基于4种再分析资料的中国近海风速特征分析

Characteristics of Sea Surface Wind over China Seas Based on Four Reanalysis Data Sets

基于4种高分辨率海面风场产品(CCMP、CFSR、ERA-interim和JRA55),探究1988—2015年期间中国近海风速的年际变化特征。通过将4种分析/再分析数据插值得到的10,m高度风速与中国近海海洋站和气象站风速观测资料进行比较,得出如下结论:(1)JRA55和ERA-int的风速相比CCMP和CFSR更接近实测值,CCMP和CFSR的风速差异较大,无法反映实际情况;(2)4种数据中JRA55的平均风速偏差(Bias)和均方根误差(RMSE)最小,分别为0.220ms-1和0.964ms-1,但4种数据整体差距不大;(3)Taylor综合统计分析发现在4种数据中,ERA再分析数据最接近于观测值,JRA55数据在中国近海风速代表性较好。

This study investigates the long-term changes of sea surface wind over China Seas from 1988 to 2015. 10-meter wind speeds from four gridded datasets with high resolution in both space and time were used, including Cross-Calibrated Multi-Platform （CCMP） data set, NCEP climate forecast system reanalysis （CFSR）data set, ERA-interim （ERA-int） reanalysis data set and Japanese 55-year （JRA55）reanalysis data set. By comparing wind speed from the analysis/reanalysis datasets with observations from ten marine stations, it is found that： （1）the wind speeds of JRA55 and ERA-int are more accurate than those of CCMP and CFSR, which is closer to the observation, and the wind speed difference from the CCMP and CFSR is too big to reflect the real situation. （2）the calculated mean wind speed Bias and root-mean-squareerror （RMSE）are similar for the four datasets, the lowest value （0.220 ms-1 and 0.964 ms-1） was obtained from the JRA55. （3）comprehensive statistical analysis leads us to conclude that among the four analyzed datasets, the ERA-Interim reanalysis is the closest to observe wind speed over the China Seas, while JRA55 is another valid alternative for reliable representations of the observation.