Just the Facts says;

Just The Facts says:

Here’s some background on Earth’s Thermohaline Circulation;
http://en.wikipedia.org/wiki/Thermohaline_circulation
http://www.cmar.csiro.au/currents/global/CSIRO_Conveyor_Oceans_M.wmv

NASA’s Ocean Motion page also offers some good insights;
http://oceanmotion.org/html/impact/conveyor.htm

as does this page;
http://www.windows2universe.org/earth/Water/deep_ocean.html

this page;
http://www.womenoceanographers.org/Default.aspx?pid=28EF75D5-D130-46c0-947E-5CCBC627B0EE&id=AmyBower

and on this page;
http://web.deu.edu.tr/atiksu/toprak/ani4083.html

these visualizations were helpful;
http://web.deu.edu.tr/atiksu/toprak/den41.gif
http://web.deu.edu.tr/atiksu/toprak/den40.gif
http://web.deu.edu.tr/atiksu/toprak/den39.gif

This map shows where cold ocean water is sinking;
http://www.thewe.cc/thewei/&/&/bbc12/gulf_stream.gif

this one shows where heat is released to the atmosphere
http://www.windows2universe.org/earth/Water/images/thermohaline_circulation_conveyor_belt_big.gif

and this animation is helpful in visualizing the process:
http://www.whoi.edu/oceanus/viewVideo.do?fileid=46592&id=32693

In addition to temperature and salinity Earth’s rotation comes into play, especially around Antarctica;
http://en.wikipedia.org/wiki/File:Conveyor_belt.svg

which is also called the Antarctic Circumpolar Current;
http://en.wikipedia.org/wiki/Antarctic_Circumpolar_Current

and is “the largest ocean current.” “at approximately 125 Sverdrups”. Given that “The entire global input of fresh water from rivers to the ocean is equal to about 1 sverdrup.”;
http://en.wikipedia.org/wiki/Sverdrup

this circulation is of an amazing scale. Also Figure 2 about two third down this page;
http://www.waterencyclopedia.com/Mi-Oc/Ocean-Currents.html

offers another perspective. And this page offers technical insights on the Antarctic Circumpolar Current:
http://oceanworld.tamu.edu/resources/ocng_textbook/chapter13/chapter13_04.htm

These maps seem to indicate an interesting circulation at the North Pole as well:
http://www.whoi.edu/page.do?pid=12455&tid=441&cid=47170&ct=61&article=20727
http://www.john-daly.com/polar/flows.jpg

“The comparison suggests that the Atlantic meridional overturning circulation has slowed by about 30 per cent between 1957 and 2004.”
http://www.nature.com/nature/journal/v438/n7068/abs/nature04385.html

In this presentation on the Atlantic Meridinol overturning circulation, the chart Slide 4 seems to indicate a slight slowdown, but the alignment between data sets appears awful and the resultant divergent predictions laughable:
http://ioc-goos-oopc.org/meetings/oopc-9/presentations/monAM/Bryden_rapid4oopc.pdf

On the other hand, this article from November 29th, 2008 in Nature, is titled, “North Atlantic cold-water sink returns to life – Convective mixing resumes after a decade due to massive loss of Arctic ice.”
http://www.nature.com/news/2008/081129/full/news.2008.1262.html

The claim that it resumed “after a decade due to massive loss of Arctic ice.” seems dubious considering that there does not appear to have been a “massive loss of Arctic Ice”;
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seaice.anomaly.arctic.png

but this article from January 9, 2009;
http://www.whoi.edu/page.do?pid=12455&tid=282&cid=54347

also asserts that “One of the “pumps” that helps drive the ocean’s global circulation suddenly switched on again last winter for the first time this decade. The finding surprised scientists who had been wondering if global warming was inhibiting the pump and did not foresee any indications that it would turn back on.

The “pump” in question is in the western North Atlantic Ocean, where pools of cold, dense water form in winter and sink beneath less-dense warmer waters. The sinking water feeds into the lower limb of a global system of currents often described as the Great Ocean Conveyor (View animation (Quicktime)). To replace the down-flowing water, warm surface waters from the tropics are pulled northward along the Conveyor’s upper limb.”

The previous article were based upon this paper:
http://www.nature.com/ngeo/journal/v2/n1/abs/ngeo382.html

[Another fine example of blog science at its best, thanks to just the facts]
Filed under: In other online forums,Natural Processes,Supporting Research — by Richard Holle @ 6:02 pm on April 27, 2011

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