Compound event
Added by Michael Akin about 1 year ago
Hello,
I would appreciate it if someone could assist me with a CDO code to calculate the simultaneous occurrence of an event. Using maximum and minimum daily temperature, I want to compute a compound heatwave event of "at least three consecutive days with simultaneous occurrence of Tmax ⩾ 90th percentile and Tmin ⩾ 90th percentile". Thank you.
Replies (4)
RE: Compound event - Added by Karin Meier-Fleischer about 1 year ago
Hi Michael,
I'm not quite sure but I would do something like
cdo -chname,ta,tamin -timselmin,3 infile.nc tmin3.nc cdo -chname,ta,tamax -timselmax,3 infile.nc tmax3.nc cdo -chname,ta,ta90 -timselpctl,90,3 infile.nc tmin3.nc tmax3.nc tpctl90.nc cdo -O -merge tmin3.nc tmax3.nc tpctl90.nc tmp.nc cdo -expr,'heat=((tamin >= ta90) && (tamax >=ta90))?1:0' tmp.nc outfile.nc
RE: Compound event - Added by Michael Akin about 1 year ago
Thank you so much, Karin.
This may be a silly question. What if I want the 90th percentile of the Tmax and Tmin based on a "5-day window (5-day moving window centered on each calendar day)"? How do I include that?
RE: Compound event - Added by Karin Meier-Fleischer about 1 year ago
Have a look at
https://code.mpimet.mpg.de/projects/cdo/embedded/cdo.pdf#subsection.2.8.13
https://code.mpimet.mpg.de/projects/cdo/embedded/cdo.pdf#subsection.2.8.14
In the commands from above change the nset=3 to nset=5, e.g.
-timselmin,5 -timselmax,5 -timselpctl,90,5