The existence of the Bahamas begins in the Sahara desert


Here's a really fascinating example of the interconnectedness of life and the importance of viewing things as systems, rather than individual events. The Bahamas are, underwater, giant mounds of calcium carbonate, part of the even larger Great Bahama Bank. That Bank, as it turns out, is not the result of local coral growth, but, instead, owes its existence to a chemistry experiment that begins in Africa's Sahara desert.

In short the authors show that when Sahara dust arrives in the Bahamas cyano-bacteria, what we used to call blue-green algae, bloom. As they bloom their photosynthesis removes CO2 from the water making the pH locally rise, alleviating ocean acidification. That blooming rise of ocean pH to a slightly more alkaline state results in what the Bahamanian’s have long called “Ocean Whitings” where the ocean becomes white like milk.

The whiting of the ocean is the result of white calcium carbonate precipitating out of solution as a solid mineral which sinks to the sea floor and accumulates in massive amounts. On the sea bed it looks like tiny pellets. That’s because it’s been reprocessed by marine worms.