On September 17 President Obama's recently established Ocean Policy Task Force issued its first report suggesting areas where federal action on our public seas can and should be improved. Some of the areas like coastal pollution and industrial overfishing are familiar while others, such as ocean acidification, are threats that have only now begun to emerge
More than 40 years after Woodstock it's the ocean that's on a bad acid trip. It's been scraped raw, emptied out, overheated, poisoned and abused, not a good time to be ingesting dangerous chemicals. Normally carbon dioxide isn't considered a dangerous chemical compound to the sea or to us, but rather a natural part of the chemistry of life. At 225 parts per million in the atmosphere this greenhouse gas, along with methane and water vapor, has created an exceptionally stable and temperate climate over the past 10,000 years a period that has also seen, not coincidentally, the rise of modern civilization. But since the industrial revolution over 150 years ago humans have been adding carbon dioxide to the atmosphere through the burning of fossil fuels like coal, oil and natural gas along with the burning and logging of forest lands that also adds to the carbon load.
Today carbon dioxide has grown from a pre-industrial 225 to 385 parts per million in the atmosphere and still climbing at .5 percent a year, a rate of change 100 times faster than at any time over the past 650,000 years. A doubling of pre-industrial CO2 almost every rreputable climate scientist now warns will have catastrophic consequences for the present mix of life on the planet. Some (inspired by author/activist Bill McKibben) are advocating a concerted campaign to actually try and roll back atmospheric carbon dioxide to 350 parts per million though that would require the kind of technological innovation and societal mobilization that hasn't been seem since World War Two. Unfortunately we're still treating the climate crisis like the invasion of Grenada.
At the turn of the 21st century climatologists were having problems with their computer models even in the wake of the hottest years and decades in recorded history. Given the increased emissions of industrial carbon dioxide it appeared the atmosphere should be heating up even more rapidly than it was. Then around 2003 and 2004 testing confirmed that about 30 percent of human generated C02 was being absorbed by the ocean, computer glitch solved.
The only problem is when carbon dioxide dissolves in seawater it forms carbonic acid increasing the acidity of seawater and decreasing the ability of shell forming critters including various forms of algae, plankton, corals, oysters, clams, sea urchins and sea stars to pull calcium carbonate out of the water to build their homes and skeletal structures. Some have called this the osteoporosis of the sea. Since cold water can also holds more CO2 than tropical seas the consequences are becoming more evident in the polar regions where migratory Gray Whales spend their summers furrowing the muddy bottom of the arctic sea feeding on tiny shelled marine anthropods while walruses feast on nearby clam beds. Reduced calcium carbonate will likely mean less whale and walrus chow just as melting ice means less polar bear and ringed seal habitat.
So little is known about what's going on with ocean acidification however (and research funding is still so limited) that scientists can't agree if the ocean is now so saturated with anthropogenic carbon that it can't absorb much more and the atmosphere will soon start heating up even quicker than it already has or if the acidification and ocean warming will continue so that by the end of the century it will look more like it did millions of years ago - an ocean full of jellies and bacterial mats with fewer bony fish, shellfish, corals and mammals. That's what my friend Dr. Jeremy Jackson of Scripps Institution of Oceanography calls the rise of the slime and that's why some people look at the state of the seas and essentially give up. Me, I figure we can't know if it's really too late to turn the tide or not. All we can be certain of is if we don't try we lose.