Comparison of horizontal wind observed by wind profiler radars with ERA5 reanalysis data in Anhui, China

Abstract

The wind profiler radar (WPR) network in Anhui Province in China completed the construction in 2019 to improve the warning capacity for meteorological disasters. To verify its proper performance, vertical profiles of horizontal winds were compared with ERA5 reanalysis data from January to December 2021. The results show that the WPRs demonstrate good capability in measuring atmospheric wind due to their high data collection rate (> 80%). Overall, the data availability of the WPRs decreases with increasing altitude, exceeding 90% below 3 km during the daytime without precipitation. In terms of seasonal variability, the annual mean effective detection height reaches a maximum value at 4–6 km in summer and a minimum value at approximately 2 km in winter. Comparison analyses show that the wind measurements by the WPRs show excellent agreement with the ERA5 zonal (correlation coefficient > 0.89 and standard deviation < 2.57 m/s) and meridional winds (correlation coefficient > 0.76 and standard deviation < 3.26 m/s) over most WPR stations in Anhui, China. Additionally, the biases of winds between WPR and ERA5 generally follow a Gaussian distribution pattern, most of which are all close to zero. In particular, the differences in horizontal wind between WPR and ERA5 increase with altitude, with a much lower bias present in the lower layer. In addition, due to the difference in atmospheric turbulence between day and night, statistical parameters of comparison during daytime behave better than those at night. These findings indicate that the WPR network in Anhui is capable of providing good quality wind data, laying a solid data foundation for the improvement and development of the boundary layer scheme in the future.