Indus River Basin: Future climate and water budget

Abstract

Indus River Basin (IRB) in the western Himalayas is very important for the sustainability of livelihood, food and water security of its inhabitants. In the present work, changing climate and its impact on water budget of IRB is discussed. For this, simulation from a regional climate model (REMO) is studied for present (1970–2005) and future (till 2099) climate under various representative concentration pathways (RCPs). It is distinctly seen that, there is a likely increased (decreased) precipitation over upper (lower) IRB under both the RCPs. Moreover, a heterogeneous warming pattern is projected over the region with season-specific response of warming towards increasing greenhouse gases (GHGs). Higher (lower) evapotranspiration over the lower (central) IRB raise serious concerns about water issues. The changes in climatic parameters will have huge impact on the associated water budget. Linkages of water budget with the corresponding precipitation, temperature, evapotranspiration and runoff provide possible mechanisms for depleting (enhancing) water storage over the lower (upper) IRB during DJF (JJAS). This will have impact on agriculture, crop and water security of the region and thus underlines the need for adaptation policies at governance level.