Cold wave duration index (cwdi)

TechnicalInfo: cdo -eca_cwdi TN.nc -ydrunmean,5 TNref.nc out.nc Other: Duration of cold wave: Let TNt be the daily maximum temperature on day t and TN’t be the climatological average of a running 5 day mean (1981-2010), then cwdi is the longest period of consecutive days (≥ 6 days) in one year, where TNt < TN’t -5°C.