Land Surface Air Temperature Variations Across the Globe Updated to 2019: The CRUTEM5 Data Set

Climatic Research Unit temperature version 5 (CRUTEM5) is an extensive revision of our land surface air data set. We have expanded the underlying compilation monthly records from 5,583 to 10,639 stations, which those with sufficient be used in gridded set has grown 4,842 7,983. Many station also been extended or replaced by series that homogenized national meteorological and hydrological services. improved identification potential outliers these better capture during reference period; avoid classifying some real regional extremes as outliers; reduce trends outlier counts arising climatic warming. Due updates, shows increases density changes anomalies. Nonetheless, global-mean timeseries only slightly modified compared previous versions conclusions are not altered. The standard gridding algorithm comprehensive error model same for version, but we explored alternative removes under-representation high latitude stations. estimated warming about 0.1°C over course whole record. 1861–1900 mean last years 1.6°C using (with a 95% confidence interval errors on individual annual means ?0.11 +0.10°C recent years), while gives change 1.7°C.