Global problems such as the hole in the ozone layer demand global solutions. By providing crucial evidence on ozone depletion and the substances responsible, researchers at the Department of Chemistry have helped tackle a global environmental threat.

Cambridge University, through these scientists, has had a huge impact on protecting the earth for future generations

Stephen Andersen, formerly US EPA and now IGSD

Working together

The Montreal Protocol – which banned the substances responsible for destroying the ozone layer – shows that global environmental problems can be tackled when politicians, scientists and industry work together.

Following the discovery of the ozone hole above Antarctica by scientists at British Antarctic Survey, Professor John Pyle and Dr Neil Harris in the Department of Chemistry have broadened and deepened our understanding of the ozone layer and the chemical processes driving its depletion.

Pyle and Harris’s research has helped inform amendments to the Montreal Protocol, and by modeling the decline and recovery of the ozone layer before and after the protocol’s introduction, their research has charted the effectiveness of this key international instrument.

In helping address a crucial global environmental problem, Pyle and Harris’s research has also contributed to human health, because a healthier ozone layer means that by 2030 there will be some two million fewer cases of skin cancer each year.

Global research

Since the 1980s, Pyle and Harris’s research has advanced our understanding of the ozone layer and the substances that destroyed it.

By collaborating in long-term, multinational studies, they have been at the heart of the global science required to address a global problem.

In 1989, the European Ozone Research Coordinating Unit was set up in the Department of Chemistry to coordinate atmospheric research across Europe. Since then, Pyle and Harris’s field experiments have taken them from the North Pole to the Equator.

Their research in the Arctic has complemented what was known about patterns of ozone depletion in the Antarctic. And as well as improving our understanding of the chemical reactions that drive seasonal ozone loss, Pyle and Harris have also discovered much about the links between ozone-depleting substances and ozone depletion itself.

After leading major international studies of ozone depletion in the Arctic, they worked on long-term, multinational projects using ground-based and satellite measurements to investigate ozone trends in the Northern Hemisphere.

More recently, Pyle and Harris modeled the effect of climate change on delivery of ozone- depleting substances to the ozone layer, and measured natural halo-carbons in the tropics, the importance of which is increasing now that levels of man-made halo-carbons have fallen following the Montreal Protocol.

Their studies provided the evidence that the UK government used to strengthen the Montreal Protocol, and to accelerate the phase out at European level of hydro-fluorocarbons, chemicals that do not deplete ozone but which are potent greenhouse gases.

Pyle and Harris have made major contributions to international assessments of the state of the ozone layer, mandated every four years under the Montreal Protocol and the route by which scientific understanding is feed into the policy arena. Pyle is one of four international co-chairs of the Science Assessment Panel, charged with the production of the assessments; he and Harris have frequently been lead authors in the assessment.

Ongoing impact

By contributing to the science underpinning the Montreal Protocol, Pyle and Harris’s research will continue to contribute to healing the ozone layer for decades to come, bene ting human health and the health of the planet.