English
 
Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
 
 
DownloadE-Mail
 Local TagsRelease HistoryDetailsSummary
  Regional model simulations of Antarctic coastal easterlies: dynamic controls and sensitivity to model configuration on synoptic timescales

Caton Harrison, T., Bracegirdle, T. J., King, J. C., Lu, H., Lock, A. (2023): Regional model simulations of Antarctic coastal easterlies: dynamic controls and sensitivity to model configuration on synoptic timescales, XXVIII General Assembly of the International Union of Geodesy and Geophysics (IUGG) (Berlin 2023).
https://doi.org/10.57757/IUGG23-4220

Item is

 

show all hide all

Basic

show hide
Item Permalink: https://gfzpublic.gfz-potsdam.de/pubman/item/item_5021658 Version Permalink: https://gfzpublic.gfz-potsdam.de/pubman/item/item_5021658_1
Genre: Conference Paper

Files

show Files

Locators

show

Creators

show
hide
 Creators:
Caton Harrison, Thomas1, Author
Bracegirdle, Thomas J.1, Author
King, John C.1, Author
Lu, Hua1, Author
Lock, Adrian1, Author
Affiliations:
1IUGG 2023, General Assemblies, 1 General, International Union of Geodesy and Geophysics (IUGG), External Organizations, ou_5011304              

Content

show
hide
Free keywords: -
 Abstract: Easterly winds encircling Antarctica influence sea ice concentrations and act as a driver of ocean currents, modifying transport of warm waters towards vulnerable ice shelves. Offshore, these winds are extremely variable on daily timescales, with low-level jets commonly forming parallel to the steep coastal slopes. We use a regional configuration of the UK Met Office Unified Model (MetUM) to investigate the dynamics of coastal easterly jets forming during two strong wind events in east Antarctica. We also test the sensitivity of these easterly jets to uncertain parameters in the MetUM simulations. Model outputs compare favourably with satellite and nearby sonde observations, though the peak wind speeds are underestimated. A momentum budget analysis reveals that although the large-scale forcing acts as a primary control on the offshore winds, a layer of enhanced baroclinicity within the lowest 1000 m is critical to explain the strength of the low-level jet. Advection of near-surface momentum from onshore (e.g. due to katabatic winds) plays a minor role. When sea ice is present, simulated offshore surface winds are quite sensitive to the parameterization of sea ice roughness, which can affect the winds directly and indirectly via its impact on low-level baroclinicity. Stable boundary layer representation also affects both the strength and structure of the jet. Only minor differences between experiments run at 4km and 12km grid lengths are found. Our results point to important and poorly constrained processes underpinning the strength and variability of the offshore coastal easterlies.

Details

show
hide
Language(s): eng - English
 Dates: 2023-07-112023-07-11
 Publication Status: Finally published
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Type: -
 Identifiers: DOI: 10.57757/IUGG23-4220
 Degree: -

Event

show
hide
Title: XXVIII General Assembly of the International Union of Geodesy and Geophysics (IUGG)
Place of Event: Berlin
Start-/End Date: 2023-07-11 - 2023-07-20

Legal Case

show

Project information

show

Source 1

show
hide
Title: XXVIII General Assembly of the International Union of Geodesy and Geophysics (IUGG)
Source Genre: Proceedings
 Creator(s):
Affiliations:
Publ. Info: Potsdam : GFZ German Research Centre for Geosciences
Pages: - Volume / Issue: - Sequence Number: - Start / End Page: - Identifier: -