CAM6 Development - Coupled simulations specific to AMWG


Subgrid Orographic Drag Development

Non-isotropic orographic and form drag (Beljaars) schemes are being developped and tested (from: Julio Bacmeister)
The goal is to replace the existing turbulent mountain stress (TMS) scheme, because TMS produces low wind speeds and poor flow around orography.

The momentum diffusion may need to be reformulated in CLUBB, after assessment in dry PNL conditions, in order to accommodate these changes.
Due to the existing dependence of vertically propagating gravity waves and the frequency of Sudden Stratospheric Warmings (SSWs) in WACCM, frequent testing and coordination with the WACCM group will be needed.

ID Case Description Diagnostics Details/Comments


Control run with CAM5.5.
CLUBB cK10=0.3,
TMS on,
original isotropic mountain wave scheme:

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CLUBB cK10=0.6,
TMS turned off replaced with Beljaars scheme
new Anisotropic ridge scheme instead of old mountain wave scheme

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e03 f.e15b03wch.F55W5SC.f09_f09.CLB2-AGW4-M-B-e03

 Same as e02 except Beljaars drag enhanced by x5
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