From Polar Bear Science
Posted on April eight, 2020 |
From Three-7 April this yr, sea ice round Svalbard Norway has been the best since 1988, however solely sixth or seventh highest since information started within the 1970s. Pack ice is yr surrounds Bear Island (Bjørnøya) on the southern finish of the archipelago for the primary time since 2009 at this date, and continues the sample of excessive extent and thickness of ice within the Barents Sea since final summer time.
On the third of April 2020, it seemed like the best extent on document had been reached, based on the NIS graph above. However as a result of the graph solely goes again to 1981 (see the ‘Min/Max’ dotted line), that’s not the case: it was solely the sixth highest in comparison with information that return to a minimum of 1969 (and 81,483 sq km above the 1981-2010 common).
Nevertheless, the distinction between extents on Three April 1988 (511,048 sq km) should be nearly statistically indistinguishable from Three April 2020 (507,194 sq km) as a result of it’s actually indistinguishable on a graph as crude because the one offered to the general public above. Though their archived ice charts availble on-line solely return to 1998 for April, the NIS famous on Three April 2020 by way of Twitter [my bold]:
“The final time there was this a lot #seaice round #Svalbard on at the present time of the yr was 1988, with 511,048 sq km. This yr’s extent has solely been exceeded by, in ascending order, 1988, 1971, 1977, 1969 and 1978.“
On the seventh of April, NIS famous the ice was equally seventh highest on document (79,124 sq km above the 1981-2010 common at 502,563 sq km), in comparison with information going again to a minimum of 1969.
The ice that surrounded Bjørnøya on the southern finish of the archipelago final yr in early March, which introduced bears to the island for the primary time since 2011, was passed by 21 March or so. Though 2004 had the best Svalbard extent on the finish of February (making 2020 the second-highest at that date), there was no ice wherever close to Bjørnøya in early April 2004. Whereas there was ice that far south in 2000 at Three April, in addition to in 2001 and 2006 and 2009 at that date, the presence of ice surrounding Bjørnøya in 2020 was nonetheless a uncommon occurrance in early April: observe that Bear Island isn’t even included on the Svalbard ice map for 2009, under:
We possible received’t hear about March and April guests to Bjørnøya till later within the yr.
Beneath is the worldwide ice extent at 7 April 2020. Observe that whereas ice is gone from the Gulf of St. Lawrence, polar bears seldom enterprise that far south, as can also be true for the southern Bering Sea within the western Arctic, the place the ice will possible retreat north rapidly:
Graph under exhibits how international ice extent in 2020 and 2006 at 7 April compares to the long run common (again to 1979):
March extent common for 2020 got here in increased than the final 5 years (or, because the NSIDC choose to place it, the ’11th lowest’ since 1979):