Global Mapping | Climate at a Glance

Global temperature anomaly data come from NOAA's Global Surface Temperature Analysis (NOAAGlobalTemp), which uses comprehensive data collections of increased global coverage over land (Global Historical Climatology Network-Monthly) and ocean (Extended Reconstructed Sea Surface Temperature) surfaces. These datasets have data from 1850 to the present. The land and ocean datasets are blended into a single product to produce the combined global land and ocean temperature anomalies. The available timeseries of global-scale temperature anomalies are calculated with respect to the 1901-2000 average, while the mapping tool displays global-scale temperature anomalies with respect to the 1991-2020 base period. For more information on these anomalies, please visit Global Surface Temperature Anomalies.