Giant Toxic Algae Bloom Again Plagues Lake Erie

Late summer will see a return of cyanobacteria, the toxic, oxygen-depleting blue-green slime that has been plaguing Lake Erie in recent years, according to NOAA scientists. Continue reading →

It turns out that NBA superstar LeBron James isn't the only one returning to the Midwest.

Late summer will see a return of cyanobacteria, the toxic, oxygen-depleting blue-green slime that has been plaguing Lake Erie in recent years, according to NOAA scientists. This year's bloom isn't expected to be quite as bad as last year's intense algae or the record-setting bloom in 2011, which covered 1,930 square miles of water. But it's still probably going to cover a large stretch of the lake's western portion, according to NOAA scientists.

NEWS: Why Lake Erie is Under Attack from Algae Blooms

Cyanobacteria is a pretty color in satellite photos, but it's a major public health and environmental hazard that can make people and pets sick and kill fish and aquatic plants.

Algae blooms are a natural part of the life cycle of an aging lake, according to the U.S. Environmental Protection Agency, but their intensity is being exacerbated by phosphorus runoff from agriculture, lawn care and other human activity. About 80 percent of the land in the Great Lakes watershed is used for farming, and much of it drains into the shallowest portion of Lake Erie, according to this PLOS ONE article on the blooms.

Lake Erie's summer blooms tend to be a particular type of cyanobacterium called Microcystis. The latter is a greenish, thick, paint-like, sometime grainy material that accumulates along the lake shore. As this EPA primer notes, dried Microcystis scum - wow, even typing that makes us wrinkle our noses in disgust - may contain high concentrations of bacteria for several months. That allows toxins to dissolve in the water even when the cells are no longer alive or after a recently collapsed bloom.

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Such blooms are a big problem in waters in other parts of the United States and the world as well. In 2013, the Chinese seacoast off the city of Qingdao was plagued by a giant bloom of an algae called Enteromorpha prolifera, which turned waters green and required the use of bulldozers to remove more than 7,300 tons of scum from beaches. Fortunately, at least, that algae wasn't toxic, but it did suck oxygen from the water and block sunlight, killing local marine life.

Photo: This summer's toxic algae bloom in Lake Erie won't be quite as bad as the one from 2011, pictured above. But it still is a major environmental problem. Credit: NOAA

Although 75% of the planet is a relatively unchanging ocean of blue, the remaining 25% of Earth's surface is a dynamic green. This still image is a snapshot of the Earth created from a year’s worth of data from April 2012 to April 2013 taken from the NASA/NOAA Suomi NPP satellite.

Subtle vegetation changes are visible in this year-long visualization. Large-scale patterns vary with seasons, but the local variations in green are also sensitive to precipitation, drought, and fire.

The "river of grass" extending south of Lake Okeechobee shows clear signs of its modified state with areas of dense agriculture, urban sprawl and water conservation areas delineated by a series of waterways that crisscross Southern Florida.

The Mississippi and its many tributaries empty into the Gulf of Mexico - and where these two bodies of water meet lies 40% of the salt marsh in the contiguous United States.

Farmland straddles the Platte River in Nebraska. This region produces around 40% of the annual corn yield for the U.S. and nutrient input from this region drives aquatic and marine ecosystems from the Mississippi watershed to the Gulf of Mexico.

The Rocky, Cascade, and Coast Mountain Ranges dominate the landscape of the Pacific Northwest. Potato and other agriculture can be seen in the bottom center of the image as the Rockies give way to the plains of Idaho.

Amidst the deserts of Egypt, the Nile River provides life-sustaining water to the region. Also visible are the urbanized areas of northern Egypt.

Moisture from the Caspian Sea precipitates on the northern edge of the Elburz Mountains, and on the southern edge, deserts emerge in the rain shadow.

The Tigris (north) and Euphrates (south) Rivers create a fertile crescent through central Iraq.

Dense boreal forest in Central Russia near the town of Langepas, on June 18-24, 2012, before a massive fire.

July 23-29, 2012 -- While the surrounding area became more green, irregularly shaped areas of lesser vegetation are the burn scars left by massive wildfires near the Russian town of Langepas.