Research On Data Fusion Of Sea Surface Wind In China's Offshore Based On Optimal Interpolation Method

High-resolution and spatial-temporal continuous sea-surface wind field can effectively improve the accuracy and timeliness of ocean forecasting.The interpolation of the ASCAT orbital wind field and the ERA-Interim reanalysis wind field in offshore China through optimal interpolation method can effectively improve the accuracy of reanalysis wind field and form a high-precision,high-resolution spatial-temporal continuous oversea coverage wind field dataset,it will have important implications for offshore area research and ocean forecasting.This article mainly carried out the following work:First,using the buoy data to evaluate the quality of the ASCAT orbital wind field and ERA-Interim reanalysis wind field for a full year of 2015,it can be found that the consistency of the ASCAT wind speed with the buoy in China is better than that of the ERA-Interim.The root mean square error of ASCAT is 2.15 m/s,the correlation coefficient is 0.81,the root mean square error of ERA-Interim reanalysis is 2.48 m/s,and the correlation coefficient is 0.72.The ASCAT and ERA-Interim are basically consistent with the buoy wind direction.The root mean square error of ASCAT wind direction is 49.48°,and the correlation coefficient is 0.9.The root mean square error and correlation coefficient of ERA-Interim are 46.83° and 0.91,respectively.Affected by the geometrical distribution of the coastline,the consistency of the ASCAT and ERA-Interim wind fields with the buoys in the Bohai Sea,the Yellow Sea is not as good as that in the East China Sea and the South China Sea.Secondly,the research on the optimal interpolation of sea surface wind field fusion was carried out to determine the relevant parameters of interpolation,and the ASCAT orbital wind field and ERA-Interim reanalysis wind field in 2015 were interpolated.Finally,using buoy data and CCMP wind fusion products to conduct a preliminary inspection of the optimally interpolated fusion wind field and analyze its accuracy improvement relative to the ERA-Interim reanalysis wind field,it can be found that the consistency of the fusion product and the buoy is better than that of the ERA-Interim wind field.The root mean square error of the wind speed is 2.05m/s,which is about 15% smaller than that of the ERA-Interim wind field,and the root mean square error of the wind direction is 48.81°,which has no obvious improvement.At the same time,the accuracy of the integrated wind field also differs in different sea areas,and the consistency between the Bohai Sea,the Yellow Sea,and the buoy observation is not as good as that of the East China Sea and the South China Sea.The root mean square error of the wind speed and the wind speed error characteristics of each wind level are compared with the ERA-Interim wind field in each month.The CCPM wind product tests on the interpolated fusion wind field also found that the two wind fields are basically similar except for some areas along the coast.Therefore,the ASCAT orbital wind field plays an important role in constructing a highly-precision wind field.The interpolation of the ASCAT orbital wind field and the ERA-interim reanalysis wind field through optimal interpolation can effectively improve the accuracy of the wind field,and obtain a continuous sea surface wind field data set.