New evidence on Arctic sea ice trends
Dana Nuccitelli in The Guardian reports, 20th October 2014: “The National Snow and Ice Data Center has reported that this year we saw the 6th-lowest minimum Arctic sea ice extent on record. Research has shown that most of the long-term decline in sea ice, or the “death spiral” as it’s come to be known, is due to human-caused global warming.
Natural factors play a role in the extent of the Arctic sea ice as well, especially changes in weather conditions on a year-to-year basis. For example, 2012 shattered the previous record low Arctic sea ice extent because on top of the human influences, the weather conditions were ripe for a dramatic decline that year. In 2013 and 2014, weather conditions were closer to normal, so they didn’t break the 2012 record. As a result, the usual suspects have declared that Arctic sea ice is now “expanded” compared to two years ago.
The flaw in that argument is illustrated in this animated graphic I created. We can also consider Arctic sea ice extent further back in time, over the past 145 years:
Or even the past 1,450 years:
The current Arctic sea ice death spiral is clearly outside the norm and natural variability we’ve seen in recent history. Exactly how rapidly it will continue to decline is a subject of open debate among climate scientists.
Source: The Guardian, 20th October 2014. For full details see: http://www.theguardian.com/environment/climate-consensus-97-per-cent/2014/oct/20/2014-arctic-sea-ice-extent-6th-lowest-in-millennia