AMOC and Other Climate Information ~~ dmorista

Prepared for The Class Struggle by Dmorista

Collectivist Action (“The Eco Collapse We Were Warned About Has Begun ~~ JOSÉ SEOANE”) and Newest Beginning (Is Earth Close to “The Great Dying”? ~~ Thom Hartmann) both posted important articles about the ever-looming and always-threatening developments related to Global Warming.

Hartman introduced the scientific phrase the Atlantic Meridional Overturning Circulation (AMOC) which is obscure enough that even well-informed non-specialists might have been unfamiliar with it and the concepts involved.

AMOC is part of a larger system of cold deep water currents and warm surface currents that distribute heat and cooling around the world.  Here is a map of the Complete Great Ocean Conveyor System showing where the Greenland Glacial Meltwater is flowing into the Atlantic and pushing the AMOC water flows off their current course.

The AMOC branch (that consists of the Gulf Stream and the deep cold water return current from the North Atlantic) in the North Atlantic is different and vulnerable to the meltwater from Greenland.  Neither of the two other major nodes of the Great Ocean Conveyor System has anything like Greenland, that has about 15% of the Glacial Ice on Earth, and that produces an even higher proportion of the cold dense meltwater on Earth, something like 30%.  That heavy dense water will eventually overpower the Gulfstream flows coming from the tropics and will, paradoxically, plunge Europe into a long period of very cold winters. 

The Great Ocean Conveyor System works to cool the tropical latitudes and warm the higher latitudes (in the Northern Hemisphere).  It does so in a slow massive way, the travel time for water to move throughout the system is around 1,000 years.

The other major heat distribution system are the atmospheric circulation cells.  These are THe Hadley Cells, the Ferrell (or Mid-Latitude Cells) and the Polar Cells.  Each of these giant atmospheric circulation cells carry warm and humid, or at least relatively warm air up, where it eventually reaches a height and set of conditions that cause the moisture to fall out as some sort of precipitation.  Then after traveling about 30 degrees the air descends, heating and becoming even drier.  The cells that are closest to the Equator, The Hadley Cells are the most powerful.    

The Hadley Cells carry equatorial moisture up and it falls back to earth in the relatively low equatorial latitudes.  But where their air descends, at about 30 degrees is where the world’s massive desert and semi-arid areas are located. These include the Sahara Desert, the Arabian Desert, the Gobi Desert in Eurasia, and in the Western Hemisphere the Mojave and Sonoran Deserts, in the Southern Hemisphere there are the Atacama Desert, the Kalahari Desert, and the Australian Desert. 

There are other factors that affect where Deserts and Semi-Arid regions are located, but the distribution of precipitation and dryness that is generally affected by the atmospheric circulation cells plays a large role.