Monday, 19 November, 2018

Ozone layer to recover in 50 years

A view of the Los Angeles skyline from 4th Street Bridge in 2016 A view of the Los Angeles skyline from 4th Street Bridge in 2016
Theresa Hayes | 09 November, 2018, 14:47

Actions taken by countries under the Montreal Protocol have led to the start of recovery for the stratospheric ozone layer and the healing of the ozone hole at Earth's south pole, finds a new UN-backed report released today.

The Protocol was in response to the revelation that chlorofluorocarbons (CFCs) and other ozone-depleting substances - used in aerosols, cooling and refrigeration systems, and many other items - were tearing a hole in the ozone layer and allowing risky ultraviolet radiation to flood through. Levels were found to be reduced in the 1980s, caused by chlorofluorocarbons (CFCs) and halons, gases used in spray cans, fridges and insulation.

Ozone is a layer that protects life on Earth from harmful layers of ultraviolet rays from the sun.

According to a scientific assessment released in a conference held in Quito in Ecuador on Monday, the result will be that by 2030, the upper layer of ozone will be completely rectified on the upper hemisphere and the Antarctic ozone hole should disappear by 2060.

Paul Newman of Nasa, joint chairman of... The worldwide agreement compelled the global community to begin the phasing out of ozone-depleting substances like chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), and halons. "We stopped that", Paul Newman, a NASA scientist and co-chairman of the new United Nations report, told the AP. "If ozone-depleting substances had continued to increase, we would have seen huge effects".

Montzka said if the source of the new emissions could be identified and contained, the damage to the ozone should be minor.

However, while most of the banned gases have been phased out, the report found at least one violation of the protocol: an unexpected increase in production and emissions of CFC-11 from eastern Asia since 2012.

A United Nations study has revealed that the ozone layer is slowly recovering, and is even expected to be fully repaired by the 2060s.

Erik Solheim, head of UN Environment, described the Montreal Protocol as "one of the most successful multilateral agreements in history".

"It shows that the ozone layer is under fix, and highlights areas that must be strengthened for it to be an equally successful platform to phase out HFCs to limit global warming", said Shikha Bhasin, programme lead, Council on Energy, Environment and Water (CEEW).

In 2019, the Montreal Protocol's strength will continue with the signing of the Kigali Amendment, an agreement that will ban the future use of climate-warming gases in air conditioners, refrigerators, and other consumer products.

So a healed ozone layer will worsen man-made climate change there a bit, Newman said.

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