Fig. 2
From: Ensemble size versus bias correction effects in subseasonal-to-seasonal (S2S) forecasts
Temporal evolution of the MSSSs for (left) 50- and (right) 500-hPa geopotential height forecasts initialized during the DJF 2015–2018 period in the (top) Northern Hemisphere extratropics, (middle) tropics, and (bottom) Southern Hemisphere extratropics of individual ensemble members (solid gray lines) and their mean (solid black line) as well as the MSSSs of the ensemble mean with varying ensemble sizes (Ne = 2, 10, and 51; solid colored lines). The corresponding theoretical MSSSs of the ensemble-mean forecast calculated from Eq. (4) with varying ensemble sizes are shown as dashed colored lines