Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center:
A month of somewhat slowing extent increases has been reflected in the PIOMAS sea ice volume model output. Total volume growth during November 2017 was third lowest for the past decade. 2017 dips below 2011, thus regaining third position again. The difference with number two, 2012, is reduced from 1210 to 733 km3, whereas the gap with crazy winter year 2016 grew some more, from 1142 to 1482 km3.
Here's how the differences with previous years have evolved from last month:
Wipneus' version of the PIOMAS graph shows more clearly how 2017 has moved into third position:
The trend line on the PIOMAS sea ice volume anomaly graph slowly climbs further up into the positive standard deviation territory:
With a third lowest on record position at the end of November for both PIOMAS volume and JAXA sea ice extent, it's no wonder that thickness-wise 2017 is third lowest on record as well (I crudely calculate average thickness by dividing volume by extent):
The Polar Science Centre has thickness on a par with 2011, so practically third there too:
That's it for sea ice volume. As a bonus, here are some tidbits concerning the freezing season so far:
November was a reasonably 'warm' month in the Arctic, meaning it didn't freeze as hard as it did in the past, at least not everywhere. As this Zack Labe graph shows, this past November was - surprise - third less-coldest on record, north of 70° latitude:
On the cumulative-FDD-(freezing degree days)-anomaly-north-of-80°N-since-the-start-of-the-freezing-season-graph (from the CryosphereComputing website) this year is still second after 2016:
I've been playing around some more with NCEP reanalysis data (provided by ESRL). The graphs below show Arctic-wide air temps for November at the 925 hPa level since 2005 (yes, third again), as well as the temps for the four sides of the Arctic (with a map visualizing the distribution):
Temps are down compared to last year in all sectors, except on the Pacific front. Sea ice in the Chukchi is forming very late this year, very probably the latest on record. Like Brian Brettschneider from the International Arctic Research Center said in this interview last week:
Brian: Normally by this date, it’s 88 percent covered in ice. This year, it’s only 46 percent covered in ice. And that’s dramatically lower than even the second lowest year, which would be 2014, so very, very low ice coverage for this region… unprecedented.
Annie: And a record low by a wide margin…
Brian: By a very wide margin. I should say we’re talking the satellite era, which would be 1979 through present. But it’s fair to assume, and we have historical data that goes out to the late 1800s. It’s not as complete as the satellite era, but there’s really nothing even in that data set that comes close to where the sea ice is for 2017 through the end of November.
It can clearly be seen on Wipneus' regional sea ice area graph for the Chukchi (based on Uni Hamburg AMSR2 data that became available in 2012), and below it is a bar graph for November 28th based on NSIDC data:
Over on the Arctic Sea Ice Forum commenter A-Team posted an excellent animation - also using UH AMSR2 data - showing how this year's ice growth in the Chukchi Sea compares to previous years:
I don't know whether all that open water is causing the mild weather on the Pacific side of the Arctic, or whether the weather is holding up the re-freeze. Maybe they are both caused by some sort of atmospheric ridging system (like this one linked to Arctic sea ice loss that may cause more frequent and exacerbated Californian droughts in the future). During the past seven days or so a strong high pressure area has formed over the Siberian side of the Arctic, meaning the wind blows in from the Bering Strait, probably bringing warm, moist air:
So, the Chukchi is something to keep an eye on. Other than that there aren't any real irregularities. If we only look at recent winters, of course. What's going on in the Arctic, is one big irregularity. Happy holidays.