The long-term 20th century re-analysis features over the North Atlantic-Eurasia region

The currently available long-term 20th century re-analysis (20CR) was applied to studying particular features of the intra-seasonal and multi-annual climate variability over the Atlantic-Eurasian domain. This re-analysis shows a good consistency with observations and appears to be the sufficient tool to study surface air temperature (SAT) and geopotential height on daily to seasonal scales over Eurasia. However, a disagreement was found in the mean daily values: an underestimation in spring and overestimation in summer. The cold period of the year is characterized by the least discrepancy between reanalysis and observations. The appropriate quality of 20CR seems to be reliable before 1950 and after 1950, and it is based on the comparison analysis of the blocking events and the mean annual integral meridional drift transport. The resulting linear trends of 20CR for 140 years show a significant positive tendency over the globe, except of large parts of Europe and northeastern Pacific/North Atlantic, where a natural climate variability is prominent.