‘Heroic’ Antarctic Explorers Left Sea-Ice Clues
Log books from the early Antarctic expeditions indicate that the area of summer sea-ice around the continent has barely changed in size in a century.
(From BBC News / by Pallab Ghosh)– Researchers have studied the records of pioneering explorers, including Captain Robert Scott and Sir Ernest Shackleton.
The study suggests that Antarctic sea-ice is much less sensitive to climate change than the Arctic, which has declined dramatically.
The research has been published in The Cryosphere journal.
A century ago Captain Scott and Sir Ernest Shackleton were among those who ventured into completely uncharted territory.
They were the bravest explorers of their age. At the time, their voyages brought a totally new understanding of the Antarctic landscape. And now their records are giving scientists new data on the impacts of climate change.
Some data collected by whaling vessels suggests the extent of Antarctic summer (December, January, February, March) sea-ice was significantly higher during the 1950s, before a steep decline returned it to around six million square kilometres (average across the four months) in recent decades.
But the log books of the “heroic explorers” show that over the long term, the amount of ice has changed very little. It has merely ebbed and flowed.
Dr Jonathan Day of the University of Reading who led the study says his analysis indicates that the extent of Antarctic summer sea-ice is at most 14% smaller now than during the early 1900s.
“The Antarctic sea-ice a hundred years ago was fairly similar to what it is today. That is not much if you contrast this with the Arctic which has lost 26% of its extent,” he told BBC News.
Read the full article here: http://www.bbc.com/news/science-environment-38085147