Stratospheric Orographic Gravity Waves from Patagonia and the Antarctic Peninsula: Observations, Model Validation and Inter-Comparison
Abstract
Orographic gravity wave (OGW) drag is one of the fundamental physics parametrizations employed in every global numerical model across timescales from weather to climate. These parameterizations have significant influences, both direct and indirect, on the atmosphere's general circulation from the troposphere through at least the mesosphere. Despite their significant influence, observational constraints on these parameterizations are still largely lacking.
Presented here is an overview and preliminary results of a team project with the overall objective of providing new quantitative constraints for OGW drag parameterizations. Specific objectives include an evaluation of methods that quantify vertical fluxes of horizontal momentum (MF) from satellite observations via an observing system simulation experiment (OSSE), a validation of UKMO, WRF, and ECMWF models against satellite and balloon observations, and an inter-comparison of OGW properties (e.g. MF) within these models. Evaluation of satellite-based estimates of MF and model validation and inter-comparison will help to better quantify MF in the stratosphere, providing the best stratospheric momentum flux estimates for parameterizations to date. Two unique aspects of the project are that all models involved are deep, extending up to 1 Pa. The motivations for doing so was to include entire instrument weighting functions for AIRS observations, allowing direct, quantitative comparison between AIRS (and other satellite-borne) observations and the models. The second is the effort to perform an OSSE within the simulations, allowing comparison between MF from satellite-based methods within the models to the true MF in the models. Preliminary model inter-comparisons, validations, and observation- and model-based estimates of stratospheric momentum fluxes are presented.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMSA21A..03K
- Keywords:
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- 3334 Middle atmosphere dynamics;
- ATMOSPHERIC PROCESSES;
- 3337 Global climate models;
- ATMOSPHERIC PROCESSES;
- 3360 Remote sensing;
- ATMOSPHERIC PROCESSES;
- 3384 Acoustic-gravity waves;
- ATMOSPHERIC PROCESSES