Filaments of green scum swirl across the surface of Guatemala’s Lake Atitlán in this photo-like image taken by NASA’s EO-1 satellite on November 27, 2009.
Microcystis blooms have become a regular occurrence on the lake. In 2014, the bloom was especially intense around the water intake for Toledo, Ohio, causing managers to warn residents not to consume public drinking water for several days.
A large bloom of cyanobacteria, more commonly known as blue-green algae, spread across Guatemala’s Lake Atitlán in green filaments and strands that are clearly visible in this simulated-natural-color image from November 22, 2009.
Lake Erie’s shallowness not only makes it more prone to fluctuating water levels, but also enables this lake to freeze and thaw more readily than its neighbors.
The Great Salt Lake of northern Utah is a remnant of glacial Lake Bonneville that extended over much of present-day western Utah and into the neighboring states of Nevada and Idaho approximately 32,000 to 14,000 years ago. The north arm of the lake, displayed in this astronaut photograph from April 30, 2007, typically has twice the salinity of the rest of the lake due to impoundment of water by a railroad causeway that crosses the lake from east to west. The causeway restricts water flow, and the separation has led to a striking division in the types of algae and bacteria found in the north and south arms of the lake.
At an average elevation of 3,812 meters (12,507 feet), Lake Titicaca is one of the highest lakes in the world. The lake is positioned between two major ranges of the Andes Mountain chain and has very limited drainage. The limited outflow of the lake allows for the accumulation of nutrients derived primarily from surrounding communities’ agricultural and sewage waste. The increased nutrient levels can lead to plankton blooms. This astronaut photograph, taken from the International Space Station, captures two such blooms along the eastern shoreline of the lake.