CFC Ban And The Nightmare Of A "World Avoided"
© NASA’s Goddard Space Flight Center Scientific Visualization Studio.
How the depletion of the ozone layer might have looked without the Montreal Protocol - dark blue represents lower ozone concentrations
Without the global CFC ban we would already be facing the reality of a ‘scorched earth’, according to researchers measuring the impact of the Montreal Protocol.
The Montreal Protocol on Substances that Deplete the Ozone Layer bans chemicals such as chlorofluorocarbons.
Without the treaty, Earth and its flora would have been exposed to far more of the Sun's ultraviolet (UV) radiation.
The research team, led by Dr. Paul Young of Lancaster University, reveals that if ozone-destroying chemicals, which most notoriously include CFCs, had been left unchecked then their continued and increased use would have contributed to global air temperatures rising by an additional 2.5°C by the end of this century. A worldwide ban on ozone-depleting chemicals in 1987 has averted a climate catastrophe today, scientists say.
Their new evidence reveals the planet’s critical ability to absorb carbon from the atmosphere could have been massively degraded sending global temperatures soaring if we still used ozone-destroying chemicals such as CFCs.
Our new modelling tools have allowed us to investigate the scorched Earth that could have resulted without the Montreal Protocol's ban on ozone depleting substances.
Dr Paul Young
Former UN Secretary General Kofi Annan has called it "perhaps the single most successful international agreement".
New modelling by the international team of scientists from the UK, USA and New Zealand, published today in Nature
, paints a dramatic vision of a scorched a "World Avoided".
The modelling reveals
Continued growth in CFCs would have led to a worldwide collapse in the ozone layer by the 2040s.
By 2100 there would have been 60 per cent less ozone above the tropics. This depletion above the tropics would have been worse than was ever observed in the hole that formed above the Antarctic.
By 2050 the strength of the UV from the sun in the mid-latitudes, which includes most of Europe including the UK, the United States and central Asia, would be stronger than the present day tropics.
This study highlights the link between two major environmental concerns – the hole in the ozone layer and global warming - and the subject of the major international conference in Glasgow (COP26) starting 31st October this year.