Cite this paper:
Huipeng WANG, Junqiang SONG, Chengwu ZHAO, Xiangrong YANG, Hongze LENG, Nan ZHOU. Validation of the multi-satellite merged sea surface salinity in the South China Sea[J]. Journal of Oceanology and Limnology, 2023, 41(6): 2033-2044

Validation of the multi-satellite merged sea surface salinity in the South China Sea

Huipeng WANG1, Junqiang SONG1, Chengwu ZHAO1, Xiangrong YANG1, Hongze LENG1, Nan ZHOU2
1 College of Meteorology and Oceanography, National University of Defense Technology, Changsha 410073, China;
2 Troop 61741, PLA, Beijing 100094, China
Sea surface salinity (SSS) is an essential variable of ocean dynamics and climate research. The Soil Moisture and Ocean Salinity (SMOS), Aquarius, and Soil Moisture Active Passive (SMAP) satellite missions all provide SSS measurements. The European Space Agency (ESA) Climate Change Initiative Sea Surface Salinity (CCI-SSS) project merged these three satellite SSS data to produce CCI L4 SSS products. We validated the accuracy of the four satellite products (CCI, SMOS, Aquarius, and SMAP) using in-situ gridded data and Argo floats in the South China Sea (SCS). Compared with in-situ gridded data, it shows that the CCI achieved the best performance (RMSD: 0.365) on monthly time scales. The RMSD of SMOS, Aquarius, and SMAP (SMOS: 0.389; Aquarius: 0.409; SMAP: 0.391) are close, and the SMOS takes a slight advantage in contrast with Aquarius and SMAP. Large discrepancies can be found near the coastline and in the shelf seas. Meanwhile, CCI with lower RMSD (0.295) perform better than single satellite data (SMOS: 0.517; SMAP: 0.297) on weekly time scales compared with Argo floats. Overall, the merged CCI have the smallest RMSD among the four satellite products in the SCS on both weekly time scales and monthly time scales, which illustrates the improved accuracy of merged CCI compared with the individual satellite data.
Key words:    sea surface salinity (SSS)|South China Sea (SCS)|Argo|multi-satellite merged data|validation   
Received: 2022-04-11   Revised:
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Akhil V P, Vialard J, Lengaigne M et al.2020.Bay of Bengal Sea surface salinity variability using a decade of improved SMOS re-processing.Remote Sensing of Environment, 248:111964,
Balaguru K, Chang P, Saravanan R et al.2012.Ocean barrier layers' effect on tropical cyclone intensification.Proceedings of the National Academy of Sciences of the United States of America, 109(36):14343-14347,
Bao S L, Wang H Z, Zhang R et al.2019.Comparison of satellite-derived sea surface salinity products from SMOS, Aquarius, and SMAP.Journal of Geophysical Research, 124(3):1932-1944,
Boutin J, Chao Y, Asher W E et al.2016.Satellite and in situ salinity:understanding near-surface stratification and subfootprint variability.Bulletin of the American Meteorological Society, 97(8):1391-1407,
Boutin J, Reul N, Koehler J et al.2021.Satellite-based sea surface salinity designed for ocean and climate studies.Journal of Geophysical Research, 126:e2021JC017676,
Boutin J, Vergely J L, Marchand S et al.2018.New SMOS sea surface salinity with reduced systematic errors and improved variability.Remote Sensing of Environment, 214:115-134,
Boyer T P, Levitus S.2002.Harmonic analysis of climatological sea surface salinity.Journal of Geophysical Research, 107(C12):8006,
Chen B, Xu Z X, Ya H Z et al.2019.Impact of the water input from the eastern Qiongzhou Strait to the Beibu Gulf on Guangxi coastal circulation.Acta Oceanologica Sinica, 38(9):1-11,
Droghei R, Buongiorno Nardelli B, Santoleri R.2018.A new global sea surface salinity and density dataset from multivariate observations (1993-2016).Frontiers in Marine Science, 5:84,
Du Y, Zhang Y H.2015.Satellite and Argo observed surface salinity variations in the tropical Indian Ocean and their association with the Indian Ocean dipole mode.Journal of Climate, 28(2):695-713,
Good S A, Martin M J, Rayner N A.2013.EN4:Quality controlled ocean temperature and salinity profiles and monthly objective analyses with uncertainty estimates.Journal of Geophysical Research, 118(12):6704-6716,
Hackert E, Ballabrera-Poy J, Busalacchi A J et al.2011.Impact of sea surface salinity assimilation on coupled forecasts in the tropical Pacific.Journal of Geophysical Research, 116(C5):C05009,
Hlywiak J, Nolan D S.2019.The influence of oceanic barrier layers on tropical cyclone intensity as determined through idealized, coupled numerical simulations.Journal of Physical Oceanography, 49(7):1723-1745,
Hu J Y, Kawamura H, Hong H S et al.2000.A review on the currents in the South China Sea:seasonal circulation, South China Sea warm current and Kuroshio intrusion.Journal of Oceanography, 56(6):607-624,
Kao H Y, Lagerloef G S E, Lee T et al.2018.Assessment of Aquarius sea surface salinity.Remote Sensing, 10(9):1341,
Li C J, Zhao H, Li H P et al.2015.Assessment of SMOS and Aquarius/SAC-D salinity data accuracy in the South China Sea:three statistical methods.In:Proceedings of 2015 IEEE International Geoscience and Remote Sensing Symposium.IEEE, Milan, Italy.p.954-957,
Li Y H, Liu T T, Shang S L.2016.On the performance of Aquarius sea surface salinity V4 product in the South China Sea.Journal of Xiamen University (Natural Science), 55(4):522-530.(in Chinese with English abstract)
Liu H, Wei Z X.2021.Intercomparison of global sea surface salinity from multiple datasets over 2011-2018.Remote Sensing, 13(4):811,
Liu Y X, Cheng L J, Pan Y Y et al.2022.Climatological seasonal variation of the upper ocean salinity.International Journal of Climatology, 42(6):3477-3498,
Lukas R, Lindstrom E.1991.The mixed layer of the western equatorial Pacific Ocean.Journal of Geophysical Research, 96(S01):3343-3357,
Menezes V V.2020.Statistical assessment of sea-surface salinity from SMAP:Arabian Sea, Bay of Bengal and a promising red sea application.Remote Sensing, 12(3):447,
Pang S S, Wang X D, Foltz G et al.2020.Modulation of June rainfall in India by winter salinity barrier layer in the Bay of Bengal,
Qi J F, Du Y, Chi J W et al.2022.Impacts of El Niño on the South China Sea surface salinity as seen from satellites.Environmental Research Letters, 17(5):054040,
Qin S S, Wang H, Zhu J et al.2020.Validation and correction of sea surface salinity retrieval from SMAP.Acta Oceanologica Sinica, 39(3):148-158,
Ren Y Z, Dong Q, He M X.2015.Preliminary validation of SMOS sea surface salinity measurements in the South China Sea.Chinese Journal of Oceanology and Limnology, 33(1):262-271,
Reul N, Grodsky S A, Arias M et al.2020.Sea surface salinity estimates from spaceborne L-band radiometers:an overview of the first decade of observation (2010-2019).Remote Sensing of Environment, 242:111769,
Stammer D, Martins M S, Köhler J et al.2021.How well do we know ocean salinity and its changes? Progress in Oceanography, 190:102478,
Vinogradova N, Lee T, Boutin J et al.2019.Satellite salinity observing system:recent discoveries and the way forward.Frontiers in Marine Science, 6:243,
Wang X X, Yang J H, Zhao D Z et al.2013.Assessment of Aquarius/SAC-D salinity data accuracy in the South China Sea.Journal of Tropical Oceanography, 32(5):23-28.(in Chinese with English abstract)
Yan Y F, Li L, Wang C Z.2017.The effects of oceanic barrier layer on the upper ocean response to tropical cyclones.Journal of Geophysical Research, 122(6):4829-4844,
Yi D L, Melnichenko O, Hacker P et al.2020.Remote sensing of sea surface salinity variability in the South China Sea.Journal of Geophysical Research, 125(12):e2020JC016827,
Zeng L L, Liu W T, Xue H J et al.2014.Freshening in the South China Sea during 2012 revealed by Aquarius and in situ data.Journal of Geophysical Research, 119(12):8296-8314,
Zhu J S, Huang B H, Zhang R H et al.2014.Salinity anomaly as a trigger for ENSO events.Scientific Reports, 4(1):6821,
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