Scientists came to learn that the collapse of the precarious ice shelf in Antartica last March, was caused by extreme heat rushed in by an atmospheric river. The phenomenon, which scientists call “rivers in the sky” is a plume of moisture coming from the tropics, creating warm water vapor and warm air that rush to other parts of the Earth and raise temperatures to extreme levels.
Such conditions were observed in a new study of the collapse of Antartica’s Larsen A and B ice shelves in the summers of 1995 and 2002, respectively. The observations revealed that the so called “rivers in the sky” dumped rain and snow on land while also bringing on extreme temperatures that caused surface melt and disintegration of sea-ice, leading to large ocean swelling. Such conditions had destabilized the ice shelves in the Antarctic Peninsula.
Now that the climate crisis is expected to further increase the Earth’s temperature, the authors of the “rivers in the sky” study anticipate that the Antarctic’s remaining and biggest ice shelf, the Larsen C is at risk of total collapse.
The study authors from the Université Grenoble Alpes in France, used climate models, algorithms and satellite observations to determine where icebergs break off from a glacier or an ice shelf. The study’s lead author, Jonathan Wille told CNN they found out that nearly all extreme temperature events in the Antarctic Peninsula were triggered by the atmospheric rivers, The resulting temperature rise had caused 60% of the peninsula’s ice-breaking events between 2000 and 2020.
Willie further explained the ice shelves are important because they serve as barriers that keep land glaciers from flowing into the ocean, so as to prevent much larger sea level rise as climate change occurs..