SOURCE: The Guardian
DATE: January 8, 2017
SNIP: Something is happening to the floating sea ice of the Arctic, other than the well-documented retreat in its surface coverage each summer. Scientists are finding that Arctic sea ice is getting younger and thinner, which is set to continue in March, when US research reveals the winter maximum, and September, when it reveals the summer minimum, making it more vulnerable to a catastrophic and unprecedented break-up.
Nasa researchers have found that the thicker multi-year ice, which has survived several summer melt seasons, is being rapidly replaced by thinner, more ephemeral one-year ice formed over a single winter. This change makes the polar region increasingly vulnerable to storms that could smash their way through the final remnants of thinner, one-year sea ice, making a completely ice-free summer in the Arctic increasingly likely.
An unpublished study of changes to the multi-year ice over the past few decades has revealed that a part of the Arctic that should be a “nursery” for older ice has in recent years turned into a “graveyard”. Instead of multi-year ice forming within the Beaufort Gyre, a huge circular movement of ice off the coast of northern Alaska and Canada, it is now melting away within this critical region.
Computer models in the past predicted the first sea ice-free summers in the Arctic occurring mid-century, but these models have assumed a smooth loss of ice as it melts, rather than a catastrophic break-up. Now many scientists predict the first summers free of Arctic sea ice could occur within the next 10 to 15 years.