Sahara Dust Produces Massive Bahama Carbon Sink

Sahara Dust Produces Massive Bahama Carbon Sink

This post was inspired by a terrific new and  important paper that speaks to the role of Saharan dust, the iron and other mineral micronutrients it carries to the ocean, and how this results in a new explanation of the power and potency of ocean photosynthesis in regulating global CO2. Once again we find that the living ocean is not merely a chemical test tube but rather a complex living ecology. But sometimes the chemistry shines through as well or I should say the bio-chemistry.

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."