Riverine flooding in the terrestrial environment can be monitored and predicted from the space environment, according to researchers from the University of Glasgow, U.K.

The forecasting approach relies on high-resolution large-scale particle image velocimetry video sensors placed aboard commercial satellites to track the dynamics of river flow and floods. Optical flow measurement algorithms have been applied to estimate velocity by monitoring the movement of visible features between frames. Analysis of such video footage could replace or enhance the way governments rivers are monitored, particularly in remote areas lacking stream gauges, and improve the ways that floods are predicted.

The method described in Geophysical Research Letters was developed using video footage from a Chinese satellite to measure the discharge of a February 2022 flood along a 12-mile section of the Darling River in Tilpa, Australia. Analysis of the movement of visible surface features between frames in the video footage enables estimation of the speed of water flow. When combined with detailed elevation maps of the flooded region, these estimates can pinpoint flow discharge to within 15% of data documented by stream gauges on the river during the flood.