SOURCE: Inside Climate News

DATE: May 15, 2018

SNIP: Blooms of harmful algae in the nation’s waters appear to be occurring much more frequently than in the past, increasing suspicions that the warming climate may be exacerbating the problem.

The Environmental Working Group (EWG) published newly collected data on Tuesday reporting nearly 300 large blooms since 2010. Last year alone, 169 were reported. While NOAA issues forecasts for harmful algal blooms in certain areas, the advocacy group called its report the first attempt to track the blooms on a nationwide scale.

The study comes as scientists have predicted proliferation of these blooms as the climate changes, and amid increasing attention by the news media and local politicians to the worst cases.

Just as troubling, these blooms could not only worsen with climate change, but also contribute significantly to greenhouse gas emissions.

[R]esearchers have found evidence that algal blooms are not just consequences of climate change, but are also sources of climate-warming emissions.

In a study released in March, researchers affiliated with the University of Minnesota, Minnesota Sea Grant and the U.S. Environmental Protection Agency found that, globally, lakes and manmade “impoundments” like reservoirs emit about one-fifth the amount of greenhouse gases emitted by the burning of fossil fuels. The majority of that atmospheric effect comes from methane, an especially potent short-lived climate pollutant.

“We found that, as the lakes go greener, more eutrophic, the atmospheric effect of the lakes skyrockets,” said John Downing, the paper’s lead researcher and director of the Minnesota Sea Grant. “That’s because plants are decomposing and shooting methane and CO2 into the atmosphere.”