Page 535 - Environment: The Science Behind the Stories

• Despite some remaining uncertainties, the scientific com- fallen far short of what is needed to limit climate change.
munity feels that evidence for humans’ role in influencing (pp. 528–529)
climate is strong enough to justify taking action to reduce • Developing renewable energy technologies presents
emissions. (pp. 522–523)
economic opportunities. (pp. 529–530)
Suggest ways we may respond to climate change • Some U.S. states and cities are acting to address emissions.

• Both adaptation and mitigation are necessary. (p. 525) (p. 530)
• Conservation, energy efficiency, and new clean and • Emissions trading programs provide a way to harness the
renewable energy sources will help reduce greenhouse gas free market and engage industry in reducing emissions.
emissions. (pp. 525–526) (pp. 530–531)
• New automotive technologies and investment in public • A carbon tax, specifically a fee-and-dividend approach, is
transportation will help reduce emissions. (pp. 526–527) another option. (p. 531)
• Addressing climate change will require multiple strategies. • Individuals and corporations are increasingly exploring
(p. 527) carbon offsets and other means of reducing personal carbon
footprints. (pp. 531–533)
• The Kyoto Protocol provided a first step for nations to
begin addressing climate change. (p. 528) • Some scientists are so anxious about our lack of response
to climate change that they are now studying potential geo-
• International efforts to design a treaty to follow the engineering options. (p. 532)
Kyoto Protocol have made some progress, but have

Testing Your Comprehension

1. What happens to solar radiation after it reaches Earth? 6. Describe how rising sea levels, caused by global warm-
How do greenhouse gases warm the lower atmosphere? ing, can create problems for people. How is climate
2. Why is carbon dioxide considered the main greenhouse change affecting marine ecosystems?
gas? Why are carbon dioxide concentrations increasing 7. How might a warmer climate affect agriculture? How is it
in the atmosphere? affecting distributions of plants and animals? How might
3. How can scientists learn about climatic history? it affect human health?
4. Has simulating climate change with computer programs 8. Briefly explain why water vapor may either contribute to or
been effective in helping us predict climate? Briefly slow global warming.
describe how these programs work. 9. What roles have international treaties played in address-
5. List three major trends in climate that scientists have doc- ing climate change? Give two specific examples.
umented so far. Now list three future trends that they are 10. How is a cap-and-trade emissions program different from
predicting, along with their potential impacts. enacting a carbon tax? Describe the pros and cons of the
two approaches.

Seeking Solutions

1. Some people argue that we need “more proof” or “better 2. Describe several ways in which we can reduce greenhouse
science” before we commit to substantial changes in gas emissions from transportation. Which approach do
our energy economy. How much certainty do you think you think is most realistic, which approach do you think
we need before we should take action regarding climate is least realistic, and why?
change? How much certainty do you need in your own 3. Suppose that you would like to make your own lifestyle
life before you make a major decision? Should nations carbon-neutral and that you aim to begin by reduc-
and elected officials follow a different standard? Do you ing the emissions you are responsible for by 25%.
believe that the precautionary principle (pp. 283, 401) What three actions would you take first to achieve this
is an appropriate standard in the case of global climate reduction?
534 change? Why or why not?

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