10 for 10 - Arctic Sea Ice Melt Trend Continues

Every year in October the National Snow and Ice Data Center (www.nsidc.org) releases a report on the minimum sea ice extent for the current year.  This year the NSIDC announced that the minimum summer sea ice extent for 2014 was 5.02 million square kilometers.  OK, so what?

NASA satellites started monitoring sea ice extent in the Arctic Ocean back in 1979.  Satellite data are downloaded each day and sent sent to the National Snow and Ice Data Center at the University of Colorado, Boulder, for analysis.  Thirty-five years of these data are now painting a sobering picture.  Though there is a significant amount of year-to-year variability among the data, a strong trend is emerging.

Average Monthly Sea Ice Extent September 1979-2014.  

Data courtesy of NSIDC.org

The data show that there is significantly less sea ice in the Arctic now than there was only a few decades ago.  The upper end of the trend line tops out around 7.9 million square kilometers of sea ice, and the bottom end of the line reached about 4.9 million square kilometers of sea ice.  The difference?  About 3 million square kilometers of sea ice gone missing.  How much is that?  That's about the same surface area as India, the 7th largest country in the world.

NSIDC also reports that we are currently losing on average 13.3% of sea ice cover per decade and that the ten Septembers with the lowest extents happened in the last ten years!  

Bottom line?  We are progressively losing more sea ice in the Arctic.  

10 for 10?  The last ten years, the ten lowest sea ice extents, and sadly at this rate it's not likely to get better before it gets even worse.