At a Glance
- Atmospheric rivers (ARs) can both accelerate ice melt through rainfall and help slow ice loss by depositing significant snowfall on the Greenland Ice Sheet (GrIS).
- A major AR dropped 16.1 billion tons of snow on Greenland, temporarily offsetting annual ice loss by 8% and delaying summer melt by 11 days.
- Scientists used firn core sampling to track snow accumulation and analyzed isotopic composition to confirm that the snow originated from the AR.
- While ARs can temporarily increase ice reflectivity and reduce heat absorption, continued warming may shift ARs to bring more rain instead of snow, accelerating ice loss.
- The study highlights the complex role of ARs in Arctic climate systems, stressing the need for further research to predict future impacts on polar ice sheets.
A new study has found that atmospheric rivers (ARs) can have both positive and negative impacts on the Greenland Ice Sheet (GrIS). These long bands of moisture, typically linked to increased rainfall and accelerated ice melt, were once only considered harmful to Arctic ice. However, the study showed that ARs can also bring significant snowfall, which can help slow down ice loss. In March 2022, an AR dropped massive snow on Greenland, temporarily offsetting the region’s annual ice loss by 8%, the study reports.
The research team, led by Hannah Bailey from the University of Oulu, used firn core sampling to analyze the snow accumulation in southeastern Greenland. They could track snow from the AR by extracting a 15-meter-long core from the snow and examining its isotopic composition. This snow fell in two stages, starting with 11.6 billion tons of snow on March 14 and another 4.5 billion tons in the following days. These findings demonstrated how a large snowstorm could contribute to Greenland’s ice mass, delaying the typical onset of summer melt by about 11 days.
Although ARs are generally known for their adverse effects, such as causing higher temperatures and more rain that accelerate ice loss, this study suggests that they may also play a role in replenishing snow on the ice sheet. The additional snow from the AR helped to increase the snow’s reflectivity (albedo), which reduced the amount of heat absorbed by the ice. This could delay the melting process, offering temporary relief for Greenland’s ice sheet. However, experts caution that with continued warming, the ARs may increasingly bring rain rather than snow, which would speed up ice loss.
The study’s findings highlight the complex role that ARs play in Arctic climate systems. While they may provide short-term benefits by adding snow, future climate change could shift ARs to bring more rain, which would exacerbate Greenland’s ice melt. This research is important for understanding the broader impacts of climate change on polar regions and helps researchers predict how such events may evolve.
Further details from the study can be found in the journal Geophysical Research Letters.
References
- Dzombak, R. & American Geophysical Union. (2025, March 4). Intense atmospheric rivers can replenish some of the Greenland Ice Sheet’s lost ice. Phys.Org; American Geophysical Union. https://phys.org/news/2025-03-intense-atmospheric-rivers-replenish-greenland.html
- Bailey, H., & Hubbard, A. (2025). Snow mass recharge of the greenland ice sheet fueled by intense atmospheric river. Geophysical Research Letters, 52(5), e2024GL110121. https://doi.org/10.1029/2024GL110121
