1,000 Year Ocean Conveyor
June 15th, 02009 by Alexander Rose
Patrick Wlaters sent in this great tidbit about the oceans “thermohaline currents” driven by salinity and temperature gradients.
The ocean conveyor gets it “start” in the Norwegian Sea, where warm water from the Gulf Stream heats the atmosphere in the cold northern latitudes. This loss of heat to the atmosphere makes the water cooler and denser, causing it to sink to the bottom of the ocean. As more warm water is transported north, the cooler water sinks and moves south to make room for the incoming warm water. This cold bottom water flows south of the equator all the way down to Antarctica. Eventually, the cold bottom waters are able to warm and rise to the surface, continuing the conveyor belt that encircles the globe.
It takes almost 1,000 years for the conveyor belt to complete one “cycle.”
This entry was posted on Monday, June 15th, 2009 at 3:00 am and is filed under Long Term Science. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.
Posted on June 16th, 2009 at 1:26 pm
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Posted on June 20th, 2009 at 12:22 pm
I am not up to date on the generally recognized effects of climate change due to global warming, but some time ago one of them was that a massive influx of cold fresh water from Greenland and arctic Canada could block and stop the Gulf Stream as it moves north past Canada and turns east toward Europe. If this happens, one effect is to reduce the warming effect of the still-warm gyre waters moving south down the European Atlantic coast, but it looks like it would also stop this global current. I wonder if that has been studied?