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A Long-Term, Interdisciplinary Study of Deep Sea to Coast Connectivity in the Northeasten Gulf of Mexico
Title
A Long-Term, Interdisciplinary Study of Deep Sea to Coast Connectivity in the Northeasten Gulf of Mexico.
Creator
Deep-C Consortium, Gulf of Mexico Research Initiative
Date Issued
2013-02-27, 2013-02-28
Identifier
FSU_HPUA_2015_038_AllHandsFeb_002
Format
Document (PDF)
A Preliminary Assessment of Desoto Canyon Sediment Macrofauna: Comparison to Baseline
Title
A Preliminary Assessment of Desoto Canyon Sediment Macrofauna: Comparison to Baseline.
Creator
Deep-C Consortium, Florida State University, Earth, Ocean and Atmospheric Science, Gulf of Mexico Research Initiative, Baco, A. R., Shantharam, A., Rowe, G., Wei, C-L.
Date Issued
2013-02
Identifier
FSU_HPUA_2015_038_AllHandsPoster_001
Format
Document (PDF)
A Time-Series of Surface Oil Distribution Based on SAR and Regional Difference in Megafauna Abundance Related to Geomorphology and Depth Gradients in DeSoto Canyon
Title
A Time-Series of Surface Oil Distribution Based on SAR and Regional Difference in Megafauna Abundance Related to Geomorphology and Depth Gradients in DeSoto Canyon.
Creator
Deep-C Consortium, State of Florida Institute of Oceanography, Florida State University, Ecogig, Gulf of Mexico Research Initiative, MacDonald, Ian
Date Issued
2013-09-11
Identifier
FSU_HPUA_2015_038_AllHandsSept_016
Format
Document (PDF)
Adding Stable Carbon Isotopes Improves Model Representation Of The Role Of Microbial Communities In Peatland Methane Cycling
Title
Adding Stable Carbon Isotopes Improves Model Representation Of The Role Of Microbial Communities In Peatland Methane Cycling.
Creator
Deng, Jia, McCalley, Carmody K., Frolking, Steve, Chanton, Jeff, Crill, Patrick, Varner, Ruth, Tyson, Gene, Rich, Virginia, Hines, Mark, Saleska, Scott R., Li, Changsheng
Abstract/Description
Climate change is expected to have significant and uncertain impacts on methane (CH4) emissions from northern peatlands. Biogeochemical models can extrapolate site-specificCH(4) measurements to larger scales and predict responses of CH4 emissions to environmental changes. However, these models include considerable uncertainties and limitations in representing CH4 production, consumption, and transport processes. To improve predictions of CH4 transformations, we incorporated acetate and stable...
Show moreClimate change is expected to have significant and uncertain impacts on methane (CH4) emissions from northern peatlands. Biogeochemical models can extrapolate site-specificCH(4) measurements to larger scales and predict responses of CH4 emissions to environmental changes. However, these models include considerable uncertainties and limitations in representing CH4 production, consumption, and transport processes. To improve predictions of CH4 transformations, we incorporated acetate and stable carbon (C) isotopic dynamics associated with CH4 cycling into a biogeochemistry model, DNDC. By including these new features, DNDC explicitly simulates acetate dynamics and the relative contribution of acetotrophic and hydro-genotrophic methanogenesis (AM and HM) to CH4 production, and predicts the C isotopic signature (delta C-13) in soil C pools and emitted gases. When tested against biogeochemical and microbial community observations at two sites in a zone of thawing permafrost in a subarctic peatland in Sweden, the new formulation substantially improved agreement with CH4 production pathways and delta C-13 in emitted CH4 (delta C-13-CH4), a measure of the integrated effects of microbial production and consumption, and of physical transport. We also investigated the sensitivity of simulated delta C-13-CH4 to C isotopic composition of substrates and, to fractionation factors for CH4 production (alpha(AM) and alpha(HM)), CH4 oxidation (alpha(MO)), and plant-mediated CH4 transport (alpha(TP)). The sensitivity analysis indicated that the delta C-13-CH4 is highly sensitive to the factors associated with microbial metabolism (alpha(AM), alpha(HM), and alpha(MO)). The model framework simulating stable C isotopic dynamics provides a robust basis for better constraining and testing microbial mechanisms in predicting CH4 cycling in peatlands.
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Date Issued
2017-06
Identifier
FSU_libsubv1_wos_000406239300036, 10.1002/2016MS000817
Format
Citation
Advanced Molecular Techniques Provide New Rigorous Tools For Characterizing Organic Matter Quality In Complex Systems
Title
Advanced Molecular Techniques Provide New Rigorous Tools For Characterizing Organic Matter Quality In Complex Systems.
Creator
Wilson, Rachel M., Tfaily, Malak M.
Abstract/Description
Carbon flux rates are widely understood to be substrate controlled; however, characterizing substrate quality continues to be a challenge. We suggest that, while optical measurements have their place, they are not the only, or the best, tool for characterizing organic matter quality. Nominal oxidation state of the carbon provides a thermodynamically relevant measure, which could be used as a metric of organic matter quality. Calculating nominal oxidation state of the carbon requires a suite...
Show moreCarbon flux rates are widely understood to be substrate controlled; however, characterizing substrate quality continues to be a challenge. We suggest that, while optical measurements have their place, they are not the only, or the best, tool for characterizing organic matter quality. Nominal oxidation state of the carbon provides a thermodynamically relevant measure, which could be used as a metric of organic matter quality. Calculating nominal oxidation state of the carbon requires a suite of advanced complementary analysis but is then trivial to calculate from the resulting data sets.
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Date Issued
2018-06-01
Identifier
FSU_libsubv1_wos_000438667200001, 10.1029/2018JG004525
Format
Citation
After-The-Fact Estimations of the Calcareous Nannoplankton Composition and Quantity Present During the 2010 Macondo Oil Spill in the NE Gulf of Mexico: A Work in Progress
Title
After-The-Fact Estimations of the Calcareous Nannoplankton Composition and Quantity Present During the 2010 Macondo Oil Spill in the NE Gulf of Mexico: A Work in Progress.
Creator
Deep-C Consortium, Florida State University, University of South Florida, Valdosta State University, University of West Florida, Agbali, Aisha E., Cruz, Jarrett W., Flower,...
Show moreDeep-C Consortium, Florida State University, University of South Florida, Valdosta State University, University of West Florida, Agbali, Aisha E., Cruz, Jarrett W., Flower, Benjamin P., Foley, Susan M., Hollander, David, Jeffrey, Wade H., Myers, Nicholas R., Nienow, James A., Snyder, Richard A., Wise, Sherwood W. Jr.
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Date Issued
2013-02
Identifier
FSU_HPUA_2015_038_AllHandsPoster_023
Format
Document (PDF)
Allogenic And Autogenic Signals In The Stratigraphic Record Of The Deep-sea Bengal Fan
Title
Allogenic And Autogenic Signals In The Stratigraphic Record Of The Deep-sea Bengal Fan.
Creator
Blum, Mike, Rogers, Kimberly, Gleason, James, Najman, Yani, Cruz, Jarrett, Fox, Lyndsey
Abstract/Description
The Himalayan-sourced Ganges-Brahmaputra river system and the deep-sea Bengal Fan represent Earth's largest sediment-dispersal system. Here we present detrital zircon U-Pb provenance data from Miocene to middle Pleistocene Bengal Fan turbidites, and evaluate the influence of allogenic forcing vs. autogenic processes on signal propagation from the Himalaya to the deep sea. Our data record the strong tectonic and climatic forcing characteristic of the Himalayan system: after up to 2500 km of...
Show moreThe Himalayan-sourced Ganges-Brahmaputra river system and the deep-sea Bengal Fan represent Earth's largest sediment-dispersal system. Here we present detrital zircon U-Pb provenance data from Miocene to middle Pleistocene Bengal Fan turbidites, and evaluate the influence of allogenic forcing vs. autogenic processes on signal propagation from the Himalaya to the deep sea. Our data record the strong tectonic and climatic forcing characteristic of the Himalayan system: after up to 2500 km of river transport, and >1400 km of transport by turbidity currents, the U-Pb record faithfully represents Himalayan sources. Moreover, specific U-Pb populations record Miocene integration of the Brahmaputra drainage with the Asian plate, as well as the rapid Plio-Pleistocene incision through, and exhumation of, the eastern Himalayan syntaxis. The record is, however, biased towards glacial periods when rivers were extended across the shelf in response to climate-forced sea-level fall, and discharged directly to slope canyons. Finally, only part of the record represents a Ganges or Brahmaputra provenance end-member, and most samples represent mixing from the two systems. Mixing or the lack thereof likely represents the fingerprint of autogenic delta-plain avulsions, which result in the two rivers delivering sediment separately to a shelf-margin canyon or merging together as they do today.
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Date Issued
2018-05-22
Identifier
FSU_libsubv1_wos_000432655200008, 10.1038/s41598-018-25819-5
Format
Citation
Allogenic And Autogenic Signals In The Stratigraphic Record Of The Deep-sea Bengal Fan (vol 8, 7973, 2018)
Title
Allogenic And Autogenic Signals In The Stratigraphic Record Of The Deep-sea Bengal Fan (vol 8, 7973, 2018).
Creator
Blum, Mike, Rogers, Kimberly, Gleason, James, Najman, Yani, Cruz, Jarrett, Fox, Lyndsey
Date Issued
2018-08-10
Identifier
FSU_libsubv1_wos_000441302400001, 10.1038/s41598-018-30160-y
Format
Citation
Alpha- and Gammaproteobacterial Methanotrophs Codominate the Active Methane-Oxidizing Communities in an Acidic Boreal Peat Bog.
Title
Alpha- and Gammaproteobacterial Methanotrophs Codominate the Active Methane-Oxidizing Communities in an Acidic Boreal Peat Bog.
Creator
Esson, Kaitlin C, Lin, Xueju, Kumaresan, Deepak, Chanton, Jeffrey P, Murrell, J Colin, Kostka, Joel E
Abstract/Description
The objective of this study was to characterize metabolically active, aerobic methanotrophs in an ombrotrophic peatland in the Marcell Experimental Forest, in Minnesota. Methanotrophs were investigated in the field and in laboratory incubations using DNA-stable isotope probing (SIP), expression studies on particulate methane monooxygenase (pmoA) genes, and amplicon sequencing of 16S rRNA genes. Potential rates of oxidation ranged from 14 to 17 μmol of CH4g dry weight soil(-1)day(-1) Within...
Show moreThe objective of this study was to characterize metabolically active, aerobic methanotrophs in an ombrotrophic peatland in the Marcell Experimental Forest, in Minnesota. Methanotrophs were investigated in the field and in laboratory incubations using DNA-stable isotope probing (SIP), expression studies on particulate methane monooxygenase (pmoA) genes, and amplicon sequencing of 16S rRNA genes. Potential rates of oxidation ranged from 14 to 17 μmol of CH4g dry weight soil(-1)day(-1) Within DNA-SIP incubations, the relative abundance of methanotrophs increased from 4% in situ to 25 to 36% after 8 to 14 days. Phylogenetic analysis of the(13)C-enriched DNA fractions revealed that the active methanotrophs were dominated by the genera Methylocystis(type II;Alphaproteobacteria),Methylomonas, and Methylovulum(both, type I;Gammaproteobacteria). In field samples, a transcript-to-gene ratio of 1 to 2 was observed for pmoA in surface peat layers, which attenuated rapidly with depth, indicating that the highest methane consumption was associated with a depth of 0 to 10 cm. Metagenomes and sequencing of cDNA pmoA amplicons from field samples confirmed that the dominant active methanotrophs were Methylocystis and Methylomonas Although type II methanotrophs have long been shown to mediate methane consumption in peatlands, our results indicate that members of the genera Methylomonas and Methylovulum(type I) can significantly contribute to aerobic methane oxidation in these ecosystems.
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Date Issued
2016-04-04
Identifier
FSU_pmch_26873322, 10.1128/AEM.03640-15, PMC4959502, 26873322, 26873322, AEM.03640-15
Format
Citation
Aluminium In The North Atlantic Ocean And The Labrador Sea (geotraces Ga01 Section)
Title
Aluminium In The North Atlantic Ocean And The Labrador Sea (geotraces Ga01 Section): Roles Of Continental Inputs And Biogenic Particle Removal.
Creator
Barraqueta, Jan-Lukas Menzel, Schlosser, Christian, Planquette, Helene, Gourain, Arthur, Cheize, Marie, Boutorh, Julia, Shelley, Rachel, Pereira, Leonardo Contreira, Gledhill,...
Show moreBarraqueta, Jan-Lukas Menzel, Schlosser, Christian, Planquette, Helene, Gourain, Arthur, Cheize, Marie, Boutorh, Julia, Shelley, Rachel, Pereira, Leonardo Contreira, Gledhill, Martha, Hopwood, Mark J., Lacan, Francois, Lherminier, Pascale, Sarthou, Geraldine, Achterberg, Eric P.
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Abstract/Description
The distribution of dissolved aluminium (dAl) in the water column of the North Atlantic and Labrador Sea was studied along GEOTRACES section GA01 to unravel the sources and sinks of this element. Surface water dAl concentrations were low (median of 2.5 nM) due to low aerosol deposition and removal by biogenic particles (i.e. phytoplankton cells). However, surface water dAl concentrations were enhanced on the Iberian and Greenland shelves (up to 30.9 nM) due to continental inputs (rivers,...
Show moreThe distribution of dissolved aluminium (dAl) in the water column of the North Atlantic and Labrador Sea was studied along GEOTRACES section GA01 to unravel the sources and sinks of this element. Surface water dAl concentrations were low (median of 2.5 nM) due to low aerosol deposition and removal by biogenic particles (i.e. phytoplankton cells). However, surface water dAl concentrations were enhanced on the Iberian and Greenland shelves (up to 30.9 nM) due to continental inputs (rivers, glacial flour, and ice melt). Dissolved Al in surface waters scaled negatively with chlorophyll a and biogenic silica (opal) concentrations. The abundance of diatoms exerted a significant (p < 0.01) control on the surface particulate Al (pAl) to dAl ratios by decreasing dAl levels and increasing pAl levels. Dissolved Al concentrations generally increased with depth and correlated strongly with silicic acid (R-2 > 0.76) west of the Iberian Basin, suggesting net release of dAl at depth during remineralization of sinking opal-containing particles. Enrichment of dAl at near-bottom depths was observed due to the resuspension of sediments. The highest dAl concentrations (up to 38.7 nM) were observed in Mediterranean Outflow Waters, which act as a major source of dAl to mid-depth waters of the eastern North Atlantic. This study clearly shows that the vertical and lateral distributions of dAl in the North Atlantic differ when compared to other regions of the Atlantic and global oceans. Responsible for these large inter- and intra-basin differences are the large spatial variabilities in the main Al source, atmospheric deposition, and the main Al sink, particle scavenging by biogenic particles.
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Date Issued
2018-08-30
Identifier
FSU_libsubv1_wos_000443197700003, 10.5194/bg-15-5271-2018
Format
Citation
Analysis of Bragg Scattering of Oil Types Under Radar Microwaves
Title
Analysis of Bragg Scattering of Oil Types Under Radar Microwaves.
Creator
Deep-C Consortium, Florida State University, Garcia, Oscar, MacDonald, Ian, Hale, Andrew
Date Issued
2013-09-11
Identifier
FSU_HPUA_2015_038_AllHandsSept_006
Format
Document (PDF)
Analysis of Drilling Mud Olefins to Study the Origin of the Recent MC252 Oil Sheen
Title
Analysis of Drilling Mud Olefins to Study the Origin of the Recent MC252 Oil Sheen.
Creator
Deep-C Consortium, Woods Hole Oceanographic Institute, Reddy, Chris, Aeppli, Christoph
Date Issued
2013-09-13
Identifier
FSU_HPUA_2015_038_AllHandsSept_001
Format
Document (PDF)
Analysis of Observations to Understand the Physics of the Connectivity Between the Deep Sea and the Coast Through the DeSoto Canyon
Title
Analysis of Observations to Understand the Physics of the Connectivity Between the Deep Sea and the Coast Through the DeSoto Canyon.
Creator
Deep-C Consortium, Clarke, Allan J., Van Gorder, Stephen, Wienders, Nicolas, Hamilton, Peter, Speer, Kevin
Date Issued
2013-09-10
Identifier
FSU_HPUA_2015_038_AllHandsSept_005
Format
Document (PDF)
Anatomy and Osteohistology of the basal hadrosaurid dinosaur Eotrachodon from the uppermost Santonian (Cretaceous) of southern appalachia
Title
Anatomy and Osteohistology of the basal hadrosaurid dinosaur Eotrachodon from the uppermost Santonian (Cretaceous) of southern appalachia.
Creator
Prieto-Marquez, Albert, Erickson, Gregory M., Ebersole, Jun A.
Abstract/Description
The cranial and postcranial anatomy of the basal hadrosaurid dinosaur Eotrachodon orientalis, from the uppermost Santonian of southern Appalachia (southeastern U.S.A.), is described in detail. This animal is the only known pre-Campanian non-lambeosaurine hadrosaurid, and the most complete hadrosauroid known from Appalachia. E. orientalis possesses a mosaic of plesiomorphic and derived characters in the context of Hadrosauroidea. Characters shared with basal hadrosauroids include a short and...
Show moreThe cranial and postcranial anatomy of the basal hadrosaurid dinosaur Eotrachodon orientalis, from the uppermost Santonian of southern Appalachia (southeastern U.S.A.), is described in detail. This animal is the only known pre-Campanian non-lambeosaurine hadrosaurid, and the most complete hadrosauroid known from Appalachia. E. orientalis possesses a mosaic of plesiomorphic and derived characters in the context of Hadrosauroidea. Characters shared with basal hadrosauroids include a short and sloping maxillary ectopterygoid shelf, caudally prominent maxillary jugal process, one functional tooth per alveolus on the maxillary occlusal plane, a jugal rostral process with a shallow caudodorsal margin and medioventrally facing articular facet, a vertical dentary coronoid process with a poorly expanded apex, and tooth crowns with accessory ridges. Derived characters shared with other hadrosaurids include a circumnarial depression compartmented into three fossae (as in brachylophosaurins and Edmontosaurus), a thin everted premaxillary oral margin (as in Gryposaurus, Prosaurolophus, and Saurolophus), and a maxilla with a deep and rostrocaudally extensive rostrodorsal region with a steeply sloping premaxillary margin (as in Gryposaurus). Eotrachodon orientalis differs primarily from the other hadrosauroid from the Mooreville Chalk of Alabama, Lophorhothon atopus, in having a slender and crestless nasal whose caudodorsal margin is not invaded by the circumnarial depression. Hadrosaurus foulkii, the only other known hadrosaurid from Appalachia, is distinct from E. orientalis in having dentary teeth lacking accessory ridges and a dorsally curved shaft of the ischium. A histological section of the tibia of the E. orientalis holotype (MSC 7949) suggests that this individual was actively growing at the time of death and, thus, had the potential to become a larger animal later in development.
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Date Issued
2016-04-14
Identifier
FSU_libsubv1_wos_000374374200003, 10.7717/peerj.1872
Format
Citation
Arbitrary Shaped Beam Scattering From A Chiral-coated Conducting Object With Arbitrary Monochromatic Illumination
Title
Arbitrary Shaped Beam Scattering From A Chiral-coated Conducting Object With Arbitrary Monochromatic Illumination.
Creator
Wang, Mingjun, Zhang, Huayong, Ke, Xizheng, Liu, Guosheng, Ouyang, Xiaoping
Abstract/Description
An exact semi-analytical method of calculating the scattered fields from a chiral-coated conducting object under arbitrary shaped beam illumination is developed. The scattered fields and the fields within the chiral coating are expanded in terms of appropriate spherical vector wave functions. The unknown expansion coefficients are determined by solving an infinite system of linear equations derived using the method of moments technique and the boundary conditions. For incidence of a Gaussian...
Show moreAn exact semi-analytical method of calculating the scattered fields from a chiral-coated conducting object under arbitrary shaped beam illumination is developed. The scattered fields and the fields within the chiral coating are expanded in terms of appropriate spherical vector wave functions. The unknown expansion coefficients are determined by solving an infinite system of linear equations derived using the method of moments technique and the boundary conditions. For incidence of a Gaussian beam, circularly polarized wave, zero-order Bessel beam and Hertzian electric dipole radiation on a chiral-coated conducting spheroid and a chiral-coated conducting circular cylinder of finite length, the normalized differential scattering cross sections are evaluated and discussed briefly.
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Date Issued
2018-08-17
Identifier
FSU_libsubv1_wos_000441876700053, 10.1038/s41598-018-30596-2
Format
Citation
Artificial Water Sediment Regulation Scheme Influences Morphology, Hydrodynamics And Nutrient Behavior In The Yellow River Estuary
Title
Artificial Water Sediment Regulation Scheme Influences Morphology, Hydrodynamics And Nutrient Behavior In The Yellow River Estuary.
Creator
Xu, Bochao, Yang, Disong, Burnett, William C., Ran, Xiangbin, Yu, Zhigang, Gao, Maosheng, Diao, Shaobo, Jiang, Xueyan
Abstract/Description
Anthropogenic controls on water and sediment may play important roles in river system transformations and morphological evolution, which could further affect coastal hydrodynamics and nutrient behavior. We used geochemical tracers to evaluate the influence of an intentional large release of water and sediment during the so-called "Water Sediment Regulation Scheme" (WSRS) on estuarine morphology, hydrodynamics and nutrients in the Yellow River estuary, China. We discovered that there was a...
Show moreAnthropogenic controls on water and sediment may play important roles in river system transformations and morphological evolution, which could further affect coastal hydrodynamics and nutrient behavior. We used geochemical tracers to evaluate the influence of an intentional large release of water and sediment during the so-called "Water Sediment Regulation Scheme" (WSRS) on estuarine morphology, hydrodynamics and nutrients in the Yellow River estuary, China. We discovered that there was a newly formed small delta in the river mouth after the 2013 WSRS. This new morphologic feature altered terrestrial material distribution patterns from a single plume to a two-plume pattern within the estuary. Our results show that the WSRS significantly influenced the study area in the following ways: (1) Radium and nutrient concentrations were significantly elevated (two to four times), especially along the two river outlets. (2) Estuarine mixing was about two times stronger during WSRS than before. Average aerial mixing rates before and during WSRS were 50 +/- 26 km(2) d(-1) and 89 +/- 51 km(2) d(-1), respectively. (3) Our data is consistent with P limitation and suggest that stoichiometrically based P limitation was even more severe during WSRS. (4) All river-derived nutrients were thoroughly consumed within one to two weeks after entry to near-shore waters. (5) The extent of the area influenced by terrestrial nutrients was two to three times greater during WSRS. Human influence, such as triggered by WSRS regulations, should thus be considered when studying biogeochemical processes and nutrient budgets in situations like the Yellow River estuary. (C) 2016 Elsevier B.V. All rights reserved.
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Date Issued
2016-08
Identifier
FSU_libsubv1_wos_000378953700008, 10.1016/j.jhydrol.2016.05.024
Format
Citation
Assessing the Radiative Effects of Global Ice Clouds Based on CloudSat and CALIPSO Measurements
Title
Assessing the Radiative Effects of Global Ice Clouds Based on CloudSat and CALIPSO Measurements.
Creator
Hong, Yulan, Liu, Guosheng, Li, J.-L. F.
Abstract/Description
Although it is well established that cirrus warms Earth, the radiative effect of the entire spectrum of ice clouds is not well understood. In this study, the role of all ice clouds in Earth's radiation budget is investigated by performing radiative transfer modeling using ice cloud properties retrieved from CloudSat and CALIPSO measurements as inputs. Results show that, for the 2008 period, the warming effect (similar to 21.8 +/- 5.4 W m(-2)) induced by ice clouds trapping longwave radiation...
Show moreAlthough it is well established that cirrus warms Earth, the radiative effect of the entire spectrum of ice clouds is not well understood. In this study, the role of all ice clouds in Earth's radiation budget is investigated by performing radiative transfer modeling using ice cloud properties retrieved from CloudSat and CALIPSO measurements as inputs. Results show that, for the 2008 period, the warming effect (similar to 21.8 +/- 5.4 W m(-2)) induced by ice clouds trapping longwave radiation exceeds their cooling effect (similar to-16.7 +/- 1.7 W m(-2)) caused by shortwave reflection, resulting in a net warming effect (similar to 5.1 +/- 3.8 W m(-2)) globally on the earthatmosphere system. The net warming is over 15 W m(-2) in the tropical deep convective regions, whereas cooling occurs in the midlatitudes, which is less than 10 W m(-2) in magnitude. Seasonal variations of ice cloud radiative effects are evident in the midlatitudes where the net effect changes from warming during winter to cooling during summer, whereas warming occurs all year-round in the tropics. Ice cloud optical depth t is shown to be an important factor in determining the sign and magnitude of the net radiative effect. Ice clouds with tau < 4.6 display a warming effect with the largest contributions from those with tau approximate to 1.0. In addition, ice clouds cause vertically differential heating and cooling of the atmosphere, particularly with strong heating in the upper troposphere over the tropics. At Earth's surface, ice clouds produce a cooling effect no matter how small the tau value is.
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Date Issued
2016-11
Identifier
FSU_libsubv1_wos_000386205900006, 10.1175/JCLI-D-15-0799.1
Format
Citation
Atmospheric forcing during active convection in the Labrador Sea and its impact on mixed-layer depth
Title
Atmospheric forcing during active convection in the Labrador Sea and its impact on mixed-layer depth.
Creator
Schulze, Lena M., Pickart, Robert S., Moore, G. W. K.
Abstract/Description
Hydrographic data from the Labrador Sea collected in February-March 1997, together with atmospheric reanalysis fields, are used to explore relationships between the air-sea fluxes and the observed mixed-layer depths. The strongest winds and highest heat fluxes occurred in February, due to the nature and tracks of the storms. While greater numbers of storms occurred earlier and later in the winter, the storms in February followed a more organized track extending from the Gulf Stream region to...
Show moreHydrographic data from the Labrador Sea collected in February-March 1997, together with atmospheric reanalysis fields, are used to explore relationships between the air-sea fluxes and the observed mixed-layer depths. The strongest winds and highest heat fluxes occurred in February, due to the nature and tracks of the storms. While greater numbers of storms occurred earlier and later in the winter, the storms in February followed a more organized track extending from the Gulf Stream region to the Irminger Sea where they slowed and deepened. The canonical low-pressure system that drives convection is located east of the southern tip of Greenland, with strong westerly winds advecting cold air off the ice edge over the warm ocean. The deepest mixed layers were observed in the western interior basin, although the variability in mixed-layer depth was greater in the eastern interior basin. The overall trend in mixed-layer depth through the winter in both regions of the basin was consistent with that predicted by a 1-D mixed-layer model. We argue that the deeper mixed layers in the west were due to the enhanced heat fluxes on that side of the basin as opposed to oceanic preconditioning.
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Date Issued
2016-09
Identifier
FSU_libsubv1_wos_000386913200024, 10.1002/2015JC011607
Format
Citation
Bathymetric features of the Deep-C Desoto Canyon study area
Title
Bathymetric features of the Deep-C Desoto Canyon study area.
Creator
Deep-C Consortium, Earth, Ocean and Atmospheric Science, Florida State University, MacDonald, Ian
Date Issued
2012-08-21, 2012-08-22
Identifier
FSU_HPUA_2015_038_AllHandsAug_017
Format
Document (PDF)
Bias characterization of CrIS shortwave temperature sounding channels using fast NLTE model and GFS forecast field
Title
Bias characterization of CrIS shortwave temperature sounding channels using fast NLTE model and GFS forecast field.
Creator
Yin, Mengtao
Abstract/Description
The strong nonlocal thermal equilibrium (NLTE) emission in the upper atmosphere impedes the usage of Cross-track Infrared Sounder (CrIS) temperature channels near 4.3 mu m in the operational data assimilation. This study explores the bias characteristics of those temperature channels near 4.3 mu m with and without a fast NLTE model implemented in the Community Radiative Transfer Model (CRTM). It is shown that the biases of those temperature channels can reach up to 12K and are dramatically...
Show moreThe strong nonlocal thermal equilibrium (NLTE) emission in the upper atmosphere impedes the usage of Cross-track Infrared Sounder (CrIS) temperature channels near 4.3 mu m in the operational data assimilation. This study explores the bias characteristics of those temperature channels near 4.3 mu m with and without a fast NLTE model implemented in the Community Radiative Transfer Model (CRTM). It is shown that the biases of those temperature channels can reach up to 12K and are dramatically reduced to below 4K during daytime by the fast NLTE model with small differences from the nighttime biases. However, the biases after applying the NLTE correction remain large for CrIS upper atmospheric temperature channels during both daytime and nighttime. A further investigation suggests that the remaining biases in those temperature channels mainly originate from the cold biases in the stratospheric temperature profiles of National Center for Environmental Prediction Global Forecast System (GFS) forecasts as input to CRTM. The cold biases reach the maximum of about 8K near the tropics at about 1hPa, decreasing toward higher latitudes and lower altitudes.
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Date Issued
2016-02-16
Identifier
FSU_libsubv1_wos_000371481700014, 10.1002/2015JD023876
Format
Citation
Bigeochemical Radiocarbon Analysis of the Gulf Oil Spill: Sediments, Plankton and Coastal Fauna: Tracers in the Gulf
Title
Bigeochemical Radiocarbon Analysis of the Gulf Oil Spill: Sediments, Plankton and Coastal Fauna: Tracers in the Gulf.
Creator
Deep-C Consortium, Chanton, Jeffrey, Cherrier, Jennifer, Magen, Cedric, Sarkadee-Adoo, Judith, Boye, Samantha B., Hollander, David J., Graham, W. Monte, Brunner, Charlotte A.,...
Show moreDeep-C Consortium, Chanton, Jeffrey, Cherrier, Jennifer, Magen, Cedric, Sarkadee-Adoo, Judith, Boye, Samantha B., Hollander, David J., Graham, W. Monte, Brunner, Charlotte A., Bosman, Samantha, Mickel, Alejandra, Passow, Uta, Larson, Bekka, Brooks, Greg, Asper, Vernon
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Date Issued
2013-02
Identifier
FSU_HPUA_2015_038_AllHandsPoster_002
Format
Document (PDF)
Biogeochemical Radiocarbon Analysis of the Gulf Oil Spill: Sediments, Plankton and Coastal Fauna. Or Tracers in the Gulf
Title
Biogeochemical Radiocarbon Analysis of the Gulf Oil Spill: Sediments, Plankton and Coastal Fauna. Or Tracers in the Gulf.
Creator
Deep-C Consortium, Earth, Ocean and Atmospheric Science, Florida State University, Chanton, Jeffrey, Cherrier, Jennifer, Magen, Cedric, Sarkadee-Adoo, Judith, Joye, Samantha B.,...
Show moreDeep-C Consortium, Earth, Ocean and Atmospheric Science, Florida State University, Chanton, Jeffrey, Cherrier, Jennifer, Magen, Cedric, Sarkadee-Adoo, Judith, Joye, Samantha B., Hollander, David J., Graham, W. Monte, Brunner, Charlotte A., Bosman, Samantha, Mickel, Alejandra, Passow, Uta, Asper, Vernon, Zhao, Tingting
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Date Issued
2013-09-10
Identifier
FSU_HPUA_2015_038_AllHandsSept_003
Format
Document (PDF)
biological pump in the Costa Rica Dome
Title
The biological pump in the Costa Rica Dome: An open ocean upwelling system with high new production and low export.
Creator
Stukel, Michael R, Benitez-Nelson, Claudia R, Decima, Moira, Taylor, Andrew G, Buchwald, Carolyn, Landry, Michael R
Abstract/Description
The Costa Rica Dome is a picophytoplankton-dominated, open-ocean upwelling system in the Eastern Tropical Pacific that overlies the ocean’s largest oxygen minimum zone. To investigate the efficiency of the biological pump in this unique area, we used shallow (90-150 m) drifting sediment traps and 234Th:238U deficiency measurements to determine export fluxes of carbon, nitrogen, and phosphorus in sinking particles. Simultaneous in situ measurements of nitrate uptake allowed us to assess the...
Show moreThe Costa Rica Dome is a picophytoplankton-dominated, open-ocean upwelling system in the Eastern Tropical Pacific that overlies the ocean’s largest oxygen minimum zone. To investigate the efficiency of the biological pump in this unique area, we used shallow (90-150 m) drifting sediment traps and 234Th:238U deficiency measurements to determine export fluxes of carbon, nitrogen, and phosphorus in sinking particles. Simultaneous in situ measurements of nitrate uptake allowed us to assess the expected balance of new and export production. While f-ratios (new:total production) were reasonably high (0.36 ± 0.12, mean ± std. dev.), export efficiencies were considerably lower. Sediment traps suggested e-ratios (export/14C-primary production) at 90-100 m ranging from 0.053-0.067. ThE-ratios (234Th disequilibrium-derived export) ranged from 0.038-0.088. C:N and N:P stoichiometries of sinking material were both greater than canonical (Redfield) ratios or measured C:N of suspended particulates, and they increased with depth, suggesting that both nitrogen and phosphorus were preferentially remineralized from sinking particles. Our results are consistent with an ecosystem in which mesozooplankton play a major role in energy transfer to higher trophic levels but are relatively inefficient in mediating vertical carbon flux to depth, leading to an imbalance between new production and sinking flux.
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Date Issued
2016-03-01
Identifier
FSU_libsubv1_scholarship_submission_1509389454_4ff81645, 10.1093/plankt/fbv097
Format
Citation
biological pump in the Costa Rica Dome
Title
The biological pump in the Costa Rica Dome: an open-ocean upwelling system with high new production and low export..
Creator
Stukel, Michael R, Benitez-Nelson, Claudia R, Décima, Moira, Taylor, Andrew G, Buchwald, Carolyn, Landry, Michael R
Abstract/Description
The Costa Rica Dome is a picophytoplankton-dominated, open-ocean upwelling system in the Eastern Tropical Pacific that overlies the ocean's largest oxygen minimum zone. To investigate the efficiency of the biological pump in this unique area, we used shallow (90-150 m) drifting sediment traps and Th:U deficiency measurements to determine export fluxes of carbon, nitrogen and phosphorus in sinking particles. Simultaneous measurements of nitrate uptake and shallow water nitrification allowed us...
Show moreThe Costa Rica Dome is a picophytoplankton-dominated, open-ocean upwelling system in the Eastern Tropical Pacific that overlies the ocean's largest oxygen minimum zone. To investigate the efficiency of the biological pump in this unique area, we used shallow (90-150 m) drifting sediment traps and Th:U deficiency measurements to determine export fluxes of carbon, nitrogen and phosphorus in sinking particles. Simultaneous measurements of nitrate uptake and shallow water nitrification allowed us to assess the equilibrium balance of new and export production over a monthly timescale. While -ratios (new:total production) were reasonably high (0.36 ± 0.12, mean ± standard deviation), export efficiencies were considerably lower. Sediment traps suggested ratios (export/C-primary production) at 90-100 m ranging from 0.053 to 0.067. ThE-ratios (Th disequilibrium-derived export) ranged from 0.038 to 0.088. C:N and N:P stoichiometries of sinking material were both greater than canonical (Redfield) ratios or measured C:N of suspended particulates, and they increased with depth, suggesting that both nitrogen and phosphorus were preferentially remineralized from sinking particles. Our results are consistent with an ecosystem in which mesozooplankton play a major role in energy transfer to higher trophic levels but are relatively inefficient in mediating vertical carbon flux to depth, leading to an imbalance between new production and sinking flux.
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Date Issued
2016-03-01
Identifier
FSU_pmch_27275035, 10.1093/plankt/fbv097, PMC4889986, 27275035, 27275035, fbv097
Format
Citation
Biomass offsets little or none of permafrost carbon release from soils, streams, and wildfire
Title
Biomass offsets little or none of permafrost carbon release from soils, streams, and wildfire: an expert assessment.
Creator
Abbott, Benjamin W., Jones, Jeremy B., Schuur, Edward A. G., Chapin, F. Stuart, Bowden, William B., Bret-Harte, M. Syndonia, Epstein, Howard E., Flannigan, Michael D., Harms,...
Show moreAbbott, Benjamin W., Jones, Jeremy B., Schuur, Edward A. G., Chapin, F. Stuart, Bowden, William B., Bret-Harte, M. Syndonia, Epstein, Howard E., Flannigan, Michael D., Harms, Tamara K., Hollingsworth, Teresa N., Mack, Michelle C., McGuire, A. David, Natali, Susan M., Rocha, Adrian V., Tank, Suzanne E., Turetsky, Merritt R., Vonk, Jorien E., Wickland, Kimberly P., Aiken, George R., Alexander, Heather D., Amon, Rainer M. W., Benscoter, Brian W., Bergeron, Yves, Bishop, Kevin, Blarquez, Olivier, Bond-Lamberty, Ben, Breen, Amy L., Buffam, Ishi, Cai, Yihua, Carcaillet, Christopher, Carey, Sean K., Chen, Jing M., Chen, Han Y. H., Christensen, Torben R., Cooper, Lee W., Cornelissen, J. Hans C., de Groot, William J., DeLuca, Thomas H., Dorrepaal, Ellen, Fetcher, Ned, Finlay, Jacques C., Forbes, Bruce C., French, Nancy H. F., Gauthier, Sylvie, Girardin, Martin P., Goetz, Scott J., Goldammer, Johann G., Gough, Laura, Grogan, Paul, Guo, Laodong, Higuera, Philip E., Hinzman, Larry, Hu, Feng Sheng, Hugelius, Gustaf, Jafarov, Elchin E., Jandt, Randi, Johnstone, Jill F., Karlsson, Jan, Kasischke, Eric S., Kattner, Gerhard, Kelly, Ryan, Keuper, Frida, Kling, George W., Kortelainen, Pirkko, Kouki, Jari, Kuhry, Peter, Laudon, Hjalmar, Laurion, Isabelle, Macdonald, Robie W., Mann, Paul J., Martikainen, Pertti J., McClelland, James W., Molau, Ulf, Oberbauer, Steven F., Olefeldt, David, Pare, David, Parisien, Marc-Andre, Payette, Serge, Peng, Changhui, Pokrovsky, Oleg S., Rastetter, Edward B., Raymond, Peter A., Raynolds, Martha K., Rein, Guillermo, Reynolds, James F., Robards, Martin, Rogers, Brendan M., Schaedel, Christina, Schaefer, Kevin, Schmidt, Inger K., Shvidenko, Anatoly, Sky, Jasper, Spencer, Robert G. M., Starr, Gregory, Striegl, Robert G., Teisserenc, Roman, Tranvik, Lars J., Virtanen, Tarmo, Welker, Jeffrey M., Zimov, Sergei
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Abstract/Description
As the permafrost region warms, its large organic carbon pool will be increasingly vulnerable to decomposition, combustion, and hydrologic export. Models predict that some portion of this release will be offset by increased production of Arctic and boreal biomass; however, the lack of robust estimates of net carbon balance increases the risk of further overshooting international emissions targets. Precise empirical or model-based assessments of the critical factors driving carbon balance are...
Show moreAs the permafrost region warms, its large organic carbon pool will be increasingly vulnerable to decomposition, combustion, and hydrologic export. Models predict that some portion of this release will be offset by increased production of Arctic and boreal biomass; however, the lack of robust estimates of net carbon balance increases the risk of further overshooting international emissions targets. Precise empirical or model-based assessments of the critical factors driving carbon balance are unlikely in the near future, so to address this gap, we present estimates from 98 permafrost-region experts of the response of biomass, wildfire, and hydrologic carbon flux to climate change. Results suggest that contrary to model projections, total permafrost-region biomass could decrease due to water stress and disturbance, factors that are not adequately incorporated in current models. Assessments indicate that end-of-the-century organic carbon release from Arctic rivers and collapsing coastlines could increase by 75% while carbon loss via burning could increase four-fold. Experts identified water balance, shifts in vegetation community, and permafrost degradation as the key sources of uncertainty in predicting future system response. In combination with previous findings, results suggest the permafrost region will become a carbon source to the atmosphere by 2100 regardless of warming scenario but that 65%-85% of permafrost carbon release can still be avoided if human emissions are actively reduced.
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Date Issued
2016-03
Identifier
FSU_libsubv1_wos_000373401400017, 10.1088/1748-9326/11/3/034014
Format
Citation
Carbon Abatement and Emissions Associated with the Gasification of Walnut Shells for Bioenergy and Biochar Production
Title
Carbon Abatement and Emissions Associated with the Gasification of Walnut Shells for Bioenergy and Biochar Production.
Creator
Pereira, Engil Isadora Pujol, Suddick, Emma C., Six, Johan
Abstract/Description
By converting biomass residue to biochar, we could generate power cleanly and sequester carbon resulting in overall greenhouse gas emissions (GHG) savings when compared to typical fossil fuel usage and waste disposal. We estimated the carbon dioxide (CO2) abatements and emissions associated to the concurrent production of bioenergy and biochar through biomass gasification in an organic walnut farm and processing facility in California, USA. We accounted for (i) avoided-CO2 emissions from...
Show moreBy converting biomass residue to biochar, we could generate power cleanly and sequester carbon resulting in overall greenhouse gas emissions (GHG) savings when compared to typical fossil fuel usage and waste disposal. We estimated the carbon dioxide (CO2) abatements and emissions associated to the concurrent production of bioenergy and biochar through biomass gasification in an organic walnut farm and processing facility in California, USA. We accounted for (i) avoided-CO2 emissions from displaced grid electricity by bioenergy; (ii) CO2 emissions from farm machinery used for soil amendment of biochar; (iii) CO2 sequestered in the soil through stable biochar-C; and (iv) direct CO2 and nitrous oxide (N2O) emissions from soil. The objective of these assessments was to pinpoint where the largest C offsets can be expected in the bioenergy-biochar chain. We found that energy production from gasification resulted in 91.8% of total C offsets, followed by stable biochar-C (8.2% of total C sinks), offsetting a total of 107.7 kg CO2-C eq Mg-1 feedstock. At the field scale, we monitored gas fluxes from soils for 29 months (180 individual observations) following field management and precipitation events in addition to weekly measurements within three growing seasons and two tree dormancy periods. We compared four treatments: control, biochar, compost, and biochar combined with compost. Biochar alone or in combination with compost did not alter total N2O and CO2 emissions from soils, indicating that under the conditions of this study, biochar-prompted C offsets may not be expected from the mitigation of direct soil GHG emissions. However, this study revealed a case where a large environmental benefit was given by the waste-to-bioenergy treatment, addressing farm level challenges such as waste management, renewable energy generation, and C sequestration.
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Date Issued
2016-03-10
Identifier
FSU_libsubv1_wos_000371993000069, 10.1371/journal.pone.0150837
Format
Citation
Carbon-bearing Silicate Melt At Deep Mantle Conditions
Title
Carbon-bearing Silicate Melt At Deep Mantle Conditions.
Creator
Ghosh, Dipta B., Bajgain, Suraj K., Mookherjee, Mainak, Karki, Bijaya B.
Abstract/Description
Knowledge about the incorporation and role of carbon in silicate magmas is crucial for our understanding of the deep mantle processes. CO2 bearing silicate melting and its relevance in the upper mantle regime have been extensively explored. Here we report first-principles molecular dynamics simulations of MgSiO3 melt containing carbon in three distinct oxidation states - CO2, CO, and C at conditions relevant for the whole mantle. Our results show that at low pressures up to 15 GPa, the carbon...
Show moreKnowledge about the incorporation and role of carbon in silicate magmas is crucial for our understanding of the deep mantle processes. CO2 bearing silicate melting and its relevance in the upper mantle regime have been extensively explored. Here we report first-principles molecular dynamics simulations of MgSiO3 melt containing carbon in three distinct oxidation states - CO2, CO, and C at conditions relevant for the whole mantle. Our results show that at low pressures up to 15 GPa, the carbon dioxide speciation is dominated by molecular form and carbonate ions. At higher pressures, the dominant species are silicon-polyhedral bound carbonates, tetrahedral coordination, and polymerized di-carbonates. Our results also indicate that CO2 component remains soluble in the melt at high pressures and the solution is nearly ideal. However, the elemental carbon and CO components show clustering of carbon atoms in the melt at high pressures, hinting towards possible exsolution of carbon from silicate melt at reduced oxygen contents. Although carbon lowers the melt density, the effect is modest at high pressures. Hence, it is likely that silicate melt above and below the mantle transition zone, and atop the core-mantle boundary could efficiently sequester significant amounts of carbon without being gravitationally unstable.
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Date Issued
2017-04-12
Identifier
FSU_libsubv1_wos_000399186000012, 10.1038/s41598-017-00918-x
Format
Citation
Changes in bacterioplankton community structure after exposure to oil and dispersants in the Northeastern Gulf of Mexico
Title
Changes in bacterioplankton community structure after exposure to oil and dispersants in the Northeastern Gulf of Mexico.
Creator
Deep-C Consortium, Gulf of Mexico Research Institute, University of West Florida, The Center for Environmental Diagnostics & Bioremediation, Houghton, Katelyn, Hutcheson,...
Show moreDeep-C Consortium, Gulf of Mexico Research Institute, University of West Florida, The Center for Environmental Diagnostics & Bioremediation, Houghton, Katelyn, Hutcheson, Josette, Tominack, Sarah, Moss, Joe, Reisenfeld, Christian, Snyder, Richard, Jeffrey, Wade
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Date Issued
2013-02
Identifier
FSU_HPUA_2015_038_AllHandsPoster_012
Format
Document (PDF)
Changes in the Redox State of Sediments Following the 2010 BP Blowout
Title
Changes in the Redox State of Sediments Following the 2010 BP Blowout.
Creator
Deep-C Consortium, Eckerd College, University of South Florida, Hastings, David, Brooks, Gregg, Larson, Rebekka, Hammaker, Shannon, Roeder, Tara, Schwing, Patrick, Romero,...
Show moreDeep-C Consortium, Eckerd College, University of South Florida, Hastings, David, Brooks, Gregg, Larson, Rebekka, Hammaker, Shannon, Roeder, Tara, Schwing, Patrick, Romero, Isabel, Hollander, David
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Date Issued
2013-09-10
Identifier
FSU_HPUA_2015_038_AllHandsSept_010
Format
Document (PDF)
Characterization of the Florida Panhandle Shelf
Title
Characterization of the Florida Panhandle Shelf.
Creator
Deep-C Consortium, Gulf of Mexico Research Initiative, Florida State University, University of South Florida, University of West Florida, Valdosta State University, Snyder,...
Show moreDeep-C Consortium, Gulf of Mexico Research Initiative, Florida State University, University of South Florida, University of West Florida, Valdosta State University, Snyder, Richard, Jeffrey, Wade
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Date Issued
2013-09-11
Identifier
FSU_HPUA_2015_038_AllHandsSept_022
Format
Document (PDF)
Characterization of the Water-Soluble and Interfacially Active Species from the Deepwater Horizon Crude by Electrospray lonization FT-ICR Mass Spectrometry
Title
Characterization of the Water-Soluble and Interfacially Active Species from the Deepwater Horizon Crude by Electrospray lonization FT-ICR Mass Spectrometry.
Creator
Deep-C Consortium, National High Magnetic Field Laboratory, Jarvis, Jacqueline M., Robbins, Winston K., Marshall, Alan G., Rodgers, Ryan P.
Date Issued
2013-02
Identifier
FSU_HPUA_2015_038_AllHandsPoster_015
Format
Document (PDF)
Characterizing the onset and demise of the Indian summer monsoon
Title
Characterizing the onset and demise of the Indian summer monsoon.
Creator
Noska, Ryne, Misra, Vasubandhu
Abstract/Description
An objective index of the onset and demise of the Indian summer monsoon (ISM) is introduced. This index has the advantage of simplicity by using only one variable, which is the spatially averaged all-India rainfall, a reliably observed quantity for more than a century. The proposed onset index is shown to be insensitive to all historic false onsets. By definition, now the seasonal mean rainfall anomalies become a function of variations in onset and demise dates, rendering their monitoring to...
Show moreAn objective index of the onset and demise of the Indian summer monsoon (ISM) is introduced. This index has the advantage of simplicity by using only one variable, which is the spatially averaged all-India rainfall, a reliably observed quantity for more than a century. The proposed onset index is shown to be insensitive to all historic false onsets. By definition, now the seasonal mean rainfall anomalies become a function of variations in onset and demise dates, rendering their monitoring to be very meaningful. This new index provides a comprehensive representation of the seasonal evolution of the ISM by capturing the corresponding changes in large-scale dynamic and thermodynamic variables. We also show that the interannual variability of the onset date of the ISM is associated with El Nino-Southern Oscillation (ENSO) with early (late) onsets preceded by cold (warm) ENSO.
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Date Issued
2016-05-16
Identifier
FSU_libsubv1_wos_000378339200057, 10.1002/2016GL068409
Format
Citation
Characterizing the Upper Ocean Response to Hurricanes Isaac (slow) and Ivan (fast) Over the DeSoto Canyon
Title
Characterizing the Upper Ocean Response to Hurricanes Isaac (slow) and Ivan (fast) Over the DeSoto Canyon.
Creator
Deep-C Consortium, National Oceanic and Atmospheric Administration, RSMAS, Shay, L. (Nick), Jaimes, B., Brewster, J., Schuster, R., Halliwell, G., Powell, M., Teague, W.
Date Issued
2013-09-10
Identifier
FSU_HPUA_2015_038_AllHandsSept_020
Format
Document (PDF)
Chronic, Anthropogenic Hydrocarbon Releases in the Gulf of Mexico
Title
Chronic, Anthropogenic Hydrocarbon Releases in the Gulf of Mexico.
Creator
Deep-C Consortium, Center for Ocean-Atmospheric Prediction Studies, Florida State University, Daneshgar Asl, Samira, Amos, John, Woods, Paul, Garcia-Pineda, Oscar, MacDonald,...
Show moreDeep-C Consortium, Center for Ocean-Atmospheric Prediction Studies, Florida State University, Daneshgar Asl, Samira, Amos, John, Woods, Paul, Garcia-Pineda, Oscar, MacDonald, Ian R.
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Date Issued
2013-02
Identifier
FSU_HPUA_2015_038_AllHandsPoster_007
Format
Document (PDF)
Chronic, Anthropogenic Hydrocarbon Releases in the Gulf of Mexico (2)
Title
Chronic, Anthropogenic Hydrocarbon Releases in the Gulf of Mexico (2).
Creator
Deep-C Consortium, Center for Ocean-Atmospheric Prediction Studies, Florida State University, Daneshgar Asl, Samira, Amos, John, Woods, Paul, Garcia-Pineda, Oscar, MacDonald,...
Show moreDeep-C Consortium, Center for Ocean-Atmospheric Prediction Studies, Florida State University, Daneshgar Asl, Samira, Amos, John, Woods, Paul, Garcia-Pineda, Oscar, MacDonald, Ian R.
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Date Issued
2013-02
Identifier
FSU_HPUA_2015_038_AllHandsPoster_006
Format
Document (PDF)
Comparison Of The Ocean Surface Vector Winds From Atmospheric Reanalysis And Scatterometer-based Wind Products Over The Nordic Seas And The Northern North Atlantic And Their Application For Ocean Modeling
Title
Comparison Of The Ocean Surface Vector Winds From Atmospheric Reanalysis And Scatterometer-based Wind Products Over The Nordic Seas And The Northern North Atlantic And Their Application For Ocean Modeling.
Creator
Dukhovskoy, Dmitry S., Bourassa, Mark A., Petersen, Guorun Nina, Steffen, John
Abstract/Description
Ocean surface vector wind fields from reanalysis data sets and scatterometer-derived gridded products are analyzed over the Nordic Seas and the northern North Atlantic for the time period from 2000 to 2009. The data sets include the National Center for Environmental Prediction Reanalysis 2 (NCEPR2), Climate Forecast System Reanalysis (CFSR), Arctic System Reanalysis (ASR), Cross-Calibrated Multiplatform (CCMP) wind product version 1.1 and recently released version 2.0, and QuikSCAT. The goal...
Show moreOcean surface vector wind fields from reanalysis data sets and scatterometer-derived gridded products are analyzed over the Nordic Seas and the northern North Atlantic for the time period from 2000 to 2009. The data sets include the National Center for Environmental Prediction Reanalysis 2 (NCEPR2), Climate Forecast System Reanalysis (CFSR), Arctic System Reanalysis (ASR), Cross-Calibrated Multiplatform (CCMP) wind product version 1.1 and recently released version 2.0, and QuikSCAT. The goal of the study is to assess discrepancies across the wind vector fields in the data sets and demonstrate possible implications of these differences for ocean modeling. Large-scale and mesoscale characteristics of winds are compared at interannual, seasonal, and synoptic timescales. A cyclone tracking methodology is developed and applied to the wind fields to compare cyclone characteristics in the data sets. Additionally, the winds are evaluated against observations collected from meteorological buoys deployed in the Iceland and Irminger Seas. The agreement among the wind fields is better for longer time and larger spatial scales. The discrepancies are clearly apparent for synoptic timescales and mesoscales. CCMP, ASR, and CFSR show the closest overall agreement with each other. Substantial biases are found in the NCEPR2 winds. Numerical sensitivity experiments are conducted with a coupled ice-ocean model forced by different wind fields. The experiments demonstrate differences in the net surface heat fluxes during storms. In the experiment forced by NCEPR2 winds, there are discrepancies in the large-scale wind-driven ocean dynamics compared to the other experiments.
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Date Issued
2017-03
Identifier
FSU_libsubv1_wos_000400678900018, 10.1002/2016JC012453
Format
Citation
Contribution of Monthly and Regional Rainfall to the Strength of Indian Summer Monsoon
Title
Contribution of Monthly and Regional Rainfall to the Strength of Indian Summer Monsoon.
Creator
Zheng, Yangxing, Ali, M. M., Bourassa, Mark A.
Abstract/Description
Indian summer monsoon rainfall (ISMR; June September) has both temporal and spatial variability causing floods and droughts in different seasons and locations, leading to a strong or weak monsoon. Here, the authors present the contribution of all-India monthly, seasonal, and regional rainfall to the ISMR, with an emphasis on the strong and weak monsoons. Here, regional rainfall is restricted to the seasonal rainfall over four regions defined by the India Meteorological Department (IMD)...
Show moreIndian summer monsoon rainfall (ISMR; June September) has both temporal and spatial variability causing floods and droughts in different seasons and locations, leading to a strong or weak monsoon. Here, the authors present the contribution of all-India monthly, seasonal, and regional rainfall to the ISMR, with an emphasis on the strong and weak monsoons. Here, regional rainfall is restricted to the seasonal rainfall over four regions defined by the India Meteorological Department (IMD) primarily for the purpose of forecasting regional rainfall: northwest India (NWI), northeast India (NEI), central India (CI), and south peninsula India (SPIN). In this study, two rainfall datasets provided by IMD are used: 1) all-India monthly and seasonal (June September) rainfall series for the entire Indian subcontinent as well as seasonal rainfall series for the four homogeneous regions for the period 1901-2013 and 2) the latest daily gridded rainfall data for the period 1951-2014, which is used for assessment at the extent to which the four regions are appropriate for the intended purpose. Rainfall during July August contributes the most to the total seasonal rainfall, regardless of whether it is a strong or weak monsoon. Although NEI has the maximum area-weighted rainfall, its contribution is the least toward determining a strong or weak monsoon. It is the rainfall in the remaining three regions (NWI, CI, and SPIN) that controls whether an ISMR is strong or weak. Compared to monthly rainfall, regional rainfall dominates the strong or weak rainfall periods.
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Date Issued
2016-09
Identifier
FSU_libsubv1_wos_000383923300001, 10.1175/MWR-D-15-0318.1
Format
Citation
Crevasse Splays Versus Avulsions
Title
Crevasse Splays Versus Avulsions: A Recipe For Land Building With Levee Breaches.
Creator
Nienhuis, Jaap H., Tornqvist, Torbjorn E., Esposito, Christopher R.
Abstract/Description
Natural-levee breaches can not only initiate an avulsion but also, under the right circumstances, lead to crevasse splay formation and overbank sedimentation. The formative conditions for crevasse splays are not well understood, yet such river sediment diversions form an integral part of billion-dollar coastal restoration projects. Here we use Delft3D to investigate the influence of vegetation and soil consolidation on the evolution of a natural-levee breach. Model simulations show that...
Show moreNatural-levee breaches can not only initiate an avulsion but also, under the right circumstances, lead to crevasse splay formation and overbank sedimentation. The formative conditions for crevasse splays are not well understood, yet such river sediment diversions form an integral part of billion-dollar coastal restoration projects. Here we use Delft3D to investigate the influence of vegetation and soil consolidation on the evolution of a natural-levee breach. Model simulations show that crevasse splays heal because floodplain aggradation reduces the water surface slope, decreasing water discharge into the flood basin. Easily erodible and unvegetated floodplains increase the likelihood for channel avulsions. Denser vegetation and less potential for soil consolidation result in small crevasse splays that are not only efficient sediment traps but also short-lived. Successful crevasse splays that generate the largest land area gain for the imported sediment require a delicate balance between water and sediment discharge, vegetation root strength, and soil consolidation.
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Date Issued
2018-05-16
Identifier
FSU_libsubv1_wos_000434111700035, 10.1029/2018GL077933
Format
Citation
Decadal Surface Temperature Trends In India Based On A New High-resolution Data Set
Title
Decadal Surface Temperature Trends In India Based On A New High-resolution Data Set.
Creator
Ross, Robert S., Krishnamurti, T. N., Pattnaik, Sandeep, Pai, D. S.
Abstract/Description
A new comprehensive surface temperature data set for India is used to document changes in Indian temperature over seven decades, in order to examine the patterns and possible effects of global warming. The data set is subdivided into pre-monsoon, monsoon, and post-monsoon categories in order to study the temperature patterns in each of these periods. When the decade means in maximum, minimum and daily mean temperature for the 2000s are compared to those of the 1950s, a consistent pattern of...
Show moreA new comprehensive surface temperature data set for India is used to document changes in Indian temperature over seven decades, in order to examine the patterns and possible effects of global warming. The data set is subdivided into pre-monsoon, monsoon, and post-monsoon categories in order to study the temperature patterns in each of these periods. When the decade means in maximum, minimum and daily mean temperature for the 2000s are compared to those of the 1950s, a consistent pattern of warming is found over northwestern and southern India, and a pattern of cooling is seen in a broad zone anchored over northeastern India and extending southwestward across central India. These patterns are explained by the presence of a large region of anthropogenic brown haze over India and adjacent ocean regions. These aerosols absorb solar radiation, leading to warming of the haze layer over northeastern and central India and to cooling of the surface air beneath. The heated air rises and then sinks to the north and south of the haze region over northwestern and southern India, warming the air by compression as it sinks in those regions. The possible impact of these temperature patterns on Indian agriculture is considered.
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Date Issued
2018-05-10
Identifier
FSU_libsubv1_wos_000431763100004, 10.1038/s41598-018-25347-2
Format
Citation
Decadal Variability Of The Meridional Geostrophic Transport In The Upper Tropical North Pacific Ocean
Title
Decadal Variability Of The Meridional Geostrophic Transport In The Upper Tropical North Pacific Ocean.
Creator
Zhou, Hui, Yuan, Dongliang, Yang, Lina, Li, Xiang, Dewar, William
Abstract/Description
The meridional geostrophic transport (MGT) in the interior tropical North Pacific Ocean is estimated based on global ocean heat and salt content data. The decadal variations of the zonally and vertically integrated MGT in the tropical North Pacific Ocean are found to precede the Pacific decadal oscillation (PDO) by 1-3 years. The dynamics of the MGT are analyzed based on Sverdrup theory. It is found that the total meridional transport variability (MGT plus Ekman) is dominated by the MGT...
Show moreThe meridional geostrophic transport (MGT) in the interior tropical North Pacific Ocean is estimated based on global ocean heat and salt content data. The decadal variations of the zonally and vertically integrated MGT in the tropical North Pacific Ocean are found to precede the Pacific decadal oscillation (PDO) by 1-3 years. The dynamics of the MGT are analyzed based on Sverdrup theory. It is found that the total meridional transport variability (MGT plus Ekman) is dominated by the MGT variability having positive correlations with the PDO index. The Sverdrup transports differ from the total meridional transport significantly and have insignificant correlations with PDO index, suggesting that the MGT variability is not controlled by the Sverdrup dynamics. In comparison, the simulated meridional transport variability in the models from phase 5 of the Coupled Model Intercomparison Project (CMIP5) and the Ocean General Circulation Model for the Earth Simulator are dominated by the Sverdrup transports, having insignificant correlations with the simulated PDO indices. The comparison suggests that the non-Sverdrup component in the MGT is important for the predictability of PDO and that significant deficiencies exist in these models in simulating a realistic structure of the tropical ocean gyre variability and predicting the decadal climate variations associated with it.
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Date Issued
2018-08-01
Identifier
FSU_libsubv1_wos_000438848800007, 10.1175/JCLI-D-17-0639.1
Format
Citation
Deep Currents Near Steep Bathymetry from a Numerical Simulation of DeSoto Canyon
Title
Deep Currents Near Steep Bathymetry from a Numerical Simulation of DeSoto Canyon.
Creator
Deep-C Consortium, Coupled Ocean-Atmosphere Mesoscale Prediction System, Morey, Steve, Dukhovskoy, Dmitry, Chassignet, Eric
Date Issued
2013-02
Identifier
FSU_HPUA_2015_038_AllHandsPoster_022
Format
Document (PDF)
Deep Oceanic Response to Hurricane Forcing In DeSoto Canyon Region
Title
Deep Oceanic Response to Hurricane Forcing In DeSoto Canyon Region.
Creator
Deep-C Consortium, RSMAS, National Oceanic Atmospheric Administration, Shay, L. K., Haunes, B., Schuster, R., Teague, Bill, Halliwell, George
Date Issued
2012-08-21, 2012-08-22
Identifier
FSU_HPUA_2015_038_AllHandsAug_020
Format
Document (PDF)
Deep-C DeSoto Canyon Moorings: Overview of Measurements an Preliminary Results
Title
Deep-C DeSoto Canyon Moorings: Overview of Measurements an Preliminary Results.
Creator
Deep-C Consortium, SAIC, Bureau of Ocean Energy Management, Hamilton, Peter, Speer, Kevin, Wienders, Nicolas, Singer, James
Date Issued
2013-09-10
Identifier
FSU_HPUA_2015_038_AllHandsSept_009
Format
Document (PDF)
Deep-C Ecological Pathways
Title
Deep-C Ecological Pathways.
Creator
Deep-C Consortium
Date Issued
2011-11-01
Identifier
FSU_HPUA_2015_038_Kickoff_002
Format
Document (PDF)
Defying Dissolution
Title
Defying Dissolution: Discovery Of Deep-sea Scleractinian Coral Reefs In The North Pacific.
Creator
Baco, Amy R., Morgan, Nicole, Roark, E. Brendan, Silva, Mauricio, Shamberger, Kathryn E. F., Miller, Kelci
Abstract/Description
Deep-sea scleractinian coral reefs are protected ecologically and biologically significant areas that support global fisheries. The absence of observations of deep-sea scleractinian reefs in the Central and Northeast Pacific, combined with the shallow aragonite saturation horizon (ASH) and high carbonate dissolution rates there, fueled the hypothesis that reef formation in the North Pacific was improbable. Despite this, we report the discovery of live scleractinian reefs on six seamounts of...
Show moreDeep-sea scleractinian coral reefs are protected ecologically and biologically significant areas that support global fisheries. The absence of observations of deep-sea scleractinian reefs in the Central and Northeast Pacific, combined with the shallow aragonite saturation horizon (ASH) and high carbonate dissolution rates there, fueled the hypothesis that reef formation in the North Pacific was improbable. Despite this, we report the discovery of live scleractinian reefs on six seamounts of the Northwestern Hawaiian Islands and Emperor Seamount Chain at depths of 535-732 m and aragonite saturation state (Omega(arag)) values of 0.71-1.33. Although the ASH becomes deeper moving northwest along the chains, the depth distribution of the reefs becomes shallower, suggesting the ASH is having little influence on their distribution. Higher chlorophyll moving to the northwest may partially explain the geographic distribution of the reefs. Principle Components Analysis suggests that currents are also an important factor in their distribution, but neither chlorophyll nor the available current data can explain the unexpected depth distribution. Further environmental data is needed to elucidate the reason for the distribution of these reefs. The discovery of reef-forming scleractinians in this region is of concern because a number of the sites occur on seamounts with active trawl fisheries.
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Date Issued
2017-07-14
Identifier
FSU_libsubv1_wos_000405464200073, 10.1038/s41598-017-05492-w
Format
Citation
Dehydration of chlorite explains anomalously high electrical conductivity in the mantle wedges
Title
Dehydration of chlorite explains anomalously high electrical conductivity in the mantle wedges.
Creator
Manthilake, Geeth, Bolfan-Casanova, Nathalie, Novella, Davide, Mookherjee, Mainak, Andrault, Denis
Abstract/Description
Mantle wedge regions in subduction zone settings show anomalously high electrical conductivity (similar to 1 S/m) that has often been attributed to the presence of aqueous fluids released by slab dehydration. Laboratory-based measurements of the electrical conductivity of hydrous phases and aqueous fluids are significantly lower and cannot readily explain the geophysically observed anomalously high electrical conductivity. The released aqueous fluid also rehydrates the mantle wedge and...
Show moreMantle wedge regions in subduction zone settings show anomalously high electrical conductivity (similar to 1 S/m) that has often been attributed to the presence of aqueous fluids released by slab dehydration. Laboratory-based measurements of the electrical conductivity of hydrous phases and aqueous fluids are significantly lower and cannot readily explain the geophysically observed anomalously high electrical conductivity. The released aqueous fluid also rehydrates the mantle wedge and stabilizes a suite of hydrous phases, including serpentine and chlorite. In this present study, we have measured the electrical conductivity of a natural chlorite at pressures and temperatures relevant for the subduction zone setting. In our experiment, we observe two distinct conductivity enhancements when chlorite is heated to temperatures beyond its thermodynamic stability field. The initial increase in electrical conductivity to similar to 3 x 10(-3) S/m can be attributed to chlorite dehydration and the release of aqueous fluids. This is followed by a unique, subsequent enhancement of electrical conductivity of up to 7 x 10(-1) S/m. This is related to the growth of an interconnected network of a highly conductive and chemically impure magnetite mineral phase. Thus, the dehydration of chlorite and associated processes are likely to be crucial in explaining the anomalously high electrical conductivity observed in mantle wedges. Chlorite dehydration in the mantle wedge provides an additional source of aqueous fluid above the slab and could also be responsible for the fixed depth (120 +/- 40 km) of melting at the top of the subducting slab beneath the subduction-related volcanic arc front.
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Date Issued
2016-05
Identifier
FSU_libsubv1_wos_000380073000012, 10.1126/sciadv.1501631
Format
Citation
Dehydration of chlorite explains anomalously high electrical conductivity in the mantle wedges.
Title
Dehydration of chlorite explains anomalously high electrical conductivity in the mantle wedges.
Creator
Manthilake, Geeth, Bolfan-Casanova, Nathalie, Novella, Davide, Mookherjee, Mainak, Andrault, Denis
Abstract/Description
Mantle wedge regions in subduction zone settings show anomalously high electrical conductivity (~1 S/m) that has often been attributed to the presence of aqueous fluids released by slab dehydration. Laboratory-based measurements of the electrical conductivity of hydrous phases and aqueous fluids are significantly lower and cannot readily explain the geophysically observed anomalously high electrical conductivity. The released aqueous fluid also rehydrates the mantle wedge and stabilizes a...
Show moreMantle wedge regions in subduction zone settings show anomalously high electrical conductivity (~1 S/m) that has often been attributed to the presence of aqueous fluids released by slab dehydration. Laboratory-based measurements of the electrical conductivity of hydrous phases and aqueous fluids are significantly lower and cannot readily explain the geophysically observed anomalously high electrical conductivity. The released aqueous fluid also rehydrates the mantle wedge and stabilizes a suite of hydrous phases, including serpentine and chlorite. In this present study, we have measured the electrical conductivity of a natural chlorite at pressures and temperatures relevant for the subduction zone setting. In our experiment, we observe two distinct conductivity enhancements when chlorite is heated to temperatures beyond its thermodynamic stability field. The initial increase in electrical conductivity to ~3 × 10(-3) S/m can be attributed to chlorite dehydration and the release of aqueous fluids. This is followed by a unique, subsequent enhancement of electrical conductivity of up to 7 × 10(-1) S/m. This is related to the growth of an interconnected network of a highly conductive and chemically impure magnetite mineral phase. Thus, the dehydration of chlorite and associated processes are likely to be crucial in explaining the anomalously high electrical conductivity observed in mantle wedges. Chlorite dehydration in the mantle wedge provides an additional source of aqueous fluid above the slab and could also be responsible for the fixed depth (120 ± 40 km) of melting at the top of the subducting slab beneath the subduction-related volcanic arc front.
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Date Issued
2016-05-06
Identifier
FSU_pmch_27386526, 10.1126/sciadv.1501631, PMC4928900, 27386526, 27386526, 1501631
Format
Citation
Demersal fish assemblages associated with Desoto Canyon and the continental slope of the eastern Gulf of Mexico
Title
Demersal fish assemblages associated with Desoto Canyon and the continental slope of the eastern Gulf of Mexico.
Creator
Deep-C Consortium, Florida State University, University of North Florida, Florida International University, Savannah State University, State of Florida Institute of Oceanography...
Show moreDeep-C Consortium, Florida State University, University of North Florida, Florida International University, Savannah State University, State of Florida Institute of Oceanography, Gulf of Mexico Research Institute, Grubbs, Dean, Coleman, Felicia, Koenig, Chris, Gelsleichter, Jim, Heithaus, Mike, Cotton, Chip
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Date Issued
2012-08-21, 2012-08-22
Identifier
FSU_HPUA_2015_038_AllHandsAug_009
Format
Document (PDF)
Deposition and Degradation of DWH Oil in Gulf Sediments
Title
Deposition and Degradation of DWH Oil in Gulf Sediments.
Creator
Deep-C Consortium, Gulf of Mexico Research Initiative, Florida State University, Georgia Institute of Technology, Eckerd College, University of South Florida, Huettel, Markus,...
Show moreDeep-C Consortium, Gulf of Mexico Research Initiative, Florida State University, Georgia Institute of Technology, Eckerd College, University of South Florida, Huettel, Markus, Kostka, Joel, Hastings, David, Green, Stefan, Prakash, Om, Hagan, Chris, Kaba, John, Wells, Brian, Ruddy, Brian, Dudley, Stacia, Smith, Matt, Okolovitch, Curtis, Overholt, Will, Canion, Andy, Delgardio, Jonathan, Norton, Nikita
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Date Issued
2013-09-10
Identifier
FSU_HPUA_2015_038_AllHandsSept_012
Format
Document (PDF)
Depth-mediated differences in trophic ecology and mercury contomination in six species of sharks in DeSoto Canyon
Title
Depth-mediated differences in trophic ecology and mercury contomination in six species of sharks in DeSoto Canyon.
Creator
Deep-C Consortium, Florida State University, Imhoff, Johanna L, Grubbs, R. Dean
Date Issued
2013-02
Identifier
FSU_HPUA_2015_038_AllHandsPoster_014
Format
Document (PDF)

Pages