Global warming is the observed century-scale rise in the average temperature of the Earth's climate system and its related effects. Multiple lines of scientific evidence show that the climate system is warming.

The current global average temperature is 0.85ºC higher than it was in the late 19th century. Each of the past three decades has been warmer than any preceding decade since records began in 1850.

The world's leading climate scientists think human activities are almost certainly the main cause of the warming observed since the middle of the 20th century.

An increase of 2°C compared to the temperature in pre-industrial times is seen by scientists as the threshold beyond which there is a much higher risk that dangerous and possibly catastrophic changes in the global environment will occur. For this reason, the international community has recognised the need to keep warming below 2°C.

EU legislation to protect the ozone layer is among the strictest and most advanced in the world. Europe has not only implemented what has been agreed under the Montreal Protocol on protecting the ozone layer but has often phased out dangerous substances faster than required.

The ozone layer in the upper atmosphere protects humans and other organisms against ultraviolet (UV) radiation from the sun. In the 1970s scientists discovered that certain man-made chemicals deplete the ozone layer, leading to an increased level of UV radiation reaching the Earth.

Overexposure to UV radiation carries a number of serious health risks for humans. It causes not only sunburn but also greater incidences of skin cancer and eye cataracts.

There are also serious impacts on biodiversity. For example, increased UV radiation reduces the levels of plankton in the oceans and subsequently diminishes fish stocks. It can also have adverse effects on plant growth, thus reducing agricultural productivity. A direct negative economic impact is the reduced lifespan of certain materials like plastics.

Gases that damage the ozone layer - ozone-depleting substances (ODS) - have been used in a wide range of industrial and consumer applications, mainly in refrigerators, air conditioners and fire extinguishers. They have also been used as aerosol propellants, solvents and blowing agents for insulation foams.

The main ODS being phased out under the Montreal Protocol are

  • chlorofluorocarbons (CFCs)
  • hydrochlorofluorocarbons (HCFCs)
  • halons
  • carbon tetrachloride and
  • methyl bromide.
Most man-made ODS are also very potent greenhouse gases. Some of them are up to 14 000 times stronger than carbon dioxide (CO2), the main greenhouse gas.

Eliminating these substances therefore also contributes significantly to the fight against climate change. The international phase-out of ODS has so far delayed the impact of climate change by 8-12 years.

On the other hand, phasing out ODS has led to a strong growth of other highly warming gases, such as the HFCs (hydrofluorocarbons). In 2016, Parties to the Montreal Protocol agreed to add HFCs to the list of controlled substances.

The international community established the Montreal Protocol on substances that deplete the ozone layer in 1987. Policies put in place by the EU and its Member States often go beyond the requirements of the Montreal Protocol.

Already by 2010, the EU had significantly reduced its consumption of the main ozone-depleting substances, 10 years ahead of its obligation under the Montreal Protocol.

Furthermore, the EU has put in place controls on uses of ozone-depleting substances that are not considered as consumption under the Montreal Protocol, such as the use of ODS as a feedstock in the chemical industry.

The EU has also gone beyond the requirements of the Protocol in banning the use of the toxic chemical methyl bromide for any kind of fumigation.

EU legislation has not only been very effective in controlling ozone-depleting substances but has also acted as a driver for the development of innovative technologies. These include

  • alternatives to methyl bromide
  • new blowing agents for insulation foam
  • CFC-free metered dose inhalers for the treatment of asthma, and
  • innovative non-halon fire-fighting systems, for example on ships and airplanes.
The global consumption of ODS has been reduced by some 98% since countries started taking action under the Montreal Protocol.

As a result, the atmospheric concentration of the most aggressive types of ODS is falling and the ozone layer is showing the first signs of recovery. Nevertheless, it is not expected to recover fully before the second half of this century.

Much remains to be done to ensure the continued recovery of the ozone layer and to reduce the impact of ODS on climate change.

Actions needed are:

  • Ensuring that the existing restrictions on ODS are properly implemented and worldwide use of ODS continues to be reduced;
  • Ensuring that ODS are replaced with climate-friendly alternatives;
  • Recovering ODS from existing equipment and buildings;
  • Preventing illegal trade in ODS;
  • Reducing use of ODS in applications that are not considered as consumption under the Montreal Protocol.

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