Comparison between Ground-based Synoptic Data and ERA5 Reanalysis Data in Iran

This work investigates the performance of ERA5 reanalysis data released by ECMWF to estimate the air surface temperature over Fars province in southern Iran. The monthly average temperature extracted from ERA5 gridded data for 5 place in region is compared with the observational data obtained from synoptic station. The correlation coefficient and mean bias error are used to evaluate data. The monthly temperature estimated by ERA5 shows positive biases (ranges from 1.0 to 4.66°C) and against the ground-based synoptic data except in Kazerun station with -6.08 MBE. The value of biases can be used to correct-bias the estimations. Generally, the results show ERA5 underestimates the monthly average temperature in most stations.