This season, NOAA and its research partners are predicting a smaller harmful algal bloom for western Lake Erie. The 2016 bloom is expected to measure 5.5 on the severity index, but could range anywhere between 3.0 and 7.0.
The forecast is similar to conditions last seen from 2008 to 2010, although the bloom may be as small as that seen in the relatively mild year of 2004.
The severity index is based on a bloom’s biomass–the amount of its harmful algae. An index above 5.0 indicates blooms of concern. The extreme bloom of 2011 was a 10. Last year’s was 10.5, the greatest on record.
This year’s bloom is expected to first appear in late July and increase in August in the far western basin of Lake Erie. The location and effects will depend on prevailing winds. During calm winds, some areas may experience scums that contain substantial concentrations of algal toxins.
After three years with wet springs, this spring has had more typical rainfall, leading to more normal discharge from the Maumee River. As a result there is less phosphorus entering Lake Erie and fewer nutrients to fuel a bloom.
The seasonal outlook models use nutrient load data collected by Heidelberg University’s National Center for Water Quality Research and Maumee River discharge models from NOAA’s Ohio River Forecast Center.
The models were developed by scientists at NOAA’s National Centers for Coastal Ocean Science, the University of Michigan, and LimnoTech.
Field observations on the bloom and nutrient loads are collected by NOAA’s Great Lakes Environmental Research Laboratory (GLERL) and NOAA’s Cooperative Institute for Limnology and Ecosystems Research (CILER) at the University of Michigan, Ohio State University’s Sea Grant Program and Stone Laboratory, Heidelberg University, University of Toledo, Ohio EPA, and LimnoTech and made available for monitoring and model improvements.
source: National Oceanic and Atmospheric Administration