1. Chapter 17
The Environment

2. Chapter Outline HOW CLEAN IS CLEAN ENOUGH? THE EXTERNALITIES APPROACH
THE PROPERTY RIGHTS APPROACH
ENVIRONMENTAL PROBLEMS AND THEIR ECONOMIC SOLUTIONS

3. How Clean is Clean Enough
Economists answer most “how much is enough” questions with the same answer: “until the marginal benefit equals the marginal cost.”
The right level of environmental cleanliness is achieved when the value of cleaning the environment a little more equals the cost of doing so.

4. The Dirty Room Example
Cleaning your room (dorm room or your own bedroom) can be done to many degrees
A short time can be spent getting things off the floor (high marginal benefit, low marginal cost).
More time can be spent with vacuuming and straightening (moderate marginal benefit, moderate marginal cost).
Even more time can be spent deep cleaning, removing stains from carpets, dusting all shelves and moving furniture so as to clean behind them (for most low marginal benefit and high marginal cost.)

5. Modeling Environmental Cleanup
Marginal Cost Marginal Benefit
Marginal Cost
Marginal Benefit
EQ*
Environmental Quality

6. The Externalities Approach
Externalities are the effects of a transaction that hurt or help people who are not a part of that transaction.
When a product affects someone other than the consumer of producer in a negative way, such as pollution, economists suggest that the market has failed.

7. When the Market Works for Everyone
Supply
Demand Q* P* P
Q/t A B C
Value to the Consumer:
0ACQ*
Consumers Pay Producers:
OP*CQ*
The Variable Cost to
Producers:
OBCQ*
Consumer Surplus:
P*AC
Producer Surplus:
BP*C

8. When Externalities are Present
If there are externalities then there is overproduction of a good.
The total cost of a good to society (called social cost) includes the costs of production incurred by the firm as well as the external costs.

9. When the Market Does Not Work for Everyone
Social Cost
External Cost
SMarginal Cost
D(Marginal Benefit) Q* P* P
Q/t Q’ P’

10. The Property Rights Approach
Coase’s Theorem
If there are no costs of bargaining between people and polluters then by assigning a property right (either the right of the firm to pollute or the right of people to be free from pollution) people and firms can negotiate to the correct level of production.

11. Why Coase’s Theorem Makes Sense
People do not pollute up their own private property nearly as much as they pollute Common Property.
Common Property is not owned by any individual but is owned by government or has some other collective ownership property.
This is because when they do they are removing value from themselves.

12. Problems with Coase’s Theorem
It is impossible for companies to negotiate with millions of citizens affected by their pollution.
The system picks a winner and a loser when it establishes the property right.

13. Natural Resources and Property Rights
Uses the concept of present value
Choose the rate of exploitation that maximizes profit.
The rate of exploitation that maximizes profit depends on whether the firm owns the property (or at least the long term right to exploit it.)

14. Various Environmental Problems and their Solutions
Problems of
Water pollution, Air Pollution, Extinction of Species, Acid Rain, Global Warming
Legal Solutions
Clean Water Act
Clean Air Act
Endangered Species Act

15. Legal vs. Economic Solutions
Legal solutions to environment problems typically limit or make illegal activities that harm the environment.
Economic solutions to environmental problems tend to discourage activities that harm the environment by making the people doing the harm recognize the cost of that harm.

16. Taxation as an Economic Solution
S+tax
tax P
SMarginal Cost Q’ P’ P*
D(Marginal Benefit) Q*
Q/t

17. Other Economic Solutions
Emission permits for SO2 in the Clean Air Act of 1990.
California’s old-car purchases

18. When There is No Authority to Tax or Regulate
Global Warming crosses governmental boundaries.
There is no motivation for an individual country to limit pollution that contributes to global warming.
No government can enforce the Kyoto Protocol