variable gravity

[WChen-NOAA]

Commit Queue Requirements:

• This PR addresses a relevant WM issue (if not, create an issue).
• All subcomponent pull requests (if any) have been reviewed by their code managers.
• Run the full Intel+GNU RT suite (compared to current baselines), preferably on Ursa (Derecho or Hercules are acceptable alternatives). Exceptions: documentation-only PRs, CI-only PRs, etc.
  • Commit log file w/full results from RT suite run (if applicable).
  • Commit 'test_changes.list' (unless file is empty).
• Fill out all sections of this template.

---

Description:

Initial NOAA-GFDL/GFDL_atmos_cubed_sphere#394
The model uses the shallow atmosphere approximation with constant gravity.
This is problematic for a space weather model (WAM) where Ztop/r0 )~10%
The method to resolve this issue is to Implement a scaling factor wherever gravity is applied to account for variations with height:
g(r0/r)^2 while setting var_grav = .true. in the name list
The new gravity as grav_var(i,j,k)
if setting var_grav = .false.
The model use an array contains the gravity acceleration constant and the bit of the array follows the compile setting.
This change will affect the results of non-WAM tests. Previously, the gravity constant was using a mix of 32-bit and 64-bit precision. It has now been changed to 3-D array. it is 32-bit or 64-bit depending on if the 32-bit compilation flag is enabled.

Commit Message:

* UFSWM - Add option of using variable gravity in FV3 dyn-core
  * UFSATM - Add option of using variable gravity in FV3 dyn-core
    * atmos_cubed_sphere - Add option of using variable gravity

Priority:

• Critical Bugfix: Reason
• High: Reason
• Normal

Git Tracking

UFSWM:

• Closes variable gravity #2915

Sub component Pull Requests:

• FV3:Variable gravity in fv3/atmos_cubed_sphere NOAA-EMC/ufsatm#1018 (comment)
  • atmos_cubed_sphere:Variable gravity  NOAA-GFDL/GFDL_atmos_cubed_sphere#395 (comment)

UFSWM Blocking Dependencies:

• Blocked by #
• None

Documentation:

• Documentation update required.
  • Relevant updates are included with this PR.
  • A WM issue has been opened to track the need for a documentation update; a person responsible for submitting the update has been assigned to the issue (link issue).
• Documentation update NOT required.
  • Explanation: this enhancement works for upper levels in whole atmosphere model.

---

Changes

Regression Test Changes (Please commit test_changes.list):

• PR Adds New Tests/Baselines.
• PR Updates/Changes Baselines.
• No Baseline Changes.

Input data Changes:

• None.
• New input data.
• Updated input data.

Library Changes/Upgrades:

• Required
  • Library names w/versions:
  • Git Stack Issue (JCSDA/spack-stack#)
• No Updates

---

Testing Log:

• RDHPCS
  • Hera
  • Orion
  • Hercules
  • GaeaC6
  • Derecho
  • Ursa
• WCOSS2
  • Dogwood/Cactus
  • Acorn
• CI
• opnReqTest (complete task if unnecessary)

[gspetro-NOAA]

@WChen-NOAA Could you fill out the PR template fully with information on baseline changes, input data, and so on? If you are still working on this PR and don't have the full details yet, that's fine, but I would just want to update the PR status appropriately in our tracker.

[WChen-NOAA]

@gspetro-NOAA Hi, Thank you for the suggestions. But this change has no baseline change and input data. Currently it works for upper atmosphere with whole atmosphere model (WAM). If for UFS-WM, the option needs to be set as false. And I will check the information again and fill out what I could do.

[gspetro-NOAA]

@WChen-NOAA When you have a chance, please finish filling out the PR template, especially the "commit message" section. This PR will probably be on hold until after the shutdown because reviewers for atmos_cubed_sphere likely cannot review until then, but once we can get the subcomponent PRs reviewed and the PR template completed, this PR will be ready to schedule.

[gspetro-NOAA]

@WChen-NOAA Just checking in on this PR. I haven't seen any updates, so I'm checking in to see if you have any questions/concerns.

[WChen-NOAA]

@gspetro-NOAA This PR needs to wait for the GFDL response.

[gspetro-NOAA]

@gspetro-NOAA This PR needs to wait for the GFDL response.

Thanks for the update!

[gspetro-NOAA]

@WChen-NOAA Have you had a chance to hear back from GFDL?

[WChen-NOAA]

Got suggestions for some changes in the code and I am working on that. @gspetro-NOAA

[gspetro-NOAA]

@WChen-NOAA Just checking in since I saw some code updates. Do you have more work to do on this PR, or are you still waiting on/working on feedback from your colleagues?

[WChen-NOAA]

@WChen-NOAA Just checking in since I saw some code updates. Do you have more work to do on this PR, or are you still waiting on/working on feedback from your colleagues?

@gspetro-NOAA Working on a issue of restart and diag

[gspetro-NOAA]

@WChen-NOAA How are things coming along? Looks like there's been progress, so I wanted to check in.

[WChen-NOAA]

@WChen-NOAA How are things coming along? Looks like there's been progress, so I wanted to check in.

@gspetro-NOAA Yes, you're right. If the regression tests has no problem, I will ask GFDL and see if it could go to next step.

[gspetro-NOAA]

@WChen-NOAA How are things coming along? Looks like there's been progress, so I wanted to check in.

@gspetro-NOAA Yes, you're right. If the regression tests has no problem, I will ask GFDL and see if it could go to next step.

How did the tests perform? I saw you ran a couple of tests on Ursa/Hera but haven't seen results from the full RT suite.

[WChen-NOAA]

@WChen-NOAA How are things coming along? Looks like there's been progress, so I wanted to check in.

@gspetro-NOAA Yes, you're right. If the regression tests has no problem, I will ask GFDL and see if it could go to next step.

How did the tests perform? I saw you ran a couple of tests on Ursa/Hera but haven't seen results from the full RT suite.

@gspetro-NOAA That is I found another issue, reported and I am working on it.

[gspetro-NOAA]

@WChen-NOAA Is this PR ready for testing, or are you still working on it?

[WChen-NOAA]

@gspetro-NOAA Still working on an issue.

[gspetro-NOAA]

@WChen-NOAA I see you've uploaded the logs, thanks! Is there more work you need to do, or can this PR start moving through the approval & commit process?

[WChen-NOAA]

@WChen-NOAA I see you've uploaded the logs, thanks! Is there more work you need to do, or can this PR start moving through the approval & commit process?

I think it is okay for approval & commit process. @XiaqiongZhou-NOAA
@gspetro-NOAA And the test_change.list is also uploaded. Some tests needs new baseline.

[DeniseWorthen]

Is this feature expected to change results for non WAM tests? I see a lot of changed tests.

[XiaqiongZhou-NOAA]

Is this feature expected to change results for non WAM tests? I see a lot of changed tests.

This change will affect the results of non-WAM tests. Previously, the gravity constant was using a mix of 32-bit and 64-bit precision. It has now been changed to 3-D array. it is 32-bit or 64-bit depending on if the 32-bit compilation flag is enabled.
@WChen-NOAA Wen, please correct me if I am wrong.

[DeniseWorthen]

Thanks for the explanation.

[WChen-NOAA]

@XiaqiongZhou-NOAA Thank you for answer the question.
@DeniseWorthen I will adding more description to the PR.