Images of cracks on the giant icebergs in the Arctic are seen as clear evidence of the damage caused by global warming.
>>> Record Decline in Arctic Ice
However, a group of scientists from Laval University in Canada has discovered that this is not the actual cause.
One of the ice shelves may have broken off approximately 1,400 years ago, long before industrial activity began to impact our planet.
Scientists believe that the Ward Hunt ice shelf
broke apart around 1,400 years ago. (Photo: AP)
By studying sediment materials at the bottom of Disraeli Fjord in Canada, they believe that the Ward Hunt ice shelf, located on the northern coast of Ellesmere Island in Canada’s Nunavut territory, which is the largest remaining ice shelf in the Arctic covering an area of 170 square miles, once broke apart and then refroze about 800 years ago.
The ice shelves were separated by pressure from glaciers. They acted as barriers in the fjords, resulting in sediment layers appearing at the boundary between fresh water from the ice and salt water from the ocean.
The research team utilized radiocarbon dating and various other techniques to analyze the sediment layers, enabling them to reconstruct the timeline of events.
The results indicate that the ice shelf formed around 4,000 years ago and existed until it cracked 1,400 years ago. This condition continued until it refroze approximately 800 years ago. A few centuries later, around 100 years ago, the ice shelf began to shrink and has continued to decrease in size each year.
Throughout the 20th century, Arctic ice shelves lost more than 90% of their total surface area and continue to melt rapidly.
These findings were published in the Proceedings of the National Academy of Sciences.
