The 2015 "Arctic Report Card" has been released by NOAA, America's National Oceanic and Atmospheric Administration. In case you haven't guessed the gist of the report, here are a few highlights:
Not only is the ice winnowing away, it is becoming younger – Noaa’s analysis of satellite data shows that 70% of the ice pack in March was composed of first-year ice, with just 3% of the ice older than four years. This means the amount of new, thinner ice has doubled since the 1980s and is more vulnerable to melting.
The report card – compiled by 72 scientists from 11 countries – noted sharp variations in conditions in the northern part of the Arctic compared to its southern portion. The melting season was 30-40 days longer than the long-term average in the north but slightly below average in the south, suggesting that changes to the jet stream, causing colder air to whip across the southern part of the Arctic, are having an impact.
Noaa said warming in the Arctic is occurring at twice the rate of anywhere else in the world – a 2.9C (5.2F) average increase over the past century – and that it is certain climate change, driven by the release of greenhouse gases, is the cause.
“There is a close association between air temperature and the amount of sea ice we see, so if we reduce the temperature globally it looks like it will stabilize the Arctic,” said Dr James Overland, oceanographer at Noaa.
If you're interested in charts and photographic depictions of the year that was in the high Arctic, you can find them here. Sorry, I couldn't bring myself to post another picture of a forlorn polar bear marooned on an ice floe.
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