Can fertilized phytoplankton help cool the planet?

BOSTON, Sept. 8 (UPI) -- As climate change predictions have become more dire -- with the point of no return drifting closer and closer -- the possibility that global warming could be simply geo- or bioengineered away has grown more appealing.

One relatively popular concept has been the proposed use of fertilizers to boost phytoplankton blooms in the world's oceans. Like plant leaves, phytoplankton photosynthesizes sunlight, turning the solar energy into food and, in the process, converting CO2 into oxygen. Phytoplankton also gives off dimethyl sulfide (DMS), which, when absorbed into the atmosphere, forms sunlight-reflecting sulfate aerosols.

It's been suggested these cooling effects could be bolstered by fertilizing the oceans with iron sulfite and other phytoplankton-friendly nutrients. But as is often the problem with man's manipulation of the natural world, there are side effects and unintended consequences -- sometimes problematic and counteractive ones.

A new study out of MIT's Center for Global Change Science suggests higher DMS emissions could offset greenhouse gas-related warming, but also alter precipitation patterns and negatively affect water resources in vulnerable regions.

"Discussions of geoengineering are gaining ground recently, so it's important to understand any unintended consequences," Chien Wang, a research scientists at the center, said in a press release. "Our work is the first in-depth analysis of ocean fertilization that has highlighted the potential danger of impacting rainfall adversely."

Wang is the co-author of a new study analyzing the fertilization proposal, published this week in the journal Nature's Scientific Reports.

He says more research is needed to further analyze what types of impacts ocean fertilization would have on marine ecosystems.