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Research | Polar research | Antarctic research - Ozone depletion
Ozone depletion, a problem common to Finland and Argentina
The discovery of Antarctic ozone depletion and the role of freons in the depletion resulted in the 1987 Montreal Protocol. In turn, the Protocol led to reductions in emissions of freon compounds. Thereafter, the production and consumption of other ozone-depleting substances have also been reduced. Amendments to the Montreal Protocol have been made several times, the most recent being the Beijing amendment in 1999. The Montreal Protocol may be regarded as a success story of international environment policy. The international communit was able to agree on quick and considerable reductions in the production and consumption of halogenated compounds soon after the discovery of Antarctic ozone depletion.
Both Finland and Argentina have experienced enhanced springtime UV radiation doses due to ozone depletion in both hemispheres. Since 1987 Finland and Argentina have collaborated productively in investigating atmospheric ozone and solar UV radiation.
Ozone is essential for life on the Earth's surface because of its ability to absorb solar UV-B radiation, which is hazardous to living organisms. Without ozone in the atmosphere life would be possible only under water. UV-B radiation causes skin cancers and cataracts, affects the human immune system and leads to ageing of skin. UV radiation also affects vegetation and aquatic ecosystems. The latter effects have been reported as a result of ozone depletion over the Antarctic sea area.
Ozone depletion at high latitudes is one of the most obvious global environmental problems caused by anthropogenic emissions. The observation of low total ozone columns over Antarctica greatly surprised the scientific community. Explanations for the low ozone columns included, e.g. changes in solar activity or in the large-scale circulation patterns in the atmosphere. Freons were also proposed as a cause, although the existing theories did not support this. The observed low total ozone columns over Antarctica were eliminated from the satellite records as erroneous data.
At the same time with the formulation of a new theory, a large international Antarctic research study was carried out in 1987. The study suggested that chlorine originating from freons was the cause of the detected massive ozone destruction. Outside the polar regions free chlorine is captured by nitrogen oxides, preventing large-scale chlorine catalysed ozone destruction. However, in the polar winter and spring atmospheres, polar stratospheric clouds serve as surfaces for capturing free nitrogen oxides from the atmosphere and lead to release of chlorine from reservoirs. Cold temperatures, below -78 ° C, are needed for the formation of polar stratospheric clouds. Cold airmasses are found inside large-scale low-pressure areas in winter polar stratospheres, inside so-called polar vortices.
The stratosphere contains 90% of the atmospheric ozone, and the remaining 10% is in the lower atmosphere, the troposphere. In the troposphere, high concentrations of ozone may negatively affect human health, forests and agriculture. The lower atmospheric ozone concentrations have been increasing in many parts of the world due to enhanced emissions of nitrogen oxides, hydrocarbons and carbon monoxide. These emissions are mainly originating from traffic, energy production and from biomass burning. Both stratospheric and tropospheric ozone have an effect on climate, because of the infrared and ultraviolet radiation absorption properties of ozone.
Learn more about ozone science from the "Executive summary of Scientific Assessment of Ozone Depletion: 2002" published by the Ozone Secretariat of UNEP/WMO or take the Ozone Hole Tour of the University of Cambridge.
From a global perspective, the greatest ozone depletion has been observed at the high latitudes of both hemispheres. Over Antarctica the largest springtime total ozone deficiency has exceeded 70%, whereas at the northern high latitudes the deficiency has been about half of that. The depleted ozone airmass of Antarctica has occasionally moved over inhabited areas of southern Argentina and Chile. In the Northern Hemisphere, ozone depletion has been typically observed over Northern Europe including Finland. Ozone depletion has led to enhanced UV radiation.
The national meteorological institutes in Finland (FMI) and Argentina (SMN) started a joint ozone research programme in 1987, including total ozone measurements over Marambio, Antarctica and Sodankylä, Finland. In 1988 routine ozone soundings using Finnish Vaisala ozone-sounding equipment were started at Marambio and at Sodankylä. Also satellite data, atmospheric chemistry-dynamics models, radiative transfer models and meteorological analysis data have been used in the research programme. In 1999 and 2003 the Marambio activities formed an important part of the international stratospheric ozone research campaign, first in APE-GAIA and then in QUOBI.
Under the World Climate Research Programme, the SPARC Programme (Stratospheric Processes and their Role in Climate) has been established, with the aim of studying the climatic relationship between the stratosphere, the troposphere and the ozone layer. In Argentina, scientists from various fields, belonging in particular to CONICET and the University of Buenos Aires, established the middle atmosphere group in 1998 to carry out research activities in this field. Cooling of the lower stratosphere has been observed, and its connection to lower atmospheric climate change is theorised. Other results show that in recent years there has been an extension of the low ozone values over Antarctica well up to February. These results also show that the ozone hole has a tendency to locate itself close to the South Cone of South America, and subsequently also over mainland Chile and Argentina.
Antarctic ozone depletion has intensified considerably since its discovery in the early 1980s. Ozone depletion has also been observed at high northern latitudes during the 1990s; a strong loss has been measured during most of the last thirteen springs. In the Arctic, the polar vortex is typically warmer and less stable than its Antarctic counterpart.
The Antarctic polar vortex is, on the contrary, cold and stable enough every year to lead to massive springtime ozone destruction. Over Antarctica, ozone depletion has during the last eight years reached a state where almost all ozone in the altitude range of 15-20 km in the lower stratosphere has been depleted. The area of depleted airmasses has also become larger. The year 2002 was an exception due to particular meteorological conditions that lead the polar vortex to dissolve very early, which halted the chemical depletion process.
In 1999 the Finnish-Argentine scientific collaboration was extended to include also UV radiation research. As a joint effort of Argentina, Spain and Finland a network for monitoring the spectral distribution of UV and photosynthetically active radiation was established. The network consists of instruments located at Marambio and Belgrano on Antarctica and at Ushuaia, as well as a calibration system.
During 2003 FMI and SMN will start measurements with two new aerosol research instruments.
The results of Antarctic and Arctic ozone research have been published in several articles in international journals, as academic theses and in publications for the public. The generated datasets have also been important for the annual reports of the World Meteorological Organization dealing with the state of ozone depletion. The material is also essential for the work of the international scientific community and is distributed through the World Ozone Data Centre.
Global efforts to protect the ozone layer are based on two international instruments. The Vienna Convention 1985 provides for scientific and technical co-operation, and it laid the groundwork for the Montreal Protocol.
The Montreal Protocol on Substances that Deplete the Ozone Layer was adopted by governments in 1987. It has been modified four times to include an increasing number of ozone-depleting substances, to strengthen the phase out schedules and to improve effective implementation of its provisions. The amendments were adopted in London (1990), Copenhagen (1992), Montreal (1997) and Beijing (1999). The Protocol aims to reduce and eventually eliminate the emissions of man-made ozone-depleting substances. In 2003 there were 184 parties to the Protocol.
The Montreal Protocol is successful because of regular revision of the requirements on the basis of the latest scientific and technical information provided by the assessment panels. This has enabled the Parties to react quickly to the new information with policy measures.
The Protocol's underlying principle is common but differentiated responsibility between developed countries and developing countries. An important part of the Protocol is the Multilateral Fund, the financing mechanism which assists developing countries in meeting their requirements.
Industrialised countries have phased out the production and consumption of CFCs, halons, methyl chloroform, carbon tetrachloride and HBFCs, and phase out dates have been agreed for the remaining controlled substances, HCFCs and methyl bromide. Developing countries generally have a 10-year grace period beyond the phase out dates for industrialised countries. Certain productions or uses are exempted from the phase out requirement, such as essential and critical uses and production for basic domestic needs of developing countries.
Read more about the Montreal Protocol from the web site of the Ozone Secretariat of UNEP/WMO.
Finland
Finland became a Party to the Vienna Convention in 1986 and to the Montreal Protocol in 1988. Finland has also ratified the London and Copenhagen amendments to the Protocol.
The provisions of the Montreal Protocol are implemented in the European Community by way of a regulation. The new EC regulation will apply from 1 October 2000; after that Finland as well as the EC will finalize the ratification of the Montreal and Beijing amendments to the Montreal Protocol.
Finland hosted the First Meeting of the Parties to the Montreal Protocol in 1989. The Government of Finland established the Finnish Trust Fund in 1991 to assist non-Party developing countries with the objective of facilitating and expediting their joining of the Montreal Protocol. All of the 20 countries assisted under the fund through the UNEP Ozone Action Programme have not only become Parties to the Montreal Protocol, but have also expedited their implementation of control measures.
As a supplement to the EC regulation, Finnish national legislation also regulates ozone-depleting substances. These instruments together provide a comprehensive control of ozone-depleting substances. Production, placing on the market, use and export of ozone-depleting substances or equipment containing them is forbidden, with the exception of essential and critical uses and of HCFCs used for servicing of existing refrigeration equipment until 2015. Finland has never produced ozone-depleting substances and its consumption of them has been relatively small. The use has decreased from 2600 ODP-tonnes (metric tonnes multiplied by ozone-depleting potentials) in 1990 to 80 ODP-tonnes in 1998.
Argentina
Argentina became a Party to both the Vienna Convention and the Montreal Protocol in 1990. Argentina has also ratified the London and Copenhagen amendments to the Protocol.
The country programme of the Argentine Government for the protection of the ozone layer was submitted and approved in 1994. This programme contains the policies of the Government and industry to reduce and phase out the consumption of ozone-depleting substances (ODS). The aim is to reduce and eliminate the consumption of CFCs and halons by the year 2006.
To carry out the government institutional action plan, the National Ozone Unit was formed in 1996, and the halon and methyl bromide consultative groups were established in 1998 and 1999, respectively.
Argentina will comply with the first control measure established by the Montreal Protocol. Under the Protocol requirements the country's consumption of CFCs and halons should be frozen at 4697 ODP-tonnes; Argentina's consumption in 1999 was 4316 ODP-tonnes.
Since 1991, the establishment of new CFC manufacturing plants has been prohibited, along with the production of aerosols containing CFCs as propellants, except for medical and electronic uses. Halons have been banned from import since 1997. The Government is cataloguing enterprises that consume CFCs in the "National Register of Hazardous Substances" and is also working on the establishment of a National Halon Bank, an import/export control system and a project for the closing of the CFC manufacturing plant.
The primary motivation behind the considerable efforts to study stratospheric ozone depletion is the potential for biological consequences of increased solar UV-B (280-315 nm) radiation. Direct links between ozone depletion and biological impacts have been established for organisms living in Antarctic waters under the ozone ¨hole¨.Argentine scientists are studying the effects of changes in the UV climate on the ecosystems of southern South America. These areas have been subjected to increasingly high levels of ozone depletion during the last decade. One of the organisms that has been chosen for intensive research is Gunnera magellanica, a native perennial herb. Previous work in the Tierra del Fuego National Park has shown that leaf area expansion of this species is partially inhibited by ambient UV-B levels. A combination of UV monitoring and biological research showed that during the spring, despite frequent cloud cover, the passage of the ozone hole over Tierra del Fuego causes concomitant increases in UV radiation, leading to significant increases in DNA damage in the leaves of G. magellanica. The fluctuations in solar UV explained a large proportion of the variation in DNA damage (up to 68%).
As a result of the Montreal Protocol, the increasing trend of freon concentrations in the lower atmosphere has been slowing during recent years. Even a declining trend in some compounds has been measured. Freons and halons break up in the stratosphere, leading to the release of ozone-destroying chlorine and bromine. Despite the success of the Montreal Protocol, the stratospheric concentrations of chlorine and bromine are expected to stay at high levels in the coming decades. Extensive ozone depletion may therefore be detected during the next two decades or so. The ozone depletion phenomenon itself is expected to be detectable until the middle of the 21st century.
According to recent scientific results, climate change is also expected to affect stratospheric climate and ozone depletion efficiency. While the carbon dioxide concentration of the atmosphere is expected to increase, the lower atmosphere will become warmer and the upper atmosphere colder. These changes have already been measured. The cooling of the stratosphere stabilises the polar vortices and leads to enhanced ozone depletion. This, in turn, may result in greater ozone depletion in the coming decades; thereby leading to enhanced UVradiation in the springtime.
The text "Ozone depletion, a common problem to Finland and Argentina" was produced jointly by the Finnish Meteorological Institute, Finnish Ministry of the Environment, Finnish Environmental Institute, and Ministerio de Desarrollo Social y Medio Ambiente, Argentina.
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