The ozone layer in the Earth’s stratosphere absorbs most of the Sun’s ultraviolet radiation which could otherwise potentially damage exposed life forms near the surface. The thickness of the ozone layer varies from one region to another. It is mainly found in the lower region of the stratosphere, from approximately 15 to 35 km above Earth’s surface.
Research in the year 1976 showed that the ozone layer was being depleted owing to the use of chlorofluorocarbons (CFCs) released by the chemical industry. The dangers of being exposed to the Sun’s harmful UV rays include skin cancer and the extinction of other life forms. This research led to the ban of harmful chemicals to protect the ozone layer.
The ban and controlled use of ozone depleting substances and the related reductions have not only helped protect the ozone layer for this and future generations, but have also contributed significantly to global efforts to address climate change; furthermore, it has protected human health and ecosystems by limiting the harmful ultraviolet radiation from reaching the earth
History of International Day for the Preservation of the Ozone Layer
The scientific confirmation of the depletion of the ozone layer prompted the international community to establish a mechanism for cooperation to take action to protect the ozone layer. This was formalised in the Vienna Convention for the Protection of the Ozone Layer, which was adopted and signed by 28 countries, on 22 March 1985. In September 1987, this led to the drafting of The Montreal Protocol on Substances that Deplete the Ozone Layer.
The aim of the Montreal Protocol is to protect the ozone layer by taking measures to control total global production and consumption of substances that deplete it on the basis of developments in scientific knowledge and technological information. On 16th September 2009, the Vienna Convention and the Montreal Protocol became the first treaties in the history of the United Nations to achieve universal ratification. The day was first celebrated on September 16, 1995.
Ozone Day Theme: 32 years and healing
The theme for this year celebrates over three decades of remarkable international cooperation to protect the ozone layer and the climate under the Montreal Protocol.
The Montreal Protocol has led to the phase-out of 99 per cent of ozone-depleting chemicals in refrigerators, air-conditioners and many other products. The latest Scientific Assessment of Ozone Depletion completed in 2018, shows that, as a result, parts of the ozone layer have recovered at a rate of 1-3% per decade since 2000. At projected rates, Northern Hemisphere and mid-latitude ozone will heal completely by the 2030s. The Southern Hemisphere will follow in the 2050s and Polar Regions by 2060. Ozone layer protection efforts have also contributed to the fight against climate change by averting an estimated 135 billion tonnes of carbon dioxide equivalent emissions, from 1990 to 2010.