Consecutive dry days
Meteorological drought can in its simplest form be described by a lack of precipitation. First, a wet day threshold is set, which can be either a limit related to measurement accuracy, or more directly a process related to an amount that would break the drought. The diagnostic calculates the longest period of consecutive dry days, which is an indicator of the worst drought in the time series. Further, the diagnostic calculates the frequency of dry periods longer than a user defined number of days.
Available recipes and diagnostics
Recipes are stored in recipes/
Diagnostics are stored in diag_scripts/droughtindex/
diag_cdd.py: calculates the longest period of consecutive dry days, and the frequency of dry day periods longer than a user defined length
User settings in recipe
Required settings (script)
plim: limit for a day to be considered dry [mm/day]
frlim: the shortest number of consecutive dry days for entering statistic on frequency of dry periods.
Optional settings (script)
cmap: the name of a colormap. cmocean colormaps are also supported.
other keyword arguments to
esmvaltool.diag_scripts.shared.plot.global_pcolormesh()can also be supplied.
pr (atmos, daily mean, time latitude longitude)