Thesis (M. Hous. M.)--University of Hong Kong, 2008. / Includes bibliographical references (leaf 76-77)

Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 264-277). Also available in print.

Thesis (M. Hous. M.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 70-73).

Thesis (M.Hous.M.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 70-73) Also available in print.

Thesis (M. Hous. M.)--University of Hong Kong, 2007.

Hydrothermal circulation at mid-ocean ridges plays an important role in the interaction between oceanic lithosphere and the overlying ocean. Changes in fluid flux within hydrothermal systems may directly impact ocean circulation, temperature, and chemistry, and hence the lives of biological organisms in hydrothermal vent environments. The permeability structure within a hydrothermal environment is an important control on fluid flow throughout the system. Common suggestions for mechanisms that might increase permeability within the system include thermal cracking due to contraction of the hot rock from interaction with cold seawater, fluid pressure of the water moving through the rock, tectonics, or tidal forces. Additional factors such as mineral precipitation can decrease permeability in the system, further complicating the permeability structure. Though there are many factors to consider within a hydrothermal system, few quantitative studies of these cracking mechanisms exist. This study examines the role of thermal cracking near hydrothermal vents via a numerical model created in Matlab. Flow was modeled using the Laplace equation, and the heat transfer equation was used to determine temperature differences in the rock, which lead to thermal cracking. The numerical results were compared with microearthquakes observed by Tolstoy et al. (2008) near a hydrothermal vent field along the East Pacific Rise. The model suggests that thermal cracking does occur, and this cracking occurs within the area of microearthquakes observed. Though thermal cracking is important for increasing permeability within the system, there are no obvious spatial or temporal trends within the earthquake data that support a direct relation between the modeled thermal cracking and observed earthquakes. It is likely that the observed earthquakes are due to a combination of cracking mechanisms, such as cracking due to fluid pressure, tectonics, or tides, in addition to the modeled thermal stresses.

Magister Artium - MA

In environmental terms, New Orleans is a city that should not exist. With the Mississippi River eager to escape its engineered confinement, the topography of the city sinking slowly due to subsidence, and the steady rise of sea level partnered with wetland and coastal erosion, the future of New Orleans is wet and it is fast approaching. Initial settlers built on the naturally elevated sediment deposits of the Mississippi River, but over time and as the city grew, swamps were drained and occupation spread into lower, more saturated ground. For over two hundred years, humans have interfered with water's natural authority over this area. We have contained, diverted, drained, and regulated rivers, lakes, and swamps to maintain a constructed version of the ground plane that subverts natural processes to the regions' detriment. Plans for the future of New Orleans have been debated since Hurricane Katrina served as an expose to our synthesized and extremely fragile system. From the Dutch Dialogues, a comprehensive u an redevelopment plan, to smaller scale water management studies such as the Mirabeau Water Gardens, the drawing board has rarely been empty. Proposals have met resistance from the community, and ten years after the disaster, no coherent plan has been outlined. New Orleans isn't the only city searching for answers; delta and coastal cities the world over are recognizing the need to rethink resiliency and sustainability in light of global environmental changes. This project proposes neighborhood-scale interventions that bring previously concealed water processes to light by exhibiting them in a sustainable community-centered resource. Rather than altering existing infrastructure, this strategy would utilize current neutral ground conditions in order to take pressure off the City's drainage network. By accepting and accommodating water within the urban fabric, New Orleans can address the deficiencies in defensive water infrastructure to define a new resilience. / 0 / SPK / specialcollections@tulane.edu

While repeated transgressive and regressive sea level cycles have shaped south Florida throughout geological history, modern rates of sea level rise pose a significant risk to the structure and function of the freshwater wetland ecosystems throughout the low-lying Everglades region. Current regionally corrected sea level projections for south Florida indicate a rise of 0.42m by 2050 and 1.15m by 2100, suggesting the salinization of previously freshwater areas of the Everglades is conceivable. As freshwater areas become increasingly exposed to saltwater they experience shifts in vegetation composition, soil microbial populations, plant productivity, and physical soil properties that ultimately result in a phenomenon called peat collapse. Recent work in the Everglades has sought to further explain the mechanisms of peat collapse, however the physical changes to the peat matrix induced by saltwater intrusion are still uncertain. Moreover, the combination of physical alterations to the peat matrix associated with peat collapse and shifts in wetland salinity regimes will also likely disrupt the current carbon gas dynamics of the Everglades. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection

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.