It's difficult to make out, but 2014 is in 4th position as of May 31st, behind 2010, 2011 and 2012. Although most of the month wasn't very conducive for melting, 2014 has dipped 210 km3 below 2013. Still, the difference with the lowest year on the current date, 2011, went from 658 km3 last month to 805 km3. And 2012 has breezed past going from 159 km3 more at the end of April, to 697 km3 less now.
As soon as Wipneus has updated his PIOMAS graph, I will post it below.
Edit: Et voilà...
The anomaly trend line has now dropped below and significantly moved away from the linear trend line, continuing the oscillating shape we have grown accustomed to since 2010:
Looking at PICT, the crude ice thickness measure I derive by dividing PIOMAS (PI) volume numbers with Cryosphere Today (CT) sea ice area numbers, it's clear that average thickness for the ice pack has increased faster than in previous years. That this doesn't say everything is proven by the fact that 2013 has the lowest average thickness for this date. That was because CT sea ice area shot up during the second half of May last year.
Here's average thickness for May 31st in metres, with change from last month between brackets:
- 2005: 2.33 (+0.17)
- 2006: 2.31 (+0.19)
- 2007: 2.16 (+0.15)
- 2008: 2.29 (+0.25)
- 2009: 2.14 (+0.11)
- 2010: 2.04 (+0.10)
- 2011: 1.94 (+0.04)
- 2012: 1.97 (+0.09)
- 2013: 1.92 (+0.02)
- 2014: 1.98 (+0.09)
If you want to have a look at the data yourself, you can download the spreadsheet I use and update from GoogleDrive.
The Polar Science Center thickness graph more or less shows the same:
It looks like 2014 is losing some of the ground it recovered during the winter. Given some of the observations in the latest ASI update (low air and sea surface temperatures, for instance), it looks like this melting season still has a lot of work to do if it wants to become a contender for one of the medals. The weather has been becoming more conducive for melting in the last few days, but it's too early to tell what its effects will be on area, extent, and volume.
More from PIOMAS next month!
The NSIDC has also just released its monthly analysis with some ice thickness stuff towards the end. Figure 4a and 4b show IceBridge and CryoSat-2 data respectively:
New Arctic sea ice thickness quick look products from IceBridge, ESA CryoSat-2
The NASA IceBridge mission is an airborne campaign to augment and validate satellite measurements of sea ice and ice sheets. This spring, the NASA IceBridge program set a new record of 46 science flights, covering almost 150,000 kilometers (93,000 miles) of flight tracks from March 12, 2014 to April 3, 2014. This included flights over the western Arctic Ocean and north of Greenland to map sea ice thickness and snow depth.
NSIDC has published the 2014 quick look product, in addition to a new ESA CryoSat-2 derived sea ice thickness product. Thickness estimates from both products suggest large areas within the western Beaufort Sea that are 1 to 1.5 meters (3 to 5 feet) thick. The tongue of second-year ice that extends up toward the East Siberian Sea is considerably thicker, at 2 to 3 meters (7 to 10 feet) thick. In the eastern Arctic, the ice is predominantly first-year ice, and between 1 and 1.5 meters (3 to 5 feet) thick. The thickest ice is found north of Greenland and near the pole, ranging from 3.5 to 5 meters (11 to 16 feet) thick. The timely release of thickness data from IceBridge and ESA CryoSat-2 provide a valuable resource for seasonal forecasting because they provide an estimate of the ice thickness distribution in the Arctic at the beginning of the melt season.