🛒Principles of Microeconomics Unit 12 – Environmental Protection & Externalities

Key Concepts

• Environmental economics studies the economic impact of environmental policies
• Externalities occur when the actions of an individual or firm affect the well-being of a third party
  • Negative externalities impose costs on others (pollution)
  • Positive externalities provide benefits to others (public parks)
• Market failure arises when the market fails to allocate resources efficiently
• Public goods are non-excludable and non-rivalrous (national defense)
• Common resources are non-excludable but rivalrous (fishing grounds)
• Property rights define the ownership and use of resources
• Pigouvian taxes internalize the cost of negative externalities
• Subsidies encourage activities that generate positive externalities

Environmental Challenges

• Climate change caused by greenhouse gas emissions (carbon dioxide)
• Air pollution from industrial activities and transportation
• Water pollution from agricultural runoff and industrial waste
• Deforestation due to logging, agriculture, and urbanization
• Biodiversity loss as a result of habitat destruction and overexploitation
• Soil degradation from intensive farming practices and erosion
• Ocean acidification caused by increased atmospheric carbon dioxide
• Waste management challenges, including plastic pollution

Market Failure and Externalities

• Market failures occur when the market outcome is not socially optimal
• Externalities create a divergence between private and social costs/benefits
• Negative production externalities arise when a firm's production affects others (factory emissions)
  • Marginal social cost (MSC) exceeds marginal private cost (MPC)
• Positive production externalities occur when production benefits others (research and development)
  • Marginal social benefit (MSB) exceeds marginal private benefit (MPB)
• Negative consumption externalities happen when consumption imposes costs on others (secondhand smoke)
• Positive consumption externalities arise when consumption benefits others (education)
• Coase theorem suggests that bargaining can resolve externalities if transaction costs are low

Policy Instruments

• Command-and-control regulations set specific standards or limits (emissions caps)
• Market-based instruments use price signals to incentivize behavior
  • Pigouvian taxes correct negative externalities by raising the price (carbon tax)
  • Subsidies encourage positive externalities by lowering the price (renewable energy subsidies)
• Tradable permits establish a market for pollution rights (cap-and-trade)
• Voluntary agreements rely on self-regulation and corporate social responsibility
• Information disclosure promotes transparency and consumer awareness (eco-labels)
• Liability rules hold polluters responsible for damages (Superfund)
• Government provision of public goods (national parks)

Cost-Benefit Analysis

• Cost-benefit analysis (CBA) evaluates the net benefits of a policy or project
• Benefits include direct and indirect positive impacts (improved health, ecosystem services)
• Costs include direct expenses and opportunity costs (construction costs, foregone development)
• Present value calculations discount future costs and benefits
  • Net present value (NPV) = $\sum_{t=0}^{T} \frac{B_t - C_t}{(1+r)^t}$
• Sensitivity analysis tests the robustness of CBA results to changes in assumptions
• Distributional impacts consider how costs and benefits are shared among different groups
• Challenges in CBA include quantifying non-market values and dealing with uncertainty

Case Studies

• Acid Rain Program in the United States used a cap-and-trade system for sulfur dioxide emissions
• Montreal Protocol successfully phased out ozone-depleting substances
• Payments for ecosystem services (PES) schemes compensate landowners for conservation (Costa Rica)
• Congestion pricing reduces traffic and air pollution in cities (London, Singapore)
• Deposit-refund systems encourage recycling of bottles and cans (Germany)
• Renewable portfolio standards mandate a minimum share of renewable energy (California)
• Fisheries management through individual transferable quotas (ITQs) to prevent overfishing (Iceland)

Controversies and Debates

• Discounting the future raises questions about intergenerational equity
• Valuing non-market goods, such as biodiversity and cultural heritage, is challenging
• Distributional impacts of environmental policies can be regressive (carbon taxes)
• The role of cost-benefit analysis in decision-making is debated
  • Critics argue that CBA ignores important ethical and moral considerations
• The precautionary principle suggests taking action in the face of uncertainty
• Debate over the use of market-based instruments versus command-and-control regulations
• Controversy surrounding the use of genetically modified organisms (GMOs) in agriculture
• The relationship between economic growth and environmental sustainability is complex

Future Directions

• Developing more comprehensive and integrated environmental-economic models
• Improving methods for valuing ecosystem services and natural capital
• Designing policy mixes that combine different instruments for effective environmental management
• Promoting international cooperation to address global environmental challenges (climate change)
• Encouraging eco-innovation and the transition to a circular economy
• Incorporating behavioral insights into environmental policy design (nudges)
• Exploring the potential of nature-based solutions and green infrastructure
• Addressing the links between environment, health, and social justice (environmental justice)