Extensive wet episodes in Late Glacial Australia resulting from high-latitude forcings

Date

2017-03-08

Authors

Bayon, Germain
De Deckker, Patrick
Magee, John W.
Germain, Yoan
Bermell, Sylvain
Tachikawa, Kazuyo
Norman, Marc D.

Journal Title

Journal ISSN

Volume Title

Publisher

Nature Publishing Group

Abstract

Millennial-scale cooling events termed Heinrich Stadials punctuated Northern Hemisphere climate during the last glacial period. Latitudinal shifts of the intertropical convergence zone (ITCZ) are thought to have rapidly propagated these abrupt climatic signals southward, influencing the evolution of Southern Hemisphere climates and contributing to major reorganisation of the global ocean atmosphere system. Here, we use neodymium isotopes from a marine sediment core to reconstruct the hydroclimatic evolution of subtropical Australia between 90 to 20 thousand years ago. We find a strong correlation between our sediment provenance proxy data and records for western Pacific tropical precipitations and Australian palaeolakes, which indicates that Northern Hemisphere cooling phases were accompanied by pronounced excursions of the ITCZ and associated rainfall as far south as about 32°S. Comparatively, however, each of these humid periods lasted substantially longer than the mean duration of Heinrich Stadials, overlapping with subsequent warming phases of the southern high latitudes recorded in Antarctic ice cores. In addition to ITCZ-driven hydroclimate forcing, we infer that changes in Southern Ocean climate also played an important role in regulating late glacial atmospheric patterns of the Southern Hemisphere subtropical regions.

Description

Keywords

millennial-scale, cooling, Heinrich Stadials, Northern Hemisphere, climate, global, ocean, atmosphere, latitudinal shifts, intertropical convergence zone (ITCZ)

Citation

Source

Scientific Reports

Type

Journal article

Book Title

Entity type

Access Statement

Open Access

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