风廓线雷达在成都地区的适用性分析

Applicability Analysis of Wind Profiler Radar in Chengdu

利用2020年1月至2020年7月成都市温江区气象站L波段探空雷达资料,基于风场和大气折射率结构常数(C^(2)_(n))的比对分析,探究了风廓线雷达产品在成都地区的适用性。结果表明:风廓线雷达反演的水平风场与对应时刻L波段探空雷达测风资料在各高度层均呈显著正相关(p<0.05)。在低层(<2.5 km),风廓线雷达反演的水平风速较L波段探空雷达偏小,约0~1 m·s^(-1),各高度层水平风速有效样本率在90%~100%波动;在高层(>2.5 km),风廓线雷达反演的水平风速较L波段探空雷达偏小,约0.5~2 m·s^(-1),各高度层水平风速有效样本率在70%~90%波动。另外,风廓线雷达水平风向的有效样本率随高度上升呈波动增长趋势。在大气处于中等不稳定、弱不稳定、中性或弱稳定条件下,风廓线雷达C^(2)_(n)廓线与对应时刻L波段探空雷达反演得到的C^(2)_(n)廓线具有较好的一致性;在大气处于极不稳定或中等稳定条件下,风廓线雷达C^(2)_(n)廓线与对应时刻L波段探空雷达反演得到的C^(2)_(n)廓线虽呈现显著的正相关(p<0.05),但二者在数值上却存在较大的差异。降水是影响风廓线雷达反演精度的另一重要因子,降水条件下所测量水平风速的误差显著增大。

The applicability of wind profiler radar products in Chengdu is investigated using L-band sounding radar data from the Wenjiang District Weather Station,Chengdu,from January 2020 to July 2020,based on the wind field and atmospheric refractive index structure constant(C^(2)_(n)).At all levels,there is a significant positive correlation(p<0.05)between the horizontal wind field retrieved by the wind profiler radar and L-band sounding radar wind data measured at the same time.The horizontal wind speed retrieved by the wind profiler radar is about 0-1 m·s^(-1) smaller than the L-band sounding radar at the low level(<2.5 km),and the effective sample rate of the horizontal wind speed at each level fluctuates between 90%and 100%.The horizontal wind speed retrieved by the wind profiler radar is about 0.5-2 m·s^(-1) smaller than the L-band sounding radar at the high level(>2.5 km),and the effective sample rate of the horizontal wind speed fluctuates between 70%and 90%.Additionally,the effective sample rate of the horizontal wind direction of the wind profiler radar fluctuates growth with increasing altitude.When the atmosphere is moderately unstable,weakly unstable,neutral,or weakly stable,the C^(2)_(n) profiles retrieved by the wind profiler radar and L-band sounding radar agree well with each other at the same time.When the atmosphere is severely unstable or moderately stable,the C^(2)_(n) profiles retrieved by the wind profiler radar and L-band sounding radar show a significant positive correlation(p<0.05),but the two profiles have a large value difference.Precipitation is another important factor that affects the accuracy of the wind profile radar inversion,resulting in a significant increase in the horizontal wind speed inaccuracy.