Published: Fri, November 09, 2018
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The Ozone layer is healing- Scientific Assessment of Ozone Depletion reveals

The Ozone layer is healing- Scientific Assessment of Ozone Depletion reveals

"It's really good news", said report co-chairman Paul Newman, chief Earth scientist at NASA's Goddard Space Flight Center.

The Assessment, which is meant to add to the scientific basis for decisions made by the Parties to the Montreal Protocol, also presents updated scenarios for hastening ozone recovery through: Complete elimination of controlled and uncontrolled emissions of substances such as carbon tetrachloride and dichloromethane, Bank recapture and destruction of chlorofluorocarbons (CFCs), halons, and hydrochlorofluorocarbons (HCFCs) and Elimination of HCFC and methyl bromide production, as well as the Mitigation of nitrous oxide emissions.

The UN estimates that Northern Hemisphere and mid-latitude ozone should heal completely by the mid-2030s, followed by the Southern Hemisphere in the 2050s and the polar regions by 2060. Higher up in the stratosphere, ozone accumulates at altitudes between 10 and 50 km where it acts as a shield against the harmful ultraviolet rays, which can cause cancer.

It shows that the concentration of ozone-depleting substances continues to decrease, leading to an improvement in the layer since the previous assessment carried out in 2014.

The Kigali Amendment is set to revise targets under the Montreal Protocol, and will mandate the search for alternatives to hydrofluorocarbons (HFCs). Since 2000, it has increased by about 1 to 3 percent per decade, the report said. This year, the ozone hole over the South Pole peaked at about 9.6 million square miles. That's about 16 percent smaller than the biggest hole recorded - 11.4 million square miles (29.6 million square kilometers) in 2006.

The ozone layer starts at about 6 miles (10 kilometers) above Earth and stretches for almost 25 miles (40 kilometers); ozone is a colorless combination of three oxygen atoms.

This is not a complete success, says Brian Toon from the University of Colorado who was not part of this report.

A new technology picked up an increase in emissions of banned CFCs out of East Asia, according to the report.

It is worth noting the fact that informed other teams of specialists and researchers in the field of ecology of the atmosphere in different ways characterized the degree of recovery of the ozone layer, but in General they were inclined to think that the closer to the thirties of this century the recovery of the ozone layer of the Earth's atmosphere will enter a new phase in which scientists will be able to somewhat speed up the process and contribute to its "healing".

CFCs are found in cooling and refrigeration systems, aerosols.

"I don't think we can do a victory lap until 2060", Newman said.

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