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Journal articles on the topic 'Ozone layer depletion – Mpumalanga'

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Published: 4 June 2021

Last updated: 1 February 2022

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1

De Winter-Sorkina, Renata. "Impact of ozone layer depletion I: ozone depletion climatology." Atmospheric Environment 35, no. 9 (March 2001): 1609–14. http://dx.doi.org/10.1016/s1352-2310(00)00436-2.

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2

Rowland, F. Sherwood. "Stratospheric ozone depletion." Philosophical Transactions of the Royal Society B: Biological Sciences 361, no. 1469 (February 21, 2006): 769–90. http://dx.doi.org/10.1098/rstb.2005.1783.

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Solar ultraviolet radiation creates an ozone layer in the atmosphere which in turn completely absorbs the most energetic fraction of this radiation. This process both warms the air, creating the stratosphere between 15 and 50 km altitude, and protects the biological activities at the Earth's surface from this damaging radiation. In the last half-century, the chemical mechanisms operating within the ozone layer have been shown to include very efficient catalytic chain reactions involving the chemical species HO, HO 2 , NO, NO 2 , Cl and ClO. The NO X and ClO X chains involve the emission at Earth's surface of stable molecules in very low concentration (N 2 O, CCl 2 F 2 , CCl 3 F, etc.) which wander in the atmosphere for as long as a century before absorbing ultraviolet radiation and decomposing to create NO and Cl in the middle of the stratospheric ozone layer. The growing emissions of synthetic chlorofluorocarbon molecules cause a significant diminution in the ozone content of the stratosphere, with the result that more solar ultraviolet-B radiation (290–320 nm wavelength) reaches the surface. This ozone loss occurs in the temperate zone latitudes in all seasons, and especially drastically since the early 1980s in the south polar springtime—the ‘Antarctic ozone hole’. The chemical reactions causing this ozone depletion are primarily based on atomic Cl and ClO, the product of its reaction with ozone. The further manufacture of chlorofluorocarbons has been banned by the 1992 revisions of the 1987 Montreal Protocol of the United Nations. Atmospheric measurements have confirmed that the Protocol has been very successful in reducing further emissions of these molecules. Recovery of the stratosphere to the ozone conditions of the 1950s will occur slowly over the rest of the twenty-first century because of the long lifetime of the precursor molecules.

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3

De Winter-Sorkina, Renata. "Impact of ozone layer depletion II:." Atmospheric Environment 35, no. 9 (March 2001): 1615–25. http://dx.doi.org/10.1016/s1352-2310(00)00437-4.

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4

Rowlands, Ian H. "OZONE LAYER DEPLETION AND GLOBAL WARMING." Peace & Change 16, no. 3 (July 1991): 260–84. http://dx.doi.org/10.1111/j.1468-0130.1991.tb00572.x.

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5

Christidou, Vasilia, and Vasilis Koulaidis. "Children's models of the ozone layer and ozone depletion." Research in Science Education 26, no. 4 (December 1996): 421–36. http://dx.doi.org/10.1007/bf02357453.

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6

IBUSUKI, Takashi. "Depletion of Stratospheric Ozone Layer by Chlorofluorocarbons." Journal of Japan Oil Chemists' Society 41, no. 9 (1992): 867–71. http://dx.doi.org/10.5650/jos1956.41.867.

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7

Mickle, R. E., J. W. Bottenheim, W. R. Leaitch, and W. Evans. "Boundary layer ozone depletion during AGASP-II." Atmospheric Environment (1967) 23, no. 11 (January 1989): 2443–49. http://dx.doi.org/10.1016/0004-6981(89)90255-2.

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8

Lu, Jinpeng, Fei Xie, Hongying Tian, and Jiali Luo. "Impacts of Ozone Changes in the Tropopause Layer on Stratospheric Water Vapor." Atmosphere 12, no. 3 (February 24, 2021): 291. http://dx.doi.org/10.3390/atmos12030291.

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Stratospheric water vapor (SWV) changes play an important role in regulating global climate change, and its variations are controlled by tropopause temperature. This study estimates the impacts of tropopause layer ozone changes on tropopause temperature by radiative process and further influences on lower stratospheric water vapor (LSWV) using the Whole Atmosphere Community Climate Model (WACCM4). It is found that a 10% depletion in global (mid-low and polar latitudes) tropopause layer ozone causes a significant cooling of the tropical cold-point tropopause with a maximum cooling of 0.3 K, and a corresponding reduction in LSWV with a maximum value of 0.06 ppmv. The depletion of tropopause layer ozone at mid-low latitudes results in cooling of the tropical cold-point tropopause by radiative processes and a corresponding LSWV reduction. However, the effect of polar tropopause layer ozone depletion on tropical cold-point tropopause temperature and LSWV is opposite to and weaker than the effect of tropopause layer ozone depletion at mid-low latitudes. Finally, the joint effect of tropopause layer ozone depletion (at mid-low and polar latitudes) causes a negative cold-point tropopause temperature and a decreased tropical LSWV. Conversely, the impact of a 10% increase in global tropopause layer ozone on LSWV is exactly the opposite of the impact of ozone depletion. After 2000, tropopause layer ozone decreased at mid-low latitudes and increased at high latitudes. These tropopause layer ozone changes at different latitudes cause joint cooling in the tropical cold-point tropopause and a reduction in LSWV. Clarifying the impacts of tropopause layer ozone changes on LSWV clearly is important for understanding and predicting SWV changes in the context of future global ozone recovery.

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9

Strong, C., J. D. Fuentes, R. E. Davis, and J. W. Bottenheim. "Thermodynamic attributes of Arctic boundary layer ozone depletion." Atmospheric Environment 36, no. 15-16 (May 2002): 2641–52. http://dx.doi.org/10.1016/s1352-2310(02)00114-0.

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10

Anderson, Alun. "Depletion of ozone layer drives competitors to cooperate." Nature 331, no. 6153 (January 21, 1988): 201. http://dx.doi.org/10.1038/331201a0.

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11

Pekel, Feyzi Osman, and Esra Özay. "Turkish High School Students' Perceptions of Ozone Layer Depletion." Applied Environmental Education & Communication 4, no. 2 (April 2005): 115–23. http://dx.doi.org/10.1080/15330150590934598.

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12

Dameris, Martin. "Depletion of the Ozone Layer in the 21st Century." Angewandte Chemie International Edition 49, no. 3 (December 8, 2009): 489–91. http://dx.doi.org/10.1002/anie.200906334.

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13

Zhao, Xiaoyi, Dan Weaver, Kristof Bognar, Gloria Manney, Luis Millán, Xin Yang, Edwin Eloranta, Matthias Schneider, and Kimberly Strong. "Cyclone-induced surface ozone and HDO depletion in the Arctic." Atmospheric Chemistry and Physics 17, no. 24 (December 19, 2017): 14955–74. http://dx.doi.org/10.5194/acp-17-14955-2017.

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Abstract. Ground-based, satellite, and reanalysis datasets were used to identify two similar cyclone-induced surface ozone depletion events at Eureka, Canada (80.1° N, 86.4° W), in March 2007 and April 2011. These two events were coincident with observations of hydrogen deuterium oxide (HDO) depletion, indicating that condensation and sublimation occurred during the transport of the ozone-depleted air masses. Ice clouds (vapour and crystals) and aerosols were detected by lidar and radar when the ozone- and HDO-depleted air masses arrived over Eureka. For the 2007 event, an ice cloud layer was coincident with an aloft ozone depletion layer at 870 m altitude on 2–3 March, indicating this ice cloud layer contained bromine-enriched blowing-snow particles. Over the following 3 days, a shallow surface ozone depletion event (ODE) was observed at Eureka after the precipitation of bromine-enriched particles onto the local snowpack. A chemistry–climate model (UKCA) and a chemical transport model (pTOMCAT) were used to simulate the surface ozone depletion events. Incorporating the latest surface snow salinity data obtained for the Weddell Sea into the models resulted in improved agreement between the modelled and measured BrO concentrations above Eureka. MERRA-2 global reanalysis data and the FLEXPART particle dispersion model were used to study the link between the ozone and HDO depletion. In general, the modelled ozone and BrO showed good agreement with the ground-based observations; however, the modelled BrO and ozone in the near-surface layer are quite sensitive to the snow salinity. HDO depletion observed during these two blowing-snow ODEs was found to be weaker than pure Rayleigh fractionation. This work provides evidence of a blowing-snow sublimation process, which is a key step in producing bromine-enriched sea-salt aerosol.

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14

Evans, W. F. J. "A hole in the Arctic polar ozone layer during March 1986." Canadian Journal of Physics 67, no. 2-3 (February 1, 1989): 161–65. http://dx.doi.org/10.1139/p89-027.

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A craterlike structure or "hole" in the Arctic polar ozone layer during March 1986 has been observed in the total ozone images from the total ozone mapping spectrometer instrument on the NIMBUS 7 satellite. Observations from ozonesondes in the vicinity of this crater show a depleted region in the altitude profile from 10 to 16 km. This altitude region of depleted ozone is similar to the depleted layer observed from 12 to 18 km within the Antarctic ozone hole. A comparison has been made between the ozone altitude profile outside the crater at Resolute, N.W.T., Canada (75°N), and the ozone altitude profile inside the crater at Lindenberg, German Democratic Republic, (55°N). The difference in these profiles demonstrates that the crater is due to a process that has altered the altitude distribution of ozone in the 10–16 km region. This depletion could be attributed to either a vertical circulation or a chemical-depletion process.

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15

Drake, Frances. "Stratospheric ozone depletion - an overview of the scientific debate." Progress in Physical Geography: Earth and Environment 19, no. 1 (March 1995): 1–17. http://dx.doi.org/10.1177/030913339501900101.

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For almost half a century it was widely believed that the photochemistry of the stratosphere and hence ozone distribution were well understoood. As observations revealed a gap between observed and predicted values it was recognized that a number of substances acted as catalysts thereby increasing the destruction of ozone and that humanity could augment those catalysts and affect the ozone layer. Initial concern focused on nitrogen oxides from the exhausts of supersonic transport, but attention switched in the mid-1970s to chlorofluorocarbons (CFCs). Although the theory of anthropogenic ozone depletion by CFCs found widespread scientific support the perceived threat was minimized in particular by successive model predictions downgrading the amount of depletion. The appearance of the ozone hole over Antarctica in the mid-1980s reopened the debate as to whether such depletion was anthropogenic or natural in origin. It also highlighted the model's inadequate treatment of the processes occurring in the stratosphere and the importance of dynamics and radiative transfer in stratospheric ozone destruction. Scientific consensus again favours the anthropogenic depletion of the ozone layer. In conclusion it is considered that the degree of consensus outweighs the image of scientific uncertainty that is often portrayed in relation to the issue of stratospheric ozone depletion.

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16

Cao, L., H. Sihler, U. Platt, and E. Gutheil. "Numerical analysis of the chemical kinetic mechanisms of ozone depletion and halogen release in the polar troposphere." Atmospheric Chemistry and Physics 14, no. 7 (April 15, 2014): 3771–87. http://dx.doi.org/10.5194/acp-14-3771-2014.

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Abstract. The role of halogen species (e.g., Br, Cl) in the troposphere of polar regions has been investigated since the discovery of their importance for boundary layer ozone destruction in the polar spring about 25 years ago. Halogen species take part in an auto-catalytic chemical reaction cycle, which releases Br2 and BrCl from the sea salt aerosols, fresh sea ice or snowpack, leading to ozone depletion. In this study, three different chemical reaction schemes are investigated: a bromine-only reaction scheme, which then is subsequently extended to include nitrogen-containing compounds and chlorine species and corresponding chemical reactions. The importance of specific reactions and their rate constants is identified by a sensitivity analysis. The heterogeneous reaction rates are parameterized by considering the aerodynamic resistance, a reactive surface ratio, β, i.e., the ratio of reactive surface area to total ground surface area, and the boundary layer height, Lmix. It is found that for β = 1, a substantial ozone decrease occurs after five days and ozone depletion lasts for 40 h for Lmix = 200 m. For about β ≥ 20, the time required for major ozone depletion ([O3] < 4 ppb) to occur becomes independent of the height of the boundary layer, and for β = 100 it approaches two days, 28 h of which are attributable to the induction and 20 h to the depletion time. In polar regions, a small amount of NOx may exist, which stems from nitrate contained in the snow, and may have a strong impact on the ozone depletion. Therefore, the role of nitrogen-containing species on the ozone depletion rate is studied. The results show that the NOx concentrations are influenced by different chemical reactions over different time periods. During ozone depletion, the reaction cycle involving the BrONO2 hydrolysis is dominant. A critical value of 0.0004 of the uptake coefficient of the BrONO2 hydrolysis reaction at the aerosol and saline surfaces is identified, beyond which the existence of NOx species accelerates the ozone depletion event, whereas for lower values, deceleration occurs.

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17

Simpson, W. R., R. von Glasow, K. Riedel, P. Anderson, P. Ariya, J. Bottenheim, J. Burrows, et al. "Halogens and their role in polar boundary-layer ozone depletion." Atmospheric Chemistry and Physics 7, no. 16 (August 22, 2007): 4375–418. http://dx.doi.org/10.5194/acp-7-4375-2007.

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Abstract. During springtime in the polar regions, unique photochemistry converts inert halide salt ions (e.g. Br−) into reactive halogen species (e.g. Br atoms and BrO) that deplete ozone in the boundary layer to near zero levels. Since their discovery in the late 1980s, research on ozone depletion events (ODEs) has made great advances; however many key processes remain poorly understood. In this article we review the history, chemistry, dependence on environmental conditions, and impacts of ODEs. This research has shown the central role of bromine photochemistry, but how salts are transported from the ocean and are oxidized to become reactive halogen species in the air is still not fully understood. Halogens other than bromine (chlorine and iodine) are also activated through incompletely understood mechanisms that are probably coupled to bromine chemistry. The main consequence of halogen activation is chemical destruction of ozone, which removes the primary precursor of atmospheric oxidation, and generation of reactive halogen atoms/oxides that become the primary oxidizing species. The different reactivity of halogens as compared to OH and ozone has broad impacts on atmospheric chemistry, including near complete removal and deposition of mercury, alteration of oxidation fates for organic gases, and export of bromine into the free troposphere. Recent changes in the climate of the Arctic and state of the Arctic sea ice cover are likely to have strong effects on halogen activation and ODEs; however, more research is needed to make meaningful predictions of these changes.

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18

Aggarwal, Anjali, Reeta Kumari, Neeti Mehla, Deepali, Rishi Pal Singh, Sonal Bhatnagar, Kameshwar Sharma, Kuldeep Sharma, Vashishtha Amit, and Brijesh Rathi. "Depletion of the Ozone Layer and Its Consequences: A Review." American Journal of Plant Sciences 04, no. 10 (2013): 1990–97. http://dx.doi.org/10.4236/ajps.2013.410247.

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19

Roy, BilashChandra, Litan Debnath, Avisek Chaudhuri, and Sudhan Debnath. "A REVIEW ON OZONE LAYER DEPLETION, EFFECTS & IT’S SOLUTION." International Journal of Advanced Research 6, no. 4 (April 30, 2018): 385–92. http://dx.doi.org/10.21474/ijar01/6871.

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20

Simpson, W. R., R. von Glasow, K. Riedel, P. Anderson, P. Ariya, J. Bottenheim, J. Burrows, et al. "Halogens and their role in polar boundary-layer ozone depletion." Atmospheric Chemistry and Physics Discussions 7, no. 2 (March 29, 2007): 4285–403. http://dx.doi.org/10.5194/acpd-7-4285-2007.

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Abstract. During springtime in the polar regions, unique photochemistry converts inert halide salts ions (e.g. Br−) into reactive halogen species (e.g. Br atoms and BrO) that deplete ozone in the boundary layer to near zero levels. Since their discovery in the late 1980s, research on ozone depletion events (ODEs) has made great advances; however many key processes remain poorly understood. In this article we review the history, chemistry, dependence on environmental conditions, and impacts of ODEs. This research has shown the central role of bromine photochemistry, but how salts are transported from the ocean and are oxidized to become reactive halogen species in the air is still not fully understood. Halogens other than bromine (chlorine and iodine) are also activated through incompletely understood mechanisms that are probably coupled to bromine chemistry. The main consequence of halogen activation is chemical destruction of ozone, which removes the primary precursor of atmospheric oxidation, and generation of reactive halogen atoms/oxides that become the primary oxidizing species. The different reactivity of halogens as compared to OH and ozone has broad impacts on atmospheric chemistry, including near complete removal and deposition of mercury, alteration of oxidation fates for organic gases, and export of bromine into the free troposphere. Recent changes in the climate of the Arctic and state of the Arctic sea ice cover are likely to have strong effects on halogen activation and ODEs; however, more research is needed to make meaningful predictions of these changes.

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21

Kazarian, Ralph. "Alarming Depletion of Ozone Layer Above Antarctica: Scientists Seeking Cause." Environmental Conservation 13, no. 2 (1986): 178. http://dx.doi.org/10.1017/s0376892900036912.

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22

McConnell, J. C., G. S. Henderson, L. Barrie, J. Bottenheim, H. Niki, C. H. Langford, and E. M. J. Templeton. "Photochemical bromine production implicated in Arctic boundary-layer ozone depletion." Nature 355, no. 6356 (January 1992): 150–52. http://dx.doi.org/10.1038/355150a0.

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23

Pandav, Prashant P., S. B. Lokhande, and Shivprakash B. Barve. "Ecofriendly Refrigerants." Applied Mechanics and Materials 612 (August 2014): 181–85. http://dx.doi.org/10.4028/www.scientific.net/amm.612.181.

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The depletion of ozone layer and green house effects are worldwide problem. Refrigerants are part and source of depletion of ozone layer. As we using these Ecofriendly refrigerants then harm to ozone reduces. These are best option for recently running refrigerants. Eco-friendly refrigerant like hydroflurocarbons and hydrocarbons are replacing chlorofluorocarbons application.CFC is the most important member of CFC refrigerants. This paper, gives alternate to refrigerants that are causes ill effect on environment. Their performance with respect to recently used refrigerant compared. By this comparison benefits of Ecofriendly refrigerants discussed.

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24

Cao, L., H. Sihler, U. Platt, and E. Gutheil. "Numerical analysis of the chemical kinetic mechanisms of ozone depletion and halogen release in the polar troposphere." Atmospheric Chemistry and Physics Discussions 13, no. 9 (September 13, 2013): 24171–222. http://dx.doi.org/10.5194/acpd-13-24171-2013.

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Abstract. In recent years, the role of halogen species (e.g. Br, Cl) in the troposphere of polar regions is investigated after the discovery of their importance for boundary layer ozone destruction in the polar spring. Halogen species take part in an auto-catalytic chemical cycle including key self reactions. In this study, several chemical reaction schemes are investigated, and the importance of specific reactions and their rate constants is identified by a sensitivity analysis. A category of heterogeneous reactions related to HOBr activate halogen ions from sea salt aerosols, fresh sea ice or snow pack, driving the "bromine explosion". In the Arctic, a small amount of NOx may exist, which comes from nitrate contained in the snow, and this NOx may have a strong impact on ozone depletion. The heterogeneous reaction rates are parameterized by considering the aerodynamic resistance, a reactive surface ratio, β, i.e. ratio of reactive surface area to total ground surface area, and the boundary layer height, Lmix. It is found that for β = 1, the ozone depletion process starts after five days and lasts for 40 h for Lmix = 200 m. Ozone depletion duration becomes independent of the height of the boundary layer for about β≥20, and it approaches a value of two days for β=100. The role of nitrogen and chlorine containing species on the ozone depletion rate is studied. The calculation of the time integrated bromine and chlorine atom concentrations suggests a value in the order of 103 for the [Br] / [Cl] ratio, which reveals that atomic chlorine radicals have minor direct influence on the ozone depletion. The NOx concentrations are influenced by different chemical cycles over different time periods. During ozone depletion, the reaction cycle involving the BrONO2 hydrolysis is dominant. A critical value of 0.002 of the uptake coefficient of the BrONO2 hydrolysis reaction at the aerosol and saline surfaces is identified, beyond which the existence of NOx species accelerate the ozone depletion event – for lower values, deceleration occurs.

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25

Jones, A. E., P. S. Anderson, M. Begoin, N. Brough, M. A. Hutterli, G. J. Marshall, A. Richter, H. K. Roscoe, and E. W. Wolff. "BrO, blizzards, and drivers of polar tropospheric ozone depletion events." Atmospheric Chemistry and Physics 9, no. 14 (July 17, 2009): 4639–52. http://dx.doi.org/10.5194/acp-9-4639-2009.

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Abstract. The source of bromine that drives polar boundary layer ozone depletion events (ODEs) is still open to some debate. While ODEs are generally noted to form under conditions of a shallow stable boundary layer, observations of depleted air under high wind conditions are taken as being transport-related. Here we report observations from Antarctica in which an unusually large cloud of BrO formed over the Weddell Sea. The enhanced BrO was observed over Halley station in coastal Antarctica, providing an opportunity to probe the conditions within an active "bromine explosion" event. On this occasion, enhanced BrO and depleted boundary layer ozone coincided with high wind speeds and saline blowing snow. We derive a simple model to consider the environmental conditions that favour ODEs and find two maxima, one at low wind/stable boundary layer and one at high wind speeds with blowing snow. Modelling calculations aiming to reproduce the wider regional or global impacts of ODEs, either via radiative effects or as a halogen source, will also need to account for high wind speed mechanisms.

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26

Jones, A. E., P. S. Anderson, M. Begoin, N. Brough, M. A. Hutterli, G. J. Marshall, A. Richter, H. K. Roscoe, and E. W. Wolff. "BrO, blizzards, and drivers of polar tropospheric ozone depletion events." Atmospheric Chemistry and Physics Discussions 9, no. 2 (April 3, 2009): 8903–41. http://dx.doi.org/10.5194/acpd-9-8903-2009.

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Abstract. The source of bromine that drives polar boundary layer ozone depletion events (ODEs) is still open to some debate. While ODEs are generally noted to form under conditions of a shallow stable boundary layer, observations of depleted air under high wind conditions are taken as being transport-related. Here we report observations from Antarctica in which an unusually large cloud of BrO formed over the Weddell Sea. The enhanced BrO was observed over Halley station in coastal Antarctica, providing an opportunity to probe the conditions within an active "bromine explosion" event. On this occasion, enhanced BrO and depleted boundary layer ozone coincided with high wind speeds and saline blowing snow. We derive a simple model to consider the environmental conditions that favour ODEs and find two maxima, one at low wind/stable boundary layer and one at high wind speeds with blowing snow. Modelling calculations aiming to reproduce the wider regional or global impacts of ODEs, either via radiative effects or as a halogen source, will also need to account for high wind speed mechanisms.

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27

Crang, Richard F. E., Audrey E. Vassilyev, and Yevgeney A. Miroslavov. "Soybean chloroplast responses to enhanced ultraviolet irradiation." Proceedings, annual meeting, Electron Microscopy Society of America 51 (August 1, 1993): 348–49. http://dx.doi.org/10.1017/s0424820100147582.

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Environmental concerns over the degradation of the earth’s stratospheric ozone layer have been expressed for the past decade in recognition that with ozone depletion, enhanced ultraviolet irradiation will be received at the earth's surface. Such increase in ultraviolet irradiation can be hypothetically determined by making appropriate computer calculations based on proposed cloud cover, season, latitude, elevation, and percent of stratospheric ozone depletion. We have proposed a 40% reduction in the ozone layer corresponding to a daily increase of 19.1 kJ in the limits of ultraviolet-B (UV-B) spectral irradiation (280-320 nm). This is within the range of realistic possibilities based on current estimated ozone depletion rates for the next 40-50 years. We wish to determine the extent to which chloroplasts are ultrastructurally altered compared with those from plants raised under ambient conditions lacking an UV-B irradiation component.Uninoculated seeds of soybean (Glycine max), cv. “Forrest” were sown in standardized greenhouse soil in 4" clay pots, watered daily, and fertilized once per week.

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28

Siegmund, Peter, Henk Eskes, and Peter van Velthoven. "Antarctic Ozone Transport and Depletion in Austral Spring 2002." Journal of the Atmospheric Sciences 62, no. 3 (March 1, 2005): 838–47. http://dx.doi.org/10.1175/jas-3320.1.

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Abstract The ozone budget in the Antarctic region during the stratospheric warming in 2002 is studied, using ozone analyses from the Royal Netherlands Meteorological Institute (KNMI) ozone-transport and assimilation model called TM3DAM. The results show a strong poleward ozone mass flux during this event south of 45°S between about 20 and 40 hPa, which is about 5 times as large as the ozone flux in 2001 and 2000, and is dominated by eddy transport. Above 10 hPa, there exists a partially compensating equatorward ozone flux, which is dominated by the mean meridional circulation. During this event, not only the ozone column but also the ozone depletion rate in the Antarctic region, computed as a residual from the total ozone tendency and the ozone mass flux into this region, is large. The September–October integrated ozone depletion in 2002 is similar to that in 2000 and larger than that in 2001. Simulations for September 2002 with and without ozone assimilation and parameterized ozone chemistry indicate that the parameterized ozone chemistry alone is able to produce the evolution of the ozone layer in the Antarctic region in agreement with observations. A comparison of the ozone loss directly computed from the model’s chemistry parameterization with the residual ozone loss in a simulation with parameterized chemistry but without ozone assimilation shows that the numerical error in the residual ozone loss is small.

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29

Anwar, Fakhra, Fahad Nazir Chaudhry, Saiqa Nazeer, Noshila Zaman, and Saba Azam. "Causes of Ozone Layer Depletion and Its Effects on Human: Review." Atmospheric and Climate Sciences 06, no. 01 (2016): 129–34. http://dx.doi.org/10.4236/acs.2016.61011.

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30

Bentham, G. "Depletion of the ozone layer: consequences for non-infectious human diseases." Parasitology 106, S1 (January 1993): S39—S46. http://dx.doi.org/10.1017/s0031182000086108.

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SUMMARYStratospheric ozone depletion threatens to increase exposure to ultraviolet (UV) radiation which is known to be a factor in a number of diseases. There is little doubt that cumulative exposure to UV radiation is important in the aetiology of non-melanoma skin cancers. Evidence is also strong for a link with cutaneous malignant melanoma, although here it appears to be intermittent intense exposure that is most damaging. More controversial is the view that exposure to solar radiation is a significant factor in ocular damage, particularly in the formation of cataracts. Earlier studies pointing to such an effect have been criticized and alternative aetiological hypotheses have been proposed. However, other studies do show an effect of UV exposure on cortical cataract. Concern is also growing that UV may be capable of activating viruses and have immunological effects that might exacerbate infectious disease. Very worrying is the possibility that UV exposure can activate the human immunodeficiency virus which might accelerate the onset of AIDS. Any such health effects that have been observed in human populations are the result of exposure to existing, naturally occurring levels of UV radiation. There is, therefore, great concern about the possible exacerbation of these impacts as a result of increased exposure to UV radiation associated with stratospheric ozone depletion. However, any assessment of the nature and scale of such impacts on human health has to deal with several major problems and these are the focus of this paper. There are uncertainties about recent trends in stratospheric ozone and problems in the prediction of future changes. Following on from this are the difficulties of estimating what effects these changes will have on UV flux at ground level in populated areas. Further problems arise in the prediction of changes in biologically significant doses to humans which might be affected by changes in behaviour as well as by changes in the environment. Finally, the limitations of existing epidemiological knowledge of the effects of UV exposure are a constraint on our ability to predict what the health effects of any changed UV doses might be.

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31

Henriksen, Thormod, Arne Dahlback, Søren H. H. Larsen, and Johan Moan. "ULTRAVIOLET-RADIATION and SKIN CANCER. EFFECT OF AN OZONE LAYER DEPLETION." Photochemistry and Photobiology 51, no. 5 (May 1990): 579–82. http://dx.doi.org/10.1111/j.1751-1097.1990.tb01968.x.

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32

DAHLBACK, ARNE, THORMOD HENRIKSEN, SøREN H. H. LARSEN, and KNUT STAMNES. "BIOLOGICAL UV-DOSES AND THE EFFECT OF AN OZONE LAYER DEPLETION." Photochemistry and Photobiology 49, no. 5 (May 1989): 621–25. http://dx.doi.org/10.1111/j.1751-1097.1989.tb08433.x.

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Charman, W. "Ocular hazards arising from depletion of the natural atmospheric ozone layer." Ophthalmic and Physiological Optics 10, no. 1 (January 1990): 111. http://dx.doi.org/10.1016/0275-5408(90)90184-z.

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34

Asira, Enim Enim. "Characterization of Chemical Processes Involved in Ozone Depletion." International Letters of Chemistry, Physics and Astronomy 21 (November 2013): 53–57. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.21.53.

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The earth’s carrying capacity to support human life has been overstretched by increasing need to meet food requirements, consumption of resources; amount of waste generation and choice of technologies. These activities release into the atmosphere, chemical constituents of varied concentrations. When these chemicals enter into the atmosphere, they are subjected to various transformations that yield products or intermediates that tend to alter atmospheric chemical balance. In recent years, the global problem of ozone depletion has underscored the danger of overstepping earth’s ability to absorb waste products. This study therefore, focuses on the various chemical reactions involved in ozone depletion and the effects of ozone layer depletion on plant, animals, materials and climate.

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35

Lehrer, E., G. Hönninger, and U. Platt. "A one dimensional model study of the mechanism of halogen liberation and vertical transport in the polar troposphere." Atmospheric Chemistry and Physics 4, no. 11/12 (December 6, 2004): 2427–40. http://dx.doi.org/10.5194/acp-4-2427-2004.

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Abstract. Sudden depletions of tropospheric ozone during spring were reported from the Arctic and also from Antarctic coastal sites. Field studies showed that those depletion events are caused by reactive halogen species, especially bromine compounds. However the source and seasonal variation of reactive halogen species is still not completely understood. There are several indications that the halogen mobilisation from the sea ice surface of the polar oceans may be the most important source for the necessary halogens. Here we present a one dimensional model study aimed at determining the primary source of reactive halogens. The model includes gas phase and heterogeneous bromine and chlorine chemistry as well as vertical transport between the surface and the top of the boundary layer. The autocatalytic Br release by photochemical processes (bromine explosion) and subsequent rapid bromine catalysed ozone depletion is well reproduced in the model and the major source of reactive bromine appears to be the sea ice surface. The sea salt aerosol alone is not sufficient to yield the high levels of reactive bromine in the gas phase necessary for fast ozone depletion. However, the aerosol efficiently "recycles" less reactive bromine species (e.g. HBr) and feeds them back into the ozone destruction cycle. Isolation of the boundary layer air from the free troposphere by a strong temperature inversion was found to be critical for boundary layer ozone depletion to happen. The combination of strong surface inversions and presence of sunlight occurs only during polar spring.

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36

Lehrer, E., G. Hönninger, and U. Platt. "The mechanism of halogen liberation in the polar troposphere." Atmospheric Chemistry and Physics Discussions 4, no. 3 (June 28, 2004): 3607–52. http://dx.doi.org/10.5194/acpd-4-3607-2004.

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Abstract. Sudden depletions of tropospheric ozone during spring were reported from the Arctic and also from Antarctic coastal sites. Field studies showed that those depletion events are caused by reactive halogen species, especially bromine compounds. However the source and seasonal variation of reactive halogen species is still not completely understood. There are several indications that the halogen mobilisation from the sea ice surface of the polar oceans may be the most important source for the necessary halogens. Here we present a 1-D model study aimed at determining the primary source of reactive halogens. The model includes gas phase and heterogeneous bromine and chlorine chemistry as well as vertical transport between the surface and the top of the boundary layer. The autocatalytic Br release by photochemical processes (bromine explosion) and subsequent rapid bromine catalysed ozone depletion is well reproduced in the model and the major source of reactive bromine appears to be the sea ice surface. The sea salt aerosol alone is not sufficient to yield the high levels of reactive bromine in the gas phase necessary for fast ozone depletion. However, the aerosol efficiently 'recycles' less reactive bromine species (e.g. HBr) and feeds them back into the ozone destruction cycle. Isolation of the boundary layer air from the free troposphere by a strong temperature inversion was found to be critical for boundary layer ozone depletion to happen. The combination of strong surface inversions and presence of sunlight occurs only during polar spring.

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37

Boulet, Louis-Philippe. "The Ozone Layer and Metered Dose Inhalers." Canadian Respiratory Journal 5, no. 3 (1998): 176–79. http://dx.doi.org/10.1155/1998/137198.

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The stratospheric ozone layer plays a crucial role in protecting living organisms against ultraviolet radiation. Chlorofluorocarbons (CFC) contained in metered-dose inhalers (MDIs) contribute to ozone depletion and in accordance with theMontreal Protocol on Substances That Deplete the Ozone Layerestablished 10 years ago, phase-out strageies have been developed worldwide for this category of agents. Alternatives to CFC-containing inhalers have been developed, such as powder inhalers and those using hydrofluoroalkanes (HFAs) as propellants, which have been shown to be as safe and effective as CFC-containing inhalers and even offer interesting advantages over older inhalers. The transition to non-CFC MDIs requires a major effort to make the new products available and to ensure adequate comparision with the previous ones. It also requires a harmonization of actions taken by industry, government, licencing bodies and patients or health professional associations to ensure adequate information and education to the public and respiratory care providers.

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38

Chen, Xuemeng, Lauriane L. J. Quéléver, Pak L. Fung, Jutta Kesti, Matti P. Rissanen, Jaana Bäck, Petri Keronen, et al. "Observations of ozone depletion events in a Finnish boreal forest." Atmospheric Chemistry and Physics 18, no. 1 (January 3, 2018): 49–63. http://dx.doi.org/10.5194/acp-18-49-2018.

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Abstract. We investigated the concentrations and vertical profiles of ozone over a 20-year period (1996–2016) at the SMEAR II station in southern Finland. Our results showed that the typical daily median ozone concentrations were in the range of 20–50 ppb with clear diurnal and annual patterns. In general, the profile of ozone concentrations illustrated an increase as a function of heights. The main aim of our study was to address the frequency and strength of ozone depletion events at this boreal forest site. We observed more than a thousand of 10 min periods at 4.2 m, with ozone concentrations below 10 ppb, and a few tens of cases with ozone concentrations below 2 ppb. Among these observations, a number of ozone depletion events that lasted for more than 3 h were identified, and they occurred mainly in autumn and winter months. The low ozone concentrations were likely related to the formation of a low mixing layer under the conditions of low temperatures, low wind speeds, high relative humidities and limited intensity of solar radiation.

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Seabrook, J. A., J. A. Whiteway, L. H. Gray, R. Staebler, and A. Herber. "Airborne lidar measurements of surface ozone depletion over Arctic sea ice." Atmospheric Chemistry and Physics 13, no. 12 (June 22, 2013): 6023–29. http://dx.doi.org/10.5194/acp-13-6023-2013.

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Abstract. A differential absorption lidar (DIAL) for measurement of atmospheric ozone concentration was operated aboard the Polar 5 research aircraft in order to study the depletion of ozone over Arctic sea ice. The lidar measurements during a flight over the sea ice north of Barrow, Alaska, on 3 April 2011 found a surface boundary layer depletion of ozone over a range of 300 km. The photochemical destruction of surface level ozone was strongest at the most northern point of the flight, and steadily decreased towards land. All the observed ozone-depleted air throughout the flight occurred within 300 m of the sea ice surface. A back-trajectory analysis of the air measured throughout the flight indicated that the ozone-depleted air originated from over the ice. Air at the surface that was not depleted in ozone had originated from over land. An investigation into the altitude history of the ozone-depleted air suggests a strong inverse correlation between measured ozone concentration and the amount of time the air directly interacted with the sea ice.

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Gray, Nigel J. "Potential health effects of greenhouse effect and ozone layer depletion in Australia." Medical Journal of Australia 155, no. 3 (August 1991): 207. http://dx.doi.org/10.5694/j.1326-5377.1991.tb142209.x.

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41

Ewan, Christine, Edward A. Bryant, G. Dennis Calvert, John Marthick, and Deanne Condon‐Paoloni. "Potential health effects of greenhouse effect and ozone layer depletion in Australia." Medical Journal of Australia 154, no. 8 (April 1991): 554–59. http://dx.doi.org/10.5694/j.1326-5377.1991.tb119455.x.

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42

Bahar, Mehmet, Hüseyin Bağ, and Orçun Bozkurt. "Pre-Service Science Teachers Understandings of an Environmental Issue: Ozone Layer Depletion." Ekoloji 18, no. 69 (December 27, 2008): 51–58. http://dx.doi.org/10.5053/ekoloji.2008.697.

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43

Solberg, Sverre, Norbert Schmidbauer, Arne Semb, Frode Stordal, and �ystein Hov. "Boundary-layer ozone depletion as seen in the Norwegian Arctic in spring." Journal of Atmospheric Chemistry 23, no. 3 (March 1996): 301–32. http://dx.doi.org/10.1007/bf00055158.

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44

Wu, Yutian, Lorenzo M. Polvani, and Richard Seager. "The Importance of the Montreal Protocol in Protecting Earth’s Hydroclimate." Journal of Climate 26, no. 12 (June 15, 2013): 4049–68. http://dx.doi.org/10.1175/jcli-d-12-00675.1.

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Abstract The 1987 Montreal Protocol regulating emissions of chlorofluorocarbons (CFCs) and other ozone-depleting substances (ODSs) was motivated primarily by the harm to human health and ecosystems arising from increased exposure to ultraviolet-B (UV-B) radiation associated with depletion of the ozone layer. It is now known that the Montreal Protocol has helped reduce radiative forcing of the climate system since CFCs are greenhouse gases (GHGs), and that ozone depletion (which is now on the verge of reversing) has been the dominant driver of atmospheric circulation changes in the Southern Hemisphere in the last half century. This paper demonstrates that the Montreal Protocol also significantly protects Earth’s hydroclimate. Using the Community Atmospheric Model, version 3 (CAM3), coupled to a simple mixed layer ocean, it is shown that in the “world avoided” (i.e., with CFC emissions not regulated), the subtropical dry zones would be substantially drier, and the middle- and high-latitude regions considerably wetter in the coming decade (2020–29) than in a world without ozone depletion. Surprisingly, these changes are very similar, in both pattern and magnitude, to those caused by projected increases in GHG concentrations over the same period. It is further shown that, by dynamical and thermodynamical mechanisms, both the stratospheric ozone depletion and increased CFCs contribute to these changes. The results herein imply that, as a consequence of the Montreal Protocol, changes in the hydrological cycle in the coming decade will be only half as strong as what they otherwise would be.

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45

LOUW, C. W. "DEPLETION OF STRATOSPHERIC OZONE RESULTING FROM GLOBAL GASEOUS POLLUTION." Clean Air Journal 7, no. 1 (June 3, 1986): 3–13. http://dx.doi.org/10.17159/caj/1986/7/1.7343.

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The possible depletion of the stratospheric ozone layer has become an issue of international importance. The primary concern is based on the possible inhibition of its functioning as a life protecting ultraviolet shield and the adverse biological and climatological effects that might result from this. There is, however, still considerable scientific uncertainty concerning this issue. It is against this background that an appraisal is given of the current state of knowledge regarding the potential for depletion of stratospheric ozone by global gaseous pollution and the attendant environmental effects. Special reference is made to the SA research effort that will make an important contribution towards understanding the tropospheric/stratospheric processes which play a role in the formation and destruction of ozone.

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46

Yalcin, Fatma Aggul, and Mehmet Yalcin. "Turkish Primary Science Teacher Candidates’ Understandings of Global Warming and Ozone Layer Depletion." Journal of Education and Training Studies 5, no. 10 (September 24, 2017): 218. http://dx.doi.org/10.11114/jets.v5i10.2225.

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The purpose of the study was to explore Turkish primary science teacher candidates' understanding of global warming and ozone layer depletion. In the study, as the research approach the survey method was used. The sample consisted of one hundred eighty nine third grade science teacher candidates. Data was collected using the tool developed by the researcher. The survey solicited written opinion responses to seven open-ended questions. Teacher candidates’ written opinions about global warming and ozone layer depletion were analyzed descriptively. The results of the analysis were presented as percentages and frequency. The findings suggest that prospective teachers’ understandings about these issues were limited and they had some significant common, misconceptions. Finally, the findings were discussed in comparison with the previous research with respect to environmental education.

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47

Langematz, Ulrike, Franziska Schmidt, Markus Kunze, Gregory E. Bodeker, and Peter Braesicke. "Antarctic ozone depletion between 1960 and 1980 in observations and chemistry–climate model simulations." Atmospheric Chemistry and Physics 16, no. 24 (December 20, 2016): 15619–27. http://dx.doi.org/10.5194/acp-16-15619-2016.

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Abstract. The year 1980 has often been used as a benchmark for the return of Antarctic ozone to conditions assumed to be unaffected by emissions of ozone-depleting substances (ODSs), implying that anthropogenic ozone depletion in Antarctica started around 1980. Here, the extent of anthropogenically driven Antarctic ozone depletion prior to 1980 is examined using output from transient chemistry–climate model (CCM) simulations from 1960 to 2000 with prescribed changes of ozone-depleting substance concentrations in conjunction with observations. A regression model is used to attribute CCM modelled and observed changes in Antarctic total column ozone to halogen-driven chemistry prior to 1980. Wintertime Antarctic ozone is strongly affected by dynamical processes that vary in amplitude from year to year and from model to model. However, when the dynamical and chemical impacts on ozone are separated, all models consistently show a long-term, halogen-induced negative trend in Antarctic ozone from 1960 to 1980. The anthropogenically driven ozone loss from 1960 to 1980 ranges between 26.4 ± 3.4 and 49.8 ± 6.2 % of the total anthropogenic ozone depletion from 1960 to 2000. An even stronger ozone decline of 56.4 ± 6.8 % was estimated from ozone observations. This analysis of the observations and simulations from 17 CCMs clarifies that while the return of Antarctic ozone to 1980 values remains a valid milestone, achieving that milestone is not indicative of full recovery of the Antarctic ozone layer from the effects of ODSs.

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Takahashi, Akihisa, Toshihiro Kumatani, Saori Usui, Ryoko Tsujimura, Takaharu Seki, Kouichi Morimoto, and Takeo Ohnishi. "Photoreactivation in Paramecium tetraurelia under Conditions of Various Degrees of Ozone Layer Depletion¶." Photochemistry and Photobiology 81, no. 4 (2005): 1010. http://dx.doi.org/10.1562/2005-03-16-ra-463r.1.

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Morales-Méndez, Jonathan-David, and Ramón Silva-Rodríguez. "Environmental assessment of ozone layer depletion due to the manufacture of plastic bags." Heliyon 4, no. 12 (December 2018): e01020. http://dx.doi.org/10.1016/j.heliyon.2018.e01020.

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Dove, Jane. "Student Teacher Understanding of the Greenhouse Effect, Ozone Layer Depletion and Acid Rain." Environmental Education Research 2, no. 1 (February 1996): 89–100. http://dx.doi.org/10.1080/1350462960020108.

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