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error in urban net longwave

xjliu@uw_edu

New Member
Hi,  I am trying to do a deep time experiment. I have changed the land/sea geometry, domain files, mapping files, surface data files and atmosphere boundary files following the instruction of the paleoresources for CESM1.2. The model ran but stopped after timestep 1, and gave error message "urban net longwave radiation error: no convergence". I thought it was because I didn't change the aerosol accordingly. I then used the zonal mean aerosol (over land and ocean respectively), but still received the same error message. 
I googled the forum. One post suggested that "this error typically actually indicates an error coming from the atmosphere with some unrealistic downwelling longwave radiation.  It crashes in the urban model because that is the first part of CLM that uses the atmospheric longwave. So usually the fact it crashes in the urban model doesn't reflect anything is wrong with the urban but bad values are passed to the urban model ". But I have no idea how to pinpoint where the problem with atmosphere is. 
Does anyone have any idea how to fix this? This is urgent. Thank you very much. 
 
 

9-Jean Li

New Member
Hi Xiaojun Liu!I had the same error message the other day, then I found the error disappear when I modified my inpute date by interpolating the missing value and assigning NAN to -1.8. Your analysis of the error inspired me, and I hope you can solve the problem at an early date.Sincerely.
 

xjliu@uw_edu

New Member
Hi, The error of mine is from the nan value in the land/ocean domain. All the problems related to the deep time simulation are solved. I would be happy to help if you run into any relevant question in the future. 
 
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