Counting Carbon: How Satellites and Lasers Are Mapping the World's Forests
Forests store huge amounts of carbon, likely hundreds of billions of tons. One metric ton is about 2,200 pounds, so hundreds of billions of tons is... let's just say it's a lot. Because trees pull carbon dioxide out of the air and lock it away, forests play a major role in controlling Earth's climate.
To figure out how much carbon a forest holds, scientists can measure individual trees, like how wide the trunk is and how tall the tree grows. But nobody can take a tape measure to millions of square miles of forest, and "a whole bunch" isn't a scientific measurement.
That's where new technology comes in. In 2025, the European Space Agency, which runs space missions for a group of European countries, launched a satellite called Biomass. It uses radar with extra-long wavelengths. The longer the wavelength, the more easily radar can pass through leaves and small branches and pick up bigger things, like trunks and large branches, which hold most of a tree's carbon.
Most earlier satellites, like many launched by NASA, the U.S. space agency, are optical. They work like cameras, capturing sunlight reflected off the treetops. That's useful for seeing where forests are, but it mostly shows the top layer. Radar can reveal what's underneath. It can help scientists estimate how much wood a forest holds, spot deforestation, and study flooded forests that are hard to reach. Scientists then check the satellite data against measurements taken from planes and on the ground.
Another tool is LiDAR, short for Light Detection and Ranging. It sends out pulses of laser light and measures how long they take to bounce back, building detailed 3D maps of forests. Some are precise enough to show individual twigs and leaves. LiDAR isn't new, but it produces enormous amounts of data. Artificial intelligence is now making that data much faster to process, turning LiDAR into a more practical tool for studying forests.
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The Hawk Fire started near Reno, Nevada, on Aug. 22 and burned for days. Evacuation orders stayed in place for more than a week. Firefighters didn't declare the fire 100% contained until Sept. 10. "Contained" means crews had built barriers all the way around the fire so it could no longer spread. While the fire burned, tens of thousands of people had to leave their homes, many with little more than the clothes they were wearing.
Emergency alerts told Reno residents to get out, even though no one could say when they'd be able to return or what shape their homes would be in.
Fighting a fire this big took the whole community. Evacuation centers gave people shelter, food, and donated clothing. Firefighters attacked the flames, helicopters dropped water, and crews strengthened containment lines. These lines are strips of land cleared of anything that can burn, so the fire has nothing to feed on.
Even once the fire was about 25% contained, strong winds could still spread it through the dry, easily burned plants. That's part of why getting people home took so long. Even after some residents were allowed back, around 40,000 people were still under evacuation warnings.
Late on Friday, Sept. 4, Indonesia's Anak Krakatau volcano began erupting, and it didn't stop for about 25 hours. It sent lava and volcanic ash up to 50,000 feet into the sky, which is almost 10 miles.
The ash drifted toward Jakarta, Indonesia's capital, and thickened the air so much that airports had to shut down. Nearly 3,000 flights were canceled or delayed, and hundreds of thousands of passengers were left stranded.
The ash affected people on the ground too. Residents found volcanic dust settling on homes and balconies. Health officials advised people to stay indoors and wear masks to protect their lungs, eyes, and skin.
Officials planned to use cloud seeding to clear the air. Cloud seeding is a way of changing the weather that helps clouds produce rain, which can wash ash out of the sky. In the end, a shift in the wind blew the ash away, and the air became clear enough for the airports to reopen.
Picture a hedgehog on a hot summer day, and you might imagine it lounging on the beach in tiny sunglasses with a glass of lemonade. In reality, heat can make life tough for hedgehogs.
Hedgehogs are small, spiky mammals that live in the wild in parts of Asia, Africa, and Europe, including the United Kingdom. They aren't found in the wild in North America. Hot, dry weather can cause them serious problems, like dehydration, parasites and trouble finding food. That's hard enough for any animal, but it's even harder for hedgehogs that are pregnant or raising their babies, called hoglets.
That's why one hedgehog rescue center was packed this summer, caring for more than 80 animals at once. It was the busiest June the center had ever seen.
In places where wild hedgehogs live, people can help without working at a rescue. They can leave out fresh water and dry kitten food. They should avoid milk, bread, grains, fruit and vegetables, which can make hedgehogs sick. As the saying goes, not all heroes wear capes. To a hedgehog, some of them leave out kitten food!
“Beautiful on the inside” may be weirdly appropriate for bugs, considering the 3D map of the male fruit fly brain and nervous system more closely resembles a museum-worthy mosaic or a bowl of fruity cereal than the tiny nuisance you’re used to seeing flying around your apples. Scientists recently created this colorful detailed map by slicing and analyzing every nerve cell with an electron microscope — that’s a microscope that uses accelerated electrons instead of visible light to produce images that can be both extremely magnified and incredibly clear at the same time.
The same team previously mapped a female fly brain a couple of years ago and compared the male and female brains to see that roughly 95% of their brain wiring was similar, while about 5% differed.
But those small differences make for some big differences in behavior, including courtship, aggression, detecting competitors, and producing a “love song” by beating the wings.
It's not news (to these scientists, at least) that just two genes were linked to these behaviors, but comparing these 3D maps helped them learn more about the connection between those genes and the specific brain circuits producing the behavior.
Researchers hope the same logic around connecting genes to brain wiring to behavior can eventually be applied to other animals and maybe even humans! This might help scientists investigate conditions with strong genetic influences, including schizophrenia and autism.
The Hawk Fire started near Reno, Nevada, on Aug. 22 and burned for days. Evacuation orders stayed in place for more than a week. Firefighters didn't declare the fire 100% contained until Sept. 10. "Contained" means crews had built barriers all the way around the fire so it could no longer spread. While the fire burned, tens of thousands of people had to leave their homes, many with little more than the clothes they were wearing.
Emergency alerts told Reno residents to get out, even though no one could say when they'd be able to return or what shape their homes would be in.
Fighting a fire this big took the whole community. Evacuation centers gave people shelter, food, and donated clothing. Firefighters attacked the flames, helicopters dropped water, and crews strengthened containment lines. These lines are strips of land cleared of anything that can burn, so the fire has nothing to feed on.
Even once the fire was about 25% contained, strong winds could still spread it through the dry, easily burned plants. That's part of why getting people home took so long. Even after some residents were allowed back, around 40,000 people were still under evacuation warnings.
Late on Friday, Sept. 4, Indonesia's Anak Krakatau volcano began erupting, and it didn't stop for about 25 hours. It sent lava and volcanic ash up to 50,000 feet into the sky, which is almost 10 miles.
The ash drifted toward Jakarta, Indonesia's capital, and thickened the air so much that airports had to shut down. Nearly 3,000 flights were canceled or delayed, and hundreds of thousands of passengers were left stranded.
The ash affected people on the ground too. Residents found volcanic dust settling on homes and balconies. Health officials advised people to stay indoors and wear masks to protect their lungs, eyes, and skin.
Officials planned to use cloud seeding to clear the air. Cloud seeding is a way of changing the weather that helps clouds produce rain, which can wash ash out of the sky. In the end, a shift in the wind blew the ash away, and the air became clear enough for the airports to reopen.
Picture a hedgehog on a hot summer day, and you might imagine it lounging on the beach in tiny sunglasses with a glass of lemonade. In reality, heat can make life tough for hedgehogs.
Hedgehogs are small, spiky mammals that live in the wild in parts of Asia, Africa, and Europe, including the United Kingdom. They aren't found in the wild in North America. Hot, dry weather can cause them serious problems, like dehydration, parasites and trouble finding food. That's hard enough for any animal, but it's even harder for hedgehogs that are pregnant or raising their babies, called hoglets.
That's why one hedgehog rescue center was packed this summer, caring for more than 80 animals at once. It was the busiest June the center had ever seen.
In places where wild hedgehogs live, people can help without working at a rescue. They can leave out fresh water and dry kitten food. They should avoid milk, bread, grains, fruit and vegetables, which can make hedgehogs sick. As the saying goes, not all heroes wear capes. To a hedgehog, some of them leave out kitten food!
“Beautiful on the inside” may be weirdly appropriate for bugs, considering the 3D map of the male fruit fly brain and nervous system more closely resembles a museum-worthy mosaic or a bowl of fruity cereal than the tiny nuisance you’re used to seeing flying around your apples. Scientists recently created this colorful detailed map by slicing and analyzing every nerve cell with an electron microscope — that’s a microscope that uses accelerated electrons instead of visible light to produce images that can be both extremely magnified and incredibly clear at the same time.
The same team previously mapped a female fly brain a couple of years ago and compared the male and female brains to see that roughly 95% of their brain wiring was similar, while about 5% differed.
But those small differences make for some big differences in behavior, including courtship, aggression, detecting competitors, and producing a “love song” by beating the wings.
It's not news (to these scientists, at least) that just two genes were linked to these behaviors, but comparing these 3D maps helped them learn more about the connection between those genes and the specific brain circuits producing the behavior.
Researchers hope the same logic around connecting genes to brain wiring to behavior can eventually be applied to other animals and maybe even humans! This might help scientists investigate conditions with strong genetic influences, including schizophrenia and autism.