A pressing question for water scientists: just how small can a lake be and still reveal its secrets from space? But here’s where it gets interesting. Volunteers are showing that even tiny lakes aren’t out of reach for satellite measurements, and that the small details can matter as much as the big ones.
Volunteers in the Lake Observations by Citizen Scientists and Satellites (LOCSS) program have been gathering lake water level data since 2017. Now, that same body of data is being used to test how accurately water levels on lakes can be measured from orbit. The study, published in GIScience & Remote Sensing, demonstrates that modern satellites equipped with nadir altimeters can track water level changes with fairly high precision even for lakes smaller than one square kilometer. These measurements are invaluable for scientific research and for managing natural resources.
One LOCSS participant, Nelsi Durán from Ciénaga La Musanda in Colombia, described the shift in perspective:
“We can look at the wetland now with different eyes.”
Beyond validating measurements, the LOCSS effort also highlights where satellite methods can stumble. Water level variability emerges as a key factor: small lakes that experience rapid level changes can be measured reliably from space, while lakes with little fluctuation tend to yield less accurate data.
To date, LOCSS has involved 274 lakes across 10 countries—the United States, Canada, Colombia, Chile, Kenya, Spain, France, India, Pakistan, and Bangladesh. Since its inception, more than 10,000 citizen scientists have contributed water level observations to the project.
Ecologist Dan Grigas of the Forest Preserve District in DuPage County, Illinois, explains why this matters: “We chose to work with LOCSS because widening our understanding of how environments change over time is important.” He adds that studying both near-term and long-term climate shifts helps illuminate freshwater ecology. He also notes that citizen scientists strengthen ties among government agencies, local communities, and the ecosystems we all value.
If you’re curious about Earth, water resources, and how everyday volunteers can contribute to science, visit locss.org and look for a lake near you.
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Last Updated
Dec 16, 2025
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