High-Resolution Aerial Photography Essential to Coastal Restoration Efforts

"To us, the definition of a successful project lies in total land created or recovered," explains Bill Jones, a geographic information system (GIS) specialist at the U.S. Geological Survey's National Wetlands Research Center (NWRC) in Lafayette, La. For Jones and others at NWRC, tracking that sort of success means looking at aerial photography of project areas both before and several times after project construction. "The quality of today's high-resolution aerial photography and the use of Global Positioning System (GPS) satellite data really cuts down the time it takes to gauge our progress," he says.

Historically, photographic interpretation has been a lengthy, laborious process. “First, the photos had to be taken, then individually marked and adjusted for the curvature of the earth,” says Jones. Adjusting those photos was a time-consuming task that had to be completed by hand before map data could be entered into the computer and finally interpreted by a GIS specialist. It could take as long as three years to complete the work for all of coastal Louisiana.

Technology, however, has sped things up. “Now we can scan the photographs directly into the computer and apply GPS ground-control points to let the computer automatically rectify the photographs for the curvature of the earth,” explains Jones. Image specialists then tell the computer what to look for, such as vegetative growth or water expansion, and the machine does the interpretation automatically. According to Jones, turnaround time has dropped from years to just a few months.