Northern Hemisphere ice extents has moved above the decadal average in recent days.
(The image above shows ice extents for yesterday, day 239, from 2007 to 2017. Particularly interesting is the variation in the CAA (Canadian Arctic Archipelago), crucial for the Northwest Passage. (The region is located just north of the word “Sea” in gold.) Note that 2016 was a fine year for cruising with the passage completely open at this date. That was not the case in 2014, and this year also has places frozen solid.
Crystal Serenity is going through the Northwest Passage again this year, having left Seward Alaska on Aug. 15, 2017. She arrives at Cambridge Bay today, having traveled in the wake of icebreaker RRS Ernest Shackleton. The next part of the voyage could be challenging.
The graph of August NH ice extents shows 2017 has moved above the decadal average in recent days. (Ten-year average is for 2007 to 2016 inclusive)
This year is now 850k km2 greater than 2016 and exceeds the 10 year average by 200k km2. SII (Sea Ice Index) 2017 is also 450k km2 lower. A previous post Beware the Arctic Storms of August discussed how late summer storms have dramatic impacts, and the graph shows both 2012 and 2016 plummeting in the last ten days. By the end of the month in four days, those two years will go below 4.4M km2.