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:
The 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|
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.
via Science Matters
August 1, 2021