is editor, News and Humanities, at CMAJ
Is Sea Sick a one-woman play or a live TED-esque talk? Hard to know, but harder still to care about applying labels to the medium when the message is so powerful: the ocean’s chemistry is changing with climate change. “It’s warm, breathless and sour,” says , a long-time reporter with The Globe and Mail, turned freelance. And when the ocean dies, so do we.
Mitchell’s international best-seller, (2009; McClelland & Stewart), is now hitting the stage in what is billed as a ‘one-woman nonfiction play’, but is more like an animated lecture, replete with blackboard, albeit with a few theatrical-effects. No matter. If she reaches a new audience, so much the better, and last night she reached a couple of CMAJ editors at Ottawa’s .
In a sea-shell, her extensive investigation — 3 years and 13 trips worldwide — led to one conclusion: carbon dioxide levels are changing in the pH of the world’s oceans, and it’s dire. When carbon dioxide dissolves in water the result is carbonic acid.
In 1750, when humans started burning fossil fuels in earnest, carbon dioxide levels in the atmosphere were 280 parts per million (ppm); pH 8.20. Today, those levels stand a 400 ppm and pH 8.05. By 2050, scientists project they will stand at 560 and 7.80 (if we carry on at our current rate of churning out carbon dioxide. We might think that an absolute drop in pH of 0.15 is too small to merit our concern. But anyone familiar with how pH works - on a logarithmic and not a linear scale - will understand that the ocean is 30% more acidic now than it was a generation ago. And if we consider that human blood pH must be tightly regulated between 7.35 and 7.40 to be compatible with normal function we can perhaps begin to understand how serious it is that our oceans have become a little bit more acidic. It’s planetary acidosis.
“The ocean is the breath of life for everything,” said Mitchell. Ninety-nine percent of life on earth is in the ocean. “If everything on land died, life in the ocean would be okay. If the ocean dies, everything dies.”
What’s happening already is that warm-water organisms are migrating into formerly cooler areas. Mediterranean sea life is now found off the coast of Plymouth, UK. And the increased acidity will cause shells, comprised mainly of calcium carbonate, to dissolve. In a dramatic on-stage demonstration of this process, Mitchell dropped a piece of chalk into a clear pitcher of vinegar: fizzing and white foam, then nothing. The chalk disappeared.
There have been five mass extinctions through the history of the world, says Mitchell; the last was 65 million years ago when the dinosaurs perished. All five had the same underlying cause: increased carbon dioxide, relatively suddenly released into the atmosphere. Mitchell reports that she’s spoken to expert scientists who think we are heading in the same direction as the chalk in her demo. We are bringing about the next mass extinction.
The first scientific paper on ocean acidification and deoxygenation was published in 1999; the scientific community is still getting on top of the science and it hasn’t really hit the public radar yet, says Mitchell. Her work, including , spreads the word.
And to those persistent climate change nay-sayers, Mitchell has this to say: “They are talking about a belief system not susceptible to logic or fact.” She likened them to those who opposed Charles Darwin’s theory of evolution. “It’s very hard to change people’s cosmology.”
“We don’t understand the ocean for its biological heft,” Mitchell told her Ottawa audience May 9. Ocean acidification cannot be quickly reversed, but we can “stop or reduce the carbon dioxide so it doesn’t speed up and get worse.”