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Valid values for dtlimit in the datm_in file

sur23beeb

ST
New Member
Hi all,
I am doing an ocean+ice simulation forced by JRA55 atmospheric fields. The nominal ocean grid resolution is 0.1 degree. Here are some relevant details:

resolution: TL319_t13
compset: 2000_DATM%JRA_SLND_CICE_POP2_DROF%JRA_SGLC_SWAV
cesmtag: cesm2.1.4-rc.08

I have a question regarding the parameter dtlimit in the file datm_in, located in the run/ folder. Here are the values for the 10 different data-atmospheric streams:

Code:
dtlimit = 1.5, 1.5, 1.5, 1.5, 1.5, 1.5, 1.5, 1.5, 1.5, 1.5

While compiling the same configuration on a different machine (Xsede), here are the corresponding values from the same file:

Code:
dtlimit = 1.5, 1.5, 1.5, 1.5, 1.5, 1.5, 1.5, 1.5, 1.e30, 1.5

For some reason, the second-last value is different. I looked up the description for this parameter (link) and the value 1.e30 apparently is used to turn off "trapping" missing data or errors in the data streams. Is there a reason the parameter is taking on different values on the two machines? I guess I could just change it manually in datm_in if I wanted to, assuming other parameter settings do not hinge on this value.

Thanks.
 

sur23beeb

ST
New Member
Sorry for bumping this post but does anybody know how sensitive are simulations to values of dtlimit in the datm_in file?
 
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