Impacts of climate change on irrigation water requirements for rice–wheat cultivation in Bagmati River Basin, Nepal

摘要: This study highlights the spatial and temporal impacts of climate change on rice–wheat cropping systems, focusing irrigation water requirement (IWR) in Bagmati River Basin Nepal. The outputs from a general circulation model (HadCM3) for two selected scenarios (A2 B2) IPCC three time periods (2020s, 2050s, 2080s) have been downscaled compared to baseline climatology. CROPWAT 8.0 is used estimate requirements. IWRs show different trends physiographic regions growth stages rice wheat. A decreasing trend Mid Hills High indicates that farmer-based small schemes are sufficient meet However, Terai region, where there an increasing IWRs, deficit volume needs be supplied potential large-scale schemes.