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2012GL054769ts01.txtplain text document5KText S1. Radiative forcing used in real-time forecasts until 2010.
2012GL054769ts02.txtplain text document4KText S2. Further details of statistical methods used in 2000-2010.
2012GL054769ts03.txtplain text document2KText S3. Cross validation methodology for testing intrinsic prediction skill.
2012GL054769ts04.txtplain text document3KText S4. A small but significant warm bias in issued global temperature forecasts.
2012GL054769ts05.txtplain text document1KText S5. Use of the AMO as a predictor.
2012GL054769ts06.txtplain text document4KText S6. Testing the influence of individual predictors.
2012GL054769ts07.docWord document28KSurface temperature data sets used to train statistical methods and verify forecasts.
2012GL054769ts08.docWord document40KInfluences of persistence and of removing predictors one at a time on cross validated hindcast skill, 1891-2011. Interannual correlation is not shown for 2000-2011 as the period is too short.
2012GL054769fs01.tifTIFF image353KReduction in the Arctic station coverage in HadCRUT3 in the first decade of the 21st century. HadCRUT3 station distribution in 2005-2009 is compared to that in 1990-1999. Blue: common stations; orange: stations not available in 2005-2009; green: stations newly available in 2005-2009.
2012GL054769fs02.tifTIFF image386KReanalysis temperature anomalies showing a very rapid recent warming in the central Arctic. Temperature anomalies in the Arctic region relative to 1961-1990 for 2001-2010 are calculated from the Twentieth Century Reanalysis (Compo et al, 2011).
2012GL054769fs03.tifTIFF image52KCross correlation of annual AMO and detrended GST, 1891-2011. GST is the average of HadCRUT3, GISS and NCDC data. The raw GST cross correlation curve retains the GST trend.
2012GL054769fs04.tifTIFF image102KThe influence time on cross validated hindcasts of removing selected individual predictors one at time, together with cross validated methods using persistence and ENSO alone,1891-2011. Major tropical volcanic influences are shown by dates in Fig S4b (2012GL054769-fs04.tiff).
2012GL054769readme.txtplain text document5KReference list for Auxiliary Information

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