The Melbourne Doughnut
Explore how well Melbourne is tracking as a place that supports people and planet to thrive.
Ozone Layer Depletion
Earth’s stratospheric ozone layer filters out ultraviolet (UV) radiation from the sun, protecting life on earth. Some human-made chemical substances, such as chlorofluorocarbons (CFCs) will, if released, enter the stratosphere and deplete the ozone layer, exposing Earth and her inhabitants to the sun’s harmful UV rays.
Contributors to Ozone Layer Depletion
The appearance of a “hole” in the ozone layer is an example of an Earth-system threshold being crossed. Any thinning of the ozone layer has negative impacts on marine organisms and poses risks to human health. Most ozone-depleting substances have been phased out through international agreement. Some substances are still in use because effective alternatives have not been identified; these include:
- Methyl bromide, used as a fumigant in quarantine settings
- Halon, used to suppress fires in contained environments such as airplanes and submarines
Planetary Quotas for Greater Melbourne
Each dimension of the Ecological Ceiling is measured using per-capita Planetary Quotas for Greater Melbourne.
Ozone-depleting Substances
Chemical substances that weaken the ozone layer are increasing harmful UV exposure
| What we're measuring | Greater Melbourne Quotas | Now |
|---|---|---|
Montreal gas emissions (measured in Ozone Depleting Potential) | Under 9.58 tonnes ODP per year | 1.37 tonnes ODP per year |
Placing Ozone Layer Depletion in the system
Global to local connections
The ozone layer is an example of the power of global collaboration. After decades of releasing vast amounts of ozone-depleting substances into the stratosphere, current trends suggest that the Montreal Protocol - a global agreement to phase out the use of ozone depleting substances - has put us on track to repair the ozone layer, returning to pre-1980 levels by 2065. Australia has been especially exposed to the thinning of the ozone layer due to our latitude, and therefore has a significant amount to gain from repair as a result of phasing out ozone-depleting substances. This offers a strong example of localised impacts from global action, and a critical motivator for Australia to adhere to global protocols for minimising use of substances that are harmful to the ozone layer.
Learn more
How was this dimension developed?
The Ozone Layer Depletion dimension of the Greater Melbourne City Portrait has been developed in collaboration with Open Corridor with research support from the University of Melbourne. The assessment of Melbourne's environmental footprint applies a Planetary Accounting approach. A detailed description of the City Portrait methodology is outlined in the About section of the website.
Where can I access the data?
Data for Ozone Layer Depletion, along with the other Ecological Ceiling dimensions are available in the Ecological Ceiling Dataset.
For Social Foundation dimensions, see the Social Foundations Dataset.
Where can I find more information on Ozone Layer Depletion in a regenerative Melbourne?
The City Portrait is informed by extensive research and resources on Doughnut Economics and related frameworks, as well as sector-specific research associated with each dimension. More detailed research that has informed the Ozone Layer Depletion dimension is available to explore via Altiorem's library.
How can I get involved?
To get involved with ongoing development of the City Portrait or learn more about Regen Melbourne, email alison@regen.melbourne