Infrared and microwave SST retrievals are highly complementary but are found to have significant differences that must be addressed if the products are to be combined. Individual products are evaluated using buoy observations to identify any dependence of the retrieval uncertainty on atmospheric forcing. The infrared products are seen to be affected by aerosols, water vapor, and SST while the microwave product is affected by atmospheric stability, wind speed, SST, and water vapor. Applying bias adjustments based on these results reduces the differences between the products