Update Orographic Gravity Drag scheme option 1

[Songyou184]

TYPE: enhancement

KEYWORDS: orographic drag

SOURCE: Songyou Hong (NCAR)

DESCRIPTION OF CHANGES:
YSU GWDO was revised following the study of Hong et al. (2025, WAF), now is called as Korean Integrated Model (KIM) GWDO. KIM GWDO requires additional maximum orography file, "ELVMAX" in WPS. Non-hydrostatic effect of Xu et al. (2024, JAS) was also added (gwd_if_nonhyd=.true., default). Factor for the effective grid spacing was added (gwd_dx_factor=2.0, default).

LIST OF MODIFIED FILES:
m Registry/Registry.EM_COMMON
m arch/Externals.cfg
m dyn_em/module_first_rk_step_part1.F
m phys/module_bl_gwdo.F
m phys/module_pbl_driver.F

TESTS CONDUCTED:

1. Tested in MPAS.
2. The Jenkins tests are all passing.

RELEASE NOTE: Include a stand-alone message suitable for the inclusion in the minor and annual releases. A publication citation is appropriate.

[weiwangncar]

@Songyou184 @dudhia It doesn't seem that the GWDO and ShinHong PBL code are separated. Both PRs 2285 and 2286 contain changes for both options.

[Songyou184]

4D var part : module_first_rk_step_part1_ad.F, module_pbl_driver_ad.F are revised.

[weiwangncar]

The regression test results:

Test Type              | Expected  | Received |  Failed
= = = = = = = = = = = = = = = = = = = = = = = =  = = = =
Number of Tests        : 23           24
Number of Builds       : 60           57
Number of Simulations  : 158           150        0
Number of Comparisons  : 95           86        0

Failed Simulations are: 
None
Which comparisons are not bit-for-bit: 
None

[dudhia]

May need updating. Conflicts cannot be resolved via github.

[dudhia]

Updated code.

[weiwangncar]

@dudhia @Songyou184 Can you update the PR message?

[dudhia]

@weiwangncar Check into this failure too.

[weiwangncar]

@dudhia @Songyou184 In this case, the compilation failed mainly due to code issues. The error is

module_bl_gwdo.f90:219:26:
  219 |                     ,omax=elvmax_hv                           &
      |                          1
Error: Keyword argument 'omax' at (1) is not in the procedure

It appears in making changes to bl_gwdo.F90 in MMM-physics, Songyou made two changes: the first PR made some changes, and the second one reversed part or all of the first changes, which made omax not being included in the bl_gwdo_run call.

[Songyou184]

MMM-physics includes the original bl-gwdo.F. For complete physics_mmm, bl-gwdo.F in songyou184 physics-mmm branch MMM2026 GWDO should be incorporated. Somehow it was merged from the MMM2026 SFCLAY or SHPBL which uses the original bl-gwdo.F 2026년 3월 7일 (토) 오전 6:43, weiwangncar ***@***.***>님이 작성:

…

*weiwangncar* left a comment (wrf-model/WRF#2285) <#2285 (comment)> @dudhia <https://github.com/dudhia> @Songyou184 <https://github.com/Songyou184> In this case, the compilation failed mainly due to code issues. The error is module_bl_gwdo.f90:219:26: 219 | ,omax=elvmax_hv & | 1 Error: Keyword argument 'omax' at (1) is not in the procedure It appears in making changes to bl_gwdo.F90 in MMM-physics, Songyou made two changes: the first PR made some changes, and the second one reversed part or all of the first changes, which made omax not being included in the bl_gwdo_run call. — Reply to this email directly, view it on GitHub <#2285 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AVR3U6WLJTC22A65HFNLPWD4PQRRRAVCNFSM6AAAAACVX77FSSVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHM2DAMJWGU2DQMBWHE> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[Songyou184]

For Shinhong pbl PR, the new bl_gwdo.F was restored as the original one.

…

On Sat, Mar 7, 2026, 06:43 weiwangncar ***@***.***> wrote: *weiwangncar* left a comment (wrf-model/WRF#2285) <#2285 (comment)> @dudhia <https://github.com/dudhia> @Songyou184 <https://github.com/Songyou184> In this case, the compilation failed mainly due to code issues. The error is module_bl_gwdo.f90:219:26: 219 | ,omax=elvmax_hv & | 1 Error: Keyword argument 'omax' at (1) is not in the procedure It appears in making changes to bl_gwdo.F90 in MMM-physics, Songyou made two changes: the first PR made some changes, and the second one reversed part or all of the first changes, which made omax not being included in the bl_gwdo_run call. — Reply to this email directly, view it on GitHub <#2285 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AVR3U6WLJTC22A65HFNLPWD4PQRRRAVCNFSM6AAAAACVX77FSSVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHM2DAMJWGU2DQMBWHE> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[weiwangncar]

@Songyou184 @dudhia It needs to be committed to MMM-physics as current PR points to that repository.

[dudhia]

I will also mention again that develop points to an old tag of MMM-physics as we haven't been using submodules for it up till now. Someone needs to fix that.

[islas]

develop points to an old tag of MMM-physics as we haven't been using submodules for it up till now. Someone needs to fix that.

I don't follow. What is the problem with develop, should we be pointing to a newer tag? When PR #2282 went in, it put the submodule to point to the exact same tag that manage_externals was using

[dudhia]

MMM-physics was updated with some new modules in recent PRs that we need for V4.8.

[islas]

These PRs (#2284 #2285 #2286) update the submodule to point the new tag that incorporates those MMM-physics changes. Updating the submodule in develop independently outside of these PRs should not be done.