[Wrf-users] WRF running problem---rrtm: TBOUND exceeds table limit: reset 346.143

[Eric Altshuler]

Dear Yan Bao,

These messages indicate that the skin temperature at some grid point(s) exceeds 340 K, which is physically possible in hot desert regions in summer (e.g. Sahara and Arabian deserts). If part of your model domain covers one of these deserts and you are running WRF in the summer season, it is normal for these messages to occur in the course of a successful run. They do not necessarily indicate that the model is becoming unstable. If the reported values frequently exceed 345 K, you may want to increase the frequency of radiation calls (set radt to a smaller value).

If you see these messages during a run in which skin temperature above 340 K is implausible (e.g. winter season, or domain does not cover any desert regions) then something is going wrong. In my case, WRF was blowing up for a reason completely unrelated to the TBOUND messages (I was running a nest that extended poleward of 45 degrees where polar filtering is applied in the global model, and in my experience this will generally cause WRF to blow up, so it must be avoided).

Best regards,

Eric L. Altshuler
Assistant Research Scientist
Center for Ocean-Land-Atmosphere Studies
4041 Powder Mill Road, Suite 302
Calverton, MD 20705-3106
USA

E-mail: ela at cola.iges.org
Phone: (301) 902-1257
Fax: (301) 595-9793

----- Original Message -----
From: ybao at berkeley.edu
To: ela at cola.iges.org
Sent: Tuesday, July 7, 2009 6:00:11 PM GMT -05:00 US/Canada Eastern
Subject: WRF running problem---rrtm: TBOUND exceeds table limit: reset     346.143

Hi,Eric L.Al tshuler
     I saw your poster in
http://mailman.ucar.edu/pipermail/wrf-users/2008/000910.html . Now I
met the same problem with you when running WRF regional model. Could
you tell me  if you have fixed the problem and how you fix it?
     Thanks very much for that.

     Yan Bao