Arctic cyclones can break up and reshape the Arctic sea-ice cover and can be expected to do so more readily as the ice grows thinner due to anthropogenic climate change. Processes driven by Arctic cyclones can enhance the rate of melting of the ice and increase its export out of the Arctic. The record minima in sea ice extent in 2012, which was partially attributed to the presence of an Arctic cyclone. However, despite their importance, Arctic cyclones have remained relatively un-examined. We hypothesise that surface coupling (interactions between the ocean, sea ice and atmosphere) play a crucial role in determining the life cycle of Arctic cyclones, and the effect they have on the sea ice.

In ARIA we will take an important step towards understanding the role of sea ice-atmosphere interactions during the passage of cyclones, and how they might be expected to change in the future. We will quantify the dynamical feedback between the sea ice and atmosphere using a cutting-edge sea-ice model and a state-of-the-art atmospheric model. We will then evaluate the latest generation of climate models (CMIP6) to determine how well they reproduce the underlying conditions, and what is lost in the climatology by failing to resolve these processes. In particular we will focus on the impact cyclones have on the sea-ice volume, both in the short-term response and how it affects the inter-annual variability and overall decline observed in recent decades. The project results will therefore directly contribute to addressing the World Climate Research Programme’s grand challenge on the melting cryosphere.