In a forecast study, scientists found that 34% of the area of all Antarctic ice sheets, measuring about half a million square kilometers, could destabilize if world temperatures rose by 4 degrees. About 67% of the ice shelf surface on the Antarctic Peninsula runs the risk of destabilization under this scenario, researchers said.
Ice racks are permanently floating platforms of ice attached to areas of the coastline, formed where glaciers meet the sea from land. This can help curb the increase in world sea levels by acting like a dam and slowing down the flow of melting ice and water to the oceans.
Every summer, ice melts on the surface of ice racks and runs into smaller gaps in the snow below, where it usually freezes again. But if there is a lot of melting and little snow falling, this water would rather pool on the ice surface or flow into cracks. This causes the cracks to deepen and widen, causing the shelf to break and collapse into the sea.
“Ice shelves are important buffers that prevent glaciers on land from flowing freely in the ocean and contribute to sea level. When it collapses, it’s like a giant cork taken out of a bottle, carrying unimaginable amounts of water from glaciers in the sea can crash., “said lead author of the study, Ella Gilbert, a climate scientist at the University of Reading’s meteorology department, in a statement.
Gilbert told CNN that low-lying coastal areas, especially small island states such as Vanuatu and Tuvalu, in the South Pacific, are at greatest risk due to the world’s sea level rise.
“Coastal areas around the world, however, will be vulnerable, and countries with less available resources to soften and adjust sea levels will have worse consequences,” she said.
In the new study, which used high-resolution local climate models to predict the impact of increased melting and runoff of water on ice shelf stability, researchers say limiting temperature to 2 degrees Celsius instead of 4 degrees Celsius would make the hazardous area halve and avoid possible significant sea level rise.
The Intergovernmental Panel on Climate Change concluded in an important report that we only have until 2030 to drastically reduce our dependence on fossil fuels and prevent the planet from reaching the essential threshold of 1.5 degrees Celsius (2.7 degrees Celsius). Fahrenheit) above the pre-industrial level.
Global net emissions of carbon dioxide will have to fall by 45% by 2010 levels from 2010 levels and to reach a ‘net zero’ around 2050 to keep warming around 1.5 degrees Celsius.
“The findings underscore the importance of limiting global temperature rises as set out in the Paris Agreement if we are to avoid the worst effects of climate change, including sea level rise,” Gilbert added.
In the Paris Agreement, 197 countries agreed to the goal of keeping world temperatures ‘well below’ 2 degrees Celsius above pre-industrial levels and strive to limit them to 1.5 degrees Celsius.
Gilbert told CNN that rising temperatures mean melting is occurring more frequently and more intensively.
Researchers have identified four ice shelves that would be threatened by a warmer climate: the Larsen C, Shackleton, Pine Island and Wilkins ice shelves, which are vulnerable due to their geography, and the runoff predicted in those areas.
Larsen C is the largest remaining ice shelf on the Antarctic Peninsula, and the Pine Island Glacier has received a lot of attention in recent years because it melted quickly in response to climate change, Gilbert said.
If these ice shelves have collapsed, which is not guaranteed, the glaciers they currently hold will flow into the ocean and contribute to sea level rise – possibly ten centimeters, she explained.
The study was published Thursday in the journal Geophysical Research Letters.