Climate at a Glance

Global Data Information

Global temperature anomaly data come from NOAA's Merged Land Ocean 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 1880 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 20th century 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.