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Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

2016

Electronic Theses and Dissertations

Oceanography and Atmospheric Sciences and Meteorology

Articles 1 - 8 of 8

Full-Text Articles in Physical Sciences and Mathematics

An Ensemble Study Of The Sea Level Rise Impact On Storm Surge And Inundation In The Coastal Bangladesh, Mansur Ali Jisan Dec 2016

An Ensemble Study Of The Sea Level Rise Impact On Storm Surge And Inundation In The Coastal Bangladesh, Mansur Ali Jisan

Electronic Theses and Dissertations

The hydrodynamic model Delft3D is used to study the impact of Sea Level Rise (SLR) on storm surge and inundation in the coastal region of Bangladesh. To study the present-day inundation scenario, track of two known tropical cyclones (TC) were used: Aila (Category 1; 2009) and Sidr (Category 5; 2007). Model results were validated with the available observations. Future inundation scenarios were generated by using the strength of TC Sidr, TC Aila and an ensemble of historical TC tracks but incorporating the effect of SLR. Since future change in storm surge inundation under SLR impact is a probabilistic incident, that’s …

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Roles Of Siphon Flows In Suspension Feeding, Kevin Du Clos Dec 2016

Roles Of Siphon Flows In Suspension Feeding, Kevin Du Clos

Electronic Theses and Dissertations

Benthic marine suspension feeders provide an important link between benthic and pelagic ecosystems. The strength of this link is determined by suspension-feeding rates. Many studies have measured suspension-feeding rates using indirect clearance-rate methods, which are based on the depletion of suspended particles. Direct methods that measure the flow of water itself are less common, but they can be more broadly applied because clearance-rate measurements are affected by properties of the cleared particles. We present pumping rates for three species of suspension feeders, the clams Mya arenaria and Mercenaria mercenaria and the tunicate Ciona intestinalis, calculated using a direct method …

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A Comparison Of Global Climate Reanalysis And Climate Of South Greenland And The North Atlantic, Jeff Auger Dec 2016

A Comparison Of Global Climate Reanalysis And Climate Of South Greenland And The North Atlantic, Jeff Auger

Electronic Theses and Dissertations

Global climate reanalysis models are regularly used in many scientific fields concerning climate and atmospheric observation. This thesis utilizes reanalysis models in two chapters in order to gain insight into North Atlantic climate teleconnections and their relation to precipitation across South Greenland. This first chapter of this thesis compares the four most recent reanalysis models – ECMWF Reanalysis Interim (ERA-I), NCEP Climate Forecast System Reanalysis (CFSR), JMA 55-year Reanalysis (JRA-55), and NASA Modern-Era Retrospective Analysis for Research and Applications (MERRA) – and develops from these models a monthly-mean ensemble average of common meteorological variables for the period 1979-2013. Results from …

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Declining Dissolved Oxygen In The Central California Current Region, Alice Ren Dec 2016

Declining Dissolved Oxygen In The Central California Current Region, Alice Ren

Electronic Theses and Dissertations

A potential consequence of climate change is a global decrease in dissolved oxygen at depth due to changes in the balance of ventilation, mixing, respiration, and photosynthesis in the oceans. Regionally, the California Current has experienced dissolved oxygen declines since the late 1980s with observations from Oregon and the Southern California Bight. Here, we present observations of declining dissolved oxygen along CalCOFI Line 67 off of Monterey Bay, in the Central California Current region, and investigate likely mechanisms. The hydrographic cruises obtained dissolved oxygen measurements 50-300 km from shore between 1998 and 2013, with quasi-seasonal sampling resolution. Dissolved oxygen decreased …

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Sediment Accumulations Patterns In The Damariscotta River Estuary, Emily A. Chandler Aug 2016

Sediment Accumulations Patterns In The Damariscotta River Estuary, Emily A. Chandler

Electronic Theses and Dissertations

The tidally dominated Damariscotta River estuary is located on the south-central Maine coast. The elongate, north-south orientation of the estuary is characteristic of the indented shoreline in this region and a consequence of the bedrock structural framework, comprised of Paleozoic high-grade metasedimentary rocks. Pegmatite sills form bedrock constriction points that divide the estuary into seven distinct basins. The narrow, bending geometry and sill and basin morphology impact the distribution of sediment within the estuary and the hydrodynamics of the system. This study employs multibeam bathymetry surveys, sediment grab samples and radionuclide analysis (210Pb and 137Cs) of sediment …

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Size As A Trait For Understanding The Role Of Zooplankton In The Biological Carbon Pump, Karen Stamieszkin Aug 2016

Size As A Trait For Understanding The Role Of Zooplankton In The Biological Carbon Pump, Karen Stamieszkin

Electronic Theses and Dissertations

Living organisms impact carbon transport between the atmosphere and the ocean through the biological carbon pump. Some plankton communities augment carbon export from the ocean’s surface, and are thought to have a major role in global climate. These export communities are often characterized by larger organisms that sink to depths where the carbon they contain is sequestered from the atmosphere. Zooplankton can enhance export by aggregating prey into larger sinking fecal pellets; however fecal pellet flux is a highly variable component of the biological carbon pump. Relating plankton trophic dynamics to changes in particulate carbon flux is an important step …

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Tornado Density And Return Periods In The Southeastern United States: Communicating Risk And Vulnerability At The Regional And State Levels, Michelle Bradburn Aug 2016

Tornado Density And Return Periods In The Southeastern United States: Communicating Risk And Vulnerability At The Regional And State Levels, Michelle Bradburn

Electronic Theses and Dissertations

Tornado intensity and impacts vary drastically across space, thus spatial and statistical analyses were used to identify patterns of tornado severity in the Southeastern United States and to assess the vulnerability and estimated recurrence of tornadic activity. Records from the Storm Prediction Center's tornado database (1950-2014) were used to estimate kernel density to identify areas of high and low tornado frequency at both the regional- and state-scales. Return periods (2-year, 5-year, 10-year, 25-year, 50-year, and 100-year) were calculated at both scales as well using a composite score that included EF-scale magnitude, injury counts, and fatality counts. Results showed that the …

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Source Apportionment Of Atmospheric Particulate Matter In Developing Countries Using Trace Elements And Stable Metal Isotope Ratios, Nitika Dewan Jan 2016

Source Apportionment Of Atmospheric Particulate Matter In Developing Countries Using Trace Elements And Stable Metal Isotope Ratios, Nitika Dewan

Electronic Theses and Dissertations

The work presented herein details the source apportionment of atmospheric particulate matter in developing countries (Kyrgyzstan in Central Asia, metropolitan cities in Northern India, and Shenzhen in China) using trace elements and stable metal isotope ratios. The first study focused on the development of a novel method for the concomitant separation of rare-earth elements in environmental samples of any geological origin. The separation procedure is based on three extraction chromatographic materials, referred to as Sr.Spec, TRU.Spec, and Ln.Spec. This triple column arrangement enables the simultaneous isolation of pure Sr and Nd fractions in less than one day and with great …

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