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Precipitation units

I would like to compare future precipitation (pr) with the historical record, however the unit for precipitation is different than what I've seen before (kg m^-2 s^-1). Can this be directly translated to the standard unit of measurement for precipitation (mm^3 m^-2)? I thought that the value would be monthly totals, but it seems to be the average per second. I'm using the data to create maps in NCL, so if there is an NCL function that can convert the values, that would be useful, but I have yet to find one. If not, I can do it by hand as long as it is a direct conversion.

Normally, I would work with PRECC and PRECL, but I could not find them in the newer data sets. This is the site where I have been downloading the data. https://www.earthsystemgrid.org/search?Project=CMIP5&Experiment=rcp85&Ensemble=r6i1p1

Brandi
 

strandwg

Moderator
Staff member
The CMIP5 standard for precipitation is kg m-2 s-1, i.e., a mass flux per unit area per unit time.The standard CAM units for precipitation are m s-1; to convert between simply divide 'pr' by 1000 kg m-3, or, multiply PRECC/PRECL by 1000 kg m-3. 
 
Hello I would also like to convert the total precipitation into (kg m^-2 s^-1) and if i understand correctly then all you do ia divide by a 1000 to convert m/s into kg/m^2/s?
 
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