In August, OnEarth ran a shocking article by Barry Yeoman about the spread of blue-green algae that is threatening to choke the life out of Lake Erie. It's an informative and truly sobering account of how the most fertile of Great Lakes was brought back from the brink in the early 1970s, only to be threatened once again by oxygen-devoid dead zones and invasive species.
This month, NASA released new satellite photos of Lake Erie, and they reveal the startling extent of the spread of microcystis aeruginosa, or blue-green algae, which is considered to be toxic to all mammal species and can cause serious skin irritation in humans and even kill dogs.
The first image was captured on October 5 and the second on October 9. You can see how much the algae spread over the course of just four days , as relatively low winds and rainfall allowed for more growth. The second image covers much more ground -- the box on the second photo represents the borders of the first one. (Click on the photos for larger versions.)
October 5
October 9
Richard Stumpf, an oceanographer with the National Oceanic and Atmospheric Administration, called this year's infestation "the worst bloom in decades." Although the causes of the growth are complex (again, check out Yeoman's article for the nitty-gritty), it has a lot to do with the rainy spring (meaning more agricultural runoff) and the spread of invasive mussels that gobble up much of the microcystis's competitors, allowing the algae to thrive.
