Journal article

Stratospheric ozone intrusion events and their impacts on tropospheric ozone in the Southern Hemisphere

Jesse W Greenslade, Simon P Alexander, Robyn Schofield, Jenny A Fisher, Andrew K Klekociuk

Atmospheric Chemistry and Physics | Copernicus Publications | Published : 2017

Abstract

Stratosphere-to-troposphere transport (STT) provides an important natural source of ozone to the upper troposphere, but the characteristics of STT events in the Southern Hemisphere extratropics and their contribution to the regional tropospheric ozone budget remain poorly constrained. Here, we develop a quantitative method to identify STT events from ozonesonde profiles. Using this method we estimate the seasonality of STT events and quantify the ozone transported across the tropopause over Davis (69°S, 2006–2013), Macquarie Island (54°S, 2004–2013), and Melbourne (38°S, 2004–2013). STT seasonality is determined by two distinct methods: a Fourier bandpass filter of the vertical ozone profile..

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University of Melbourne Researchers

Grants

Awarded by Australian Government's Australian Antarctic science grant program


Awarded by Australian Research Council's Centre of Excellence for Climate System Science


Funding Acknowledgements

We thank Sandy Burden for help clarifying some of the uncertainties involved in methods within this work. We also thank Clare Paton-Walsh, who identified the need to account for smoke-influenced events and provided discussions on how to go about doing so. This research was undertaken with the assistance of resources provided at the NCI National Facility systems at the Australian National University through the National Computational Merit Allocation Scheme supported by the Australian Government. This work was supported through funding by the Australian Government's Australian Antarctic science grant program (FoRCES 4012), the Australian Research Council's Centre of Excellence for Climate System Science (CE110001028), and the Commonwealth Department of the Environment ozone summer scholar program. This research is supported by an Australian Government Research Training Program (RTP) Scholarship.