UW-Madison researchers have teamed up to help complete the first satellite-based inventory of the clarity of Wisconsin's lakes.
Three years ago, work began on an innovative new method of assessing the water quality of Wisconsin's lakes from the distant depths of space. The efforts have recently come to fruition in the form of a satellite soaring 438 miles overhead that compiles detailed lake images and immediately conveys the information back to Earth for analysis.
\The vast majority of the state's lakes are not monitored routinely,"" said Thomas Lillesand, director of UW-Madison's Environmental Remote Sensing Center and coordinator of the NASA-funded project. ""Our research aims to utilize ground-based sampling by calibrating digital satellite images with the ground data, and then using the satellite images to predict the clarity of lakes that have not yet been sampled on the ground.""
The project is part of a large, NASA-funded research project called the Satellite Lake Observatory Initiative, and required help from a wide range of groups and organizations from across the state. The UW-Madison Center for Limnology, the Wisconsin Department of Natural Resources, Green Bay Metropolitan Sewerage District and hundreds of citizen volunteers all joined forces to provide the water-quality data necessary to calibrate the satellite equipment.
While the new satellite-based method will never completely replace conventional water-sampling techniques, Lillesand is enthusiastic about its effectiveness.
""[The new method] is as accurate, more efficient and permits us to take a look at the 'big picture' of lake-water clarity statewide,"" Lillesand said. ""This should help us develop and evaluate lake-management activities, and [separate] natural variability in lake clarity from possible responses due to changing land use and climate.""
""In the future we hope to apply [this] data to the largest lakes in the state on a daily basis and extend our analysis into the Great Lakes,"" Lillesand said.
Researchers at Michigan State University are also working alongside UW-Madison and University of Minnesota teams to expand the coverage of this new approach to the three-state area.
""The collaboration between our two universities and Michigan State University with our regional NASA project has been very positive,"" said Marvin Bauer, professor of remote sensing at the University of Minnesota. ""While we are not the first researchers to use satellite data to classify lake clarity, our three universities are the first to apply the technology over such a large geographic area and to such a large number of lakes.""
Bauer recently completed a similar counterpart to Lillesand's work. Bauer is excited about the possibilities and said the new method will be much more cost-efficient.
""This is the most significant and successful application of satellite remote sensing that I have been associated with in the 30 years I have been working with Landsat data,"" Bauer said. ""We can economically acquire information on all lakes instead of a small fraction--the cost of the satellite method should be less than $100,000 per year for an entire state.""
Lillesand is quick to applaud all those who had a hand in making the project a success.
""This has been a real demonstration of progress through partnership, from NASA, to our colleagues on campus, the DNR and other cooperators,"" Lillesand said. ""And we could not have done any of this without the invaluable help of the citizen volunteers who sample their lakes as the satellite comes overhead.""
""[Lakes] are central to our heritage, economy and environmental future,"" Lillesand said. ""The citizens of Wisconsin care about their lakes.\
