Michael A. Gresko (okergm@aol.com, Stevenson HS)

 

Web Quest: The Ozone layer and Chlorofluorocarbons

 

Introduction: We have taken an initial look at the topic of stratospheric ozone depletion. Causes have been examined. Spray cans, air conditioners and refrigerators have been identified as sources of chlorofluorocarbons. The subsequent catalytic degradation of ozone was addressed. The damage done to the Antarctic food chain by excess solar ultraviolet radiation because of the thinning of the protective ozone layer was discussed. Plankton populations have been decreasing, which in turn led to decreases in krill and hence penguins. Also, worldwide frog populations have been decimated possibly because of ultraviolet damage to fragile eggs. Melanoma or skin cancer rates have risen dramatically in the Southern Hemisphere, lands closest to the growing hole in the Antarctic ozone layer.

            You are assigned today to play the role of a dermatology group. Your group will make a presentation to a Congressional Committee, which is having hearings on the Montreal Protocols. Under the present Administration, we will pretend that the United States is contemplating withdrawal from these accords.

 

Task: Your responsibility today is to do additional research on the web. You will use this information tonight to: 1) develop a definition of the ozone problem with regard to a potential departure from the Montreal Protocols using your perspective as dermatologists; 2) summarize the information that you gathered today; 3) identify the causes of ozone depletion; 4) evaluate what would happen if the United States departs from the Montreal Protocols; 5) develop alternative solutions to the ozone problem; 6) select the best solution; and 7) evaluate the solution chosen for costs and benefits. If you have forgotten any of these processes, refer to http://www.maxwell.syr/edu/plegal/tips for the PPA model. You will have the first twenty minutes tomorrow, to put together an oral presentation for the committee chairman, Mr. Gresko. You will be graded on 1) your homework and 2) your oral presentation. The first is an individual grade. The second will be a single grade based on the group’s oral report ( convince me ).

 

Process: The class will be divided into four groups, roughly equivalent to previous committees. Each has been assigned eight or nine web sites to examine. The groups will make their own specific assignments. Remember to take notes, you will not be permitted to print out the articles. I suggest that you set up seven sheets of paper, each headed by the seven steps as outlined in the Task section above, and keep your note organized. For homework, you will write out your notes in paragraph form, and this will be submitted for grading. Be sure to indicate which websites you examined. Tomorrow, your class president will act pro temp as leader to organize the class’ project, an oral presentation. Given the shortness of time, I suggest that seven presenters be chosen, each supported by atleast one ‘research assistant’, corresponding to the seven steps in the task. You will have access to everyone’s homework before it is collected. You must complete the organization of your oral presentation in twenty minutes. You will have fifteen minutes to complete the presentation itself, so one of you must be chosen to keep track of time (hint: 15 minutes for 7 presenters is about how many minutes each?).

 

Resources: You have already seen a Power Point presentation on this topic and read about it in Chemistry: An Environmental Perspective. You will now gather evidence for your group oral presentation, which is tomorrow. For this purpose you will be divided into the following teams with their websites:

                       

Team                                                   Websites

Ritha                http://www.gfdl.noaa.gov      http://www.doc.mmu.ac.uk/aric/eae/enter.html

Marjorie           http://www.foe.org/ozone/intro.html

Stephanie         http://www.sepp.org               http://www.globalchange.org

Sahara              http://www.globalchange.org  http://www.elp.gov.bc.ca/epd/epda/ar/ozone

                        http://www.ozone.org                        http://www.nas.nasa.gov/about/education/ozone/

 

Casey               http://sedac.ciesin.org/ozone http://cpc.ncep.noaa.gov/products/stratosphere

Stefan              http://www.unep.ch/ozone   http://atm.ch.cam.ac.uk/tour/index.html

Jennifer S.        http://www4.nas.edu/beyond/beyonddiscovery.nsf/web/ozon..

Simone                        http://www.ozone-sec.ch.cam.ac.uk/theseo_brochure_html/..

                        http://cybersleuth-kids.com   http://www.ch.ic.ac.uk/vchemlib/mol/mol.html

 

John                 http://es.epa.gov/oeca/eptdd/adi.html

Eric                 http://www.nedo.go.jp/GET/index2.html

Kevin              http://www.gcrio.org/unep1998

Gregory           http://environment.about.com/msuboz.htm

                        http://science.nas.nasa.gov/Services/Education/Resource…

                        http://www.columbia.edu/~rw187

                        http://www.elp.gov.bc.ca/epd/epda/ar/ozone/index.html

                        http://www.dar.cssiro.av/ozone/default.htm

           

Elias                http://www.epa.gov/ozone      http://www.ilsr.org/ecotax/greentax.html

Jennifer B.       http://www.sepp.org/ozone/ozone.html

Maria               http://www.acdi-cida.gc.ca/xpress/dex/dex9507.htm

Aria                 http://www.nerc-bas.ac.uk/public/icd

                        http://www.ec.gc.ca/ozone/indexe.htm

                        http://www.environmental-expert.com/welcome-airpollution

 

I remind you, do not assume that the websites next to your name are meant for you. The class is grouped in teams of four and each team is responsible for all websites to the right of their names. As part of a team, you will make up the individual assignment.

 

 

 

 

 

 

Evaluation:  The homework summaries of your individual web quest efforts will be graded on the basis of fifty points (30 for completing each of the seven PPA steps correctly, and 20 for demonstrating an adequate understanding of the science behind your problem). The group oral  presentation will be worth 50 points (7 points per PPA element, based on 4 points for the appropriate science and 3 points for  showing an understanding of what to include in each step, and  one point for convincing me that your position is correct).

 

Conclusion: The effects of human activities can have many unforeseen consequences. This is especially so if the activity is the result of an application of science (gas laws and organic chemistry in the case of the spray cans). If proper research is not done before hand, then the costs of cleaning up errors can be great in terms of dollar output, jobs lost, retraining, and physical disabilities.