How did sabre-toothed tigers acquire their long upper canine teeth?
A study led by ULiège enriches our understanding of the Earth's past and documents the mechanisms leading to evolutionary convergence.
Global warming is making meteorites disappear, and with them, our extraterrestrial knowledge... A study led by the ULB's Glaciology Laboratory (GLACIOL) and in which the Climatology Lab of the University of Liège took part, which has just been published in Nature Climate Change, has measured this unexpected impact of climate change, which is hampering our knowledge of the solar system.
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ntarctica is the world's most prolific site for collecting meteorites - unique samples of extraterrestrial bodies - with over 60% of the 80,000 meteorites found on Earth having been collected from the ice sheet's surface. These objects contain a vast amount of information about our solar system, enabling us to understand, for example, the appearance of life on Earth or the formation of the Moon.
An analysis based on data identifying meteorite-rich sites in Antarctica shows that, due to global warming, many extraterrestrial rocks are disappearing from the surface by sinking into the ice sheet. At present, it is estimated that around 5,000 meteorites become inaccessible each year (compared with the 1,000 discovered each year).
A study conducted by scientists from the Université Libre de Bruxelles, ETH Zurich, WSL Birmensdorf, Vrije Universiteit Brussel, Université de Liège and Université Grenoble-Alpes has highlighted the responsibility of global warming in the rapid disappearance of these meteorites. "Scientific research into the future of Antarctica focuses mainly on assessing the impact of global warming on our regions, particularly its contribution to sea-level rise," explains Christoph Kittel, a researcher at the ULiège Climatology Laboratory. However, this study shows that climate change is not limited to consequences such as rising sea levels or changes in biodiversity. They can also have more unexpected repercussions, such as exploring our universe through meteorite research."
Using artificial intelligence to combine satellite observations of the continent and climate projections made with the help of the MAR model developed by researchers at ULiège, the scientists have calculated that for every tenth of a degree increase in air temperature on a global scale, 5,100 to 12,200 meteorites disappear from the surface of the ice sheet. By 2050, around a quarter of meteorites will have disappeared, and this figure could rise to three-quarters by the end of the century, depending on future greenhouse gas emissions.
Even when ice temperatures are well below zero, dark meteorites heat up so much in the sun that they can melt the ice on which they rest," explains Veronica Tollenaar, a doctoral student at ULB's Glaciology Laboratory (GLACIOL). As a result, the hot meteorite creates a local depression in the ice and, over time, disappears entirely beneath the surface. As atmospheric temperatures rise, the surface temperature of the ice increases, which intensifies this process, as less heat is needed from the meteorites to melt the ice locally."
It is estimated that at least 300,000 meteorites remain on the surface of the Antarctic ice sheet. The study reveals that, due to climate change, around 5,000 meteorites are disappearing every year, five times faster than the rate at which they are being collected.
Tollenaar V., Zekollary H., Kittel C., Farionotti D., Lhermitte ., Debaille V., Goderis S.; Claeys P., Joy KH and Pattyn F., Antarctic meteorites threatened by climate warming, Nature Climate Change, 2024. https://hdl.handle.net/2268/316020
A study led by ULiège enriches our understanding of the Earth's past and documents the mechanisms leading to evolutionary convergence.
The SPECULOOS project, led by the University of Liège, has revealed the existence of an Earth-sized planet around SPECULOOS-3, a nearby star similar in size to Jupiter and twice as cold as our Sun.
Co-discovered by researchers from the University of Liège, this exoplanet is larger but seven times less massive than Jupiter and is the second least dense planet discovered to date.