Rivers and streams cover more of the Earth than previously thought and therefore play a greater role in controlling concentrations of greenhouse gases in the atmosphere, according to a new study.
Using satellite images from NASA, the team developed the Global River Widths from Landsat (GRWL) Database, the most comprehensive global map of river length and width.
“We were able to measure over two million kilometers of rivers that were wider than 30 meters,” says George Allen, an assistant professor of geography in the College of Geosciences at Texas A&M University.
For the rivers that were too narrow to accurately measure from the satellite images, the researchers applied a novel statistical technique that utilized the fractal characteristics of river networks. “There are many more narrow rivers than wide rivers, and we found that the relationship between river length and width is actually pretty predictable,” Allen says.
“We added up all the rivers and streams around the world [and] got an area larger than the size of Texas. The estimate was significantly larger than the previous best estimate, particularly […]