Our directory of things of interest

University Directory

Volcanic eruptions enhance ozone loss

  • Written by  Chris Fitch
  • Published in Climate
Volcanic eruptions enhance ozone loss
28 Sep
2018
The ongoing recovery of the planet’s ozone layer is being significantly affected by volcanic eruptions

Thanks to the 1987 Montreal Protocol that banned the production of ozone-depleting chlorofluorocarbons (CFCs), global efforts to prevent the depletion of the planet’s ozone layer have been surprisingly successful. Although a full recovery isn’t expected until the middle of the century, the ozone layer is now gradually replenishing, and the infamous ozone hole above Antarctica is slowly closing. However, new evidence underlines how the world’s volcanoes are hindering humanity’s efforts.

‘It’s important to recognise that volcanoes do not themselves destroy ozone, but rather enhance human-caused ozone loss,’ explains Catherine Wilka, from the Department of Earth, Atmospheric, and Planetary Sciences at Massachusetts Institute of Technology. When a volcano erupts, she explains, sulphuric acid particles are released. These cause chlorine in the stratosphere – such as that released by CFCs – to convert into a form where it is capable of destroying ozone.

Wilka and colleagues used climate model simulations to calculate the extent to which major volcanic eruptions have affected the ozone layer. The eruption of Mount Pinatubo in the Philippines in 1991 is a standout example from 1979-1998, when the ejected particles significantly escalated ozone depletion. From 1999 onwards, eruptions haven’t further harmed the layer but they have slowed its recovery. This indicates that it will be during periods of minimal volcanic activity that the Protocol will have the most impact in significantly repairing the ozone layer.

‘We had a particularly quiet period from the mid 1990s to about 2004, and have had a few moderate size eruptions since then,’ recalls Wilka. ‘When we calculate ozone recovery trends since 1998, the recovery is flatter than it would be if we’d had a volcanically active period in the early 2000s and a quiet period right now. That doesn’t mean the ozone layer isn’t recovering: it means that the recovery due to decreasing stratospheric chlorine will take longer to emerge from the natural variability. However, it’s important to stress that the ozone layer will continue to recover throughout the 21st century as long as we adhere to the Montreal Protocol, regardless of volcanic eruptions.’

This was published in the October 2018 edition of Geographical magazine

geo line break v3

Free eBooks - Geographical Newsletter

Get the best of Geographical delivered straight to your inbox by signing up to our weekly newsletter and get a free collection of eBooks!

geo line break v3

Related items

NEVER MISS A STORY - Follow Geographical on Social

Want to stay up to date with breaking Geographical stories? Join the thousands following us on Twitter, Facebook and Instagram and stay informed about the world.

More articles in NATURE...

Geophoto

With guaranteed sunshine, bright blue skies and not a hint…

Oceans

A review of coral-saving methods is helping communities decide which…

Polar

A seven-year study of Patagonia’s ice sheets has revealed the…

Climate

The environmental impact of Bitcoin is higher than its virtual…

Geophoto

With a camera in everyone’s pocket, the once rarified world…

Climate

The idea of the Earth as a self-regulating, living organism…

Oceans

A temporary fishing ban has been imposed by the European…

Wildlife

A look at the contribution of hippos to the savannah…

Wildlife

The new app encourages young children to connect with the…

Energy

A type of panel has been invented that can generate…

Tectonics

In the 4th century BC, Aristotle proposed that earthquakes were…

Climate

The Chartered Institution of Water and Environmental Management pledges to achieve net…

Tectonics

Earthquakes from time immemorial have attracted the attention of the…

Tectonics

A planned kayaking expedition in Nepal took on a whole…

Tectonics

Scientists from Bristol University are working in conjunction with EDF…

Tectonics

In the 1930s, Charles Richter developed a simple scale for…

Tectonics

Researchers at Colombia University have answered a question that has…