Estimating climate change impact on actual evapotranspiration using CMIP6 data and SEBAL

Abstract:

Global circulation models (GCMs), established by several modeling groups under the coupled model inter-comparison project (CMIP) and these models are used extensively for studying the climate change impacts of past, present and future at global scale. Hydrological variables such as actual evapotranspiration (AET) are an essential factor that determine the exchange of water and heat energy between the land surface and atmosphere. It also has an impact on the available
water resources and crop water assessment in agricultural areas. The main objective of the study is to assess the change in the future AET over a part of the river basin in India on a seasonal and annual basis due to changes in the past, present, and future climate using coupled model inter-comparison project phase 6 (CMIP6) data. The study will be carried out for the period of 1986-2005 as the past, and for the future periods - 2020-2039, 2040-2059, 2060-2079, and 2080-2099. The assessment will reveal whether there will be an increase or decrease in the AET due to changes in the climate, which will significantly impact the water resources of the study area. For this purpose, Surface Energy Balance Algorithm for Land (SEBAL) model will be used to estimate AET for the annual, pre-monsoon, monsoon, post-monsoon, and winter seasons of India.

Keywords: CMIP6, climate change, GCMs, actual evapotranspiration, SEBAL, India.