Thesis (M.S.)--Florida State University, 2004. / Advisor: Dr. James O'Brien, Florida State University, College of Arts and Sciences, Dept. of Meteorology. Title and description from dissertation home page (viewed Jan. 13, 2005). Includes bibliographical references.

Thesis (M.S.)--Florida State University, 2004. / Advisor: Dr. Paul Ruscher, Florida State University, College of Arts and Sciences, Dept. of Meteorology. Title and description from dissertation home page (viewed Jan 18, 2005). Includes bibliographical references.

Thesis (M.S.)--University of North Carolina at Wilmington, 2004. / Includes bibliographical references (leaves : 60-61).

Tropical Storm Irene’s most extreme rainfall resulted in record-breaking sediment loads from upland tributaries to the Connecticut River. However, was the event exceptional with respect to resultant deposition downstream? Off-river waterbodies to the Lower Connecticut River, such as cut-off meanders and blocked valley lakes, are a particularly important floodplain environment, which have been shown to serve as a focal point for the trapping of sediment and associated contaminants. This study evaluates the relative role of extreme events like Tropical Storm Irene in infilling these off-river environments. To meet this objective we compare the magnitude and composition of resultant sedimentation from Irene to that observed following the 2011 and 2013 spring freshets. Tropical Storm Irene deposits were identified as compositionally distinct, grey layers that were relatively inorganic compared to sediments deposited by the annual spring freshet. Sediment within the Irene deposit was enriched in elemental potassium and depleted in zircon, a finding consistent with being enriched by glacigenic lacustrine and till sediments. Decreased mercury levels in the Irene deposits suggest that this event served to cap highly contaminated, industrial era sediment with a layer of relatively clean, fine-grained silt and clay. Resampling of these waterbodies in Fall 2012 revealed preservation of the 2-3 cm thick Irene deposit as well as 3-4 cm of more recent sediments deposited on top of this event. Sediment contributions from rare events, like Tropical Storm Irene, were found to be less influential than the annual spring freshet in the long-term infilling of waterbodies along the Lower Connecticut River. However, sediments from Irene are compositionally unique and serve to highlight the importance of this event in removing glacially derived fines from the river’s upland catchments.

A two-dimensional numerical model (RiverFLO-2D) has been enhanced to simulate flooding of urban areas by developing an innovative wet and dry surface algorithm, accounting for variable rainfall, and recoding the model computer program for parallel computing. The model formulation is based on the shallow water equations solved with an explicit time-stepping element-by-element finite element method. The dry-wet surface algorithm is based on a local approximation of the continuity and momentum equations for elements that are completely dry. This algorithm achieves global volume conservation in the finite element, even for flows over complex topographic surfaces. A new module was implemented to account for variable rainfall in space and time using NEXRAD precipitation estimates. The resulting computer code was parallelized using OpenMP Application Program Interface, which allows the model to run up to 5 times faster on multiple core computers. The model was verified with analytical solutions and validated with laboratory and field data. Model application to the Malpasset dam break and Sumacarcel flooding event show that the model accurately predicts flood wave travel times and water depths for these numerically demanding real cases. To illustrate the predictive capability of the enhanced model, an application was made of the city of Sweetwater flooding in Miami-Dade County, FL caused by the Hurricane Irene. The simulation starts with dry bed and rainfall is provided by NEXRAD estimates. Integrating NEXRAD rainfall estimates, developing a novel dry-wet area algorithm and parallelizing RiverFLO-2D code, this dissertation presents a proof of concept to accurately and efficiently predict floods in urban areas, identifying future improvements along this line of research.

The phenomenon of climate change exists in a liminal state between denial and acceptance, past and future, theory and reality, problem and catastrophe, unfolding in the spaces between apparently stable forms. This thesis considers different temporalities emerging within this transition through a creative exploration of extreme weather and climatic events that seeks to foreground the idea of change itself. Research centers around the Florida Keys, a low lying archipelago that is widely expected to become uninhabitable in the next half century due to sea level rise, but only if the islands do not suffer a similar fate much sooner with the sudden arrival of a catastrophic hurricane. While most Keys residents are unconcerned about the growing reality of sea level rise, hurricanes are a constant threat generating a palpable atmosphere of anticipation and corresponding precaution. In resonance with this regular storm activity in the Florida Keys, the project also reflects on the coincidental occurrence of Hurricanes Irene (2011) and Sandy (2012), two errant and devastating storms that visited the northeastern United States over the course of this project and personally affected the author. Thus, extreme weather provides a material entry point into the complex and far-reaching event of climate change, offering an opportunity to theorize transition and to reflect on what might be creatively recuperated from cross currents of climate and catastrophe. In conclusion, the thesis proposes an ontology inspired by the unique reproductive strategy of the mangrove plant that has thickly and extensively colonized the coastline of southern Florida and through which events are understood to possess qualities of latency, accrual and distribution and to give rise to a future that is germinal, a present that is continuously resignified and a past that remains profoundly creative.