Extended Data Fig. 4: Comprehensive assessment of reconstruction skill.

a,b, Violin-and-box plots (‘voxplots’) summarizing ΔSLP reconstruction skill in terms of correlation coefficient (r), RMSE and RE (ref. ¹³²). These voxplots show the skill tests for the ΔSLP reconstruction ensemble shown in the main text. All tests were performed on all 4,800 ΔSLP reconstruction ensemble members. Voxplots show the distribution of scores; boxes shows median and interquartile range (IQR), whiskers show IQR × 1.5, points show outliers. Each individual ensemble member was assessed against ΔSLP used to train that particular ensemble member, that is, ΔSLP calculated from HadSLP, ICOADS or ERA-20C. a, Skill scores split according to the gridded SLP product used to calculate the ΔSLP training data. b, Skill scores split according to the reconstruction method. c, Running 30-year correlations between the ensemble medians for each possible combination of reconstruction method and gridded SLP product used to calculate the ΔSLP training data. Thick black line shows the median running correlation. Lines are coloured according to unique combinations of reconstruction method.