Weakening is the most severe threat to the oldest, hardest, and strongest Arctic sea ice.
The Arctic sea ice has been declining dramatically over the past 40 years. However, polar scientists believe that a region called the "Last Ice Area", was resistant to melting as the planet warms. New research in Geophysical Research Letters has shown that a hole almost the size of Rhode Island was created in 2020. This means that even areas with strong ice 15 feet thick or more are becoming increasingly vulnerable to the warming climate.
Mashable's Arctic scientist Kent Moore said that "The scary part is that this area might not have the resilience we think it does." Moore, a professor of Physics at the University of Toronto Mississauga, led the research.
The Last Ice Area stretches from northern Greenland to the Canadian Arctic Archipelago (the Canadian islands above Canada's continental mainland). The ice grows thicker and more robust as it clumps together between the islands. Even though almost all Arctic ice melts every summer, possibly sometime around mid century as Earth continues to warm, the Last Ice Area and the unique life it supports may still be present. It is now unclear how much ice may remain.
Moore stated that the area is in transition to thinner ice.
Below are satellite images from NASA showing the 1,160-mile hole (called a "polynya") that formed in the Arctic seaice above Canada's Ellesmere Island in May 2019. Strong storms were able to overcome the thinned sea ice.
"Thinner ice is more easily moved about or broken up by strong storms and high winds. Large waves are also easier to break apart," stated Zachary Labe, an Arctic researcher from Colorado State University. He was not involved in the research. "Arctic sea-ice is getting thinner throughout the Arctic Ocean and every month of the calendar year."
"This is only one indicator of the dramatic changes occurring in the Arctic due to climate change caused by humans."
Labe said, "This is only one indicator of how climate change caused by humans is dramatically changing the Arctic. There is a shift from older and thicker to younger and thinner Arctic ice."
In 2021, the record-breaking low for older multiyear ice was reached.
Scientists found a large polynya (right), north of Ellesmere Island, in May 2020. They also discovered smaller holes (left). Credit: NASA EOSDIS Worldview
The May 2020 large polynya was the largest ever seen by polar scientists in the Last Ice Area. Moore, the study's leader, looked at satellite footage from earlier years and only saw two instances of polynyas in that area, one in 1988 and one in 2004. Scientists have more data on the 2004 event. However, the wind gusts were stronger than in 2020. The hole, however, was smaller.
Walt Meier, a Senior Research Scientist at the National Snow and Ice Data Center, said that "the difference now is the ice thinner overall." He was not involved in the research.
Moore, the study's author and Meier both suggested that as the Earth heats up, more large holes could open in the Last Ice Area.
The greater Arctic has significant implications for sea ice loss and thinning:
Both the Arctic and the rest of the world are experiencing profound changes. Even the Last Ice Area is not immune to these changes.
Moore stated that "The planet's changes are occurring faster than we thought."
