Scientists warn of toxic Lake Erie algal bloom

June 27 (UPI) -- A toxic algal bloom is predicted for western Lake Erie this summer, which could harm the wildlife while forcing authorities to close beaches, putting a dent in local economies, the National Oceanic and Atmospheric Administration said Thursday.

Harmful algal blooms contain cyanobacteria, which are commonly known as blue-green algae, and produce a liver toxin called microcystin. So, in addition to damaging local economies, the HABs also pose a risk to human health.

"HABs also harm vital local economies by preventing people from fishing, swimming, boating and visiting the shoreline," NOAA said in a statement Thursday.

NOAA predicts this year's bloom to measure 5 on the severity index -- similar to last year's HAB, which had a severity index of 5.3. An index above 5 indicates more severe HABs, and those over 7.5 are especially severe. They form extensive scum that can cover and affect the lake and its fauna. The largest HABs occurred in 2011, with a severity index of 10, and 2015, which registered a severity index of 10.5.

The severity index is based on the amount of algal in the bloom over the last 30 days. It's also called biomass.

Experts are becoming better at predicting HABs thanks to more sophisticated satellite data and updated prediction models that have been developed over the years and as increased intensity and severity of the blooms have upped the amount of time and research invested in them. NOAA recently updated its models using data that has been gathered since 2013. Previous prediction models used older information.

"Understanding hazards such as harmful algal blooms helps us ensure the Great Lakes are a power in the Blue Economy ," said Nicole LeBoeuf, director of NOAA's National Ocean Service. "As the science behind our forecasts improves, we can give communities better information to plan for varying blooms."

The blooms will start to become visible early next month and the duration will depend on the wind conditions in September, which can't be predicted this far in advance, NOAA said. There is also a chance the blooms could change in size and severity based on changing weather conditions.

"The blooms in Lake Erie are changing. They are developing earlier over the past 10 years than previously, for reasons we do not yet understand," said Richard Stumpf, lead scientist for the seasonal Lake Erie bloom forecast. "An early start does not necessarily lead to a larger bloom, but it does mean the bloom lasts longer."

Much like meteorologists issue a short- and long-term weather forecast, NOAA will do the same for the algae bloom as it develops this summer.