IMPACT ASSESSMENT OF RAINFALL ON STREAMFLOW SENSITIVITY: A CASE STUDY OF KUNHAR RIVER BASIN, PAKISTAN

Abstract

Accurate and reliable estimates of streamflow sensitivity to climate drivers are needed to integrate the effects
of worldwide climate change as a result of global warming in future water supply planning. In this case, we used the
elasticity model to assess the sensitivity of the streamflow to rainfall for Kunhar River basin considering three stream
flow gauging stations including Kunhar River at Naran, Kunhar River at Talhata bridge, and Kunhar River at Garhi
Habib Ullah for the study period of 1963-2007. The precipitation elasticity of streamflow ‘εp’, is represented by a ratio
of the proportional change occurring in streamflow divided by the proportional change occurring in mean annual
precipitation.
The results of the study present the sensitivity of the Kunhar River basin at the three gauging points i.e. at Naran,
Talhata bridge, and Garhi Habibullah stations as 0.3, 0.5 and 0.8 respectively. This means that a. deviation of 1% from
the long duration mean rainfall will bring 0.3%, 0.5% and 0.8% change in annual discharge at the afore mentioned
gaging sites of the Kunhar river respectively. This study findings can be used to guide the use of elasticity techniques to
quantify hydrological reactions to climate change that inform the region's policies for long-term water management.