ECONOMICALLY OPTIMAL WILDFIRE INTERVENTION REGIMES

Wildfires in the United States result in total damages and costs that are likely to exceed billions of dollars annually. Land managers and policy makers propose higher rates of prescribed burning and other kinds of vegetation management to reduce amounts of wildfire and the risks of catastrophic losses. A wildfire public welfare maximization function, using a wildfire production function estimated using a time series model of a panel of Florida counties, is employed to simulate the publicly optimal level of prescribed burning in an example county in Florida (Volusia). Evaluation of the production function reveals that prescribed fire is not associated with reduced catastrophic wildfire risks in Volusia County Florida, indicating a short-run elasticity of -0.16 and a long-run elasticity of wildfire with respect to prescribed fire of -0.07. Stochastic dominance is used to evaluate the optimal amount of prescribed fire most likely to maximize a measure of public welfare. Results of that analysis reveal that the optimal amount of annual prescribed fire is about 3 percent (9,000 acres/year) of the total forest area, which is very close to the actual average amount of prescribed burning (12,700 acres/year) between 1994-99.Resource /Energy Economics and Policy,

Efficacy of mechanical fuel treatments for reducing wildfire hazard

Mechanical fuel treatments are increasingly being used for wildfire hazard reduction in the western U.S. However, the efficacy of these treatments for reducing wildfire hazard at a landscape scale is difficult to quantify, especially when including growth following treatment. A set of uneven- and even-aged treatments designed to reduce fire hazard were simulated on 0.8 million hectares of timberland in Colorado. Wildfire hazard ratings using torching and crowning indices were developed; stands were selected for treatment; treatment was simulated and hazard ratings were reassessed. The results show that the even-aged treatments initially place more area within our hazard thresholds than do the uneven-aged treatments and that the uneven-aged treatment that removes more small stems reduces risk more than the treatment removing more large stems. The treatment costs follow the same pattern, with the even-aged treatments costing least. However, potential revenues are, as expected, higher for the uneven-aged large treatment. The results also show that both higher costs and higher revenues accrue to the treatments applied to the higher risk stands. Treatments also have differing risk reductions depending on the initial risk category. Even without considering growth or revenues, the outcomes of a state-level treatment program are difficult to estimate. This implies that at a minimum, forest-level, if not state-level analyses including overall measures of risk reduction, costs, revenues and long-term effects need to be conducted in concert with setting priorities for treating timberlands.

CHAPTER 17 FORECASTING WILDFIRE SUPPRESSION EXPENDITURES FOR THE UNITED STATES

The wildland fire management organization of the United States Forest Service (USFS) operates under policy and budget legacies that began nearly-100 years ago and a forest fuel situation that is all too current. The confluence of these three factors contributes to increased burning and firefighting costs for the agency, an

Market impacts of a multiyear mechanical fuel treatment program in the U.S.

We describe a two-stage model of global log and chip markets that evaluates the spatial and temporal economic effects of government-subsidized fire-related mechanical fuel treatment programs in the U.S. West and South. The first stage is a goal program that allocates subsidies according to fire risk and location priorities, given a budget and a feasible, market-clearing market solution. The second stage is a quadratic welfare maximization spatial equilibrium model of individual State and global product markets, subject to the fuel treatment allocation. Results show that the program enhances timber market welfare in regions where treatments occur and globally but has an overall negative economic impact, once fuel treatment program costs are included. The overall cost of a mechanical fuel treatment program, when considering timber market welfare, transport costs, treatment costs, and timber receipts, exceeds $1000 per acre, implying that the long run fire effects and ecosystem net benefits of a treatment program would need to exceed this figure in order to justify widespread implementation.

The Lithosphere-Asthenosphere Boundary

Seismological models of upper-mantle structure are providing new constraints on the physical and chemical properties that differentiate the lithosphere from the asthenosphere. A wide variety of studies are consistent with an oceanic lithosphere that corresponds to a dry, chemically depleted layer over a hydrated, fertile asthenosphere. At the lithosphere-asthenosphere boundary beneath oceans and many Phanerozoic continental regions, observed seismic velocity gradients require a contrast in mantle hydration, fertility, and/or melt content, perhaps in combination with a vertical gradient in velocity anisotropy. Beneath cratons, evidence is growing for a deeper—but globally ubiquitous—asthenosphere. Some studies conclude that the cratonic lithosphere-asthenosphere boundary is gradual enough to be matched by a purely thermal gradient, whereas others indicate a more rapid transition and a contrast in composition or perhaps melt content