Current Tropical Pacific Sea Surface Temps - degrees C
Current 3 month animation —
Analysis Description and Recent Reanalysis
The optimum interpolation ( OI ) sea surface temperature ( SST ) analysis is produced weekly on a one-degree grid. The analysis uses in situ and satellite SSTs plus SSTs simulated by sea ice cover. Before the analysis is computed, the satellite data is adjusted for biases using the method of Reynolds (1988) and Reynolds and Marsico (1993). A description of the OI analysis can be found in Reynolds and Smith (1994). The bias correction improves the large scale accuracy of the OI.
In November 2001, the OI fields were recomputed for late 1981 onward. The new version will be referred to as OI.v2.
The most significant change for the OI.v2 is the improved simulation of SST obs from sea ice data following a technique developed at the UK Met Office. This change has reduced biases in the OI SST at higher latitudes. Also, the update and extension of the International Comprehensive Ocean-Atmosphere Data Set ( ICOADS ) has provided us with improved ship data coverage through 1997, reducing the residual satellite biases in otherwise data sparse regions. For more details, see Reynolds, et al (2002).
Sea Surface Temperature Charts
A real-time global sea surface temperature ( SST ) analysis has been developed by Richard Reynolds from the Climate Modeleling Branch of the National Centers for Environmental Prediction (NCEP). A monthly one degree global SST climatology was constructed. This climatology was derived from monthly optimum interpolation ( OI ) SST analyses with an adjusted base period of 1950-79. The areal coverage is roughly between 40S and 60N globally. These analyses were based on ship and buoy SST data supplemented by satellite SST retrievals. In addition, SST climatology was derived from monthly analyses using sea-ice coverage data over a 12-year period (1982-93). The one degree climatology resolves equatorial upwelling and fronts.
The optimum interpolation ( OI ) SST analysis is produced weekly on a one-degree grid. The analysis uses buoy and ship data, satellite SST data, and SST's simulated by sea-ice coverage. Before the analysis is computed, the satellite data is adjusted for biases using the method described by Reynolds (1988) and Reynolds and Marsico 1993). A description of the analysis can be found in Reynolds and Smith (1994).
International Comprehensive Ocean-Atmosphere Data Set
The International Comprehensive Ocean-Atmosphere Data Set (ICOADS) offers surface marine data spanning the past three centuries, and simple gridded monthly summary products for 2° latitude x 2° longitude boxes back to 1800 ( and 1°x1° boxes since 1960 ) — these data and products are freely distributed worldwide. As it contains observations from many different observing systems encompassing the evolution of measurement technology over hundreds of years, ICOADS is probably the most complete and heterogeneous collection of surface marine data in existence.
The oceanographic community has ignored the fundamental differences between skin and bulk SST for many years trying to explain away variability found in the buoy calibrated satellite SSTs as atmospheric variability. While it is true that the atmosphere is the source of the greatest errors in the satellite SST measurements, the bulk-skin SST difference represents an error source that can be corrected through the use of in situ skin SST measurements. There are a number of basic issues that must be considered before any particular SST validation plan becomes meaningful.