Matagorda Peninsula is located along an interfluvial region of the central Texas coast in the northwestern Gulf of Mexico. The Pleistocene Beaumont Clay underlies the coastal plain and inner continental shelf and controls the general slope of the coast in this region. This clay surface also creates low accommodation space for the preservation of modern sediments. As a result, only a thin (1 m) layer of transgressive Holocene muddy sand extends throughout the lower shoreface. On 15 July, 2003, Hurricane Claudette (Category 1) made landfall on the peninsula. Following the storm, the shoreface was found to be an extensively eroded surface. Most obvious on this surface was an area containing numerous scour pits on the lower shoreface. These pits extended through the Holocene sediment and into the underlying Beaumont Clay. By the following July, the shoreface exhibited a relatively flat and featureless appearance. Rapid infilling of the pits was attributed to the high sediment supply to the area from converging longshore currents and by the relatively high accommodation space offered by the scoured areas. A large amount of sediment was removed from the lower shoreface where the formation of scour pits occurred. This sediment would have been available for depositionin storm layers both inshore and offshore of the scoured area. Within scour pits, accommodation space was high, resulting in sediment deposition and rapid infilling of the pits. Outside of the scour pits, accommodation space remained low and sediment deposition did not occur. Preservation potential of the sediment record on the shoreface was low and was controlled by cycles of erosion and deposition during storm events. Antecedent geology of the shoreface and the sedimentary processes occurring during and after the storm supported arguments against the assumptions used by the classic "profile of equilibrium" model. Finally, the heavily scoured surface represents a geohazard to development of nearshore regions.

In my thesis, I examine the racial history of New Orleans, Louisiana, through the lens of Mardi Gras. After the introduction, I begin with the history of the celebration and its European origin, in chapter two. Then, I move onto the discovery of New Orleans. In chapter three I look at the 1811 slave rebellion in New Orleans, which was the largest in United States' history. In chapter four I explore race and Mardi Gras in the nineteenth century, and the same in chapter five, but in the twentieth century. In chapter six I look at the twenty-first century in New Orleans, and Hurricane Katrina, in particular. In sum, I argue that the practice of Mardi Gras and the existence of racial conflict both separate and unite the New Orleanian community, producing the attitude and identity of the “New Orleanian.”

First responders who participate in disaster are at risk of posttraumatic stress disorder (PTSD). Because of nurses’ unique role as professional and volunteer responders, there is a need to know more about risks of PTSD in this group. Using a cross-sectional correlational design, associations between disaster exposure, problem focused coping (PFC), emotion-focused coping (EFC) and PTSD symptoms (Impact of Events Scale-Revised (IES-R) scale) were explored. A random sample (n= 995) was drawn from a list of nurses from the New Orleans region. Each nurse was mailed an invitation to participate in an online survey. Three post-card reminders were sent. The sample was divided into nurses who participated in disaster activities (n=76) and those who did not (n=32). Prevalence of PTSD in the PIDA nurses was 13.2%. Almost half the PIDA nurses (48.7%) reported symptoms of PTSD, and increased use of substances to cope (31.5%). Only 9.2% sought psychological care post-event. Regression analyses, controlling for history of trauma, marital status, and gender found EFC accounted for a significant amount of the variance of symptoms of PTSD (R2 = 0.32, F (1, 67) = 25.09, p < 0.001) (B=0.4, SE=0.01, p Prevalence of PTSD among PIDA nurses was lower than other groups of professional responders (17.4% in firefighters), but greater than the general public (6.8%). Presence of PTSD in PIDA nurses five years after Hurricane Katrina is associated with the increased use of EFC and substances.

Given the past history and future risk of storm surge in the United States, alternative storm protection techniques are needed to protect vital sectors of the economy and population, particularly within southeastern Louisiana. It is widely hypothesized that coastal wetlands offer protection from storm surge and wave action, though the extent of this protection is unknown due to the complex physics behind vegetated flow dynamics. This thesis presents numerical modeling results that estimate the relative sensitivity of waves and storm surge to characteristics embodied by coastal wetlands. An idealized grid domain and 400 km2 (20 km by 20 km) marsh feature provide a controlled environment for evaluating marsh characteristics, including bottom friction, elevation, and continuity. Marsh continuity is defined as the ratio of healthy marsh area to open water area within the total wetland area. It is determined that increased bottom friction reduces storm surge levels and wave heights. Through the roughening of the bottom from sandy to covered with tall grass, it is estimated that waves may be dampened by up to 1.2 m at the coast, and peak surge may be reduced by as much as 35%. The lowering of marsh elevation generally increases wave heights and decreases surge levels, as expected. A 3.5 m decrease in marsh elevation results in as much as a 2.6 m increase in wave height, and up to a 15% decrease in surge levels. Reductions in marsh continuity enhance surge conveyance into and out of the marsh. For storms of low surge potential, surge is increased by as much as 70% at the coast due to decreasing marsh continuity from 100% to 50%, while for storms of high surge potential, surge is decreased by 5%. This indicates that for storms of high surge potential, a segmented marsh may offer comparable surge protection to that of a continuous marsh. Wave heights are generally increased within the marsh due to the transmission of wave energy through marsh channels. Results presented in this thesis may assist in the justification of coastal wetland mitigation, and optimize marsh restoration in terms of providing maximum storm protection.

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.

The Texas-Louisiana Shelf Circulation and Transport Study featured moorings that covered the shelf during 1992 to 1994, and captured the oceanic response on the shelf to category 4 Hurricane Andrew in August of 1992. Eighty-one current meters distributed over 31 moorings along several contours of isobaths provided excellent spatial and temporal coverage over the shelf. The low-frequency variability (2 days and longer) of current observations and tide gauges to the West of the storm are analyzed after the passage of Andrew, focusing on the region outside of direct hurricane forcing. Wavelet analyses are utilized to investigate the dominant periods excited by the storm over the shelf and their temporal evolution after forcing has subsided. Subsequent to the storm's passage, the observations and wavelet transforms show a two-to-four day period coastal trapped wave that propagate westward at speeds near 6 m/s and then around the Texas bend along the bathymetry. The signal remains detectable in observations as far south as Port Isabel, Texas. The prominent frequencies determined from wavelet analysis are compared with predicted coastal trapped wave dispersion modes and show good agreement in the predicted group speed and cross-shelf structure of the first mode. The energies calculated from the data indicate a largely barotropic shelf wave response which is corroborated in the observed currents and by theory.

Recent hurricanes in the Gulf of Mexico (e.g., Ivan, Dennis, Katrina, Rita and Ike) were observed to develop wave conditions that were near or exceeded the predicted 100-year conditions. As a result, many offshore facilities, as well as coastal infrastructure, which were designed to withstand the 100-year condition, were damaged. New estimates of extreme conditions, which incorporate recently observed maxima, are needed to provide better guidelines for design of coastal and offshore structures. Berek et al. (2007) have used modeled data to develop new criteria, but these estimates can be very sensitive to the data and to the statistical methods used in the development. Berek's estimates also do not cover the entire Gulf of Mexico. We have developed updated estimates of the 100-year extreme wave conditions for the entire Gulf of Mexico using a more comprehensive approach. First, the applicability of standard parametric wind models was examined and appropriate adjustments to the Rankine vortex model were developed to reduce the wind field errors during hurricane conditions. The adjusted winds reduced the error by up to 25 percent compared to the original Rankine vortex model. To obtain reliable wave data, merged wind fields were generated using the NCEP/NCAR Reanalysis 1 project modeled wind data for background wind and the parametric wind model for hurricane conditions. Next, the SWAN wave model was used for the 51-year period from 1958 to 2008 along with multiple statistical methods (Gumbel, Weibull and GEV-Generalized Extreme Value distribution). The effect of the recent hurricane season (2004-2008) shows that maximum 100-year wave height values and their distribution changes. A resampling technique (bootstrap) is used to evaluate and select the optimum statistical method to estimate more appropriate extreme wave conditions.

Sedimentation rates in sediment cores from Lavaca Bay have been high within the last 1-2 decays within the central portion of the bay, with small fluctuations from river input. Lavaca Bay is a broad, flat, and shallow (<3 m) microtidal estuary within the upper Matagorda Bay system. Marine derived sediment enters the system from Matagorda Bay, while two major rivers (Lavaca & Navidad) supply the majority of terrestrially derived sediment. With continuous sediment supply the bay showed no bathymetric change until the introduction of the shipping channel. Processes that potentially lead to sediment transport and resuspension within the bay include wind driven wave resuspension, storm surges, wind driven blowouts, and river flooding. These processes were assessed using X-radiographs, grain size profiles, and 210Pb and 137Cs geochronology of sediment diver cores. In six cores the upper 10 cm of the seabed has been physically mixed, where as the rest showed a continuous sediment accumulation rate between 0.84-1.22 cm/yr. Sidescan sonar and subbottom chirp sonar data coupled with sedimentological core and grab samples were used to map the location and delineate the sedimentary facies within the estuarine system in depths >1 m. Five sedimentary facies were identified in Lavaca Bay and adjacent bays, they are: 1) estuarine mud; 2) fluvial sand; 3) beach sand; 4) bay mouth sand; and 5) oyster biofacies. Of the five facies, Lavaca Bay consists primarily of estuarine mud (68%). Pre-Hurricane and post-Hurricane Claudette cores were obtained to observe the impact to the sedimentary processes. The north and south Lavaca Bay were eroded by 10 cm and 2-3 cm, respectively. Cox Bay and Keller Bay saw a net deposition of 2-3 cm.

Matagorda Peninsula is located along an interfluvial region of the central Texas coast in the northwestern Gulf of Mexico. The Pleistocene Beaumont Clay underlies the coastal plain and inner continental shelf and controls the general slope of the coast in this region. This clay surface also creates low accommodation space for the preservation of modern sediments. As a result, only a thin (1 m) layer of transgressive Holocene muddy sand extends throughout the lower shoreface. On 15 July, 2003, Hurricane Claudette (Category 1) made landfall on the peninsula. Following the storm, the shoreface was found to be an extensively eroded surface. Most obvious on this surface was an area containing numerous scour pits on the lower shoreface. These pits extended through the Holocene sediment and into the underlying Beaumont Clay. By the following July, the shoreface exhibited a relatively flat and featureless appearance. Rapid infilling of the pits was attributed to the high sediment supply to the area from converging longshore currents and by the relatively high accommodation space offered by the scoured areas. A large amount of sediment was removed from the lower shoreface where the formation of scour pits occurred. This sediment would have been available for depositionin storm layers both inshore and offshore of the scoured area. Within scour pits, accommodation space was high, resulting in sediment deposition and rapid infilling of the pits. Outside of the scour pits, accommodation space remained low and sediment deposition did not occur. Preservation potential of the sediment record on the shoreface was low and was controlled by cycles of erosion and deposition during storm events. Antecedent geology of the shoreface and the sedimentary processes occurring during and after the storm supported arguments against the assumptions used by the classic "profile of equilibrium" model. Finally, the heavily scoured surface represents a geohazard to development of nearshore regions.

Thesis (M. P. A.)--Texas State University-San Marcos, 2009. / "Fall 2009." Includes bibliographical references (leaves 104-109).