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Articles 901 - 930 of 2279

Full-Text Articles in Life Sciences

Dispersant Enhances Hydrocarbon Degradation And Alters The Structure Of Metabolically Active Microbial Communities In Shallow Seawater From The Northeastern Gulf Of Mexico, Lena Chu, Elisa Mercando, Roger C. Prince, Isabel C. Romero, David Hollander Mar 2018

Dispersant Enhances Hydrocarbon Degradation And Alters The Structure Of Metabolically Active Microbial Communities In Shallow Seawater From The Northeastern Gulf Of Mexico, Lena Chu, Elisa Mercando, Roger C. Prince, Isabel C. Romero, David Hollander

C-IMAGE data

The seawater samples were collected from Pensacola Beach, FL in June and August, 2016. The seawater was incubated with low concentration of oil (2ppm) with or without dispersant. Oil analysis and sequencing data were generated.


Avoiding Timescale Bias In Assessments Of Coastal Wetland Vertical Change, Joshua L. Breithaupt, Joseph M. Smoak, Robert H. Byrne, Matthew N. Waters, Ryan P. Moyer, Christian J. Sanders Mar 2018

Avoiding Timescale Bias In Assessments Of Coastal Wetland Vertical Change, Joshua L. Breithaupt, Joseph M. Smoak, Robert H. Byrne, Matthew N. Waters, Ryan P. Moyer, Christian J. Sanders

Marine Science Faculty Publications

There is concern that accelerating sea‐level rise will exceed the vertical growth capacity of coastal‐wetland substrates in many regions by the end of this century. Vertical vulnerability estimates rely on measurements of accretion and/or surface‐elevation‐change derived from soil cores and/or surface elevation tables (SETs). To date there has not been a broad examination of whether the multiple timescales represented by the processes of accretion and elevation change are equally well‐suited for quantifying the trajectories of wetland vertical change in coming decades and centuries. To examine the potential for timescale bias in assessments of vertical change, we compared rates of accretion …


Ocean Futures Under Ocean Acidification, Marine Protection, And Changing Fishing Pressures Explored Using A Worldwide Suite Of Ecosystem Models, Erik Olsen, Isaac C. Kaplan, Cameron Ainsworth, Gavin Fay, Sarah Gaichas, Robert Gamble, Raphael Girardin, Cecilie H. Eide, Thomas F. Ihde Mar 2018

Ocean Futures Under Ocean Acidification, Marine Protection, And Changing Fishing Pressures Explored Using A Worldwide Suite Of Ecosystem Models, Erik Olsen, Isaac C. Kaplan, Cameron Ainsworth, Gavin Fay, Sarah Gaichas, Robert Gamble, Raphael Girardin, Cecilie H. Eide, Thomas F. Ihde

Marine Science Faculty Publications

Ecosystem-based management (EBM) of the ocean considers all impacts on and uses of marine and coastal systems. In recent years, there has been a heightened interest in EBM tools that allow testing of alternative management options and help identify tradeoffs among human uses. End-to-end ecosystem modeling frameworks that consider a wide range of management options are a means to provide integrated solutions to the complex ocean management problems encountered in EBM. Here, we leverage the global advances in ecosystem modeling to explore common opportunities and challenges for ecosystem-based management, including changes in ocean acidification, spatial management, and fishing pressure across …


Evaluation Of Diet Matrix Uncertainty For The Atlantis Model, Cameron Ainsworth Mar 2018

Evaluation Of Diet Matrix Uncertainty For The Atlantis Model, Cameron Ainsworth

C-IMAGE data

We conducted 1000 Atlantis simulations, using permutated diet matrices created by drawing from a beta distribution that represented uncertainty in predator diet. We also employed a statistical emulator which simulates the production of many more Atlantis runs than could be achieved through numerical simulation. This dataset includes 3 products: statistical emulator output, diet matrices, and Atlantis simulations. These are each contained in their own zip file.


Do Host‐Associated Gut Microbiota Mediate The Effect Of An Herbicide On Disease Risk In Frogs?, Sarah A. Knutie, Caitlin R. Gabor, Kevin D. Kohl, Jason R. Rohr Mar 2018

Do Host‐Associated Gut Microbiota Mediate The Effect Of An Herbicide On Disease Risk In Frogs?, Sarah A. Knutie, Caitlin R. Gabor, Kevin D. Kohl, Jason R. Rohr

Integrative Biology Faculty and Staff Publications

  1. Environmental stressors, such as pollutants, can increase disease risk in wildlife. For example, the herbicide atrazine affects host defences (e.g. resistance and tolerance) of the amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd), but the mechanisms for these associations are not entirely clear. Given that pollutants can alter the gut microbiota of hosts, which in turn can affect their health and immune systems, one potential mechanism by which pollutants could increase infection risk is by influencing host‐associated microbiota.
  2. Here, we test whether early‐life exposure to the estimated environmental concentration (EEC; 200 μg/L) of atrazine affects the gut bacterial composition of …


Circulating Pander Concentration Is Associated With Increased Hba1c And Fasting Blood Glucose In Type 2 Diabetic Subjects, Catherine B. Marelia, Melanie N. Kuehl, Tiffany A. Shemwell, Amy C. Alman, Brant R. Burkhardt Mar 2018

Circulating Pander Concentration Is Associated With Increased Hba1c And Fasting Blood Glucose In Type 2 Diabetic Subjects, Catherine B. Marelia, Melanie N. Kuehl, Tiffany A. Shemwell, Amy C. Alman, Brant R. Burkhardt

Molecular Biosciences Faculty Publications

Aim: PANcreatic-DERived factor (PANDER, FAM3B) is a novel hormone that regulates glucose levels via interaction with both the endocrine pancreas and liver. Prior studies examining PANDER were primarily conducted in murine models or in vitro but little is known regarding the circulating concentration of PANDER in humans, especially with regard to the association of type 2 diabetes (T2D) or overall glycemic regulation. To address this limitation, we performed a cross-sectional analysis of circulating serum PANDER concentration in association with other hormones that serve as either markers of insulin resistance (insulin and adiponectin) or to metabolic parameters of glycemic control such …


Deciphering The State Of The Late Miocene To Early Pliocene Equatorial Pacific, A. J. Drury, G. P. Lee, W. R. Gray, M. Lyle, T. Westerhold, Amelia E. Shevenell, C. M. John Mar 2018

Deciphering The State Of The Late Miocene To Early Pliocene Equatorial Pacific, A. J. Drury, G. P. Lee, W. R. Gray, M. Lyle, T. Westerhold, Amelia E. Shevenell, C. M. John

Marine Science Faculty Publications

The late Miocene‐early Pliocene was a time of global cooling and the development of modern meridional thermal gradients. Equatorial Pacific sea surface conditions potentially played an important role in this global climate transition, but their evolution is poorly understood. Here we present the first continuous late Miocene‐early Pliocene (8.0–4.4 Ma) planktic foraminiferal stable isotope records from eastern equatorial Pacific Integrated Ocean Drilling Program Site U1338, with a new astrochronology spanning 8.0–3.5 Ma. Mg/Ca analyses on surface dwelling foraminifera Trilobatus sacculifer from carefully selected samples suggest that mean sea surface temperatures (SSTs) are ~27.8 ± 1.1°C (1σ) between 6.4 and 5.5 …


The Biogeochemical Cycling Of Iron, Copper, Nickel, Cadmium, Manganese, Cobalt, Lead, And Scandium In A California Current Experimental Study, Travis Mellett, Matthew T. Brown, P. Dreux Chappell, Carolyn Duckham Carolyn Duckham, Jessica N. Fitzsimmons, Claire P. Till, Robert M. Sherrell, Maria T. Maldonado, Kristen N. Buck Mar 2018

The Biogeochemical Cycling Of Iron, Copper, Nickel, Cadmium, Manganese, Cobalt, Lead, And Scandium In A California Current Experimental Study, Travis Mellett, Matthew T. Brown, P. Dreux Chappell, Carolyn Duckham Carolyn Duckham, Jessica N. Fitzsimmons, Claire P. Till, Robert M. Sherrell, Maria T. Maldonado, Kristen N. Buck

Marine Science Faculty Publications

A 3‐day shipboard incubation experiment was conducted in the California Current System in July 2014 to investigate the cycling of iron (Fe), copper (Cu), nickel (Ni), cadmium (Cd), manganese (Mn), cobalt (Co), lead (Pb), and scandium (Sc) under a range of light and particle conditions. Filtered (< 0.2 μm) and unfiltered treatments were incubated under the following light conditions: Dark, light (“UV”), and light without the ultraviolet (UV) wavelengths (“noUV”). The experiment was sampled for carbon and Fe uptake rates, dissolved trace metal concentrations (Fe, Cu, Ni, Cd, Mn, Co, Pb, Sc), Fe and Cu speciation, size‐fractionated concentrations of Cd and Fe, and diatom community composition from DNA sequencing. Exposure to UV light increased phytoplankton Fe uptake in the first 24 h of the incubation relative to the noUV treatment, suggesting that a fraction of the ambient ligand‐bound Fe was photoreactive. Fe‐binding organic ligand production was observed in the unfiltered light treatments in association with increasing chlorophyll a, and evidence for Cu‐binding ligand production in these treatments was also observed. Biological uptake of Cd and Co was observed along with scavenging of dissolved Pb. Manganese appeared to be rapidly oxidized by Mn‐oxidizing bacteria with concomitant drawdown of dissolved Ni. Scandium displayed similar trends to Fe, reinforcing the limited observations …


Angiostrongylus Cantonensis: Epidemiologic Review, Location-Specific Habitat Modelling, And Surveillance In Hillsborough County, Florida, U.S.A., Brad Christian Perich Mar 2018

Angiostrongylus Cantonensis: Epidemiologic Review, Location-Specific Habitat Modelling, And Surveillance In Hillsborough County, Florida, U.S.A., Brad Christian Perich

USF Tampa Graduate Theses and Dissertations

Angiostrongylus cantonensis is a parasitic nematode endemic to tropical and subtropical regions and is the leading cause of human eosinophilic meningitis. The parasite is commonly known as rat lungworm because the primary host in its lifecycle is the rat. A clinical overview of rat lungworm infection is presented, followed by a literature review of rat lungworm epidemiology, risk factors, and surveillance projects. Data collected from previous snail surveys in Florida was considered alongside elevation, population per square kilometer, median household income by zip code territory, and normalized difference vegetation index specific to the geographic coordinates from which the snail samples …


Trace Metals And Minor Elements In Southern Gulf Of Mexico Sediments Following The Ixtoc Marine Oil Blow Out Event, 2015, David W. Hastings, Thomas Bartlett Feb 2018

Trace Metals And Minor Elements In Southern Gulf Of Mexico Sediments Following The Ixtoc Marine Oil Blow Out Event, 2015, David W. Hastings, Thomas Bartlett

C-IMAGE data

Our objective is to compare the impact of two marine oil well blowouts on surface sediments in the Gulf of Mexico: the recent 2010 DWH blowout in the Northern Gulf with the Ixtoc blowout in 1979/80 in the Southern Gulf. A suite of trace and minor elements (V, Cr, Mn, Fe, Co, Ni, Cu, Sr, Cd, Mo, Ba, Re, and U) some of which are sensitive to changes in sedimentary redox conditions, was analyzed in bulk surface sediments; that data is presented here. Sediment cores were collected in the SE GoM on a research cruise on the R/V Justo Sierra …


Interspecific Interactions May Influence Reef Fish Management Strategies In The Gulf Of Mexico, Michelle D. Masi, Cameron H. Ainsworth, I. C. Kaplan, M. J. Schirripa Feb 2018

Interspecific Interactions May Influence Reef Fish Management Strategies In The Gulf Of Mexico, Michelle D. Masi, Cameron H. Ainsworth, I. C. Kaplan, M. J. Schirripa

Marine Science Faculty Publications

This study highlights the importance of interspecific interactions among marine organisms and the effect that these trophic interactions have on the development of effective, adaptive management strategies for reef fishes in the Gulf of Mexico. To represent the spatially and temporally constrained, interspecific interactions among reef fishes we employ Atlantis (a spatially explicit, biogeochemical ecosystem model) as our simulation tool. Within Atlantis, we evaluate the performance of a two‐point harvest control rule (HCR) that adaptively increases fishing mortality linearly between upper and lower biomass thresholds based on the available biomass of the stocks. This example demonstrated the use of a …


Climate-Change–Driven Accelerated Sea-Level Rise Detected In The Altimeter Era, R. S. Nerem, B. D. Beckley, J. T. Fasullo, B. D. Hamlinigton, D. Masters, Gary T. Mitchum Feb 2018

Climate-Change–Driven Accelerated Sea-Level Rise Detected In The Altimeter Era, R. S. Nerem, B. D. Beckley, J. T. Fasullo, B. D. Hamlinigton, D. Masters, Gary T. Mitchum

Marine Science Faculty Publications

Using a 25-y time series of precision satellite altimeter data from TOPEX/Poseidon, Jason-1, Jason-2, and Jason-3, we estimate the climate-change–driven acceleration of global mean sea level over the last 25 y to be 0.084 ± 0.025 mm/y2. Coupled with the average climate-change–driven rate of sea level rise over these same 25 y of 2.9 mm/y, simple extrapolation of the quadratic implies global mean sea level could rise 65 ± 12 cm by 2100 compared with 2005, roughly in agreement with the Intergovernmental Panel on Climate Change (IPCC) 5th Assessment Report (AR5) model projections.


Agrochemicals Increase Risk Of Human Schistosomiasis By Supporting Higher Densities Of Intermediate Hosts, Neal T. Halstead, Christopher M. Hoover, Arathi Arakala, David J. Civitello, Guilio A. De Leo, Manoj Gambhir, Steve A. Johnson, Nicolas Jouanard, Kristin A. Loerns, Karena Nguyen, Jason R. Rohr Feb 2018

Agrochemicals Increase Risk Of Human Schistosomiasis By Supporting Higher Densities Of Intermediate Hosts, Neal T. Halstead, Christopher M. Hoover, Arathi Arakala, David J. Civitello, Guilio A. De Leo, Manoj Gambhir, Steve A. Johnson, Nicolas Jouanard, Kristin A. Loerns, Karena Nguyen, Jason R. Rohr

Integrative Biology Faculty and Staff Publications

Schistosomiasis is a snail-borne parasitic disease that ranks among the most important water-based diseases of humans in developing countries. Increased prevalence and spread of human schistosomiasis to non-endemic areas has been consistently linked with water resource management related to agricultural expansion. However, the role of agrochemical pollution in human schistosome transmission remains unexplored, despite strong evidence of agrochemicals increasing snail-borne diseases of wildlife and a projected 2- to 5-fold increase in global agrochemical use by 2050. Using a field mesocosm experiment, we show that environmentally relevant concentrations of fertilizer, a herbicide, and an insecticide, individually and as mixtures, increase densities …


Impacts Of The Deepwater Horizon Oil Spill Evaluated Using An End-To-End Ecosystem Model, Cameron Ainsworth, Claire B. Paris-Limouzy, Natalie Perlin, Lindsey N. Dornberger, William F. Patterson Iii, Emily Chancellor, Steven Murawski, David J. Hollander, Kendra L. Daly, Isabel Romero, Felicia Coleman, Holly Perryman Jan 2018

Impacts Of The Deepwater Horizon Oil Spill Evaluated Using An End-To-End Ecosystem Model, Cameron Ainsworth, Claire B. Paris-Limouzy, Natalie Perlin, Lindsey N. Dornberger, William F. Patterson Iii, Emily Chancellor, Steven Murawski, David J. Hollander, Kendra L. Daly, Isabel Romero, Felicia Coleman, Holly Perryman

C-IMAGE Publications

We use a spatially explicit biogeochemical end-to-end ecosystem model, Atlantis, to simulate impacts from the Deepwater Horizon oil spill and subsequent recovery of fish guilds. Dose-response relationships with expected oil concentrations were utilized to estimate the impact on fish growth and mortality rates. We also examine the effects of fisheries closures and impacts on recruitment. We validate predictions of the model by comparing population trends and age structure before and after the oil spill with fisheries independent data. The model suggests that recruitment effects and fishery closures had little influence on biomass dynamics. However, at the assumed level of oil …


Novel Role Of Histone Deacetylase 11 (Hdac11) In Regulating Normal And Malignant Hematopoiesis, Jie Chen Jan 2018

Novel Role Of Histone Deacetylase 11 (Hdac11) In Regulating Normal And Malignant Hematopoiesis, Jie Chen

USF Tampa Graduate Theses and Dissertations

During hematopoiesis, multilineage progenitor cells and the precursors are committed to individual hematopoietic lineages. In normal myelopoiesis, the immature myeloid cells (IMCs) differentiate into macrophages, neutrophils or dendritic cells. However, under tumor burden, these IMCs differentiate into myeloid derived suppressor cells (MDSCs) result in an up-regulation of immune suppressive factors and pro-tumor effect. The development of normal or malignant is tightly controlled by endogenous signals such as transcription factors and epigenetic regulations. HDAC11 is the newest identified members of the histone deacetylase (HDAC) family. Previous study in our group had identified HDAC11 as a negative regulator of interleukin 10 (IL-10) …


Characterization Of The Transcriptional Elongation Factor Ell3 In B Cells And Its Role In B-Cell Lymphoma Proliferation And Survival, Lou-Ella M.M. Alexander Jan 2018

Characterization Of The Transcriptional Elongation Factor Ell3 In B Cells And Its Role In B-Cell Lymphoma Proliferation And Survival, Lou-Ella M.M. Alexander

USF Tampa Graduate Theses and Dissertations

The studies presented in this dissertation establish the dynamics of Eleven nineteen Lysine-rich leukemia (ELL) family of elongation factors during B cell differentiation and provide a description of ELL3 function in B cells.

The transition from a mature naïve B cells into an activated B cell is dependent on a large increase in transcriptional output, which is followed by focused expression on secreted immunoglobulin upon terminal differentiation into plasma cell. While ELL family members have previously been implicated in alternative splicing at the immunoglobulin heavy chain locus in plasma cells, their presence and function prior to differentiation is currently not …


Updated Methods For Global Locally Interpolated Estimation Of Alkalinity, Ph, And Nitrate, B. R. Carter, R. A. Feely, N. L. Williams, A. G. Dickson, M. B. Fong, Y. Takeshita Jan 2018

Updated Methods For Global Locally Interpolated Estimation Of Alkalinity, Ph, And Nitrate, B. R. Carter, R. A. Feely, N. L. Williams, A. G. Dickson, M. B. Fong, Y. Takeshita

Marine Science Faculty Publications

We have taken advantage of the release of version 2 of the Global Data Analysis Project data product (Olsen et al. 2016) to refine the locally interpolated alkalinity regression (LIAR) code for global estimation of total titration alkalinity of seawater (AT), and to extend the method to also produce estimates of nitrate (N) and in situ pH (total scale). The updated MATLAB software and methods are distributed as Supporting Information for this article and referred to as LIAR version 2 (LIARv2), locally interpolated nitrate regression (LINR), and locally interpolated pH regression (LIPHR). Collectively they are referred to …


Dynamics Of Stony Coral And Octocoral Juvenile Assemblages Following Disturbance On Patch Reefs Of The Florida Reef Tract, Lucy A. Bartlett, Vanessa I. P. Brinkhuis, Rob R. Ruzicka, Michael A. Colella, Kathleen S. Lunz, Erin H. Leone, Pamela Hallock Jan 2018

Dynamics Of Stony Coral And Octocoral Juvenile Assemblages Following Disturbance On Patch Reefs Of The Florida Reef Tract, Lucy A. Bartlett, Vanessa I. P. Brinkhuis, Rob R. Ruzicka, Michael A. Colella, Kathleen S. Lunz, Erin H. Leone, Pamela Hallock

Marine Science Faculty Publications

In January 2010, reefs in the Upper and Middle Florida Keys experienced prolonged exposure to extremely cold water temperatures, below lethal thresholds for many reef organisms including corals. We examined post-disturbance juvenile assemblages of stony corals and octocorals on eight patch reefs, four of which were categorized as high impact and four as low impact, based on declines in stony-coral cover following disturbance. We established permanent quadrats to conduct field surveys in spring and fall of 2012 and 2013. Overall, juvenile abundances of both stony corals and octocorals were greater on low-impact sites, suggesting that those sites had higher recruitment …


Description And Mechanisms Of The Mid-Year Upwelling In The Southern Caribbean Sea From Remote Sensing And Local Data, Digna T. Rueda-Roa, Tal Ezer, Frank E. Muller-Karger Jan 2018

Description And Mechanisms Of The Mid-Year Upwelling In The Southern Caribbean Sea From Remote Sensing And Local Data, Digna T. Rueda-Roa, Tal Ezer, Frank E. Muller-Karger

Marine Science Faculty Publications

The southern Caribbean Sea experiences strong coastal upwelling between December and April due to the seasonal strengthening of the trade winds. A second upwelling was recently detected in the southeastern Caribbean during June–August, when local coastal wind intensities weaken. Using synoptic satellite measurements and in situ data, this mid-year upwelling was characterized in terms of surface and subsurface temperature structures, and its mechanisms were explored. The mid-year upwelling lasts 6–9 weeks with satellite sea surface temperature (SST) ~1–2° C warmer than the primary upwelling. Three possible upwelling mechanisms were analyzed: cross-shore Ekman transport (csET) due to alongshore winds, wind curl …


Using Satellite Laser Ranging To Measure Ice Mass Change In Greenland And Antarctica, Jennifer A. Bonin, Don P. Chambers, Minkang Cheng Jan 2018

Using Satellite Laser Ranging To Measure Ice Mass Change In Greenland And Antarctica, Jennifer A. Bonin, Don P. Chambers, Minkang Cheng

Marine Science Faculty Publications

A least squares inversion of satellite laser ranging (SLR) data over Greenland and Antarctica could extend gravimetry-based estimates of mass loss back to the early 1990s and fill any future gap between the current Gravity Recovery and Climate Experiment (GRACE) and the future GRACE Follow-On mission. The results of a simulation suggest that, while separating the mass change between Greenland and Antarctica is not possible at the limited spatial resolution of the SLR data, estimating the total combined mass change of the two areas is feasible. When the method is applied to real SLR and GRACE gravity series, we find …


A Conceptual View On Inertial Internal Waves In Relation To The Subinertial Flow On The Central West Florida Shelf, Ekatrina V. Maksimova Jan 2018

A Conceptual View On Inertial Internal Waves In Relation To The Subinertial Flow On The Central West Florida Shelf, Ekatrina V. Maksimova

Marine Science Faculty Publications

The study reported here focuses on inertial internal wave currents on the west Florida midshelf in 50 m depth. In situ observations showed that the seasonal shifts in stratification change both the frequency range of inertial internal waves and their modulation time scales. According to the analysis, the subinertial flow evolution time scales also undergo compatible seasonal variations, and the inertial internal wave currents appear to be temporally and spatially related to the subinertial flow. Specifically, the subinertial flow evolving on frontal-/quasi-geostrophic time scales appears to be accompanied by the near-inertial oscillations/inertia-gravity waves in corresponding small/finite Burger number regimes, respectively. …


Regional Acidification Trends In Florida Shellfish Estuaries: A 20+ Year Look At Ph, Oxygen, Temperature, And Salinity, Lisa L. Robbins, John T. Lisle Jan 2018

Regional Acidification Trends In Florida Shellfish Estuaries: A 20+ Year Look At Ph, Oxygen, Temperature, And Salinity, Lisa L. Robbins, John T. Lisle

Marine Science Faculty Publications

Increasing global CO2 and local land use changes coupled with increased nutrient pollution are threatening estuaries worldwide. Local changes of estuarine chemistry have been documented, but regional associations and trends comparing multiple estuaries latitudinally have not been evaluated. Rapid climate change has impacted the annual and decadal chemical trends in estuaries, with local ecosystem processes enhancing or mitigating the responses. Here, we compare pH, dissolved oxygen, temperature, and salinity data from 10 Florida shellfish estuaries and hundreds of shellfish bed stations. Over 80,000 measurements, spanning from 1980 to 2008, taken on Atlantic Ocean and West Florida coast showed significant …


An Alternative To Static Climatologies: Robust Estimation Of Open Ocean Co2 Variables And Nutrient Concentrations From T, S, And O2 Data Using Bayesian Neural Networks, Henry C. Bittig, Tobias Steinhoff, Hervé Claustre, Björn Fiedler, Nancy L. Williams, Raphaëlle Sauzède, Arne Körtzinger, Jean-Pierre Gattuso Jan 2018

An Alternative To Static Climatologies: Robust Estimation Of Open Ocean Co2 Variables And Nutrient Concentrations From T, S, And O2 Data Using Bayesian Neural Networks, Henry C. Bittig, Tobias Steinhoff, Hervé Claustre, Björn Fiedler, Nancy L. Williams, Raphaëlle Sauzède, Arne Körtzinger, Jean-Pierre Gattuso

Marine Science Faculty Publications

This work presents two new methods to estimate oceanic alkalinity (AT), dissolved inorganic carbon (CT), pH, and pCO2 from temperature, salinity, oxygen, and geolocation data. “CANYON-B” is a Bayesian neural network mapping that accurately reproduces GLODAPv2 bottle data and the biogeochemical relations contained therein. “CONTENT” combines and refines the four carbonate system variables to be consistent with carbonate chemistry. Both methods come with a robust uncertainty estimate that incorporates information from the local conditions. They are validated against independent GO-SHIP bottle and sensor data, and compare favorably to other state-of-the-art mapping methods. As “dynamic climatologies” they show comparable performance …


Utilizing The Drake Passage Time-Series To Understand Variability And Change In Subpolar Southern Ocean PCo2, Amanda R. Fay, Nicole S. Lovenduski, Galen A. Mckinley, David R. Munro, Colm Sweeney, Alison R. Gray, Peter Landschützer, Britton B. Stephens, Taro Takahashi, Nancy Williams Jan 2018

Utilizing The Drake Passage Time-Series To Understand Variability And Change In Subpolar Southern Ocean PCo2, Amanda R. Fay, Nicole S. Lovenduski, Galen A. Mckinley, David R. Munro, Colm Sweeney, Alison R. Gray, Peter Landschützer, Britton B. Stephens, Taro Takahashi, Nancy Williams

Marine Science Faculty Publications

The Southern Ocean is highly under-sampled for the purpose of assessing total carbon uptake and its variability. Since this region dominates the mean global ocean sink for anthropogenic carbon, understanding temporal change is critical. Underway measurements of pCO2 collected as part of the Drake Passage Time-series (DPT) program that began in 2002 inform our understanding of seasonally changing air–sea gradients in pCO2, and by inference the carbon flux in this region. Here, we utilize available pCO2 observations to evaluate how the seasonal cycle, interannual variability, and long-term trends in surface ocean pCO …


Assessment Of The Carbonate Chemistry Seasonal Cycles In The Southern Ocean From Persistent Observational Platforms, N. L. Williams, L. W. Juranek, R. A. Feely, J. L. Russell, K. S. Johnson, B. Hales Jan 2018

Assessment Of The Carbonate Chemistry Seasonal Cycles In The Southern Ocean From Persistent Observational Platforms, N. L. Williams, L. W. Juranek, R. A. Feely, J. L. Russell, K. S. Johnson, B. Hales

Marine Science Faculty Publications

Observations from Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM) biogeochemical profiling Argo floats are used to characterize the climatological seasonal cycles and drivers of dissolved inorganic carbon, total alkalinity, pH, the partial pressure of carbon dioxide (CO2), and the saturation state of aragonite at the surface and at 200 m across five Southern Ocean frontal regimes, including under sea ice. The Southern Ocean ranges from a temperature-dominated system in the northernmost Subtropical Zone to a biologically dominated system in the most poleward Seasonal Sea Ice Zone. In all zones, the ingassing or outgassing of CO2 …


Using Kinetic Energy Measurements From Altimetry To Detect Shifts In The Positions Of Fronts In The Southern Ocean, Don P. Chambers Jan 2018

Using Kinetic Energy Measurements From Altimetry To Detect Shifts In The Positions Of Fronts In The Southern Ocean, Don P. Chambers

Marine Science Faculty Publications

A novel analysis is performed utilizing cross-track kinetic energy (CKE) computed from along-track sea surface height anomalies. The midpoint of enhanced kinetic energy averaged over 3-year periods from 1993 to 2016 is determined across the Southern Ocean and examined to detect shifts in frontal positions, based on previous observations that kinetic energy is high around fronts in the Antarctic Circumpolar Current system due to jet instabilities. It is demonstrated that although the CKE does not represent the full eddy kinetic energy (computed from crossovers), the shape of the enhanced regions along ground tracks is the same, and CKE has a …


Hard Rock Landforms Generate 130 Km Ice Shelf Channels Through Water Focusing In Basal Corrugations, Hafeez Jeofry, Neil Ross, Anne Le Brocq, Alastair G. C. Graham, Jilu Li, Prasad Gogineni, Mathieu Morlighem, Thomas Jordan, Martin J. Siegert Jan 2018

Hard Rock Landforms Generate 130 Km Ice Shelf Channels Through Water Focusing In Basal Corrugations, Hafeez Jeofry, Neil Ross, Anne Le Brocq, Alastair G. C. Graham, Jilu Li, Prasad Gogineni, Mathieu Morlighem, Thomas Jordan, Martin J. Siegert

Marine Science Faculty Publications

Satellite imagery reveals flowstripes on Foundation Ice Stream parallel to ice flow, and meandering features on the ice-shelf that cross-cut ice flow and are thought to be formed by water exiting a well-organised subglacial system. Here, ice-penetrating radar data show flow-parallel hard-bed landforms beneath the grounded ice, and channels incised upwards into the ice shelf beneath meandering surface channels. As the ice transitions to flotation, the ice shelf incorporates a corrugation resulting from the landforms. Radar reveals the presence of subglacial water alongside the landforms, indicating a well-organised drainage system in which water exits the ice sheet as a point …


How Dynamic Are Ice-Stream Beds?, Damon Davies, Robert G. Bingham, Edward C. King, Andrew M. Smith, Alex M. Brisbourne, Matteo Spagnolo, Alastair G. C. Graham, Anna E. Hogg, David G. Vaughan Jan 2018

How Dynamic Are Ice-Stream Beds?, Damon Davies, Robert G. Bingham, Edward C. King, Andrew M. Smith, Alex M. Brisbourne, Matteo Spagnolo, Alastair G. C. Graham, Anna E. Hogg, David G. Vaughan

Marine Science Faculty Publications

Projections of sea-level rise contributions from West Antarctica's dynamically thinning ice streams contain high uncertainty because some of the key processes involved are extremely challenging to observe. An especially poorly observed parameter is sub-decadal stability of ice-stream beds, which may be important for subglacial traction, till continuity and landform development. Only two previous studies have made repeated geophysical measurements of ice-stream beds at the same locations in different years, but both studies were limited in spatial extent. Here, we present the results from repeat radar measurements of the bed of Pine Island Glacier, West Antarctica, conducted 3–6 years apart, along …


Deglaciation And Future Stability Of The Coats Land Ice Margin, Antarctica, Dominic A. Hodgson, Kelly Hogan, James M. Smith, James A. Smith, Claus-Dieter Hillenbrand, Alastair G. C. Graham, Peter Fretwell, Claire Allen, Vicky Peck, Jan-Erik Arndt, Boris Dorschel, Christian Hübscher, Andrew M. Smith, Robert Larter Jan 2018

Deglaciation And Future Stability Of The Coats Land Ice Margin, Antarctica, Dominic A. Hodgson, Kelly Hogan, James M. Smith, James A. Smith, Claus-Dieter Hillenbrand, Alastair G. C. Graham, Peter Fretwell, Claire Allen, Vicky Peck, Jan-Erik Arndt, Boris Dorschel, Christian Hübscher, Andrew M. Smith, Robert Larter

Marine Science Faculty Publications

The East Antarctic Ice Sheet discharges into the Weddell Sea via the Coats Land ice margin. We have used geophysical data to determine the changing ice-sheet configuration in this region through its last glacial advance and Holocene retreat and to identify constraints on its future stability. Methods included high-resolution multibeam bathymetry, sub-bottom profiles, seismic-reflection profiles, sediment core analysis and satellite altimetry. These provide evidence that Coats Land glaciers and ice streams merged with the palaeo-Filchner Ice Stream during the last glacial advance. Retreat of this ice stream from 12 848 to 8351 cal. yr BP resulted in its progressive southwards …


Insights Into The Biodiversity, Behavior, And Bioluminescence Of Deep-Sea Organisms Using Molecular And Maritime Technology, Steven H. D. Haddock, Brad A. Seibel Jan 2018

Insights Into The Biodiversity, Behavior, And Bioluminescence Of Deep-Sea Organisms Using Molecular And Maritime Technology, Steven H. D. Haddock, Brad A. Seibel

Marine Science Faculty Publications

Since its founding, the Monterey Bay Aquarium Research Institute (MBARI) has pioneered unique capabilities for accessing the deep ocean and its inhabitants through focused peer relationships between scientists and engineers. This focus has enabled breakthroughs in our understanding of life in the sea, leading to fundamental advances in describing the biology and the ecology of open-ocean and deep-sea animals. David Packard’s founding principle was the application of technological advances to studying the deep ocean, in part because he recognized the critical importance of this habitat in a global context. Among other fields, MBARI’s science has benefited from applying novel methodologies …