With Speed and Violence Fred Pearce - Global Commons Institute

THE ACID BATH
What carbon dioxide does to the oceans
The oceans are the ultimate sink for most of the heat from the sun and also
for most of the greenhouse gases we are pouring into the atmosphere. The
atmosphere may be the place in which we live and breathe, but for long-term
planetary systems it is just a holding bay. At any one time, there is fifty times
as much carbon dioxide dissolved in ocean waters as there is in the
atmosphere. Given time, the oceans can absorb most of what we can throw
into the atmosphere. But time is what we do not have, and the oceans'
patience with our activities may be limited.
Carbon dioxide moves constantly between the oceans' surface and the
atmosphere, as the two environments share out the gas. And, because of
ever-rising concentrations in the atmosphere, the oceans currently absorb in
excess of 2 billion tons more a year than they release. Much of that surplus
eventually finds its way to the ocean floor after being absorbed by growing
marine organisms—a process often called the biological pump. Sometimes
there are so many skeletons falling to the depths that biologists call it marine
snow.
Though they are the ultimate sink for most carbon dioxide, the oceans do
not simply absorb any spare carbon dioxide left in the atmosphere. The
relationship is much more dynamic—and much less reliable. In the long run,