A map of the hole in the ozone layer over Antarctica on Oct. 20. Photo: NASA

The hole in the ozone layer over Antarctica has shrunk to the smallest size since it was discovered by scientists in the 1980s, NASA said in a statement this week.

Yes, but: "It’s not a sign that atmospheric ozone is suddenly on a fast track to recovery," said Paul Newman, chief scientist for Earth Sciences at NASA's Goddard Space Flight Center in Greenbelt, Maryland, in the statement. It's important to recognize that what "we’re seeing this year is is due to warmer stratospheric temperatures," he said.

The big picture: Scientists from NASA and NOAA who monitor the hole in the ozone are still trying to understand the rare shrinkage event that they believe is weather-related, according to Susan Strahan, an atmospheric scientist with Universities Space Research Association, who works at NASA Goddard.

  • "If the warming hadn’t happened, we’d likely be looking at a much more typical ozone hole," Strahan said in the statement.
  • This is the third time in the past 40 years that weather systems have caused warm temperatures that limit ozone depletion, Strahan said. In September 1988 and 2002, similar weather patterns produced atypically small ozone holes, she said.

By the numbers: NASA and NOAA satellite measurements show the annual ozone hole reached its peak extent of 6.3 million square miles on Sept. 8, and then shrank to less than 3.9 million square miles for the rest of the month through October.

"During years with normal weather conditions, the ozone hole typically grows to a maximum area of about 8 million square miles in late September or early October."
— NASA statement

But, but, but: There is still reason to cheer at the news. NASA scientist Paul Newman told AP it means there's more ozone covering the Southern Hemisphere and "less ultraviolet radiation at the surface."

  • NASA says the 1987 treaty the Montreal Protocol on Substances that Deplete the Ozone Layer, signed by almost 200 countries to regulate the consumption and production of ozone-depleting compounds, is also starting to have a positive impact.
  • The ozone hole over Antarctica is expected to gradually become less severe as chlorofluorocarbons (CFCs), which used to be found in refrigerators and aerosols but were banned under the protocol, are declining. "Scientists expect the Antarctic ozone to recover back to the 1980 level around 2070," NASA said.

Go deeper: Chinese factories are using banned ozone-depleting chemicals

Go deeper

Updated 2 hours ago - Politics & Policy

Coronavirus dashboard

Illustration: Sarah Grillo/Axios

  1. Global: Total confirmed cases as of 3 a.m. ET: 31,032,045 — Total deaths: 960,729— Total recoveries: 21,255,717Map.
  2. U.S.: Total confirmed cases as of 3 a.m. ET: 6,805,342 — Total deaths: 199,511 — Total recoveries: 2,590,671 — Total tests: 95,108,559Map.
  3. Politics: Testing czar on Trump's CDC contradictions: "Everybody is right" Ex-FDA chief: Career scientists won't be "easily cowed" by political vaccine pressure.
  4. Education: What we overlooked in the switch to remote learning.
  5. Health: The dwindling chances of eliminating COVID-19 — 7 states set single-day coronavirus case records last week.
  6. World: England sets £10,000 fine for breaking self-isolation rules — The countries painting their pandemic recoveries green.
Updated 2 hours ago - Politics & Policy

Biden raises $141 million more than Trump

Combination images of President Trump and his 2020 presidential rival Joe Biden. Photo: Sarah Silbiger/Getty Images/Alex Wong/Getty Images

Joe Biden's campaign, the Democratic National Committee and joint fundraising committees raised $466 million cash on hand, the presidential candidate's team announced late Sunday.

Why it matters: President Trump's campaign raised $325 million cash on hand, his campaign communications director Tim Murtaugh announced Friday. In the spring, Biden was $187 million behind Trump and the Republican National Committee.

Virtual Emmys address chaotic year for American TV and society

Emmy Host Jimmy Kimmel during rehearsals Friday for the 72nd Annual Emmy Awards at the Staples Center in Los Angeles. Photo: Al Seib/ Los Angeles Times via Getty Images

The Emmy Awards Sunday night addressed the major U.S. issues this year — including the protests on systemic racism and police brutality, the wildfires engulfing parts of the West Coast, the census, the pandemic, essential works and the election.

Why it matters: Award shows have always addressed wider cultural issues, but this year — amid unprecedented stress and uncertainty — that trend has accelerated.