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Asia Pacific Regional Ozone2Climate Art Contest

Is Ozone Layer Depletion still an issue?

The stratospheric ozone layer is vital for life on Earth. Stratospheric ozone is considered good for humans and other life forms because it absorbs ultraviolet (UV) radiation from the Sun, preventing it from reaching the planet's surface. If not absorbed, high energy UV radiation, UV-B, would reach Earth’s surface in amounts that are harmful to a variety of life forms.

What are Ozone Depleting Substances?

Ozone-depleting substances (ODS) are chemical compounds that consist of carbon, hydrogen, chlorine and/or bromine. They are known as halocarbons. Halocarbons in the atmosphere actually contribute to both ozone depletion and climate change. They are very stable, and do not break down in the lower atmosphere (troposphere). This allows the compounds to reach the stratosphere and remain there for up to 120 years.

How do Vienna Convention and Montreal Protocol help Ozone layer and Climate protection?

The 1985 Vienna Convention is the international community agreed to establish a framework to protect the ozone layer. The Vienna Convention showed the commitment of the country parties to protect human health and the environment from the effects of ozone depletion through research, observation and exchange of information.

The 1987 Montreal Protocol mandated that country parties take action to limit the production and consumption of ozone-depleting substances (ODS). Initially, the Montreal Protocol regulated only certain types of ODS, which consisted of five types of chlorofluorocarbons (CFCs) and three types of halon gases. With new technologies new research, the number of controlled substances increased through several amendments.

Learn more from Booklet of ‘Protect the Ozone Layer and the Climate’, UNEP, 2021.

How is Ozone Layer Depletion related to Climate Change?

Ozone depletion and global climate change are linked because ozone, ozone-depleting substances and their substitutes are greenhouse gases (GHGs), therefore lead to Earth’s surface warming.

The GHGs in Earth’s atmosphere absorb outgoing infrared radiation, trapping heat in the atmosphere and warming the surface. The most important natural GHG is water vapor. Without this natural greenhouse effect, Earth’s surface would be much colder than current conditions.

Impacts of Ozone Layer Depletion and Climate Change

Ozone layer depletion causes levels of UV-B radiation to increase on the Earth's surface while global warming caused by greenhouse gases is heating the temperature of Earth. Both ozone layer depletion and global warming endanger the health of species and ecosystems.

What I can do to protect ozone layer and climate under Montreal Protocol?

Choose environmentally friendly refrigerators and air conditioning appliances that do not rely on ODS or high-GWP refrigerants, if in doubt ask your trusted retailer.

Choose appliances with high energy efficiency (in some countries you can rely on the energy labels to understand efficiency), if in doubt ask your trusted retailer.

Carry out periodical maintenance to clean the systems.

Rely only on properly certified/trained servicing technicians (in some countries certification schemes are enforced).

Learn more about how your action matters from Booklet of ‘Protect the Ozone Layer and the Climate’, UNEP, 2021. and Ozone Secretariat website ‘what you can do’

Download Ozone Booklet
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