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UCM configuration problem using NUDAPT (Houston)

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Dear WRF community,

I'm writing for a problem when using NUDAPT in UCM/WRF. My purpose is to run a test for Houston area using available datasets.

(1) The files NUDAPT44_1KM, urbfrac_nlcd2011 within Urban Tar File are downloaded from, and placed to GEOG/WPS_GEOG_HIGH_RES/.

(2) in namelist.input, changed the options:
& physics
sf_surface_physics=2 (noah model)
sf_urban_physics = 0, 1, (UCM) 2, (BEP) 3 (BEM)
num_land_cat = 33,

Question 1: WPS geogrid.exe, ungrid.exe and metgrid.exe are successfully executed. -----URB_PARAM, FRC_URB2D are generated in geo_em.d0*.nc. WRF ./real.exe also runs well. However, when ./wrf.exe, it fails with errors as follows (with num_land_cat = 21):

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

Backtrace for this error:
#0 0x7F31CF891697
#1 0x7F31CF891CDE
#2 0x7F31CEB6C27F
#3 0x2A59ADD in __module_sf_sfclayrev_MOD_psim_stable
#4 0x2A5E12C in __module_sf_sfclayrev_MOD_sfclayrev1d
#5 0x2A6300D in __module_sf_sfclayrev_MOD_sfclayrev
#6 0x210B172 in __module_surface_driver_MOD_surface_driver
#7 0x185E089 in __module_first_rk_step_part1_MOD_first_rk_step_part1
#8 0x12228CF in solve_em_
#9 0x10FBC65 in solve_interface_
#10 0x474D80 in __module_integrate_MOD_integrate
#11 0x406FE3 in __module_wrf_top_MOD_wrf_run
Segmentation fault (core dumped)

Question 2: I tried to change num_land_cat = 21 to num_land_cat=33 in namelist.input. When executing ./real.exe, there is a mismatch error. My question is how to change num_land_cat to 33 in geogrid?

----------------- ERROR -------------------
namelist : NUM_LAND_CAT = 33
input files : NUM_LAND_CAT = 21 (from geogrid selections).
d01 2015-08-15_12:00:00 ---- ERROR: Mismatch between namelist and wrf input files for dimension NUM_LAND_CAT
NOTE: 1 namelist vs input data inconsistencies found.
-------------- FATAL CALLED ---------------
NOTE: Please check and reset these options
-------------- FATAL CALLED ---------------
NOTE: Please check and reset these options

Any indications? Thanks very much


  • namelist.wps.txt
    1.3 KB · Views: 81
  • namelist.input.txt
    4.3 KB · Views: 80
This is a bug in the WRF model prior to version 4.1

Please download the newest version (WRFV4.1) and rerun this case.

Let us know if you still have the problem.

For the NUM_LAND_CAT, its value in namelist must be the dame as that in met-em file. Please find the correct value by
ncdump -h met-em and NUM_LAND_CAT is a global attribute.
Thanks very much. I will try V4.1.

BTW, would you look at this: Another topic on compilation problem.