Depletion of the Ozone Layer

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2 Chapter 12 Depletion of the Ozone Layer 1] Background 467 2] Status: Antarctic Ozone Hole and UV radiation in Chile 468 3] Pressure: Ozone Depleting Substances 472 4] National Response towards the Depletion of the Ozone Layer 474

3 Capa Ozone Capa de Layer de Ozono Ozono The stratospheric ozone forms the Ozone layer, which prevents potentially harmful UV-B ultraviolet radiation,, from reaching Earth. 18% Absorbed 31% Reflected 51% Reaches the surface DEPLETION OF THE OZONE LAYER STRATOSPHERE aerosol F F cl cl CFC cl cl c F cl aerosol solar energy cl cl cl cl cl Chlorine atoms o o cl o cl cl cl cl cl STRATOSPHERE o o o cl 1. Ozone Depleting Substances (ODS) used by humans, such as CFCs, are released into the air and rise into the stratosphere. 2. The UV rays break apart the CFCs in the stratosphere. Chlorine atoms are released. 3. Chlorine atoms break apart ozone molecules. One chlorine atom can continue to break apart ozone molecules throughout a century. Source: Own elaboration based on PNUMA (21) TROPOSPHERE

4 467 ozone capítulo 12 Introduction Abstract The ozone layer is a shield that protects us from ultraviolet radiation coming from the sun, which is harmful in high levels. Due to the anthropic use of several compounds called Ozone Depleting Substances (ODS), the formation of this protection shield is prevented. Chile is particularly vulnerable to this phenomenon, because it is located near the Antartic Ozone Hole. Chile has joined the global effort to revert this phenomenon and recover the ozone layer by ratifying the Vienna Convention and the Montreal Protocol in 199, with the aim to comply with the timeframe to reduce the consumption of ODS. Background The ozone layer 1 acts as a protection shield preventing ultraviolet radiation reaching Earth from the sun. The total ozone is usually lower in regions closer to the equator and greater near the poles, due to the seasonal behavior of winds in the stratosphere. The stratospheric ozone prevents the entrance of UVB ultraviolet radiation to the planet s surface, thus avoiding the negative effects that this produces for people and the environment. It also influences the thermal distribution of the atmosphere, serving as a regulator for Earth s climate. Without this filtering effect from the ozone layer, life on our planet would not be as we know it today. The disruption of the natural cycle of the stratospheric ozone has as a direct consequence on the increase of the ultraviolet radiation that reaches ground level. If the ultraviolet radiation is not absorbed in adequate quantities, it can cause negative impacts on a significant amount of life forms. For example, in humans, the exposure to increases of ultraviolet B radiation (UV-B: nm) increases the risk of skin cancer, cataracts, and weakens the immune system. In addition, the excessive exposure to UV-B can diminish the growth of plants, and affect unicellular organisms and aquatic systems. 1 1] The ozone is a gas formed by three oxygen atoms (O3). This gas is present in the Earth s atmosphere in different concentrations, with geographical and seasonal variations, as well as by different altitude. More than 9% of the ozone is found between 15 and 24 km of altitud in the stratosphere, which is the layer of the atmosphere located between 8 and 5 km from ground level. This stratospheric ozone strip is known as the ozone layer. Usually, the ozone column is lower near the equator and higher near the poles, due to the seasonal behavior of winds in the stratosphere. The ozone layer works in different ways, depending on the kind of UV radiation: UV-A: radiation passes through completely; UV-B: radiation is partially filtered, but if there is a hole in the ozone layer it let s more of it pass through; and UV-C, the most harmful one, is completely blocked by the ozone layer.

5 468 capítulo 12 ozone depletion 2 Status: Antarctic Ozone Hole and UV radiation in Chile 2] During the winter of Antarctica, the polar vortex isolates the air in the center. This air becomes so cold that stratospheric clouds are formed. These clouds house chemical reactions that are unique on the planet, releasing chlorine and bromine atoms that come from ODS. As soon as the sun rays (UV) appear in the spring, these break and release the chemicals, generating a significant depletion of the ozone layer in Antarctica. 3] The Dobson Unit (DU) is a measurement of the thickness of the ozone layer, equivalent to.1 mm at normal pressure and temperature conditions (1 atm and ºC respectively), and it is expressed in number of molecules. The AOH is defined, by convention, as the region where the total ozone column is equal or lower to 22 DU (Dobson Units). In addition to the diminishment of the global ozone, which affects the entire planet, there is another phenomenon that occurs every southern spring called the Antarctic Ozone Hole (AOH). The AOH is a significant diminishment of the Antarctica Stratospheric Ozone, which is related to the activity of the Antarctic Polar Vortex 2. Figure 1 shows an image generated with data collected through instruments on board the OMI (Ozone Monitoring Instrument) satellites, in which the total ozone column is color coded. Blue indicates an ozone column between 1 and 2 DU (Dobson Units 3 ), and corresponds to the thinnest area of the planetary ozone layer. Clearly, it is possible to see that one of the edges of the AOH is located over the Magallanes and Chilean Antarctica Region, leaving the country in a particularly vulnerable condition in comparison to the rest of the world. The area that defines the AOH does not remain constant in time nor in space. Its size changes as does its form, which sometimes causes the border to move towards the southern Patagonia, generating significant reductions in the protective ozone layer. The AOH has a seasonal activity, that is, it begins its activity by the end of August and continues throughout December, with annual changes. Total Ozone observed by the OMI, October 1, 21. Source: Tropospheric Emission Monitoring Internet Service (TEMIS). fig. 1 South America Antarctica Total Ozone (Dobson Units)

6 469 ozone capítulo 12 Figure 2 shows the evolution of the AOH, since 1979 until 21. The area that is covered by the AOH grew constantly from 1 million square kilometers in 1979 to close to 3 million km 2 in 26. On the other hand, the minimum of the total ozone column, measured in Antarctica, decreased from 19 DU to 73 DU in 1996 (Figure 3). In the last decade it is possible to see a level of stability, both in size as well as in the minimum measured. UV Rays UV Rays UV Rays UV Rays UV Rays UV Rays UV Rays AOH Antarctic Ozone Hole Area (million km 2 ) fig. 2 Size of the Antarctic Ozone Hole, Source: Data provided by Profesor Dr. Claudio Casiccia, Ozone Lab, University of Magallanes Ozone (DU) fig. 3 Minimum ozone column, measured in the Antarctic continent, Note: Ozone (DU) = Ozone column measured in Dobson Units. Source: Data provided by Profesor Dr. Claudio Casiccia, Ozone Lab, University of Magallanes

7 47 capítulo 12 ozone depletion According to historical data obtained from instruments by satellite and latitude means, Table 1 shows the ozone column means for some Chilean cities and different periods of time. The table contains the means of the series, which corresponds to a period without the influence of the AOH; the means for a greater period, between 1978 and 21; and also the 21 average, as current reference. At the same time, each period has been subdivided according to the seasons of the year, primarily due to the seasonal variation presented by the ozone layer, with minimum values during fall-winter and high values during spring-summer. Ozone column means (Dobson Units), according to the seasons of the Table 1 year and months, in different parts of Chile. Summer (Dec-Feb) Fall (Mar-May) Winter (Jun-Aug) Spring (Sep-Nov) Arica Iquique Copiapó Valparaíso-Santiago Concepción Valdivia- Puerto Montt Aysén Punta Arenas Base Frei- Antártica Source: Data provided by Profesor Dr. Claudio Casiccia, Ozone Lab, University of Magallanes. The data shows that there are no significant variations in the total ozone column in the selected cities except for the two southernmost locations, where the AOH influences the spring and summer values. All of the values presented in the table are in accordance with the global tendencies of the ozone layer state report, published by the panel of experts of the World Meteorological Organization (Scientific Assessment of Ozone Depletion, 21). Also, as previously mentioned, this information confirms that in general the total ozone is lower in regions closer to the equator and greater near the poles.

8 471 ozone capítulo 12 The World Health Organization (WHO), in collaboration with the United Nations Environment Programme (UNEP) and other organizations, has created a solar protection index, or the UV index. This index measures the intensity of UV radiation on the surface of the earth. The higher its value, the greater the amount of UV rays and, consequently, the health risk. Figure 4 shows, for the city of Punta Arenas, the evolution during 29 of the total ozone column and Figure 5, the ultraviolet radiation index (UVI) in the same southern city. For this year, it is clear that the AOH positioned itself there for several days, generating an increase in the UV radiation Ozone (DU) Ozone fig. 4 Ozone column (Dobson Units), in Punta Arenas, September through December, 29. Note: Ozone (DU) = Ozone column measured in Dobson units. Source: Data provided by Profesor Dr. Claudio Casiccia, Ozone Lab, University of Magallanes. UV Index fig. 5 Ultraviolet radiation (UV Index) observed in Punta Arenas, September through December, 29. Source: Data provided by Profesor Dr. Claudio Casiccia, Ozone Lab, University of Magallanes Radiation Year 29

9 472 capítulo 12 ozone depletion UV Ozone Layer Ozone Layer ODS 3 4] It is estimated that each chlorine atom can destroy about 1, ozone molecules before it vanishes in the stratosphere. Even though UV radiation continues constantly, creating ozone from oxygen, the presence of chlorine accelerates the destruction of the ozone, which reduces its global concentration. Pressure: Ozone Depleting Substances The ozone layer problem originated primarily by the release of hazardous subtances into the atmosphere due to industrial production and consumption. While this problem is the responsibility of all the countries in the world, it does not affect every country proportionally. The continous process of ozone layer formation has been affected by the presence of other elements of anthropic origin in the stratosphere, such as chlorine, fluor and bromine, deriving from Ozone Depleting Substances (ODS). These substances have interrupted the natural formation and destruction cycle of the ozone, which has led to the weakening of the ozone layer 4 According to the Montreal Protocol 5, the main ODS correspond to compounds such as chlorofluorocarbons (CFCs) and Hydrochlorofluorocarbons (HCFCs), used in refrigeration, foams, propellants, solvents and fire extinguishers; methyl bromide (BrMe), soil fumigants and pesticides; halons to extinguish fires; methyl chloroform, previously used as solvent; carbon tetrachloride (CCI4), which is used as a solvent in chemical laboratories. 5] The Montreal Protocol, related to ozone depleting substances, is an international agreement whose objective is to protect the ozone layer by reducing the generation and consumption of several substances that react with the ozone and are responsible for the depletion of the ozone layer. This agreement came into force on January, 1, 1989.

10 473 ozone capítulo 12 In the case of Chile, there is no ODS generation, and the exports are not significant, therefore, the national consumption calculation is made based on the imports of products that contain them. According to the Montreal Protocol, the substances entering through imports are regulated by the National Customs Service. During the period, there has been a significant decrease in the national consumption of ODS (see Figure 6), this is primarily explained by the significant decrease in the consumptio of CFCs. All of the ODS have decreased in time, except for HCFCs which have increased. fig. 6 National Total Consumption of Ozone Depleting Substances (ODP Tons), Source: Own elaboration based on data reported by the Ministry of the Environment to the Ozone Secretariat. ODP Tons 1,4 1,2 1, 8 HFCs Bromochloromethane Other CFCs completely halogenated Carbon Tetrachloride Methyl Chloroform Halons HCFCs Methyl Bromide CFCs Note: ODP = Ozone Depletion Potential. ODS consumption is calculated with the following formula: imports + production - exports. In Chile there is no production of ODS and the exports are minimal, therefore the consumption corresponds primarily to imports.

11 474 capítulo 12 ozone depletion 4 National Response towards the Depletion of the Ozone Layer 199 Montreal Protocol 6] The Montreal Protocol groups the main ODS into the following 5 appendices: Appendix A: CFCs and halons; Appendix B: other CFCs, methyl chloroform, carbon tetrachloride; Appendix C: HCFCs and bromochloromethane; and Appendix E: methyl bromide (BrMe). Appendix D is an indicative list of products containing ODS. Ozone layer depletion has been treated as a global problem. In this context, the Vienna Convention was subscribed as an agreement that protects human health and the environment from the adverse effects resulting from changes to the ozone layer. Thus, this agreement promotes research and the exchange of information in order to evaluate the impacts of human activities on the ozone layer and the effects of its alteration on human health and the environment. At the same time, the convention requests adopting legislative or administrative measures to control, limit, reduce or prevent human activities that have adverse effects on the ozone layer. Under the framework of the Vienna Convention, the Montreal Protocol was prepared with the aim of establishing a gradual timeframe to diminish the consumption of Ozone Depleting Substances (ODS). This protocol establishes deadlines for the reduction and elimination of such substances. The Panel of Experts of the Protocol estimates that, if all of the obligations the countries committed to are met, by the year 25 the ozone layer in the Northern Hemisphere will have recovered its levels from the 197s. In the case of the Southern Hemisphere, this will occur by the year 265. Chile ratified the Vienna Convention and the Montreal Protocol in 199. The Montreal Protocol 6 is a standard currently in force and the country has an obligation to meet the deadlines for the reduction and elimination of ODS. According to the requirements of the Montreal Protocol, since January 1 st, 21 the import of CFCs, halons and carbon tetrachloride were prohibited in Chile and, since 28, no imports of methyl chloroform have been reported. On the other hand, the prohibition to import methyl bromide will begin on January 1 st, 215. Figure 7 shows the evolution of the national consumption of each type of ODS during the period and the maximum consumption limits established by the Monreal Protocol from 26 to 215. As it can be seen, the goals for all the ODS have been accomplished. In the case of HCFCs, according to which that is stated, a deadline calendar was recently established for their reduction, therefore their absolute values will be calculated with the base line.

12 ODP Tons 1 9 CFCs ODP Tons 25 Halons ODP Tons 35 Methyl Bromide ODP Tons 25 Carbon Tetrachloride ODS Tons Methyl Chloroform ODP Tons HCFCs Use of ODPs fig. 7 National consumption of different ODPs (columns) and maximum limits of imports allowed, established by the Montreal Protocol (points), in ODP Tons. Note: In the case of carbon tetrachloride consumption during 27, there is a consumption value over the established limit; however, this is not considered a breach in compliance because in 28, Chile presented its Action Maximum limit allowed by the Montreal Protocol Plan to the Ozone Secretariat, where it showed that said import was for analytic and laboratory use, which was approved by the Implementation Committee. Source: Own elaboration based on data reported by the Ministry of the Environment to the Ozone Secretariat.

13 476 capítulo 12 ozone depletion Regarding HFCFs, the XIX Conference of Parties to the Montreal Protocol that took place in September, 27, approved an amendment to the deadlines for the reduction of these ODS. This amendment consisted of moving the baseline to the period and the total elimination date, beginning on January 1 st, 24 and allowing the use of only 2.5% between 23 and 239, exclusively for justified technical service and maintenance operations, this measure will be revised in 22. This adjustment starts with freezing the consumption starting on January 1 st, 213, at the baseline level. Then it sets a 1% decrease in the year 215, a 35% for 22, a 67.5% for 225 and 97.5% for 23, leaving a 2.5% until 24. Figure 8 shows the participation of different uses in the national consumption of HCFCs for 28, identified in the Management Plan for the elimination of HCFCs from Chile. Commercial Refrigeration/grocery stores 23% Industrial Refrigeration 19% Discontinuous Panels 13% Continuous Panels 11% National consumption (%) of HCFCs by type of use, 28. Source: Own elaboration. fig. 8 Polyol Exports Spray Air Conditioning System Cleansing 3% 7% 11% 11% Others 1% Residential Refrigeration 1% % 5% 1% 15% 2% 25% The HCFCs reduction marks the second and final phase of ODS reduction. To that end, all of the parties of the Montreal Protocol must elaborate a Management Plan for the elimination of HCFCs (or HPMP for HCFCs Phase-out Management Plan )

14 477 ozone capítulo 12 In this context, in December 21, Chile presented to the Multilateral Fund Secretariat, through the United Nations Development Programme (UNDP), the request to fund its HCFCs Phase-out Management Plan (HPMP), which contains 4 strategic approaches: a regulatory framework; support to the foam sector (discontinuous panels and spray); support to the refrigeration sector (refrigeration services and maintenance and air conditioning, including system cleansing); and dissemination, awareness and monitoring. The plan has a chronogram of activities, from 211 to 23, where the country will work with international implementation agencies such as the UNDP and the UNEP. The national plan sets two phases. The first, between 211 and 215, establishes activities to reduce the consumption of HCFCs in the refrigeration sector, with the support of regulatory aspects and public dissemination. Afterwards, between 215 and 23, reduction and phase-out activities will be implemented for the consumption of HCFCs in the refrigeration, air conditioning and foam sectors, with regulation support and public dissemination measures.

15 478 capítulo 12 ozone depletion National Program for the Protection of the Ozone Layer OZONE LAW The Ozone Program was created in Chile by the National Environment Commission (CONAMA) in 1993, with the aim to ensure the compliance of the Montreal Protocol in the country, acting as a focal point of said agreement. As part of this program, investment and technical assistance programs are prepared and executed, complemented with dissemination and awareness activities. To meet these goals, financial resources have been obtained from the Multilateral Fund of the Montreal Protocol, which have been disbursed by international implementation agencies (UNEP, UNDP, UNIDO, World Bank) or bilateral agencies (Environment Canada). Regarding regulatory aspects, on March 23 rd, 26, the Law N 2.96 came into force known as the Ozone Law, which establishes control mechanisms that are applicable to all ODS as well as dissemination, evaluation, prevention and protection measures against ultraviolet radiation. Complementary to this, Chile has developed other regulations, decrees and resolutions to contribute to the decrease in the consumption of ODS which are detailed in Table 2. Table 2 Name Year Description Law N 2.96, MINSEGPRES 26 Known as the Ozone Law, establishes control mechanisms for ODS. SD N 37/27, MINSEGPRES 27 Establishes maximum volumes of imports *. Res. N 3577, Agriculture and Livestock Service Res. Ex. N 563 y 5638, National Custom Service Res. N 159, Public Health Institute Standards applicable to ODS Establishes the obligation to declare the use of methyl bromide. Establishes the distribution mechanism for maximum volumes of imports **. 21 Establishes labelling for inhalers with CFCs. Notes: *Currently, it is being modified according to the new HFCFs deadlines. **Distribution mechanism for maximum volumes of imports: 8% among historical importers; 18% among new importers; 2% at the discretion of the Custom s Director (calculations adjustment). Source: Own elaboration.

16 479 ozone capítulo 12 Several projects have also been implemented to reduce and phase out the use of ODS under the National Program for the Protection of the Ozone Layer (see Table 3). As part of these actions, training has been implemented; good refrigeration practices have been added to the syllabus of technical and higher education; recovery and recycling programs, technological reconversions, as well as technical assistance have all be implemented to replace ODS in their activities. Table 3 Projects executed by International implementating Agency, since 24- to date. Agency Project Year World Bank Institutional Strengthening Technology Conversion Financing Programme (TECFIN I y II) (TECFIN I) (TECFIN II) Terminal Plan for Solvents Terminal Plan for Refrigeration UNDP Terminal Plan for Foams Halons Institutional Strengthening HPMP Preparation Environment Canada UNEP Management Plan for Refrigerants, Module 2: Training in good refrigeration practices (GRP), Syllabus Evaluation Management Plan for Refrigerants, Module 2: GRP standards, Demonstrative Reconditioning. Management Plan for Refrigerant, Module 3 (Recycling and Recovery Programs) Terminal Plan for CFCs Management Plan for Refrigerant, Module 1: Training and Customs Information System Management Plan for Refrigerant, Module 4: Awareness Campaign Management Plan for Refrigerant, Module 5: Monitoring UNIDO Terminal Project for Methyl Bromide (Investment component)

17 48 capítulo 12 ozone depletion 7] Dr. Claudio Casiccia, Director of the Ozone Laboratory of the University of Magallanes, is the representative of Chile for the Research Administrators Meeting on the Vienna Ozone Convention. Parallel to the actions of reducing the consumption of ODS, several ozone layer monitoring initiatives are being developed in the country. This is why, since 1991, the Ozone and UV Radiation Laboratory of the University of Magallanes has been researching the ozone levels in the stratosphere of Magallanes and the Chilean Antarctic. One of the most relevant projects is to Strengthen the UV radiation and ozone layer measurement capacities in Southern Patagonia, and their projection towards the community, where Ministry of the Environment (former CONAMA) works as the governmental counterpart 7.

18 481 ozone capítulo 12 References Abarca, J.F. y Casiccia, C. diciembre 22. Skin cancer and ultraviolet-b radiation under the Antarctic ozone hole: Southern Chile, Photodermatology, photoimmunology and photomedicine, 18(6): Casiccia, C., 21. Influence of the Antarctic Ozone Hole on the American Southern Cone Foz do Iguaçu, Brasil, 8-13 Aug. Casiccia, C., 28. Report of the ozone research in Chile. En: Proceeding of the VII Meeting of the Ozone Research Managers of the Parties to the Vienna Convention for the Protection of the Ozone Layer, may 28, Geneve, Switzerland: WMO Global Ozone Research and Monitoring Project Report N o 51. Casiccia, C., 21. The ozone layer is recovering in mid-latitudes. In: EGU General Assembly 21, 2-7 May 21, Vienna. Casiccia, C.; Kirchhoff, V.W.J.H. y Torres, A. C., 23. Simultaneous measurements of ozone and ultraviolet radiation: Spring 2, Punta Arenas, Chile. In: J. Atmos. Env. 37(3): Casiccia, C.; Zamorano, F. y Hernández, A. 28. Erythemal irradiance at the Magallanes Region and Antarctic Ozone Hole Atmósfera, Vol. 21(1), Kirchhoff, V.W.J.H.; Casiccia, C.; Zamorano, F., 2 de abril de The ozone hole over Punta Arenas, Chile. In: j. Geophys. res., vol 12, N o D7: Kirchhoff, V.W.J.H.; Zamorano, F.; Casiccia, C., UV-B Enhancements at Punta Arenas, Chile. J.Photochem. Photobiol. B, vol. 38: Munakata, N.; Schuck, N.; Casiccia, C., 26. Biological Monitoring of Solar UV Radiation at 17 Sites in Asia, Europe and South America from 1999 to 24. J.Photochem. Photobiol. B, doi: / RA-62, Vol 81, N o.6. Programa de las Naciones Unidas para el Medio Ambiente (PNUMA), 21. Guía educativa Ozono: educación básica. Ronald Van Der A, Bas Mijling. Knmi/Temis, 21. Ozone and UV forecast, Daily updated pictures and data, Ozone, Antarctic ozone hole at 1 Oct 21. Available at: php?date=2111.