A synoptic bridge linking sea salt aerosol concentrations in East Antarctic snowfall to Australian rainfall

Udy, Danielle; Vance, Tessa; Kiem, AS; Holbrook, Neil

151828 - A synoptic bridge linking sea salt aerosol concentrations in East Antarctic.pdf (8.56 MB)

A synoptic bridge linking sea salt aerosol concentrations in East Antarctic snowfall to Australian rainfall

journal contribution

posted on 2023-05-21, 10:49 authored by Danielle UdyDanielle Udy, Tessa VanceTessa Vance, Kiem, AS, Neil HolbrookNeil Holbrook

Previous research has shown that aerosol sea salt concentrations (Southern Ocean wind proxy) preserved in the Law Dome ice core (East Antarctica) correlate significantly with subtropical eastern Australian rainfall. However, physical mechanisms underpinning this connection have not been established. Here we use synoptic typing to show that an atmospheric bridge links East Antarctica to subtropical eastern Australia. Increased ice core sea salt concentrations and wetter conditions in eastern Australia are associated with a regional, asymmetric contraction of the mid-latitude westerlies. Decreased ice core sea salt concentrations and drier eastern Australia conditions are associated with an equatorward shift in the mid-latitude westerlies, suggesting greater broad-scale control of eastern Australia climate by southern hemisphere variability than previously assumed. This relationship explains double the rainfall variance compared to El Niño-Southern Oscillation during late spring-summer, highlighting the importance of the Law Dome ice core record as a 2000-year proxy of eastern Australia rainfall variability.

History

Publication title

Communications Earth and Environment

Article number

175

Number

175

Pagination

1-11

ISSN

2662-4435

Department/School

Institute for Marine and Antarctic Studies

Publisher

Nature Publishing Group

Place of publication

United Kingdom

Rights statement

© 2022. The Authors. This article is licensed under a Creative Commons Attribution 4.0 International (CC BY 4.0) License, (https://creativecommons.org/licenses/by/4.0/), which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Repository Status

Open

Socio-economic Objectives

Atmospheric processes and dynamics; Climatological hazards (e.g. extreme temperatures, drought and wildfires); Climate variability (excl. social impacts)