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What was discovered over the Antarctic in 1980s?
ozone layer
In 1985 scientists from the British Antarctic Survey shocked the world when they announced the discovery of a huge hole in the ozone layer. The special satellite U.S. NIMBUS 7 passed over Antarctica and recorded the ozone hole [NASA and the National Oceanic and Atmospheric Administration (NOAA)].
Is there still a hole in the ozone layer 2020?
The record-breaking 2020 Antarctic ozone hole finally closed at the end of December after an exceptional season due to naturally occurring meteorological conditions and the continued presence of ozone depleting substances in the atmosphere.
Why is there a hole in the ozone layer over Antarctica?
The Antarctic ozone hole is a thinning or depletion of ozone in the stratosphere over the Antarctic each spring. This damage occurs due to the presence of chlorine and bromine from ozone depleting substances in the stratosphere and the specific meteorological conditions over the Antarctic.
What is the Antarctic ozone hole?
The 2021 Antarctic ozone hole reached its maximum area on Oct. 7 and ranks 13th largest since 1979. What we call the “ozone hole” is a thinning of the ozone layer in the stratosphere (an upper layer of Earth’s atmosphere) above Antarctica that begins every September.
What was the size of ozone hole in 1985?
The maximum depth of the hole that year was 194 Dobson Units (DU)—not far below the previous historical low. For several years, the minimum concentrations stayed in the 190s, but then the minimums rapidly grew deeper: 173 DU in 1982, 154 in 1983, 124 in 1985.
Who was discovered in the year 1984 over Antarctica?
Joseph Farman, a British researcher whose single-minded and at times officially derided study of atmospheric changes in the Antarctic established the existence of a hole in the ozone layer over the South Pole approximately the size of the United States — one of the most important environmental discoveries of the 20th …
Has the Antarctic ozone hole closed?
The Antarctic ozone hole — one of the deepest, largest gap in the ozone layer in the last 40 years — has closed,according to World Meteorological Organization (WMO) January 6, 2021. The same meteorological factors also contributed to the record 2020 Arctic ozone hole, which has also closed.
When was the ozone hole discovered?
1985
In the scientific journal Nature on May 16, 1985, three scientists from the British Antarctic Survey announce their detection of abnormally low levels of ozone over the South Pole.
Who discovered the ozone hole in the Antarctic?
In the mid-1980s, scientists Joe Farman, Brian Gardiner and Jonathan Shanklin opened the world’s eyes to a new phenomenon: “unanticipated and large decreases in stratospheric ozone levels over the Antarctic stations of Halley and Faraday,” which became known as the Antarctic ozone hole, writes Susan Solomon, the EAPS …
When did ozone levels start dropping in Antarctica?
In 1985, Joe Farman, Brian Gardiner and Jonathan Shanklin reported 1 unanticipated and large decreases in stratospheric ozone levels over the Antarctic stations of Halley and Faraday. Their data showed that, after about 20 years of fairly steady values, ozone levels began dropping in the austral spring months around the late 1970s (Fig. 1).
Where does the chlorine in Antarctica come from?
Scientists estimate that about 80 percent of the chlorine (and bromine, which has a similar ozone-depleting effect) in the stratosphere over Antarctica today comes from human, not natural, sources.
What kind of clouds form in the Antarctic?
During the cold dark Antarctic winter, stratospheric ice clouds (PSCs, polar stratospheric clouds) form when temperatures drop below -78C. These clouds are responsible for chemical changes that promote production of chemically active chlorine and bromine.