Bugfix: Use correct physics constant for theta in AMDAR PBLH METplus use case

[jason-english]

Describe the Problem

Correct a minor error in the potential temperature (theta) computation. Theta should be calculated using reference pressure (100000 Pa), not SLP (101325 Pa).

Expected Behavior

The primary purpose of this change is to have physics accuracy. This should have a small, but real, impact on the PBLH computation. The impact will be small because the correction will shift the entire theta profile, therefore having a negligible impact on the delta theta computation.

Environment

I may try this on Ursa; I previously used Jet before it was shut down.

To Reproduce

See METplus use cases: Planetary Boundary Layer (PBL); the error is in the python embedding script

Relevant Deadlines

April 30, 2026

Funding Source

NONE

Assignee

Jason English
Daniel Adriaansen

Define Related Issue(s)

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