As Seen From Space

Remote sensing expert Claude Duguay is using satellites and AI to monitor how a changing climate is impacting snow and ice across Canada.

What can we uncover by looking at Earth from space? Remote sensing expert Claude Duguay believes we’re just scratching the surface.

Duguay is the University Research Chair in Cryosphere & Hydrosphere from Space at University of Waterloo. He’s also the founding director of University of Waterloo’s Interdisciplinary Centre on Climate Change, and the Principal Investigator of the project Transformative Sensor Technologies and Smart Watersheds. In his work, he focuses on developing new ways to measure – from a great distance – how climate change is impacting the planet.

“We’re interested in building tools to observe and monitor how snow and ice are behaving in a new normal,” he says. “What we learn can help us make practical, informed decisions about water availability and water quality.”

This work requires zooming way, way out. Duguay specializes in remote sensing, the scientific discipline that measures and analyzes the physical characteristics of an area by measuring its reflected and emitted radiation at a distance, typically from satellites and aircraft. He says satellite imaging can tell us a lot about snow, ice, water and ecosystem health.

“By monitoring snowpack, for example, we can help predict how much water will be available downstream for farmers that season,” he says. “We can also better monitor algal blooms and other environmental disasters, such as spills, and help inform the science and policy that can prevent them from happening in the first place.”

Photo: Claude Duguay, Professor, University Research Chair in Cryosphere & Hydrosphere from Space.

Building the tools

With the help of AI and machine learning technology, Duguay and his team convert satellite observations with algorithms to interpret landscape data. This helps build products and instruments that can be used on future satellite missions to help people understand what’s happening on Earth’s surface.

With sensors that we have access to now, we can measure things like soil moisture, the thickness of Arctic sea ice, and water level and volume changes in lakes and rivers. But the technology is changing rapidly, and it’s never quite as easy as snapping a photo, Duguay says. “To build accurate tools, we first need to validate with data from the field. We need to take samples on the ground – or in the water – and ensure the information matches what the satellite sees.”

Through the Global Water Futures (GWF) program, Duguay’s team put sensors on aircraft flying over the western basin of Lake Erie. “At the same time, we had teams in boats taking samples from the lake to validate the results from the flyover,” he explains. “From there, we were able to calibrate our sensors, and train our algorithms. When the Canadian Space Agency is ready to launch their next satellite, the water monitoring instruments will be ready.””

With these tools and with support from international partners, Duguay’s team can now gather information on regional, continental, and global scales. “We can better understand how snow and ice behaviours are affecting water quantity around the globe,” he says.

Measuring changes in Canada’s North

Through GWF, Duguay’s team is also involved in a relatively new area of research that uses the Global Navigation Satellite System (GNSS) – essentially, a constellation of GPS satellites scattered across the skies that provide frequent signals and positioning, navigation, and timing services. At Great Slave and Great Bear Lakes in the Canadian Arctic, the team was able to show that GNSS signals are sensitive to the presence of ice – and its thickness – on lakes and oceans.

“There aren’t a lot of people or monitoring stations up north, but the Canadian Arctic is one of the most vulnerable places in the world when it comes to a changing climate,” he says. “Using satellites can help us determine how the region is being impacted. The technology has improved enough for us to get signals at a very high resolution, which allows us to gather data at a much more local scale.”

Duguay provides an example. “When you’re monitoring ice roads, you need monitoring data every one or two hours to make decisions about road maintenance and safety. This information can make a huge difference for remote Arctic communities with seasonal access to transport. The tools can help them plan for and adapt to a new normal.”
 

The future of remote sensing

Participating in GWF has helped Duguay and his team contribute to cutting-edge research. “The program gave us new opportunities to work with both government and high-tech industry from across the globe, building and testing instruments and solutions to meet their needs,” he says.

“Unlike some funding models, GWF encouraged us to think outside of the box. When we’re working on tools for space missions, for instance, we’re working toward launches that won’t happen for another five to 10 years. We must anticipate what might be needed, test the concepts, and demonstrate their potential. There’s some risk involved.”

Duguay says remote sensing technology – and the data we can gather from it – is changing all the time. “In many ways, we’re still on the fringes,” he says. “The technology has evolved incredibly since I first started my career, and there is still so much ahead of us. We can learn a lot about our planet from space.”

Listing photo by SpaceX.