Evaluation of Sea Surface Salinity Observed by Aquarius
[13-Nov-2013] Abe, H. and Ebuchi, N.
Presented at the 2013 Aquarius/SAC-D Science Team Meeting
The sea surface salinity (SSS) observed by Aquarius was validated by using various sources of ocean surface salinity observations including Argo floats. The Level-2 SSS products retrieved by different algorisms (standard V2.2, CAP V2.3.1 and RSS V3) were compared with the in-situ salinity data. The root-mean-square (rms) difference was 0.55 psu for the CAP V2.3.1 product, while the other products showed smaller values of 0.41 psu. However, the amplitude of the ascending-descending bias, typically found in the Southern Ocean, was considerably reduced (0.13 psu) in the CAP V2.3.1 product compared to the other products (0.27 psu). The Level-3 monthly SSS products retrieved by the CAP V2.3.1 algorism showed good agreement with the monthly-averaged SSS fields from the JAMSTEC optimal interpolation system with a value of 0.21 psu, which is very close to the mission goal, while the other products exhibited larger values (~0.23 psu). The standard product (V.2.2) exhibited systematic negative bias in the area near the equator and the Asian Pacific and eastern North Atlantic areas, while such negative biases were mitigated substantially in the CAP V2.3.1 product.