Southern Ocean aerosols: properties, sources, and impact on cloud formation

Overview

Robust prediction of human-induced global warming and future climate requires more accurate climate models. Currently, aerosol-clouds interactions represent the largest source of uncertainty in our global climate models. To reduce this uncertainty, we need a better understanding of aerosol sources, chemical and physical properties, and processes impacting their growth to sizes where they can act as Cloud Condensation Nuclei (CCN) and interact with incoming solar radiation.

The Southern Ocean is a region of the world where climate and weather models, including the ones that inform the Intergovernmental Panel on Climate Change (IPCC) Assessment Reports, perform particularly poorly. They persistently overpredict the amount of sunlight reaching the Earth's surface over the SO, causing an overprediction of sea surface temperatures. This can be attributed to the scarcity of relevant, comprehensive in situ atmospheric observations in this remote region of the world. In 2018 and 2024 we had two 2 month long southern Ocean voyages onboard the Australian science ship Investigator and we are now getting ready for an intensive multidisciplinary land-based campaign at Kennaook/Cape Grim Global Atmospheric Watch station (Tasmania). There we will deploy a comprehensive suite of instruments (including several field-deployable mass spectrometers) to measure aerosols and their gaseous presursors.

Research engagement

As a part of this summer project the student will focus on our recent voyage (Jan-March 2024) and investigate where the airmasses that were sampled during the voyage were coming from. For that the student will use HYSPLIT trajectory model (https://www.ready.noaa.gov/HYSPLIT.php), a tool that is commonly used in atmospheric science and air quality. In terms of aerosol properties, several interesting periods have already been identified and the student will work on elucidating how the airmasses travelled before coming to the ship location.

There is also a possibility of attending a summer school that will run in the first week of Feb 2025 at Kennaook/Cape Grim station and where the participants will be introduced to the different instruments and get lectures and tutorials by the lead scientists and technicians responsible for the delivering the scientific goals of Kennaook/Cape Grim station.

Research activities

The student will be working with A/Prof Miljevic and a postdoctoral research fellow.

Skills and experience

Ideally, you should be a student with a background in either of the following: chemistry physics mathemetics earth science environmental engineering and have a strong interest in: analysis of large datasets

Start date

2 January, 2024

End date

14 February, 2025

Location

P block, level 8, GP campus

Keywords

• Atmosphere
• climate
• aerosols

Contact

Branka Miljevic,  3138 3827,  b.miljevic@qut.edu.au