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Fraser
2017-Jan-03, 10:20 PM
Planet Earth has gone through several "ice ages", where dropping temperatures has led to the expansion of ice sheets and glaciers.
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danscope
2017-Jan-04, 12:34 AM
Hmmm..... no mention of the 1200 pound gorilla in the room: The Thermohaline Circulation - The Great Ocean Conveyor Belt.
The oceans are the greatest heat sink. It operates as a function of salinity. As it travels great distances, it becomes concentrated in salinity and eventually becomes so much heavier than surrounding waters that it sinks , to return as an oceanic bottom river to
well up thousands of miles to the south and repeat the process. If that process becomes disturbed by severe global warming, such that melting glacial ice dilutes the high salinity river of current, that conveyor can stop!!!!!!!!!!!!!!!!!! It no longer delivers heat to the northern polar regions, and an age of severe ice build up will follow.....perhaps for thousands of years , and the arctic ice sheet advances south like a great bulldozer. The information is in the ice.

profloater
2017-Jan-04, 10:38 AM
How much work has been done on the deep ocean saline rivers as models? They are presumably moved by the tides and accelerated by coriolis as their latitude rises, then squeezed through the land chicanes producing upward lift. That would be why the tectonic state of the continents is so important, historically. Freshwater melt would not sink deep into the high saline region I would think, because the salinity density is quite a lot higher than fresh water. There could be a sharp halocline at depth but mixed by that tidal action.? The Arctic is especially swished by the funnelling of the land north of the Atlantic.

danscope
2017-Jan-04, 08:58 PM
Hi, Profloater. Good questions. I wonder how those factors interact with the timeline for advanced Ice sheet melt , followed by
failure in the thermohaline cycle , and can they be factors in reversal of the same severe ice age?