Global Climate Change and Urban Sprawl

Carbon dioxide levels at the Mauna Loa Observatory

Ozone Depletion

  • The stratospheric ozone layer is important to the evolution of life on Earth and the continued health and survival of life on Earth.

  • Stratospheric ozone depletion is caused by anthropogenic factors, such as chlorofluorocarbons (CFCs), and natural factors, such as the melting of ice crystals in the atmosphere at the beginning of the Antarctic spring.

  • A decrease in stratospheric ozone increases the UV rays that reach the Earth’s surface. Exposure to UV rays can lead to skin cancer and cataracts in humans.

    1. Where can the largest concentration of ozone be found and what value does it have?

Greenhouse Gases and Effect

  • CO2 appears naturally in the atmosphere from sources such as respiration, decomposition, and volcanic eruptions.

  • There are a variety of natural sources of particulate matter.

  • The principal greenhouse gases are carbon dioxide, methane, water vapor, nitrous oxide, and chlorofluorocarbons (CFCs).

  • While water vapor is a greenhouse gas, it doesn’t contribute significantly to global climate change because it has a short residence time in the atmosphere.

  • The greenhouse effect results in the surface temperature necessary for life on Earth to exist.

  • Carbon dioxide, which has a global warming potential (GWP) of 1, is used as a reference point for the comparison of different greenhouse gases and their impacts on global climate change. Chlorofluorocarbons (CFCs) have the highest GWP, followed by nitrous oxide, then methane.

  • Global climate change, caused by excess greenhouse gases in the atmosphere, can lead to a variety of environmental problems including rising sea levels resulting from melting ice sheets and ocean water expansion, and disease vectors spreading from the tropics toward the poles. These problems can lead to changes in population dynamics and population movements in response.

Climate Change

  • Ocean warming is caused by the increase in greenhouse gases in the atmosphere.

  • Ocean warming can affect marine species in a variety of ways, including loss of habitat, and metabolic and reproductive changes.

  • Ocean warming is causing coral bleaching, which occurs when the loss of algae within corals cause the corals to bleach white. Some corals recover and some die.

  • Ocean acidification is the decrease in pH of the oceans, primarily due to increased CO2 concentrations in the atmosphere, and can be expressed as chemical equations.

  • As more CO2 is released into the atmosphere, the oceans, which absorb a large part of that CO2, become more acidic.

  • Anthropogenic activities that contribute to ocean acidification are those that lead to increased CO2 concentrations in the atmosphere: burning of fossil fuels, vehicle emissions, and deforestation.

  • Ocean acidification damages coral because acidification makes it difficult for them to form shells, due to the loss of calcium carbonate.

    1. What is the difference between weather and climate?

    2. Why is average global temperature the most important value when talking about climate change?

    3. What are the signs of climate change that are currently measurable?


  • Urbanization can lead to depletion of resources and saltwater intrusion in the hydrologic cycle.

  • Urbanization, through the burning of fossil fuels and landfills, affects the carbon cycle by increasing the amount of carbon dioxide in the atmosphere.

  • Impervious surfaces are human-made structures—such as roads, buildings, sidewalks, and parking lots—that do not allow water to reach the soil, leading to flooding.

  • Urban sprawl is the change in population distribution from high population density areas to low density suburbs that spread into rural lands, leading to potential environmental problems.

    1. What are some problems with urbanization?

    2. What are some ways we can sustainably manage our living areas (cities, suburbs, etc.)

    3. How do urban areas disrupt the ecology of an area?