Search found 1361 matches

by Ming Chen
Thu Apr 08, 2021 11:42 pm
Forum: metgrid
Topic: The mandatory field TT was not found in any input data.(I found same question but not work for me.)
Replies: 6
Views: 24

Re: The mandatory field TT was not found in any input data.(I found same question but not work for me.)

Sam, I am suspicious that something is already wrong when you run ungrib. The gfs file may not be successfully ungribbed. Please download GFS data at the websites: https://rda.ucar.edu/datasets/ds084.1/ remember the keep the filename as is in the website and don't change it. Then you should use Vtab...
by Ming Chen
Thu Apr 08, 2021 3:42 pm
Forum: Miscellaneous WRF
Topic: Extracting Minimum Temperature
Replies: 5
Views: 33

Re: Extracting Minimum Temperature

This may be caused by possible bugs in older version of WRF. However, it is not our top priority to debug any issues in older version. Would you please update WRF to newer version such as WRFV4.2, then try again? Please check the file wrfxtrm and all variables defined for the output_diagnostics pack...
by Ming Chen
Wed Apr 07, 2021 4:00 am
Forum: metgrid
Topic: The mandatory field TT was not found in any input data.(I found same question but not work for me.)
Replies: 6
Views: 24

Re: The mandatory field TT was not found in any input data.(I found same question but not work for me.)

Would you please run the utility rd_intermediate.exe to check your intermediate file. The command is:
WPS/util/rd_intermediate.exe filename > log
Please send me the log file to take a look. Thanks.
by Ming Chen
Tue Apr 06, 2021 8:17 pm
Forum: WRF Code Modification
Topic: parallel netcdf-4 for WRF: Is there interest?
Replies: 2
Views: 12

Re: parallel netcdf-4 for WRF: Is there interest?

Ted,
Would you please put a PR in GitHub? Then we can talk about the issue and proceed. Thanks!
Ming
by Ming Chen
Tue Apr 06, 2021 6:27 pm
Forum: WRF Code Modification
Topic: parallel netcdf-4 for WRF: Is there interest?
Replies: 2
Views: 12

Re: parallel netcdf-4 for WRF: Is there interest?

Ted,
Thanks for the kind information. I will forward your message to our software engineer and he will get back to you.
I know that some researchers do need this capability, especially those who work in the field of climate study.
Ming
by Ming Chen
Mon Apr 05, 2021 9:41 pm
Forum: WRF Physics
Topic: LCZ Classes at WRF 4.2.2
Replies: 1
Views: 4

Re: LCZ Classes at WRF 4.2.2

LCZ will be included in WRRFV4.3, and this new version of WRF will be released soon ( April 2021, the exact date of release hasn't been decided yet). Do you mind waiting for the release of WRFV4.3? if you are in urgent need of this code, please let me know and I can send you a copy (not well tested ...
by Ming Chen
Mon Apr 05, 2021 9:39 pm
Forum: WRF Physics
Topic: Usage of the newly added SMS-3DTKE PBL
Replies: 9
Views: 442

Re: Usage of the newly added SMS-3DTKE PBL

The SMS-3DTKE scheme will treat the PBL process at coarse resolution (such as 25km) in a way more similar to traditional PBL scheme. When the grid interval becomes smaller, this scheme gradually transfer to LES mode. cumuls parameterization must be turned on for grid intervals larger than 10km, and ...
by Ming Chen
Mon Apr 05, 2021 9:33 pm
Forum: WRF Physics
Topic: WRF-LES(Real data) microphysics doesn't work
Replies: 4
Views: 129

Re: WRF-LES(Real data) microphysics doesn't work

For real-data case, 100m is way too coarse for the surface layer and lower PBL layer. Unreasonable model configuration may cause problem in model run and damage the simulation. Please refer to the literature for real-data LES simulation. Probably you can take a look at this paper: https://ui.adsabs....
by Ming Chen
Mon Apr 05, 2021 9:27 pm
Forum: ungrib
Topic: Downloaded GFS data unable to get executaed by ungrib.exe
Replies: 2
Views: 16

Re: Downloaded GFS data unable to get executaed by ungrib.exe

This is because you don't have the GFS data at 2021-03-26_09:00:00.00

Please take a look at your GRIB file, and make sure the GFS file at the above time does exist in your working directory.
by Ming Chen
Mon Apr 05, 2021 8:11 pm
Forum: metgrid
Topic: lowest levels in metgrid are below the surface
Replies: 5
Views: 29

Re: lowest levels in metgrid are below the surface

You can check wrfinput_d01, looking at all upper level data. But I won't expect anything wrong in REAL. This is because we have done many cases with levels below ground in met_em files. Would you please tell what is the error message in your rsl files when you run wrf.exe? Probably that can give us ...
by Ming Chen
Mon Apr 05, 2021 4:11 pm
Forum: metgrid
Topic: lowest levels in metgrid are below the surface
Replies: 5
Views: 29

Re: lowest levels in metgrid are below the surface

Peter, I looked at the website https://rda.ucar.edu/datasets/ds083.3/, which provides the FNL data you use to run the case. This FNL data has 26 mandatory (and other pressure) levels from 1000 millibars to 10 millibars. But in your namelist.input, you set p_top_requested = 100, num_metgrid_levels = ...
by Ming Chen
Mon Apr 05, 2021 4:02 pm
Forum: Miscellaneous WRF
Topic: Extracting Minimum Temperature
Replies: 5
Views: 33

Re: Extracting Minimum Temperature

Can you run with the options below (and keep all other options the same)
auxhist3_outname = "wrfxtrm_d<domain>_<date>"
Please let me know if you still cannot run the case.
by Ming Chen
Mon Apr 05, 2021 3:52 pm
Forum: Miscellaneous WRF
Topic: Icing forecast
Replies: 3
Views: 32

Re: Icing forecast

WRF doesn't directly output such information. I know some people derive this information based on WRF simulation. Please take a look at this paper, which may provide some helpful information:

https://journals.ametsoc.org/view/journ ... 0125_1.xml
by Ming Chen
Fri Apr 02, 2021 3:06 pm
Forum: metgrid
Topic: Error in ext_pkg_write_field
Replies: 3
Views: 50

Re: Error in ext_pkg_write_field

If you are running this case just for practice and try to get familiar with the model system, I would suggest you don't use the intermediate file downloaded from the website. You can always start from the right beginning, i.e., run geogrid, ungrib and metgrid. I suppose this is a better way to learn...
by Ming Chen
Thu Apr 01, 2021 10:48 pm
Forum: metgrid
Topic: lowest levels in metgrid are below the surface
Replies: 5
Views: 29

Re: lowest levels in metgrid are below the surface

Hi,
It is not unusual that some metgrid levels are blow the ground. Thy shouldn't cause problems because REAL program will handle this issue later.
What is the error message in your WRF run? Please send me your namelist.wps and namelist.input to take a look.
by Ming Chen
Mon Mar 29, 2021 8:27 pm
Forum: geogrid
Topic: Question about geographical data
Replies: 3
Views: 36

Re: Question about geographical data

Hi, The webpages you referred to are really old, --- I am sorry for the trouble caused by this. The default options have been changed in newer version of WRF/WPS (and also the corresponding data that can be used), which explain why the older files cannot be found. It is great that you can figure out...
by Ming Chen
Mon Mar 29, 2021 6:08 pm
Forum: metgrid
Topic: ERROR: Didn't recognize format version of data in FILE:2021-03-22_00.\nFound version 83886080 but expected either 3, 4,
Replies: 2
Views: 27

Re: ERROR: Didn't recognize format version of data in FILE:2021-03-22_00.\nFound version 83886080 but expected either 3,

Did you run ungrib to produce the intermediate file yourself? or you get these files from somewhere else?
What is the forcing data for this case ( the data you ungrib)?
by Ming Chen
Mon Mar 29, 2021 6:04 pm
Forum: metgrid
Topic: Error in ext_pkg_write_field
Replies: 3
Views: 50

Re: Error in ext_pkg_write_field

If metgrid.exe can successfully process data of 2010-07-14_00, it indicates that the code is fine. This is more likely a data issue. Can you look at the size of the files, and also check the content of the files by running rd_intermediate.exe?
by Ming Chen
Mon Mar 29, 2021 6:00 pm
Forum: New/Modified Static Data
Topic: SRTM data into Geogrid -
Replies: 11
Views: 1264

Re: SRTM data into Geogrid -

Many thanks for the kind information !
by Ming Chen
Mon Mar 29, 2021 5:54 pm
Forum: Special Running Options
Topic: SST variable in wrfout files
Replies: 2
Views: 27

Re: SST variable in wrfout files

Would you please confirm that you look at SST in wrfout and compare with SST in wrflowinp, and you find they are different? Can you clarify how you compare SSTs from the two files? It will be helpful if you can upload a figure to show the difference. thanks.
by Ming Chen
Mon Mar 29, 2021 5:51 pm
Forum: Special Running Options
Topic: Adaptive time_step in very stable conditions
Replies: 3
Views: 27

Re: Adaptive time_step in very stable conditions

Also, if the terrain is very steep, please increase the value of epssm probably from 0.1 to 0.5, which will increase the model stability.
by Ming Chen
Mon Mar 29, 2021 5:50 pm
Forum: Special Running Options
Topic: Adaptive time_step in very stable conditions
Replies: 3
Views: 27

Re: Adaptive time_step in very stable conditions

HI, I think that time-step =6, 2, 1 could be too small. I would suggest that you try the default options: starting_time_step(max_dom) = -1,-1, -1 which indicates that the model will use 6 * dx as the start_time_step. It will adjust the time step later based on target_cfl and max_step_increase_pct Pl...
by Ming Chen
Mon Mar 29, 2021 5:35 pm
Forum: ungrib
Topic: ungrib.exe > link_grib.csh ...> what data file ? where is it?
Replies: 1
Views: 40

Re: ungrib.exe > link_grib.csh ...> what data file ? where is it?

link_grib.csh will link all WRF forcing data to your WPS directory and rename them as GRIBFILE.AAA, GRIBFIL.AAB, ...
The forcing data could be any analysis/reanalysis/forecast products like GFS, ERA-I, etc.
by Ming Chen
Mon Mar 29, 2021 5:30 pm
Forum: ungrib
Topic: Creating Vtable
Replies: 1
Views: 53

Re: Creating Vtable

Please take a look at the document below, which provides detailed instruction how to create Vtable:

https://www2.mmm.ucar.edu/wrf/users/doc ... _Editing_1

Hope this is helpful.
by Ming Chen
Mon Mar 29, 2021 5:27 pm
Forum: WRF Physics
Topic: wrf ocean physics
Replies: 5
Views: 65

Re: wrf ocean physics

Please take a look at the code phys/module_sf_oml.F. You may also need to refer to the paper for more information
Pollard, R. T., P. B. Rhines, and R. O. R. Y. Thompson, 1973: The deepening of the wind–mixed layer. Geophys. Fluid. Dyn., 3, 381–404. doi:10.1080/03091927208236105

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