Remote sensing resources
The capabilities for the remote sensing of water quality at the Wisconsin DNR are tied to the availability of Landsat 7 ETM+ and Landsat 8 data through the NASA/USGS Landsat Program. This data is used for the operational satellite retrieval of water clarity from thousands of lakes in Wisconsin and contributes to the assessment of the trophic state of these lakes.
The Landsat program
The NASA/USGS Landsat Program started when the Earth Resources Technology Satellite 1 (ERTS 1) was launched in 1972. This satellite was later renamed to Landsat 1 and followed by seven more satellites. Landsat 8 is the latest member of the series and was launched in 2013. The Operational Land Imager (OLI) onboard Landsat 8 has nine multispectral bands with a spatial resolution of 30 m and one panchromatic band with a spatial resolution of 15 m. The Thermal Infrared Sensor (TIRS) has two bands with a spatial resolution of 100 m. The multispectral bands are used in the satellite retrieval of water clarity while the panchromatic band might provide important information for the remote sensing of aquatic vegetation. The thermal bands have the potential to advance the remote sensing of water temperature in future remote sensing activities at the DNR.
Satellite data from the Landsat Archive of the USGS EROS Center is downloadable at no cost through the
USGS EarthExplorer [exit DNR],
Global Visualization Viewer (GloVis) [exit DNR], and
LandsatLook Viewer [exit DNR].
The LandsatLook Viewer might provide the easiest access to the satellite data. Click “Start The LandsatLook Viewer”
on the “Welcome to the LandsatLook Viewer!” page and select the satellite(s) you are interested in. Type the name of
your county, for example “Vilas County, WI”, into the search field to see an overview of your area and use the sliders
to specify the dates and maximum cloud cover for the images you are interested in. Click “Show Images” and use the time
slider to look through the search results. Click “Metadata and Data Access” if you would like to add images to your chart
and “Go to Chart” to download the images. “Get LandsatLook Image” leads you to a preview image you can look at on your
computer and “Get Landsat Data” leads you to the actual Landsat data.
The NASA Landsat Science [exit DNR] and USGS Landsat [exit DNR] websites provide excellent resources for detailed information related to the NASA/USGS Landsat Program.
Palmer, S.C.J., Kutser, T., and Hunter, P. (2015) Remote sensing of inland waters: Challenges, progress and future directions. Remote Sensing of Environment, 157, 1-8
Kutser, T., Verpoorter, C., Paavel, B., Tranvik, L.J. (2015) Estimating lake carbon fractions from remote sensing data, Remote Sensing of Environment, 157, 138-146
Brezonik, P.L., Olmanson, L.G., Finlay, J.C., and Bauer, M. (2015) Factors affecting the measurement of CDOM by remote sensing of optically complex inland waters. Remote Sensing of Environment, 157, 199-215
Kutser, T. (2012) The possibility of using the Landsat image archive for monitoring long time trends in coloured dissolved organic matter concentration in lake waters. Remote Sensing of Environment, 123, 334-338