A satellite with a 40-foot extendible antenna has launched into space with a giant mission: to map all of the world’s forests, ecosystems that are crucial for sucking up carbon and slowing climate change.
The Biomass mission will paint a detailed global picture of Earth’s forests, the European Space Agency said, peeking beneath their canopies to reveal where they are thickest and how that is changing — including as a result of climate change and deforestation. Scientists say the data will offer a glimpse into the carbon-zapping capabilities of one of Earth’s best defenses against climate change.
The Vega-C rocket containing the satellite successfully launched into space at 6:16 a.m. local time from Europe’s spaceport in Kourou, French Guiana, the ESA said. The umbrella-shaped satellite, built by Airbus, will orbit Earth about 15 or 16 times a day at an altitude of 413 miles for five years.
“It will effectively weigh forests and how much wood is in forests,” Shaun Quegan, the mission’s lead scientist, said in an interview Tuesday. “When you look from above, what you see is leaves. This satellite doesn’t see the leaves at all. It sees right through the leaves to the bits below, which is where all the wood — and half of the world’s carbon — is. It tells us what’s happening to carbon as the world’s forests are destroyed and as they grow.”
Quegan, a mathematician and physicist at the University of Sheffield, said he cried with emotion as he watched the launch from the ESA’s operation center in Darmstadt, Germany. “We waited and waited. It was like hearing the first cry of the baby.”
Quegan first conceived of using a P-band radar to map the world’s forests about 20 years ago. Up until 2004, the technology was restricted to use by the U.S. Defense Department, he said. The radar’s unusually long wavelength allows it to pierce through the leaves and small branches of a forest’s thick canopy and measure the woody trunks, branches and leaves that sit beneath.
It is then bounced back to the satellite in space, which captures the data on a 40-foot deployable antenna.
That calculation — forest biomass — is important “because it’s a significant reservoir of carbon in the Earth’s system, and it’s not something at the moment that we have a really strong handle on, ” said Tristan Quaife, a climate scientist at the University of Reading and Britain’s National Center for Earth Observation who was not involved in the mission. Climate change, deforestation and other human factors are eroding the capabilities of forests to absorb carbon dioxide.
Matt Disney, an environmental scientist at University College London who is contributing research to the space mission, stepped away from a watch party with other scientists in London for a phone interview Tuesday, shortly after the successful launch.
He said the P-radar will collect swaths of data on each orbit it makes around Earth. He said it has been calibrated to focus initially on the tropics, where detailed biomass data is lacking. The mission will then use biomass data collected through fieldwork by other scientists, including Disney, to calibrate the satellite and ensure its conversion of data into biomass estimates is accurate.
Previously, scientists estimated biomass by extrapolating data from field measurement — which is difficult to collect at a large scale. In particular, information on remote forests in the tropics — where half of the world’s trees are — is patchy.
“If you’re going to start basing policy and making international agreements around what we should be doing to protect forests and how much money we should spend on doing that, then you need to have numbers that are both credible and that people will sign up to,” Disney said.
Tuesday’s launch represents the first attempt to map Earth’s forest biomass on a global scale using this type of radar, the scientists said. It will join other satellites to form a constellation of satellites in space tracking woodland forest cover.
NASA’s GEDI instrument on the International Space Station provides detailed observations about forest canopies, but it uses smaller lasers that cannot collect the same level of data. A Japanese satellite uses L-band radar to monitor forest cover, but it can’t penetrate beneath the canopy in the same way as Biomass.
Other efforts to map every tree on Earth have used artificial intelligence on existing satellite images.
Scientists have previously tracked deforestation at a local level, but it has been difficult to measure forest vegetation levels in a globally consistent way.
The existing studies do not paint a positive picture. One published in 2020 found that the rainforest in central Africa’s Congo Basin was losing its capacity to absorb carbon dioxide, apparently as a result of drought and increasing heat. Under Brazilian President Jair Bolsonaro, deforestation of the Amazon rainforest — which is estimated to store 123 billion tons of carbon — reached a 15-year high, The Washington Post reported in 2022.
Disney said the initial first light data will be available to the space mission within days, and the first publicly available data will be available in about a year.