Theme 7-6-Hydrologic sensitivity of some Indian basins to expected climate change and its effect on water availability using disaggregated GCMs outputs.

Abstract

Scientific studies based on General Circulation Models (GCMs) indicate a significant change in global climate during the current century. Such changes become all the more important as they may also affect the water availability of a region. However because of computational limitations, regional distributions of these changes are still not available. This paper utilises a disaggregation technique to downscale the GCMs predictions (precipitation) to catchment scale. The hydrologic sensitivity analyses of four Indian basins, namely, the Damanganga, Sher, Kolar and Hemavati, located in different agro-climatic regions are carried out using these disaggregated GCMs outputs and a catchment scale conceptual rainfall-runoff model. The study reveals that if substantial hydrologic changes materialize due to climate change predictions based on GCMs, it may have serious implications on many aspects of water resources, particularly agriculture, and thus may affect adversely the Indian economic performance and social progress as agriculture being the principal source of income for Indian economy.