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WRF UCM run_time error ( Segmentation fault )

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Dear WRF community,

I am trying to run WRF with UCM urban option. An error prompt out after executing ./wrf.exe. The log file as well as namelist.input, namelist.wps are attached.

Program received signal SIGSEGV: Segmentation fault - invalid memory reference.

Any indication is appreciated. Thanks.



  • namelist.input
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  • namelist.wps
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  • namelist.output.txt
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  • log.wrf.UCM.txt
    1.5 KB · Views: 51
I'm not sure of the exact cause of the segmentation fault, but I notice several things immediately that could cause the problem:
1) We recommend setting the time_step to no more than 6xDX. Your DX = 1000, which means you shouldn't have a time_step larger than 6.
2) Your d01 is 200x200 and you're only using a single processor. You likely need a few more processors to run a domain of this size.
3) Your d01 has a resolution of 1km. What is the resolution of the input data you are using? It is recommended to not have too much of a gap in resolution between the input data and the resolution of d01 (probably nothing more than about a 7:1 ratio).
4) You are running 2 domains, but d01 and d02 have the exact same resolution, and with a 1:1 ratio. If you are going to have a nested domain, it should be a higher resolution, and should be embedded in d01.

I would recommend reviewing this 'best practice' web pages that can help you to create a reasonable domain set-up:

I would also recommend taking a look at this FAQ that will help you to choose an ideal amount of processors to use: