20250321 16033800 1.0 TRUE Cyanobacteria: Presence of Blooms This data was derived as part of the Overall Assessment of the State of Nearshore Waters. Cyanobacteria, a blue-green algae, occurs naturally in freshwater but an overgrowth can result in a harmful algae bloom that can release toxins dangerous to human and ecosystem health. Cyanobacteria is assessed by calculating the extent of cyanobacteria blooms detected within a Regional Unit, using satellite composites. An additional flag is assigned to Regional Units where cyanobacteria is a source of high stress, as it is considered a serious concern. Thresholds for severity are based on World Health Organization guidelines.Satellite composites are from the National Oceanic & Atmospheric Association (NOAA) Harmful Algal Bloom Monitoring program.LAKE ERIE: 10-day composite images from the MODIS satellite, with Cyanobacteria Index algorithm applied; June - October, 2012-2017LAKE ONTARIO: 10-day composite images from the MODIS satellite, with Cyanobacteria Index algorithm applied; June - October, 2016-2018LAKE SUPERIOR: 7-day composite images from the Sentinel 3Asatellite, with Cyanobacteria Index algorithm applied; June - October, 2019Points represent the Regional Unit centroid.Low Stress: no bloom; High Stress: bloom Environment and Climate Change Canada - Strategic Policy Branch - RDGO; National Oceanic & Atmospheric Association (NOAA) Harmful Algal Bloom Monitoring program