Five projects break the ice on Antarctic research

Title: Ice-ocean interactions in West Antarctica during rapid transitions in past warm climates
Main applicant: Peter Bijl, Utrecht University
Co-applicants: Francesca Sangiorgi, Utrecht University
Partners: Claus-Dieter Hillenbrand and Rob Larter, British Antarctic Survey

This project investigates how during past geologic episodes of rapid warming the ice sheets on West Antarctica interacted with the surrounding ocean. What was the role of sea ice? And did the ocean induce ice-sheet changes or the other way around? By investigating ocean sediment cores collected from near the ice-sheet, we will reconstruct icesheet and ocean changes during the Pleistocene and Pliocene, 100,000 and 3,000,000 years ago. This research contributes fundamentally to more accurate predictions of future ice-sheet melting and associated sea-level rise as a result of climate warming.

Title: Evolution of the Larsen C firn layer: a multi-decadal record of ice shelf vulnerability to atmospheric warming
Main applicant: Carleen Tijm-Reijmer, Utrecht University
Co-applicants: Keith Nicholls and Oliver Marsh, British Antarctic Survey

Ice shelves, the floating extensions of the Antarctic ice sheet, buttress the flow of grounded ice, limiting mass loss and sea level rise. Recently, the warming atmosphere caused the Larsen A and B ice shelves in the Antarctic Peninsula to catastrophically collapsed, and evidence is mounting that Larsen C, just to the south, is up next. This unique research collaboration between Utrecht University and the British Antarctic Survey sets out to observe, model and predict the viability of Larsen C, using it as testbed for ice shelves elsewhere in Antarctica.

Title: How will the unique aquatic ectotherm communities in Antarctica cope with warming and bioinvasions
Main applicant: Wilco Verberk, Radboud University
Partners: Lloyd Peck, British Antarctic Survey, Enrico Rezende, Un Pontificia Universidad Católica de Chile

Antarctica, home to unique marine biodiversity, is under threat from rising temperatures and invasions by exotic species from outside Antarctica. This project focusses on snails and crustaceans, which have adapted to a stable icy climate over millions of years, growing slowly but to impressive sizes. We investigate the thermal tolerance, growth, and species interactions of Antarctic and non-Antarctic species under current and future conditions. By predicting outcomes based on these factors we aim to understand how Antarctica's unique species might be impacted by shifts in climate and the arrival of non-native newcomers.

Title: The key role of mixotrophy in Antarctic carbon and sulphur cycles (MACS)
Main applicant: Susanne Wilken, University of Amsterdam
Co-applicants: Jacqueline Stefels, University of Groningen; Gertjan Kramer, University of Amsterdam
BAS partners: Markus Frey, Mike Meredith, Kate Hendry, Floortje van den Heuvel, Thomas Lachlan-Cope and Amanda Burson

Sea ice is retreating rapidly due to climate change, with far-stretching consequences for its inhabitants. Sea ice influences climate through impacts on carbon sequestration and production of the cloud-forming gas dimethylsulphide (DMS). The production of DMS helps microalgae to survive the cold polar winter, because the precursor of DMS acts as anti-freeze. In addition, polar microalgae may survive the darkness by feeding on small organic matter like bacteria. We want to understand these survival mechanisms, in order to predict the changes in polar ecosystems and the consequences for climate regulation, with disappearing sea ice.

Title: Firn Capacity of Antarctic Ice Shelves via Satellites Observations (FIRN-CAISSO)
Main applicant: Bert Wouters, Delft University of Technology
Co-applicants: Stef Lhermitte, Delft University of Technology and Liz Thomas, British Antarctic Survey

Firn, the compacted thick snow layer on Antarctic ice shelves, acts as sponge, storing water when the surface melts. Climate change is reducing its ‘sponginess’, so that it can store less meltwater. If too much water collects at the surface, cracks in the ice can form and increase the risk of ice shelf collapse. We will sample firn in Antarctica, and then combine this with satellite observations and climate models. From this, we will learn how much meltwater Antarctica’s ice shelves can absorb, in the past and future, and help us better understand the impacts of climate change on Antarctica.