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• 1. [Article] Three essays on the economics of climate change, land use and carbon sequestration

  This dissertation's three essays explore the effects of climate change on land use changes in the U.S., how future land areas in all major land uses change by projecting land use at the regional scale ...

  Citation × Citation Citation Abstract Copy Title: Three essays on the economics of climate change, land use and carbon sequestration Author: Haim, David This dissertation's three essays explore the effects of climate change on land use changes in the U.S., how future land areas in all major land uses change by projecting land use at the regional scale under two IPCC climate change scenarios. Investigate how and what role should carbon sequestration plays as a mitigation strategy given uncertainty of climate impacts and, estimate how responsive the demand for and the supply of urban land is to changes in its price and how different climatic variables effect both the supply and the demand for urban land. The first essay uses an econometric model to project regional and national landuse changes in the U.S. under two IPCC climate change scenarios. The key driver of land-use change in the model is county-level measures of net returns to five major land uses. The net returns are modified for the IPCC scenarios according to assumed trends in population and income and projections from integrated assessment models of agricultural prices and agricultural and forestry yields. For both scenarios, we project large increases in urban land by the middle of the century, while the largest declines are in cropland area. Significant differences among regions in the projected patterns of land-use change are evident, including an expansion of forests in the Mountain and Plains regions with declines elsewhere. Comparisons to projections with no climate change effects on prices and yields reveal relatively small differences. Thus, our findings suggest that future land use patterns in the U.S. will be shaped largely by urbanization, with climate change having a relatively small influence. The second essay explores the optimal time path of carbon sequestration and carbon abatement in stabilizing CO₂ levels under uncertainty of climate impacts. We question the conventional wisdom that carbon sequestration should be used as a near term strategy by recognizing the fact that sequestration, unlike abatement, can actually remove CO₂ from the atmosphere. Two related models are examined: a deterministic fixed end point and finite time horizon model and a two-period sequential decision making model. In the latter, uncertainty regard the stabilization level of the atmospheric stock is resolved prior to the decision on how much to control the stock in the second period. Present value costs of abatement and sequestration are minimized subject to two state variables; the level of CO₂ stock in the atmosphere and the stock of suitable land that can be converted to forestland. Both models show that carbon sequestration may play an important role in climate change mitigation under certain conditions. In addition, the stochastic model finds that an increase in the variability of climate impacts results in higher rates of abatement today while leaving some sequestration capacity as a safety value for the future. In the third essay, a structural model of the demand for and the supply of urban land is estimated using panel data on 3032 counties in the contiguous U.S for the four time periods 1982, 1987, 1992 and, 1997. A two-step estimation procedure is applied. In the first step, fixed effects and time-varying variables are used to estimate the structural system of demand and supply equations via Two-Stage Least Squares (2SLS) procedure. This yields consistent estimates of the structural equations' parameters. The model is then extended to a hierarchical linear model. The contribution of observed time-invariant variables in explaining counties fixed effects is investigated. Among these variables are climatic and geographical variables that are assumed to affect both the supply and the demand for urban land, though in potentially different ways. Results suggest inelastic supply and demand at the national and regional levels with the exception of an elastic demand in the West region. Examined climatic and geographical variables are found to have significant effects on both the supply of and the demand for urban land. Title: Three essays on the economics of climate change, land use and carbon sequestration Author: Haim, David This dissertation's three essays explore the effects of climate change on land use changes in the U.S., how future land areas in all major land uses change by projecting land use at the regional scale under two IPCC climate change scenarios. Investigate how and what role should carbon sequestration plays as a mitigation strategy given uncertainty of climate impacts and, estimate how responsive the demand for and the supply of urban land is to changes in its price and how different climatic variables effect both the supply and the demand for urban land. The first essay uses an econometric model to project regional and national landuse changes in the U.S. under two IPCC climate change scenarios. The key driver of land-use change in the model is county-level measures of net returns to five major land uses. The net returns are modified for the IPCC scenarios according to assumed trends in population and income and projections from integrated assessment models of agricultural prices and agricultural and forestry yields. For both scenarios, we project large increases in urban land by the middle of the century, while the largest declines are in cropland area. Significant differences among regions in the projected patterns of land-use change are evident, including an expansion of forests in the Mountain and Plains regions with declines elsewhere. Comparisons to projections with no climate change effects on prices and yields reveal relatively small differences. Thus, our findings suggest that future land use patterns in the U.S. will be shaped largely by urbanization, with climate change having a relatively small influence. The second essay explores the optimal time path of carbon sequestration and carbon abatement in stabilizing CO₂ levels under uncertainty of climate impacts. We question the conventional wisdom that carbon sequestration should be used as a near term strategy by recognizing the fact that sequestration, unlike abatement, can actually remove CO₂ from the atmosphere. Two related models are examined: a deterministic fixed end point and finite time horizon model and a two-period sequential decision making model. In the latter, uncertainty regard the stabilization level of the atmospheric stock is resolved prior to the decision on how much to control the stock in the second period. Present value costs of abatement and sequestration are minimized subject to two state variables; the level of CO₂ stock in the atmosphere and the stock of suitable land that can be converted to forestland. Both models show that carbon sequestration may play an important role in climate change mitigation under certain conditions. In addition, the stochastic model finds that an increase in the variability of climate impacts results in higher rates of abatement today while leaving some sequestration capacity as a safety value for the future. In the third essay, a structural model of the demand for and the supply of urban land is estimated using panel data on 3032 counties in the contiguous U.S for the four time periods 1982, 1987, 1992 and, 1997. A two-step estimation procedure is applied. In the first step, fixed effects and time-varying variables are used to estimate the structural system of demand and supply equations via Two-Stage Least Squares (2SLS) procedure. This yields consistent estimates of the structural equations' parameters. The model is then extended to a hierarchical linear model. The contribution of observed time-invariant variables in explaining counties fixed effects is investigated. Among these variables are climatic and geographical variables that are assumed to affect both the supply and the demand for urban land, though in potentially different ways. Results suggest inelastic supply and demand at the national and regional levels with the exception of an elastic demand in the West region. Examined climatic and geographical variables are found to have significant effects on both the supply of and the demand for urban land. Close

• 2. [Article] Essays on the interactions between land use, natural amenity and wildfire risk

  It is essential to study the relationship between environmental features and human land-use activities that can provide a better understanding of human-environment interactions. In a response, this dissertation ...

  Citation × Citation Citation Abstract Copy Title: Essays on the interactions between land use, natural amenity and wildfire risk Author: Xu, Wenchao It is essential to study the relationship between environmental features and human land-use activities that can provide a better understanding of human-environment interactions. In a response, this dissertation addresses the human-environment issues from different perspectives in three essays. The first essay conducts an integrated analysis to investigate the impacts of human activities and environmental features on wildfire occurrence at the Wildland-Urban Interface in a changing climate. We focus on the impacts of land use changes as measured by their density, connectivity, and mix. The conceptual model builds on a theoretical framework developed by Woodward (1987) and Neilson (1995) that characterizes the functioning mechanism of ecosystems. The empirical models identify the key factors that influence wildfires. Hypotheses are tested to demonstrate the spatial heterogeneity of human land-use impacts on wildfires. Results can inform the design of policies that aim to identify community vulnerabilities, reduce wildfire uncertainties, strengthen firewise community development, and inform future land-use decision making in response to wildfire threats. The second essay analyzes the impacts of wildfire risk on urban development. It builds on and expands the monocentric-city framework developed by Wu (2006) and Wu (2010) by introducing wildfire risk into this model. We calibrate the model and examine the urban spatial profiles changes under different assumptions of wildfire risks and natural amenities. We find that wildfire risk can take on various aspects of urban spatial profiles at a much broad scale that go beyond the fire-prone areas and affects both households and public decision sectors. Even without inconsistency in fire-zone designation policy, over-development can occur in fire-hazardous area. The third essay models the role of amenity in interregional migration and spatial distribution of economic activities. Extending the new economic geography model of Helpman (1998) by including locational amenities, we present a multi-market equilibrium framework that includes consumption, production, and trade. Results suggest that the effects of amenities are significantly affected by household preferences, trade barriers, and other regional economic characteristics. This study contributes to the amenity-driven migration literatures and informs the debate about the effect of amenities on interregional migrations and regional economic development. Title: Essays on the interactions between land use, natural amenity and wildfire risk Author: Xu, Wenchao It is essential to study the relationship between environmental features and human land-use activities that can provide a better understanding of human-environment interactions. In a response, this dissertation addresses the human-environment issues from different perspectives in three essays. The first essay conducts an integrated analysis to investigate the impacts of human activities and environmental features on wildfire occurrence at the Wildland-Urban Interface in a changing climate. We focus on the impacts of land use changes as measured by their density, connectivity, and mix. The conceptual model builds on a theoretical framework developed by Woodward (1987) and Neilson (1995) that characterizes the functioning mechanism of ecosystems. The empirical models identify the key factors that influence wildfires. Hypotheses are tested to demonstrate the spatial heterogeneity of human land-use impacts on wildfires. Results can inform the design of policies that aim to identify community vulnerabilities, reduce wildfire uncertainties, strengthen firewise community development, and inform future land-use decision making in response to wildfire threats. The second essay analyzes the impacts of wildfire risk on urban development. It builds on and expands the monocentric-city framework developed by Wu (2006) and Wu (2010) by introducing wildfire risk into this model. We calibrate the model and examine the urban spatial profiles changes under different assumptions of wildfire risks and natural amenities. We find that wildfire risk can take on various aspects of urban spatial profiles at a much broad scale that go beyond the fire-prone areas and affects both households and public decision sectors. Even without inconsistency in fire-zone designation policy, over-development can occur in fire-hazardous area. The third essay models the role of amenity in interregional migration and spatial distribution of economic activities. Extending the new economic geography model of Helpman (1998) by including locational amenities, we present a multi-market equilibrium framework that includes consumption, production, and trade. Results suggest that the effects of amenities are significantly affected by household preferences, trade barriers, and other regional economic characteristics. This study contributes to the amenity-driven migration literatures and informs the debate about the effect of amenities on interregional migrations and regional economic development. Close