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Ozone depletion          

Ozone depletion

The ozone layer will become dangerously thin in the very near future. We need to protect our skin from sunburn and wear sunglasses to stop ultraviolet radiation from damaging our eyes.

Ozone is a gas with a molecule comprising three oxygen atoms. Ozone can be found in the atmosphere at an altitude of up to 100 km, although the stratospheric ozone layer is concentrated at between 20 and 40 km above the Earth's surface. Its most important function is to protect plants, animals and humans from ultraviolet (UV) radiation.


Recent changes in stratospheric ozone

  • In 1985, scientists discovered that the ozone layer had begun to grow thinner. The thinning was particularly obvious over the Antarctic, where a hole had appeared in the ozone layer, leading to a dangerous rise in levels of UV radiation.
  • At mid-latitudes over Europe, the ozone layer has been depleted by 6 to 8 percent. Ground-based and satellite observations have shown a decrease in ozone during the winter in the Northern Hemisphere.


Damage to the ozone layer is caused by ozone-depleting substances (ODS), which are released as a result of human activities. These substances include:

  • Freons, which are used in cooling technologies and refrigerators;
  • halons, which are used in fire-extinguishers;
  • methyl bromide, which is used in agriculture to control pests; and
  • various solvents and pesticides.


These chemical compounds contain chlorine, bromine and fluorine and can remain in the atmosphere for between 50 and 1,500 years, depending on their composition. Once released into the atmosphere, ODS rise slowly and begin depleting the ozone layer on contact. One molecule of ODS causes the destruction of thousands of ozone molecules. The process may be slow and time-consuming, but the barrier that protects human beings and the environment against UV radiation is gradually being destroyed.


Consequences

  • In human beings, an increase in UV radiation can cause cancer, cataracts, sunburn, snow blindness, skin ageing and weakened immune systems, which may eventually mean that people have to consider living underground. Non-melanoma skin cancers are among the most common forms of cancer in humans, and a correlation with UV radiation has been established. Risk factors for skin cancer are fair skin; blue, green or hazel eyes; light-coloured hair; a tendency to burn rather than tan; a history of severe sunburn; a large number of moles or freckles; and a family history of skin cancer.
  • Fish supplies will drop sharply in the world's oceans. Plant growth will slow and crop yields will decrease. Many plants and animals will die. Penguins are particularly at risk, and UV radiation has been found to affect aquatic ecosystems by limiting the production of phytoplankton and causing damage during the early development stages of fish, shrimps, crabs and amphibians. Phytoplankton is the basis of the food chain in oceans. More than 30 percent of the animal protein consumed by human beings worldwide comes from the sea, with an even larger percentage in developing countries.
  • Even at current levels, UV radiation can also affect the growth of terrestrial plants. There are big differences in UV response among species. Plants have several mechanisms for repairing the effects of UV radiation and, to a certain extent, may be able to adapt to increased radiation levels.

Measures to restore the ozone layer

  • Negotiations have been initiated among scientists, the business sector, politicians, representatives of public organisations and the media. Important agreements have been adopted, such as the Vienna Convention for the Protection of the Ozone Layer and the Montreal Protocol on Substances that Deplete the Ozone Layer, the aim of which is to regulate, gradually decrease and ultimately eliminate the use of ODS. More than 160 countries have already signed these agreements.
  • In 1991, the most developed and wealthiest countries established the Global Environment Facility (GEF), an international financing mechanism to aid the efforts of developing countries. Measures taken include the restructuring of products previously based on ODS.
  • Within the framework of such international agreements, the production of ozone-friendly refrigerants to replace Freons and chlorofluorocarbons (CFCs) has begun. Several of the main industrial producers of ODS (e.g. manufacturers of household aerosols, household refrigeration equipment and furniture) have introduced alternative substances that are less harmful to the ozone layer.

Belarus supports the initiatives of the international community to protect the ozone layer and was among the first countries to sign the Vienna Convention, the Montreal Protocol, and other related agreements. In addition:

  • The National Research Centre for Ozonosphere Monitoring (NRCOZ) was established in the framework of the Belarusian State University (BSU) in 2003.
  • Monitoring of the dynamics of the ozonosphere over Belarus began in 1997 at the Minsk Ozone Measuring Station (later part of the NRCOZ). Data on ozone concentrations from 2006 are now freely available on the NRCOZ website (http://ozone.bsu.by/).
  • No ODS are manufactured in Belarus and there are ongoing efforts to reduce and eliminate the importing and use of ODS in the country.


Commitments at national level include:

  • the phased reduction and eventual elimination of ODS (e.g. the CFCs HCFC-22, HCFC-142b, HCFC-21, HCFC-141b and mixtures thereof) by 2020;
  • the compilation of an updated list of products containing ODS in accordance with amendments adopted by the parties to the Montreal Protocol and ratified by the Republic of Belarus;
  • the implementation of safer substitutes for ODS;
  • the establishment of a network of recycling stations for the collection, treatment and re-use of waste ODS to prevent their release into the environment;
  • the introduction of restrictions and bans on the handling of ODS according to the finalised list in the appended Montreal Protocol;
  • the licensing of exports and imports of ODS; and
  • ozone monitoring and reporting on the status of stratospheric and tropospheric ozone over the territory of Belarus to relevant international organisations, including the Secretariat of the Montreal Protocol and the United Nations Environment Programme (UNEP).


The consumption of ODS in Belarus is steadily declining: from 1,589 ozone depletion potential (ODP) tonnes in 1989, total consumption plummeted to around 14 ODP tonnes in 2008 and 10 ODP tonnes in 2011. The vast majority (95 percent) of ODS currently in use are refrigerants.

The country has established control over imports of ODS and products containing them. Ozone-depleting substances may be imported only on the basis of a one-time authorisation granted by the Ministry of Natural Resources and Environmental Protection. The handling of ODS is strictly limited to around 600 entities that have an appropriate licence.

On January 1, 2000, Belarus banned the importing and exporting of substances with high ozone depletion potential. The use of dangerous Freons decreased significantly due to new refrigeration technology and the transition to ozone-safe Freons.

The Law on Environmental Protection and the Law on Air Protection contain requirements for the reduction and eventual elimination of ODS consumption in Belarus. However, the primary piece of legislation for this purpose is the Law on the Protection of the Ozone Layer.

In 2010, the Ministry of Natural Resources and Environmental Protection joined UNEP's Informal Prior-Informed Consent (iPIC) initiative, a mechanism for the voluntary exchange of information on intended trade between countries in ODS. The initiative covers the issuing of licences for ODS.

Between 1997 and 2001, the World Bank supported the Ozone-Depleting Substances Phaseout Project in Belarus with a grant from the Global Environment Facility (GEF). The project aimed to train specialists; obtain equipment for the detection and identification of ODS; ensure the recycling, recovery and destruction of ODS; and make targeted investments in projects to phase out hydrochlorofluorocarbons (HCFCs) by replacing them with ozone-friendly substances and natural refrigerants in industry and agriculture.




In the coming two decades, despite all the measures that have been taken, the ozone layer will become critically thin. Although it is expected to recover gradually, the process will take around another four decades. During this period it will be very important for people to protect their skin from sunburn — especially in the summer — and to wear sunglasses that protect their eyes from ultraviolet radiation.

The World Health Organization recommends the following simple precautions:

  • Always keep infants under one year old in the shade.
  • Limit the amount of time children spend in the midday sun.
  • Cover up with protective clothing, a hat and sunglasses.
  • Apply a generous amount of broad-spectrum sunscreen with a sun protection factor (SPF) of 15 or more.
  • Avoid sunlamps and tanning parlours.
  • Remember to protect yourself from the sun whenever you are outdoors.


Consumer behaviour is very important. Whenever possible, choose products that do not cause damage to the ozone layer. Look for labels indicating that products are Freon free and CFC free.

The following sources provide further information about how Belarus is addressing the problem of ozone depletion: