Monitoring physiographic rainfall variation for sustainable management of water bodies in India

Abstract

About 90% of the natural disasters are of meteorological or hydrometeorological origin. Disasters such as earthquakes and tsunamis are occasional, but rainfall related hazards are frequent and needs constant monitoring. The annual average rainfall over India is 1166 mm out of which 78% is received in the hydrological wet season (mostly summer monsoon rainfall) of 135 days from 30 May to 11 October (Ranade et al., 2007) and is widespread over the country with large spatial variability due to large variation in intensity and frequency of rain-inducing disturbances such as monsoon depressions/lows, monsoon trough position, and physiography. There is a large intra-seasonal variability in this hydrological wet season. Rainfall during the remaining period though restricted to limited areas (i.e. during winter over northernmost and east peninsular India, during summer over northeast and southwestern India and during post-monsoon season over south peninsula, east coast and northeastern part of India) is crucial. © 2010 Springer Science+Business Media B.V.