South Dakota State University's Geographic Information Science Center of Excellence (SD, USA) has released research data gathered through innovative satellite mapping and sampling that provides precise estimates of tropical forest clearing.

The original sampling technique was developed by a group of researchers at the GIScCE. Although the approach is novel, it builds upon past research history of land cover monitoring and sampling. The new method uses one type of remote sensing data to objectively stratify land surfaces for sampling and a second variety to analyze the samples for estimating forest cover and change over time.

Collected information comes from low-and-high spatial resolution satellite datasets, measuring where and how quickly tropical rainforests disappear. The method enables marking the quantity of forest cover and change across the tropics.

This new approach suggests that more than 27 million hectares of forest area were cleared between 2000 and 2005.

The new sampling technique shows where and how widely spread the forest loss has become. Researchers say the technique is important because it can repeatedly measure large regions efficiently and supply a consistent measure to estimate global trends in forest loss and gain.

The new method was developed at South Dakota State University in collaboration with researchers at the United States Geological Survey's National Center for Earth Resources Observation and Science (EROS), the State University of New York's College of Environmental Science and Forestry and the University of Maryland.

The GIScCE uses remote sensing, geographic information systems, digital mapping and geostatistics to document and understand the changing earth. The Geographic Information Science Center of Excellence is a partnership between SDSU and EROS and provides SDSU faculty and students and EROS scientists the opportunity to collaborate on earth observation research.