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Tropical cyclone (TC) size is integral in determining the spatial extent of TC impacts and is influenced by environmental wind shear and the overall moisture environment. Since initial TC size is related to future TC size, research focused on understanding the influences of TC size away from land can lead to a more complete understanding of the extent of coastal impacts associated with landfalling TCs. This study considers TCs located in an area of low to moderate wind shear located at least 100 km from major land masses. An empirical orthogonal function (EOF) analysis is used to distinguish different environments based on the large-scale spatial pattern of total column water vapor (TCWV) surrounding the TC. Using these EOF patterns, four separate categories (groups) are created. Principal component (PC) scores indicate the time steps most contributing to the EOF pattern for each group and ultimately determine the time steps included in each group. TC sizes among the groups are compared using size metrics based on the wind field and shape metrics based on the precipitation field. These metrics are considered at the central timestep identified in the EOF analysis as well as a 48-hour window centered on the central timestep. There are no significant differences in the wind field size, but TCs with moisture to the southeast are the largest in terms of overall precipitation area. This suggests that moisture affects the size of the precipitation field but not the wind field. However, more research is needed to confirm this relationship. Storms with moisture to the southeast are also more intense and younger than TCs in other groups and show signs of inner core organization and subsequent intensification while TCs in the other groups do not. TCs in an extremely dry environment or with dry air to the southeast of the TC center are generally smaller, less closed, less solid, and older than TCs with moisture to the southeast and TCs with dry air to the northwest of the TC center. An additional analysis comparing the same size and shape metrics between TCs experiencing easterly and westerly shear is also completed. The wind shear results suggest that, while easterly shear is more commonly associated with younger and intensifying TCs regardless of moisture group, an environment with westerly shear is more favorable for intensification of TCs with moisture to the southeast due to the alignment of moisture and upward motion. Future work will investigate the physical processes contributing to these precipitation shape and size differences between groups and wind shear directions. Master of Science The size of tropical cyclones (TCs) is heavily influenced by moisture and wind shear. Wind shear is defined as the changing of wind direction with vertical height in the atmosphere. Research focused on investigating how moisture and wind patterns affect the size and structure of TCs can lead to a better understanding of the physical extent of impacts associated with landfalling TCs and advise more effective emergency preparedness plans. This research considers TC time steps located over the ocean and in a calm wind environment. From here, time steps are divided into four groups representing common moisture patterns in the Atlantic basin. TC size is evaluated using size and shape metrics designed to capture the spatial extent and layout of wind and rain associated with the storm. This research also compares the evolution of these size and shape metrics to better understand how the environment around the TC changes over time. Results show that the extent of wind associated with the storm is similar across all groups but TCs with moisture to the southeast are the largest in terms of overall rain area. This suggests that moisture affects the extent of precipitation but not the extent of wind or that wind data are inaccurate. Additionally, TCs with moisture to the southeast are younger and stronger than storms in the other groups. TCs in extremely dry environments and TCs with dry air to the southeast are generally smaller, weaker, and older than TCs in the other groups. In looking at the evolution of these size and shape metrics, TCs with moisture to the southeast group become stronger with time while TCs in the other groups do not. An additional analysis comparing TCs experiencing different wind patterns is completed. Results of this show that, while easterly wind shear, characterized by surface winds out of the west and upper level winds out of the east, is more commonly associated with strengthening TCs when moisture is not considered, TCs with moisture to the southeast in an environment with westerly wind shear are more likely to strengthen over time due to the alignment of moisture with favorable environmental conditions within the storm by the overall wind pattern. Westerly shear is characterized by winds at the surface out of the east and upper level winds out of the west. Future work should focus on the environmental processes contributing to the size and shape differences observed between moisture groups and wind patterns.

Coastal communities along the eastern seaboard are continuously exposed to flooding and related impacts, compromising the health and safety of their residents and especially of more vulnerable older populations. In cases where structural protection and floodproofing measures may not protect households from all types of flooding, relocation may represent the most effective long-term adaptation option. However, the extent to which older residents in Hampton Roads, Virginia are exposed to such flooding is not well understood, nor are the factors influencing their relocation attitudes. Thus, the main objective of this research is to understand both the exposure to flooding and evaluate attitudes towards relocation among older residents in Hampton Roads. This study uses a mixed methods approach to analyze flood exposure and attitudes towards relocation among older adults living in this area. First, a geospatial analysis was conducted to assess the change in flood risk in Hampton Roads over a period of 60 years and exposure to older populations, aged 60 and over. Then the survey data were used to conduct a correlation analysis to examine the relationship between survey responses and respondents' willingness to consider relocation. The geospatial analysis showed that flood exposure in this area does not increase linearly with time, with several block groups experiencing accelerated levels of flood increases from 2000-2060. Most of the municipalities which experience high overlap between flood extent and older population percentages are urban and see dramatic increases in flood exposure from 2000-2060. The statistical results show that willingness to consider relocation is correlated to several variables measuring sociodemographic characteristics, place attachment, and flood exposure, and less to other considerations influencing the decision to permanently relocate. The most influential factors driving relocation attitudes are financial, where residents would consider relocation if compensated or offered similar housing elsewhere. Finally, a large proportion of respondents (40.28%) would prefer to permanently move to either a different region or different state should flooding continue in their community. The results of this study can help community leaders and policymakers to better understand the flood outcomes and assistance needs of their older populations living in flood-prone areas. Master of Science Coastal communities along the Eastern United States are constantly exposed to flooding and related impacts. Hampton Roads, Virginia is experiencing higher-than-average sea level rise, which is increasing flooding and its impacts. This area is also a preferred retirement region, where older populations prefer to move. Older populations are more negatively affected by these impacts due to chronic health conditions like diabetes and hypertension, which require easy access to health care services, as well as mobility constraints. The objective of this research is to identify areas within Hampton Roads that have a significant overlap between flooding and older populations and to understand what factors are affecting older residents' attitudes towards relocation. This study answers the following questions regarding the overall objective: 1) What is the exposure to coastal flooding of older populations living in urban areas in Hampton Roads? and 2) Which aspects of socioeconomic circumstances, experiences with flooding, and flood-related concerns affect attitudes about permanent relocation among older coastal residents? To answer these questions, a geospatial analysis was conducted, followed by a survey analysis. There are high levels of overlap between older populations and flooding in urban municipalities, and flood exposure is expected to dramatically increase between the years 2000 and 2060. From the survey, older respondents favor monetary incentives for relocation as opposed to other factors. The results from this study should be used by local policymakers for more well-informed decisions that incorporate community members in the planning and relocation process.

Coastal flood impacts are increasing in severity with the rising sea levels, causing damage to ecological and human systems. Climate-hazards may also result in cascading impacts, where an initial disaster sets off a chain of events that extends beyond the initial spatiotemporal point of impact. Coastal flood events may result in consecutive disasters in which the initial flood event results in a secondary technological disaster, prompting disruptions to socio-economic systems and resulting in a public health crisis. Flood events that trigger technological emergencies through the inundation and dispersion of hazardous materials are known as Natech disasters. However, current research on the cascading impacts of Natech events is limited. Hampton Roads, Virginia, is experiencing an accelerated rate of sea level rise and a proportionally higher risk of storm surge, potentially leading to a greater risk of Natech disasters. The main objective of this study is to evaluate the impact of Natech events on surrounding communities in Hampton Roads. This study uses geospatial analysis to identify the current (2021) and future (2051) threats of flood-induced Natech disaster and assess its exposure to different coastal populations and ecosystems. The present study calculated the Flood Hazard Density Index (FHDI), using a 1-mile radius around the significantly flooded facilities to determine the spatial dispersion of Natech disasters. The flood risks were determined using the 100-year flood plain and intermediate (RCP 4.5) climate scenario. The risk of a Natech disaster was identified by combining the spatial extent of flood risk with the location of Toxics Release Inventory (TRI) facilities and National Priorities List (NPL) designated Superfund sites. The exposed environmental and social systems to Natech events were chosen through the literature gap analysis. Sociodemographic data from the American Community Survey were collected to examine its correlation with 2021 and 2051 FHDI-affected block groups. Findings reveal that block groups with higher proportions of minorities, people in poverty, and people without a vehicle experience significant exposure to a Natech disaster compared to those who are living further away from the TRI and Superfund facilities. Additionally, open water and wetland environments will also experience significant exposure to Natech events, which could indicate a loss of ecosystem services. This study suggests a need for proactive policy and programmatic interventions to minimize the potential impacts of Natech events on the surrounding communities, such as the remediation of Superfund sites and the development of hazard mitigation plans for TRI facilities. Master of Science Coastal flood impacts are increasing in severity with the rising sea levels, causing damage to ecological and human systems. Climate-hazards may also result in cascading impacts, where an initial disaster sets off a chain of events that extends beyond the initial spatial origin of impact, prolonging the effects of the initial disaster. Coastal flood events may result in consecutive disasters, where an initial flood event results in a secondary technological disaster, prompting disruptions to socio-economic systems and resulting in a public health crisis. Flood events that trigger technological emergencies causing the inundation and dispersion of hazardous materials are known as Natech disasters. However, current research on the cascading impacts of Natech events is limited. Hampton Roads, Virginia, is experiencing accelerated sea level rise and a proportionally higher risk of storm surge, potentially leading to a greater risk of Natech disasters. The main objective of this study is to evaluate the impact of Natech events on surrounding communities in Hampton Roads. This study uses geospatial analysis to identify the current (2021) and future (2051) threats of flood-induced Natech disaster and assess its exposure to different coastal populations and ecosystems. The present study used a 1-mile radius around the significantly flooded facilities to determine the spatial dispersion of Natech diasters. The flood risks were determined using the 1 in 100 annual flood risk and an intermediate climate projection. The risk of a Natech disaster was identified by combining the spatial extent of flood risk with the location of U.S. Environmental Protection Agency (U.S. EPA) regulated Toxics Release Inventory (TRI) facilities and National Priorities List (NPL) designated Superfund sites. The most susceptible social, economic, and environmental subsystems to Natech events were identified using a literature gap analysis. Sociodemographic data were collected from the American Community Survey to examine its relationship to the 2021 and 2051 Natech affected census block groups. Findings reveal that block groups with higher proportions of minorities, people in poverty, and people without a vehicle experience significant exposure to a Natech disaster compared to those who are living further away from the TRI and Superfund facilities. Additionally, open water and wetland environments will also experience significant exposure to Natech events, which may indicate a loss of ecosystem services. This study suggests a need for proactive policy and programmatic interventions to minimize the potential impacts of Natech events on the surrounding communities, such as the remediation of Superfund sites and the development of hazard mitigation plans for TRI facilities.

Coastal communities face threats of flooding associated with episodic storm events and high tides that are increasing in severity and frequency due to climate change and sea level rise (SLR). The Mid-Atlantic U.S. is experiencing SLR at rates faster than the global average, especially in Hampton Roads, Virginia where the rate of SLR is accelerating due to land subsidence. Adaptation plans for coastal flooding are mostly made at the municipality level, ignoring the propagation of water across its administrative boundaries. Impact assessment at the watershed scale identifies areas where municipalities will need to collaborate to mitigate the flood impact. The main purpose of this project was to evaluate the impact of flooding among watersheds in Hampton Roads and identify those most at risk that overlap one or more municipal boundary. Additionally, this research assessed the impact on land use/cover and population throughout the Hampton Roads region and within a case study watershed. To meet these objectives, we used U.S. Army Corps of Engineers 50-year floodplain and NOAA intermediate SLR scenarios for 2030, 2060, and 2090 to calculate the percent land area inundated for each watershed in Hampton Roads. Further, we assessed the flood impact on populations and specific land use/covers throughout the region for each SLR scenario, as well as within the Elizabeth River watershed. Key findings show that five watersheds will see a greater increase in inundated area than the surrounding watersheds, with two that overlap multiple municipalities. The anticipated land use impacts indicate significant inundation of land occupied by military, followed by commercial, industrial, and wetland covers both in Hampton Roads and within the Elizabeth River watershed. These findings not only highlight the need for more synchronized collaboration on adaptation between municipalities in Hampton Roads, but also provide a framework for the impact assessments in similar settings globally. Master of Science Coastal communities face numerous threats of flooding due to storm events and high tides. These events are becoming more frequent due to climate change and sea level rise (SLR). The Mid-Atlantic U.S. is experiencing SLR at rates faster than the global average, especially in Hampton Roads, Virginia where the rate of SLR is accelerating due to sinking land. Water movement does not recognize administrative boundaries but rather reflects physical features of the land. At the same time most plans to combat rising water levels are often made within administrative boundaries. The main objective of this research is to evaluate the flood impacts at the watershed scale and identify areas where localities will need to collaborate to reduce flood impact. This research further explores answers the following questions: 1.)Which watersheds in Hampton Roads are most prone to flooding?; and 2.) How many people will be impacted by flooding, and what kinds of land uses will be impacted? To answer these questions, we used floodplain data and SLR scenarios for 2030, 2060, and 2090 to determine land area inundated for each watershed in Hampton Roads. Further, we summarized population and land use impacts within the floodplain for the entire region, as well as within a case study of the Elizabeth River watershed in Norfolk and Portsmouth. Key findings include five watersheds that will see a greater increase in inundated area with SLR than surrounding watersheds, two of which contain multiple municipalities. Finally, we identified significant impacts for military, commercial, industrial, and wetland land covers both in Hampton Roads and within the Elizabeth River watershed.

Climate services, often refers as decision support tools, are developed to provide information with a view to aid in decision making and policy planning for adaptation due to climate variability and change. This study investigated different publicly available climate services and decision support tools based on previously proposed evaluation framework. This evaluation framework originally consists of four design elements which are divided into nine evaluation metrics for this study. These evaluation metrics are: identification of decision making context, discussion of the role of climate information in decision making, discussion of non-climatic factors, uncertainty of the data presented, accessibility of information, discussion on the development process, sustainability/ ongoing process, discussion of funding sources, and evaluation of the tool through survey, modeling or contingent valuation method. Tools were then given "High", "Medium", and "Low" score for each of the criterion. A total of 19 tools were evaluation for this study. Tools performed relatively well in "characteristics, tailoring, and communication of the climate information" and "governance, process, and structure of the climate service" whereas they got average scores in "problem identification and the decision-making context" and "value of the service provided". Additionally, four case study evaluation of tools showed detail evaluation of how the tools performed against each of the criterion. The results of this study showed the relative strengths and weakness of the evaluated tools which can be used to improve existing climate services to aid in adaptation decision needs for climate change. This will also help in better decision making and policy planning for different sectors impacted by the changing climate. Master of Science Climate services, often refers as decision support tools, are developed to provide information with a view to aid in decision making and policy planning for adaptation due to the adverse impacts caused by climate variability and change. This study investigated a total of 19 publicly available climate services and decision support tools based on previously proposed evaluation framework. This evaluation framework originally consists of four design elements which further classified into nine evaluation metrics and each of tools were given "High", "Medium", and "Low" score against these criteria. These metrics are: identification of decision making context, discussion of the role of climate information in decision making, discussion of non-climatic factors, uncertainty of the data presented, accessibility of information, discussion on the development process, sustainability/ ongoing process, discussion of funding sources, and evaluation of the tool through survey, modeling or contingent valuation method. Evaluated tools performed better than average in terms of uncertainty of the data presented, accessibility of information, discussion on the development process, sustainability/ ongoing process, discussion of funding sources, and feedback/ evaluation criteria whereas they performed below average in problem identification and decision making context, discussion of the role of climate information in decision making, and discussion of non-climatic factors. Four case study evaluation were also presented in this study for better understanding of how the evaluation process works for the tools. The results of this study provide an insight about the relative strengths and weakness of the evaluated tools and these can be used to improve existing climate services tools. This will also help in better decision making and policy planning for different sectors that are being impacted by the changing climate.

Evaluating and educating communities on their flood risks is an integral part of adapting to climate change and more extreme precipitation patterns. Low-income communities are often the most affected by in-land floods. They are more likely to live in floodplains and have less socioeconomic mobility. This thesis takes a two-pronged approach to evaluating flood risk. First, a flood risk model that identifies areas of high runoff in Giles County, Virginia was developed. The model accounts for land cover, soil type and elevation. The soil retention layer and Digital Elevation Model (DEM) produced a cell by cell layer of runoff. Storm data was collected from the NEXRAD program and integrated into the runoff layer. Countywide maps of low, moderate and high risk were produced. Semi structured interviews were then conducted to gauge the usability of the maps within high risk areas. Interview feedback was transcribed and coded for analysis. Themes identified throughout the interviews, were used to make adjustments to the model and maps. This experience suggests that combining technical analysis and community engagement can create a more accurate depiction of flood risk that is meaningful to those most affected. This paper also suggests that evaluating riverine flooding based on the most severe, recent storm yields a more accurate and impactful tool than previous flood modeling methods. This work takes flood modeling a step farther by receiving community input and shows that models are only as useful as they are meaningful to the most impacted communities. Master of Urban and Regional Planning Climate change models suggest that many communities will experience fewer precipitation events, but when precipitation events do occur they will be more intense and thus destructive. Communities can expect a higher risk of flooding, which is why it is important to plan proactively and understand where the most at-risk areas are. To help Giles County, VA understand its flood risk we created a tool that displays storm runoff. Elevation, soil type and vegetation were incorporated into the model. Storm data was integrated into the model and compared to annual precipitation levels. Countywide maps of low, moderate and high risk were produced. In order for the maps to have the maximum impact they need to be accessible to at risk populations. To gauge the accessibility of the maps to the community semi structured interviews were conducted within the high risk areas. Issues and opportunities identified through the interviews were used to make adjustments to the model and maps. The findings suggest that combining technical analysis and community engagement can create more accurate depictions of flood risks that are meaningful to those most affected. Future research efforts should include incorporating anticipated development schemes into the model and hosting more in depth community engagement activities. The importance of community engagement is highlighted in this research, as the interviews has a major impact on the outcome of the model.

This project deploys a modified Water Poverty Index (WPI) in villages reconstructed after the 2004 tsunami in southeastern India. While previous measurements of access to water have advanced understandings of waterscape complexities, this modified WPI improves past efforts and deconstructs some of the previous misunderstandings and notions regarding access to water. The traditional WPI is multidimensional and seeks to measure water access in a holistic fashion; the WPI presented here employs this approach, but is adapted to include new place-based indicators (e.g., Secondary Sources). Furthermore, unlike previous iterations of the WPI, our modified index incorporates water quality testing, three weight schemes, and operates at several scales. Ultimately, the construction and arrangement of our modified WPI enables statistical analyses, geospatial analyses, and water poverty mapping -- which are absent in most prior studies-- while still remaining easy to populate and descriptively analyze among non-academicians. Statistical tests of original household level data from a total of 24 villages in Nagapattinam District, Tamil Nadu, and Karaikal District, Puducherry, indicate significant differences between the two districts in indicator scores as well as total WPI score. Additionally, the urban and rural areas within each district were found to be significantly different in level of water poverty, and trends were similar across the three weight schemes. Multiple linear regressions show correlation of independent socioeconomic variables (i.e., Income, Education, and Assets-Networks) with the dependent indicator of Capacity, but not with the other indicators or total WPI score. Global Moran's I tests indicate positive spatial autocorrelation, demonstrating that indicator and WPI scores tend to cluster in space. Overall, the results match what was anticipated, yet serve to challenge commonly held assumptions on urban-rural hierarchies and the role of socioeconomic variables in determining water poverty. The construction, deployment, and analytical potential of this modified WPI can be used by scholars to improve existing conceptualizations and measurements of access to water, while the results can be used by local governments and nonprofits to improve resource allocation and inform spatially-targeted interventions. Master of Science