Evaluation of sea surface temperature from HY-2 scanning microwave radiometer

The HY-2 (Haiyang-2) satellite was launched in August 2011. The scanning microwave radiometer (RM) onboard HY-2 has low frequency channels with the capability for sea surface temperature (SST) observations from space. The HY-2 RM L2A SST products are evaluated. The L2A products are compared with WindSat, AMSR2 SST products and in situ SST measurements by buoy. The results indicate a standard deviation around 2 ^oC with fluctuated bias. The comparisons of the daily ascending passes between HY-2 RM and WindSat in January 2013 show the bias of each day is between 0.12 ^oC and 0.75 ^oC and the standard deviation is between 1.75 ^oC and 2.97 ^oC. For descending passes, the bias is from -0.51 ^oC to 0.25 ^oC and standard deviation from 1.56 ^oC to 2.58 ^oC. The statistics of the matchups between HY-2 RM and buoy SST data during the period of August 2012 to December 2014 shows a bias of -0.29 ^oC and standard deviation of 1.94 ^oC. The relationships between SST difference and the surface parameters such as wind speed and SST are investigated.