Can Antarctic dust and biology be aerosolised and affect the region’s clouds and climate?

Clouds play an important role in the planet’s climate by reflecting sunlight and trapping heat within the atmosphere. However, they are poorly represented in climate models, particularly in the Southern Ocean and Antarctica. One of the major uncertainties is the amount of ice versus water present in clouds in the region, which can change the way in which sunlight is reflected and affect the lifetime of the cloud. This ice-to-water ratio can be drastically influenced by so-called “ice-nucleating particles” (INPs), aerosol particles that can trigger the freezing of supercooled water droplets in clouds. We recently demonstrated that there are multiple potential sources of INPs originating from Antarctica, including dusts, mosses, lichens, and volcanic ash via lab-based testing of samples collected from across Antarctica. However, a major question remains: can these INPs be lofted into the air and so influence clouds?

In this project we will use state-of-the-art aerosol measurement facilities at the University of Leeds to help determine whether samples from Antarctic can be aerosolised and, if so, in what particle size ranges and with what level of ice-nucleating ability. This will be achieved using the Leeds aerosol chamber with online particle sizing instrumentation and an online INP analyser: the Portable Ice Nucleation Experiment (PINE) chamber (https://www.bilfinger.com/en/pine/).