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Topics Explored: Photochemical Smog, Thermal Inversion, Tropospheric Ozone, Pollution Management

This case study explores the causes and formation of photochemical smog through a very interesting and tragic historical smog event in 1952 London. Answer key included.

Case Study: Photochemical Smog (Teacher & Student Edition)

  • ZIP file containing 2 PDF files 
    (1 Teacher Edition and 1 Student Edition)

  • Next Generation Science Standards (NGSS):
    HS-ESS2-6. Develop a quantitative model to describe the cycling of carbon among the hydrosphere, atmosphere, geosphere, and biosphere. 
    HS-ESS2-7. Construct an argument based on evidence about the simultaneous coevolution of Earth’s systems and life on Earth.
    HS-ESS2-4. Use a model to describe how variations in the flow of energy into and out of Earth’s systems result in changes in climate. 
    HS-ESS3-4. Evaluate or refine a technological solution that reduces impacts of human activities on natural systems.
    HS-ESS3-6. Use a computational representation to illustrate the relationships among Earth systems and how those relationships are being modified due to human activity.


    AP® Environmental Science Learning Objectives:
    7.1 The combustion of fossil fuels releases nitrogen oxides into the atmosphere. They lead to the production of ozone, formation of photochemical smog, and convert to nitric acid in the atmosphere, causing acid rain. Other pollutants produced by fossil fuel combustion include carbon monoxide, hydrocarbons, and particulate matter.
    7.2 Explain the causes and effects of photochemical smog and methods to reduce it.
    7.3 Describe thermal inversion and its relationship with pollution.


    AP® Environmental Science Practices:
    Practice 1: Explain environmental concepts, processes, and models presented in written format. 
    Practice 2: Analyze visual representations of environmental concepts and processes. 
    Practice 3: Analyze sources of information about environmental issues.  
    Practice 4: Analyze research studies that test environmental principles.  
    Practice 5: Analyze and interpret quantitative data represented in tables, charts, and graphs.
    Practice 6: Apply quantitative methods to address environmental concepts.
    Practice 7: Propose and justify solutions to environmental problems.


    IB® Environmental Systems Learning Objectives:   
    5.7.1 State the source and outline the effect of tropospheric ozone.
    5.7.2 Outline the formation of photochemical smog.
    5.7.3 Describe and evaluate pollution management strategies for urban air pollution.

    AP® is a registered trademark registered by the College Board®. IB® is a trademark registered by the International Baccalaureate Organization®. This work/product/service has been developed independently from and is not endorsed by the College Board® or the International Baccalaureate Organization®. 

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