~ The consequences of ignoring warming Polar regions extends way beyond snow and ice lands.
~We look at one example, where lot's of people live.
And so the Arctic just had record lower sea ice extent minimum again, a few weeks after mid September minima being 2nd lowest ever. In the Arctic, this gave warmer September and October weather with a whole lot more snow and strong blizzards, nothing to worry the world about. But further South, weather patterns have changed not so favorably in some places. We look further away to the place where wildfires rage, California, because there is less rain there for a reason:
2011, 2010 are the best recent years with the least numbers of Californian wildfires, 1982 was an example taken at random. 600 mb temperatures NCEP/NCAR NOAA daily composites for October demonstrate a peculiar Arctic vortex pattern, squarish roundish with least extended planetary waves. Of particular interest is the -20 C boundary at or near deep Southern Alaska, it is in green, this is the likeliest average location of the Polar jet stream. We see this green zone being at the British Columbia Alaska coastal border. Implying a stronger Pacific flow of moist air towards most of western North America, likely favoring rain. And there was normal rain
in 2010 and 2011 for California.
We look at the wavier 2017-2018-2019 global circulation. At first glance the average -20 C green line for October looks about the same. Although overall Polar Vortex looks wavier, showing distinct planetary waves crests, this is due to a more collapsed Polar Vortex by warming from within. It is no coincidence, 2017 to 2019 have had record wildfire area outbreaks for California, costing a profound distressing fortune in lives disrupted materially and psychologically and especially for the environment alike. Now look again at the 253 Kelvin green line (-20 C). It was at Barrow Alaska October 2018, at extreme Northern Alaska, with 2017 and 2018 green line near Anchorage 700 hundred miles further North than 2010 and 2011. This Northwards repositioning of the Vortex jet stream of course means a weaker Pacific flow for the Californian coastline, suggesting less fall rains, as it is and was so (precipitation facts :https://ggweather.posthaven.com/summary-of-california-2017-2018-rainfall-season-ending-tomorrow
The Northwards shift of jet stream or the October 600 mb -20 C line movement towards the high Arctic is strictly the result of vanishing sea ice, during especially about the Arctic sea ice minima, causing massive warming feedbacks, especially for North Pacific sea surface temperatures. These fires were very predictable, because what happens in the Arctic, does not stay there. WD November 5 2019
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