In the movie The Day After Tomorrow, global warming caused a rapid onset of glaciation because meltwater shut down the “conveyor” current and the Gulf Stream.
For 50 years it had been assumed that the northward flowing warm Gulf Stream had a southward flowing cold counterpart deeper in the ocean. This “conveyor belt” is known as Thermohaline Circulation (THC).
One of the threats of global warming was the possibility of a “Thermohaline Catastrophe”. If too much fresh water suddenly was dumped into the North Atlantic from melting ice…the “conveyor belt” would shut down. This was thought to be a possible cause of rapid onsets of past glaciations.
This theory has taken a beating over the past few years.
According to Wallace Broecker, the father of the THC catastrophe theory, “the threat (of an anthropogenic thermohaline catastrophe) will be far smaller than previously envisioned” (Geological Perspectives of Global Climate Change edited by Lee Gerhard). Dennis Quaid’s character in The Day After Tomorrow was very loosely based on Wallace Broecker.
The best evidence for a past THC catastrophe had always been the Younger Dryas mini-ice age early in the Holocene. For quite a long time it was believed that the failure of an ice dam holding bake glacial Lake Agassiz in Canada had dumped so much water into the North Atlantic that it shut down the “conveyor belt” and caused a THC catastrophe. But then a few years ago, it was shown that the Agassiz ice dam failed well after the Younger Dryas…Testing the Lake Agassiz Meltwater Trigger for the Younger Dryas, Lowell, EOS, October 4, 2005…
Well, recently it was also determined that Pleistocene changes in ocean circulation followed and did not lead climate changes… Ice Age Ocean Circulation Reacted To, Did Not Cause, Climate Change At Glacial Boundaries, Science Daily, May 1, 2005…<a
Now it appears that there is no such thing as a “conveyor belt” current…
Cold Water Ocean Circulation Doesn’t Work As Expected
ScienceDaily (May 14, 2009) — The familiar model of Atlantic ocean currents that shows a discrete “conveyor belt” of deep, cold water flowing southward from the Labrador Sea is probably all wet.
New research led by Duke University and the Woods Hole Oceanographic Institution relied on an armada of sophisticated floats to show that much of this water, originating in the sea between Newfoundland and Greenland, is diverted generally eastward by the time it flows as far south as Massachusetts. From there it disburses to the depths in complex ways that are difficult to follow.
A 50-year-old model of ocean currents had shown this southbound subsurface flow of cold water forming a continuous loop with the familiar northbound flow of warm water on the surface, called the Gulf Stream.
“Everybody always thought this deep flow operated like a conveyor belt, but what we are saying is that concept doesn’t hold anymore,” said Duke oceanographer Susan Lozier. “So it’s going to be more difficult to measure these climate change signals in the deep ocean.”
And since cold Labrador seawater is thought to influence and perhaps moderate human-caused climate change, this finding may affect the work of global warming forecasters…LINK
That last paragraph is really funny. The only “evidence” for “human-caused climate change” comes from General Circulation Models. All of those models assumed that there was a “conveyor belt” current.
The only “evidence” for “human-caused climate change” comes from General Circulation Models. All of those models assumed that there was a “conveyor belt” current.
All of those models were already wrong…Now they are all even wronger…:))
In the meantime, the Earth continues to ignore the models and ignore the CO2…
None of the IPCC models predicted the global cooling that has occured over the last six to ten years.
CO2 does not drive climate change…
The Sun (and the stars) drive climate change…
The Sun has been very quiet for the past few years…And satellite temperature measurements show that all of the global warming from 1979-2003 has been reversed in just the last few years…