Surface air temperature and pressure anomalies in the Northern Hemisphere during the 20th century: observations and reanalyses

摘要

Observational data and three reanalysis datasets on surface air temperature and sea level pressure anomalies inthe Northern Hemisphere during the 20th century are compared with a focus on the Arctic region. The evolution oftemperature anomalies, spatial distribution of temperature trends and changes of the atmospheric centers of action (ACA)are analyzed. It is found that changes in temperature and pressure in the Northern Hemisphere extratropics throughoutthe 20th century have been more realistically reproduced by the European reanalyses, most successfully in CERA20Creanalysis. Reanalysis NOAA20C reproduces the evolution and patterns of surface air temperature and sea level pressureanomalies changes significantly worse throughout the 20th century.