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Full-Text Articles in Engineering
Evaluation Of Fresh Groundwater Resources And Nitrogen Discharge To The Coastal Lagoon Of An Atoll Island, James D. Gale
Evaluation Of Fresh Groundwater Resources And Nitrogen Discharge To The Coastal Lagoon Of An Atoll Island, James D. Gale
Electronic Thesis and Dissertation Repository
Atoll island communities face socio-economic challenges together with environmental pressures imposed by climate change that are causing increased water quality degradation. Wastewater from domestic septic systems is released into the subsurface on Fongafale Islet, Tuvalu. It is unclear if this is contributing to high nitrogen (N) concentrations and eutrophication of the adjacent coastal lagoon. In this study, a variable-density groundwater flow and conservative contaminant transport model was developed in SEAWAT-2005 to simulate the salinity distribution and N transport through the Fongafale Islet aquifer. Model simulations evaluated the influence of tides, variable (interannual) recharge patterns, wastewater loading rates and wastewater source …
The Influence Of Channel Deepening On Tides, River Discharge Effects, And Storm Surge, Stefan A. Talke, Ramin Familkhalili, David A. Jay
The Influence Of Channel Deepening On Tides, River Discharge Effects, And Storm Surge, Stefan A. Talke, Ramin Familkhalili, David A. Jay
Civil and Environmental Engineering Faculty Publications and Presentations
We combine archival research, semi-analytical models, and numerical simulations to address the following question: how do changes to channel geometry alter tidal properties and flood dynamics in a hyposynchronous, strongly frictional estuary with a landward decay in tidal amplitudes? Records in the Saint Johns River Estuary since the 1890s show that tidal range has doubled in Jacksonville, Florida. Near the estuary inlet, tidal discharge approximately doubled but tidal amplitudes increased only ~6%. Modeling shows that increased shipping channel depths from 5-6 to ~13m drove the observed changes, with other factors like channel shortening and width reduction producing comparatively minor effects. …
The Influence Of Channel Deepening On Tides, River Discharge Effects, And Storm Surge, S. A. Talke, Ramin Familkhalili, D. A. Jay
The Influence Of Channel Deepening On Tides, River Discharge Effects, And Storm Surge, S. A. Talke, Ramin Familkhalili, D. A. Jay
Civil & Environmental Engineering Faculty Publications
We combine archival research, semi-analytical models, and numerical simulations to address the following question: how do changes to channel geometry alter tidal properties and flood dynamics in a hyposynchronous, strongly frictional estuary with a landward decay in tidal amplitudes? Records in the Saint Johns River Estuary since the 1890s show that tidal range has doubled in Jacksonville, Florida. Near the estuary inlet, tidal discharge approximately doubled but tidal amplitudes increased only ∼6%. Modeling shows that increased shipping channel depths from ∼5 to ∼13m drove the observed changes, with other factors like channel shortening and width reduction producing comparatively minor effects. …
Coupling Of Sea Level And Tidal Range Changes, With Implications For Future Water Levels, Adam T. Devlin, David A. Jay, Stefan Talke, Edward D. Zaron, Jiayi Pan, Hui Lin
Coupling Of Sea Level And Tidal Range Changes, With Implications For Future Water Levels, Adam T. Devlin, David A. Jay, Stefan Talke, Edward D. Zaron, Jiayi Pan, Hui Lin
Civil and Environmental Engineering Faculty Publications and Presentations
Are perturbations to ocean tides correlated with changing sea-level and climate, and how will this affect high water levels? Here, we survey 152 tide gauges in the Pacific Ocean and South China Sea and statistically evaluate how the sum of the four largest tidal constituents, a proxy for the highest astronomical tide (HAT), changes over seasonal and interannual time scales. We find that the variability in HAT is significantly correlated with sea-level variability; approximately 35% of stations exhibit a greater than ±50 mm tidal change per meter sea-level fluctuation. Focusing on a subset of three stations with long records, probability …
Relative Sea-Level Trends In New York City During The Past 1500 Years, Andrew C. Kemp, Troy D. Hill, Christopher H. Vane, Niamh Cahill, Philip M. Orton, Stefan A. Talke, Andrew C. Parnell, Kelsey Sanborn, Ellen K. Hartig
Relative Sea-Level Trends In New York City During The Past 1500 Years, Andrew C. Kemp, Troy D. Hill, Christopher H. Vane, Niamh Cahill, Philip M. Orton, Stefan A. Talke, Andrew C. Parnell, Kelsey Sanborn, Ellen K. Hartig
Civil and Environmental Engineering Faculty Publications and Presentations
New York City (NYC) is threatened by 21st-century relative sea-level (RSL) rise because it will experience a trend that exceeds the global mean and has high concentrations of low-lying infrastructure and socioeconomic activity. To provide a long-term context for anticipated trends, we reconstructed RSL change during the past ~1500 years using a core of salt-marsh sediment from Pelham Bay in The Bronx. Foraminifera and bulk-sediment δ13C values were used as sea-level indicators. The history of sediment accumulation was established by radiocarbon dating and recognition of pollution and land-use trends of known age in down-core elemental, isotopic, and pollen …
A Validated Tropical-Extratropical Flood Hazard Assessment For New York Harbor, Philip M. Orton, T. M. Hall, Stefan A. Talke, Alan F. Blumberg, Nickitas Georgas, S. Vinogradov
A Validated Tropical-Extratropical Flood Hazard Assessment For New York Harbor, Philip M. Orton, T. M. Hall, Stefan A. Talke, Alan F. Blumberg, Nickitas Georgas, S. Vinogradov
Civil and Environmental Engineering Faculty Publications and Presentations
Recent studies of flood risk at New York Harbor (NYH) have shown disparate results for the 100 year storm tide, providing an uncertain foundation for the flood mitigation response after Hurricane Sandy. Here we present a flood hazard assessment that improves confidence in our understanding of the region's present-day potential for flooding, by separately including the contribution of tropical cyclones (TCs) and extratropical cyclones (ETCs), and validating our modeling study at multiple stages against historical observations. The TC assessment is based on a climatology of 606 synthetic storms developed from a statistical-stochastic model of North Atlantic TCs. The ETC assessment …
Recent Progress In Performance Evaluations And Near Real-Time Assessment Of Operational Ocean Products, Fabrice Hernandez, Edward Blockley, Gary B. Brassington, Fraser Davidson, Prasanth Divakaran, Marie Drévillon, Shiro Ishizaki, Marcos Garcia-Sotillo, Patrick J. Hogan, Priidik Lagemaa, Bruno Levier, Matthew Martin, Avichal Mehra, Christopher Mooers, Nicolas Ferry, Andrew Ryan, Charly Regnier, Alistair Sellar, Gregory C. Smith, Sarantis Sofianos, Todd Spindler, Gianluca Volpe, John Wilkin, Edward Zaron, Aijun Zhang
Recent Progress In Performance Evaluations And Near Real-Time Assessment Of Operational Ocean Products, Fabrice Hernandez, Edward Blockley, Gary B. Brassington, Fraser Davidson, Prasanth Divakaran, Marie Drévillon, Shiro Ishizaki, Marcos Garcia-Sotillo, Patrick J. Hogan, Priidik Lagemaa, Bruno Levier, Matthew Martin, Avichal Mehra, Christopher Mooers, Nicolas Ferry, Andrew Ryan, Charly Regnier, Alistair Sellar, Gregory C. Smith, Sarantis Sofianos, Todd Spindler, Gianluca Volpe, John Wilkin, Edward Zaron, Aijun Zhang
Civil and Environmental Engineering Faculty Publications and Presentations
Operational ocean forecast systems provide routine marine products to an ever-widening community of users and stakeholders. The majority of users need information about the quality and reliability of the products to exploit them fully. Hence, forecast centres have been developing improved methods for evaluating and communicating the quality of their products. Global Ocean Data Assimilation Experiment (GODAE) OceanView, along with the Copernicus European Marine Core Service and other national and international programmes, has facilitated the development of coordinated validation activities among these centres. New metrics, assessing a wider range of ocean parameters, have been defined and implemented in real-time. An …
Channel Shallowing As Mitigation Of Coastal Flooding, Philip M. Orton, Stefan A. Talke, David A. Jay, Larry Yin, Alan F. Blumberg, Nickitas Georgas, Haihong Zhao, Hugh J. Roberts, Kytt Macmanus
Channel Shallowing As Mitigation Of Coastal Flooding, Philip M. Orton, Stefan A. Talke, David A. Jay, Larry Yin, Alan F. Blumberg, Nickitas Georgas, Haihong Zhao, Hugh J. Roberts, Kytt Macmanus
Civil and Environmental Engineering Faculty Publications and Presentations
Here, we demonstrate that reductions in the depth of inlets or estuary channels can be used to reduce or prevent coastal flooding. A validated hydrodynamic model of Jamaica Bay, New York City (NYC), is used to test nature-based adaptation measures in ameliorating flooding for NYC’s two largest historical coastal flood events. In addition to control runs with modern bathymetry, three altered landscape scenarios are tested: (1) increasing the area of wetlands to their 1879 footprint and bathymetry, but leaving deep shipping channels unaltered; (2) shallowing all areas deeper than 2 m in the bay to be 2 m below Mean …
Can Tidal Perturbations Associated With Sea Level Variations In The Western Pacific Ocean Be Used To Understand Future Effects Of Tidal Evolution?, Adam T. Devlin, David A. Jay, Stefan A. Talke, Edward D. Zaron
Can Tidal Perturbations Associated With Sea Level Variations In The Western Pacific Ocean Be Used To Understand Future Effects Of Tidal Evolution?, Adam T. Devlin, David A. Jay, Stefan A. Talke, Edward D. Zaron
Civil and Environmental Engineering Faculty Publications and Presentations
This study examines connections between mean sea level (MSL) variability and diurnal and semidiurnal tidal constituent variations at 17 open-ocean and 9 continental shelf tide gauges in the western tropical Pacific Ocean, a region showing anomalous rise in MSL over the last 20 years and strong interannual variability. Detrended MSL fluctuations are correlated with detrended tidal amplitude and phase fluctuations, defined as tidal anomaly trends (TATs), to quantify the response of tidal properties to MSL variation. About 20 significant amplitude and phase TATs are found for each of the two strongest tidal constituents, K1 (diurnal) and M2 (semidiurnal). …
An Analysis Of Secular Change In Tides At Open-Ocean Sites In The Pacific, Edward D. Zaron, David A. Jay
An Analysis Of Secular Change In Tides At Open-Ocean Sites In The Pacific, Edward D. Zaron, David A. Jay
Civil and Environmental Engineering Faculty Publications and Presentations
Hourly sea level is examined at 25 open-ocean stations in the Pacific Ocean with records longer than 30 yr. A search for trends finds that the amplitude of the dominant semidiurnal tide M2 is increasing at 12 of the 13 sites where a statistically significant trend can be identified. It is also found that nontidal variance in the neighborhood of M2 is decreasing at all 12 of the sites where a significant increase in M2 tide is occurring. The trend in amplitude of the dominant diurnal tide K1 is significant at six stations, and it is …
Increasing Storm Tides In New York Harbor, 1844–2013, Stefan A. Talke, Philip M. Orton, David A. Jay
Increasing Storm Tides In New York Harbor, 1844–2013, Stefan A. Talke, Philip M. Orton, David A. Jay
Civil and Environmental Engineering Faculty Publications and Presentations
Three of the nine highest recorded water levels in the New York Harbor region have occurred since 2010 (March 2010, August 2011, and October 2012), and eight of the largest twenty have occurred since 1990. To investigate whether this cluster of high waters is a random occurrence or indicative of intensified storm tides, we recover archival tide gauge data back to 1844 and evaluate the trajectory of the annual maximum storm tide. Approximately half of long-term variance is anticorrelated with decadal-scale variations in the North Atlantic Oscillation, while long-term trends explain the remainder. The 10 year storm tide has increased …
Time-Variable Refraction Of The Internal Tide At The Hawaiian Ridge, Edward D. Zaron, Gary D. Egbert
Time-Variable Refraction Of The Internal Tide At The Hawaiian Ridge, Edward D. Zaron, Gary D. Egbert
Civil and Environmental Engineering Faculty Publications and Presentations
The interaction of the dominant semidiurnal M2 internal tide with the large-scale subtidal flow is examined in an ocean model by propagating the tide through an ensemble of background fields in a domain centered on the Hawaiian Ridge. The background fields are taken from the Simple Ocean Data Assimilation (SODA) ocean analysis, at 2-month intervals from 1992 through 2001. Tides are computed with the Primitive Equation Z-coordinate Harmonic Analysis of Tides (PEZ-HAT) model by 14-day integrations using SODA initial conditions and M2 tidal forcing. Variability of the tide is found to occur primarily as the result of propagation through …
Adaptation Of Classical Tidal Harmonic Analysis To Nonstationary Tides, With Application To River Tides, Pascal Matte, David A. Jay, Edward D. Zaron
Adaptation Of Classical Tidal Harmonic Analysis To Nonstationary Tides, With Application To River Tides, Pascal Matte, David A. Jay, Edward D. Zaron
Civil and Environmental Engineering Faculty Publications and Presentations
One of the most challenging areas in tidal analysis is the study of nonstationary signals with a tidal component, as they confront both current analysis methods and dynamical understanding. A new analysis tool has been developed, NS_TIDE, adapted to the study of nonstationary signals, in this case, river tides. It builds the nonstationary forcing directly into the tidal basis functions. It is implemented by modification of T_TIDE; however, certain concepts, particularly the meaning of a constituent and the Rayleigh criterion, are redefined to account for the smearing effects on the tidal spectral lines by nontidal energy. An error estimation procedure …
Influence Of Oceanic Forcing On Fate Of Nutrients In A Near-Shore-Aquifer, Nawrin Anwar
Influence Of Oceanic Forcing On Fate Of Nutrients In A Near-Shore-Aquifer, Nawrin Anwar
Electronic Thesis and Dissertation Repository
A reactive groundwater transport model has been developed to investigate the fate of nutrients (ammonium, nitrate, and phosphate) in a near-shore coastal aquifer subject to oceanic forcing (tides and waves) and their subsequent discharge to coastal waters. The model is developed by combining the variable-density groundwater flow model SEAWAT-2005 with the reactive multi-component transport model PHT3D v2.10. The influence of tides and waves are typically neglected in prior studies that have examined the transport and transformation of nutrients in coastal aquifers. Oceanic forcing however can induce a highly dynamic surficial salt-freshwater mixing and reaction zone in a near-shore aquifer and …