SAN FRANCISCO – Air pollution has fallen dramatically in many areas of China as activity slows due to the COVID-19 pandemic. Some parts of Beijing, though, have experienced little relief because work continues at nearby power plants and steel mills.

That was the conclusion of a Finnish Centre for Research on Energy and Clean Air (CREA) study that relied on imagery from Planet’s constellation of Earth observation satellites.

“There was an assumption that as lockdown occurred, pollution levels would plummet,” Paris Good, Planet customer success manager, told SpaceNews. Even though factories shut down, construction halted and people stopped driving, steel and power plants were still operating, she added.

Researchers monitoring pollution levels via satellite usually gather data from spectrometers like the Tropospheric Monitoring Instrument on the European Space Agency’s Sentinel-5P satellite. Instead, CREA lead analyst Lauri Myllyvirta visually inspect powerplant plumes with Planetscope, Planet’s three-meter-resolution imagery, “to get a sense of how much fuel combustion is taking place,” Good said. CREA combined those observations with data on particulate matter in the atmosphere to calculate fossil fuel consumption, she added.

CREA obtains the Planet imagery through Satellites for Climate Action, a partnership announced at the 2019 Bloomberg Global Business Forum in New York. Satellites for Climate Action is backed by Bloomberg Philanthropies, Planet and the State of California.

The coronavirus pandemic is highlighting the value of satellites to provide information government agencies either “don’t have the capability to measure or aren’t willing to share,” said Antha Williams, Bloomberg Philanthropies environmental program lead. Satellites also are helping low- and middle-income countries find inexpensive ways to measure pollution and put data in the hands of decisionmakers, she added.

Satellites for Climate Action currently supports two organizations: CREA and Carbon Tracker, a financial think tank based in London. While CREA focuses on China, Carbon Tracker draws on satellite imagery to estimate production capacity for coal power plants around the world.

“There is a general understanding that we need large-scale action on climate change and sustainable development, but there hasn’t been a practical and cost-effective way to measure progress on a global scale,” Good said. “This is where remote sensing satellite imagery can show real progress.”

Satellites for Climate Action is eager to bring on additional partners. “We’re talking to a group in Brazil monitoring deforestation down to the field level,” Good said. “We hope to get them involved shortly.”

Planet receives grants from Bloomberg Philanthropies for its Satellites for Climate Action work.