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A Regional, Early Spring Bloom Of Phaeocystis Pouchetii On The New England Continental Shelf, Walker O. Smith Jr., Weifeng G. Zhang, Andrew Hirzel, Et Al
A Regional, Early Spring Bloom Of Phaeocystis Pouchetii On The New England Continental Shelf, Walker O. Smith Jr., Weifeng G. Zhang, Andrew Hirzel, Et Al
VIMS Articles
The genus Phaeocystis is distributed globally and has considerable ecological, biogeochemical, and societal impacts. Understanding its distribution, growth and ecological impacts has been limited by lack of extensive observations on appropriate scales. In 2018, we investigated the biological dynamics of the New England continental shelf and encountered a substantial bloom of Phaeocystis pouchetii. Based on satellite imagery during January through April, the bloom extended over broad expanses of the shelf; furthermore, our observations demonstrated that it reached high biomass levels, with maximum chlorophyll concentrations exceeding 16 μg L−1 and particulate organic carbon levels > 95 μmol L−1. Initially, the bloom was …
Effects Of Reduced Shoreline Erosion On Chesapeake Bay Water Clarity, Jessica S. Turner, Pierre St-Laurent, Marjorie A.M. Friedrichs, Carl T. Friedrichs
Effects Of Reduced Shoreline Erosion On Chesapeake Bay Water Clarity, Jessica S. Turner, Pierre St-Laurent, Marjorie A.M. Friedrichs, Carl T. Friedrichs
VIMS Articles
Shoreline erosion supplies sediments to estuaries and coastal waters, influencing water clarity and primary production. Globally, shoreline erosion sediment inputs are changing with anthropogenic alteration of coastlines in populated regions. Chesapeake Bay, a prime example of such a system where shoreline erosion accounts for a large proportion of sediments entering the estuary, serves here as a case study for investigating the effects of changing sediment inputs on water clarity. Long-term increases in shoreline armoring have contributed to decreased erosional sediment inputs to the estuary, changing the composition of suspended particles in surface waters. This study examined the impact of shoreline …
Diatom Hotspots Driven By Western Boundary Current Instability, Hilde Oliver, Weifeng G. Zhang, Walker O. Smith Jr., Et Al
Diatom Hotspots Driven By Western Boundary Current Instability, Hilde Oliver, Weifeng G. Zhang, Walker O. Smith Jr., Et Al
VIMS Articles
Climatic changes have decreased the stability of the Gulf Stream (GS), increasing the frequency at which its meanders interact with the Mid-Atlantic Bight (MAB) continental shelf and slope region. These intrusions are thought to suppress biological productivity by transporting low-nutrient water to the otherwise productive shelf edge region. Here we present evidence of widespread, anomalously intense subsurface diatom hotspots in the MAB slope sea that likely resulted from a GS intrusion in July 2019. The hotspots (at ∼50 m) were associated with water mass properties characteristic of GS water (∼100 m); it is probable that the hotspots resulted from the …
Long-Term Trends In Chesapeake Bay Remote Sensing Reflectance: Implications For Water Clarity, Jessica S. Turner, Carl T. Friedrichs, Marjorie A.M. Friedrichs
Long-Term Trends In Chesapeake Bay Remote Sensing Reflectance: Implications For Water Clarity, Jessica S. Turner, Carl T. Friedrichs, Marjorie A.M. Friedrichs
VIMS Articles
While ecosystem health is improving in many estuaries worldwide following nutrient reductions, inconsistent trends in water clarity often remain. The Chesapeake Bay, a eutrophic estuary with a highly populated watershed, is a crucial testbed for these concerns. Improved efforts are needed to understand why some measurements of downstream estuarine water clarity appear to be uncorrelated with watershed management actions, and multiple metrics of clarity are needed to address this issue. To complement in situ measurements, satellite remote sensing provides an additional tool with which to assess long-term change in water clarity. In this study, remote sensing reflectance (Rrs) from the …
Sea Ice Suppression Of Co2 Outgassing In The West Antarctic Peninsula: Implications For The Evolving Southern Ocean Carbon Sink, E.H. Shadwick, O.A. De Meo, S. Schroeter, M.C. Arroyo, D.G. Martinson, H. Ducklow
Sea Ice Suppression Of Co2 Outgassing In The West Antarctic Peninsula: Implications For The Evolving Southern Ocean Carbon Sink, E.H. Shadwick, O.A. De Meo, S. Schroeter, M.C. Arroyo, D.G. Martinson, H. Ducklow
VIMS Articles
The Southern Ocean plays an important role in the uptake of atmospheric CO2. In seasonally ice-covered regions, estimates of air-sea exchange remain uncertain in part because of a lack of observations outside the summer season. Here we present new estimates of air-sea CO2 flux in the West Antarctic Peninsula (WAP) from an autonomous mooring on the continental shelf. In summer, the WAP is a sink for atmospheric CO2 followed by a slow return to atmospheric equilibrium in autumn and winter. Outgassing is almost entirely suppressed by ice cover from June through October, resulting in a modest …
Sea-Ice Microbial Communities In The Central Arctic Ocean: Limited Responses To Short-Term Pco(2) Perturbations, Anders Torstensson, Andrew R. Margolin, Gordon M. Showalter, Walker O. Smith Jr., Elizabeth H. Shadwick, Et Al
Sea-Ice Microbial Communities In The Central Arctic Ocean: Limited Responses To Short-Term Pco(2) Perturbations, Anders Torstensson, Andrew R. Margolin, Gordon M. Showalter, Walker O. Smith Jr., Elizabeth H. Shadwick, Et Al
VIMS Articles
The Arctic Ocean is more susceptible to ocean acidification than other marine environments due to its weaker buffering capacity, while its cold surface water with relatively low salinity promotes atmospheric CO 2 uptake. We studied how sea-ice microbial communities in the central Arctic Ocean may be affected by changes in the carbonate system expected as a consequence of ocean acidification. In a series of four experiments during late summer 2018 aboard the icebreaker Oden, we addressed microbial growth, production of dissolved organic carbon (DOC) and extra- cellular polymeric substances (EPS), photosynthetic activity, and bacterial assemblage structure as sea-ice microbial communities …
The Importance Of Organic Content To Fractal Floc Properties In Estuarine Surface Waters: Insights From Video, Lisst, And Pump Sampling, Kelsey A. Fall, Carl T. Friedrichs, Grace M. Massey, David G. Bowers, S. Jarrell Smith
The Importance Of Organic Content To Fractal Floc Properties In Estuarine Surface Waters: Insights From Video, Lisst, And Pump Sampling, Kelsey A. Fall, Carl T. Friedrichs, Grace M. Massey, David G. Bowers, S. Jarrell Smith
VIMS Articles
To better understand the nature of flocs of varying organic content in estuarine surface waters, Laser in situ Scattering and Transmissometry, video settling, and pump sampling were deployed in the York River estuary. A new in situ method was developed to simultaneously solve the floc fractal dimension (F), primary particle size (d p ), and primary particle density (ρ p ) by fitting a simple fractal model to observations of effective floc density (∆ρ) as a function of floc diameter (d f ), while ensuring that the integrated particle size distribution was consistent with measurements of bulk apparent density (ρ …
Revisiting The Ocean Color Algorithms For Particulate Organic Carbon And Chlorophyll-A Concentrations In The Ross Sea, Shuangling Chen, Walker O. Smith Jr., Xiaolei Yu
Revisiting The Ocean Color Algorithms For Particulate Organic Carbon And Chlorophyll-A Concentrations In The Ross Sea, Shuangling Chen, Walker O. Smith Jr., Xiaolei Yu
VIMS Articles
The Ross Sea is the most productive marginal sea in the Southern Ocean and plays an important role in carbon cycling. However, limited sampling of Chlorophyll-a (Chl) and particulate organic carbon (POC) concentrations from research expeditions constrains our understanding of the biogeochemical processes there. Satellites provide a useful tool for synoptic mapping of surface water properties on regional and global scales, yet the general applicability of the published algorithms in the Ross Sea is poorly known. Based on the data collected from 18 cruises in the past 20 years, we analyzed both the NASA standard and locally developed Chl and …
Exchange Flow And Material Transport Along The Salinity Gradient Of A Long Estuary, Jilian Xiong, Jian Shen, Qubin Qin
Exchange Flow And Material Transport Along The Salinity Gradient Of A Long Estuary, Jilian Xiong, Jian Shen, Qubin Qin
VIMS Articles
Most estuaries are characterized by non-uniform axial topography with shallow shoals near the mouth. Previous studies have addressed the impacts of the axial topographic variations on mixing and estuarine circulations yet seldom on material transport and retention. This study investigates the longitudinal structure and mechanisms of exchange flow and material transport of Chesapeake Bay (CB), featuring a shallow sill in the lower bay, by applying total exchange flow (TEF) algorithm, tracer experiments, and partial residence time (PRT) using a validated 32-years numerical model simulation. A retention coefficient was adopted to quantify the material retention rate using two characteristic PRTs: with …
A Modeling Study On The Influence Of Sea-Level Rise And Channel Deepening On Estuarine Circulation And Dissolved Oxygen Levels In The Tidal James River, Virginia, Usa, Ya Wang, Jian Shen
A Modeling Study On The Influence Of Sea-Level Rise And Channel Deepening On Estuarine Circulation And Dissolved Oxygen Levels In The Tidal James River, Virginia, Usa, Ya Wang, Jian Shen
VIMS Articles
The impact of channel deepening and sea-level rise on the environmental integrity of an estuary is investigated using a three-dimensional hydrodynamic-eutrophication model. The model results show that dissolved oxygen (DO) only experienced minor changes, even when the deep channel was deepened by 3 m in the mesohaline and polyhaline regions of the James River. We found that vertical stratification decreased DO aeration while the estuarine gravitational circulation increased bottom DO exchange. The interactions between these two processes play an important role in modulating DO. The minor change in DO due to channel deepening indicates that the James River is unique …
A Database Of Ocean Primary Productivity From The 14c Method, J. F. Marra, R. T. Barber, (...), Walker O. Smith Jr., L. Zoffli
A Database Of Ocean Primary Productivity From The 14c Method, J. F. Marra, R. T. Barber, (...), Walker O. Smith Jr., L. Zoffli
VIMS Articles
The database on ocean primary productivity comprises over two decades (1985–2008) of data that the authors have participated in collecting, using the assimilation of inorganic 14C through photosynthesis, in incubations carried out in situ. The dataset is perhaps unique in that it uses, overwhelmingly, consistent methodology while covering a wide geographic range. Ancillary data are included. Using the database, it is hoped that investigators can test for the relationships among the environmental drivers for ocean productivity, the meaning of the 14C method in terms of phytoplankton physiology and the dynamics in the water column, and as a resource …
Ocean_Data_Tools: A Matlab Toolbox For Interacting With Bulk Freely-Available Oceanographic Data, Laur Ferris
Ocean_Data_Tools: A Matlab Toolbox For Interacting With Bulk Freely-Available Oceanographic Data, Laur Ferris
VIMS Articles
ocean_data_tools simplifies the process of extracting, formatting, and visualizing freely-available oceanographic data. A wealth of oceanographic data (from research cruises, autonomous floats, global ocean models, etc.) is accessible online. However, many oceanographers and environmental scientists (particularly those from subdisciplines not accustomed to working with large datasets) can be dissuaded from utilizing this data because of the overhead associated with determining how to batch download data and format it into easily-manipulable data structures. ocean_data_tools solves this problem by allowing the user to transform common oceanographic data sources into uniform structure arrays, call general functions on these structure arrays, perform custom calculations, …
Climate-Induced Variability In South Atlantic Wave Direction Over The Past Three Millennia, A. P. Silva, A. H. F. Klein, A. F. H. Fetter-Filho, Christopher J. Hein, Et Al
Climate-Induced Variability In South Atlantic Wave Direction Over The Past Three Millennia, A. P. Silva, A. H. F. Klein, A. F. H. Fetter-Filho, Christopher J. Hein, Et Al
VIMS Articles
Through alteration of wave-generating atmospheric systems, global climate changes play a fundamental role in regional wave climate. However, long-term wave-climate cycles and their associated forcing mechanisms remain poorly constrained, in part due to a relative dearth of highly resolved archives. Here we use the morphology of former shorelines preserved in beach-foredune ridges (BFR) within a protected embayment to reconstruct changes in predominant wave directions in the Subtropical South Atlantic during the last ~ 3000 years. These analyses reveal multi-centennial cycles of oscillation in predominant wave direction in accordance with stronger (weaker) South Atlantic mid- to high-latitudes mean sea-level pressure gradient …
A Continental Shelf Pump For Co2 On The Adélie Land Coast, East Antarctica, Mar C. Arroyo, Elizabeth H. Shadwick, Stephen R. Rintoul, Kazuya Kusahara
A Continental Shelf Pump For Co2 On The Adélie Land Coast, East Antarctica, Mar C. Arroyo, Elizabeth H. Shadwick, Stephen R. Rintoul, Kazuya Kusahara
VIMS Articles
We quantify the transport of inorganic carbon from the continental shelf to the deep ocean in Dense Shelf Water (DSW) from the Mertz and Ninnis Polynyas along the Adélie Land coast in East Antarctica. For this purpose, observations of total dissolved inorganic carbon (TCO2) from two summer hydrographic surveys in 2015 and 2017 were paired with DSW volume transport estimates derived from a coupled ocean‐sea ice‐ice shelf model to examine the fate of inorganic carbon in DSW from Adélie Land. Transports indicate a net outflow of 227 ± 115 Tg C yr−1 with DSW in the postglacial …
Estuarine Forecasts At Daily Weather To Subseasonal Time Scales, Andrew C. Ross, Charles A. Stock, Keith W. Dixon, Marjorie A.M. Friedrichs, Et Al
Estuarine Forecasts At Daily Weather To Subseasonal Time Scales, Andrew C. Ross, Charles A. Stock, Keith W. Dixon, Marjorie A.M. Friedrichs, Et Al
VIMS Articles
Most present forecast systems for estuaries predict conditions for only a few days into the future. However, there are many reasons to expect that skillful estuarine forecasts are possible for longer time periods, including increasingly skillful extended atmospheric forecasts, the potential for lasting impacts of atmospheric forcing on estuarine conditions, and the predictability of tidal cycles. In this study, we test whether skillful estuarine forecasts are possible for up to 35 days into the future by combining an estuarine model of Chesapeake Bay with 35-day atmospheric forecasts from an operational weather model. When compared with both a hindcast simulation from …
Data-Driven, Multi-Model Workflow Suggests Strong Influence From Hurricanes On The Generation Of Turbidity Currents In The Gulf Of Mexico, Courtney K. Harris, Jaia Syvitski, H. G. Arango, Et Al
Data-Driven, Multi-Model Workflow Suggests Strong Influence From Hurricanes On The Generation Of Turbidity Currents In The Gulf Of Mexico, Courtney K. Harris, Jaia Syvitski, H. G. Arango, Et Al
VIMS Articles
Turbidity currents deliver sediment rapidly from the continental shelf to the slope and beyond; and can be triggered by processes such as shelf resuspension during oceanic storms; mass failure of slope deposits due to sediment- and wave-pressure loadings; and localized events that grow into sustained currents via self-amplifying ignition. Because these operate over multiple spatial and temporal scales, ranging from the eddy-scale to continental-scale; coupled numerical models that represent the full transport pathway have proved elusive though individual models have been developed to describe each of these processes. Toward a more holistic tool, a numerical workflow was developed to address …
The Impact Of Winter Storms On Sediment Transport Through A Narrow Strait, Bohai, China, Chenghao Wang, Zhiqiang Liu, Courtney K. Harris, Et Al
The Impact Of Winter Storms On Sediment Transport Through A Narrow Strait, Bohai, China, Chenghao Wang, Zhiqiang Liu, Courtney K. Harris, Et Al
VIMS Articles
The Yellow River is one of the most significant sources of terrestrial sediment to the global seas, and the Bohai Strait is the only pathway that delivers Yellow River‐derived sediments from the shallow Bohai Sea to the Yellow Sea. To investigate sediment transport processes through the strait under the influence of storms (strong northerly winds) that frequently occur in winter, we deployed two sets of observing platforms equipped with Acoustic Doppler Current Profilers (ADCP) and a suite of other sensors in the strait in January 2018. Aided by a system of high‐resolution models, we reconstructed sediment dynamics in response to …
Representing The Function And Sensitivity Of Coastal Interfaces In Earth System Models, Nd Ward, Jp Megonigal, B Bond-Lamberty, Vl Bailey, D Butman, Elizabeth A. Canuel, Et Al
Representing The Function And Sensitivity Of Coastal Interfaces In Earth System Models, Nd Ward, Jp Megonigal, B Bond-Lamberty, Vl Bailey, D Butman, Elizabeth A. Canuel, Et Al
VIMS Articles
Between the land and ocean, diverse coastal ecosystems transform, store, and transport material. Across these interfaces, the dynamic exchange of energy and matter is driven by hydrological and hydrodynamic processes such as river and groundwater discharge, tides, waves, and storms. These dynamics regulate ecosystem functions and Earth's climate, yet global models lack representation of coastal processes and related feedbacks, impeding their predictions of coastal and global responses to change. Here, we assess existing coastal monitoring networks and regional models, existing challenges in these efforts, and recommend a path towards development of global models that more robustly reflect the coastal interface. …
Providential Tides: The Double Low Water Of Narragansett Bay, D. G. Bowers, J. M. Brubaker
Providential Tides: The Double Low Water Of Narragansett Bay, D. G. Bowers, J. M. Brubaker
VIMS Articles
We investigate a mechanism for producing double-lows and double-highs in the semi-diurnal tide by selective amplification of higher harmonics in a resonant gulf. A double low water is observed at Providence, RI, near the head of Narragansett Bay on days when there is a flattening of the low water tidal curve at Newport, at the mouth of the bay. The flattening is caused by an unusually large quarter-diurnal component to the tide at Newport. The quarter diurnal component has the right phase (a maximum close to the time of the minimum in the semi-diurnal tide) to produce a prolonged flattening …
Massive Pollutants Released To Galveston Bay During Hurricane Harvey: Understanding Their Retention And Pathway Using Lagrangian Numerical Simulations, Jiabi Du, Kyeong Park, Xin Yu, Yinglong J. Zhang, Fei Ye
Massive Pollutants Released To Galveston Bay During Hurricane Harvey: Understanding Their Retention And Pathway Using Lagrangian Numerical Simulations, Jiabi Du, Kyeong Park, Xin Yu, Yinglong J. Zhang, Fei Ye
VIMS Articles
Increasing frequency of extreme precipitation events under the future warming climate makes the storm-related pollutant release more and more threatening to coastal ecosystems. Hurricane Harvey, a 1000-year extreme precipitation event, caused massive pollutant release from the Houston metropolitan area to the adjacent Galveston Bay. 0.57 × 106 tons of raw sewage and 22,000 barrels of oil, refined fuels and chemicals were reportly released during Harvey, which would likely deteriorate the water quality and damage the coastal ecosystem. Using a Lagrangian particle-tracking method coupled with a validated 3D hydrodynamic model, we examined the retention, pathway, and fate of the released …
Response Of Stratification Processes To Tidal Current Alteration Due To Channel Narrowing And Deepening, Lei Zhu, Qing He, Jian Shen
Response Of Stratification Processes To Tidal Current Alteration Due To Channel Narrowing And Deepening, Lei Zhu, Qing He, Jian Shen
VIMS Articles
Stratification in estuaries has received much focus due to its importance in estuarine hydrodynamics and material transport. By utilizing a well‐calibrated numerical model, in this work we investigate the changes in stratification in the deepened and narrowed North Passage of the Changjiang Estuary. Before channel narrowing and deepening, lateral straining, generated by the interaction between vertical shear in lateral flow and transverse salinity gradient, is the dominant factor that controls stratification. A two‐layer structure of the lateral flow strains the isopycnal transversely, resulting in rapid stratification from late flood to early ebb tide. Thus, maximum stratification occurs during the early …
Seasonal Variability Of The Co2 System In A Large Coastal Plain Estuary, Jaclyn R. Friedman, Elizabeth H. Shadwick, Marjorie A.M. Friedrichs, Raymond G. Najjar, Olivia A. De Meo, Fei Da, Juliette L. Smith
Seasonal Variability Of The Co2 System In A Large Coastal Plain Estuary, Jaclyn R. Friedman, Elizabeth H. Shadwick, Marjorie A.M. Friedrichs, Raymond G. Najjar, Olivia A. De Meo, Fei Da, Juliette L. Smith
VIMS Articles
The Chesapeake Bay, a large coastal plain estuary, has been studied extensively in terms of its water quality, and yet, comparatively less is known about its carbonate system. Here we present discrete observations of dissolved inorganic carbon (DIC) and total alkalinity from four seasonal cruises in 2016–2017. These new observations are used to characterize the regional CO2 system and to construct a DIC budget of the mainstem. In all seasons, elevated DIC concentrations were observed at the mouth of the bay associated with inflowing Atlantic Ocean waters, while minimum concentrations of DIC were associated with fresher waters at the …
Saildrone: Adaptively Sampling The Marine Environment, C. L. Gentemann, Joel P. Scott, Piero L. F. Mazzini, Cassia Pianca, Et Al
Saildrone: Adaptively Sampling The Marine Environment, C. L. Gentemann, Joel P. Scott, Piero L. F. Mazzini, Cassia Pianca, Et Al
VIMS Articles
From 11 April to 11 June 2018 a new type of ocean observing platform, the Saildrone surface vehicle, collected data on a round-trip, 60-day cruise from San Francisco Bay, down the U.S. and Mexican coast to Guadalupe Island. The cruise track was selected to optimize the science team’s validation and science objectives. The validation objectives include establishing the accuracy of these new measurements. The scientific objectives include validation of satellite-derived fluxes, sea surface temperatures, and wind vectors and studies of upwelling dynamics, river plumes, air–sea interactions including frontal regions, and diurnal warming regions. On this deployment, the Saildrone carried 16 …
Simulating Storm Surge And Compound Flooding Events With A Creek-To-Ocean Model: Importance Of Baroclinic Effects, Fei Ye, Yinglong J. Zhang, Haocheng Yu, Weiling Sun, Saeed Moghimi, Edward Myers, Karinna Nunez, Ruoyin Zhang, Harry V. Wang, Aron Roland, Kevin Martins, Xavier Bertin, Jiabi Du, Zhou Liiu
Simulating Storm Surge And Compound Flooding Events With A Creek-To-Ocean Model: Importance Of Baroclinic Effects, Fei Ye, Yinglong J. Zhang, Haocheng Yu, Weiling Sun, Saeed Moghimi, Edward Myers, Karinna Nunez, Ruoyin Zhang, Harry V. Wang, Aron Roland, Kevin Martins, Xavier Bertin, Jiabi Du, Zhou Liiu
VIMS Articles
We present a creek-to-ocean 3D baroclinic model based on unstructured grids that aims to unite traditional hydrologic and ocean models in a single modeling platform, by taking full advantage of the polymorphism (i.e. a single model grid can seamlessly morph between full 3D, 2DV, 2DH and quasi-1D configurations). Using Hurricane Irene (2011)'s impact on the Delaware Bay as an example, a seamless 2D-3D model grid is implemented to include the entire US East Coast and Gulf of Mexico with a highly resolved Delaware Bay (down to 20-m resolution). The model is forced by flows from a hydrological model (National Water …
Potential Physical Impacts Of Sea-Level Rise On The Pearl River Estuary, China, Bo Hong, Zhonghui Liu, Jian Shen, Hui Wu, Wenping Gong, Hongzhou Xu, Dongxiao Wang
Potential Physical Impacts Of Sea-Level Rise On The Pearl River Estuary, China, Bo Hong, Zhonghui Liu, Jian Shen, Hui Wu, Wenping Gong, Hongzhou Xu, Dongxiao Wang
VIMS Articles
The response of a coastal region to sea-level rise depends on the local physical features, which should therefore be evaluated locally to provide an accurate vulnerability assessment. In this study, we conducted comprehensive analyses of the potential impacts of sea-level rise on the Pearl River Estuary (PRE), China with the aid of a fully calibrated three-dimensional hydrodynamic model. We found that in general, the salinity, stratification and tidal range will increase as the sea-level rises. Clear spatial variations were apparent in the response of these parameters, with different patterns occurring in different seasons. The strongest salinity increase was mostly at …
Secchi Disk Measurements In Turbid Water, D. G. Bowers, E M. Roberts, A. M. Hoguane, K A. Fall, Grace M. Massey, Carl T. Friedrichs
Secchi Disk Measurements In Turbid Water, D. G. Bowers, E M. Roberts, A. M. Hoguane, K A. Fall, Grace M. Massey, Carl T. Friedrichs
VIMS Articles
In the classical theory of the Secchi disk depth, diffuse sunlight falling on the disk is reflected back to the observer’s eye along the most direct route, as a beam. The disappearance depth, ZSD, of the disk is then expected to vary inversely with the sum of the beam and diffuse attenuation coefficients: c+KD. Observations presented here show that, in the most turbid waters sampled, the Secchi disk is visible at greater depths (by a factor of up to 4) than predicted by this theory. In these conditions, the disk appears blurry and it seems likely that some of the …
Role Of Delta-Front Erosion In Sustaining Salt Marshes Under Sea-Level Rise And Fluvial Sediment Decline, Shi Lun Yang, Xiangxin Luo, Stijn Temmerman, Matthew L. Kirwan, Et Al
Role Of Delta-Front Erosion In Sustaining Salt Marshes Under Sea-Level Rise And Fluvial Sediment Decline, Shi Lun Yang, Xiangxin Luo, Stijn Temmerman, Matthew L. Kirwan, Et Al
VIMS Articles
Accelerating sea-level rise and decreasing riverine sediment supply are widely considered to lead to global losses of deltaic marshes and their valuable ecosystem services. However, little is known about the degree to which the related erosion of the seaward delta front can provide sediments to sustain salt marshes. Here, we present dataf rom the mesomacrotidal Yangtze Delta demonstrating that marshes have continued to accrete vertically and laterally, despite rapid relative sea-level rise (approx.10 mm yr−1) and a > 70% decrease in the Yangtze River sediment supply. Marsh progradation has decelerated at a lower rate than fluvial sediment reduction, suggesting an additional …
Annual And Seasonal Surface Circulation Over The Mid-Atlantic Bight Continental Shelf Derived From A Decade Of High Frequency Radar Observations, Hugh Roarty, Scott Glenn, Et Al, Haixing Wang, Donglai Gong
Annual And Seasonal Surface Circulation Over The Mid-Atlantic Bight Continental Shelf Derived From A Decade Of High Frequency Radar Observations, Hugh Roarty, Scott Glenn, Et Al, Haixing Wang, Donglai Gong
VIMS Articles
A decade (2007–2016) of hourly 6-km-resolution maps of the surface currents across the Mid-Atlantic Bight (MAB) generated by a regional scale High Frequency Radar network are used to reveal new insights into the spatial patterns of the annual and seasonal mean surface flows. Across the 10-year time series, temporal means and interannual and intra-annual variability are used to quantify the variability of spatial surface current patterns. The 10-year annual mean surface flows are weaker and mostly cross-shelf near the coast, increasing in speed and rotating to more alongshore directions near the shelfbreak, and increasing in speed and rotating to flow …
Asynchronous Nitrogen Supply And Demand Produce Nonlinear Plant Allocation Responses To Warming And Elevated Co2, Genevieve L. Noyce, Matthew L. Kirwan, Roy L. Rich, J. Patrick Megonigal
Asynchronous Nitrogen Supply And Demand Produce Nonlinear Plant Allocation Responses To Warming And Elevated Co2, Genevieve L. Noyce, Matthew L. Kirwan, Roy L. Rich, J. Patrick Megonigal
VIMS Articles
Terrestrial ecosystem responses to climate change are mediated by complex plant–soil feedbacks that are poorly understood, but often driven by the balance of nutrient supply and demand. We actively increased aboveground plant-surface temperature, belowground soil temperature, and atmospheric CO2 in a brackish marsh and found nonlinear and nonadditive feedbacks in plant responses. Changes in root-to-shoot allocation by sedges were nonlinear, with peak belowground allocation occurring at +1.7 °C in both years. Above 1.7 °C, allocation to root versus shoot production decreased with increasing warming such that there were no differences in root biomass between ambient and +5.1 °C plots …
Scientific Considerations For Acidification Monitoring In The Us Mid-Atlantic Region, Ka Goldsmith, S Lau, Et Al, Eh Shadwick, Et Al
Scientific Considerations For Acidification Monitoring In The Us Mid-Atlantic Region, Ka Goldsmith, S Lau, Et Al, Eh Shadwick, Et Al
VIMS Articles
Coastal and ocean acidification has the potential to cause significant environmental and societal impacts. Monitoring carbonate chemistry parameters over spatial and temporal scales is challenging, especially with limited resources. A lack of monitoring data can lead to a limited understanding of real-world conditions. Without such data, robust experimental and model design is challenging, and the identification and understanding of episodic acidification events is nearly impossible. We present considerations for resource managers, academia, and industry professionals who are currently developing acidification monitoring programs in the Mid-Atlantic region. We highlight the following considerations for deliberation: 1) leverage existing infrastructure to include multiple …