abstract: This dissertation explores vulnerability to extreme heat hazards in the Maricopa County, Arizona metropolitan region. By engaging an interdisciplinary approach, I uncover the epidemiological, historical-geographical, and mitigation dimensions of human vulnerability to extreme heat in a rapidly urbanizing region characterized by an intense urban heat island and summertime heat waves. I first frame the overall research within global climate change and hazards vulnerability research literature, and then present three case studies. I conclude with a synthesis of the findings and lessons learned from my interdisciplinary approach using an urban political ecology framework. In the first case study I construct and map a predictive index of sensitivity to heat health risks for neighborhoods, compare predicted neighborhood sensitivity to heat-related hospitalization rates, and estimate relative risk of hospitalizations for neighborhoods. In the second case study, I unpack the history and geography of land use/land cover change, urban development and marginalization of minorities that created the metropolitan region's urban heat island and consequently, the present conditions of extreme heat exposure and vulnerability in the urban core. The third study uses computational microclimate modeling to evaluate the potential of a vegetation-based intervention for mitigating extreme heat in an urban core neighborhood. Several findings relevant to extreme heat vulnerability emerge from the case studies. First, two main socio-demographic groups are found to be at higher risk for heat illness: low-income minorities in sparsely-vegetated neighborhoods in the urban core, and the elderly and socially-isolated in the expansive suburban fringe of Maricopa County. The second case study reveals that current conditions of heat exposure in the region's urban heat island are the legacy of historical marginalization of minorities and large-scale land-use/land cover transformations of natural desert land covers into heat-retaining urban surfaces of the built environment. Third, summertime air temperature reductions in the range 0.9-1.9 °C and of up to 8.4 °C in surface temperatures in the urban core can be achieved through desert-adapted canopied vegetation, suggesting that, at the microscale, the urban heat island can be mitigated by creating vegetated park cool islands. A synthesis of the three case studies using the urban political ecology framework argues that climate changed-induced heat hazards in cities must be problematized within the socio-ecological transformations that produce and reproduce urban landscapes of risk. The interdisciplinary approach to heat hazards in this dissertation advances understanding of the social and ecological drivers of extreme heat by drawing on multiple theories and methods from sociology, urban and Marxist geography, microclimatology, spatial epidemiology, environmental history, political economy and urban political ecology. / Dissertation/Thesis / Ph.D. Environmental Social Science 2013

Cette étude porte sur la vulnérabilité de la population haïtienne face aux conséquences des changements climatiques. En effet, elle cherche à comprendre la construction de la vulnérabilité socio-économique des producteurs de riz de Fort-Liberté et la manière dont l’État est impliqué pour rendre possible cette construction. Elle s’efforce de décortiquer le contexte d’exposition de la population haïtienne, celle de Fort-Liberté, en particulier, face aux conséquences des changements climatiques associés aux paramètres politiques, socio-économiques, environnementaux, géopolitiques et historiques auxquels les producteurs locaux sont confrontés depuis plus d’une décennie. En donnant la priorité au processus de construction de la vulnérabilité décrit par le modèle de PAR de Ben Wisner (2004), l’accent est mis sur les diverses conséquences d’application du programme d’ajustement structurel (PAS) en Haïti. Conceptuellement, l’étude convoque les discussions controversées sur le développement du concept de vulnérabilité en précisant son évolution épistémique en rapport à la notion du risque. La distinction est clairement faite sur ce que veut dire la vulnérabilité du point de vue des naturalistes, des promoteurs des sciences sociales et les structuralistes. Son sens physico-social a été aussi développé par rapport aux enjeux multiformes qu’engendrent les changements climatiques dans les pays moins avancés, même s’il partage d’importantes similitudes avec les paradigmes classiques et sociaux de la vulnérabilité. Dans le cadre de ce travail, nous avons utilisé les techniques de recherche liées aux groupes de discussion et des entretiens individuels. Dans les deux cas, les entretiens conduits ont privilégié les approches directive et semi-directive. Pour mieux décortiquer les informations, nous avons d’abord effectué une analyse documentaire suivie d’une analyse de contenu liée aux données de terrain. En termes des résultats, nous sommes parvenus à comprendre que les producteurs agricoles de Fort-Liberté sont très exposés aux divers effets néfastes des changements climatiques, notamment de fortes pluies et des périodes de sécheresse répétées. Depuis l’année 2010, la culture rizicole des producteurs de Fort-Liberté enregistre d’importantes baisses de rendement, dans la mesure où, hormis la présence de nouvelles maladies ravageuses, presque toutes les principales rivières alimentant les plantations de riz dans cette commune sont aujourd’hui à leur niveau d’étiage le plus sévère et enregistrent rarement de pluies intenses inondant les espaces habitables et culturaux des producteurs. L’exposition des producteurs aux changements climatiques est exacerbée par l’ampleur du désengagement de l’État à travers les institutions politiques et sociales à protéger ou à accompagner les producteurs dans leurs activités agricoles entre autres. Le désengagement de l’État ne fait que créer des espaces pour une nouvelle forme de développement et de gouvernance qui s’appuie sur une importance accrue des ONG internationales où leur implication dans le secteur du riz ne fait que renforcer celles qui constituent déjà un énorme levier économique en laissant les producteurs dans leur état initialement marginal. Le plus important à cerner dans cette étude, c’est que la problématique de la filière de riz à Fort-Liberté se situe aussi dans le rapport de pouvoir entre les pays occidentaux, notamment entre les États-Unis et Haïti annulant les tarifs douaniers protégeant les productions nationales, le riz en particulier. C’est ce qui explique la transformation du marché de riz des producteurs de Fort-Liberté mais aussi leur cadre de vie. C’est pourquoi la plus grande majorité des producteurs interrogés soutiennent, hormis les aspects qui seront abordés dans le cadre de ce travail de recherche, que l’un des plus grands problèmes de la filière résulte de la concurrence déloyale entre le niveau de production de riz national et la présence de riz étasunien sur le marché haïtien. / This study focuses on the vulnerability of the Haitian population to the consequences of climate change. It helps to understand the construction of the socio-economic vulnerability of rice producers in Fort-Liberté and the way in which the State is involved in making this construction possible. In part, it unravels the context of exposure of the Haitian population, particularly that of Fort-Liberté, to the consequences of climate change associated with the historical political or geopolitical parameters that local producers have faced for over a decade. Focusing on the vulnerability construction process described by Ben Wisner's (2004) PAR model, the focus is on the various consequences of the application of the structural adjustment program (SAP) in Haiti. Conceptually, the study also sheds light on the controversial discussions on the development of the concept of vulnerability by clarifying its epistemic evolution in relation to the notion of risk. A clear distinction is made between what vulnerability means from the point of view of naturalists and social science proponents. Its physical-social meaning has also been developed in relation to the multifaceted challenges posed by climate change in less developed countries, even though it shares important similarities with the classical and social paradigms of vulnerability. Methodologically, we used focus group research techniques and individual interviews. In both cases, the questions asked were, among others, directive and semi-directive in nature. In order to better dissect the information, we first conducted a documentary analysis followed by a content analysis linked to the field data. In terms of results, we can understand that the agricultural producers of Fort-Liberté are very exposed to the various harmful effects of climate change, particularly heavy rains and repeated droughts. Since 2010, the rice crop of Fort-Liberté farmers has experienced a significant drop in yields, insofar as, apart from the presence of new devastating diseases, almost all of the main rivers feeding the rice plantations in this commune are now at their most severe low-water levels and rarely record intense rainfall that floods the farmers' living and cultivation areas. According to the objectives set by the research, the exposure of producers to climate change is exacerbated by the extent to which the State, through its political and social institutions, has disengaged from protecting or accompanying producers in their agricultural and other activities. The disengagement of the state has created more and more space for the emergence of the Western mode of development based generally on the practices of nongovernmental organizations, where their involvement in the rice sector only strengthens those who already have enormous economic leverage by leaving producers in their initially marginal state. The most important thing to understand in this study is that the problem of the rice sector in Fort-Liberté also lies in the power relationship between western countries, particularly between the United States and Haiti, which cancels the customs tariffs protecting national production, particularly rice. This explains the transformation of the rice market of the producers of Fort-Liberté and also their living environment. This is why most of the producers interviewed maintain, apart from the aspects listed above and in the body of the work, that one of the greatest problems in the sector is the unfair competition between the level of national rice production and the presence of US rice on the Haitian market.

Ethiopia is an agrarian country dominated by subsistence farming which is highly vulnerable to climate change. This study was therefore carried out to assess smallholder farmers’ perceptions of climate change and adaptation strategies followed to prevent vulnerability to climate change in the Medium and Upper highlands of the Amhara region of Ethiopia. Data was collected from 300 sample smallholder farmers using questionnaire, key informant interviews, and Focus Group discussions with farmers and experts. The survey result showed that households differ in terms of asset endowments, vulnerability, and coping and adaptation capability to climate change. About 87.3% noticed climatic change and their perception of climatic variable attributes indicated about 75% felt a decline in the amount of rainfall, 52.6% stated early onset, about 66.6 % showed late on set, 84% expressed poor distribution of rainfall, high temperature (83.7%) and desiccating wind (52.7%). The major adaptation strategies employed by the majority of small holder farmers included enhancing traditional irrigation, use of drought tolerant and early maturing varieties, converting farm land to tree growing and relay cropping immediately after harvesting. The coping strategies to climate variability are largely related to migrating to urban areas, engaging in daily work, selling of fuel wood and asset while mitigation measures have focused on ecosystem rehabilitation. “Multi Nominal Logit” (MNL) model analysis indicated gender, education, off farm activity, farm size, ownership of oxen, farmer to farmer extension, access to credit and information on climate change as determinants of adaptation to climate change and variability. Institutional support to farmers’ efforts to adapt to climate change is generally weak. The overall analysis leads to conclude that despite the presence of awareness on climate change and its likely impacts on livelihoods of the smallholder farmer, development intervention at local level are not systematically designed to address the problems of the resource poor farmers and environmental challenges. In the immediate future there is an urgent need to capitalize on existing awareness, document, package and disseminate successful adaptation interventions to farmers. As a long term solution it is recommended that institutions in charge of climate change need to develop a national drought and climate change management strategic plan with full accountability to facilitate ecosystem development, resilience against climate change and ultimately improvements in the livelihood of farmers. Such interventions could potentially be achieved by taking practical measures on policy support and Institutional building for climate change, knowledge management on adaptation to climate change, filling technological gaps related to agriculture including livestock husbandry in the context of climate change, applying innovative local level participatory land use planning and promoting livelihood diversification initiatives that could enable small holder farmers create assets to enhance their livelihoods. / Environmental Sciences / D. Phil. (Environment Management)