In Alabama, the term "coastal shoreline" applies to the Gulf shoreline and the shorelines of estuaries, bays, and sounds connected to the Gulf of Mexico and subject to its tides. However, Alabama shoreline studies have yet to include Little Lagoon, which has been connected to the Gulf of Mexico for most of the last 200 years, according to historical charts. This study used historical nautical charts, aerial photographs, and LIDAR derived shorelines from 1917 to 2004 to analyze shoreline change on Little Lagoon and its adjacent Gulf shoreline. The high water line was used as the common reference feature, and all shorelines were georeferenced, projected, and digitized in a Geographic In-formation System. Between 1917 and 2001, the Gulf shoreline eroded an average of 40 m over 12.7 km, with some transects eroding almost 120 m while others accreted almost 60 m. The greatest changes to the Gulf shoreline were found near natural inlets, downdrift of jetties, and coincident with nourishment projects. Between 1955 and 1997, Little Lagoon shrank 0.5%, or 51.4 km², from 10,285.9 km² to 10,234.5 km². The greatest changes to Little Lagoon were found on its southern shoreline and near inlets, human development, and hurricane overwash fans. A correlation analysis conducted on the Gulf shoreline and Little Lagoon' s southern shoreline indicated that although weak overall correlation values exist when the entire 12.7 km study area is compared, strong correlation values are obtained in some areas when compared over one kilometer sections. The strongest correlations were found in the same locations as the greatest changes. / Master of Science

O presente trabalho tem como objetivo compreender os processos que conduzem a estabilidade e a evolução morfológica do canal do rio Itaguaré em Bertioga - SP em uma escala de tempo histórica. Para isso, foram realizados os seguintes itens: a caracterização do clima de ondas, caracterização sedimentar, interpretação de fotografias aéreas, mapeamento das feições e delimitação das áreas de perigo relacionada à existência do canal. A análise da caracterização do clima de ondas foi realizada no software CAROL com uma série temporal de 1948 a 2010. As amostras de sedimentos foram coletas e processadas em laboratório por peneiramento e analisadas estatisticamente no software LBSE. A evolução histórica da desembocadura envolveu a escolha de fotografias aéreas de diferentes datas, as quais foram georreferenciadas e extraídas as linhas de costa, feições geomorfológicas e parâmetros específicos para a determinação da área de perigo relacionada ao canal. A caracterização da Barra de Itaguaré indica que a praia é composta por areias fina e muito fina, com ondas de maior incidência de SSE, SE e S. Para a análise da variação da linha de costa adjacente ao canal foi visto que no setor 1 teve progradação máxima de aproximadamente 80m e o setor 2 uma retração máxima de 53m. O canal foi classificado como de baixa energia de migração possuindo uma área de perigo estimada em 1.830m. A desembocadura de Itaguaré durante o período observado é estável quanto à posição na linha de costa e instável geometricamente quanto a sua morfologia, durante o período observado. / The present study has the objective to understand the morphological evolution processes that lead the inlet of Itaguaré, in Bertioga - SP, to stability. Thus, we conducted the following items: a characterization of the wave climate, sediment characterization, aerial photo interpretation, mapping features and delimitation the related inlets hazards areas. The analysis of the wave climate characterization was done in software CAROL with a time series from 1948 to 2010. Sediments samples were collected in field and processed in a laboratory by sieving. These samples were statistically analyzed with the software LBSE. For the inlet historical evolution used aerial photographs of different dates, which were georeferenced and used to extract coastlines, geomorphologic features, and specific parameters for determining inlets hazardous areas. The main results obtained for Itaguaré\'s Bar characterization was that the beach is composed of fine and very fine sand, with waves with a higher incidence of SSE, SE and S. Analysis of coastline variability adjacent to the inlet showed that the sector 1 had maximum progradation of nearly 80m and the sector 2 had a maximum retraction of 53m.The inlet was classified as low-energy migration and has a hazard area of 1830m. It was observed that the Itaguaré inlet is stable with respect to the position at the coastline and geometrically unstable with respect to its morphology.

O presente trabalho tem como objetivo compreender os processos que conduzem a estabilidade e a evolução morfológica do canal do rio Itaguaré em Bertioga - SP em uma escala de tempo histórica. Para isso, foram realizados os seguintes itens: a caracterização do clima de ondas, caracterização sedimentar, interpretação de fotografias aéreas, mapeamento das feições e delimitação das áreas de perigo relacionada à existência do canal. A análise da caracterização do clima de ondas foi realizada no software CAROL com uma série temporal de 1948 a 2010. As amostras de sedimentos foram coletas e processadas em laboratório por peneiramento e analisadas estatisticamente no software LBSE. A evolução histórica da desembocadura envolveu a escolha de fotografias aéreas de diferentes datas, as quais foram georreferenciadas e extraídas as linhas de costa, feições geomorfológicas e parâmetros específicos para a determinação da área de perigo relacionada ao canal. A caracterização da Barra de Itaguaré indica que a praia é composta por areias fina e muito fina, com ondas de maior incidência de SSE, SE e S. Para a análise da variação da linha de costa adjacente ao canal foi visto que no setor 1 teve progradação máxima de aproximadamente 80m e o setor 2 uma retração máxima de 53m. O canal foi classificado como de baixa energia de migração possuindo uma área de perigo estimada em 1.830m. A desembocadura de Itaguaré durante o período observado é estável quanto à posição na linha de costa e instável geometricamente quanto a sua morfologia, durante o período observado. / The present study has the objective to understand the morphological evolution processes that lead the inlet of Itaguaré, in Bertioga - SP, to stability. Thus, we conducted the following items: a characterization of the wave climate, sediment characterization, aerial photo interpretation, mapping features and delimitation the related inlets hazards areas. The analysis of the wave climate characterization was done in software CAROL with a time series from 1948 to 2010. Sediments samples were collected in field and processed in a laboratory by sieving. These samples were statistically analyzed with the software LBSE. For the inlet historical evolution used aerial photographs of different dates, which were georeferenced and used to extract coastlines, geomorphologic features, and specific parameters for determining inlets hazardous areas. The main results obtained for Itaguaré\'s Bar characterization was that the beach is composed of fine and very fine sand, with waves with a higher incidence of SSE, SE and S. Analysis of coastline variability adjacent to the inlet showed that the sector 1 had maximum progradation of nearly 80m and the sector 2 had a maximum retraction of 53m.The inlet was classified as low-energy migration and has a hazard area of 1830m. It was observed that the Itaguaré inlet is stable with respect to the position at the coastline and geometrically unstable with respect to its morphology.

I assessed the composition of zooplankton communities at the three tidal inlets connecting Lake Pontchartrain to Lake Borgne and subsequently to the Gulf of Mexico. The objectives of my research were to better understand the factors contributing to both spatial and temporal differences in zooplankton communities at the three locations. Monthly samplings of the neuston were conducted from September 2009 until April 2011 and then again from September 2012 until May 2013. Sampling consisted of triplicate tows using SeaGear “Bongo” nets. Water quality data along with water turbidity were recorded at each site and during each sampling effort. All specimens collected during the survey were quantified and identified to the lowest taxonomical unit. The results indicated that there were significant differences among the aquatic invertebrate communities composition among the three sites groups averaged across months (ANOSIM, R= 0.162, p = 0.001). The outcomes from this study could have strong implications for fisheries management and will provide a baseline for future research.

Blind Pass, a heavily structured wave-dominated tidal inlet on the west central coast of Florida, has undergone substantial morphologic changes in the past 150 years. Initially Blind Pass was a mixed-energy inlet. In 1848 a hurricane opened a new inlet to the north called Johns Pass, which captured a large portion of the tidal prism of Blind Pass. Since then Blind Pass migrated southward until it was structurally stabilized in 1937. The decreasing tidal prism resulted in significant inlet channel filling. The channel has been dredged 12 times since 1937. The present inlet is stabilized by two jetties and a series of seawalls. Detailed time-series field measurements of bathymetry and tidal flows were conducted between 2001 and 2004, after the last channel dredging in the summer of 2000. The measured depositional rate in the inlet channel approximately equals the net southward longshore transport rate. This suggests that the inlet has served as a trap for the southward longshore transport allowing negligible bypassing to the eroding downdrift beach. Most of the active sedimentation occurs on the northern side of the inlet. The sediment in the thalweg is largely coarse shell lag, indicating adequate sediment flushing by the ebbing tide. The cross-channel flow measurements revealed that ebb flow was approximately twice as high in the channel thalweg as compared with the rest of the channel. The flood flow was largely uniform across the entire inlet and dominated over the northern portion of the inlet due to the weak ebb flow there. This cross-channel flow pattern is crucial to the understanding of the sedimentation patterns in the Blind Pass channel. Two years after the last dredging the mouth has become shallow enough to induce wave breaking across the shoal area. Distinctive seasonal patterns of sedimentation were measured thereafter in the inlet channel, influenced by seasonal wave climate. The sedimentation is event driven from passage of cold fronts bringing elevated wave energy that accelerates the southward longshore transport. During normal conditions the sediment deposited in the mouth area is redistributed further into the inlet by the flood current combined with wave-driven current.

A circumferential slot In-line Virtual Impactor (IVI) has been designed using Computational Fluid Dynamics (CFD) simulation tools and experimentally characterized using monodispersed liquid aerosols to validate simulation results. The base design, IVI-100, has an application as a pre-separator for sampling inlets, where the device scalps large particles from the aerosol size distribution. The IVI-100 samples air in at 111 L/min and deliver the fine aerosol fraction in a 100 L/min flow and provide a cutpoint particle size of 10 µm, with a pressure drop of 45 Pa. An inverted dual cone configuration encased inside a tube provides the IVI-100 with a characteristic circumferential slot of width 0.254 mm (0.100 inches) and a slot length of 239 mm (9.42 inches) at the critical zone. The upper cone causes the flow to accelerate to an average throat velocity of 3.15 m/s, while the lower cone directs the major flow toward the exit port and minimizes recirculation zones that could cause flow instabilities in the major flow region. The cutpoint Stokes number is 0.73; however, the cutpoint can be adjusted by changing the geometrical spacing between the acceleration nozzle exit plane and a flow divider. Good agreement is obtained between numerically predicted and experimentally observed performance. An aerosol size selective inlet for bioaerosol and other air sampling applications using an upgraded prototype of IVI-100, mounted inside a BSI-100 inlet shell was tested in an aerosol wind tunnel over a speed range of 2 – 24 km/hr. The BSI-IVI-100 inlet has a cutpoint of 11 µm aerodynamic diameter and delivers the fine fraction at 100 L/m. The geometric standard deviation of the fractionation curve is 1.51 and the performance is not affected by wind speeds. An IVI-350, which is an adaptation of the IVI to be used as a powder fractionator, was designed based on computational simulations, and provides a cutpoint of 3 µm AD, while operating in a total flow rate of 350 L/min. Four Identical IVI -350 units will be operated in parallel to fractionate aerosolized powders in a 1400 L/min flow. An optimized inlet, with a contoured tear-drop shaped insert provides uniform flow to four identical IVI units and prevents powder accumulation in the system entrance.

Thesis (Ph.D.) -- University of Rhode Island, 2008. / Typescript. Includes bibliographical references (leaves 132-141).

Thesis (Ph.D.) -- University of Rhode Island, 2008. / Title from PDF title page (viewed on May 21, 2010) Available through UMI ProQuest Digital Dissertations. Includes bibliographical references (leaves 132-141). Also issued in print.

Thesis (M.S.)--University of North Carolina at Wilmington, 2006. / Includes bibliographical references (leaves: 95-98)

This work tests the validity of using a commercial cloud condensation nuclei (CCN) counter (CCNc) on the Facility for Airborne Atmospheric Measurements (FAAM) research aircraft. The CCNc was suitable for aircraft work with sta- ble and repeatable supersaturation, temperature and pressure relationships. The sample architecture of the aircraft fitted CCNc was found to transmit particles with acceptable losses in the diameter range of interest as was a pressure control device designed for airborne work. Rosemount inlets, used to sample aerosol, were found to be sensitive to particle density resulting in disparate aerosol being sam- pled with different efficiencies. In dust dominated aerosol inlet efficiency peaks at 10.24 at an optical diameter of 2.91 μm, with a minimum inlet efficiency between 1.78 and 1.51 at 0.28μm. In less dense aerosol inlets sample representatively below 0.6 μm and comparably below 1.0 μm. The thorough testing of the CCNc, associated sampling architecture and mea- surement strategies, enabled vertical and horizontal CCN to be investigated along with other aerosol and cloud microphysical properties in the Southern Equato- rial Pacific (SEP). The primary source of particulates was the South American continent, with sulphate dominating composition. There were strong gradients in aerosol and gas phase chemistry concentration with distance from the coast and in the cloud microphysics measurements where highest droplet numbers and smallest diameters were close to the coast. These data represent an important validatory and parameterisation data set for models of all scales. CCN data were used to calculate the aerosol hygroscopicity parameter, the mean project value, κ, was 0.21 ± 0.18 . There was no evident variation in hygroscopicity with distance from the Chilean coastline suggesting a single dominant source and a well mixed boundary layer up to 907km to the west. CCN measurements were also com- pared to predictions from multiple models of different composition and mixing state assumptions. The best CCN closure used an external mixture of inorganic and organic aerosol components, with a modelled to observed ratio of 1.37 ± 0.32. It was hypothesised that this large ratio and the relatively low bulk hy- groscopicity was influenced by an external mixture. Incorporating this external mixture is imperative if CCN are to be accurately modelled and any subsequent cloud processes accurately captured.