It's already at freezing in the oceans after about 500 feet deep. Buoyancy of floating bodies is reduced in bubbled water. There's some believe that huge areas of bubbles that get released at times naturally, coming to the surface under boats, causes them to sink into the bubbly water and and disappear under the sea. Water tank experiments have shown this is possible. Anyway, these bubbles already happen naturally.
http://www.windows.ucar.edu/tour/link=/earth/Water/temp.html&edu=high
http://www.windows.ucar.edu/tour/link=/earth/Water/images/ocean_temp.html&edu=high
http://seasteading.org/seastead.org/localres/misc-articles/methane_reuters_10-22-03.html
http://stupac2.blogspot.com/2006/09/how-to-sink-ship-with-bubbles.html
I don't THINK it' n April Fool's gag...
http://www.physorg.com/news189059955.html
(PhysOrg.com) -- A Harvard physicist has proposed the Earth could be cooled by pumping vast numbers of tiny bubbles into the sea to lower ocean temperatures and increase the water?s reflectivity. The same strategy could be used in rivers and lakes to reduce evaporation.
The bubbles in turbulent water already provide ?undershine? beneath the surface, and these contribute around 0.1% of the Earth?s reflectivity, or albedo. Harvard University scientist Russell Seitz?s proposal is to use ships to pump tiny ?microbubbles,? about 0.002 mm in diameter, into the sea as they travel, in a strategy he terms ?Bright Water?. Seitz said the bubbles would, in effect, act as tiny mirrors containing air, and could be created by mixing water supercharged with compressed air with swirling jets of water. This would emulate and amplify a naturally occurring phenomenon.
Using computer modeling, Seitz discovered that a concentration of only one part per million of microbubbles can double the reflectivity of water, and could cool Earth by up to 3
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