will allow snow survey studies to investigate the spatial and temporal distribution of snow. In this research, Snow line changes and the surface temperature line in Alborz Mountains using NOAA-AVHRR satellite images since 2006 from 2015 was studied. The results showed that at the study period, maximum area of snow have been observed in April 2015, with the amount of 12051 square kilometers and the minimum area snow have been observed in June 2008, with the amount of 33 square kilometers. The average of the lowest elevation of snow covered areas, have been observed in April 2007, with the amount of 2662 meters and its highest value have been observed in June 2008 with the amount of 3820 meters. Also the most of the snow line change occurred between the years 2007 to 2008. Moreover, in almost of 15 years, the isoterm of zero degrees Celsius, matches with the snow line and its elevation has changed as the snow area is changed.
 

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The smallest change in energy exchange of Earth System Shifts the balance of life. In order to be aware of the solar radiation Balance, Recognition of the measure of Balance level of the input and output components of radiation of input Short wavelength to the surface of the earth and Long Output Wavelength, it is necessary from the earth. To study the energy balance of input and output in Iranian plateau, the input and output radiation data of NCEP / NCAR site was used With a resolution of 2.5 * 2.5 *, including 46 cells in Iran,. For each season, a representative month was considered And correlation, confidence level, coefficient of determination and amount of oscillation of input and output radiation were calculated in different regions of Iran. Finally, some calculations were presented spatially with the IDW method. The results showed that the maximum short-wave wavelength was 230 watts per square meter in August and the lowest was 52 watts per square meter in November. The highest long-wavelength output in August was 65 watts per square meter, and the lowest amount was January and November with 20 watts per square meter. The highest the amount of output increase has been occurred in August in the east of province South Khorasan with a correlation of 0.59 to 112 watts per square meter in 2001. In decreasing output changes, except for May, there was a decrease in the rest of the months. The highest long-wavelength output was in the northwest and in the provinces of Ardabil and Guilan.