Below-average harmful algal bloom predicted for western Lake Erie

University of Michigan researchers and their partners are forecasting that western Lake Erie will experience a smaller than average harmful algal bloom this summer, which would make it less severe than 2021 and more akin to what was seen in the lake in 2020. This year's bloom is expected to measure 3.5, with a potential range of 2-4 on the severity index-whereas last year's bloom was measured at a 6, according to the annual forecast released today by the National Oceanic and Atmospheric Administration, which funds the research. The index is based on the bloom's biomass-the amount of algae-during the peak 30 days of the bloom. An index above 5 indicates more severe blooms. Blooms over 7 are particularly severe, with extensive scum formation and coverage affecting the lake. The largest blooms occurred in 2011, with a severity index of 10, and 2015, with a severity index of 10.5. "While this year's forecast is similar to the long-term average, the long-term average is not the goal.