HadISST Average Sea Surface Temperature, 1°, Global, Monthly, 1870-present

The Met Office Hadley Centre's sea ice and sea surface temperature (SST) data set, HadISST1, replaces the Global sea Ice and Sea Surface Temperature (GISST) data sets, and is a unique combination of monthly globally-complete fields of SST and sea ice concentration on a 1 degree latitude-longitude grid from 1870 to date. WARNING: 10 March 2016: A detailed analysis of HadISST (https://ir.library.oregonstate.edu/xmlui/handle/1957/58385) has identified a number of problems, some of which might limit the utility of the dataset for certain scientific applications, particularly where high resolution SST data or spatial gradients of SST are required. Thanks to Dudley Chelton and Craig Risien for bringing this to our attention and their detailed analysis. The SST data are taken from the Met Office Marine Data Bank (MDB), which from 1982 onwards also includes data received through the Global Telecommunications System (GTS). In order to enhance data coverage, monthly median SSTs for 1871-1995 from the Comprehensive Ocean-Atmosphere Data Set (COADS) (now ICOADS) were also used where there were no MDB data. HadISST1 temperatures are reconstructed using a two stage reduced-space optimal interpolation procedure, followed by superposition of quality-improved gridded observations onto the reconstructions to restore local detail. SSTs near sea ice are estimated using statistical relationships between SST and sea ice concentration. Data restrictions: for academic research use only. Updates and supplementary information will be available from http://www.hadobs.org