Tarmo Virtanen, University of Helsinki

Scientists have long predicted that rapidly warming temperatures in the Arctic could unleash huge amounts of carbon trapped beneath the permafrost. It's one of the tipping points in Earth's climate system that scientists are tracking closely. Now, researchers say thawing in the Arctic could also release significant amounts of nitrous oxide, an even more powerful greenhouse gas trapped below the permafrost, a new study finds.

Why it matters: Nitrous oxide is about 300 times more effective at trapping heat than carbon dioxide. But, despite the fact that more than 67 billion tons of nitrogen are stored in the Arctic permafrost, nearly all of the research on the impacts in the Arctic have focused on carbon releases. Vegetation and water can decrease the amount of nitrous oxide released to varying degrees, but this new study shows that up to a quarter of the Arctic could see significant releases of the gas along with carbon dioxide.

How they did it: Finnish scientists collected 16 samples of peat from Finland's Lapland region and slowly warmed them from underneath to simulate thawing in the lab.

The results: There was a fivefold increase in nitrous oxide emissions from samples of bare peat compared to the amount released when only the surface thaws, which happens seasonally. When plants or lichen were growing on top of a sample, emissions decreased by 90% and they were entirely suppressed in wet samples.

Go deeper

Updated 7 mins ago - Politics & Policy

ActBlue collects a record $91 million in hours after Ginsburg's death

A makeshift memorial in honor of Justice Ruth Bader Ginsburg in front of the U.S. Supreme Court on Sept. 19. Photo: Samuel Corum/Getty Images

ActBlue received a record $91.4 million in the 28 hours following Supreme Court Justice Ruth Bader Ginsburg's death, the Democratic donation-processing site confirmed to Axios late Saturday.

Why it matters via the New York Times: "The unprecedented outpouring shows the power of a looming Supreme Court confirmation fight to motivate Democratic donors."

Updated 2 hours ago - Politics & Policy

Coronavirus dashboard

Illustration: Sarah Grillo/Axios

  1. Global: Total confirmed cases as of 11:30 p.m. ET: 30,674,077 — Total deaths: 955,440— Total recoveries: 20,908,811Map.
  2. U.S.: Total confirmed cases as of 11:30 p.m. ET: 6,764,803 — Total deaths: 199,258 — Total recoveries: 2,577,446 — Total tests: 94,211,463Map.
  3. Politics: In reversal, CDC again recommends coronavirus testing for asymptomatic people.
  4. Health: The dwindling chances of eliminating COVID-19.
  5. World: Guatemalan president tests positive for COVID-19 — The countries painting their pandemic recoveries green.
Updated 6 hours ago - Technology

Trump agrees to TikTok deal

Illustration: Sarah Grillo/Axios

President Trump on Saturday said he approved "in concept" a deal whereby TikTok will be allowed to continue operating in the U.S., with Oracle as its "trusted technology partner."

Why it matters: TikTok has nearly 100 million U.S. users, and is still growing fast. Trump has threatened to ban it, due to data privacy concerns related to TikTok's ownership by Chinese tech company.