UN: Earth's Ozone Layer Is Slowly Healing
2023-01-11
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1A United Nations report has found that Earth's protective ozone layer is slowly healing itself.
2Ozone is a form of oxygen. In Earth's upper atmosphere, it acts as a barrier to block harmful radiation from the sun.
3But closer to Earth's surface, ozone is a common pollutant.
4At ground level, high levels of ozone can harm people's lungs and damage plants.
5Research has shown that chemical pollutants released into the atmosphere shrink the ozone layer over time.
6The layer exists in a part of Earth's atmosphere known as the stratosphere.
7The layer sits between 15 to 30 kilometers above Earth's surface.
8Each year, a large hole develops in the layer over Antarctica.
9In their new report, U.N. scientists say at the current rate, the ozone hole over Antarctica would be fully healed by 2066.
10Paul Newman is the co-chair of the U.N. report.
11It was recently presented at a meeting of the American Meteorological Society.
12He told The Associated Press, "In the upper stratosphere and in the ozone hole we see things getting better."
13However, the researchers reported the healing is happening very slowly.
14The worldwide average amount of ozone is estimated to return to pre-thinning levels around 2040, the report said.
15A 1987 agreement called the Montreal Protocol banned a series of chemicals - mainly used in refrigerants and aerosols - believed to have reduced the thickness of the ozone layer.
16The Secretary-General of the World Meteorological Organization, Petteri Taalas, commented about the report in a statement.
17He said past actions taken to reduce ozone damage had demonstrated the importance of limiting climate-harming substances.
18Newman added that while signs of healing were reported four years ago, researchers were looking for more lasting change.
19The earlier recovery numbers had "solidified a lot," he said.
20The two main chemicals that eat away at ozone are in lower levels in the atmosphere, said Newman, who is also the chief Earth scientist at NASA's Goddard Space Flight Center.
21The report said chlorine levels were down 11.5 percent since they reached a high in 1993.
22Bromine - which does a better job of eating ozone but exists at lower levels in the air - dropped 14.5 percent since reaching a high point in 1999.
23Newman said the reductions in chlorine and bromine levels came largely because of the limits set in the Montreal Protocol.
24Another member of the research team was David W. Fahey, director of the U.S. National Oceanic and Atmospheric Administration's chemical sciences lab.
25He said the latest results show there has been a "sea change" in the way the world deals with its ozone-thinning substances.
26Natural weather cycles in the Antarctic also affect ozone hole levels, which are highest in the autumn.
27The past few years, Newman said, the ozone hole grew a bit bigger because of that. But overall, the results demonstrate clear healing, the report said.
28I'm Bryan Lynn.
1A United Nations report has found that Earth's protective ozone layer is slowly healing itself. 2Ozone is a form of oxygen. In Earth's upper atmosphere, it acts as a barrier to block harmful radiation from the sun. But closer to Earth's surface, ozone is a common pollutant. At ground level, high levels of ozone can harm people's lungs and damage plants. 3Research has shown that chemical pollutants released into the atmosphere shrink the ozone layer over time. The layer exists in a part of Earth's atmosphere known as the stratosphere. The layer sits between 15 to 30 kilometers above Earth's surface. Each year, a large hole develops in the layer over Antarctica. 4In their new report, U.N. scientists say at the current rate, the ozone hole over Antarctica would be fully healed by 2066. 5Paul Newman is the co-chair of the U.N. report. It was recently presented at a meeting of the American Meteorological Society. He told The Associated Press, "In the upper stratosphere and in the ozone hole we see things getting better." 6However, the researchers reported the healing is happening very slowly. The worldwide average amount of ozone is estimated to return to pre-thinning levels around 2040, the report said. 7A 1987 agreement called the Montreal Protocol banned a series of chemicals - mainly used in refrigerants and aerosols - believed to have reduced the thickness of the ozone layer. 8The Secretary-General of the World Meteorological Organization, Petteri Taalas, commented about the report in a statement. He said past actions taken to reduce ozone damage had demonstrated the importance of limiting climate-harming substances. 9Newman added that while signs of healing were reported four years ago, researchers were looking for more lasting change. The earlier recovery numbers had "solidified a lot," he said. 10The two main chemicals that eat away at ozone are in lower levels in the atmosphere, said Newman, who is also the chief Earth scientist at NASA's Goddard Space Flight Center. The report said chlorine levels were down 11.5 percent since they reached a high in 1993. Bromine - which does a better job of eating ozone but exists at lower levels in the air - dropped 14.5 percent since reaching a high point in 1999. 11Newman said the reductions in chlorine and bromine levels came largely because of the limits set in the Montreal Protocol. 12Another member of the research team was David W. Fahey, director of the U.S. National Oceanic and Atmospheric Administration's chemical sciences lab. He said the latest results show there has been a "sea change" in the way the world deals with its ozone-thinning substances. 13Natural weather cycles in the Antarctic also affect ozone hole levels, which are highest in the autumn. The past few years, Newman said, the ozone hole grew a bit bigger because of that. But overall, the results demonstrate clear healing, the report said. 14I'm Bryan Lynn. 15The Associated Press reported this story. Bryan Lynn adapted the report for VOA Learning English. 16__________________________________________________________________ 17Words in This Story 18layer - n. an amount of substance covering a surface 19refrigerant - n. a chemical substance that can be used to make things or keep things cold 20aerosol - n. a substance like hair spray kept in a container under pressure that is released in a fine spray when a button is pushed 21sea change - n. a complete change or transformation 22___________________________________________________________________ 23What do you think of this story? We want to hear from you. We have a new comment system. Here is how it works: 24Each time you return to comment on the Learning English site, you can use your account and see your comments and replies to them. Our comment policy is here.