![Pooled meltwater and slush on the Tracy Tremenchus Ice Shelf, which flows into the Southern Ocean. Contains modified Copernicus Sentinel data [2018], processed by Rebecca Dell](https://scienceblog.com/wp-content/uploads/2024/06/ice-shelf.jpg)
A new study reveals that Antarctic ice shelves contain twice as much meltwater as previously thought, with slush playing a major role. This discovery could have significant implications for ice shelf stability and future sea level rise predictions.
AI Unveils Antarctica’s Hidden Slush
Researchers from the University of Cambridge used artificial intelligence to map slush on Antarctic ice shelves. They found that 57% of all meltwater is held in the form of slush, with the remaining amount in surface ponds and lakes.
Dr. Rebecca Dell from Cambridge’s Scott Polar Research Institute (SPRI) explained the challenge: “We can use satellite imagery to map meltwater lakes across much of Antarctica, but it’s hard to map slush, because it looks like other things, such as shadows from clouds, when viewed from a satellite. But using machine learning techniques, we can go beyond what the human eye can see and get a clearer picture of how slush might be affecting ice in Antarctica.”
The team used optical data from NASA’s Landsat 8 satellite to train a machine learning model. This model then identified slush and meltwater lakes across 57 Antarctic ice shelves between 2013 and 2021.
Slush: A Hidden Threat to Ice Shelf Stability
The presence of slush and pooled meltwater leads to 2.8 times more meltwater formation than predicted by standard climate models. This is because slush and water absorb more heat from the sun than ice or snow.
Professor Ian Willis, co-author of the study, highlighted the potential impact: “Since slush is more solid than meltwater, it won’t cause hydrofracture in the same way that water from a lake does, but it’s definitely something we need to consider when attempting to predict how or whether ice shelves will collapse.”
As the climate warms, more meltwater forms on ice shelves, potentially leading to instability or collapse. This, in turn, contributes to sea level rise.
Dr. Dell expressed surprise at the oversight in current models: “I was surprised that this meltwater was so poorly accounted for in climate models. Our job as scientists is to reduce uncertainty, so we always want to improve our models so they are as accurate as possible.”
The research, published in Nature Geoscience, underscores the need for more accurate climate models to better predict future sea level rise. As Professor Willis noted, “In future, it’s likely that places in Antarctica that currently don’t have any water or slush will start to change. As the climate continues to warm, more melting will occur, which could have implications for ice stability and sea level rise.”
This study, supported by the European Space Agency and the Natural Environment Research Council, provides crucial insights into the complex dynamics of Antarctic ice shelves. It highlights the importance of considering all forms of meltwater when assessing the future stability of these critical ice formations.
