Australian Atmospheric Rivers

Lead researcher: Kara Borthwick

This research aims to investigate the spatial and temporal impacts of landfalling Atmospheric Rivers (ARs) on Australian precipitation. ARs are typically defined as elongated, narrow, water vapour-rich corridors which transport large volumes (over 90%) of water vapor poleward from areas of high sea-surface temperatures. As such, ARs play vital roles in the global water cycle and are significant influencer of regional weather and hydrology across the midlatitudes. They have increasingly been studied in connection to extreme precipitation events, however, the majority of this research has taken place in the Northern Hemisphere (particularly western Europe and the west coast of North America).

While no research has been conducted on the explicit impact of landfalling ARs on Australia, there have been numerous studies on the Northwest Cloudband (NWCB) which exhibits characteristics similar to ARs. This study will therefore attempt to expand on previous NWCB research to provide a comprehensive investigation into landfalling ARs in Australia and their influence on the Australian climate. High resolution ERA-5 reanalysis data will be used to identify and map areas of high water vapour transport across Australia, from which ARs may be identified. Weather station data will also be used to link the observed climatology aloft with the associated surface conditions.

Satellite composite image of integrated water vapor around the globe showing several prominent ARs, NOAA (UC San Diego, 2011).