Atmospheric warming induced changes in future rainfall and implications on water and agriculture in India

Influence of atmospheric warming on future rainfall of India has been discussed in this mini review paper. The projected rainfall change under various atmospheric warming scenarios is likely to have both positive and negative implications on agriculture and water supply because on account of varations in rainfall pattern across the country. Rise in rainfall is seen over all states except Punjab, Rajasthan and Tamil Nadu, which show slight decrease in precipitation in the future scenarios. Marked increase in rainfall is reported over an extensive area covering the Western Ghats and northwestern peninsular India including Maharastra and the adjoining parts of Andrapradesh, Madhyapradesh and Karnataka. The annual maximum peak in outflow in the sub basin of Mahanadi has exceeded from the present level of about 20000 cumecs under control scenario to a maximum level of 37000 cumecs under Green House Gas (GHG) scenario, such an increase in flood peak may be detrimental to a large number of existing structures on these drainage system. The number of drought weeks has considerably increased during GHG scenario barring about five sub basins out of the 21-sub basins of Krishna.