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GPCC Full Data Reanalysis Version 6.0 at 2.5º: Monthly Land-Surface Precipitation from Rain-Gauges built on GTS-based and Historic Data U. Schneider, A. Becker, P. Finger, A. Meyer-Christoffer, B. Rudolf, and M. Ziese https://doi.org/10.5676/DWD\_GPCC/FD\_M\_V7\_250

Terrestrial Air Temperature and Precipitation: Monthly and Annual Time Series (1950-1999) C. J. Willmott and K. Matsuura http://climate.geog.udel.edu/~climate/html_pages/README.ghcn_ts2.html

Improvements to NOAA's Historical Merged Land-Ocean Surface Temperature Analysis (1880-2006) (http://www.esrl.noaa.gov/psd/data/gridded/data.noaa.ersst.v3.html) T. M. Smith, R. W. Reynolds, T. C. Peterson, and J. Lawrimore https://doi.org/10.1175/2007JCLI2100.1

Interdecadal changes of 30-yr SST normals during 1871-2000 (http://www.esrl.noaa.gov/psd/data/gridded/data.noaa.ersst.v3.html) Y. Xue, T. M. Smith, R. W. and Reynolds https://doi.org/10.1175/1520-0442-16.10.1601

The ERA-40 re-analysis (http://www.cgd.ucar.edu/cas/catalog/reanalysis/ecmwf/era40/daily_sfc.html) S. M. Uppala, P. W. K{\AA}llberg, A. J. Simmons, U. Andrae, V. D. C. Bechtold, M. Fiorino, J. K. Gibson, J. Haseler, A. Hernandez, G. A. Kelly, X. Li, K. Onogi, S. Saarinen, N. Sokka, R. P. Allan, E. Andersson, K. Arpe, M. A. Balmaseda, A. C. M. Beljaars, L. V. D. Berg, J. Bidlot, N. Bormann, S. Caires, F. Chevallier, A. Dethof, M. Dragosavac, M. Fisher, M. Fuentes, S. Hagemann, E. H\'{o}lm, B. J. Hoskins, L. Isaksen, P. A. E. M. Janssen, R. Jenne, A. P. Mcnally, J.-F. Mahfouf, J.-J. Morcrette, N. A. Rayner, R. W. Saunders, P. Simon, A. Sterl, K. E. Trenberth, A. Untch, D. Vasiljevic, P. Viterbo, and J. Woollen https://doi.org/10.1256/qj.04.176