Estimation of wheat water requirement under climate change in Moghan plain (Parsabad)

Determining the water requirement of crops in the upcoming period and having an overview of it is essential in water resources management planning and using it we will be able to determine critical areas. The purpose of this research is to estimate the water requirement of wheat using general circulation model data (HadGEM2-ES) by the latest Climate Change Report (Fifth Report) as Representative Concentration Pathway scenarios (RCP), which is scaled using LARSWG model under RCP85 scenario. To this end, 30-year data (1990–2019) were entered into the model, and climatic data were predicted daily for the next 40 years in two time periods (2021–2040) and (2041–2060).The results show that over the 40-year period, all three parameters of maximum, minimum temperature and precipitation will have an increasing trend.In the next step, the data generated to calculate the water requirement of wheat in Pars Abad plain were entered into CROPWAT 8.0 software and it was observed that increasing temperature leads to increase evapotranspiration and increasing water requirement of wheat by 3 to 5% under climate changing.