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Volcanic Ozone Hole

Volcanic Ozone Hole. Volcanic Ozone Hole. An "ozone hole" could form over the North Pole after future major volcanic eruptions – within next 30 years - Azadeh Tabazadeh, scientist at NASA's Ames Research Center, Moffett Field, Calif winter stratosphere temperatures highly variable in Arctic

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Volcanic Ozone Hole

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  1. Volcanic Ozone Hole www.assignmentpoint.com

  2. Volcanic Ozone Hole • An "ozone hole" could form over the North Pole after future major volcanic eruptions – within next 30 years - Azadeh Tabazadeh, scientist at NASA's Ames Research Center, Moffett Field, Calif • winter stratosphere temperatures highly variable in Arctic • If a period of high volcanic activity coincides with a series of cold Arctic winters www.assignmentpoint.com

  3. How would this happen? • Large volcanic eruptions - pump sulfur compounds into atmosphere. • Compounds form sulfuric acid clouds - similar polar stratospheric clouds - nitric acid and water. • Form in upper atmosphere - very cold conditions - destruction of ozone over poles. • Volcanic sulfuric acid clouds add to the ozone-destroying power of polar stratospheric clouds www.assignmentpoint.com

  4. Global implications • Could volcanic aerosols cause ozone destruction in warmer regions of the globe? • Could ozone destruction occur at lower altitude corresponding with level of volcanic aerosol? • YES – 1993 Artic winter not extremely cold but ozone loss was very high – why? – sulphurous Pintatubo clouds at lower altitude www.assignmentpoint.com

  5. Chemical modelling • 'blow' (or advect) chemical species around the globe using known or computed weather patterns - winds, temperatures and pressures • rates of chemical reactions dependent on temperature, pressure, and with photolytic processes, the position of the sun www.assignmentpoint.com

  6. Schematic of chemical model www.assignmentpoint.com

  7. Different types of models • Box model – single point – only chemistry simulated – cheap model • Trajectory model – trajectory – ‘box model that moves’ – wind fields  path • 3-D model – grid of box models with vertical levels- more realistic – meteorology - complex www.assignmentpoint.com

  8. Comparison of model output and satellite observation www.assignmentpoint.com

  9. Health Consequences • Skin cancers, sunburn, eye damage, cataracts • estimated 10 % reduction ozone layer  25 % increase non-melanoma skin cancer -temperate latitudes by 2050 • Suppress immune system • DNA mutation of existing disease bacteria and viruses www.assignmentpoint.com

  10. UV, ozone and melanoma Quite deadly Distinct latitudinal distribution www.assignmentpoint.com

  11. And . . . elevated risk of • herpes viruses • human immunodeficiency virus HIV- 1 • variety of papilloma viruses • leishmaniasis • malaria • forms of tuberculosis • leprosy • lupus erthematodes • dermatitis • E. coli • Staphylococcus aureus www.assignmentpoint.com

  12. Biological Consequences • Biologically damaging young, new shoots • Southern Ocean - most productive marine ecosystem - less phytoplankton (8.5per cent decr)- food for microscopic animals - eaten by krill – sustain seals, penguins, and baleen whales • 6 % ozone depletion  loss 7 million tons fish per year www.assignmentpoint.com

  13. And . . • damages DNA marine bacteria, starfish and urchins larvae • alters ocean chemistry www.assignmentpoint.com

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