基于1988-2017年CCMP数据的浙江沿海海表风速变化及成因

利用1988-2017年CCMP海表风速（Cross Calibrated，Multi-Platform Ocean Surface Wind Velocity）逐月数据、沿海气象站实测风速数据及NCEP/NCAR再分析资料，分析了CCMP海表风速数据在浙江省沿海区域的适用性、浙江省沿海海表风速的年际变化特征及其可能成因。结果表明，利用CCMP海表风速数据与浙江省沿海典型气象站（嵊泗站、普陀站、大陈站、玉环站和洞头站）观测的海表风速进行对比发现，两套资料的风速变化趋势基本一致，且两者风速值偏差较小；利用CCMP海表风速研究浙江沿海风速年际变化特征是合理可信的。CCMP风速距平场的EOF分析结果显示：第一模态的方差贡献率达90.9%，空间场呈一致变化型；第二模态的方差贡献率仅为6.09%，空间场呈偶极子变化型。根据第一模态的方差贡献率和空间场的分布来看，可将浙江沿海全海域风速作为一个整体来研究。1988-2017年浙江沿海CCMP年平均风速序列表明，2002年前后海表风速发生了一次由上升到下降的趋势转变；分析海陆温度变化发现，引起浙江沿海海表风速变化的可能原因是陆地温度上升过快。

Variation and cause of sea surface wind speed in Zhejiang coastal area based on CCMP data from 1988 to 2017

Based on the monthly CCMP sea surface wind speed data,the wind speed data from coastal meteorological stations and the NCEP/NCAR reanalysis data from 1988 to 2017,this paper analyzes applicability of CCMP sea surface wind speed data in coastal areas of Zhejiang Province,and interannual variation characteristics and possible causes of sea surface wind speed in coastal areas of Zhejiang Province.Results show that:by comparing CCMP sea surface wind speed data with sea surface wind velocity data observed by typical coastal meteorological stations(Shengsi,Putuo,Dachen,Yuhuan and Dongtou stations) in Zhejiang Province,the wind speed trends of the two sets of data are basically the same,and the deviation between the two sets of data is small.It is reasonable and credible to study the interannual variation characteristics of wind speed in Zhejiang coastal area by using CCMP sea surface wind speed data.Empirical orthogonal function(EOF) analysis results of CCMP wind speed anomaly field show that:the variance contribution rate of the first mode is 90.9% and the spatial field shows a consistent pattern;the variance contribution rate of the second mode is 6.09% and the spatial field shows a dipole variation pattern.According to the variance contribution rate of the first mode and its spatial field distribution,the wind speed in the whole coastal area of Zhejiang Province can be studied as a whole.The annual average wind speed series of Zhejiang coastal CCMP from 1988 to 2017 shows that the coastal sea surface wind speed has changed from rising to falling before and after 2002.The analysis of land-sea temperature shows that the possible reason for the change of sea surface wind speed in Zhejiang coastal area is that the land temperature rises too fast.