To date, over 48,000 meteorites have been identified in Antarctica, representing about 60% of the specimens found globally.

The vast stretches of ice in Antarctica are a true haven for meteorite hunters like Maria Valdes, a researcher at the Field Museum of Natural History and the University of Chicago. The region sees the discovery of approximately 1,000 space rocks each year. The dark tones of these meteorites starkly contrast with the surrounding white ice.

“The frozen desert of Antarctica offers the perfect setting to recover meteorites—go to the right place, and any rock you find probably fell from the sky,” explained Valdes, who visited the region as part of an expedition in late 2022 and early 2023. This work was part of her research at the Robert A. Pritzker Center for Meteorites and Polar Studies at the museum. During this international expedition, the team discovered five meteorites.

“We came across a huge, isolated brown stone in the middle of an ice field. It was a little smaller than a bowling ball and quite heavy,” Valdes shared. “Even though I’ve seen and handled many meteorites in my career, finding one myself is a completely different experience.”

Each meteorite, formed from extraterrestrial bodies like the Moon, Mars, or large asteroids, tells a unique story about the solar system and its formation. However, a new study warns that the climate crisis is putting this treasure trove of scientific information at risk. Meteorites are vanishing into the ice, becoming inaccessible to scientists.

“As the climate continues to warm, Antarctic rocks are sinking into the ice at an increasing rate. Over time, this will render many meteorites inaccessible to scientists,” warned Valdes, who was not involved in the most recent research. “We are losing precious time capsules that hold clues about the history of our Solar System.”

As Earth warms, it is estimated that around 5,000 meteorites could disappear from the melting ice layers each year, according to a study published in Nature Climate Change on Monday (8). So far, over 48,000 meteorites have been discovered in Antarctica, representing approximately 60% of the specimens found globally.

Meteorites, chunks of rock that randomly fall from space into Earth’s atmosphere, are not evenly distributed across the frozen continent’s surface. Concentrations of these meteorites emerge in specific areas due to geography and climate patterns, Valdes explained.

Meteorites are particularly abundant in blue ice fields. In these regions, a combination of ice flow processes and local weather conditions removes layers of snow and ice from the surface, exposing meteorites previously buried. Wind-swept ice tends to appear blue compared to the surrounding snow.

“Over significant time periods, like tens or hundreds of thousands of years, phenomenal concentrations of meteorites can develop, reaching up to one meteorite per square meter in some places,” Valdes explained.

Researchers have mostly identified blue ice fields rich in meteorites by chance. However, to make the search more systematic, Veronica Tollenaar, a Ph.D. researcher at Université Libre de Bruxelles in Belgium, and her colleagues used a machine learning algorithm to create a “treasure map” of zones likely rich in meteorites. They considered factors such as surface temperature, slope, surface cover, and ice movement.

This research, published in January 2022 in Science Advances, identified 600 zones and suggested that 300,000 meteorites remain on the ice cap’s surface. Valdes noted in 2023 that she and her colleagues used this information to guide their search for rocks during their expedition.

“Our experience indicates that, so far, Tollenaar’s approach works only initially. Local parameters, such as topography and wind directions, which can redistribute meteorites from blue ice fields into local traps, also need to be considered,” Valdes explained.

In the new study, co-lead author Tollenaar and her team projected the loss of meteorites under different climate change scenarios, combining climate modeling with their 2022 work.

Meteorites can sink into the ice even when temperatures are below zero degrees Celsius (32 Fahrenheit). The dark rock absorbs solar radiation more easily due to its color, melting the surrounding ice. “With this heat, it can locally melt the ice and slowly disappear from the surface,” Tollenaar explained.

Harry Zekollari, a co-lead author alongside Tollenaar, emphasized that cold surface temperatures were one of four factors linked to potential meteorite clusters.

“It’s really important for it to be cold, and if the surface temperature starts to change—even from minus 12°C to minus 9°C—you’re crossing a magical threshold where you start losing meteorites,” said Zekollari, an associate professor of glaciology at Vrije Universiteit Brussel.

Under current policies, which the study predicts will result in warming of 2.6°C to 2.7°C above pre-industrial levels, researchers estimate that 28% to 30% of Antarctica’s meteorites could become inaccessible. In a high-emissions scenario, this estimate rises to 76%. The study also predicts that only at altitudes above 2,500 meters will meteorite losses remain below 50%.

Matthias van Ginneken, a research associate at the Center for Astrophysics and Planetary Science at the University of Kent in the UK, noted that the work “makes a lot of sense given how global warming appears to affect Antarctica.”

However, van Ginneken, who was not involved in the study, expressed a desire for the authors to address uncertainties in their model and conduct laboratory experiments to simulate how global warming affects meteorites, which could support the algorithm’s results.

“It’s certainly concerning, but there will still be thousands of meteorites to find each year,” he added via email.

“The main concern is the logistical aspect of searching for meteorites in Antarctica, which is already challenging today due to the continent’s isolation. If the results of this study prove true, it will force scientists to explore new areas, potentially even further from scientific bases than those commonly explored. This would make the treasure even less accessible and, therefore, require more funding and logistical support.”

Meteorites discovered in the southernmost regions of the planet have provided valuable scientific insights, as highlighted by Kevin Righter, a planetary scientist at NASA’s Johnson Space Center in Houston (USA), in a commentary published alongside the research. Although he was not involved in the new study, Righter noted that scientists recognized meteorites collected in the region in 1979 and 1981 as being from the Moon. Before these discoveries, the only available lunar samples came from the Apollo and Luna mission landing sites. Meteorite samples have provided a broader and more comprehensive sampling of the lunar surface. Additionally, other meteorites have been identified as originating from Mars.

“This recent history of research indicates that, with continued collection, it’s likely that new types of meteorites will be found—possibly including fragments of Mercury or Venus that were ejected from their surfaces after impacts,” Righter highlighted.

Righter, along with the study authors, urged intensified and prioritized meteorite collection efforts. “If meteorites are not collected quickly enough, they will represent a lost resource for present and future planetary science,” he emphasized.