Summarising ensembles using a mean and a reasonable worst-case

by Steve Jewson (Weather and climate risk consultant)


For some applications of ensembles it may not be possible to process every ensemble member. One approach is to reduce the ensemble down to just the mean and a reasonable worst-case before processing. I describe a simple statistical methodology for creating the worst-case, and apply it to EURO-CORDEX rainfall projections and ECMWF medium range temperature forecasts.