Chinese Journal of Oceanology and Limnology

, Volume 33, Issue 4, pp 1072–1084 | Cite as

A method for correcting regional bias in SMOS global salinity products

  • Xiaolin Tong (佟晓林)
  • Zhenzhan Wang (王振占)
  • Qingxia Li (李青侠)Email author


Soil Moisture and Ocean Salinity (SMOS) Level 3 (L3) sea surface salinity (SSS) products are provided by the Barcelona Expert Centre (BEC). Strong biases were observed on the SMOS SSS products, thus the data from the Centre Aval de Traitement des Données SMOS (CATDS) were adjusted for biases using a large-scale correction derived from observed differences between the SMOS SSS and World Ocean Atlas (WOA) climatology data. However, this large-scale correction method is not suitable for correcting the large gradient of salinity biases. Here, we present a method for the correction of SSS regional bias of the monthly L3 products. Based on the stable characteristics of the large SSS biases from month to month in some regions, corrected SMOS SSS maps can be obtained from the monthly mean values after removing the regional biases. The accuracy of the SMOS SSS measurements is greatly improved, especially near the coastline, at high latitudes, and in some open ocean regions. The SMOS and ISAS SSS data are also compared with Aquarius SSS to verify the corrected SMOS SSS data. The correction method presented here only corrects annual mean biases. The measurement accuracy of the SSS may be improved by considering the influence of atmospheric and ocean circulation in different seasons and years.


ocean salinity microwave radiometry sea surface Soil Moisture and Ocean Salinity (SMOS) 


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Copyright information

© Chinese Society for Oceanology and Limnology, Science Press and Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Xiaolin Tong (佟晓林)
    • 1
    • 2
    • 3
  • Zhenzhan Wang (王振占)
    • 2
  • Qingxia Li (李青侠)
    • 1
    Email author
  1. 1.Department of Electronics and Information EngineeringHuazhong University of Science and TechnologyWuhanChina
  2. 2.Key Laboratory of Microwave Remote Sensing, National Space Science Center/Center for Space Science and Applied ResearchChinese Academy of SciencesBeijingChina
  3. 3.School of Physics and ElectronicsHenan UniversityKaifengChina

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