Sea ice loss increases snowfall over West Antarctica

A recent study led by Pennsylvania State University has found that as Antarctica loses sea ice due to global warming, the subsequent increase in snowfall over its ice sheets might partially offset the contributions to sea level rise. 

This research uncovers a complex relationship between sea ice loss in the Amundsen Sea, West Antarctica, and an increase in atmospheric moisture leading to heavier snowfalls. 

Subtle interactions 

According to Luke Trusel, assistant professor of Geography at Penn State and a co-author of the study, including these subtle interactions in climate models could improve predictions of phenomena like sea level rise.

Antarctica’s ice sheet is a major player in global sea level dynamics. As one of the world’s largest freshwater stores, any change in its volume has a direct impact on sea levels. Trusel pointed out that, while attention often focuses on visible processes like calving icebergs, less obvious factors, such as snowfall on the ice sheet, are equally crucial. 

“For a place like Antarctica, which is just massive, the amount of snow falling on top of the ice sheet is as important or even more important than other processes like meltwater or ice breaking off,” Trusel said.

The role of sea ice

Jessica Kromer, a doctoral candidate at Penn State and study lead author, emphasized the role of sea ice in the study. “Sea ice is significant. It reflects sunlight, aids in cooling the planet, and influences interactions between the atmosphere and ocean, including oceanic evaporation,” she argued. 

The researchers discovered that during periods of reduced sea ice, there was more moisture in the atmosphere, which condensed when reaching the colder ice sheet boundaries, leading to increased snowfall.

Sea level rise

Despite the potential for additional snowfall to slow sea level rise, the researchers caution that it is not sufficient to offset the overall trend. 

“With global warming, there’s an expectation of reduced sea ice. As sea ice diminishes, there could be increased evaporation from the ocean leading to more precipitation over Antarctica. While this might appear to offset the loss of sea ice, the implications are multifaceted. Increased snowfall in Antarctica might slow the sea level rise, but it’s essential to recognize that the ice sheet will continue to contribute to rising sea levels.”

Antarctic sea ice patterns

Kromer highlighted recent satellite data showing significant changes in Antarctic sea ice patterns. “While Arctic sea ice has been rapidly declining over the satellite record, the Antarctic experienced a slight increase until 2015, followed by a sharp decline in 2016,” she said. 

“In 2022, we witnessed a new record low, and this year’s levels are even lower, significantly below previous observations. These recent rapid changes in Antarctic sea ice highlight the urgency of understanding their causes and their potential impact on the Antarctic ice sheet.”

This study – published in the journal Geophysical Research Letters – underscores the necessity of refining climate models to accurately predict future sea level changes, particularly in representing sea ice dynamics. 

“If we aim to project future sea level changes with precision, it’s essential to enhance our models, particularly in representing sea ice dynamics,” Trusel concluded.

—

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates.

—

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.