Ozone layer 'is no longer disappearing and will return to full strength by 2048', says UN report



The ozone layer is no longer disappearing and could be back to full strength by the middle of this century, UN scientists have confirmed.

The phasing out of nearly 100 substances once used in products like refrigerators and aerosols has stopped the ozone layer being depleted further, although it is not yet increasing, according to a new United Nations report released last week.



And it claimed that international efforts to protect the ozone layer has averted millions of cases of skin cancer worldwide.

The ozone layer over Antarctica in September 1980, left, and how it looked this weekend. The dark blue indicates extremely low levels of ozone. Scientists expect it to return to pre-1980 levels by 2073



The ozone layer outside the polar regions is projected to recover to pre-1980 levels by 2048, although the annual springtime ozone hole over the Antarctic is not expected to recover until 2073.

Ozone in the stratosphere is important because it absorbs some of the Sun’s dangerous ultraviolet radiation.



A chart showing how ozone levels are expected to rise over the next 40 years

The report, published jointly by UNEP and the UN World Meteorological Organization (WMO) is the first comprehensive update in four years on the Vienna Convention for the Protection of the Ozone Layer and the Montreal Protocol phasing out chemicals which accelerate both ozone layer damage and climate change.

'It (the Protocol) has protected the stratospheric ozone layer from much higher levels of depletion by phasing out production and consumption of ozone depleting substances,' said the report.

The report was written and reviewed by 300 scientists and launched on the UN International Day for the Preservation of the Ozone Layer.

Given that many substances that deplete the ozone layer are also potent greenhouse gases, the Montreal Protocol ‘provided substantial co-benefits by reducing climate change,’ it added.

In 2010, reductions of ozone-depleting substances as a result of the Protocol, were five times larger than those targeted by the Kyoto Protocol, the greenhouse emissions reduction treaty.

'Without the Montreal Protocol and its associated Vienna Convention atmospheric levels of ozone-depleting substances could have increased tenfold by 2050,' Mr Steiner said.