Arctic sea ice collapse - 07/31/2015

Arctic Sea Ice Collapse Threatens - Update 2

Arctic News,

31 July, 2015

The image below shows sea surface temperature anomalies in the Arctic on July 30, 2015.

Not surprisingly, Arctic sea ice took a battering. The last bit of thick (5 m) sea ice in the Canadian Archipelago, which became dislodged on July 8, 2015, has meanwhile all but disappeared. This was discussed in more detail in a recent post and is also illustrated by the 30-day Naval Research Laboratory animation below.

The situation at the northern tip of Greenland doesn't look much better, as illustrated by the image below.

The thicker multi-year sea ice typically survives the melting season, giving the sea ice strength for the next year. Without multi-year sea ice, the Arctic will be in a bad shape in coming years.

So, will the sea ice collapse this year? Firstly, consider that sea ice volume now hasn't been this bad for any day in July since records began. Also, sea ice extent around this time of year was worse only in about four years, i.e. in 2007, 2010, 2011 and 2012. Furthermore, sea surface temperatures are very high, with an El Nino that is still gaining in strength, so sea ice extent looks likely to take a battering over the next few weeks. With that in mind, take a look at the image below.

The image shows a trendline (shaded area) based on satellite data from 1979-2014, with annual minimum volume figures calculated by PIOMAS. The shaded area points at a total disappearance of the sea ice as early as September 2018. 

The width of the shaded area reflects natural variability, but natural variability could be wider than that, as illustrated by the fact that minimum volume in the years 2007, 2010, 2011 and 2012 was lower than the shaded area. In other words, disappearance of the sea ice could occur even earlier than September 2018 and if things get really bad, collapse could even occur as early as September this year.

The situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan.