a BBC news item includes:
Science reporter, BBC News, San Francisco
The Arctic may be close to a tipping point that sees all-year-round ice disappear very rapidly in the next few decades, US scientists have warned.
The latest data presented at the American Geophysical Union Fall Meeting suggests the ice is no longer showing a robust recovery from the summer melt.
Dr Serreze’s concern was underlined by new computer modelling which concludes that the Arctic may be free of all summer ice by as early as 2040.
The new study, by a team of scientists from the National Center for Atmospheric Research (NCAR), the University of Washington, and McGill University, found that the ice system could be being weakened to such a degree by global warming that it soon accelerates its own decline.
“As the ice retreats, the ocean transports more heat to the Arctic and the open water absorbs more sunlight, further accelerating the rate of warming and leading to the loss of more ice,” explained Dr Marika Holland.
“This is a positive feedback loop with dramatic implications for the entire Arctic region.”…