General Information:

• This exercise involves exploration of the seasonal and temporal changes in the size and shape of the Antarctic ozone hole and the development of an ozone hole over the Arctic.
• The questions are given on subsequent pages and in oncourse .
• Answers to all questions should be submitted via  oncourse .
• Check the exercise set II noticeboard ( news ) for announcements.

• The presence of ozone in the Earth's stratosphere provides a barrier for solar UV (ultraviolet) radiation, the harmful wavelengths of sunlight known to cause skin cancer.  Human usage of various volatile chemicals, notably chlorofluorocarbons (CFCs), poses a threat to the ozone layer because of they can catalytically destroy ozone molecules in the stratosphere.  Satellite measurements of atmospheric ozone levels enable monitoring of the extent of ozone depletion, especially over Antarctica where an ozone hole is created seasonally.
• Series of satellite measurements of ozone have been 
• Access to ozone data and animations of its temporal variability are found at: http://jwocky.gsfc.nasa.gov/multi/multi.html
• An alternate site providing images based on user-defined options is here: http://jwocky.gsfc.nasa.gov/eptoms/ep.html
• A well-presented introduction to the major principles & concepts related to ozone depletion can be found at: http://www.atm.ch.cam.ac.uk/tour/part1.html
• Part II of this four-part tour provides links to a movie showing the variations in the ozone hole over Antarctica from Nov 1978 to Jan 1992. 
• If any of the sites become inaccessible, I will provide information about alternatives or additions in the announcements here ( news ).
• If you encounter any difficulties with access to any of the sites please notify me by email ( simon@indiana.edu ) and I will attempt to resolve problems, or suggest other options as soon as possible.

---

Department of Geological Sciences, 
1001 E. Tenth Street, Bloomington, IN 47405-1403
Phone: (812) 855-5582  Last updated: 6 November 2002
Comments: simon@indiana.edu
Copyright 2000, The Trustees of Indiana University