Does dust from Antarctica make ice in clouds and influence global climate?

Clouds over the Southern Ocean around Antarctica play a major role in the planet’s climate by reflecting incoming sunlight and trapping outgoing heat energy. However, clouds in this region are poorly represented in climate models because the amount of ice in them is poorly defined. These clouds have a tendency to persist in a supercooled state, where they remain liquid despite being well below 0 C. Hence, they are very sensitive to the presence of particles like dust that can trigger ice formation. These ice-nucleating particles are therefore key to understand these clouds and the planet’s climate. At present, no one has quantified the ice-nucleating ability of dust from Antarctica, hence we are unable to determine its role in producing ice in clouds over the Southern Ocean.

In this project we will quantify the ice-nucleating activity of samples collected from across Antarctica by our colleagues from the British Antarctic Survey (BAS) as part of the CloudSense project (https://cloudsense.ac.uk), and test the ability to aerosolise this dust in our aerosol chamber, using advanced tools for measuring the size distribution of dust and then sample the dust onto filters.