~Again a rare sight, contrary to usual water engulfment, sea ice melts in the middle of a pack
~This loop offers an explanation of the warm High over the Arctic Ocean, sea ice on the Russian side of the Pole is much thinned.
Laptev sea ice melt speeds continue to impress, at right we have astounding example, usually sea ice melts when the ice pack is scattered, and pans of ice are prey to surrounding warm surface water. Not in this case, sea ice is melting from within the pack. The loop sequence below captured the jutting ice pack at centre (right);
This middle of Pack melting is unusual, but strongly suggests very thin sea ice. NASA EOSDIS July 15-19 2020. Now this helps explain the stubbornly persistent High pressure over the Arctic Ocean. Usually at what I call "Arctic switchover" a winter/summer switching of roles occurs between anticyclones and lows, whereas cyclones tend to gravitate where its coldest, as opposed to Highs which tend to place themselves at the warmest spots, top of Greenland excluded due to obvious reasons. Switchover 2020 occurred in good time at about mid June, but at end of June appeared this anticyclone where a cyclone should be. One explanation was very hot advection from Siberia, the other reason is that the sea ice from Pole to Russia is exceptionally thinner. This would allow a High to settle over sea ice, having a surface always colder than land, but thinner sea ice has another player, thermal radiation from the underlying sea may very well be the key in allowing this High to exist, an Arctic High pressure system may be stable if literally underlying heat input is similar to land. WD July 19, 2020
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