Climate scientists are saying 2014 is on track to be the hottest year on record, but it’s also been a record year for global sea ice coverage.
Global sea ice coverage hit the highest coverage since 1988 during December 2014 — the fourth highest global sea ice extent ever recorded for that time. Most of this has come from huge expansions of Antarctic sea ice during the South Pole’s winter, but scientists have recently acknowledged that Arctic sea ice is looking more stable than was previously thought.
Surface temperature readings suggest 2014 could be the “hottest year on record,” but what’s happening with global sea ice extent has some scientists stumped. Others have blamed record sea ice extent in Antarctica on global warming.
“It’s not expected,” John Turner, a climate scientist at the British Antarctic Survey, told The Guardian. “The world’s best 50 models were run and 95% of them have Antarctic sea ice decreasing over the past 30 years.”
Turner shouldn’t have been surprised. Contrary to most models, Antarctica saw record levels of sea ice coverage in October this year, breaking 7.7 million square miles for the first time since 1979.
According to the National Oceanic and Atmospheric Administration, sea ice extent in the Northern Hemisphere covered four million square miles, which is about 5.7 percent below the 1981 to 2010 average, but the high ice coverage since 2008. Arctic sea ice grew at a “near-average” rate, according to NOAA, gaining 2.15 million square miles during November.
Southern Hemispheric sea ice covered 6.4 million square miles in November 2014, the eighth largest sea ice extent for November ever recorded. In all, Antarctic sea ice coverage is increasing at a rate of about one percent per decade, according to NOAA.
In November, NOAA says global sea ice coverage was 10.4 million square miles — the 13th smallest level of coverage on record.
While global sea ice extent was lower than normal in November, it jumped up to the fourth-highest level recorded for 348 days into the year at about 9.5 million square miles. But as the Antarctic melts for the summer and the Arctic expands for the winter, what can we expect from sea ice coverage?
Scientists say as temperatures get hotter due to increasing levels of carbon dioxide in the atmosphere, the Arctic will continue to shrink until it completely disappears. Some scientists even argue the Arctic could disappear altogether in our lifetimes.
“We have not seen an ice free period in the Arctic Ocean for 2,6 million years. However, we may see it in our lifetime,” said Jochen Knies a marine geologist with the Geological Survey of Norway who recently authored a study on the issue.
In the early 2000s scientists and environmentalists, including former Vice President Al Gore, said the Arctic could be ice-free by 2013. That has obviously not happened yet.
But even more startling to scientists is the fact that the Arctic seems to be stabilizing and not melting nearly as fast as previously predicted.
Arctic sea ice volumes reached their second-highest levels since 2010, according to the European Space Agency, with sea ice volumes for this fall averaging 10,200 cubic kilometers, compared — down from 2013 levels, but up significantly from 2011 and 2012 levels.
Two cool summers have prevented Arctic ice from melting and allowed pack ice to accumulate, allowing the north pole to grow. Scientists still say it’s in a long-term decline, but note the Arctic is much more resilient than previously thought.
“What we see is the volume going down and down, but then, because of a relatively cool summer, coming back up to form a new high stand,” Rachel Tilling with the UK’s Nerc Centre for Polar Observation and Modelling at University College London, told BBC News.
“So, what may be occurring here is a decline that looks a bit like a sawtooth, where we can lose volume but then recover some of it if there happens to be a shorter melt season one year,” she said.