- Detecting thin layers of algae is not a trivial remote sensing problem.
- The Earth Systems Research Lab recently identified an algal bloom using LiDAR.
- This was the first time that this had been accomplished.
I worked on a project a few years ago where we were attempting to use multispectral imaging to remotely sense the presence and dynamics of algal blooms in a river in Georgia. The suspected polluter was a large pig farm, but it turned out to be very difficult to prove it. Being able to detect a thin layer of algae is not a trivial remote sensing problem. These layers can affect the use of underwater acoustics and optics. Stratification is also important in the study of climate change.
This spring, the Earth Systems Research Lab’s Jim Churnside and his colleagues took an unprecedented look at the progression of a phytoplankton bloom in Washington’s East Sound, by flying a remotely-controlled lidar on a small Cessna airplane over the water. Backed by ship and underwater glider data from Percy Donaghay, Jan Rines, and Jim Sullivan of the University of Rhode Island, the study provided the first on-the-ground validation that airborne lidar can detect thin layers of phytoplankton in water.
The LiDAR was able to monitor the dynamics of the bloom over time, including its vertical movement. This is certainly going to open up new uses for the technology.