A comparison of Satellite Derived Versus In-Situ Chlorophyll Values on Two Manitoba Great Lakes

Thumbnail Image
Herbert, Claire
McCullough, Greg
Kling, H.J.
Barber, David
Journal Title
Journal ISSN
Volume Title
The waters of Lakes Winnipegosis and Manitoba are Case II waters, meaning their optical properties are influenced not only by phytoplankton (chlorophyll-a) but also by total suspended sediments (TSS) and coloured dissolved organic matter (CDOM). Large areas in these lakes are very shallow, so that either bottom reflectance (depths vary from 2 - 9 meters) or submersed vegetation add more complexity, making it difficult to monitor chlorophyll-a and TSS with both precision and accuracy. In other large lakes in the Canadian prairies (e.g. Lake Winnipeg and Lake of the Woods), local calibration using in situ data has been useful for retrieval of these parameters In the open water seasons in 2016 to 2017, surface and bottom water quality samples were taken at 43 stations throughout Lakes Manitoba, Winnipegosis and Waterhen. Sites were sampled three times per year (spring, summer and fall) to capture a variety of open water conditions. At selected sites, a field spectrometer (ASD fieldSpec Pro) was used to measure surface reflectance over the spectral range used by ocean colour satellites.
sentinel-3, satellite, remote sensing, algae, chlorophyll, Lake Manitoba, Lake WInnipegosis, freshwater