Warm air helped make 2017 ozone hole smallest since 1988Leave a Comment
- Scientists said the smaller ozone hole extent in 2016 and 2017 is due to natural variability and not a signal of rapid healing.
November 2, 2017 NASA/Goddard Space Flight Center Read full ScienceDaily article here
Measurements from satellites this year showed the hole in Earth’s ozone layer that forms over Antarctica each September was the smallest observed since 1988, scientists have announced…
….The ozone hole over Antarctica is expected to gradually become less severe as chlorofluorocarbons — chlorine-containing synthetic compounds once frequently used as refrigerants — continue to decline. Scientists expect the Antarctic ozone hole to recover back to 1980 levels around 2070.
Ozone is a molecule composed of three oxygen atoms that occurs naturally in small amounts. In the stratosphere, roughly 7 to 25 miles above Earth’s surface, the ozone layer acts like sunscreen, shielding the planet from potentially harmful ultraviolet radiation that can cause skin cancer and cataracts, suppress immune systems and also damage plants. Closer to the ground, ozone can also be created by photochemical reactions between the sun and pollution from vehicle emissions and other sources, forming harmful smog.
Although warmer-than-average stratospheric weather conditions have reduced ozone depletion during the past two years, the current ozone hole area is still large compared to the 1980s, when the depletion of the ozone layer above Antarctica was first detected. This is because levels of ozone-depleting substances like chlorine and bromine remain high enough to produce significant ozone loss.