[audio:http://wamcradio.org/EarthWise/wp-content/uploads/2012/05/EW-06-13-12-GIS-Tech.mp3|titles=EW 06-13-12 GIS Tech]
If you’ve ever used your car’s navigation system to find a nearby gas station, you’ve used a tool that is increasingly important to environmental science. Geographic Information Systems, known as GIS, are essentially three-dimensional databases.
Envision a paper map with a stack of clear plastic sheets layered on top of it. Each layer contains different information. One layer might show roads, one might show buildings, one might show vegetation, and one might record sightings of a particular animal or bird.
When the layers are stacked up, they reveal relationships that otherwise would be unseen—for instance, a tendency for a particular animal to be spotted near roads. In GIS, the layering is done by computers, which can be as small as a smartphone or as large as a mainframe, depending on the complexity of the experiment.
Environmental scientists use GIS in a variety of ways. The technology was used by the New England Aquarium to track where endangered right whales travel and to compare their trajectory to that of ships. By layering this information together, aquarium staff made recommendations that reduced ship-whale collisions.
In Baltimore, ecologists used GIS to map lead contamination in soil. The maps included layers of data about the age and placement of homes and the location of major roadways. GIS analysis revealed a strong association between these factors and the concentration of lead in soil.
This allows scientists to predict places where children might be exposed to too much lead, rather than going to the expense of massive random soil testing.
Photo, taken on August 14, 2008, courtesy of Mroach via Flickr.