<span style="white-space:normal;">Observing and studying the solar radiation during solar eclipses is important in knowing the changes that occur to the environmental elements during this event. The ma...<span style="white-space:normal;">Observing and studying the solar radiation during solar eclipses is important in knowing the changes that occur to the environmental elements during this event. The main objective of this paper is the performance of the incoming variation of solar radiation components, global, direct and diffuse and their fractions during the partial annular solar eclipse on June 21</span><sup style="white-space:normal;">st</sup><span style="white-space:normal;">, 2020 in Helwan, Egypt (Lat. 29.866</span>°<span style="white-space:normal;">N and Long. 31.20</span>°<span style="white-space:normal;">E) has been made. A pyrheliometer for measuring the direct solar radiation, in three different bands;direct yellow (</span><em style="white-space:normal;">Y</em><span style="white-space:normal;">), direct red (</span><em style="white-space:normal;">R</em><span style="white-space:normal;">), direct infrared (</span><em style="white-space:normal;">IR</em><span style="white-space:normal;">), and also the total direct band (</span><em style="white-space:normal;">I</em><span style="white-space:normal;">);A pyranometers for measuring the different components of global solar radiation (</span><em style="white-space:normal;">G</em><span style="white-space:normal;">), global ultraviolet (</span><em style="white-space:normal;">G<sub>UV</sub></em><span style="white-space:normal;">), global infrared (</span><em style="white-space:normal;">G<sub>IR</sub></em><span style="white-space:normal;">) and a meteorological station to measure the different meteorological parameters. The duration of the solar eclipse was 01 h:59 m, and the maximum magnitude of the eclipse in this region was 0.449. The depression is clear at the solar radiation of all components due to the annular solar eclipse, while the depressions of the diffuse and global infrared solar radiation are lower. In all direct radiation compounds (</span><em style="white-space:normal;">I</em><span style="white-space:normal;">, </span><em style="white-space:normal;">Y</em><span style="white-space:normal;">, </span><em style="white-space:normal;">R</em><span style="white-space:normal;"> and </span><em style="white-space:normal;">IR</em><span style="white-space:normal;">) are greatly affected by the eclipse. The diffuse fraction </span><em style="white-space:normal;">K<sub>d</sub></em><span style="white-space:normal;"> is higher in the early time, before the partial eclipse, but during the partial annular eclipse time </span><em style="white-space:normal;">K<sub>d</sub></em><span style="white-space:normal;"> values are suffers variation and through the day, where the values of </span><em style="white-space:normal;">K<sub>d</sub></em><span style="white-space:normal;"> lies between </span><em style="white-space:normal;">K<sub>t</sub></em><span style="white-space:normal;"> and</span><em style="white-space:normal;"> K<sub>UV</sub></em><span style="white-space:normal;">. The values of direct infrared solar radiation are dominant before and after the partial annular solar eclipse. The intensity of color bands (W<span style="white-space:nowrap;">∙</span>m</span><sup style="white-space:normal;"><span style="white-space:nowrap;">−</span>2</sup><span style="white-space:normal;"><span style="white-space:nowrap;">∙</span>nm</span><sup style="white-space:normal;"><span style="white-space:nowrap;">−</span>1</sup><span style="white-space:normal;">) are </span><em style="white-space:normal;">DIB</em><span style="white-space:normal;">3 ></span><em style="white-space:normal;"> DIB</em><span style="white-space:normal;">2 > </span><em style="white-space:normal;">DIB</em><span style="white-space:normal;">4, and </span><em style="white-space:normal;">DIB</em><span style="white-space:normal;">1 is opposite direction with </span><em style="white-space:normal;">DIB</em><span style="white-space:normal;">3 and </span><em style="white-space:normal;">DIB</em><span style="white-space:normal;">2, the highest intensity is direct red and the lowest intensity is the direct infrared. The highest values of extinction coefficient in (</span><em style="white-space:normal;">G<sub>IR</sub></em><span style="white-space:normal;">) solar radiation and the lowest values occur in (</span><em style="white-space:normal;">G<sub>UV</sub></em><span style="white-space:normal;">) solar radiation, while the values of (</span><em style="white-space:normal;">G</em><span style="white-space:normal;">) solar radiation occur between them. In general trend, the values of extinction coefficient during the partial eclipse are increasing, while the minimum values of extinction coefficient occur at noon time due to the air mass is less value in the noon.</span>展开更多
文摘<span style="white-space:normal;">Observing and studying the solar radiation during solar eclipses is important in knowing the changes that occur to the environmental elements during this event. The main objective of this paper is the performance of the incoming variation of solar radiation components, global, direct and diffuse and their fractions during the partial annular solar eclipse on June 21</span><sup style="white-space:normal;">st</sup><span style="white-space:normal;">, 2020 in Helwan, Egypt (Lat. 29.866</span>°<span style="white-space:normal;">N and Long. 31.20</span>°<span style="white-space:normal;">E) has been made. A pyrheliometer for measuring the direct solar radiation, in three different bands;direct yellow (</span><em style="white-space:normal;">Y</em><span style="white-space:normal;">), direct red (</span><em style="white-space:normal;">R</em><span style="white-space:normal;">), direct infrared (</span><em style="white-space:normal;">IR</em><span style="white-space:normal;">), and also the total direct band (</span><em style="white-space:normal;">I</em><span style="white-space:normal;">);A pyranometers for measuring the different components of global solar radiation (</span><em style="white-space:normal;">G</em><span style="white-space:normal;">), global ultraviolet (</span><em style="white-space:normal;">G<sub>UV</sub></em><span style="white-space:normal;">), global infrared (</span><em style="white-space:normal;">G<sub>IR</sub></em><span style="white-space:normal;">) and a meteorological station to measure the different meteorological parameters. The duration of the solar eclipse was 01 h:59 m, and the maximum magnitude of the eclipse in this region was 0.449. The depression is clear at the solar radiation of all components due to the annular solar eclipse, while the depressions of the diffuse and global infrared solar radiation are lower. In all direct radiation compounds (</span><em style="white-space:normal;">I</em><span style="white-space:normal;">, </span><em style="white-space:normal;">Y</em><span style="white-space:normal;">, </span><em style="white-space:normal;">R</em><span style="white-space:normal;"> and </span><em style="white-space:normal;">IR</em><span style="white-space:normal;">) are greatly affected by the eclipse. The diffuse fraction </span><em style="white-space:normal;">K<sub>d</sub></em><span style="white-space:normal;"> is higher in the early time, before the partial eclipse, but during the partial annular eclipse time </span><em style="white-space:normal;">K<sub>d</sub></em><span style="white-space:normal;"> values are suffers variation and through the day, where the values of </span><em style="white-space:normal;">K<sub>d</sub></em><span style="white-space:normal;"> lies between </span><em style="white-space:normal;">K<sub>t</sub></em><span style="white-space:normal;"> and</span><em style="white-space:normal;"> K<sub>UV</sub></em><span style="white-space:normal;">. The values of direct infrared solar radiation are dominant before and after the partial annular solar eclipse. The intensity of color bands (W<span style="white-space:nowrap;">∙</span>m</span><sup style="white-space:normal;"><span style="white-space:nowrap;">−</span>2</sup><span style="white-space:normal;"><span style="white-space:nowrap;">∙</span>nm</span><sup style="white-space:normal;"><span style="white-space:nowrap;">−</span>1</sup><span style="white-space:normal;">) are </span><em style="white-space:normal;">DIB</em><span style="white-space:normal;">3 ></span><em style="white-space:normal;"> DIB</em><span style="white-space:normal;">2 > </span><em style="white-space:normal;">DIB</em><span style="white-space:normal;">4, and </span><em style="white-space:normal;">DIB</em><span style="white-space:normal;">1 is opposite direction with </span><em style="white-space:normal;">DIB</em><span style="white-space:normal;">3 and </span><em style="white-space:normal;">DIB</em><span style="white-space:normal;">2, the highest intensity is direct red and the lowest intensity is the direct infrared. The highest values of extinction coefficient in (</span><em style="white-space:normal;">G<sub>IR</sub></em><span style="white-space:normal;">) solar radiation and the lowest values occur in (</span><em style="white-space:normal;">G<sub>UV</sub></em><span style="white-space:normal;">) solar radiation, while the values of (</span><em style="white-space:normal;">G</em><span style="white-space:normal;">) solar radiation occur between them. In general trend, the values of extinction coefficient during the partial eclipse are increasing, while the minimum values of extinction coefficient occur at noon time due to the air mass is less value in the noon.</span>
