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Upper Midwest Environmental Sciences Center

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UMESC Cartography and Geographic Information Systems Labs

  • The Cartography and Geographic Information Systems labs-GIS for short-make important contributions to the Center's mission. The GIS products created in the labs are used by scientists for modeling and analysis as well as by natural resource managers to improve their decision making. Let's take a closer look at the process from start to finish using land cover/land use data of the Upper Mississippi River as an example. The process begins by planning the course of an airplane with a special, gyroscopically mounted camera. The camera produces 9"x9" color infrared aerial photos that are then ground truthed to ensure accuracy. Photo interpreters take these photos, and using fine-tipped technical pens, delineate areas distinguished by similar vegetation types such floodplain forest and aquatic vegetation. At this point, the interpreted photos do not accurately reflect actual locations and distances on a map. "Georeferencing" is then done to transfer the data from the photos onto base maps with accurate latitude and longitude information. To be useful, the data has to be converted into a digital, computer-ready format. This is the role of special, wide-format scanners. Cartography and Geographic Information Systems labsThese scanners take the overlays with the classification data and convert them from a raster (dot-based) format to a vector (line and shape-based) format. To complete this stage, the data undergoes a rigorous Quality Assurance/Quality Control process.

  • Once the data become electronic, things really start to get interesting. This is the GIS lab. Here, the data is further checked and manipulated. It is then entered into a massive set of databases that contain layer upon layer of information. While we have only been collecting aerial photos for the past 15 years, we still can get a good picture of what the river landscape was like over 150 years ago. Courtesy of engineers who surveyed the river in the early 1820s, we have a collection of detailed General Land Office maps that have been digitized and entered into the Center's GIS. We can now see how the river landscape might have looked before settlement. We can also see how the building of the locks and dams in the 1930s have dramatically altered the river ecosystem. What you see here is an example of what the GIS software can do. This is an 3-D animation of Pool 8 compiled from many aerial photos. Recent examples of how GIS tools have been used include their use in radiotelemetry tracking of paddlefish and their use by the Fish and Wildlife Service to set voluntary avoidance areas around migratory bird areas on Lake Onalaska.

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