India receives 80% of its annual rainfall during the south west monsoon season of June to September. Rainfall over the country during this season shows a wide range of spatial variation due to orographic influences and preferential occurrence of rain-bearing systems in certain regions. *How is rainfall measured? 1 inch of rain in 15 minute period is a lot more water than 1 inch of rain in the last one month. So we really don’t know how much it’s rained if we don’t know the time period we’re talking about. What does 1 inch, 2 inch or number of inches of rain in some time period mean? Well if all the rain that falls stays right where it lands – meaning it doesn’t run off and accumulate in streams and rivers and eventually in lakes and oceans and it isn’t absorbed into the ground then 1 inch of rain in an area is enough to evenly cover the ground in that area with a layer of water 1 inch deep.
**We cannot define aridity according to only one parameter such as the annual rainfall; this would mean land receiving an annual rainfall of less than 100 mm would be desert, those receiving 100 mm to 400 mm would be arid: in this case the Thar “desert” in its totality would belong to the second category, since even its least rain fed destrict, Jaisalmer, receives 160 mm of rain. One must, however, also keep in mind two factors : firstly, the distribution of rain throughout the year – ninety per cent of the rainfall occurs during the monsoons, from July to mid-September and secondly the torrential nature of the rainfall which does not allow an optimal usage. In fact this can lead to floods, as was the case in July 1979, in the Luni basin. Moreover winds, which are a powerful agent of erosion and evaporation, contribute to the further desertification of an already arid region. If we also add the temperature factor (in May the minimum temperature is around 27°C and the maximum around 43°C in Jaisalmer and barely lower in Jodhpur and Bikaner), we can accept the term desert for Rajasthan as Indian Geography and Anupam Mishra do.
Cherapunji is one of the highest rainfall region in the world, with a minimum annual rainfall of 5 mts; yet it is listed as a district where there are severe water problem; on the other hand, with just 160 mm of water, Jaisalmer has always had drinking water. In one case, the environment is conducive to a symbiosis and patient dialogue with the realities of nature, in the other it is not.
In Rajasthan, more particularly in the desert, water work was never considered as work but came to be viewed as a moral duty; that is why it was able to rise far above what is today called community project, to take the beautiful shape of a samagra jal darshan, a perfect water philosophy. Society has undertaken the work on water with great pride : not as a challenge but indeed in a spirit of humility and duty. This has taken the visible shape of kuins, tankas, kundis, talabs and others. But there is also an invisible form to it, a form which is not shaped by bricks and mortar but by love and the legendary generosity of the water culture of this region.
** The Radiant Raindrops of Rajasthan by Anupam Mishra