Worsening Algae Blooms Could Significantly Increase Global Methane Emissions

Worsening Algae Blooms Could Significantly Increase Global Methane Emissions

SOURCE: Yale e360 DATE: March 27, 2019 SNIP: Population growth and climate change over the next century will lead to a major rise in the number and severity of algae blooms in the world’s lakes, increasing global methane emissions by 30 to 90 percent, according to a new study led by the U.S. Environmental Protection Agency. The study, published in the journal Nature Communications, examined the impacts of global population growth (an estimated 50 percent by 2100), climate change-induced flooding and runoff, and rising global temperatures on nutrient levels in the world’s lakes. It found that the extra sewage, fertilizers, and other nutrients entering waterways will increase the eutrophication of the world’s lakes by as much as 200 percent by 2050, then double or quadruple by 2100. Eutrophication — or excess nutrient levels — causes dense algae blooms to form, which can ruin drinking water supplies and create hypoxic “dead zones” that suffocate marine life. These algae blooms are also a major source of global methane emissions — a greenhouse gas 34 times more potent than carbon dioxide in the short...
Mysterious Microbes Turning Polar Ice Pink, Speeding Up Melt

Mysterious Microbes Turning Polar Ice Pink, Speeding Up Melt

SOURCE: National Geographic DATE: September 14, 2018 SNIP: A surprisingly happy and healthy ecosystem of algae is not only turning parts of the Greenland ice sheet pinkish-red, it’s contributing more than a little to the melting of one of the biggest frozen bodies of water in the world. The discolored snow isn’t just an Arctic phenomenon. “It’s actually a global occurrence,” says Alexandre Anesio, a biogeochemist from the University of Bristol. “In order for them to form visible blooms and increase the melting of the snow and ice, they just need the right conditions, which at a minimum involve basic nutrients and melting,” says Anesio. “As the climate gets warmer, the availability of liquid water from snow and ice becomes higher, favoring the growth of snow and ice algae.” “I think that this is increasingly becoming a problem in Arctic, Alpine, and Himalayan glaciers,” Anesio says. Blooms of red snow and brown ice are turning up in Antarctica, too. And experts are not accounting for the effect in their projections of global sea level rise, despite increasing evidence of what darkening snow is doing to the world’s glaciers. The darker surface [from the algae growth] lowers the “albedo,” or the ability of the ice to reflect the sunlight back into space, and that results in more light absorbed and more melting. As algae spreads over larger areas of the ice sheet, the effect will be compounded, leading to even more melting. A recent study found that algal blooms can contribute as much as 13 percent more ice melt over a season. So far, the blooms have not been taken...
Florida declares a state of emergency as red tide kills animals and disrupts tourism

Florida declares a state of emergency as red tide kills animals and disrupts tourism

SOURCE: Washington Post and DeSmogBlog DATE: August 14, 2018 SNIP: Florida’s governor this week made official what residents of southwest Florida already knew: The bloom of toxic algae that has darkened gulf waters is an emergency. The red tide has made breathing difficult for locals, scared away tourists, and strewn popular beaches with the stinking carcasses of fish, eels, porpoises, turtles, manatees and one 26-foot whale shark. Gov. Rick Scott (R) late Monday declared a state of emergency in seven counties stretching from Tampa Bay south to the fringe of the Everglades. Scott promised $1.5 million in emergency funding. Citizens in retirement communities are reporting respiratory distress from the vapors of the microscopic red-tide organism called Karenia brevis. A recent study found a 50 percent spike in hospital visits due to respiratory problems during red-tide blooms. Rick Bartleson, a research scientist with the Sanibel-Captiva Conservation Foundation, said water samples offshore show lethally high concentrations of algae. “There’s no fish left. Red tide killed them all,” he said. “All of our concentrations of red tide are still high and would still kill fish if they were out there.” [T]he incidences of red tides seem to have increased since the 1950s and 1960s. Climate change could be a factor; warmer waters, up to a certain point, are congenial to algal growth. The Gulf of Mexico’s surface temperature has warmed by about two degrees Fahrenheit since 1977. There’s a more direct human handprint on the current crisis: Florida’s landscape and the flow of water have been radically altered by agriculture, canals, ditches, dikes, levees and the sprawling housing developments that have sprouted...
Toxic Algae Blooms Occurring More Often, May Be Caught in Climate Change Feedback Loop

Toxic Algae Blooms Occurring More Often, May Be Caught in Climate Change Feedback Loop

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...
Sea ice algae blooms in the dark

Sea ice algae blooms in the dark

SOURCE: AAAS EurekAlert DATE: February 6, 2018 SNIP: Researchers from Aarhus University have measured a new world record: Small ice algae on the underside of the Arctic sea ice live and grow at a light level corresponding to only 0.02% of the light at the surface of the ice. Algae are the primary component of the Arctic food web and produce food far earlier in the year than previously thought. The general view has been that ice algae do not obtain sufficient light for growth when they are covered by a more than 30-50 cm deep cover of snow and ice. The new measurements completely change that view and show that ice algae may play an important role much earlier in the spring in the Arctic than hitherto assumed. Temperatures are rising in the Arctic. When the snow on top of the ice gets warmer, the algae residing on the underside of the ice receive more light. This may significantly impact the growth of the algae and the extent of the ‘spring bloom’. This new knowledge must be considered in the puzzle of how the Arctic will respond to a warmer...