Volunteers help NASA measure water from space, even tiny lakes

For the past seven years, ordinary people have been wading into lakes with measuring tools, collecting data that's now reshaping how scientists monitor Earth's water from orbit. The Lake Observations by Citizen Scientists and Satellites (LOCSS) project has quietly proven something counterintuitive: satellites can track water levels in lakes smaller than a square kilometer — places so small they'd barely show up on most maps.

The findings, published in GIScience Remote Sensing, came from comparing ground measurements taken by over 10,000 volunteers with data from space-based instruments called nadir altimeters. Across 274 lakes in 10 countries — from Colombia to Bangladesh, Illinois to Kenya — the pattern was clear. Modern satellites can capture water level changes with surprising precision, even in places where you'd think the view from space would be too blurry to matter.

But the project also revealed something unexpected. The accuracy isn't just about size. It depends on how much the water level actually moves. Lakes where water levels fluctuate significantly — swelling with rain, shrinking in drought — show up clearly on satellite data. Lakes that stay stubbornly stable are harder to read from space, their subtle changes lost in the noise.

Nelsi Durán, a volunteer from Ciénaga La Musanda in Colombia, described the shift in perspective: "We can look at the wetland now with different eyes." That's the real breakthrough. For communities managing water resources, tracking wetland health, or trying to understand how climate patterns are reshaping their local environment, this work means something concrete. A farmer in Pakistan or a conservation officer in Kenya can now cross-reference satellite data with ground truth, building a more complete picture of how their water is changing.

Dan Grigas, an ecologist with the Forest Preserve District in Illinois, explained why his team joined the effort: "This program allows for and relies on citizen scientists to participate, which strengthens the relationships among government agencies, the people they serve, and the environments that we all treasure." That's not just feel-good language. It's a recognition that the best environmental monitoring happens when satellites and smartphones, institutions and local knowledge, work together.

The LOCSS project is still recruiting. If there's a lake near you, you can join the thousands already feeding data into this growing picture of how Earth's freshwater is shifting — one measurement at a time.

Get Involved

Lake Observations by Citizen Scientists and Satellites - Take measurements of lake heights and surface areas to reveal how their water volumes are changing.