by Jennifer Francis, HuffPost — 01/29/2019
Why cold air plunges south
Greenhouse gas emissions from human activities have warmed the globe by about 1.8 degrees Fahrenheit (1 C) over the past 50 years. However, the Arctic has warmed more than twice as much. Amplified Arctic warming is due mainly to dramatic melting of ice and snow in recent decades, which exposes darker ocean and land surfaces that absorb a lot more of the sun’s heat.
Because of rapid Arctic warming, the north/south temperature difference has diminished. This reduces pressure differences between the Arctic and mid-latitudes, weakening jet stream winds. And just as slow-moving rivers typically take a winding route, a slower-flowing jet stream tends to meander.
Large north/south undulations in the jet stream generate wave energy in the atmosphere. If they are wavy and persistent enough, the energy can travel upward and disrupt the stratospheric polar vortex. Sometimes this upper vortex becomes so distorted that it splits into two or more swirling eddies.
These “daughter” vortices tend to wander southward, bringing their very cold air with them and leaving behind a warmer-than-normal Arctic. One of these eddies will sit over North America this week, delivering bone-chilling temperatures to much of the nation.
In other words, because the Arctic is warming so much faster than the Mid-latitudes are, the rivers of winds that separate these global regions (also known as the Jet Stream) — are starting to look more and more like this:
As the temperature differential between these regions keep ‘equalizing’, the global ‘engine’ driving these weather currents, has become less intense than it use to be. Less intense equates to a less direct planet-circling course, in our weather delivery systems.
Indeed, in other Earth-changing Climate news, there are land areas in the once-frozen North, that are being rapidly exposed to sunlight — for the first time in well over 100,000 years! Happening NOW.
by Stephanie Pappas, Live Science Contributor — Jan 28, 2019
The retreat of Arctic glaciers is exposing landscapes that haven't seen the sun for nearly 120,000 years.
These rocky vistas have very likely been covered in ice since the Eemian, a period in which average temperatures were up to 3.6 degrees Fahrenheit (2 degrees Celsius) warmer than present, and sea levels up to 30 feet (9 meters) higher.
As Scientist Francis concludes her article ...
Undoubtedly this new polar vortex attack will unleash fresh claims that global warming is a hoax. But this ridiculous notion can be quickly dispelled with a look at predicted temperature departures around the globe for early this week. The lobe of cold air over North America is far outweighed by areas elsewhere in the United States and worldwide that are warmer than normal. [See Temperature Map.]
The only hoaxing going on, is what the Oil Lobbyists has done to close our “Window of Opportunity” to make ‘meaning change’ to protect these Climate systems.
Sep 14, 2006 — NASA scientist James Hansen, widely considered the doyen of American climate researchers, said governments must adopt an alternative scenario to keep carbon dioxide emission growth in check and limit the increase in global temperatures to 1 degree Celsius (1.8 degrees Fahrenheit). ... “I think we have a very brief window of opportunity to deal with climate ...