Update Nov. 23
I will be resuming the ice watch in mid-December to report how observations compared to the projection below. As of Nov.22, MASIE reports 10.845 while NOAA shows 10.042.
MASIE measurements show that 2007 ice extent was lower than any year since. It is now confirmed that 2015 average annual extent will exceed 2007 by at least 230,000 km2. That difference arises from comparing 2007 annual average of 10.414 M km2 with 2015 running average through day 322 of 10.644. In the 43 days remaining in 2015, we can expect the annual average to rise to about 10.774, or 360,000 km2 higher than 2007.
At this point in the annual cycle, it is possible to project the annual average for the calendar year. The daily average presently is matching the running average for the year, so the year-end average will be increasing each day to the end of December. In the last decade, a typical year added 130k km2 to the annual average in the last 43 days.
Disclaimer: Alarmists will chafe at the word “recovery” above, and I am using it poetically to counter “death spiral” terminology. What we have seen in the last decade is a plateau in Arctic ice extent, analogous to the plateau in surface temperatures. The rise since 2007 is slight and not statistically important, just as the loss of ice from 1979 to 1994 in the NOAA dataset was too slight to count as a decline.
Arctic ice declined in the decade prior to 2007, but has not declined since.
MASIE Comparison 2014 and 2015 Day 322
|Ice Extents||2014322||2015322||Ice Extent|
As before, the measurements show that Barents and Kara Seas are the main difference between this year and last. At this point, those lesser extents are more than offset by gains elsewhere, especially in Baffin and Hudson Bays as well as BCE.
Footnote: NOAA was reporting ice extents comparable to MASIE during September and October (~100k km2 less). In November NOAA is showing a less robust recovery, ~400k km2 less for the month so far, and ~ 500k km2 less in recent daily reports.