(Related to the Apply the Concept on page 163) An economist for the Brookings Institution argued that "a price on carbon would minimize the cost of steering economic activity away from the greenhouse gas emissions that threaten the climate." a. In what sense does a carbon tax put a price on carbon? b. How would a carbon tax steer economic activity away from greenhouse gas emissions? c. Why might a carbon tax be less costly to the economy than a command-and- control approach to reducinggreenhouse gases? Why might a command-and-control approach to pollution control still be more politically popular than a carbon tax? Include in your answer a brief discussion of the difference between the normative analysis and positive analysis of this policy issue.

Environmental economics is a branch of economics that focuses on the economic effects of environmental policies and the costs and benefits of environmental actions. It examines how economic activities affect the environment and how they can be shaped to support sustainable development. For instance, implementing a carbon tax, as discussed in the exercise, addresses one core aspect of environmental economics: pricing environmental externalities. An externality is an economic term for a cost or benefit that affects a party who did not choose to incur that cost or benefit. With environmental externalities, the price of a product or service might not reflect its true cost to society, that is, the negative impacts on the environment.

A carbon tax integrates these external costs into the price, making it part of the economic equation. In doing so, it attempts to rectify market failures where the full environmental costs of greenhouse gas (GHG) emissions are not accounted for in the market prices of carbon-heavy products and services. This alignment of environmental impact with economic reality, a key objective of environmental economics, incentivizes individuals and businesses to alter their behavior in favor of reduced emissions, often leading to innovations in technology and processes.

Greenhouse gas emissions are pivotal to the study of environmental economics as they link directly to climate change. Gases like carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), which are emitted by certain industrial activities, agriculture, deforestation, and the burning of fossil fuels, trap heat in the Earth's atmosphere. This results in global warming and a host of related problems, such as extreme weather events and rising sea levels.

Economically, GHG emissions represent a critical area where policy can influence market behavior. By putting a price on carbon emissions, a carbon tax discourages the overuse of carbon-based fuels and stimulates investment in cleaner energy sources. This, in turn, is expected to decrease the amount of GHG emitted into the atmosphere, mitigating the impact on climate change. Therefore, understanding the mechanisms behind GHG emissions is fundamental for policymakers to develop incentives or regulations to curb them and for businesses and consumers to adapt to those policies effectively.

The command-and-control approach refers to government interventions that prescribe specific actions, technologies, or standards for reducing pollution or improving environmental quality. These rules are often rigid, specifying which technology to use or how to conduct certain processes. While they can be effective in achieving specific environmental outcomes, command-and-control regulations can be costly and offer little flexibility for the regulated entities. They do not allow businesses to choose the most cost-effective method to reduce emissions but require compliance with specific government-mandated practices or technologies, which may not always be the most current or efficient.

Market-based approaches, like carbon taxes, on the other hand, provide incentives for businesses to innovate and find their own best methods to reduce emissions—this flexibility can lead to more cost-effective and potentially greater environmental benefits compared to the command-and-control method. However, as mentioned in the exercise solution, market-based strategies might face political resistance as they imply a tax increase and can produce more gradual, less visible outcomes than direct regulations.

In environmental policy debates, economists often distinguish between normative and positive analysis—a foundational concept in economics. Positive analysis involves describing and predicting economic phenomena. It is strictly focused on facts and cause-and-effect relationships and is free from personal beliefs. For example, a positive analysis of a carbon tax would detail how it works, its economic implications, and its projected effects on GHG emissions.

In contrast, normative analysis involves value judgments and opinions about what the economy 'should' look like. It considers ethical perspectives, societal goals, and policy recommendations. When economists engage in normative analysis regarding a carbon tax, they deliberate over whether implementing such a tax is desirable or beneficial based on a range of economic and social criteria. These may include equity implications, effectiveness, and alignment with broader societal values. This kind of analysis is key to policy formulation but can be controversial, as different stakeholders hold varying values and opinions about what policy outcomes ought to be prioritized.