‘Uncertain’ ice shelves in Antarctica in NWO-Large collaboration
TU Delft is joining forces with Utrecht University, the KNMI, NIOZ and the ULB (Brussels) to investigate the role of ice shelves in the Antarctic in sea-level rise. A 2.3 million euro grant has been secured for this as part of the NWO-Large investment programme. This programme is intended to strengthen and/or expand excellent, challenging and innovative research lines.
‘Antarctica is the single largest unknown in the current projections for sea-level rise, mainly because of uncertainty about how ice shelves will evolve in a changing climate’, explains Bert Wouters, a researcher at Utrecht University and TU Delft. ‘To reduce this uncertainty, our research consortium (HiRISE) will be focussing on ice shelves, and mapping them out accurately in high resolution using field measurements, satellite data and models. We will use the knowledge gained to make more accurate estimations of how the stability of the ice shelves is set to change in the coming centuries, and the possible impact this will have.
‘When satellite observations of the mass balance of Antarctica began in1992, the Antarctic Ice Sheet was more or less in balance. Now this ice sheet is one of the major causes of sea-level rise’, says TU Delft researcher Stef Lhermitte. ‘The loss of ice has more or less quadrupled in the last 25 years. This increase in the loss of mass is primarily concentrated in areas where the ice shelves have become thinner, particularly along the coast of West Antarctica. Ice shelves surround around 75 percent of the coast of Antarctica and are seen as the gatekeepers of Antarctica; they will determine the future of the Antarctic Ice Sheet to a large extent.’
In the recent IPCC report The Ocean and Cryosphere in a Changing Climate, the suspected contribution of Antarctica to sea-level rise in 2100 was estimated at 1 to 28 centimetres, but there is enormous uncertainty, which means it could be considerably more. This huge uncertainty is mainly due to our limited quantitative understanding of the processes that determine the instability of ice shelves. Many of these processes take place on a small scale, but with potentially large-scale consequences. This means it is vital that we have observations with accurate, high-resolution models. HiRISE is to tackle this by developing new concepts for models and satellite observations of the ice shelves.
The consortium sees itself as offering a unique mix of state-of-the-art expertise in field measurements, remote sensing and climate-impact modelling. The multidisciplinary team will be appointing eight PhD candidates and young post-docs, who will be working together on new techniques for monitoring and modelling the Antarctic ice shelves to give us a better picture of the possible impact of changing ice shelves in a changing climate.