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Ozone Layer Recovers, Limiting Global Warming: UN Report
Ozone Layer Recovers, Limiting Global Warming: UN Report
A UN-backed scientific panel tasked with assessing the effects of the 1989 Montreal Protocol – an international agreement to phase out Ozone Depleting Substances – has found that the ozone layer continues to strengthen, and as a result, the earth will avoid 0.3 – 0.5°C of global warming by 2100.
Under the 1989 agreement, 99% of ozone-killing chemicals, including chlorofluorocarbons (CFCs) that once kept fridges cool, were banned due to a thinning of the ozone – also known as an ozone hole – above Antarctica.
In around four decades, the thinning of the Antarctic hole will be completely reversed, according to the report. The much smaller hole above the Arctic is expected to repair much sooner, DW reports.
By 2066, the Antarctic ozone hole is expected to reduce to its size in 1980, while the Arctic hole will do the same around 2045. Thinning around other areas of the globe should recover around 2040.
Beyond CFCs, ozone-eating chemicals including halons, methyl chloroform, carbon tetrachloride, hydrochlorofluorocarbons (HCFCs) and methyl bromide were once abundant in refrigerators, air conditioners, aerosols, solvents and pesticides.
These compounds attack ozone by releasing chlorine and bromine atoms that degrade ozone molecules in the stratosphere.
Since the substances were banned, declining concentrations of chlorine and bromine have helped to limit human exposure to harmful UV rays from the sun that can cause skin cancer, cataracts and suppress the immune system. -DW
“Thanks to a global agreement, humanity has averted a major health catastrophe due to ultraviolet radiation pouring through a massive hole in the ozone layer,” said UN Secretary-General Antonio Guterres last September 16, World Ozone Day.
Impacts on climate change?
Meanwhile, in a fringe benefit that won’t likely silence environmentalists, the panel affirmed the treaty’s positive impact on the climate.
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We Finally Know Where The Scandalous Ozone-Destroying Chemicals Are Really Coming From
We Finally Know Where The Scandalous Ozone-Destroying Chemicals Are Really Coming From
It’s been exactly one year since US scientists reported a mysterious surge in ozone-destroying chemicals, known as chlorofluorocarbons (CFCs).
Banned in 1987 under the globally signed Montreal Protocol, there was only one explanation: somewhere out there, in an unknown location, someone must have gone rogue, setting back progress on the ozone hole by a decade or more.
After much speculation, the whereabouts and magnitude of these harmful emissions has been confirmed in scientific research. As earlier reporting in The New York Times had already suggested, they seem to be coming from the northeast coast of mainland China.
Since the Montreal Protocol was declared a success in 2013, this highly industrial region has continued to emit, whether accidentally or not, CFC-11: the second most abundant chlorofluorocarbon in the atmosphere. Between the periods of 2008-2012 and 2014-2017, in fact, CFC-11 emissions increased here by roughly 110 percent.
“This increase accounts for a substantial fraction (at least 40 to 60 per cent) of the global rise in CFC-11 emissions,” an international team of researchers writes in a new report.
“We find no evidence for a significant increase in CFC-11 emissions from any other eastern Asian countries or other regions of the world where there are available data for the detection of regional emissions.”
These violations are likely going unreported because even though CFC-11 is illegal, it is also one of the cheapest ways to produce new foam insulation in refrigerators and buildings.
After tracking down documents and international sources, journalists at The New York Times and independent investigators discovered that in some factories in China, illegal CFC use has been slipping through the cracks for years.
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