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Observations from Space help understand Environmental Issues on Earth

This month, as our neighbours and colleagues in the United States celebrated Earth Science week, we look at how one Environment and Climate Change Canada (ECCC) scientist is using Earth Observations from NASA satellites to inform efforts to combat climate change.

Growing up, Ray Nassar was fascinated by space. Now as a research scientist with ECCC, he works with satellites to measure the different gases in the atmosphere that are responsible for many environmental issues. “I feel like I’m doing something with space that is really practical and important for the planet,” he says.

The Element of Chance

In 2017, Nassar led the first study in the world to use satellite observations to quantify CO2 emissions at the scale of an individual power plant. At the time, it was believed that a satellite specifically designed for this task would be required to provide the level of detail necessary. Nassar thought differently. As a science team member of NASA’s Orbiting Carbon Observatory 2 (OCO-2) mission, he and a student searched the data for observations near power plants.

“There is an element of chance involved with the current satellite, OCO-2. People often think that satellites observe every point on the earth, but there are wide gaps between measurements,” Nassar explains.

Despite the gaps, Nassar and his team were able to use modeling together with the satellite data to quantify emissions from a small number of individual power plants to demonstrate that it really was feasible. Their findings showed that improving the satellite design with more detailed observations, could prove to be a powerful tool in quantifying CO2 emissions from power plants or from urban regions where emissions are spatially distributed over a larger area.

Paris Agreement

In 2015, the Paris Agreement was put in place providing a framework for nations around the world to combat climate change. Since then, there has been a growing realization internationally that having more reliable and detailed information about emissions, including sources and sectors, could help reach the ultimate goal of reducing greenhouse gases in the most cost effective way possible. Nassar quotes a common adage in his field, “We can’t manage what we can’t measure.”

The typical approach that most countries use to report their emissions under the Paris Agreement is generally based on accounting. Emissions are reported based on a calculation of the fuel amounts purchased and the time period of burning. Nassar says the global direction for understanding our emissions is to move toward more transparency and greater use of observations. “The research by my group, and many others around the world, uses an observation-based approach with atmospheric measurements to quantifying emissions to see if they are consistent with what we think they are, or suggest that emissions are perhaps higher or lower.”

What’s Next?

Space agencies around the world are currently exploring how to design satellite missions to address different aspects of climate change. “We are facing a global problem and no one country is going to solve it alone,” Nassar says. He is continuing to work with NASA’s OCO-2 satellite mission as well as its recent follow-on, OCO-3, and will release a new paper based on over five years of data. Nassar is also the principal investigator for a proposed satellite project that would measure greenhouse gases, air quality and weather parameters with a specific focus on northern regions, including all of Canada. The Arctic Observing Mission is jointly led by ECCC and the Canadian Space Agency, and has potential for international involvement by the National Oceanic and Atmospheric Administration and NASA.

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