Ozone layer(臭氧层) '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(确认).
The phasing out of nearly 100 substances(物质) 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 outside the polar regions is projected to recover to pre-1980 levels by 2048, although the annual springtime ozone hole over the Antarctic(南极地区) is not expected to recover until 2073.
Ozone in the stratosphere is important because it absorbs some of the Sun’s dangerous ultraviolet radiation.
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.
'This in turn could have led to up to 20 million more cases of skin cancer and 130 million more cases of eye cataracts, not to speak of damage to human immune systems, wildlife and agriculture.'(本文由在线英语听力室整理编辑) |