Ocean Acidification

Recently,one of my correspondents brought up the subject of increased CO2 impacting the building of coral reefs through acidification of the ocean. I will admit that I am personally dismissive of this particular pathway. However, it is worth some discussion.

CO2 is absorbed into the upper layer of the ocean and is fairly quickly absorbed into the dissolved calcium carbonate content of sea water. This is a continuous process that with a rising atmospheric CO2 content might quite easily be expected to increase. Again though, the ocean mass is a huge sink that holds and maintains a calcium carbonate content in equilibrium with the accumulated calcium carbonate content on the ocean floor. In other words, it behaves like a saturated solution which is not likely to be much affected by a minor change in one of the variables.

There has been major variations of both CO2 content in the atmosphere and ocean uptake rates established as part of the geological record without any evidence of a radical change in reef formation which is of course the driver of this tenuous argument. At least no evidence that I am aware of. Meanwhile the carboniferous age bespoke a very high CO2 atmospheric content with a derivative ocean uptake.

I then return to the the other aspect of this acidification protocol and its effect on sea life. That is that sea life accumulates calcium carbonate through a direct ion exchange mechanism that can be mimicked with a direct current anode cathode pair. In other words, the life form energizes its environment to produce the appropriate shell. It is not dependent on the prevailing chemistry except to remain itself healthy. Before any effect was generated by this mechanism, it is a good assumption that the sea would have to become itself inhospitable.

So it is easy to see why I have been fairly dismissive of any negative effects to the ocean itself. The truth is, is that the ocean is a wonderful sink that has so far been able to handle our worst. I only get nervous over man made molecules that lack a biological pathway to breakdown.

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