NCEP/HPC - European Centre for Medium-Range Weather Forecasts

Fig. a
Fig. b
Potential errors with frequency
distributions derived from a single
ensemble system
Lower ensemble resolution compared to
global runs can lead to increased regime
dependent bias and less skill (fig. a)
Ensembles and respective global runs are
often too closely correlated (figs. b, c)
* Multi-center ensemble systems may offer
a more representative forecast distribution
Fig. c