A midlatitude influence on Australian monsoon bursts

Sugata Narsey, Michael J Reeder, Duncan Ackerley, Christian Jakob

Research output: Contribution to journalArticleResearchpeer-review

Abstract

The initiation of northern Australian monsoon rainfall bursts is accompanied by an increase in cyclonic circulation in the monsoon region. This study shows that the change in circulation at the start of the composite rainfall burst is predominantly influenced by midlatitude frontlike features. By exploiting the relationship between circulation tendency and the convergence of absolute vorticity flux, the circulation changes accompanying the initiation of Australian monsoon bursts is investigated. Moisture flux convergence is found to be proportional to the circulation changes in the monsoon region. Using a composite analysis it is shown that absolute vorticity fluxes through the southern boundary are by far the most important influence on monsoon burst circulation changes, with only one-third of events more closely related to other influences including the Madden-Julian oscillation. This is shown to be true throughout the wet season.

Original languageEnglish
Pages (from-to)5377-5393
Number of pages17
JournalJournal of Climate
Volume30
Issue number14
DOIs
Publication statusPublished - 1 Jul 2017

Keywords

  • Dynamics
  • Fronts
  • Madden-Julian oscillation
  • Monsoons
  • Rossby waves
  • Vorticity

Cite this

Narsey, Sugata ; Reeder, Michael J ; Ackerley, Duncan ; Jakob, Christian. / A midlatitude influence on Australian monsoon bursts. In: Journal of Climate. 2017 ; Vol. 30, No. 14. pp. 5377-5393.
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A midlatitude influence on Australian monsoon bursts. / Narsey, Sugata; Reeder, Michael J; Ackerley, Duncan; Jakob, Christian.

In: Journal of Climate, Vol. 30, No. 14, 01.07.2017, p. 5377-5393.

Research output: Contribution to journalArticleResearchpeer-review

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