<p>This MSc thesis contributes with new information on how vulnerability to tropical cyclone (TC) induced flooding has evolved at two coastal lowland study sites in the town of Corinto in Nicaragua over a period of 50 years. The research was done through rain station data analyses, semi-structured interviews, and focus group discussions. Analyses of changing poverty, human mobility, housing conditions, and occurrence of flood-related diseases were used as additional indicators supporting the overall vulnerability assessment.</p><p>The recent increase in the North Atlantic TC activity can not be seen in the data from Corinto. The both studied neighborhoods built on dump-sites and mangrove marsh have clearly become less exposed, less sensitive, and more resilient to external stress brought by TCs. These two sites have been developing into different directions since one has reached a more prosper status whereas the other is still rather marginal. The former has been supported by the local government while the latter has been growing in a less regulated way.</p><p>This thesis suggests that there are coastal communities in developing countries, which are able to cope with and adapt to extreme climate events even though this kind of vulnerability has been predicted to increase due to global warming.</p>

This MSc thesis contributes with new information on how vulnerability to tropical cyclone (TC) induced flooding has evolved at two coastal lowland study sites in the town of Corinto in Nicaragua over a period of 50 years. The research was done through rain station data analyses, semi-structured interviews, and focus group discussions. Analyses of changing poverty, human mobility, housing conditions, and occurrence of flood-related diseases were used as additional indicators supporting the overall vulnerability assessment. The recent increase in the North Atlantic TC activity can not be seen in the data from Corinto. The both studied neighborhoods built on dump-sites and mangrove marsh have clearly become less exposed, less sensitive, and more resilient to external stress brought by TCs. These two sites have been developing into different directions since one has reached a more prosper status whereas the other is still rather marginal. The former has been supported by the local government while the latter has been growing in a less regulated way. This thesis suggests that there are coastal communities in developing countries, which are able to cope with and adapt to extreme climate events even though this kind of vulnerability has been predicted to increase due to global warming.

This paper examines the possible contribution of evolutionary economics to macro-economic modelling of flood impacts to provide guidance for future economic risk modelling. Most macro-economic models start from a neoclassical economic perspective and focus on equilibrium outcomes, either in a static or dynamic way, and describe economic processes at a high level of aggregation. As a consequence, they typically fail to account for the complexity of social interactions and other behavioural responses of consumers and producers to disasters, which may affect the macroeconomic impacts of floods. Employing evolutionary principles and methods, such as agent-based modelling, may help to address some of the shortcomings of current macro-economic models. We explore and discuss the implications of applying consumer and producer heterogeneity, bounded rationality, network effects, social and technological learning, co-evolution and adaptive policy-making concepts into existing economic frameworks for the assessment of macro-economic impacts of floods. (authors' abstract)

Kashechewan, a flood-prone remote First Nation in northern Ontario, is the focus of this thesis. It is an exploration into the factors that have contributed to the community’s decline and current state. By looking at how these factors influence built form, the principles, possibilities, and concepts that are latent within it are used to re-establish ways in which the people can view, value, and act upon the land to create lasting change. The discussion has larger implications about how we, as Canadians, live with the land and built forms, and react to one another both as a collective, and as individuals. It is an attempt to dissolve the distinction between ‘aboriginal’ and ‘colonizer’ to open up greater design possibilities. Composed as a series of explorations into the physical and spiritual form of the community, this thesis weaves together three parts of its larger story connected with the thread of narrative poem. Part I opens a discourse that considers the impact of the system and establishment of Aboriginal Reserves on the community. Part II explores the notion of remoteness alongside methods of movement and transportation of people and materials. Part III engages the ephemeral, discussing memory and the meaning of transient moments. Stemming from these streams of exploration, three individual designs are proposed. The first explores flood-resilient architecture as a sensitive response to the river and engages the future expansion of the community beyond the walls of the dike. The second envisions an integration of movement into a centralized community hub. The third lays out an approach to abandoning the site while preserving its sacred spaces. In each case, the design explores built form as a tool for fusing back together the spirit of the land and the narrative of the people. Through the metaphor of flooding as a conversation between the light and the dark, this thesis looks at the history of abuse between aboriginal and colonizer, and the current abuse of substance and soul from which an architectural premise moves forward. The thesis attempts to embrace the complexity and difficulty of designing with such inherent obstacles to overcome by taking inspiration from the simple and sublime beauty of the place and distilling it into built form.

Flooding inundation during hurricanes has been very costly and dangerous. However, the impact of climate change on hurricane flooding is not well understood at present. As sea surface temperatures increase, it is expected that hurricane intensity will increase and sea levels will rise. It is further hypothesized that climate change will increase hurricane flooding inundation, which would increase property damages and adversely affect a greater number of people. This thesis presents a case study of Corpus Christi, Texas, which analyzes the impact of climate change on hurricane flooding. Sea level rise projections and intensification of historical hurricanes were considered in this study. Storm surges were determined with the ADCIRC numerical model, while GIS was used to estimate area flooded, property damages, and population affected. Flooding inundation, property damages, and number of people affected by flooding increases as the intensity of the hurricane increases. As hurricane intensity increases and sea levels rise, the depth of flooding also increases dramatically. Based on two historical hurricanes and one shifted historical hurricane, on average the inundated area increases about 11 km2 per degree Celsius of sea surface temperature rise, the property damages increase by about $110 million per degree Celsius of sea surface temperature rise, and the number of people affected by flooding inundation increases by about 4,900 per degree Celsius of sea surface temperature rise. These results indicate that it may become necessary to consider the effects of climate change when building future coastal communities and adapting the protection of existing communities.

In a counter-current two-phase flow system, flooding can be defined as the onset of flow reversal of the liquid component which results in an upward co-current flow. Flooding in the surge line of pressurized water reactors poses a significant technical challenge in the analysis of several postulated nuclear reactor accident scenarios. Despite the importance of flooding in these analyses, previous work does not identify a universally accepted rigorous physics-based model of flooding, even for the simple case of flooding in adiabatic, vertical tubes. This can be attributed to a lack of conclusive understanding of the physics of two-phase counter-current flow, specifically the mechanism of flooding, and the large amount of uncertainty among data from various flooding experiments. This deficiency in phenomenological and experimental knowledge has led to the use of many empirical and semi-empirical correlations for specific system conditions and geometries. The goal of this work is the development of a model for flooding in vertical, adiabatic tubes from first principles. To address a source of uncertainty in the analysis of flooding, a model for the prediction of average film thickness in annular co- and counter-current flows has been developed by considering the conservation of momentum of the liquid and gas flows. This model is shown to be a quantitative improvement over the most commonly used models, those of Nusselt and Belkin, Macleod, Monrad, and Rothfus. The new model better considers the effects of interfacial shear and tube curvature by using closure relations known to represent forces appropriately in co- and counter-current flow. Previous work based on semi-empirical flooding models has been analyzed to develop a new theory on the hydrodynamic mechanism which causes flooding. It is postulated that the growth of an interfacial wave due to interfacial instability results in a flow reversal to ensure that momentum is conserved in the counter-current flow system by causing a partial or complete co-current flow. A model for the stability of interfacial waves in a counter-current flow system is proposed and has been developed herein. This model accurately represents the geometric and flow conditions in vertical adiabatic tubes and has been shown to have limits that are consistent with the physical basis of the system. The theory of waves of finite amplitude was employed to provide closure to an unknown parameter in the new model, the wave number of the wave that generates the interfacial instabil- ity. While this model underpredicts the flooding superficial gas velocity, the result is a conservative estimate of what conditions will generate flooding for a system. In the context of the analysis of a nuclear reactor, specifically a pressurized water reactor, conservatism means that the gas flow rate predicted to cause flooding for a fixed liquid flow rate will be less than the flow rate found experimentally, mean- ing that liquid delivery to the core would be safely underestimated. Future work includes the improvement of the closure relation for the limiting wave number that will cause unstable interfacial waves, as well as an assessment of the applicability of the stability-based model to flooding in the presence of phase change and flooding in complex geometries.

Since the devastating hurricane seasons of 2004, 2005, and 2008, the stability and serviceability of coastal bridges during and following hurricane events have become a main public concern. Twenty coastal bridges, critical for hurricane evacuation and recovery efforts, in Texas have been identified as vulnerable to hurricane surge and wave action. To accurately assess extreme surges at these bridges, a dimensionless surge response function methodology was adopted. The surge response function defines maximum surge in terms of hurricane meteorological parameters such as hurricane size, intensity, and landfall location. The advantage of this approach is that, given a limited set of discrete hurricane surge data (either observed or simulated), all possible hurricane surges within the meteorological parameter space may be described. In this thesis, we will first present development of the surge response function methodology optimized to include the influence of regional continental shelf geometry. We will then demonstrate surge response function skill for surge prediction by comparing results with surge observations for Hurricanes Carla (1961) and Ike (2008) at several stations along the coast. Finally, we apply the improved surge response function methodology to quantify extreme surges for Texas coastal bridge probability and vulnerability assessment.

Quick evaluation of reservoir performance is a main concern in decision making. Time-consuming input data preparation and computing, along with data uncertainty tend to inhibit the use of numerical reservoir simulators. New analytical solutions are developed for capacitance-resistive models (CRMs) as fast predictive techniques, and their application in history-matching, optimization, and evaluating reservoir uncertainty for water/CO₂ floods are demonstrated. Because the CRM circumvents reservoir geologic modeling and saturation-matching issues, and only uses injection/production rate and bottomhole pressure data, it lends itself to rapid and frequent reservoir performance evaluation. This study presents analytical solutions for the continuity equation using superposition in time and space for three different reservoir-control volumes: 1) entire field volume, 2) volume drained by each producer, and 3) drainage volume between an injector/producer pair. These analytical solutions allow rapid estimation of the CRM unknown parameters: the interwell connectivity and production response time constant. The calibrated model is then combined with oil fractional-flow models for water/CO₂ floods to match the oil production history. Thereafter, the CRM is used for prediction, optimization, flood performance evaluation, and reservoir uncertainty quantification. Reservoir uncertainty quantification is directly obtained from several equiprobable history-matched solutions (EPHMS) of the CRM. We validated CRM's capabilities with numerical flow-simulation results and tested its applicability in several field case studies involving water/CO₂ floods. Development and application of fast, simple and yet powerful analytic tools, like CRMs that only rely on injection and production data, enable rapid reservoir performance evaluation with an acceptable accuracy. Field engineers can quickly obtain significant insights about flood efficiency by estimating interwell connectivities and use the CRM to manage and optimize real time reservoir performance. Frequent usage of the CRM enables evaluation of numerous sets of the EPHMS and consequently quantification of reservoir uncertainty. The EPHMS sets provide good sampling domains and reasonable guidelines for selecting appropriate input data for full-field numerical modeling by evaluating the range and proper combination of uncertain reservoir parameters. Significant engineering and computing time can be saved by limiting numerical simulation input data to the EPHMS sets obtained from the CRMs. / text

The depletion of oil reserves and higher oil prices has made chemical enhanced oil recovery (EOR) methods more attractive in recent years. Because of geological heterogeneity, unfavorable mobility ratio, and capillary forces, conventional oil recovery (including water flooding) leaves behind much oil in reservoir, often as much as 70% OOIP (original oil in place). Surfactant/polymer flooding targets these bypassed oil left after waterflood by reducing water mobility and oil/water interfacial tension. The complexity and uncertainty of reservoir characterization make the design and implementation of a robust and effective surfactant/polymer flooding to be quite challenging. Accurate numerical simulation prior to the field surfactant/polymer flooding is essential for a successful design and implementation of surfactant/polymer flooding. A recently developed unified polymer viscosity model was implemented into our existing polymer module within our in-house reservoir simulator, the Implicit Parallel Accurate Reservoir Simulator (IPARS). The new viscosity model is capable of simulating not only the Newtonian and shear-thinning rheology of polymer solution but also the shear-thickening behavior, which may occur near the wellbore with high injection rates when high molecular weight Partially Hydrolyzed Acrylamide (HPAM) polymers are injected. We have added a full capability of surfactant/polymer flooding to TRCHEM module of IPARS using a simplified but mechanistic and user-friendly approach for modeling surfactant/water/oil phase behavior. The features of surfactant module include: 1) surfactant component transport in porous media; 2) surfactant adsorption on the rock; 3) surfactant/oil/water phase behavior transitioned with salinity of Type II(-), Type III, and Type II(+) phase behaviors; 4) compositional microemulsion phase viscosity correlation and 5) relative permeabilities based on the trapping number. With the parallel capability of IPARS, commercial scale simulation of surfactant/polymer flooding becomes practical and affordable. Several numerical examples are presented in this dissertation. The results of surfactant/polymer flood are verified by comparing with the results obtained from UTCHEM, a three-dimensional chemical flood simulator developed at the University of Texas at Austin. The parallel capability and scalability are also demonstrated. / text

Chemical flooding has been studied for 50 years. However, never have the conditions encouraging its growth been as good as right now. Those conditions being new, improved technology and oil prices high enough to make implementation economical. The objective of this work was to develop economical, robust chemical formulations and processes that recover oil in field pilots when properly implemented. This experimental study goes through the process of testing surfactants to achieve optimal phase behavior, coreflooding with the best chemical formulations, improving the formulation and testing it in more corefloods, and then finally recommending the formulation to be tested in a field pilot. The target reservoir contains a light (34° API, 10 cP), non-reactive oil at about 22° C. The formation is a moderate permeability (50 - 300 mD) sandstone with a high clay content (up to 13%). Different surfactants and surfactant mixtures were tested with the oil including alkyl benzene sulfonates (ABS), Guerbet alcohol sulfates (GAS), alkyl propoxy sulfates, and internal olefin sulfonates (IOS). The best formulation contained 0.75% TDA -13PO-SO₄, 0.25% C₂₀₋₂₄ IOS, 0.75% isobutanol (IBA), 1% Na₂CO₃, all which are mixed in a softened fresh water from a supply well. Corefloods recovered 93% of residual oil from reservoir cores. Core flood experiments were also done with the alkali sodium carbonate to measure the effluent pH in a Bentheimer sandstone core with a cation exchange capacity (CEC) of 2 meq/100g. Floods at frontal velocities of 100, 10, and 0.33 ft/D were performed with 0.3 pore volume slugs of 0.7% Na₂CO₃ at 86° C. The effluent was analyzed for ions and pH breakthrough. It was found that the pH breakthrough occurred before surfactant breakthrough would be expected as desired although the pH was lower at a frontal velocity of 0.33 ft/D than at the higher velocities. The Na₂CO₃ consumption was 0.244, 0.238, and 0.207 meq/100 g rock at velocities of 100, 10, and 0.33 ft/D, respectively. In addition, a no-alkaline formulation consisting of a new large hydrophobe ether carboxylate surfactant mixed with an internal olefin sulfonate was tested on an active oil and it successfully recovered 99% of the waterflood remaining oil from an Ottawa sand pack with no salinity gradient and no alkali. The final residual oil saturation after the chemical flood (S[subscript orc]) was only 0.005 / text