A new study suggests that as oceans become more acidic, plankton could produce less of a compound that is key to cloud formation. Clouds help keep earth cool.
That possibility is raised in a new study that suggests that the activities of a tiny plankton – affected by the growing acidity of the world's oceans – could raise average global temperatures by as much as 1 degree Fahrenheit above current estimates.
"I don't think any of the previous modeling includes the effect of acidification on biological feedbacks" to the atmosphere, says Dr. Feely, who was not a member of the research team.
This "biological feedback" involves a compound produced by the plankton, called (rather unmercifully) dimethylsulfoniopropionate. Mercifully, scientists have reduced the name to the acronym: DMSP.
DMSP breaks down into forms that, once they reach the atmosphere, are readily converted into tiny aerosol particles. These aerosols, in turn, serve as the seeds for thick, low-level clouds over the ocean – clouds that are effective at reflecting sunlight back into space.
Acidification occurs as the oceans take up a significant portion of the rising levels of carbon dioxide that human activities emit. No one expects the seas to mimic battery acid. But while the changes are undetectable to anyone wading in the surf from one year to the next, they are daunting to marine organisms that have adapted to a very narrow range of pH levels, a measure of relative acidity, in seawater.