Obs Nudging implementation

[StephM]

Hi
I have been exploring the nudging options from cyclones and so far I have been successful in nudging ERA5 data in the coarse domain ( I am using 3 nested domains)

I want to see if I can improve even more the cyclone trajectory using cyclone track data. For this I created the OBS_DOMAIN file, but my runs are not changed at all ( I tried asking the obs nudging to be done in D01 and D03 and non are changed, even created very high winds compared to the control and no changes are made). Reading the manual, it seems I would need to run obsgrid.exe to produce metoa files but my obsgrid.exe is failing too and not so sure what to do now

I attach the namelist.input, rsl.error and OBS_DOMAIN files: For this ones, I made the run without obsgrid.exe. Results do not changed compared to only grid_nudging
I attach the namelist.oa file that I am using to try to run obsgrid.exe (this is using the previous OBS_DOMAIN and met_em files from WPS) and the errors from running obsgrid as obsgrid.out

 

[Ming Chen]

Hi,
Please take a look at the document here, which describes in detail about the OBSGRID program.
However, note that this program requires special treatment of observations mainly over the land. I don't think it is feasible to use it for TC track study.

 

[StephM]

Thanks for your response

I looked at the link, and run some test, as you say it is not feasible for TC tracks.

 

[Ming Chen]

Yes that is understandable. OBSGRID is designed to assimilate high-density observations over land.