Global river slopes

An example of the algorithm working. The black point is the low site, and the red the site upstream. The raster shows the flow accumulation in the landscape

River slope is a very useful parameter in stream geomorphology, aquatic ecology, hydrology… but hard to obtain easily at any location in the globe. This R script can obtain the stream channel just providing a pair of coordinates of a stream. The workflow is as follows:

  • Download a high resolution digital elevation model (DEM) around the site, using the package “elevatr”.
  • Model the flow accumulation in the landscape to see the stream channels.
  • Snap the coordinates provided to the closest stream.
  • An algorithm then follows the stream channel upstream for a predetermined length, and estimates the slope as the elevation difference between the site and upstream divided by the distance.
Gerard Rocher-Ros
Gerard Rocher-Ros
PhD in Ecosystem Ecology

I am interested in how ecosystems work and matter flows across different scales in the landscape.