The algorithm tracks geopotential height minima or relative vorticity maxima to identify cyclones as sources of extreme weather.

First phase: ERA5 reanalysis data from 1979-2019

Second phase: reanalysis data from 1950-1978 (currently in development)

For the serial clustering of extremes total precipitation and wind gust data from ERA5 (global), COSMO-REA6 (Europe) and possibly, the HYRAS (Germany) dataset are used.