Our oceans are dying

(via Daily Kos)

From Daily Kos:

Oxygen levels are dropping and ocean waters are acidifying at the fastest rate in at least 300 million years when the greatest marine extinction in earth's history took place according to The State of the Ocean Report 2013 written by an international panel of marine scientists.

Today's explosive increase in human CO2 emissions and warming of the oceans are recreating the conditions of the great Permian extinction 300 million years ago when massive volcanic eruptions in Siberia triggered the release of enormous amounts of stored carbon. A leading theory is that deoxygenation and acidification of the oceans led to the bacterial production of toxic hydrogen sulfide gas which poisoned species dependent on oxygen. By the end of this natural catastrophe 90% to 95% of all marine species were extinct. The biodiversity of the oceans took 30 million years for to recover.

the scale and rate of the present day carbon perturbation, and resulting ocean acidification, is unprecedented in Earth’s known history. Today’s rate of carbon release, at approximately 30Gt of CO2 per year, is at least 10 times faster than that which preceded the last major species extinction (the Paleocene Eocene Thermal Maximum extinction, or PETM, ca. 55 million years ago), while geological records indicate that the current acidification is unparalleled in at least the last 300 million years. We are entering an unknown territory of marine ecosystem change, and exposing organisms to intolerable evolutionary pressure. The next mass extinction event may have already begun.

Human CO2 emissions directly cause both global warming and ocean acidification. But that's just the beginning. Mixing tends to decline in warming waters because a warm fresh surface layer is substantially lighter than colder middle and deep water. The surface layer tends to float and not mix. Organic carbon is always falling from the surface to deeper waters. Bacteria oxidize the fallen carbon to CO2. This process reduces oxygen levels and increases the acidity of the water. When the rate of mixing declines the residence time of water in a layer increases, so acidity levels tend to rise and oxygen levels drop in layers below the surface as the climate warms.

There's lots more, including examples of consequences we're seeing right now. And the article doesn't even mention over-fishing, pollution, or any of the other ways we're destroying our oceans. Nor does it mention how many millions of people depend on our oceans for survival. This is a matter of life or death to millions of men, women, and children.

But it does explain how slowly natural processes change. This isn't something we'll be able to undo in an instant, when we finally wake up to how much damage we're doing to our own environment.

Moreover, because processes in the ocean are slow to change this deadly water would continue to affect the Pacific northwest for another 50 years if all human CO2 emissions stopped today. It will take 30 to 50 years for the most acidic water already present along the west coast to well up. This is the beginning of a disaster that we cannot stop. The best we can do is to keep it from growing far larger and far more deadly. The changes happening in the waters of the Pacific northwest are the first stages of a global marine catastrophe if CO2 emissions are not rapidly reduced.

Obviously, all CO2 emissions aren't going to be stopped today. Or tomorrow. Or ever, probably. But whatever we do or don't do, our descendants will be living with the consequences for generations - at a minimum!