The giant algae bloom turning the Great Lakes GREEN: Scientists warn of ‘severe’ threat from toxic bacteria

[USA] For at least fifty years, phytoplankton and algae blooms have been a regular occurrence in summer on Lake Erie.However, researchers say this year the toxic blooms could reach record levels.

The bloom is visible as swirls of green in western Lake Erie and in Lake St. Clair, and researchers warn that it is set to be ‘severe’, raising fears it could harm the health of holidaymakers and even cause problems for drinking water.

Algae washes ashore off South Bass Island State Park, Ohio in Lake Erie July 29, 2015. A algae bloom turned the water green at the park. (Eric Albrecht/The Columbus Dispatch via AP) MANDATORY CREDIT

The microscopic, floating plants generally start to flourish in June and July as the water warms and stratifies, and their numbers typically peak in August and September.

The most recent pictures were taken on July 28, 2015 by the Operational Land Imager (OLI) on Landsat 8 captured these images of algal blooms around the Great Lakes.

The bloom is visible as swirls of green in western Lake Erie (above) and in Lake St. Clair (below).

Earlier in July, NOAA scientists predicted that the 2015 season for harmful algal blooms would be severe in western Lake Erie.

Algae washes ashore off South Bass Island State Park, Ohio in Lake Erie July 29, 2015. A algae bloom turned the water green at the park. (Eric Albrecht/The Columbus Dispatch via AP) MANDATORY CREDIT

The bloom will be expected to measure 8.7 on the severity index with a range from 8.1 to potentially as high as 9.5.

This is more severe than the last year’s 6.5, and may equal or exceed 2013, which had the second worse bloom in this century.

‘This is the fourth seasonal harmful algal bloom outlook for Lake Erie that NOAA has issued,’ said Holly Bamford of NOAA.

‘NOAA’s ecological forecasting initiative, including this Lake Erie seasonal forecast, the NOAA weekly HAB bulletin, and the experimental early season HABs Tracker, provide science-based information that water managers, public health officials, and others need to make critical decisions to protect the health of their communities, understand environmental impacts, and mitigate damages to recreational activities that are a vital part of the region’s economy.’

On July 28, 2015, the Operational Land Imager (OLI) on Landsat 8 captured these images of algal blooms around the Great Lakes. The bloom is visible as swirls of green in Lake St. Clair.

The season runs through summer and peaks in September.

Blooms in this basin thrive when there is an abundance of nutrients (many from agricultural runoff) and sunlight, as well as warm water temperatures.

Harmful algal blooms can affect the safety of water for recreation, as well as for consumption (as was the case in Toledo, Ohio, and southeast Michigan during a 2014 bloom).

On July 30, 2015, drinking water was reported to be safe in these areas.

Michelle Slisher and her daughter Raina Slisher, 9, of Blacklick, Ohio walk along the shore at South Bass Island State Park in Lake Erie on July 29, 2015 despite a algae bloom that turns the water green.

The OLI image includes a special ‘coastal blue’ wavelength band that allows scientists to adjust for visual distortions caused by the atmosphere near the coast.

The dominant organism in the Lake Erie bloom is Microcystis spp., a type of freshwater blue-green algae that produces a toxin harmful to humans.

If consumed, Microcystis can cause numbness, nausea, dizziness, and vomiting and lead to liver damage, and in rare cases, it can be deadly.

Last year, on August 2, 2014, environmental monitors for Toledo and surrounding towns in northwestern Ohio determined that public water supplies had levels of microcystin toxin that were higher than recommended by the World Health Organization (1.0 parts per billion).

They warned residents not to drink or cook with tap water; boiling is not effective against the toxin.

Though the bloom has continued, treatment facilities have since added extra filtering steps (including activated carbon), and public water sources were declared safe again on August 4.

This image shows the extent of the Lake Erie algal bloom at its height in 2013 (top) and 2014 (bottom). Orange and red show concentrations that may cause scums and other issues. Different areas are affected in the two years because of wind patterns. The data came from NASA’s Aqua satellite and was analyzed by NOAA’s Center for Coastal Ocean Science.

WHAT CAUSES IT?

The dominant organism in the Lake Erie bloom is Microcystis spp., a type of freshwater blue-green algae that produces a toxin harmful to humans. 

If consumed, Microcystis can cause numbness, nausea, dizziness, and vomiting and lead to liver damage, and in rare cases, it can be deadly.

Last year, on August 2, 2014, environmental monitors for Toledo and surrounding towns in northwestern Ohio determined that public water supplies had levels of microcystin toxin that were higher than recommended by the World Health Organization (1.0 parts per billion).

They warned residents not to drink or cook with tap water; boiling is not effective against the toxin.

 

Photo: On July 28, 2015, the Operational Land Imager (OLI) on Landsat 8 captured these images of algal blooms around the Great Lakes. The bloom is visible as swirls of green in western Lake Erie (pictured). Int eh centre of the image is Pelee island, completely surrounded by the bloom.

View original article at: The giant algae bloom turning the Great Lakes GREEN: Scientists warn of ‘severe’ threat from toxic bacteria

 

 

 

 

Leave a Reply