Aslam, A.A. orcid.org/0000-0003-1362-0842, Schwendike, J., Peatman, S.C. orcid.org/0000-0002-2511-7649 et al. (3 more authors) (Cover date: January 2024 Part B) Mid-level dry air intrusions over the southern Maritime Continent. Quarterly Journal of the Royal Meteorological Society, 150 (759). pp. 727-745. ISSN 0035-9009
Abstract
Patterns in extreme precipitation across the Maritime Continent in southeast Asia are known to be modulated by many processes, from large-scale modes of variability such as the Madden–Julian oscillation, to finer-scale mechanisms such as the diurnal cycle. Transient mid-level dry air intrusions are an example of a feature not extensively studied over the Maritime Continent, which has the potential to influence rainfall patterns. Here, we show that these dry air intrusions originate from upper level disturbances along the subtropical jet. Mid-level cyclonic circulation anomalies northwest of Australia from December to February (DJF) intensify westerlies in the southern Maritime Continent, advecting dry air eastward. In contrast, mid-level anticyclonic circulation anomalies northwest of Australia from June to August (JJA) intensify southern Maritime Continent easterlies, advecting dry air westward. The resultant transport direction of associated air parcels is also dependent on the seasonal low-level monsoon circulation. Dry air intrusions are important in influencing low-level wind and rainfall patterns, suppressing rainfall over seas near the southern Maritime Continent in both seasons, as well as over southern Maritime Continent islands in DJF and the Indian Ocean in JJA. In both seasons there is enhanced rainfall to the east of the intrusion, where there is moist return flow to the extratropics. This study highlights the importance of synoptic-scale extratropical features in influencing meteorological patterns in the Tropics.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2023 The Authors. Quarterly Journal of the Royal Meteorological Society published by John Wiley & Sons Ltd on behalf of the Royal Meteorological Society. This is an open access article under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits unrestricted use, distribution and reproduction in any medium, provided the original work is properly cited. |
Keywords: | Deep convection; dry air intrusions; Maritime Continent; rainfall; tropical–extratropical interactions |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds) The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds) > Inst for Climate & Atmos Science (ICAS) (Leeds) |
Funding Information: | Funder Grant number Met Office Not Known Met Office P107879 NERC (Natural Environment Research Council) NE/R016739/1 Met Office SEA22_1.14FORSEA P110707 |
Depositing User: | Symplectic Publications |
Date Deposited: | 15 Jan 2024 15:35 |
Last Modified: | 21 Mar 2024 16:37 |
Status: | Published |
Publisher: | Wiley |
Identification Number: | 10.1002/qj.4618 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:207459 |