Articles | Volume 16, issue 19
Development and technical paper
 | Highlight paper
06 Oct 2023
Development and technical paper | Highlight paper |  | 06 Oct 2023

Emulating lateral gravity wave propagation in a global chemistry–climate model (EMAC v2.55.2) through horizontal flux redistribution

Roland Eichinger, Sebastian Rhode, Hella Garny, Peter Preusse, Petr Pisoft, Aleš Kuchař, Patrick Jöckel, Astrid Kerkweg, and Bastian Kern


Interactive discussion

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on egusphere-2023-270', Anonymous Referee #1, 28 May 2023
    • AC1: 'Reply on RC1', Roland Eichinger, 10 Aug 2023
  • RC2: 'Comment on egusphere-2023-270', Anonymous Referee #2, 19 Jul 2023
    • AC2: 'Reply on RC2', Roland Eichinger, 10 Aug 2023

Peer review completion

AR: Author's response | RR: Referee report | ED: Editor decision | EF: Editorial file upload
AR by Roland Eichinger on behalf of the Authors (10 Aug 2023)  Author's response   Author's tracked changes   Manuscript 
ED: Publish as is (14 Aug 2023) by Andrea Stenke
AR by Roland Eichinger on behalf of the Authors (28 Aug 2023)
Executive editor
Grave wave (GW) parameterisations currently used in state-of-the-art weather and climate models are based on a purely columnar approach, which does not allow for any horizontal propagation of GWs and has been identified as potential source of systematic biases in the simulation of middle atmospheric dynamics. The study by Eichinger and colleagues presents now a computationally efficient method to emulate the effects of lateral propagation of orographic GWs in climate models by horizontal momentum flux redistribution using redistribution maps derived from a GW ray-tracing model. The presented approach is an important step towards a better representation of orographic GWs in climate models, which might improve long-standing problems in atmospheric modelling.
Short summary
The columnar approach of gravity wave (GW) schemes results in dynamical model biases, but parallel decomposition makes horizontal GW propagation computationally unfeasible. In the global model EMAC, we approximate it by GW redistribution at one altitude using tailor-made redistribution maps generated with a ray tracer. More spread-out GW drag helps reconcile the model with observations and close the 60°S GW gap. Polar vortex dynamics are improved, enhancing climate model credibility.