Update July 18, 2018

No one knows how long this divergence of surplus ice will persist, but for now 2018 Arctic ice extent resembles a hockey stick. Presently the ice is 525k km2 above 11 year average (2007 to 2017 inclusive) and ~1M km2 greater than 2007. More detailed report from July 14 below.

In June 2018, Arctic ice extent held up against previous years despite the Pacific basins of Bering and Okhotsk being ice-free. The Arctic core is showing little change, perhaps due to increased thickness (volume) as reported by DMI.

The image above shows ice extents on day 195 (July 14) for years 2007, 2012, 2017 and 2018. Note this year ice is strong on both Russian and N. American sides. Beaufort Sea and Canadian Archipelago are solid. E. Siberian and Chukchi Seas are also solid, despite early melting in Bering Sea. Hudson and Baffin bays still have considerable ice compared to other years.

The graph below shows how the Arctic extent has faired in July compared to the 11 year average and to some years of interest.



Note that 2018 started July well above the 11 year average and other recent years. As of day 195 (yesterday) ice extent is still greater than average and the years 2007 and 2017. SII 2018 is tracking well below MASIE this month, a gap of 500k km2 at this point.

The table below shows ice extents by regions comparing 2018 with 11-year average (2007 to 2017 inclusive) and 2017.

Region 2018195 Day 195

Average 2018-Ave. 2007195 2018-2007 (0) Northern_Hemisphere 8828959 8549517 279442 8355280 473679 (1) Beaufort_Sea 993219 826109 167110 845973 147246 (2) Chukchi_Sea 644989 636401 8588 576079 68911 (3) East_Siberian_Sea 1024284 950636 73648 788128 236156 (4) Laptev_Sea 492172 633149 -140977 575520 -83347 (5) Kara_Sea 438240 399007 39233 483785 -45545 (6) Barents_Sea 30629 64124 -33495 75731 -45101 (7) Greenland_Sea 285428 443318 -157890 472890 -187462 (8) Baffin_Bay_Gulf_of_St._Lawrence 489193 305230 183963 343396 145797 (9) Canadian_Archipelago 747737 719112 28626 730629 17109 (10) Hudson_Bay 619471 381783 237688 248785 370686 (11) Central_Arctic 3062425 3185383 -122959 3211275 -148850

2018 is 280k km2 above average, mostly due to Hudson and Baffin bays having surplus ice. Laptev, Greenland Sea and Central Arctic are down, more than offset by surpluses elsewhere. Since the two bays will melt out soon, the eventual annual minimum remains to be seen.