Satellite imagery of the January 25, 2008 atmospheric river landing, which triggered the disintegration of onshore fast ice in the bays of Larsen A and Larsen B, was visible five days later. Image by Jonathan Wille
One study showed that between 2000 and 2020, 60 percent of the iceberg disintegration events surrounding the Larsen Ice Shelf on the Antarctic Peninsula (which would form new icebergs) were triggered by extreme atmospheric conditions. The study argues that the same process could put the Larsen C Shelf at risk of collapse under future warming projections. The study was published April 14 in Communications – Earth and the Environment.
The antarctic ice shelf collapse event is thought to have accelerated continental ice loss, contributing to sea level rise. The “atmospheric river” is a narrow band of high humidity that moves like a river in the atmosphere. These “currents” originate in subtropical or mid-latitudes and cause heat waves, melting sea ice and ocean surges, which can lead to icebergs collapsing and ice shelves collapsing.
In recent decades, the Larsen A and Larsen B ice shelves on the Antarctic Peninsula have collapsed sharply in 1995 and 2002, respectively. These events are thought to be related to melting ice and ocean wave-related stresses brought by storms.
To clarify the impact of atmospheric rivers on the Antarctic ice shelf, Jonathan Wille and colleagues at the University of Grenoble/National Centre for Scientific Research in France identified 21 Larsen Ice Shelf collapses and collapses between 2000 and 2020. Using an atmospheric river detection algorithm, the authors found that 13 of the 21 collapse and collapse events had occurred in the previous 5 days when powerful gas rivers had landed.
The authors argue that future ice sheet stability models need to include extreme conditions for short-term atmospheric behavior, rather than relying solely on average conditions. (Source: China Science Daily Feng Lifei)
Related paper information:https://doi.org/10.1038/s43247-022-00422-9