Ozone depleting substances that are regulated in New Zealand and measures to reduce them. Show
On this pageOzone depleting substances are man-made gases that destroy ozone once they reach the ozone layer. The ozone layer sits in the upper atmosphere and reduces the amount of harmful ultra violet radiation that reaches Earth from the sun. Ultraviolet radiation can have detrimental effects on both humans and the environment. For instance inducing skin cancer and cataracts, distorting plant growth and damaging the marine environment. Ozone depleting substances include:
They have been used as:
Chlorofluorocarbons (CFCs) were widely used as refrigerants until the 1980s when it was confirmed that they were the main source of harm to the ozone layer. They are also considered greenhouse gases that cause climate change. CFCs have not been imported into New Zealand since 1996. However there are still CFCs left in older industrial air conditioning and refrigeration systems, car air conditioning systems and domestic refrigerators. Hydrochlorofluorocarbons (HCFCs) have been used as a substitute for CFCs. They do less damage to the ozone layer than CFCs. New Zealand phased out imports of HCFCs in 2015. Halons are halocarbon gases that were originally developed for use in fire extinguishers. Production and consumption of halons ended in 1994 in developed countries including New Zealand. Halons produced before 1994 and recycled halons are now the only sources of supply in New Zealand. The Fire Protection Association of New Zealand undertook a halon responsible disposal project. Find out more on the Fire Protection Association of New Zealand website. Methyl bromide is an ozone depleting substance and toxic to humans. The use of methyl bromide in New Zealand is only permitted for quarantine and pre-shipment purposes. Find out more about Methyl bromide. It is illegal to dispose of ozone depleting substances by releasing them into the atmosphere. Unwanted ozone depleting substances should be collected for destruction. The Environmental Protection Authority is responsible for issuing permits to import or export ozone depleting substances. Hazardous aspects of ozone depleting substances are controlled by the Hazardous Substances and New Organisms Act 1996. Controls on ozone-depleting substances [Environmental Protection Authority website] Hazardous Substances and New Organisms Act 1996 [New Zealand Legislation website]. Hydrofluorocarbons (HFCs) have been used since the early 1990s as an alternative to CFCs and HCFCs. HFCs do not contribute to ozone depletion, but they are potent greenhouse gases. In 2016, New Zealand adopted the Kigali Amendment to the Montreal Protocol to phase down HFCs worldwide. New Zealand has completed the domestic processes required to meet the Amendment’s obligations, and will ratify it on 3 October 2019 so it enters into force on 1 January 2020. For more information see Hydrofluorocarbons phase-down. Page Last modified 09 Aug 2021 Forty years ago, scientists warned that a hole in the layer of ozone surrounding the earth could have serious effects on human health and the environment. This problem is being solved thanks to a global agreement to stop the use of ozone-depleting chemicals that damage the ozone layer. But now scientists are concerned that the substances used to replace these ozone-depleting chemicals are acting to trap heat inside the earth, exacerbating the greenhouse effect. Can policymakers protect the ozone layer while also helping prevent climate change? Many aerosol propellents contained CFCs before international agreements limited their use. Image © Scott Witt What is the ozone layer and how was it damaged?The ozone layer sits in the stratosphere between 15 km and 30 km above the earth. It absorbs most of the sun's ultraviolet radiation (UV-B), limiting the amount of this radiation that reaches the surface of the Earth. Because this radiation causes skin cancer and cataracts, the ozone layer plays an important role in protecting human health. It also prevents radiation damage to plants, animals, and materials. In the 1970s, scientists noticed that the ozone layer was thinning. Researchers found evidence that linked the depletion of the ozone layer to the presence of chlorofluorocarbons (CFCs) and other halogen-source gases in the stratosphere. Ozone-depleting substances (ODS) are synthetic chemicals, which were used around the world in a wide range of industrial and consumer applications. The main uses of these substances were in refrigeration and air conditioning equipment and in fire extinguishers. Other important uses included aerosol propellants, solvents and blowing agents for insulation foams.  Ozone depletion (blue colours) in the South hemisphere in 2006.Source: National Aeronautics and Space Administration (NASA) - Goddard Space Flight Center International action has been effective in protecting the ozone layerTo halt the depletion of the ozone layer, countries around the world agreed to stop using ozone-depleting substances. This agreement was formalised in the Vienna Convention for the Protection of the Ozone Layer in 1985 and the Montreal Protocol on Substances that Deplete the Ozone Layer in 1987. In 2009, the Vienna Convention and the Montreal Protocol became the first treaties in the history of the United Nations to achieve universal ratification. Substances covered by the protocol are referred to as 'controlled substances'. The main substances include chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), halons, carbon tetrachloride, methyl chloroform and methyl bromide. The damage to the ozone layer caused by each of these substances is expressed as their ozone depletion potential (ODP). Figure 1: Consumption of controlled ozone-depleting substances
These international agreements helped to greatly reduce the worldwide use of ozone-depleting substances in Europe and around the World (Figure 1). Scientific monitoring shows signs that the ozone layer is starting to recover. Full recovery is not expected to occur before the middle of the 21st century. Protecting the ozone layer also protects the climateThe reduction in ozone-depleting substances has also had a beneficial side-effect. Ozone-depleting substances are also very potent greenhouse gases, contributing to the phenomenon as other substances widely known to have a greenhouse effect like carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). Therefore, by reducing emissions of ozone-depleting substances, the Montreal Protocol has protected both the ozone layer and the climate at the same time. The magnitude of this benefit is substantial. The reduction in ODS emissions expected as a result of compliance with the Montreal Protocol has been estimated globally at 10-12 giga-tonnes of CO2-equivalent between 1985 and 2010 (Velders et al. 2007). In contrast, the reduction target of greenhouse gas emissions under the Kyoto Protocol (assuming full compliance by all developed countries) is estimated at 1-2 giga-tonnes of CO2-equivalent on average per year between 2008 and 2012, compared to base-year emissions. The phasing out of climate-changing ODS under the Montreal Protocol has therefore avoided greenhouse gas emissions by an amount 5-6 times larger than the target of the Kyoto Protocol for 2008-2012. ODS substitutes are now raising concernsThe reduction of ODS emissions is not a uniformly positive story. In fact it has indirectly led to new problems. Fluorinated gases (F-gases) have been introduced as substitutes for ODS in many sectors such as refrigeration and air conditioning applications. F-gases include hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulphur hexafluoride (SF6). These gases do not deplete the ozone layer, but they are greenhouse gases. This means that these new gases also contribute to climate change. And to make matters worse, these F-gases often have a far larger impact on the climate than 'traditional' greenhouse gases such as carbon dioxide (CO2). For example, some F-gases have a greenhouse effect that is up to 23 000 times more powerful than the same amount of carbon dioxide. Fortunately, the emissions of F-gases are far smaller than those of CO2, but the use of F-gases and their presence in the atmosphere have increased since the 1990s. As a result, the significant contribution of the Montreal Protocol to fighting climate change is in danger of being wiped out by the growing importance of F-gas emissions. Global and European agreements to limit F-gasesF-gas emissions are monitored under the United Nations Framework Convention on Climate Change (UNFCCC) and its Kyoto Protocol, but not currently addressed by the Montreal Protocol. Fluorinated gases presently account for about 2% of global greenhouse gas emissions. Several countries have started to take measures on F-gases, led by the European Union (EU) which has committed to reducing use of HFCs, the most important F-gases, by 80% of today's levels by 2030. There are two approaches to reducing F-gas emissions. The first approach is to avoid the use of F-gases completely by using gases or technologies that are less damaging to the climate. The second approach is to reduce the use of F-gases in products and equipment. The EU first set out specific policies to reduce F-gas emissions in 2006 with the so-called 2006 F-gas Regulation, and with a directive limiting F-gases used in air conditioners in cars, the so-called MAC Directive. In the absence of this legislation, F-gas emissions were projected to increase (Figure 2, orange line). A revised 2014 F-gas Regulation was adopted in 2014 which will lead to significant additional savings (figure 2, blue line) due largely to the following new measures:
These new measures will lead to savings of 70 Mt CO2 eq per year, or two-thirds of 2013`s emissions, by 2030. Expected total cumulative avoided emissions are estimated to be 1.5 Gt CO2 by 2030 and 5 Gt CO2 by 2050.
Figure 2: Projected evolution of F-gas emissions from all emission sources in the EU-27 in 1995-2050 in the scenario “without measures” (i.e. without EU F-gas policies), the scenario “with measures” (i.e. initial EU F-gas policy) and additional measures (i.e. the new F-gas policy).Considering overall emissionsBecause F-gases contribute to climate change, businesses are now looking to replace them with other substances. Alternatives that do not damage the ozone layer or contribute to climate change have become available over recent years in a variety of applications such as refrigeration, air conditioning, foam blowing and aerosols. Many of these alternatives lead also to higher energy efficiency which is important as the indirect emissions from energy use during the lifespan of a product are often considerably higher than direct emissions of F-gases. Further work needs to be done to reduce HFCs and ODSHFCs account for 98% of F-gas emissions, and their use continues to increase even though environmentally-friendly alternatives to HFCs exist. Measures that further limit the use and emissions of HFCs are therefore needed. Within the EU, ensuring a full implementation of the new F-gas Regulation (and in particular the phasing down of HFCs that it envisages) is critically important. And even though most ODS are being phased out, the Montreal Protocol still allows some quantities of ODS to be produced and used for certain niche applications (e.g. feedstock use). Cost-effective alternatives in these niche applications should be developed. In addition, large quantities of ODS are still contained in old equipment (refrigeration systems and air conditioners) and buildings (foams) and will be released in to the atmosphere if not properly reclaimed and destroyed. Measures enabling the safe recovery of remaining ODS are therefore also essential. Further informationThe EEA supports the European Commission and Member States in the annual company-based reporting of information concerning the production and use of ODS and F-gases in the European Union. The reported information is summarised in the following annual reports by the EEA:
The EEA also publishes two related indicators:
PermalinksGeographic coverageAustria Belgium Bulgaria Croatia Cyprus Czechia Denmark Estonia Finland France Germany Greece Hungary Iceland Ireland Italy Latvia Liechtenstein Lithuania Luxembourg Malta Netherlands Norway Poland Portugal Romania Slovakia Slovenia Spain Sweden Switzerland Turkey United Kingdom TopicsTagsWhat are the effects of ozone layer depletion on the environment?Stratospheric ozone depletion leads to an increase in UV -B that reach the earth's surface, where it can disrupt biological processes and damage a number of materials. The fact that UV -B can cause biological effects is well demonstrated by the familiar sunburn that follows overexposure to the sun.
What causes ozone depletion?Ozone depletion occurs when chlorofluorocarbons (CFCs) and halons—gases formerly found in aerosol spray cans and refrigerants—are released into the atmosphere (see details below).
Does ozone depletion cause global warming?Ozone depletion and climate change are linked in a number of ways, but ozone depletion is not a major cause of climate change. Atmospheric ozone has two effects on the temperature balance of the Earth. It absorbs solar ultraviolet radiation, which heats the stratosphere.
Which of the following is an important contributor to both global warming and ozone depletion *?The chlorofluorocarbons are the compounds responsible for BOTH ozone depletion and contribution to the greenhouse effect.
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The main environmental effects of ozone depletion could include all of the following EXCEPT
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