Antarctica has twice as much meltwater as previously thought
The science here is simple: The floating ice around Antarctica acts as a barrier against the glacial ice inside, keeping it cold and stable. But meltwater, at lower temperatures, can cause this shelf to collapse and lead to sea level rise. The problem? The region may contain far more meltwater than previously known..at least double.
When the summer season begins, the surface of this natural barrier melts due to the increase in temperature. This is just the surface, but huge lakes are formed there. previous studies They had shown that these surface lakes make it easier to break up ice shelves and thus raise sea levels. But it was not known exactly how much meltwater there was. And to this we have to add sleet, the soup that forms when ice melts and looks like poorly frozen gelatin. This liquid More than half of all melt water is on the Antarctic shelf, a quantity that is very significant and that also Haven’t paid attention to this yet substantially in regional climate models.
A team of scientists led by Rebecca Dale from the University of Cambridge Published in Nature Geoscience In which, using artificial intelligence techniques, they have been successful in mapping hailstorms 57 Antarctic ice shelves between 2013 and 2021 And it turned out that 57% of all meltwater is in the form of sludge.
“We can use satellite images to map meltwater lakes across much of Antarctica, but it’s difficult to map mud, because When viewed from a satellite, it looks like other things, like a cloud shadow – Dale explained in a statement -. But by using machine learning techniques, we can go beyond what the human eye can see and get a clearer picture of how hailstorms can affect ice in Antarctica.
The findings suggest that accumulated meltwater, in turn, causes 2.8 times more water formation than predicted by current climate modelsbecause it absorbs more heat from the Sun than snow or ice. Obviously, increasing these figures almost threefold would have important consequences when evaluating ice shelf stability and sea level rise.
The good news is that hail is more solid than melt water will not fracture at the same rate as lake waterbut “it’s definitely something we should consider when trying to predict how ice shelves will collapse or degrade” – Dale concludes -. “I was surprised that this meltwater was so poorly accounted for in climate models. Our job as scientists is to reduce uncertainty. In the future, places in Antarctica that currently do not have water or mud are likely to begin to change. As the climate gets warmer, will melt moreWhich could have an impact on ice stability and sea level rise.