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Cloud height information

Posted: May 4th, 2021, 3:56 am
by radyandre
Hi,
I'm a new Hysplit user. I would like to run some backward trajectories to retrace the origin of below-cloud (wet) deposited material. To do so, I would need to know the bottom cloud height at my starting location, to set the release altitude properly (e.g. not above the clouds). Is there a way to know this parameter, may be in the meteorology output file?

I already checked https://www.ready.noaa.gov/hysplitusersguide/S410.htm and it seems there isn't this possibility.

Re: Cloud height information

Posted: May 7th, 2021, 2:48 pm
by ariel.stein
It will depend on the meteorological dataset you want to use. Most of our datasets contain a precipitation field (e.g. 6 hour accumulated precipitation; TPP6 for GDAS) and a relative humidity field. For our deposition calculations using the dispersion model we use 80 % relative humidity as the threshold to find the bottom of the precipitation layer and once the relative humidity drops below 60% we use that as the top. To extract the data you can use a utility called profile.exe located in c:/hysplit/exec/. Also, you can run it through the GUI by clicking Meteorology/Display Data/Text Profile

Re: Cloud height information

Posted: May 25th, 2021, 10:57 am
by radyandre
Thank you, I will try for sure!