Jaisalmer kshetra me samvahani meghon ki radar pratidwaniyon ka addhyayan

Abstract

Convection of water vapour due to natural heat results in formation of cumulus cloud and then cumulonimbus. Thunderstorm being one of the main agencies of energy exchange in atmosphere and also being the potential source of precipitation on the surface of the earth. An understanding of their frequencies of occurance over a region is useful in many studies like global electric circuit, global energetic etc. Thunderstrom activities, precipitation and many other issues related with thunderstorm over a region are strongly linked with each other. A climatological study of thundrstrom activity over and around Jaisalmer has not so far been done. In the present work, attention has been focused on conducting a comprehensive study of frequency of occurrence of thunderstorm over and around Jaisalmer.

Most of high impact weather phenomenon on mesoscale like hailstorm, heavy rain and squalls are caused by thunderstorms. These cause loss of life, damage to crops and property. Authors have analysed the radar echoes for the period of 19 April 1993 to 31 December 2010. Radar echoes have been arranged according to height and then monthwise also. Complete year has been catogerised into three main seasons, i.e., pre monsoon (March to May) monsoon (June to September) and post monsoon (October to February). Radar echoes have been analysed according to their heights and frequencies. For pre monsoon season in the month of March echoes frequencies found less but for April and May their frequencies as well as height of echoes found in increasing order. For monsoon period, June to July the frequencies as well as height of echoes observed in increasing order and these months are mainly rainy months at Jaisalmer but in the month of August and September the frequencies and height of echoes observed in decreasing order. For post monsoon period, in the months of October, November and December the frequencies and height of echoes observed very less, but in the month of January and Febuary due to western disturbances the frequencies of echoes increases but height of echoes are not enough.