Two new high resolution sea surface temperature (SST) analysis products have been developed by NOAA NCDC using optimum interpolation (OI). The analyses have a spatial grid resolution of 0.25 degrees and temporal resolution of 1 day. One product uses Advanced Very High Resolution Radiometer (AVHRR) infrared satellite SST data. The other uses AVHRR and Advanced Microwave Scanning Radiometer (AMSR) on the NASA Earth Observing System satellite SST data. Both products also use in situ data from ships and buoys and include a large-scale adjustment of satellite biases with respect to the in situ data. Two products are needed because there is an increase in signal variance when AMSR became available in June 2002 due to its near all-weather coverage.