Norway is the largest exporter of salmon in the world. And while some of those fish are wild-caught, many are raised in "fish farms"- large cylindrical pens made of nylon in the open water. Sometimes these farmed fish escape, mixing with the local population and causing ecological issues. In a story we first brought you in October, we see farmed fish in a Norwegian fjord and hear about potential solutions to the problem.

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In the early 20th century, a blight fungus wiped out most of the 4 billion American chestnut trees on the eastern seaboard. The loss was ecologically devastating. Short Wave host Emily Kwong dives deep into how scientists are trying to resurrect the American chestnut tree — and recent controversy over a plan to plant genetically modified chestnuts in the wild.

Want to hear about more efforts to recover endangered or lost species? Let us know by emailing shortwave@npr.org!

NPR's Juana Summers talks with Martin Cheek, a conservation botanist for the Royal Botanic Gardens, about new plant and fungus species he and his colleagues discovered this year.

It's looking like 2024 will be the hottest year since record-keeping began, unseating 2023 for the top spot. Climate change is playing a role, and scientists say it was even hotter than expected.

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Vehicle dealers are pushing back on rules that would increase the number of electric trucks sold in New Jersey. It could be a preview of a brewing fight over state rules about cars.

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One of modern history's worst natural disasters, the tsunami left about 230,000 dead across a dozen countries.

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About the size of Rhode Island, the iceberg known as A23a got stuck in an ocean vortex this summer, spinning in place for months. Now, it's free, and heading back into open Antarctic waters.

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The Biden administration has approved California's plan to require new vehicles sold in the state by 2035 to have zero-emissions. President-elect Trump has said he would role back the rules.

Old mines leave behind a a pressing problem: Huge holes that make the landscape look like a chunk of swiss cheese. But in Germany, some scientists and city planners are turning these into lakes.

The largest one will be the biggest artificial lake in Germany when it's done, with a shoreline of 26 kilometers or about 16 miles all around.

But it's not as easy as simply filling the holes with water. It takes a LOT of research to get this science right.

Interested in more environmental stories? Email us at shortwave@npr.org. We'd love to hear from you!

Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave.

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Granholm's statement came as the Energy Department released a long-awaited study that found U.S. LNG shipments drive up domestic wholesale prices and frequently displace renewable energy sources.

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Instead of regulating harmful agricultural runoff, Iowa -- the nation's biggest corn-producing state -- backs a voluntary, industry-friendly program. But it's not as effective as advertised.

A decade of effort to win more water from the Colorado River is finally paying for the Navajo Nation. The Infrastructure Act is funding new irrigated farms now that the desert tribe can legally pull water from the river.

Amidst exceptionally dangerous wildfire conditions, a blaze broke out late Monday in Malibu, California. Firefighters say difficult conditions are expected through Wednesday.

U.S. officials decided to extend protections to monarch butterflies after warnings from environmentalists that populations are shrinking and the beloved pollinator may not survive climate change.

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President Biden helped avert a crisis on the Colorado River by paying farmers and cities $28 million in IRA funds to not take water out of the river. States fear a future without those payments.

Arctic tundra is releasing greenhouse gases into the atmosphere as hotter temperatures melt frozen ground and wildfires increase.

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If you crossed WALL-E with a floor lamp, it might look a little like the PhytoPatholoBot. These robots aren't roving through space or decorating a living room — they're monitoring the stems, leaves and fruit of Cornell AgriTech's vineyards, rolling down each row and scanning for mildew.

In this episode, host Emily Kwong and producer Hannah Chinn take a trip to Cornell to check out these new robots. How do they work? How effective are they? And what do local grape farmers – and neighbors – think about them?

Interested in more robotics stories? Email us at shortwave@npr.org. We'd love to hear from you!

The Canadian government says a new regulation will make shipping on the Great Lakes more environmentally sound. However American shippers say it puts them at a trade disadvantage.

Hurricane Helene swept through several North Carolina Christmas tree farms, but despite some losses there are plenty of trees left at least for this holiday season.

Scientists have pointed out that extreme heat is particularly dangerous for older people. A new study shows that young, healthy people are also dying too often in extreme weather.

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