Feature/swdnclrskyflx diag

[dustinswales]

Commit Queue Requirements:

• Fill out all sections of this template.
• All sub component pull requests have been reviewed by their code managers.
• Run the full Intel+GNU RT suite (compared to current baselines) on either Hera/Derecho/Hercules
• Commit 'test_changes.list' from previous step

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Description:

This PR adds a new diagnostic, instantaneous downward shortwave flux at the surface assuming clear-sky conditions.
This is needed for RRFSv1.

Commit Message:

N/A

Priority:

• High: Time-sensitive project. Needed for RRFSv1.

Git Tracking

UFSWM:

N/A

Sub component Pull Requests:

* FV3: NOAA-EMC/fv3atm#824
*ccpp-physics: ufs-community/ccpp-physics#197

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Changes

Regression Test Changes (Please commit test_changes.list):

No changes to baselines.

Input data Changes:

N/A

Library Changes/Upgrades:

N/A

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Testing Log:

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

[dustinswales]

Closing this one. Targeting RRFSv1 branch instead.