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Global Perspectives On Observing Ocean Boundary Current Systems, Robert E. Todd, Francisco P. Chavez, Sophie Clayton, Sophie Cravatte, Marlos Goes, Michelle Graco, Xiaopei Lin, Janet Sprintall, Nathalie V. Zilberman, Matthew Archer, Javier Arístegui, Magdalena Balmaseda, John M. Bane, Molly O. Baringer, John A. Barth, Lisa M. Beal, Peter Brandt, Paulo H.R. Calil, Edmo Campos, Luca R. Centurioni, Maria Paz Chidichimo, Mauro Cirano, Meghan F. Cronin, Enrique N. Curchitser, Russ E. Davis, Marcus Dengler, Brad Deyoung, Shenfu Dong, Ruben Escribano, Andrea J. Fassbender, Sarah E. Fawcett, Ming Feng, Gustavo J. Goni, Alison R. Gray, Dimitri Gutiérrez, Dave Hebert, Rebecca Hummels, Shin-Ichi Ito, Marjorlaine Krug, François Lacan, Lucas Laurindo, Alban Lazar, Craig M. Lee, Matthieu Lengaigne, Naomi M. Levine, John Middleton, Ivonne Montes, Mike Muglia, Takeyoshi Nagai, Hilary I. Palevsky, Jaine B. Palter, Helen E. Phillips, Alberto Piola, Albert J. Plueddemann, Bo Qiu, Regina R. Rodrigues, Moninya Roughan, Daniel L. Rudnick, Ryan R. Rykaczewski, Martin Saraceno, Harvey Seim, Alex Sen Gupta, Lynne Shannon, Bernadette M. Sloyan, Adrienne J. Sutton, Luanne Thompson, Anja K. Van Der Plas, Denis Volkov, John Wilkin, Dongxiao Zhang, Linlin Zhang Jan 2019

Global Perspectives On Observing Ocean Boundary Current Systems, Robert E. Todd, Francisco P. Chavez, Sophie Clayton, Sophie Cravatte, Marlos Goes, Michelle Graco, Xiaopei Lin, Janet Sprintall, Nathalie V. Zilberman, Matthew Archer, Javier Arístegui, Magdalena Balmaseda, John M. Bane, Molly O. Baringer, John A. Barth, Lisa M. Beal, Peter Brandt, Paulo H.R. Calil, Edmo Campos, Luca R. Centurioni, Maria Paz Chidichimo, Mauro Cirano, Meghan F. Cronin, Enrique N. Curchitser, Russ E. Davis, Marcus Dengler, Brad Deyoung, Shenfu Dong, Ruben Escribano, Andrea J. Fassbender, Sarah E. Fawcett, Ming Feng, Gustavo J. Goni, Alison R. Gray, Dimitri Gutiérrez, Dave Hebert, Rebecca Hummels, Shin-Ichi Ito, Marjorlaine Krug, François Lacan, Lucas Laurindo, Alban Lazar, Craig M. Lee, Matthieu Lengaigne, Naomi M. Levine, John Middleton, Ivonne Montes, Mike Muglia, Takeyoshi Nagai, Hilary I. Palevsky, Jaine B. Palter, Helen E. Phillips, Alberto Piola, Albert J. Plueddemann, Bo Qiu, Regina R. Rodrigues, Moninya Roughan, Daniel L. Rudnick, Ryan R. Rykaczewski, Martin Saraceno, Harvey Seim, Alex Sen Gupta, Lynne Shannon, Bernadette M. Sloyan, Adrienne J. Sutton, Luanne Thompson, Anja K. Van Der Plas, Denis Volkov, John Wilkin, Dongxiao Zhang, Linlin Zhang

OES Faculty Publications

Ocean boundary current systems are key components of the climate system, are home to highly productive ecosystems, and have numerous societal impacts. Establishment of a global network of boundary current observing systems is a critical part of ongoing development of the Global Ocean Observing System. The characteristics of boundary current systems are reviewed, focusing on scientific and societal motivations for sustained observing. Techniques currently used to observe boundary current systems are reviewed, followed by a census of the current state of boundary current observing systems globally. Next steps in the development of boundary current observing systems are considered, leading to …


Seasonal Variability Of Forces Controlling Sedimentation In The Sundarbans National Forest, Bangladesh, Rip P. Hale, C. A. Wilson, E. J. Bomer Jan 2019

Seasonal Variability Of Forces Controlling Sedimentation In The Sundarbans National Forest, Bangladesh, Rip P. Hale, C. A. Wilson, E. J. Bomer

OES Faculty Publications

Southwest Bangladesh, located on the Ganges-Brahmaputra-Meghna delta, is experiencing the impacts of sea level rise (SLR) due to processes at both the local and global scale. In particular, regional alterations of the hydrodynamic network, due to embankment construction, have drastically altered effective SLR, placing millions of inhabitants at risk of prolonged inundation, and threatening the world’s largest continuous mangrove stand, the Sundarbans National Forest (SNF). In order to effectively employ landscape recovery solutions, an understanding of local sediment transport and deposition is critical. This field-based study investigates the sediment dynamics between the mangrove platform and tidal channels of the SNF …


Internal Waves Influence The Thermal And Nutrient Environment On A Shallow Coral Reef, Emma C. Reid, Thomas M. Decarlo, Anne L. Cohen, George T.F. Wong, Steven J. Lentz, Aryan Safaie, Austin Hall, Kristen A. Davis Jan 2019

Internal Waves Influence The Thermal And Nutrient Environment On A Shallow Coral Reef, Emma C. Reid, Thomas M. Decarlo, Anne L. Cohen, George T.F. Wong, Steven J. Lentz, Aryan Safaie, Austin Hall, Kristen A. Davis

OES Faculty Publications

Internal waves can influence water properties in coastal ecosystems through the shoreward transport and mixing of subthermocline water into the nearshore region. In June 2014, a field experiment was conducted at Dongsha Atoll in the northern South China Sea to study the impact of internal waves on a coral reef. Instrumentation included a distributed temperature sensing system, which resolved spatially and temporally continuous temperature measurements over a 4‐km cross‐reef section from the lagoon to 50‐m depth on the fore reef. Our observations show that during summer, internal waves shoaling on the shallow atoll regularly transport cold, nutrient‐rich water shoreward, altering …


Reconstruction Of Sea Level Around The Korean Peninsula Using Cyclostationary Empirical Orthogonal Functions, Se-Hyeon Cheon, Benjamin D. Hamlington, Kyung-Duck Suh Sep 2018

Reconstruction Of Sea Level Around The Korean Peninsula Using Cyclostationary Empirical Orthogonal Functions, Se-Hyeon Cheon, Benjamin D. Hamlington, Kyung-Duck Suh

OES Faculty Publications

Since the advent of the modern satellite altimeter era, the understanding of the sea level has increased dramatically. The satellite altimeter record, however, dates back only to the 1990s. The tide gauge record, on the other hand, extends through the 20th century but with poor spatial coverage when compared to the satellites. Many studies have been conducted to create a dataset with the spatial coverage of the satellite datasets and the temporal length of the tide gauge records by finding novel ways to combine the satellite data and tide gauge data in what is known as sea level reconstruction. However, …


Light Availability And Phytoplankton Growth Beneath Arctic Sea Ice: Integrating Observations And Modeling, Victoria J. Hill, Bonnie Light, Michael Steele, Richard C. Zimmerman May 2018

Light Availability And Phytoplankton Growth Beneath Arctic Sea Ice: Integrating Observations And Modeling, Victoria J. Hill, Bonnie Light, Michael Steele, Richard C. Zimmerman

OES Faculty Publications

Observations of the seasonal light field in the upper Arctic Ocean are critical to understanding the impacts of changing Arctic ice conditions on phytoplankton growth in the water column. Here we discuss data from a new sensor system, deployed in seasonal ice cover north‐east of Utqiaġvik, Alaska in March 2014. The system was designed to provide observations of light and phytoplankton biomass in the water column during the formation of surface melt ponds and the transition from ice to open water. Hourly observations of downwelling irradiance beneath the ice (at 2.9, 6.9, and 17.9 m depths) and phytoplankton biomass (at …


Observation-Driven Estimation Of The Spatial Variability Of 20th Century Sea Level Rise, B. D. Hamlington, A. Burgos, P. R. Thompson, F. W. Landerer, C. G. Piecuch, S. Adhikari, L. Caron, J. T. Reager, E. R. Ivins Jan 2018

Observation-Driven Estimation Of The Spatial Variability Of 20th Century Sea Level Rise, B. D. Hamlington, A. Burgos, P. R. Thompson, F. W. Landerer, C. G. Piecuch, S. Adhikari, L. Caron, J. T. Reager, E. R. Ivins

OES Faculty Publications

Over the past two decades, sea level measurements made by satellites have given clear indications of both global and regional sea level rise. Numerous studies have sought to leverage the modern satellite record and available historic sea level data provided by tide gauges to estimate past sea level rise, leading to several estimates for the 20th century trend in global mean sea level in the range between 1 and 2 mm/yr. On regional scales, few attempts have been made to estimate trends over the same time period. This is due largely to the inhomogeneity and quality of the tide …


Expected Limits On The Ocean Acidification Buffering Potential Of A Temperate Seagrass Meadow, David A. Koweek, R. C. Zimmerman, Kathryn M. Hewett, Brian Gaylord, Sarah N. Giddings, Kerry J. Nickols, Jennifer L. Ruesink, John J. Stachowicz, Yuichiro Takeshita, Ken Caldeira Jan 2018

Expected Limits On The Ocean Acidification Buffering Potential Of A Temperate Seagrass Meadow, David A. Koweek, R. C. Zimmerman, Kathryn M. Hewett, Brian Gaylord, Sarah N. Giddings, Kerry J. Nickols, Jennifer L. Ruesink, John J. Stachowicz, Yuichiro Takeshita, Ken Caldeira

OES Faculty Publications

Ocean acidification threatens many marine organisms, especially marine calcifiers. The only global‐scale solution to ocean acidification remains rapid reduction in CO2 emissions. Nevertheless, interest in localized mitigation strategies has grown rapidly because of the recognized threat ocean acidification imposes on natural communities, including ones important to humans. Protection of seagrass meadows has been considered as a possible approach for localized mitigation of ocean acidification due to their large standing stocks of organic carbon and high productivity. Yet much work remains to constrain the magnitudes and timescales of potential buffering effects from seagrasses. We developed a biogeochemical box model to …


Future Nuisance Flooding In Norfolk, Va, From Astronomical Tides And Annual To Decadal Internal Climate Variability, A. G. Burgos, B. D. Hamlington, P. R. Thompson, R. D. Ray Jan 2018

Future Nuisance Flooding In Norfolk, Va, From Astronomical Tides And Annual To Decadal Internal Climate Variability, A. G. Burgos, B. D. Hamlington, P. R. Thompson, R. D. Ray

OES Faculty Publications

Increasing sea level rise will lead to more instances of nuisance flooding along the Virginia coastline in the coming decades, causing road closures and deteriorating infrastructure. These minor flood events can be caused by astronomical tides alone, in addition to internal climate variability on annual to decadal timescales. An assessment of nuisance flooding from these two effects is presented up until the year 2050 for Norfolk, Virginia. The analysis of water levels indicates that nuisance flooding from tides alone in conjunction with a medium-high sea level scenario will result in flooding beginning in 2030 with frequency increasing thereafter. The addition …


Deglacial Tropical Atlantic Subsurface Warming Links Ocean Circulation Variability To The West African Monsoon, Matthew W. Schmidt, Ping Chang, Andrew O. Parker, Link Ji, Feng He Nov 2017

Deglacial Tropical Atlantic Subsurface Warming Links Ocean Circulation Variability To The West African Monsoon, Matthew W. Schmidt, Ping Chang, Andrew O. Parker, Link Ji, Feng He

OES Faculty Publications

Multiple lines of evidence show that cold stadials in the North Atlantic were accompanied by both reductions in Atlantic Meridional Overturning Circulation (AMOC) and collapses of the West African Monsoon (WAM). Although records of terrestrial change identify abrupt WAM variability across the deglaciation, few studies show how ocean temperatures evolved across the deglaciation. To identify the mechanism linking AMOC to the WAM, we generated a new record of subsurface temperature variability over the last 21 kyr based on Mg/Ca ratios in a sub-thermocline dwelling planktonic foraminifera in an Eastern Equatorial Atlantic (EEA) sediment core from the Niger Delta. Our subsurface …


Regional Sea Level Variability And Trends, 1960-2007: A Comparison Of Sea Level Reconstructions And Ocean Syntheses, M. Carson, A. Köhl, D. Stammer, B. Meyssignac, J. Church, J. Schröter, M. Wenzel, B. Hamlington Nov 2017

Regional Sea Level Variability And Trends, 1960-2007: A Comparison Of Sea Level Reconstructions And Ocean Syntheses, M. Carson, A. Köhl, D. Stammer, B. Meyssignac, J. Church, J. Schröter, M. Wenzel, B. Hamlington

OES Faculty Publications

Several existing statistical and dynamical reconstructions of past regional sea level variability and trends are compared with each other and with tide gauges over the 48 year period 1960-2007, partially predating the satellite altimetry era. Evaluated statistical reconstructions were built from tide-gauge data (TGR), and dynamical reconstructions from ocean data assimilation (ODA) approaches. Although most of the TGRs yield global-mean time series of sea level with trends deviating within ± 0.1 mm yr-1, the spatial anomalies of the trends deviate substantially between the reconstructions over the period predating altimetry. In contrast, TGRs match observed regional trend patterns fairly …


Origins And Transformations Of Dissolved Organic Matter In Large Arctic Rivers, Karl Kaiser, Maria Canedo-Oropeza, Rachel Mcmahon, Eainer M. W. Amon Oct 2017

Origins And Transformations Of Dissolved Organic Matter In Large Arctic Rivers, Karl Kaiser, Maria Canedo-Oropeza, Rachel Mcmahon, Eainer M. W. Amon

OES Faculty Publications

Arctic river watersheds are important components of the global climate system and show an amplified response to climate change. Here, we characterize origins and transformations of dissolved organic matter (DOM) in five major Arctic rivers (Kolyma, Lena, Yenisei, Ob, Mackenzie) over 3 years with seasonal sampling periods using measurements of carbohydrates, amino acids, bacterial biomarkers (D-amino acids), and plant protein biomarkers (hydroxyproline). A strong seasonal cycle of bioavailable DOM export was observed that correlated with discharge, vegetation, river morphology and water residence time. The chemical composition of bioavailable DOM was different among rivers reflecting unique characteristics of Arctic river watersheds. …


Mass Coral Mortality Under Local Amplification Of 2 °C Ocean Warming, Thomas M. Decarlo, Anne L. Cohen, George T. F. Wong, Kristen A. Davis, Pat Lohman, Keryea Soong Mar 2017

Mass Coral Mortality Under Local Amplification Of 2 °C Ocean Warming, Thomas M. Decarlo, Anne L. Cohen, George T. F. Wong, Kristen A. Davis, Pat Lohman, Keryea Soong

OES Faculty Publications

A 2 °C increase in global temperature above pre-industrial levels is considered a reasonable target for avoiding the most devastating impacts of anthropogenic climate change. In June 2015, sea surface temperature (SST) of the South China Sea (SCS) increased by 2 °C in response to the developing Pacific El Nino. On its own, this moderate, short-lived warming was unlikely to cause widespread damage to coral reefs in the region, and the coral reef "Bleaching Alert" alarm was not raised. However, on Dongsha Atoll, in the northern SCS, unusually weak winds created low-flow conditions that amplified the 2 °C basin-scale …


Twenty-First Century Climate Change And Submerged Aquatic Vegetation In A Temperate Estuary: The Case Of Chesapeake Bay, Thomas M. Arnold, Richard C. Zimmerman, Katharina A.M. Engelhardt, J. Court Stevenson Jan 2017

Twenty-First Century Climate Change And Submerged Aquatic Vegetation In A Temperate Estuary: The Case Of Chesapeake Bay, Thomas M. Arnold, Richard C. Zimmerman, Katharina A.M. Engelhardt, J. Court Stevenson

OES Faculty Publications

Introduction: The Chesapeake Bay was once renowned for expansive meadows of submerged aquatic vegetation (SAV). However, only 10% of the original meadows survive. Future restoration effortswill be complicated by accelerating climate change, including physiological stressors such as a predicted mean temperature increase of 2-6°C and a 50-160% increase in CO2 concentrations.

Outcomes: As the Chesapeake Bay begins to exhibit characteristics of a subtropical estuary, summer heat waves will become more frequent and severe. Warming alone would eventually eliminate eelgrass (Zostera marina) from the region. It will favor native heat-tolerant species such as widgeon grass (Ruppia maritima) while facilitating colonization by …


Upper Water Structure And Mixed Layer Depth In Tropical Waters: The Seats Station In The Northern South China Sea, Jen-Hua Tai, George T. F. Wong, Xiaoju Pan Jan 2017

Upper Water Structure And Mixed Layer Depth In Tropical Waters: The Seats Station In The Northern South China Sea, Jen-Hua Tai, George T. F. Wong, Xiaoju Pan

OES Faculty Publications

The variability of the upper water hydrographic structure, the efficacy of the different schemes for estimating the mixed layer depth (MLD), the inter-comparability estimation of the MLDs and diurnal and intra-annual MLD climatology in the tropical waters in the northern South China Sea were accessed in 702 depth-profiles of potential temperature (θ) and salinity collected in 64 cruises between 17.5 and 18.5°N and 115.3 and 116.3°E from 1997 to 2013. The hydrographic structure may be subdivided into three principal types: the classical type, with quasi-isopycnal surface mixed layer followed by an abrupt increase in the depth-gradient in θ and potential …


Spatial Patterns Of Sea Level Variability Associated With Natural Internal Climate Modes, Weiqing Han, Gerald A. Meehl, Detlef Stammer, Aixue Hu, Benjamin Hamlington, Jessica Kenigson, Hindumathi Palanisamy, Philip Thompson Jan 2017

Spatial Patterns Of Sea Level Variability Associated With Natural Internal Climate Modes, Weiqing Han, Gerald A. Meehl, Detlef Stammer, Aixue Hu, Benjamin Hamlington, Jessica Kenigson, Hindumathi Palanisamy, Philip Thompson

OES Faculty Publications

Sea level rise (SLR) can exert significant stress on highly populated coastal societies and low-lying island countries around the world. Because of this, there is huge societal demand for improved decadal predictions and future projections of SLR, particularly on a local scale along coastlines. Regionally, sea level variations can deviate considerably from the global mean due to various geophysical processes. These include changes of ocean circulations, which partially can be attributed to natural, internal modes of variability in the complex Earth's climate system. Anthropogenic influence may also contribute to regional sea level variations. Separating the effects of natural climate modes …


Understanding Ocean Acidification Impacts On Organismal To Ecological Scales, Andreas J. Andersson, David I. Kline, Peter J. Edmunds, Stephen D. Archer, Nina Bednarsek, Robert C. Carpenter, Meg Chadsey, Philip Goldstein, Andrea G. Grottoli, Thomas P. Hurst, Andrew L. King, Janet E. Kübler, Ilsa B. Kuffner, Katherine R.M. Mackey, Bruce A. Menge, Adina Paytan, Ulf Riebesell, Astrid Schnetzer, Mark E. Warner, Richard C. Zimmerman Jan 2015

Understanding Ocean Acidification Impacts On Organismal To Ecological Scales, Andreas J. Andersson, David I. Kline, Peter J. Edmunds, Stephen D. Archer, Nina Bednarsek, Robert C. Carpenter, Meg Chadsey, Philip Goldstein, Andrea G. Grottoli, Thomas P. Hurst, Andrew L. King, Janet E. Kübler, Ilsa B. Kuffner, Katherine R.M. Mackey, Bruce A. Menge, Adina Paytan, Ulf Riebesell, Astrid Schnetzer, Mark E. Warner, Richard C. Zimmerman

OES Faculty Publications

Ocean acidification (OA) research seeks to understand how marine ecosystems and global elemental cycles will respond to changes in seawater carbonate chemistry in combination with other environmental perturbations such as warming, eutrophication, and deoxygenation. Here, we discuss the effectiveness and limitations of current research approaches used to address this goal. A diverse combination of approaches is essential to decipher the consequences of OA to marine organisms, communities, and ecosystems. Consequently, the benefits and limitations of each approach must be considered carefully. Major research challenges involve experimentally addressing the effects of OA in the context of large natural variability in seawater …


Living On The Margin In The Anthropocene: Engagement Arenas For Sustainability Research And Action At The Ocean-Land Interface, B. C. Glavovic, K. Limburg, K-K. Liu, K-C. Emeis, H. Thomas, H. Kremer, B. Avril, J. Zhang, M. R. Mulholland, M. Glaser, D. P. Swaney Jan 2015

Living On The Margin In The Anthropocene: Engagement Arenas For Sustainability Research And Action At The Ocean-Land Interface, B. C. Glavovic, K. Limburg, K-K. Liu, K-C. Emeis, H. Thomas, H. Kremer, B. Avril, J. Zhang, M. R. Mulholland, M. Glaser, D. P. Swaney

OES Faculty Publications

The advent of the Anthropocene underscores the need to develop and implement transformative governance strategies that safeguard the Earth's life-support systems, most critically at the ocean-land interface - the Margin. The seaward realm of the Margin is the new frontier for resource exploitation and colonization to meet the needs of coastal nations and humanity overall. Here, we spotlight the pivotal role of the Margin for planetary resilience and sustainability, highlight priority issues, and outline a research strategy which aims to: (a) better understand Margin social-ecological systems; (b) guide sustainable development of Margin resources; (c) design governance regimes to reverse unsustainable …


Can We Predict The Future: Juvenile Finfish And Their Seagrass Nurseries In The Chesapeake Bay, Cynthia M. Jones Jan 2014

Can We Predict The Future: Juvenile Finfish And Their Seagrass Nurseries In The Chesapeake Bay, Cynthia M. Jones

OES Faculty Publications

The importance of estuarine seagrass beds as nurseries for juvenile fish has become a universal paradigm, especially for estuaries that are as important as the Chesapeake Bay. Yet, scientific tests of this hypothesis were equivocal depending on species, location, and metrics. Moreover, seagrasses themselves are under threat and one-third of seagrasses have disappeared worldwide with 65 of their losses occurring in estuaries. Although there have been extensive studies of seagrasses in the Chesapeake Bay, surprisingly few studies have quantified the relationship between seagrass as nurseries for finfish in the Bay. Of the few studies that have directly evaluated the use …


Marine Phytoplankton Temperature Versus Growth Responses From Polar To Tropical Waters- Outcome Of A Scientific Community-Wide Study, Philip W. Boyd, Tatiana A. Rynearson, Evelyn A. Armstrong, Feixue Fu, Kendra Hayashi, Zhangxi Hu, David A. Hutchins, Elena Litchman, Margaret R. Mulholland, Uta Passow, Robert F. Stzepek, Kerry A. Whittaker, Elizabeth Yu, Mridul K. Thomas May 2013

Marine Phytoplankton Temperature Versus Growth Responses From Polar To Tropical Waters- Outcome Of A Scientific Community-Wide Study, Philip W. Boyd, Tatiana A. Rynearson, Evelyn A. Armstrong, Feixue Fu, Kendra Hayashi, Zhangxi Hu, David A. Hutchins, Elena Litchman, Margaret R. Mulholland, Uta Passow, Robert F. Stzepek, Kerry A. Whittaker, Elizabeth Yu, Mridul K. Thomas

OES Faculty Publications

“It takes a village to finish (marine) science these days”

Paraphrased from Curtis Huttenhower (the Human Microbiome project)

The rapidity and complexity of climate change and its potential effects on ocean biota are challenging how ocean scientists conduct research. One way in which we can begin to better tackle these challenges is to conduct community-wide scientific studies. This study provides physiological datasets fundamental to understanding functional responses of phytoplankton growth rates to temperature. While physiological experiments are not new, our experiments were conducted in many laboratories using agreed upon protocols and 25 strains of eukaryotic and prokaryotic phytoplankton …


The Ross Sea: In A Sea Of Change, Walker O. Smith, Peter N. Sedwick, Kevin R. Arrigo, David G. Ainley, Alejandro H. Orsi Sep 2012

The Ross Sea: In A Sea Of Change, Walker O. Smith, Peter N. Sedwick, Kevin R. Arrigo, David G. Ainley, Alejandro H. Orsi

OES Faculty Publications

The Ross Sea, the most productive region in the Antarctic, reaches farther south than any body of water in the world. While its food web is relatively intact, its oceanography, biogeochemistry, and sea ice coverage have been changing dramatically, and likely will continue to do so in the future. Sea ice cover and persistence have been increasing, in contrast to the Amundsen-Bellingshausen sector, which has resulted in reduced open water duration for its biota. Models predict that as the ozone hole recovers, ice cover will begin to diminish. Currents on the continental shelf will likely change in the coming century, …


An Introduction To Ecology Of Infectious Diseases - Oysters And Estuaries, Eileen E. Hofmann, Susan E. Ford Jan 2012

An Introduction To Ecology Of Infectious Diseases - Oysters And Estuaries, Eileen E. Hofmann, Susan E. Ford

OES Faculty Publications

Infectious diseases are recognized as an important factor regulating marine ecosystems (Harvell et al., 1999, 2002, 2004; Porter et al., 2001; McCallum et al., 2004; Ward and Lafferty, 2004; Stewart et al., 2008; Bienfang et al., 2011). Many of the organisms affected by marine diseases have important ecological roles in estuarine and coastal environments and some are also commercially important. Outbreaks of infectious diseases in these environments, referred to as epizootics, can produce significant population declines and extinctions, both of which threaten biodiversity, food web interactions, and ecosystem productivity (Harvell et al., 2002, 2004).


A Robust, Multisite Holocene History Of Drift Ice Off Northern Iceland: Implications For North Atlantic Climate, John T. Andrews, Dennis A. Darby, Dennis Eberle, Anne E. Jennings, Matthias Moros, Astrid Ogilvie Jan 2009

A Robust, Multisite Holocene History Of Drift Ice Off Northern Iceland: Implications For North Atlantic Climate, John T. Andrews, Dennis A. Darby, Dennis Eberle, Anne E. Jennings, Matthias Moros, Astrid Ogilvie

OES Faculty Publications

An important indicator of Holocene climate change is provided by evidence for variations in the extent of drift ice. A proxy for drift ice in Iceland waters is provided by the presence of quartz. Quantitative xray diffraction analysis of the < 2 mm sediment fraction was undertaken on 16 cores from around Iceland. The quartz weight (wt.)% estimates from each core were integrated into 250-yr intervals between −0.05 and 11.7 cal. ka BP. Median quartz wt.% varied between 0.2 and 3.4 and maximum values ranged between 2.8 and 11.8 wt.%. High values were attained in the early Holocene and minimum values were reached 6–7 cal. ka BP. Quartz wt.% then rose steadily during the late Holocene. Our data exhibit no correlation with counts on haematite-stained quartz (HSQ) grains from VM129-191 west of Ireland casting doubt on the ice-transport origin. A pilot study on the provenance of Fe oxide grains in two cores that cover the last 1.3 and 6.1 cal. ka BP indicated a large fraction of the grains between 1 and 6 cal. ka BP were from either Icelandic or presently unsampled sources. However, there was a dramatic increase in Canadian and Russian sources from the Arctic Ocean ~1 cal. ka BP. These data may indicate the beginning of an Arctic Oscillation-like climate mode.


Co2 Sensitivity Of Southern Ocean Phytoplankton, Philippe D. Tortell, Christopher D. Payne, Yingyu Li, Scarlett Trimborn, Bjorn Rost, Walker O. Smith, Christina Riesselman, Robert B. Dunbar, Peter Sedwick, Giacomo R. Ditullio Jan 2008

Co2 Sensitivity Of Southern Ocean Phytoplankton, Philippe D. Tortell, Christopher D. Payne, Yingyu Li, Scarlett Trimborn, Bjorn Rost, Walker O. Smith, Christina Riesselman, Robert B. Dunbar, Peter Sedwick, Giacomo R. Ditullio

OES Faculty Publications

The Southern Ocean exerts a strong impact on marine biogeochemical cycles and global air-sea CO2 fluxes. Over the coming century, large increases in surface ocean CO2 levels, combined with increased upper water column temps. and stratification, are expected to diminish Southern Ocean CO2 uptake. These effects could be significantly modulated by concomitant CO2-dependent changes in the region's biol. carbon pump. Here we show that CO2 concentrations affect the physiology, growth and species composition. of phytoplankton assemblages in the Ross Sea, Antarctica. Field results from in situ sampling and ship-board incubation experiments demonstrate that inorganic …


Response Of Eelgrass Zostera Marina To Co2 Enrichment: Possible Impacts Of Climate Change And Potential For Remediation Of Coastal Habitats, Sherry L. Palacios, Richard C. Zimmerman Jan 2007

Response Of Eelgrass Zostera Marina To Co2 Enrichment: Possible Impacts Of Climate Change And Potential For Remediation Of Coastal Habitats, Sherry L. Palacios, Richard C. Zimmerman

OES Faculty Publications

Projected increases in dissolved aqueous concentrations of carbon dioxide [CO2(aq)] may have significant impacts on photosynthesis Of CO2-limited organisms such as seagrasses. Short-term CO2(aq) enrichment increases photosynthetic rates and reduces light requirements for growth and survival of individual eelgrass Zostera marina L. shoots growing in the laboratory under artificial light regimes for at least 45 d. This study examined the effects of long-term CO2(aq) enrichment on the performance of eelgrass growing under natural light-replete (33% surface irradiance) and light-limited (5% surface irradiance) conditions for a period of 1 yr. Eelgrass shoots were grown at …


Past Glacial And Interglacial Conditions In The Arctic Ocean And Marginal Seas - A Review, Dennis A. Darby, Leonid Polyak, Henning A. Bauch Jan 2006

Past Glacial And Interglacial Conditions In The Arctic Ocean And Marginal Seas - A Review, Dennis A. Darby, Leonid Polyak, Henning A. Bauch

OES Faculty Publications

Past changes in the Arctic Ocean and its marginal seas have been profound, even during the last 10,000 years. Understanding these changes, such as those occurring during the transition from glacial to interglacial climates, are important for research on modern processes, because this knowledge provides a framework and unique perspective in which to view the modern physical and biological processes. This paper discusses our current understanding of past environmental change and processes relative to those currently in progress. Special emphasis is placed on the most recent transition from a glacial state to the modern interglacial conditions.


Hydrographic And Biological Changes In The Taiwan Strait During The 1997-1998 El Niño Winter, S. Shang, C. Zhang, H. Hong, Q. Liu, G. T. F. Wong, C. Hu, B. Huang Jan 2005

Hydrographic And Biological Changes In The Taiwan Strait During The 1997-1998 El Niño Winter, S. Shang, C. Zhang, H. Hong, Q. Liu, G. T. F. Wong, C. Hu, B. Huang

OES Faculty Publications

During the 1997–1998 El Niño event, the average sea surface temperature (SST) in the Taiwan Strait (TWS) in the winter was ~1.4°C higher than that of the winter climatological mean. The areal ratio of the warm water (≥2°C above the regional mean) to the cold water (≥2°C below the regional mean) in the TWS increased by 25% while the area of the eutrophic water (chlorophyll a >1 mg m-3) was halved. Field observations also indicate that the mixed layer in the TWS became more nutrient-poor during this winter. These observations are consistent with a diminished advection of the …


Iron In The Sargasso Sea (Bermuda Atlantic Time-Series Study Region) During Summer: Eolian Imprint, Spatiotemporal Variability, And Ecological Implications, Peter N. Sedwick, T. M. Church, A. R. Bowie, C. M. Marsay, S. J. Ussher, K. M. Achilles, P. J. Lethaby, R. J. Johnson, M. M. Sarin, D. J. Mcgillicuddy Jan 2005

Iron In The Sargasso Sea (Bermuda Atlantic Time-Series Study Region) During Summer: Eolian Imprint, Spatiotemporal Variability, And Ecological Implications, Peter N. Sedwick, T. M. Church, A. R. Bowie, C. M. Marsay, S. J. Ussher, K. M. Achilles, P. J. Lethaby, R. J. Johnson, M. M. Sarin, D. J. Mcgillicuddy

OES Faculty Publications

We report iron measurements for water column and aerosol samples collected in the Sargasso Sea during July-August 2003 (summer 2003) and April-May 2004 (spring 2004). Our data reveal a large seasonal change in the dissolved iron (dFe) concentration of surface waters in the Bermuda Atlantic Time-series Study region, from ∼1-2nM in summer 2003, when aerosol iron concentrations were high (mean 10 nmol/m-3), to ∼0.1-0.2nM in spring 2004, when aerosol iron concentrations were low (mean 0.64 nmol/m-3). During summer 2003, we observed an increase of ∼0.6nM in surface water dFe concentrations over 13 days, presumably due to …


A Holocene Record Of Changing Arctic Ocean Ice Drift Analogous To The Effects Of The Arctic Oscillation, Dennis A. Darby, Jens F. Bischof Jan 2004

A Holocene Record Of Changing Arctic Ocean Ice Drift Analogous To The Effects Of The Arctic Oscillation, Dennis A. Darby, Jens F. Bischof

OES Faculty Publications

The Arctic Oscillation (AO) controls the configuration of the Transpolar Drift (TPD). If thicker ice from the Beaufort Gyre were exported, the volume of fresh water/sea ice in the Nordic seas would significantly increase, decreasing the formation of North Atlantic deep water. This would cool large parts of the Northern Hemisphere and affect global climate. Therefore, in order to understand how the global climate system functions, it is imperative to know how the TPD changed over the last millennium or more. The provenance of grains in a sediment core located near the confluence of the TPD and the Beaufort Gyre …


Introduction To Special Section: Saz Project, T. W. Trull, Peter N. Sedwick, F. B. Griffiths, S. R. Rintoul Jan 2001

Introduction To Special Section: Saz Project, T. W. Trull, Peter N. Sedwick, F. B. Griffiths, S. R. Rintoul

OES Faculty Publications

Oceanographic processes in the subantarctic region contribute crucially to the phys. and biogeochemical aspects of the global climate system. To explore and quantify these contributions, the Antarctic Cooperative Research Center organized the SAZ Project, a multidisciplinary, multiship study carried out south of Australia in the austral summer of 1997-1998. We present an overview of the SAZ Project and some of its major results.


Effects Of El Nino On Local Hydrography And Growth Of The Giant Kelp, Macrocystis Pyrifera, At Santa Catalina Island, California, Richard C. Zimmerman, Deborah L. Robertson Jan 1985

Effects Of El Nino On Local Hydrography And Growth Of The Giant Kelp, Macrocystis Pyrifera, At Santa Catalina Island, California, Richard C. Zimmerman, Deborah L. Robertson

OES Faculty Publications

Deepened isotherms associated with El Niño resulted in severe nutrient limitation and very low kelp productivity during the last half of 1983. Frond growth rates were so low that terminal blades formed before reaching the surface, eliminating the canopy. Frond initiation rates were also extremely low, resulting in significant reductions in mean plant size. Plants growing above 10m were more severely affected than plants at 20m. Nutrient pulses associated with internal waves are thus critical for survival of Macrocystis pyrifera in nutritionally marginal habitats in Southern California.