Climate change

A new study predicts that any rise in sea level on the world’s southernmost continent will be offset by increased snowfall, associated with a warmer polar atmosphere.

Using modern methods to calculate projected changes in sea level, the researchers found that the two ice sheets of Greenland and Antarctica respond differently, reflecting their very different local climates.

The document, recently published in Geophysical Research Letters, reviews scientific, technical and socioeconomic information on climate change.

The project brought together more than 60 researchers from 44 institutions to produce, for the first time, process-based community projections of sea level rise from the ice sheets. This particular document focuses on one aspect of the overall project which is how the new generation of climate model projections used in current IPCC assessments differ from the previous generation in their impact on ice sheets.

Professor Tony Payne, head of the Bristol College of Geographical Sciences, said the team was trying to establish whether the projected sea level rise from the new generation of climate models was different from the previous generation.

“The new models generally predict more warming than the previous generation, but we wanted to understand what this means for the ice sheets. Increased warming from the new models results in more melting of the Greenland ice sheet and a higher increase sea ​​level by a factor of about 1.5 in 2100 “.

“However, there is little change in the projected rise in sea level from the Antarctic ice sheet. This is because the greater loss in mass caused by warmer oceans is offset by the gain in mass due to the increase in snowfall that is associated with the warmer polar atmosphere. ”

Recent findings suggest that society should plan for higher sea levels and match virtually all previous estimates of sea level rise, as scientists expect sea levels to continue to rise well beyond 2100, most likely at a fast pace.

Professor Payne added: “It is difficult to predict the mass balance of ice sheets from estimates of global warming and many of the processes involved require more attention.

“Finding that warmer climates do not affect the Antarctic mass balance, in particular, warrants closer examination because this is based on large changes in snowfall and sea-melt balance.”

“Interestingly, one of the main things to take away from this is that the response of two ice sheets and the impact that global warming has on them is different and highly dependent on their local conditions,” said Professor Payne. .