Chapter 20
The Atmosphere: Climate, Climate Change, and Ozone Depletion
Chapter Outline:
I. Atmosphere and Weather
A. Atmospheric Structure
B. Weather
1. Flowing Air
2. Convection
3. Jet Streams
4. Put Together . . .
II. Climate
A. Climates in the Past
1. Further Back
2. Rapid Changes
B. Oceans and Atmosphere
1. Thermohaline Circulation
2. Abrupt Change
3. What If . . . ?
III. Global Climate Change
A. The Earth as a Greenhouse
1. Warming Processes
a. Greenhouse Gases
2. Cooling Processes
a. Volcanoes
b. Aerosols
c. Ozone Depletion
3. Solar Variability
a. Thus . . .
B. The Greenhouse Gases
1. Carbon Dioxide
a. Monitoring
b. Sources
c. Sinks
2. Other Greenhouse Gases
a. Water Vapor
b. Methane
c. Nitrous Oxide
d. Ozone
e. CFCs and Other Halocarbons
C. Evidence of Climate Change
1. Intergovernmental Panel on Climate Change
2. An Increasing Body of Observations Gives a Collective Picture of a Warming World and Other Changes in the Climate System
a. Correlation?
b. Satellites?
c. Other Changes
d. Sea Level
3. Emissions of GHGs and Aerosols Due to Human Activities Continue to Alter the Atmosphere in Ways that Are Expected to Affect the Climate
4. Confidence in the Ability of Models to Project Future Climate Has Increased
5. There is New and Stronger Evidence that Most of the Warming Observed Over the Last 50 Years Is Attributable to Human Activities
6. Human Influences Will Continue to Change Atmospheric Composition throughout the 21st Century
a. Assumptions
7. Global Average Temperature and Sea Level Are Projected to Rise under All IPCC Scenarios
a. Climate Change
b. Benefits?
c. Rising Sea Level
8. Anthropogenic Climate Change Will Persist for Many Centuries
9. Further Action Is Required to Address Remaining Gaps in Information and Understanding
10. Other Assessments
a. U.S. National Assessment
b. U.S. National Research Council
IV. Response to Climate Change
A. Response 1: Mitigation
1. What Has Been Done
a. Framework Convention on Climate Change
b. Kyoto Protocol
c. U.S. Policy
d. Global Climate Change Initiative
e. U.S. Climate Change Science Program
f. States and Corporations
B. Response 2: Adaptation
1. New Funds
2. New Report
3. Strategies
4. Conclusions
V. Depletion of the Ozone Layer
A. Radiation and Importance of the Shield
B. Formation and Breakdown of the Shield
1. Halogens in the Atmosphere
a. Rowland and Molina
b. EPA Action
2. The Ozone “Hole”
a. Polar Vortex
3. Arctic Hole?
4. Further Ozone Depletion
C. Coming to Grips with Ozone Depletion
1. Montreal Protocol
2. Action in the United States
3. Final Thoughts