HadISST: Global sea-ice and sea surface temperature

HadISST consists of monthly mean fields of sea-surface temperature (SST, degrees C) and sea-ice concentration from 1870 through to two months before the current month. Missing values have been filled in a statistically optimal way. HadISST therefore has global coverage, and is available on a 1 ° latitude x 1 ° longitude grid.

Sea-ice concentration fields from different sources were analysed to make them as consistent as possible through time. Care should be taken when using the sea-ice concentration data, particularly in the southern hemisphere where there is no realistic interannual variability in sea ice prior to 1973.

More about HadISST

Latest month anomaly field

This map denotes anomalies in SST and fractional sea-ice concentration for the most recent available month relative to the 1961-90 climatology values. The El Niño Southern Oscillation originates in the equatorial Pacific off the coast of South America. If the SST anomalies in this region are warm then an El Niño event is currently under way.

Latest month absolute field

Absolute temperature fields from HadISST are used by the Met Office Hadley Centre and other climate modelling groups to provide lower boundary ocean conditions to atmosphere-only climate model runs. These have advantages over fully coupled models (that include a dynamical ocean component) for several (but not all) applications. This is because the timing and strength of many oceanic phenomena which affect the atmosphere, as well as the long-term response to human and natural influences on the climate system, are given by HadISST.