Influence of agricultural activity on the surface climate of New Delta of Egypt using the RegCM4

The present study aims to examine the influence of a cropped area (of New Delta in Egypt) on the temperature extremes (T_max and T_min), total surface precipitation (Pr), and potential evapotranspiration (PET; as an important variable in the water cycle) using a regional climate model (RegCM4). The RegCM4 was downscaled by the MPI-ESM-MR (as the lateral boundary condition; LBC) over the Middle East and North Africa (MENA) with 50 km grid spacing and then nested over Egypt with 20 km grid spacing. After that, the RegCM4 was evaluated with respect to an observational dataset. To consider the effect of the cropped area, two experiments were conducted: one doesn’t include the cropped area (CTRL) and the other one considers the cropped area (EXP). The two experiments were integrated from 1980 to 2100 considering the future scenario representative concentration pathway 4.5 (RCP45). The results showed that the cropped area induces a reduction in both T_max and T_min (by 0.5 – 1.5ºC) as well as a reduction in PET (by 0.2 mm day^-1). Furthermore, there was no notable change in the simulated Pr. In conclusion, the RegCM4 is considered a useful tool to examine the possible effects associated with the cropped area. Also, considering more LBC is necessary to account for the uncertainty associated with the atmospheric forcing.