Plankton cool water

A number of current coupled ocean-atmosphere climate models predict that the overturning of the North Atlantic may decrease somewhat under a future warmer climate.While this is not a feature that coupled models deal with well, its direct impact on the ocean s sequestration of carbon would be to cause a significant decline in the carbon that is stored in the deep water. This is a positive feedback, as oceanic carbon uptake would decline. Flowever, the expansion of area populated by the productive cool water plankton, and the associated decline... 

Typically, we will undertake serious action if the level of live planktonic organisms found in a cooling system reaches between 1 x 105 and 1 x 106 aerobic colony-forming units per milliliter (CFU/ml). When we compare this with a potable water supply that may contain only 20 to 200 CFU/ml, it appears to be a large number however, on a weight basis, this still represents an incredibly small amount of contamination, probably much less than the daily contaminant load from air-blown dust and soil. 

The planktonic foraminiferal response during the late Pliocene event shows the cyclic behavior, but not the overall increase recorded by the benthic foraminifera. As with the middle Miocene shift, the late Pliocene increase represents the cyclic buildup of ice sheets accompanied by deep water cooling. The tropical surface water temperatures, however, varied between 26 and 28°C. 

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