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Calculation of Cloud Liquid water path from WRF out file using ncl


New member
Hi all

I am tring to get CLWP from WRF out file.

I tried prcwater_dp as follows:

q1 = f1->QCLOUD[:,:,:,:]; kg/kg

dp_a = wrf_user_getvar(f1,"p",-1)
dp1 = dp_a[:,:,:,:]; Pa

q1!0 = "time"
q1!1 = "lev"
q1!2 = "lat"
q1!3 = "lon"

dp1!0 = "time"
dp1!1 = "lev"
dp1!2 = "lat"
dp1!3 = "lon"

lwp_a = prcwater_dp (q1(time|:,lat|:,lon|:,lev|: ), dp1(time|:,lat|:,lon|:,lev|: ) ; kg/m2

Here I am getting values like
27.09562 45.50217 61.3766 68.90879 67.90661 66.62698 64.72494 67.85168 64.0595 62.04931 55.23169 42.21736 23.00407... in kg/m2

I also tried wrf_user_getvar(f1,"pw",-1).
Here I am getting values like

5.871577 6.066606 6.3876 6.375202 6.273459 5.973719 6.050189 6.115168 6.225941 6.275452 6.347611 6.305155 6.381238 ... in kg/m2

But the realistic values are very small compared to what I am getting, based on previous literature:
To what extents do urbanization and air pollution affect fog? states values ~0-160 g/m2
ACP - Radiative forcing estimates of sulfate aerosol in coupled climate-chemistry models with emphasis on the role of the temporal variability staes values ~0-240 g/m2 and many examples are there. They all show clwp in g/m2 which is about 0-300 g/m2 range.

So why I am getting very high values. Are the units in kg/m2 correct for the functions 'pw' and prcwater_dp?Or, am I doing something wrong!

Looking forward to any kind of help.

Thank you
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