Field Monitoring (Lake Erie)

Produced in Collaboration with NOAA GLERL

How to Read the Data

Sampling Date

Field monitoring for HABs occurs on a weekly basis in Lake Erie during HAB season (July – October). The sampling date indicates the most recent monitoring date. 

Monitoring Stations

Weekly samples are taken at two different depths at each monitoring station: a surface sample (0.75 m from surface), and a bottom sample (1 m from bottom). The total depth at each station is listed in parentheses in the location search bar. 

Data Type

Temperature: Temperature of water sample in degrees Celsius 

Turbidity: a measurement of how easily light passes through water. The cloudier the water, the greater the turbidity. Turbidity can be caused by algae, sediments, or solid wastes.

Extracted chlorophyll a: chlorophyll is a pigment that allows algae (and all plants) to convert sunlight to energy via photosynthesis. The amount of chlorophyll in the water is used as an indicator for the total amount of algae present. Samples are taken back to the lab and the pigments are extracted from the algal cells for measurement.

Extracted phycocyanin: phycocyanin is a pigment found in cyanobacteria, the group of organisms responsible for toxin-producing HABs. Levels of phycocyanin that are higher than chlorophyll a indicate heavy populations of cyanobacteria. Samples are taken back to the lab and the pigments are extracted from the algal cells for measurement.

Particulate microcystin: a measurement of the amount of toxins found within cells of Microcystis, the predominant cyanobacteria found in Lake Erie  

Dissolved microcystin: a measurement of the amount of toxins that have been released from cells of Microcystis and dissolved in the water

Data Points

Each point on the graphs below represents a water sample. When hovering your cursor over a data point, the sample date and precise data measurement can be found in blue text at the bottom of each graph. Red half circles indicate that microcystin or phycocyanin measurements were for that sample were below detectable levels (<0.1ug/L for microcystin)

Data Source

This data is produced by the Western Lake Erie Harmful Algal Bloom monitoring program, a joint effort by NOAA Great Lakes Environmental Research Lab (GLERL) and CIGLR with support from the Great Lakes Restoration Initiative. Monitoring data is provided “as is” and have not yet been subjected to quality control or quality assurance procedures. For data with QAQC, please refer to annual seasonal reports. We work hard to post data from each week’s monitoring soon after collection, but there may be delays.

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About the Research

Visit NOAA GLERL’s website for a deeper look into our HAB research. CIGLR supports the mission and goals of the NOAA Great Lakes Environmental Research Lab, and collaborates with them to develop these next-generation NOAA forecasts. Read the disclaimer.

Learn More

Explore other resources on Lake Erie harmful algal blooms.

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Field Monitoring Lead
Casey Godwin
(734) 741-2235

Stakeholder Engagement
Devin Gill
(734) 741-2283

Media Contact
Mary Ogdahl
(734) 741-2276