Routine Melting of Arctic Ice in July

The animation shows Arctic ice extents on Day 212 (end of July) for the years 2007 to 2021 (yesterday).  Evidently, there is considerable variation year over year both on the total amount and where the ice is to be found.  The images are from MASIE (Multisensor Analyzed Sea Ice Extent) platform operated by the US National Ice Center (NIC).  More on MASIE can be read at previous post NOAA Loses 1M km2 of Arctic Ice in July

Note that in all years, some regions are open water by day 212:  Sea of Okhotsk (lower left), Bering Sea (lower center). Mostly ice free are Hudson Bay (lower right) and Barents Sea (top left).  Center left along the Russian coastline runs the Northern Sea Route for summertime shipping from Kara Sea (top left) down through the Bering Strait.  As you can see, some years the ice is still plentiful along this route, and other years are almost ice free.  This year, Laptev is largely open water, while Kara (above) and Chukchi (below) still have much ice to challenge the ice breakers.

Of interest also is the Canadian Arctic Archipelago (center right, below Greenland).  Here is found the Northwest Passage by which intrepid sailors seek transit from the Atlantic (right) through to the Pacific by way of Bering Sea.  Again, some years it is open and simple, and other years closed completely.  On day 212, 2021, CAA has more ice than average, so this year could be more challenging than in other recent years.

The graph below shows July daily ice extents for 2021 compared to 14 year averages, and some years of note.

On average, July Arctic ice declines from ~9.7M km2 down to 6.9M km2.  This year Sea Ice Index in orange (SII from NOAA) lost ice rapidly and opened up a deficit to MASIE (in cyan) of ~700M km2.  The last three weeks saw the two indices ending the month close together, slightly below average and matching 2007.  Note that both 2019 and 2020 had much lower extents at end of July.

Why is this important?  All the claims of global climate emergency depend on dangerously higher temperatures, lower sea ice, and rising sea levels.  The lack of additional warming is documented in a post Adios, Global Warming

The lack of acceleration in sea levels along coastlines has been discussed also.  See USCS Warnings of Coastal Flooding

Also, a longer term perspective is informative:

post-glacial_sea_levelThe table below shows the distribution of Sea Ice across the Arctic Regions, on average, this year and 2007.

Region 2021212 Day 212 Average 2021-Ave. 2007212 2021-2007
 (0) Northern_Hemisphere 6621487 6903677  -282190  6344860 276627 
 (1) Beaufort_Sea 899718 776180  123539  760576 139143 
 (2) Chukchi_Sea 563418 526326  37091  382350 181068 
 (3) East_Siberian_Sea 652192 745174  -92982  445385 206807 
 (4) Laptev_Sea 97962 389632  -291669  314382 -216420 
 (5) Kara_Sea 230155 159737  70418  239232 -9077 
 (6) Barents_Sea 37818 32484  5334  23703 14115 
 (7) Greenland_Sea 149142 298586  -149444  324737 -175595 
 (8) Baffin_Bay_Gulf_of_St._Lawrence 143110 136724  6387  94179 48931 
 (9) Canadian_Archipelago 594031 547883  46148  510063 83968 
 (10) Hudson_Bay 113973 151424  -37452  93655 20318 
 (11) Central_Arctic 3139007 3137899  1108  3154837 -15830 

The overall deficit to average is 282k km2, (4%) which matches the deficit in Laptev.  Other places with less than average extents are East Siberian, Greenland Sea and Hudson Bay.  Offsetting these are surpluses in Beaufort, Chukchi, Kara and CAA.  


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