If the ozone layer was absent, millions of people would develop skin diseases and may have weakened immune systems. By October 1, 2010, the value was back up to 118 DU. Fact Check: What Power Does the President Really Have Over State Governors? NASA satellites have observed the Antarctic ozone hole since the late 1970s—before and after nations agreed to stop producing chemicals that destroy the ozone layer. Ozone layer depletion increases the amount of UVB that reaches the Earth’s surface. Climate 101: Ozone Depletion ), The Secret Science of Solving Crossword Puzzles, Racist Phrases to Remove From Your Mental Lexicon. There have been some attempts to reduce emissions to slow the damage, such as regulating vehicles and removing types of aerosols that were high in CFC's, but much debate remains on the correct course of action to correct the issue. The largest hole observed was in 2006; it was 76.30 million square kilometers in area (29.46 million square miles); no hole in subsequent years, as of 2014, has been as large. World governments were quick to react, reaching an agreement in Montreal in 1987 to, by 2010, phase out CFC use among countries that signed. The measures taken to repair the damage … The seasons have an impact on the Antarctic ozone hole. This ozone damages plants and causes breathing issues for some people. It is a cause of melanoma and other types of skin cancer. There are numerous pictures of cities such as Los Angeles where the air appears brown from the smog and pollution created by the high number of people and cars in the city. The lowest value (deepest hole) ever recorded was 73 Dobson Units on September 30, 1994, while the broadest hole occurred on September 29, 2000, when the ozone-depleted area stretched 29.9 million square kilometers. CFCs are tasteless, odorless, nonflammable and noncorrosive, but in 1974, two scientists warned that they are far from harmless, and their warnings were confirmed in 1985.

The ozone layer protects the Earth against most UVB coming from the sun. Prior to 2000, both ozone depletion and rising CO2 levels pushed the near-surface circulation poleward. Exposure to solar UVB radiation has been shown to affect both orientation and motility in phytoplankton, resulting in reduced survival rates for these organisms. “Identifying the ozone-driven pause in circulation trends in real-world observations confirms, for the first time, what the scientific ozone community has long predicted from theory,” said John Fyfe, a scientist at Environment and Climate Change Canada and one of the paper’s co-authors. Once in the atmosphere, CFCs drift slowly upward to the stratosphere, where they are broken up by ultraviolet radiation, releasing chlorine atoms, which are able to destroy ozone molecules. Image of the Day Various ozone-depleting substances (ODS), however, accelerate the destruction processes, resulting in lower than normal ozone levels. • The ozone hole over the Antarctic is expected to recover much later. Since the ozone layer absorbs UVB ultraviolet light from the sun, ozone layer depletion increases surface UVB levels (all else equal), which could lead to damage, including an increase in skin cancer. “Ozone holes” are popular names for areas of damage to the ozone layer. Images above the graph show a view of the South Pole in October over time including measurements taken in the past in 1971 and 2017 and model projections of ozone over the area for 2041 and 2065. The damage to the lower atmosphere is actually an increase in what is considered bad ozone. The ozone layer contains less than 10 parts per million of ozone, while the average ozone concentration in Earth's atmosphere as a whole is about 0.3 parts per million. These changes can have important implications for plant competitive balance, herbivory, plant diseases, and biogeochemical cycles. The ozone layer, in the stratosphere, is where about 90% of the ozone in the Earth system is found. The ozone layer or ozone shield is a region of Earth's stratosphere that absorbs most of the Sun's ultraviolet radiation. “It’s the tug of war between the opposing effects of ozone recovery and rising greenhouse gases that will determine future trends.”. The most severe effects are decreased reproductive capacity and impaired larval development.

(NASA). Ozone near the ground is a pollutant, but in the upper stratosphere, it forms a protective layer around the planet that absorbs ultraviolet sunlight, thereby protecting all life from the harmful effects of that radiation. Science Fair Project Ideas for Kids, Middle & High School Students, U.S. Environmental Protection Agency: The Process of Ozone Depletion, NASA: NASA Pinpoints Causes of 2011 Arctic Ozone Hole. Scientists have demonstrated a direct reduction in phytoplankton production due to ozone depletion-related increases in UVB. However, a 2018 report from the United Nations says that the infamous hole in the ozone layer could be totally healed by the 2060s—and in some areas of the world, it could be as soon as 2030. • At mid-latitudes, surface ultraviolet radiation has been about constant over the last decade. Because all sunlight contains some UVB, even with normal stratospheric ozone levels, it is always important to protect your skin and eyes from the sun. These potential changes would contribute to biosphere-atmosphere feedbacks that mitigate or amplify the atmospheric concentrations of these gases. Phytoplankton productivity is limited to the euphotic zone, the upper layer of the water column in which there is sufficient sunlight to support net productivity. The ozone layer is steadily repairing itself following a drastic global reduction in the use of ozone-depleting substances, the UN's environmental agency has found. Since the agreement was signed, these targets have been strengthened to call for the elimination of the most dangerous CFCs by 1996 and for regulation of other ozone-depleting chemicals. The ozone hole, discovered in 1985, has been forming every spring in the atmosphere high over Antarctica. Ozone depletion cools the air, strengthening the winds of the polar vortex and affecting winds all the way down to the lowest layer of Earth’s atmosphere. At other times, it’s smaller. The same international agreement that successfully put the ozone layer on the road to recovery is now being used to address climate change. “This study adds to growing evidence showing the profound effectiveness of the Montreal Protocol. Now, new research published this week in Nature finds that those changes have paused and might even be reversing because of the Montreal Protocol—an international treaty that successfully phased out use of ozone-depleting chemicals. Does Your Nutrition Company Feed Hungry Kids at the Same Time? Copyright 2020 Leaf Group Ltd. / Leaf Group Media, All Rights Reserved. The damage to the upper atmosphere and what is referred to as good ozone has more long term effects on the planet. Since 2000, CO2 has continued to push this circulation poleward, balancing the opposing effect of the ozone recovery. The 2010 Assessment of the Scientific Assessment Panel. However, these precautions will become more important as ozone depletion worsens. The record for mean size of the ozone hole—the greatest extent over a one-month window—was September 7 to October 13, 2006, when the hole reached 26.2 million square kilometers. Ozone absorbs the most energetic wavelengths of ultraviolet light, known as UV-C and UV-B, wavelengths that harm living things. Using computer simulations, the researchers first determined that the observed pause in circulation trends couldn’t be explained by natural shifts in winds alone. • The ozone layer outside the Polar Regions is projected to recover to its pre-1980 levels some time before the middle of this century.