Impacts of climate change on the flow of the transboundary Koshi River, with implications for local irrigation

This study assesses climate change impacts on the hydrological regime of a river basin and its implications for future irrigation water availability in the Koshi River basin using RCPs 4.5 and 8.5 over short-term (2016-2045), mid-century (2036-2065) and end-of-century (2071-2100) periods. Average flow in the Koshi River is projected to increase. Projections of average minimum monthly river flow suggest that the areas of winter wheat and monsoon paddy rice could be increased. However, the planting period of paddy rice should be delayed by one month (July to August) to capture the expected increased water availability in the river.

Automated summary

The study indicates that water availability in the Koshi River basin will increase, favoring the cultivation of winter wheat and monsoon paddy rice. However, to better utilize the increased water resources, the planting period for paddy rice should be delayed by one month in the future.