[wrfems] temperatures crashing during night over water

[Kurt Mayer]

Bob sent out an email about this back in May... don't know if any action has
taken place since then.

I appreciate the users who brought this problem to my attention.

There appears to be a bug in the latest version of the WRF EMS (the WRF
itself actually)
in that using the default setting for SST_SKIN (ON) in run_physics.conf will
result in excessive
decreases in the skin temperature over water.

Change SST_SKIN = 0 (OFF) in your wrfems/conf/ems_run/run_physic
s.conf(.nmm)
and wrfems/runs/<domain>/conf/ems_run/run_physics.conf files - ASAP

A test simulation over the Gulf of Mexico showed water temperatures
decreasing from 80F (28C)
to less than 50F (10C) within a few hours after nightfall.  Setting
SST_SKIN= 0 corrected this
problem.


Bob


On Thu, Oct 27, 2011 at 12:05 PM, Bryan Mroczka <Bryan.Mroczka at noaa.gov>wrote:

>  I have been playing around with the EMS3.2beta release and have had some
> issues with my overnight 2meter temperatures over water/ocean. As soon as
> the model thinks the sun has set, it begins a rapid downward trend in the
> temps over the water. This eventually leads in a short time to some very
> unrealistic values. The issue seems to be related to the SST_SKIN variable.
> The default in the run_physics.conf file states that this should be set to
> 1. However, when I reset this variable to 0, the issue of low level temps
> over water goes away. I have tried several different short/long radiation
> options, always with basically the same result.
>
> Can anyone think of why this may be occurring with the SST_SKIN=1 variable
> set. I have attached my run_physics.conf file in hopes that someone might
> see a conflict in my configuration.
>
> Thanks
> Bryan
> WFO Tallahassee, FL
> --
> *Bryan Mroczka*
> bryan.mroczka at noaa.gov
> Meteorologist
> National Weather Service - Tallahassee, FL
>
> _______________________________________________
> wrfems mailing list
> wrfems at comet.ucar.edu
>
>
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