Carolyn Kousky

Global climate policy: will cities lead the way?

Abstract While the Conference of the Parties wrangle at an international scale with climate policy, a quiet set of policies and measures is being implemented at a local scale by municipalities across the globe. This study examines the motivation municipalities have for undertaking policies to reduce their greenhouse gas emissions, when the theory of free-ridingwould predict that local administrations should find it difficult to unilaterally reduce their emissions for the benefit of the global climate. Through interviews with officials and/or staff in 23 municipalities in the United States enacting climate policy, data are gathered that suggest local government abatement policies are primarily a top—down decision based on what officials or staff members believe to be “good business” or rational policy choices. They are primarily driven by the potential for realised or perceived cost savings and co-benefits rather than by public pressure. Economic data from some dozen municipal projects are analyzed, finding, while municipalities lack sophisticated accounting techniques, some justification for the often-disputed claim that at least initial reductions in emissions can be made at cost savings. In the United States, with the lack of national abatement policies, it is municipalities that are leading the way in beginning to implement mitigation strategies, even if only for initial reductions.

Come Rain or Shine: Evidence on Flood Insurance Purchases in Florida

In the U.S., flood insurance is provided essentially through the National Flood Insurance Program (NFIP), a public-private program established in 1968. In the past 10 years, the program has radically expanded to cover

Learning from Extreme Events: Risk Perceptions after the Flood

1.1 trillion in assets today. This paper provides a detailed analysis of the largest flood insurance sample ever studied by focusing on the state of Florida, which accounts for 40 percent of the entire NFIP portfolio. We study the demand for flood insurance with a database of more than 7.5 million flood policies-in-force for the years 2000-2005, and all the claims filed in Florida during that period. We answer four questions: What are the characteristics of the buyers of flood insurance? What types of contracts (deductibles and coverage levels) are purchased? Where and when are claims paid and to what extent does mitigation work? How are prices determined and how much does NFIP insurance cost? Given the recent significant increase in the cost of catastrophes worldwide and the debate about the role that insurance can play to enhance adaptation to climate change, the responses to these questions shall be of interest to other countries too.

Private investment and government protection

This paper examines whether a severe flood causes homeowners to update their assessment of flood risk as seen in a change in the price of floodplain property. I use data on all single-family, residential property sales in St. Louis County, Missouri, between 1979 and 2006 in a repeat-sales model and a property fixed-effects model. After the 1993 flood on the Missouri and Mississippi rivers, property prices in 100-year floodplains did not change significantly, but prices in 500-year floodplains declined by between 2% and 5%. All property prices in municipalities located on the rivers fell postflood by 6% to 10%. (JEL Q51, Q54)

Understanding the Demand for Flood Insurance

Hurricane Katrina did massive damage because New Orleans and the Gulf Coast were not appropriately protected. Wherever natural disasters threaten, the government—in its traditional role as public goods provider—must decide what level of protection to provide to an area. It does so by purchasing protective capital, such as levees for a low-lying city. (“Protection” also consists of prohibiting projects that raise risk levels, such as draining swamps.)We show that if private capital is more likely to locate in better-protected areas, as would be expected, then the marginal social value of protection will increase with the level of protection provided. That is, the benefit function is convex, contrary to the normal assumption of concavity. When the government protects and the private sector invests, there may be multiple Nash equilibria due to the ill-behaved nature of the benefit function. Policy makers must compare them, rather than merely follow local optimality conditions, to find the equilibrium offering the highest social welfare.There is usually considerable uncertainty about the amount of private investment that will accompany any level of protection, further complicating the government’s choice problem. We show that when deciding on the level of protection to provide now, the government must take account of the option value of increasing the level of protection in the future. We briefly examine but dismiss the value of rules of thumb, such as building for 1000-year floods or other rules that ignore benefits and costs.

Responding to threats of climate change mega-catastrophes

In this paper, I examine the demand for flood insurance using data from every flood insurance policy-in-force in St. Louis County, Missouri, for the years 2000–2006. The contract choices of policyholders are examined, as are the determinants of take-up rates and coverage levels at the census tract level. Take-up rates are very low, with policy retention not as large a problem as writing policies initially. Risk drives demand but not always as predicted. Take-up rates increase with more land in 100-year floodplains and surprisingly, with more land in 500-year floodplains. Just less than one-third of all policies-in-force are outside 100-year floodplains. Take-up rates decline with levee protection and unexpectedly, along major rivers. Outside 100-year floodplains, where the mandatory purchase requirement does not apply, homeowners choose lower deductibles and more comprehensive coverage. The amount of coverage purchased increases with the value of a home, median income, and along major rivers.

The Unholy Trinity: Fat Tails, Tail Dependence, and Micro-Correlations

There is a low but uncertain probability that climate change could trigger “mega-catastrophes,” severe and at least partly irreversible adverse effects across broad regions. This paper first discusses the state of current knowledge and the defining characteristics of potential climate change mega-catastrophes. While some of these characteristics present difficulties for using standard rational choice methods to evaluate response options, there is still a need to balance the benefits and costs of different possible responses with appropriate attention to the uncertainties. To that end, we present a qualitative analysis of three options for mitigating the risk of climate mega-catastrophes—drastic abatement of greenhouse gas missions, development and implementation of geoengineering, and large-scale ex ante adaptation— against the criteria of efficacy, cost, robustness, and flexibility. We discuss the composition of a sound portfolio of initial investments in reducing the risk of climate change mega-catastrophes.

Informing Climate Adaptation: A Review of the Economic Costs of Natural Disasters, Their Determinants, and Risk Reduction Options

Recent events in the financial and insurance markets, as well as the looming challenges of a globally changing climate point to the need to re-think the ways in which we measure and manage catastrophic and dependent risks. Management can only be as good as our measurement tools. To that end, this paper outlines detection, measurement, and analysis strategies for fat-tailed risks, tail dependent risks, and risks characterized by micro-correlations. A simple model of insurance demand and supply is used to illustrate the difficulties in insuring risks characterized by these phenomena. Policy implications are discussed.

Floodplain Conservation as a Flood Mitigation Strategy: Examining Costs and Benefits

This paper reviews the empirical literature on the economic impacts of natural disasters to inform both climate adaptation policy and the estimation of potential climate damages. It covers papers that estimate the short- and long-run economic impacts of weather-related extreme events as well as studies regarding the determinants of the magnitude of those damages (including fatalities). The paper also includes a discussion of risk reduction options and the use of such measures as an adaptation strategy for predicted changes in extreme events with climate change.

Managing shoreline retreat: a US perspective

There is growing interest in floodplain conservation as a flood damage reduction strategy, particularly given the co-benefits protected lands provide. We evaluate one such investment—a greenway along the Meramec River in St. Louis County, Missouri. We estimate the opportunity costs, the avoided flood damages, and the capitalization of proximity to protected lands into nearby home prices. To estimate avoided flood damages, we undertake a parcel-level analysis using the Hazus-MH flood model, a GIS-based model developed for FEMA that couples a hydrology and hydraulics model with a damage model relating flood depths to property damage. We examine the distribution of damages across parcels, demonstrating that careful spatial targeting can increase the net benefits of floodplain conservation. In addition, we estimate a hedonic model and find that the increased property values for homes near protected lands are more than three times larger than the avoided flood damages, stressing the continued importance of more traditional conservation values. These benefits alone exceed the opportunity costs; the avoided flood damages further strengthen the economic case for floodplain conservation.