If you like fish, watch out for CO2. A Bering Sea experiment showed future oceans may have fewer fish, because future oceans may not support the productive, diatom-rich food webs that we have today.
The Bering Sea has some of the world's richest ocean food webs and most productive fisheries. Scientists are worried that this productivity may not persist in a future ocean that's warmer and has more CO2. Who cares? You should, since the Bering Sea currently provides about half of the US fish catch each year, and about 1/3 of the world's catch.
In oceanographer-speak, the future ocean experiment found diatoms (photo: above right) were replaced by nanophytoplankton, and that means low grade food for zooplankton. For the rest of us, imagine switching from Big Macs to eating alfalfa sprouts one at a time.
To make things worse, the shift may even accelerate CO2 buildup by reducing the amount of carbon that sinks into the deep ocean, slowing the "biological pump" that has kept much of our human-produced CO2 out of the atmosphere.
Will we be smart enough to mitigate and adapt in time? Or are we going to blithely run this experiment in a real ocean hope for the best?