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Segmentation Error 174 running Obsgrid

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New member
Hi :
I was able to successfully compile obsgrid with intel 17. Upon execution of program, it gets as far as the opening the name list, observation files and listing the number of observations successfully integrated before it crashes. I really don't know what is going on. Some of the errors I get (with the 174 segsegv segmentation fault) refer to and libpthread-2.12.s.
Please if anyone can give any tips, I'd be most grateful....
I am also having this issue and am actively looking for a solution; any advice would be greatly appreciated!

Thank you,

Elliot Tardif
Can you please attach the namelist.oa file you're using, along with a log file, showing the error(s)?

If you are still experiencing the error, feel free to attach your files, as well. If you were able to get past it, would you mind letting us know the solution that worked for you? Thanks!
Good morning, please see the attached .zip file for the namelist.oa, obsgrid.out, and a datafile I am using that was produced by the get_rda_data.exe program. Please let me know if you'd like anything else. Thank you!

-Elliot Tardif


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Good morning all, I have found a solution to my problem. I updated to the latest version of OBSGRID (w/FASDAS), making no other changes to my input files, scripts or methodology. That update solved my problem.

For anyone else who is having this problem and does not believe it to be the version of OBSGRID you are using, it is important to remember to combine your surface/upper air obs files into one file, break 6-hour files into 3-hour files using util/get_rda_data.exe, then run OBSGRID using those 3-hour files. See the following excerpt from the WRF users guide (chapter 7):

NCEP operational global surface and upper-air observation subsets, as archived by the Data Support Section (DSS) at NCAR.

Upper-air data in NMC ON29 format (from early 1970s to early 2000)
Surface data in NMC ON29 format (from early 1970s to early 2000)
Upper-air data in NCEP BUFR format (from 1999 to present)
Surface data in NCEP BUFR format (from 1999 to present)
The newer data (ds351.0 and ds461.0) is also available in the little_r format. From outside NCAR, this data can be download from the web, while it is available on the NCAR /glade system for NCAR supercomputer users. This data is sorted into 6-hourly windows, which are typically too large for use in OBSGRID. To reorder this into 3-hourly windows:

· Get the little_r 6-hourly data

o Non-NCAR super-computer users. Get the data directly from the above web sites. Combine (by using the Unix ‘cat’ command) all the surface and upper-air data into one large file called rda_obs.

o NCAR super-computer users. Use the script util/get_rda_data.csh, to get the data and create the file rda_obs. You will need to edit this script to supply the date range that you are interested in.

· Compile the Fortran program util/get_rda_data.f. Place rda_obs file the in the top OBSGRID directory. Run the util/get_rda_data.exe executable. This executable will use the date range from namelist.oa, and create 3-hourly OBS:<date> files which are ready to use in OBSGRID.
Thank you so much for updating this post with your solution. This will hopefully help other users in the future. I'm glad you were able to get past the problem.