Global solar radiation characteristics at Dumdum (West Bengal)

Abstract

The data of the hourly global solar radiation (G) on a horizontal surface of Dumdum/ Gangetic West Bengal for the period 1980 to 2010 has been obtained. The diurnal extra terrestrial solar radiation for the station (22.39° N, 88.27° E) has been computed and then the clearness index has been calculated. The diurnal variations of the results have been studied. Also the daily total values and its monthly and seasonal averages as well as their frequency distribution in percentage have been computed and examined. The seasonal and climatic effects of the fluctuation of the results have been discussed. These effects have been particularly large during pre monsoon season (i.e. March to May); the period which experiences the thunderstorm activity the most in this area and this fact may be attributed as one of the cause for generation of the thunderstorm. The clearness index (G/G_o) shows that the incoming solar radiation is almost halved on reaching the earth. Also the comparative statistical as well as graphical study of average total global solar radiation with the average maximum temperature confirms once again the fact that the total global solar radiation is fairly related to average maximum temperature in correlation (0.77) as well as in wave form.