The chart above from DMI shows why Arctic ice melted more slowly than average. This year the daily mean temperature never went above freezing, From now on it will only grow colder.  August is significant because it is the last month that NH ice extent declines.  Those familar with the datasets know that March monthly average is taken as the annual maximum ice extent, and September monthly average serves as the annual minimum. Importantly both months are neutral, i.e. the ice extent values are nearly the same at the month start and end.  All the melting occurs April to August, all the freezing October to February.

[ It reminds me what a Saskatchewan grain farmer told me: “Around here we only have AAA farmers”. I asked what he meant and he replied: “April to August and then Arizona.”]

The arctic ice extents are now reported through August 31, 2026, and as noted previously the wavy polar vortex had hampered ice formation with incursions of warmer southern air into the Arctic circle.  This factor receded in May and June, with July extents closing the gap with the averages. August ends with ice extents well above the 20-year average. The Northern Sea Route (NSR) goes through the Russian shelf seas of Laptev, East Siberian, and Chukchi seas on the way to Bering Strait in Beaufort Sea.

The image from  August 31 shows the Arctic Ocean core is still solid, while the Eurasian NSR now has open water on the left vertical side, including passages through Laptev (top left) and Chukchi (bottom Left).  As usual in August, Hudson Bay (bottom right) is full open water, as is Baffin Bay (middle right).  At this point Canadian Archipelago has opened up the eastern end of the NW passage, but still has extensive fast ice in Beaufort sea (bottom center). Canadian Ice Service latest conditions along the Alaskan coast include an ice warning for ships:

The chart below shows the 20-year August averages for Arctic ice extents, along with 2026, 2025 and 2007 as well as SII v.4. Note that on average during this period 1.9M km2 of ice extent is lost. In August, MASIE was above average the last 3 weeks, showing considerable surplus ice end of August.   SII v.4 continues to greatly underestimate Arctic ice extent, ending this period  ~0.5M km2 lower than MASIE, or half a Wadham in deficit.

The table below shows the distibution of ice extents on day 243 across regions of the Arctic ocean.

Region	2026243	Day 243 Ave	2026-Ave.	2007243	2026-2007
(0) Northern_Hemisphere	5320736	4960255	360481	4827899	492837
(1) Beaufort_Sea	734913	573741	161172	688338	46574
(2) Chukchi_Sea	424517	290417	134100	123559	300958
(3) East_Siberian_Sea	369883	370301	-417	311	369572
(4) Laptev_Sea	316828	174987	141840	273250	43578
(5) Kara_Sea	6471	46663	-40192	104111	-97641
(6) Barents_Sea	0	15154	-15154	9657	-9657
(7) Greenland_Sea	142412	164671	-22259	344052	-201641
(8) Baffin_Bay_Gulf_of_St._Lawrence	36105	29325	6780	37456	-1352
(9) Canadian_Archipelago	315921	297208	18713	263154	52766
(10) Hudson_Bay	16	20010	-19994	40797	-40781
(11) Central_Arctic	2972584	2976914	-4330	2941956	30628

The table shows an overall surplus of 360k km2 or 7%, and almost a half wadham greater than 2007. Many regions are close to or above the 20-year average. The seas of Laptev, Chukchi and Beaufort are in surplus. The only sizeable deficit is in  Greenland Sea. Bering and Okhotsk seas are left off the list since they are open water now as usual.

 

Illustration by Eleanor Lutz shows Earth’s seasonal climate changes. If played in full screen, the four corners present views from top, bottom and sides. It is a visual representation of scientific datasets measuring ice and snow extents.