中法海洋卫星散射计近海岸海面风场反演研究  

Coastal wind retrieval from the China-France oceanography satellite scatterometer

作　　者：林文明 郎姝燕[2,3] 赵晓康 刘建强 李秀仲[1] Lin Wenming;Lang Shuyan;Zhao Xiaokang;Liu Jianqiang;Li Xiuzhong(School of Marine Sciences,Nanjing University of Information Science and Technology,Nanjing 210044,China;National Satellite Ocean Application Service,Beijing 100081,China;Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou),Guangzhou 511458,China)

机构地区：[1]南京信息工程大学海洋科学学院,江苏南京210044 [2]国家卫星海洋应用中心,北京100081 [3]南方海洋科学与工程广东省实验室(广州),广东广州511458

出　　处：《海洋学报》2021年第10期115-123,共9页

基　　金：国家重点研发计划(2016YFC1401005);国家自然科学基金青年基金(41706197);南方海洋科学与工程广东省实验室(广州)人才团队引进重大专项(GML2019ZD0302)。

摘　　要：中法海洋卫星散射计(CSCAT)使用扇形波束旋转扫描体制,能够以多角度测量同一海面的雷达后向散射系数,并具有空间分辨率较高的特点。这为近海岸海面风场反演提供了新的机遇。本文介绍了CSCAT近海岸海面风场处理的主要流程和关键技术。特别地,在风场反演之前,利用一种矩形窗算术平均的方法将L1B级的高分辨率条带数据组合平均到相应的风矢量单元中,从而实现近海岸风场反演的快速预处理。通过对比CSCAT、欧洲先进散射计(ASCAT)以及美国QuikSCAT的近海岸风场,发现CSCAT风场的质量在离岸40 km以外区域具有良好的一致性,而在离岸40 km以内显著恶化。分析表明,CSCAT近海岸区域风场统计特征恶化的原因可能是由潜在的海冰污染引起的。总体而言,CSCAT的近海岸风场与模式背景风场和浮标风场都具有良好的一致性。The scatterometer onboard China-France oceanography satellite(CFOSAT)uses rotating fan beams to measure sea surface radar backscatter values at different incidence and azimuth angles.The backscatter measurements of CFOSAT scatterometer(CSCAT)are with relatively high spatial resolution.Therefore,it presents unprecedented opportunities for retrieving offshore wind fields.This paper introduces the main procedures as well as the key techniques of the coastal wind retrieval for CSCAT.In particular,a box-window is used to aggregate the highresolution backscatters(namely slices in the level 1B data)into a certain wind vector cell(WVC)before performing the wind inversion.The coastal winds derived from the advanced scatterometer(ASCAT)and the QuikSCAT scatterometer are then used to verify the results of CSCAT coastal wind retrieval.It shows that the CSCAT winds are of good quality over the sea surface with offshore distance larger than 40 km,but degrades rapidly in quality for WVCs with offshore distance below 40 km.Further analysis indicates that the degraded statistical scores are mainly caused by some outliers that may be contaminated by the sea ice.In general,the CSCAT offshore winds are in good agreement with both the model forecasts and the buoy winds.

关 键 词：中法海洋卫星 散射计 近海岸 风场反演 统计特征 

分 类 号：P715.7[天文地球—海洋科学]