摘要
针对SMOS和Aquarius海表盐度误差分析没有区分不同空间频谱信噪特征的问题,基于6种主要的遥感盐度分析产品,根据定性图像、纬向波数谱、均方根误差等指标,分析产品的有效分辨率并探讨其原因机制。研究表明:CATDS-0.25°分析产品所描述的盐度场中小尺度结构失真,其较高谱能量密度在热带海域以噪音为主,而在西边界流等海域以信号为主;BEC-L3-0.25°有着较小的均方根误差、清晰的盐度图像、显著的中尺度能量,最适于描绘中尺度(25～100km)盐度特征;BEC-L4-0.25°被奇异谱分析方法过度平滑了盐度场;Aquarius-V2-1.00°通过局部平滑处理,在描述大尺度(>100km)盐度现象方面表现较好;Aquarius-CAP-1.00°通过主动-被动联合算法(CAP)减小了均方根误差,但图像中卫星轨道形态明显;CATDS-1.00°的图像形态、能量分布和误差特征与AquariusV2-1.00°相当。这些结论可为用户正确使用产品进行地球物理学研究提供参考。
The effective resolutions of six remotely sensed reanalysis products of sea surface salinity(SSS)from the soil moisture and ocean salinity(SMOS)and Aquarius/SAC-D missions were studied,in terms of the qualitative map,zonal wavenumber spectra,and root mean square(RMS)error.The mechanisms behind their differences also are studied.It suggests that the CATDS-0.25° reanalysis is unable to capture the smallscale structures in SSS and performs the worst in representing spatial variability in SSS.Its higher spectral energy is mostly a reflection of noises in the tropics while those in regions such as along the western boundary flows are signals.The BEC-L3-0.25° reanalysis,which has small RMS errors,clear salinity maps,and remarkable mesoscale energy,is the best fit for portraying mesoscale(25-100km)SSS features.The SSS in the BEC-L4-0.25° reanalysis is overly attenuated by its singularity analysis remapping method.The AquariusV2-1.00° reanalysis,with an additional smoothing procedure,performs well in depicting large-scale(>100km)salinity phenomena.The Aquarius-CAP-1.00° reanalysis generates the smallest RMS errors benefiting from its combined active-passive(CAP)algorithm,however,and leads to a somewhat noisy,artificial pattern with unreasonable along-track strips.The CATDS-1.00° reanalysis is roughly equivalent to the Aquarius-V2-1.00° in terms of pattern,energy,and error features.
作者
陈建
程锐
刘娟
王辉赞
鲍森亮
闫恒乾
CHEN Jian;CHENG Rui;LIU Juan;WANG Hui-zan;BAO Sen-liang;YAN Heng-qian(Beijing Institute of Applied Meteorology,Beijing 100029,China;State Key Laboratory of Geo-Information Engineering,Xi’an 710054,China;Institute of Meteorology and Oceanography,National University of Defense Technology,Changsha 410073,China)
出处
《海洋学研究》
CSCD
北大核心
2018年第4期17-27,共11页
Journal of Marine Sciences
基金
国家自然科学基金项目资助(41706021).
