北京地区风廓线雷达水平风资料评价分析

Comparison of Wind Profiler Wind Products against Radiosonde Measurements in Beijing

做好风廓线雷达水平风探测数据与气球探空的对比分析,对于更进一步用好这种仪器十分必要。采用北京南郊2014-2018年5年探空资料,对该站同期风廓线雷达水平风资料从总体平均、早中晚、不同天空状况及平均年变化等方面进行对比分析。结果表明:①5年平均均方根误差U分量在2.2~5.0m/s之间,V分量在2.3~3.6m/s之间,均在850hPa高度最小。平均误差U分量均为负,表明近5年风廓线雷达所测U分量比气球探空的偏小;且随高度其绝对值是增大的。V分量仅在700hPa高度为负,也在该高度最小。U、V分量分别在500hPa和850hPa高度相似程度最好。5年综合来看,850和700hPa高度风与气球探空更接近。②中午误差低于早晚,这与中午大气湍流比较强盛有关。③云量较多时误差相对较小,云量少时(特别是晴空)误差较大,反映出这种仪器对湿度比较敏感。④夏季或夏半年U、V分量与气球探空的差异较小、相似程度好,尤以6或7月最突出;冬季或冬半年差异较大、相似程度较差,尤以12或1月明显。这在实际业务和科研使用时需注意。

It is necessary for further making use of the measurements to conduct the comprehensive comparison of wind profiler horizontal wind against radiosonde data.Based on the 5-year collocated wind speed data from radiosondes and wind profilers in Beijing,the wind profiler data are carefully analyzed,including total average,diurnal and annual variations,different sky conditions.The results show that the root mean square error of 5-year average U-component was from 2.2 to 5.0 m/s,the V-component from 2.3 to 3.6 m/s,and the U-component and V-component minimum deviation occurred at 850 hPa.The Ucomponent average error of different heights was negative,which indicates the wind profiler U-component wind speed is smaller than that of balloon sounding,and the absolute value of error increased with height.The V-component average errors were negative only at 700 hPa.The similarity of U-component at 500 hPa was the best and that of Vcomponent wind at 850 hPa was the best.On average,the wind profiler wind was closer to balloon sounding at 850 hPa and 700 hPa.The errors in the U and Vcomponents at 14:00 were relatively smaller than those at 08:00 and 20:00,which was related to the strong atmospheric turbulence at noon.The errors were relatively small when the amount of clouds was large,and large when the amount of clouds was small(especially in clear sky).which indicates the wind profiler is sensitive to humidity.The U and V components have little difference and good similarity with balloon sounding in summer or summer half year,especially in June and July,and large difference and bad similarity in winter or winter half year,especially in December and January.This should be paid enough attention in forecast operation use and scientific researches.