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Sample records for atlantic killifish fundulus

  1. Genetic linkage map and comparative genome analysis for the estuarine Atlantic killifish (Fundulus heteroclitus)

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    U.S. Environmental Protection Agency — Genetic linkage maps are valuable tools in evolutionary biology; however, their availability for wild populations is extremely limited. Fundulus heteroclitus...

  2. Evolution of tolerance to PCBs and susceptibility to a bacterial pathogen (Vibrio harveyi) in Atlantic killifish (Fundulus heteroclitus) from New Bedford (MA, USA) harbor

    Energy Technology Data Exchange (ETDEWEB)

    Nacci, Diane [US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Atlantic Ecology Division, Narragansett, RI (United States)], E-mail: nacci.diane@epa.gov; Huber, Marina [US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Atlantic Ecology Division, Narragansett, RI (United States)], E-mail: akualtzin@yahoo.com; Champlin, Denise [US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Atlantic Ecology Division, Narragansett, RI (United States)], E-mail: champlin.denise@epa.gov; Jayaraman, Saro [US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Atlantic Ecology Division, Narragansett, RI (United States)], E-mail: jayaraman.saro@epa.gov; Cohen, Sarah [San Francisco State University, Department of Biology, Romberg Tiburon Center, San Francisco, CA (United States)], E-mail: sarahcoh@sfsu.edu; Gauger, Eric [University of Rhode Island, Department of Fisheries, Aquaculture, and Veterinary Sciences, Kingston, RI (United States)], E-mail: ejgauger@yahoo.com; Fong, Allison [University of Rhode Island, Department of Fisheries, Aquaculture, and Veterinary Sciences, Kingston, RI (United States)], E-mail: fonga@hawaii.edu; Gomez-Chiarri, Marta [University of Rhode Island, Department of Fisheries, Aquaculture, and Veterinary Sciences, Kingston, RI (United States)], E-mail: gomezchi@uri.edu

    2009-03-15

    A population of the non-migratory estuarine fish Fundulus heteroclitus (Atlantic killifish) resident to New Bedford (NB), Massachusetts, USA, an urban harbor highly contaminated with polychlorinated biphenyls (PCBs), demonstrates recently evolved tolerance to some aspects of PCB toxicity. PCB toxicology, ecological theory, and some precedence supported expectations of increased susceptibility to pathogens in NB killifish. However, laboratory bacterial challenges of the marine pathogen Vibrio harveyi to wild fish throughout the reproductive season and to their mature laboratory-raised progeny demonstrated comparable survival by NB and reference killifish, and improved survival by NB males. These results are inconsistent with hypothesized trade-offs of adaptation, and suggest that evolved tolerance in NB killifish may include mechanisms that minimize the immunosuppressive effects of PCBs. Compensatory strategies of populations persisting in highly contaminated environments provide a unique perspective for understanding the long-term ecological effects of toxic chemicals. - Killifish resident to a highly PCB-contaminated estuary survive pathogenic bacterial challenges well, suggesting their tolerance to PCB immunosuppression.

  3. Effects of benzo[a]pyrene on mitochondrial and nuclear DNA damage in Atlantic killifish (Fundulus heteroclitus) from a creosote-contaminated and reference site

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    Jung, Dawoon; Cho, Youngeun [Nicholas School of the Environment, Duke University, Durham, NC 27708 (United States); Collins, Leonard B.; Swenberg, James A. [Center for Environmental Health and Susceptibility, Gillings School of Global Public Health, University of North Carolina-Chapel Hill, Chapel Hill, NC 27599 (United States); Di Giulio, Richard T., E-mail: richd@duke.edu [Nicholas School of the Environment, Duke University, Durham, NC 27708 (United States)

    2009-10-19

    Benzo[a]pyrene (BaP) is a known genotoxicant that affects both mitochondrial and nuclear DNA (mtDNA, nDNA). Here, we examined mtDNA and nDNA damage in the Atlantic killifish (Fundulus heteroclitus) from a highly contaminated Superfund site (Elizabeth River, VA, USA) and from a reference site (King's Creek, VA, USA) that were dosed with 10 mg/kg BaP. Using the long amplicon quantitative PCR technique, we observed similar increases in mitochondrial and nuclear DNA damage in King's Creek fish treated with BaP. Killifish from the Elizabeth River showed high levels of basal nDNA and mtDNA damage compared to fish from the reference site, but the level of damage induced due to BaP treatment was much lower in Elizabeth River killifish compared to King's Creek fish. Laboratory-reared offspring from both populations showed increased BaP-induced damage in mtDNA, relative to nDNA. Similar to the adult experiment, the Elizabeth River larvae had higher levels of basal DNA damage than those from the reference site, but were less impacted by BaP exposure. Measurements of oxidative DNA damage (8-oxo-deoxyguanine by LC-MS/MS) showed no differences among treatment groups, suggesting that the majority of DNA damage is from covalent binding of BaP metabolites to DNA. This study shows for the first time that mitochondria can be an important target of BaP toxicity in fish, indicating that BaP exposures could have important energetic consequences. Results also suggest that multi-generational exposures in the wild may lead to adaptations that dampen DNA damage arising from BaP exposure.

  4. AHR-related activities in a creosote-adapted population of adult atlantic killifish, Fundulus heteroclitus, two decades post-EPA superfund status at the Atlantic Wood Site, Portsmouth, VA USA.

    Science.gov (United States)

    Wojdylo, Josephine V; Vogelbein, Wolfgang; Bain, Lisa J; Rice, Charles D

    2016-08-01

    Atlantic killifish, Fundulus heteroclitus, are adapted to creosote-based PAHs at the US EPA Superfund site known as Atlantic Wood (AW) on the southern branch of the Elizabeth River, VA USA. Subsequent to the discovery of the AW population in the early 1990s, these fish were shown to be recalcitrant to CYP1A induction by PAHs under experimental conditions, and even to the time of this study, killifish embryos collected from the AW site are resistant to developmental deformities typically associated with exposure to PAHs in reference fish. Historically, however, 90 +% of the adult killifish at this site have proliferative hepatic lesions including cancer of varying severity. Several PAHs at this site are known to be ligands for the aryl hydrocarbon receptor (AHR). In this study, AHR-related activities in AW fish collected between 2011 and 2013 were re-examined nearly 2 decades after first discovery. This study shows that CYP1A mRNA expression is three-fold higher in intestines of AW killifish compared to a reference population. Using immunohistochemistry, CYP1A staining in intestines was uniformly positive compared to negative staining in reference fish. Livers of AW killifish were examined by IHC to show that CYP1A and AHR2 protein expression reflect lesions-specific patterns, probably representing differences in intrinsic cellular physiology of the spectrum of proliferative lesions comprising the hepatocarcinogenic process. We also found that COX2 mRNA expression levels were higher in AW fish livers compared to those in the reference population, suggesting a state of chronic inflammation. Overall, these findings suggest that adult AW fish are responsive to AHR signaling, and do express CYP1A and AHR2 proteins in intestines at a level above what was observed in the reference population. PMID:27262937

  5. Methylmercury teratogenesis in the killifish, Fundulus heteroclitus.

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    Weis, P; Weis, J S

    1977-12-01

    Exposure of developing eggs of the killifish, Fundulus heteroclitus, to 0.03 or 0.04 mg/l of methylmercuric chloride resulted in a variety of abnormalities. Percentage of axis formation was reduced somewhat, and many embryos developed cyclopia or intermediate conditions leading to cyclopia, reflecting interference with induction of the forebrain. Defects in the cardiovascular system also appeared in the form of failure of the heart to differentiate properly into chambers. The heart was a thin, feebly beating tube, incapable of causing the blood to circulate. Other tissues, however, continued developing fairly normally, and embryos showed spontaneous movement comparable to controls. Embryos with severe cardiovascular or optic defects did not hatch. Upon hatching, some embryos which had previously appeared normal were found to have skeletal malformations in the form of vertebral bends or the inability to uncurl from the position which they had while still inside the chorion. Exposure to the toxicant for shorter periods of time (6, 12, or 24 hours) reduced the incidence of abnormalities. The second day of development was found to be the most sensitive period. PMID:413205

  6. Transcriptomic assessment of resistance to effects of an aryl hydrocarbon receptor (AHR agonist in embryos of Atlantic killifish (Fundulus heteroclitus from a marine Superfund site

    Directory of Open Access Journals (Sweden)

    Franks Diana G

    2011-05-01

    Full Text Available Abstract Background Populations of Atlantic killifish (Fundulus heteroclitus have evolved resistance to the embryotoxic effects of polychlorinated biphenyls (PCBs and other halogenated and nonhalogenated aromatic hydrocarbons that act through an aryl hydrocarbon receptor (AHR-dependent signaling pathway. The resistance is accompanied by reduced sensitivity to induction of cytochrome P450 1A (CYP1A, a widely used biomarker of aromatic hydrocarbon exposure and effect, but whether the reduced sensitivity is specific to CYP1A or reflects a genome-wide reduction in responsiveness to all AHR-mediated changes in gene expression is unknown. We compared gene expression profiles and the response to 3,3',4,4',5-pentachlorobiphenyl (PCB-126 exposure in embryos (5 and 10 dpf and larvae (15 dpf from F. heteroclitus populations inhabiting the New Bedford Harbor, Massachusetts (NBH Superfund site (PCB-resistant and a reference site, Scorton Creek, Massachusetts (SC; PCB-sensitive. Results Analysis using a 7,000-gene cDNA array revealed striking differences in responsiveness to PCB-126 between the populations; the differences occur at all three stages examined. There was a sizeable set of PCB-responsive genes in the sensitive SC population, a much smaller set of PCB-responsive genes in NBH fish, and few similarities in PCB-responsive genes between the two populations. Most of the array results were confirmed, and additional PCB-regulated genes identified, by RNA-Seq (deep pyrosequencing. Conclusions The results suggest that NBH fish possess a gene regulatory defect that is not specific to one target gene such as CYP1A but rather lies in a regulatory pathway that controls the transcriptional response of multiple genes to PCB exposure. The results are consistent with genome-wide disruption of AHR-dependent signaling in NBH fish.

  7. Genetic basis for evolved tolerance to dioxin-like pollutants in wild Atlantic killifish: more than the aryl hydrocarbon receptor

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    Atlantic killifish (Fundulus heteroclitus) resident to some US urban and industrialized estuaries demonstrate recently evolved and extreme tolerance to toxic dioxin-like compounds (DLCs). Here we provide an unusually comprehensive accounting (69%) through Quantitative Trait Locus (QTL) analysis of ...

  8. A novel aquaporin 3 in killifish (Fundulus heteroclitus) is not an arsenic channel.

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    Jung, Dawoon; MacIver, Bryce; Jackson, Brian P; Barnaby, Roxanna; Sato, J Denry; Zeidel, Mark L; Shaw, Joseph R; Stanton, Bruce A

    2012-05-01

    The Atlantic killifish (Fundulus heteroclitus) is a model environmental organism that has an extremely low assimilation rate of environmental arsenic. As a first step in elucidating the mechanism behind this phenomenon, we used quantitative real-time PCR to identify aquaglyceroporins (AQPs), which are arsenite transporters, in the killifish gill. A novel homolog killifish AQP3 (kfAQP3a) was cloned from the killifish gill, and a second homolog was identified as the consensus from a transcriptome database (kfAQP3b). The two were 99% homologous to each other, 98% homologous to a previously identified killifish AQP3 from embryos (kfAQP3ts), and 78% homologous to hAQP3. Expression of kfAQP3a in Xenopus oocytes significantly enhanced water, glycerol, and urea transport. However, kfAQP3a expressed in HEK293T cells did not transport significant amounts of arsenic. All sequence motifs thought to confer the ability of AQP3 to transport solutes were conserved in kfAQP3a, kfAQP3b, and kfAQP3ts; however, the C-terminal amino acids were different in kfAQP3a versus the other two homologs. Replacement of the three C-terminal amino acids of kfAQP3 (GKS) with the three C-terminal amino acids of kfAQP3b and kfAQP3ts (ANC) was sufficient to enable kfAQP3a to robustly transport arsenic. Thus, the C-terminus of kfAQP3b and kfAQP3ts confers arsenic selectivity in kfAQP3. Moreover, kfAQP3a, the only AQP expressed in killifish gill, is the first aquaglyceroporin identified that does not transport arsenic, which may explain, in part, why killifish poorly assimilate arsenic and are highly tolerant to environmental arsenic.

  9. The killifish, fundulus heteroclitus, second intermediate host of the trematode, Ascocotyle (Phagicola) dimunuta

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    1955-01-01

    Ascocotyle (Phagicola) diminuta was described by Stunkard and Haviland (1924)from the intestine of wild rats collected at the Clason Point dump near New York by the City Board of Health. Feeding experiments have demonstrated that metacercariae encysted in the gills of the common killifish, Fundulus hetero clitus, are stages in the life-cycle of this parasite. The larvae have been found also, although rarely and in small numbers, in the gills of the striped killifish, Fundulus majalis. Since both species of Fundulus are susceptible, it appears probable that the habits of F. heteroclitus occasion greater exposure of this species to the cercariae. It is possible that infection of the fishes occurs during the spawning season when they are in water of low salinity. The asexual stages of these trematodes and the mollusks which harbor them are yet unknown.

  10. Parasite manipulation of brain monoamines in California killifish (Fundulus parvipinnis) by the trematode Euhaplorchis californiensis

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    Shaw, J.C.; Korzan, W.J.; Carpenter, R.E.; Kuris, A.M.; Lafferty, K.D.; Summers, C.H.; Overli, O.

    2009-01-01

    California killifish (Fundulus parvipinnis) infected with the brain-encysting trematode Euhaplorchis californiensis display conspicuous swimming behaviours rendering them more susceptible to predation by avian final hosts. Heavily infected killifish grow and reproduce normally, despite having thousands of cysts inside their braincases. This suggests that E. californiensis affects only specific locomotory behaviours. We hypothesised that changes in the serotonin and dopamine metabolism, essential for controlling locomotion and arousal may underlie this behaviour modification. We employed micropunch dissection and HPLC to analyse monoamine and monoamine metabolite concentrations in the brain regions of uninfected and experimentally infected fish. The parasites exerted density-dependent changes in monoaminergic activity distinct from those exhibited by fish subjected to stress. Specifically, E. californiensis inhibited a normally occurring, stress-induced elevation of serotonergic metabolism in the raphae nuclei. This effect was particularly evident in the experimentally infected fish, whose low-density infections were concentrated on the brainstem. Furthermore, high E. californiensis density was associated with increased dopaminergic activity in the hypothalamus and decreased serotonergic activity in the hippocampus. In conclusion, the altered monoaminergic metabolism may explain behavioural differences leading to increased predation of the infected killifish by their final host predators. ?? 2008 The Royal Society.

  11. Mitochondrial physiology and reactive oxygen species production are altered by hypoxia acclimation in killifish (Fundulus heteroclitus).

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    Du, Sherry N N; Mahalingam, Sajeni; Borowiec, Brittney G; Scott, Graham R

    2016-04-15

    Many fish encounter hypoxia in their native environment, but the role of mitochondrial physiology in hypoxia acclimation and hypoxia tolerance is poorly understood. We investigated the effects of hypoxia acclimation on mitochondrial respiration, O2kinetics, emission of reactive oxygen species (ROS), and antioxidant capacity in the estuarine killifish ( ITALIC! Fundulus heteroclitus). Killifish were acclimated to normoxia, constant hypoxia (5 kPa O2) or intermittent diel cycles of nocturnal hypoxia (12 h:12 h normoxia:hypoxia) for 28-33 days and mitochondria were isolated from liver. Neither pattern of hypoxia acclimation affected the respiratory capacities for oxidative phosphorylation or electron transport, leak respiration, coupling control or phosphorylation efficiency. Hypoxia acclimation also had no effect on mitochondrial O2kinetics, but ITALIC! P50(the O2tension at which hypoxia inhibits respiration by 50%) was lower in the leak state than during maximal respiration, and killifish mitochondria endured anoxia-reoxygenation without any impact on mitochondrial respiration. However, both patterns of hypoxia acclimation reduced the rate of ROS emission from mitochondria when compared at a common O2tension. Hypoxia acclimation also increased the levels of protein carbonyls and the activities of superoxide dismutase and catalase in liver tissue (the latter only occurred in constant hypoxia). Our results suggest that hypoxia acclimation is associated with changes in mitochondrial physiology that decrease ROS production and may help improve hypoxia tolerance. PMID:26896545

  12. Can Diversifying Selection Be Distinguished from History in Geographic Clines? A Population Genomic Study of Killifish (Fundulus heteroclitus)

    OpenAIRE

    Strand, Allan E.; Larissa M Williams; Marjorie F Oleksiak; Sotka, Erik E.

    2012-01-01

    A common geographical pattern of genetic variation is the one-dimensional cline. Clines may be maintained by diversifying selection across a geographical gradient but can also reflect historical processes such as allopatry followed by secondary contact. To identify loci that may be undergoing diversifying selection, we examined the distribution of geographical variation patterns across the range of the killifish (Fundulus heteroclitus) in 310 loci, including microsatellites, allozymes, and si...

  13. A novel variant of aquaporin 3 is expressed in killifish (Fundulus heteroclitus) intestine.

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    Jung, Dawoon; Adamo, Meredith A; Lehman, Rebecca M; Barnaby, Roxanna; Jackson, Craig E; Jackson, Brian P; Shaw, Joseph R; Stanton, Bruce A

    2015-05-01

    Killifish (Fundulus heteroclitus) are euryhaline teleosts that are widely used in environmental and toxicological studies, and they are tolerant to arsenic, in part due to very low assimilation of arsenic from the environment. The mechanism of arsenic uptake by the intestine, a major route of arsenic uptake in humans is unknown. Thus, the goal of this study was to determine if aquaglyceroporins (AQPs), which transport water and other small molecules including arsenite across cell membranes, are expressed in the killifish intestine, and whether AQP expression is affected by osmotic stress. Through RT-PCR and sequence analysis of PCR amplicons, we demonstrated that the intestine expresses kfAQP3a and kfAQP3b, two previously identified variants, and also identified a novel variant of killifish AQP3 (kfAQP3c) in the intestine. The variants likely represent alternate splice forms. A BLAST search of the F. heteroclitus reference genome revealed that the AQP3 gene resides on a single locus, while an alignment of the AQP3 sequence among 384 individuals from eight population ranging from Rhode Island to North Carolina revealed that its coding sequence was remarkably conserved with no fixed polymorphism residing in the region that distinguishes these variants. We further demonstrate that the novel variant transports arsenite into HEK293T cells. Whereas kfAQP3a, which does not transport arsenite, was expressed in both freshwater (FW) and saltwater (SW) acclimated fish, kfAQP3b, an arsenic transporter, was expressed only in FW acclimated fish, and kfAQP3c was expressed only in SW acclimated fish. Thus, we have identified a novel, putative splice variant of kfAQP3, kfAQP3c, which transports arsenic and is expressed only in SW acclimated fish.

  14. Cross-resistance in Gulf killifish (Fundulus grandis) populations resistant to dioxin-like compounds.

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    Oziolor, Elias M; Dubansky, Benjamin; Burggren, Warren W; Matson, Cole W

    2016-06-01

    The Houston Ship Channel (HSC) in Houston, Texas is an aquatic environment with a long history of contamination, including polychlorinated dibenzodioxins (PCDD), polychlorinated dibenzofurans (PCDF), polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and heavy metals. Populations of Gulf killifish (Fundulus grandis) from the HSC have adapted to resist developmental cardiac deformities caused by dioxin-like compounds (DLCs). Contaminants in the HSC have acted as a strong selective pressure on resident Gulf killifish populations. Rapid adaptation can lead to fitness costs, some as a direct result of the mechanisms involved in the adaptive process, whereas other adaptations may be more general. To explore potential fitness costs, we evaluated two Gulf killifish populations with documented resistance to DLC-induced cardiac teratogenesis (Patrick Bayou and Vince Bayou), and one previously characterized reference population (Gangs Bayou). We also characterized a previously unstudied population from Galveston Bay as an additional reference population (Smith Point). We tested the sensitivity of F1 larvae from these four populations to two classes of pesticides (pyrethroid (permethrin) and carbamate (carbaryl)) and two model pro-oxidants (tert-butyl hydroquinone (tBHQ) and tert-butyl hydroperoxide (tBOOH)). In addition, we explored their responses to hypoxia and measured resting metabolic rates (M.O2). Both adapted populations were cross-resistant to the toxicity of carbaryl and both pro-oxidants tested. There were no population differences in sensitivity to permethrin. On the other hand, one reference population (Gangs Bayou) was less sensitive to hypoxia, and maintained a lower M.O2 . However, there were no differences in hypoxia tolerance or resting metabolic rate between the second reference and the two adapted populations. This investigation emphasizes the importance of including multiple reference populations to clearly link fitness costs or

  15. Developmental exposure to a complex PAH mixture causes persistent behavioral effects in naive Fundulus heteroclitus (killifish) but not in a population of PAH-adapted killifish.

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    Brown, D R; Bailey, J M; Oliveri, A N; Levin, E D; Di Giulio, R T

    2016-01-01

    Acute exposures to some individual polycyclic aromatic hydrocarbons (PAHs) and complex PAH mixtures are known to cause cardiac malformations and edema in the developing fish embryo. However, the heart is not the only organ impacted by developmental PAH exposure. The developing brain is also affected, resulting in lasting behavioral dysfunction. While acute exposures to some PAHs are teratogenically lethal in fish, little is known about the later life consequences of early life, lower dose subteratogenic PAH exposures. We sought to determine and characterize the long-term behavioral consequences of subteratogenic developmental PAH mixture exposure in both naive killifish and PAH-adapted killifish using sediment pore water derived from the Atlantic Wood Industries Superfund Site. Killifish offspring were embryonically treated with two low-level PAH mixture dilutions of Elizabeth River sediment extract (ERSE) (TPAH 5.04 μg/L and 50.4 μg/L) at 24h post fertilization. Following exposure, killifish were raised to larval, juvenile, and adult life stages and subjected to a series of behavioral tests including: a locomotor activity test (4 days post-hatch), a sensorimotor response tap/habituation test (3 months post hatch), and a novel tank diving and exploration test (3months post hatch). Killifish were also monitored for survival at 1, 2, and 5 months over 5-month rearing period. Developmental PAH exposure caused short-term as well as persistent behavioral impairments in naive killifish. In contrast, the PAH-adapted killifish did not show behavioral alterations following PAH exposure. PAH mixture exposure caused increased mortality in reference killifish over time; yet, the PAH-adapted killifish, while demonstrating long-term rearing mortality, had no significant changes in mortality associated with ERSE exposure. This study demonstrated that early embryonic exposure to PAH-contaminated sediment pore water caused long-term locomotor and behavioral alterations in

  16. Gill Morphology and Oxygen Diffusion Distance in Juvenile Striped Killifish, Fundulus majalis

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    McEnroe, M.; Rivera, L.; La Fortune, B.; Miller, A.

    2010-12-01

    Striped killifish (Fundulus majalis) are an important estuarine forage fish. Larvae and juveniles utilize shallow marsh pools which become warm (>30 C) and hypoxic (DO environment we studied gill morphology. Gill surface area (GSA) and oxygen diffusion distance are important parameters for oxygen uptake, as expressed by Fick's Equation for diffusion. To measure these parameters fish (N=20, 20-50 mm TL) were collected from marsh pools and adjacent Long Island Sound in late summer, weighed, and measured. The gills were fixed in Karnovsky’s solution. For scanning electron microscopy (SEM) they were rinsed, dehydrated in a graded ETOH series, and critically point dried, sputter-coated and were observed with ISR-SR-50 SEM. Gill morphology (number of filaments, filament length, lamellar density, and lamellar size) were quantified using SEM. Total gill surface area (GSA) was calculated using the method of Hughes (1984); GSA = L* n* bl where L = sum of filament lengths, n = number of lamellae/mm, and bl = bilateral lamellar surface area. To measure oxygen diffusion distance from water to blood, samples were embedded in Araldite 502/Embed 812 TM plastic medium for transmission electron microscopy (TEM). Stained (uranyl acetate and calcinated lead citrate) thin sections were examined using a FEI/Philips Morgagni 268 transmission electron microscope (TEM). Gill lamellar diffusion distance was measured using the technique of Matey et al., 2008 and found to be low (1.0 µm ± 0.4; mean ± SD; N= 17). Gill structure and oxygen diffusion distance will be compared to other fishes from normoxic and hypoxic environments.

  17. Multitissue molecular, genomic, and developmental effects of the Deepwater Horizon oil spill on resident Gulf killifish (Fundulus grandis).

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    Dubansky, Benjamin; Whitehead, Andrew; Miller, Jeffrey T; Rice, Charles D; Galvez, Fernando

    2013-05-21

    The Deepwater Horizon oil rig disaster resulted in crude oil contamination along the Gulf coast in sensitive estuaries. Toxicity from exposure to crude oil can affect populations of fish that live or breed in oiled habitats as seen following the Exxon Valdez oil spill. In an ongoing study of the effects of Deepwater Horizon crude oil on fish, Gulf killifish ( Fundulus grandis ) were collected from an oiled site (Grande Terre, LA) and two reference locations (coastal MS and AL) and monitored for measures of exposure to crude oil. Killifish collected from Grande Terre had divergent gene expression in the liver and gill tissue coincident with the arrival of contaminating oil and up-regulation of cytochrome P4501A (CYP1A) protein in gill, liver, intestine, and head kidney for over one year following peak landfall of oil (August 2011) compared to fish collected from reference sites. Furthermore, laboratory exposures of Gulf killifish embryos to field-collected sediments from Grande Terre and Barataria Bay, LA, also resulted in increased CYP1A and developmental abnormalities when exposed to sediments collected from oiled sites compared to exposure to sediments collected from a reference site. These data are predictive of population-level impacts in fish exposed to sediments from oiled locations along the Gulf of Mexico coast.

  18. Can diversifying selection be distinguished from history in geographic clines? A population genomic study of killifish (Fundulus heteroclitus.

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    Allan E Strand

    Full Text Available A common geographical pattern of genetic variation is the one-dimensional cline. Clines may be maintained by diversifying selection across a geographical gradient but can also reflect historical processes such as allopatry followed by secondary contact. To identify loci that may be undergoing diversifying selection, we examined the distribution of geographical variation patterns across the range of the killifish (Fundulus heteroclitus in 310 loci, including microsatellites, allozymes, and single nucleotide polymorphisms. We employed two approaches to detect loci under strong diversifying selection. First, we developed an automated method to identify clinal variation on a per-locus basis and examined the distribution of clines to detect those that exhibited signifcantly steeper slopes. Second, we employed a classic [Formula: see text]-outlier method as a complementary approach. We also assessed performance of these techniques using simulations. Overall, latitudinal clines were detected in nearly half of all loci genotyped (i.e., all eight microsatellite loci, 12 of 16 allozyme loci and 44% of the 285 SNPs. With the exception of few outlier loci (notably mtDNA and malate dehydrogenase, the positions and slopes of Fundulus clines were statistically indistinguishable. The high frequency of latitudinal clines across the genome indicates that secondary contact plays a central role in the historical demography of this species. Our simulation results indicate that accurately detecting diversifying selection using genome scans is extremely difficult in species with a strong signal of secondary contact; neutral evolution under this history produces clines as steep as those expected under selection. Based on these results, we propose that demographic history can explain all clinal patterns observed in F. heteroclitus without invoking natural selection to either establish or maintain the pattern we observe today.

  19. Application of endocrine disruptor screening program fish short-term reproduction assay: Reproduction and endocrine function in fathead minnow (Pimephales promelas) and killifish (Fundulus heteroclitus) exposed to Bermuda pond sediment.

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    Fort, Douglas J; Mathis, Michael; Fort, Chelsea E; Fort, Hayley M; Bacon, Jamie P

    2015-06-01

    A modified tier 1 Endocrine Disruptor Screening Program (EDSP) 21-d fish short-term reproduction assay (FSTRA) was used to evaluate the effects of sediment exposure from freshwater and brackish ponds in Bermuda on reproductive fecundity and endocrine function in fathead minnow (Pimephales promelas) and killifish (Fundulus heteroclitus). Reproductively active male and female fish were exposed to control sediment and sediment from 2 freshwater ponds (fathead minnow) and 2 marine ponds (killifish) contaminated with polyaromatic hydrocarbons and metals via flow-through exposure for 21 d. Reproductive fecundity was monitored daily. At termination, the status of the reproductive endocrine system was assessed by the gonadosomatic index, gonadal histology, plasma steroids (estrogen [E2], testosterone [T], and 11-ketotestosterone [11-KT]), steroidogenic enzymes (aromatase and combined 3β/17β -hydroxysteroid dehydrogenase [3β/17β-HSD]), and plasma vitellogenin (VTG). Decreased reproductive fecundity, lower male body weight, and altered endocrinological measures of reproductive status were observed in both species. Higher plasma T levels in female minnows and 11-KT levels in both male and female minnows and female killifish exposed to freshwater and brackish sediments, respectively. Decreased female E2 and VTG levels and gonadal cytochrome P19 (aromatase) activity were also found in sediment exposed females from both species. No effect on female 3β/17β-HSD activity was found in either species. The FSTRA provided a robust model capable of modification to evaluate reproductive effects of sediment exposure in fish. PMID:25565366

  20. The chlorinated AHR ligand 3,3′,4,4′,5-pentachlorobiphenyl (PCB126) promotes reactive oxygen species (ROS) production during embryonic development in the killifish (Fundulus heteroclitus)

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    Arzuaga, Xabier; Wassenberg, Deena; Giulio, Richard D.; Elskus, Adria

    2006-01-01

    Exposure to dioxin-like chemicals that activate the aryl hydrocarbon receptor (AHR) can result in increased cellular and tissue production of reactive oxygen species (ROS). Little is known of these effects during early fish development. We used the fish model, Fundulus heteroclitus, to determine if the AHR ligand and pro-oxidant 3,3′,4,4′,5-pentachlorobiphenyl (PCB126) can increase ROS production during killifish development, and to test a novel method for measuring ROS non-invasively in a living organism. The superoxide-sensitive fluorescent dye, dihydroethidium (DHE), was used to detect in ovo ROS production microscopically in developing killifish exposed to PCB126 or vehicle. Both in ovo CYP1A activity (ethoxyresorufin-o-deethylase, EROD) and in ovo ROS were induced by PCB126. In ovo CYP1A activity was inducible by PCB126 concentrations as low as 0.003 nM, with maximal induction occurring at 0.3 nM PCB126. These PCB126 concentrations also significantly increased in ovo ROS production in embryonic liver, ROS being detectable as early as 5 days post-fertilization. These data demonstrate that the pro-oxidant and CYP1A inducer, PCB126, increases both CYP1A activity and ROS production in developing killifish embryos. The superoxide detection assay (SoDA) described in this paper provides a semi-quantitative, easily measured, early indicator of altered ROS production that can be used in conjunction with simultaneous in ovo measurements of CYP1A activity and embryo development to explore functional relationships among biochemical, physiological and developmental responses to AHR ligands.

  1. Regulation of pregnane-X-receptor, CYP3A and P-glycoprotein genes in the PCB-resistant killifish (Fundulus heteroclitus) population from New Bedford Harbor

    Energy Technology Data Exchange (ETDEWEB)

    Gräns, Johanna; Wassmur, Britt; Fernández-Santoscoy, María [Department of Biological and Environmental Sciences, University of Gothenburg, Box 463, SE 405 30 Gothenburg (Sweden); Zanette, Juliano; Woodin, Bruce R.; Karchner, Sibel I. [Biology Department, MS #32, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States); Nacci, Diane E.; Champlin, Denise; Jayaraman, Saro [Office of Research and Development, National Health and Environmental Effects Research Laboratory, Atlantic Ecology Division, United States Environmental Protection Agency, 27 Tarzwell Drive, Narragansett, RI 02882 (United States); Hahn, Mark E.; Stegeman, John J. [Biology Department, MS #32, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States); Celander, Malin C., E-mail: malin.celander@gu.se [Department of Biological and Environmental Sciences, University of Gothenburg, Box 463, SE 405 30 Gothenburg (Sweden)

    2015-02-15

    Highlights: • Basal levels of PXR and Pgp mRNA are lower in liver of fish from NBH than from SC. • Hepatic PXR, CYP3A and Pgp mRNA levels are induced by PCB in fish from NBH. • Both non-dioxin-like and dioxin-like PCBs induce PXR, CYP3A and Pgp in NBH fish. • Branchial PXR and CYP3A mRNA levels are induced by PCB 126 in fish from SC. • There is possible cross-talk between AhR and PXR signaling in killifish. - Abstract: Killifish survive and reproduce in the New Bedford Harbor (NBH) in Massachusetts (MA), USA, a site severely contaminated with polychlorinated biphenyls (PCBs) for decades. Levels of 22 different PCB congeners were analyzed in liver from killifish collected in 2008. Concentrations of dioxin-like PCBs in liver of NBH killifish were ∼400 times higher, and the levels of non-dioxin-like PCBs ∼3000 times higher than in killifish from a reference site, Scorton Creek (SC), MA. The NBH killifish are known to be resistant to the toxicity of dioxin-like compounds and to have a reduced aryl hydrocarbon receptor (AhR) signaling response. Little is known about the responses of these fish to non-dioxin-like PCBs, which are at extraordinarily high levels in NBH fish. In mammals, some non-dioxin-like PCB congeners act through nuclear receptor 1I2, the pregnane-X-receptor (PXR). To explore this pathway in killifish, a PXR cDNA was sequenced and its molecular phylogenetic relationship to other vertebrate PXRs was determined. Killifish were also collected in 2009 from NBH and SC, and after four months in the laboratory they were injected with a single dose of either the dioxin-like PCB 126 (an AhR agonist) or the non-dioxin-like PCB 153 (a mammalian PXR agonist). Gills and liver were sampled three days after injection and transcript levels of genes encoding PXR, cytochrome P450 3A (CYP3A), P-glycoprotein (Pgp), AhR2 and cytochrome P450 1A (CYP1A) were measured by quantitative PCR. As expected, there was little effect of PCB exposure on mRNA expression of

  2. Clonal hybrids of the common laboratory fish Fundulus heteroclitus.

    OpenAIRE

    Dawley, R M

    1992-01-01

    All-female hybrids of the killifishes Fundulus heteroclitus and Fundulus diaphanus, known from two sites in Nova Scotia, Canada, are shown to reproduce clonally. Isozyme analysis of crosses between female hybrids and male F. heteroclitus reveals that their progeny are genetically identical and show no evidence of recombination or paternal inheritance. Flow cytometric measurement of DNA content shows the hybrids to be diploid, with DNA values intermediate to those of the parental species. Beca...

  3. Toxicity of Orimulsion-400 to early life stages of Atlantic herring (Clupea harengus) and mummichog (Fundulus heteroclitus).

    Science.gov (United States)

    Boudreau, Monica; Sweezey, Michael J; Lee, Kenneth; Hodson, Peter V; Courtenay, Simon C

    2009-06-01

    The toxicity of Orimulsion-400 (PDVSA-BITOR), an emulsion of 70% bitumen in 30% water, was tested during the embryonic development of Atlantic herring (Clupea harengus) and mummichog (Fundulus heteroclitus) in duplicate experiments. Air injection and different salinities were included in the herring assays to examine their effects on Orimulsion-400 toxicity. Water-accommodated fractions (WAFs) of no. 6 fuel oil were tested in the mummichog assays to compare Orimulsion-400 toxicity with that of a heavy fuel oil. Concentrations of Orimulsion-400 as low as 0.001% (v/v) were harmful to both species. In herring, the more sensitive of the two species, this concentration produced 100% abnormal larvae. Similar abnormalities, including pericardial edema and spinal deformities, the same signs of toxicity caused by heavy fuel oils and polycyclic aromatic hydrocarbons (PAHs), were produced in both herring and mummichog. Fish exposed to Orimulsion-400 also suffered from increased mortality, reduced heart rates, premature hatch, and reduced lengths compared to control fish. Orimulsion-400 was approximately 300-fold more toxic than the WAFs of no. 6 fuel oil. Salinity had few clear effects on Orimulsion-400 toxicity, but aeration of test solutions greatly reduced toxicity by causing bitumen to coalesce and float. Aeration also removed toxic chemicals such as PAHs. The present study suggests that in the event of a spill, Orimulsion-400 could impair fish recruitment, but that strong wave action would reduce toxicity by accelerating the removal of emulsified bitumen from the water column. PMID:19220074

  4. Inferring Evolution of Habitat Usage and Body Size in Endangered, Seasonal Cynopoeciline Killifishes from the South American Atlantic Forest through an Integrative Approach (Cyprinodontiformes: Rivulidae.

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    Wilson J E M Costa

    Full Text Available Cynopoecilines comprise a diversified clade of small killifishes occurring in the Atlantic Forest, one of the most endangered biodiversity hotspots in the world. They are found in temporary pools of savannah-like and dense forest habitats, and most of them are highly threatened with extinction if not already extinct. The greatest gap in our knowledge of cynopoecilines stems from the absence of an integrative approach incorporating molecular phylogenetic data of species still found in their habitats with phylogenetic data taken from the rare and possibly extinct species without accessible molecular information. An integrative analysis combining 115 morphological characters with a multigene dataset of 2,108 bp comprising three nuclear loci (GLYT1, ENC1, Rho, provided a robust phylogeny of cynopoeciline killifishes, which was herein used to attain an accurate phylogenetic placement of nearly extinct species. The analysis indicates that the most recent common ancestor of the Cynopoecilini lived in open vegetation habitats of the Atlantic Forest of eastern Brazil and was a miniature species, reaching between 25 and 28 mm of standard length. The rare cases of cynopoecilines specialized in inhabiting pools within dense forests are interpreted as derived from four independent evolutionary events. Shifts in habitat usage and biogeographic patterns are tentatively associated to Cenozoic paleogeographic events, but the evolutionary history of cynopoecilines may be partially lost by a combination of poor past sampling and recent habitat decline. A sharp evolutionary shift directed to increased body size in a clade encompassing the genera Campellolebias and Cynopoecilus may be related to a parallel acquisition of an internally-fertilizing reproductive strategy, unique among aplocheiloid killifishes. This study reinforces the importance of adding morphological information to molecular databases as a tool to understand the biological complexity of organisms

  5. Functional Genomics of Physiological Plasticity and Local Adaptation in Killifish

    OpenAIRE

    Whitehead, Andrew; Galvez, Fernando; Zhang, Shujun; Larissa M Williams; Oleksiak, Marjorie F

    2010-01-01

    Evolutionary solutions to the physiological challenges of life in highly variable habitats can span the continuum from evolution of a cosmopolitan plastic phenotype to the evolution of locally adapted phenotypes. Killifish (Fundulus sp.) have evolved both highly plastic and locally adapted phenotypes within different selective contexts, providing a comparative system in which to explore the genomic underpinnings of physiological plasticity and adaptive variation. Importantly, extensive variat...

  6. Habitat Function of a Restored Salt Marsh: Post-Larval Gulf Killifish as a Sentinel

    Science.gov (United States)

    Successful marsh restoration requires recreating conditions to ensure proper ecosystem function. One approach to monitor restoration success is using a sentinel species as a proxy integrator of salt marsh function. The gulf killifish (Fundulus grandis, Baird and Girard) is a goo...

  7. HISTOPATHOLOGICAL EVIDENCE OF REGENERATION FOLLOWING HEPATOTOXIC EFFECTS OF THE CYANOTOXIN MICROCYSTIN-LR IN THE HARDHEAD CATFISH AND GULF KILLIFISH.

    Science.gov (United States)

    The cyanobacterial toxin, microcystin-LR (MC-LR), causes liver damage in several freshwater fish species. The damage appears to be acute and irreversible. In the present study, two estuarine species, hardhead catfish, Arius felis, and gulf killifish, Fundulus grandis, were inject...

  8. Genetic architecture of evolved tolerance to PCBs in the estuarine fish Fundulus heteroclitus

    Science.gov (United States)

    Populations of Atlantic killifish (F. heteroclitus) resident to coastal estuarine habitats contaminated with halogenated aromatic hydrocarbons (HAHs) exhibit heritable resistance to the early life-stage toxicity associated with these compounds. Beyond our knowledge of the aryl hy...

  9. Chronic exposure of killifish to a highly polluted environment desensitizes estrogen-responsive reproductive and biomarker genes

    Energy Technology Data Exchange (ETDEWEB)

    Bugel, Sean M., E-mail: Sean.Bugel@oregonstate.edu [Department of Environmental and Molecular Toxicology, Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97331 (United States); Bonventre, Josephine A. [Department of Environmental and Molecular Toxicology, Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97331 (United States); White, Lori A. [Department of Biochemistry and Microbiology, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901 (United States); Tanguay, Robert L. [Department of Environmental and Molecular Toxicology, Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97331 (United States); Cooper, Keith R. [Department of Biochemistry and Microbiology, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901 (United States)

    2014-07-01

    Highlights: • Reproductive biomarker genes in Newark Bay killifish are desensitized to estrogen. • Gene desensitization indicates pre-transcriptional effects on estrogen signaling. • Desensitization does not have a metabolic or epigenetic basis (gene methylation). • Modulation of vitellogenin and choriogenin genes correlates with reproductive impacts. • Choriogenin L appears less prone to false negatives and may be a sensitive biomarker. - Abstract: Reproductive and endocrine disruption is commonly reported in aquatic species exposed to complex contaminant mixtures. We previously reported that Atlantic killifish (Fundulus heteroclitus) from the chronically contaminated Newark Bay, NJ, exhibit multiple endocrine disrupting effects, including inhibition of vitellogenesis (yolk protein synthesis) in females and false negative vitellogenin biomarker responses in males. Here, we characterized the effects on estrogen signaling and the transcriptional regulation of estrogen-responsive genes in this model population. First, a dose–response study tested the hypothesis that reproductive biomarkers (vtg1, vtg2, chg H, chg Hm, chg L) in Newark Bay killifish are relatively less sensitive to 17β-estradiol at the transcriptional level, relative to a reference (Tuckerton, NJ) population. The second study assessed expression for various metabolism (cyp1a, cyp3a30, mdr) and estrogen receptor (ER α, ER βa, ER βb) genes under basal and estrogen treatment conditions in both populations. Hepatic metabolism of 17β-estradiol was also evaluated in vitro as an integrated endpoint for adverse effects on metabolism. In the third study, gene methylation was evaluated for promoters of vtg1 (8 CpGs) and vtg2 (10 CpGs) in both populations, and vtg1 promoter sequences were examined for single nucleotide polymorphism (SNPs). Overall, these studies show that multi-chemical exposures at Newark Bay have desensitized all reproductive biomarkers tested to estrogen. For example, at 10 ng

  10. Dietary fat assimilation and bile salt absorption in the killifish intestine

    International Nuclear Information System (INIS)

    Radiolabeled taurocholate (TC) and triolein were used to study fat assimilation and bile salt absorption in the stomachless saltwater killifish, Fundulus heteroclitus. Fat absorption occurred primarily in the proximal intestine with approximately 87% of a single dose (9 mg fat/8 g fish) absorbed in 2 h. Luminal triolein hydrolysis and enterocyte triolein resynthesis were tightly coupled. Killifish gallbladder bile contains taurocholate and cholate in an equal molar ratio at a combined concentration of 237 +/- 25 mM (n = 10) in 24-h-fasted fish. During fat assimilation luminal bile salt and fatty acid concentrations ranged between 10 and 30 mM. Between and during meals the total concentration of bile salts in the intestinal tissue remained roughly constant (4-6 mM) with the proximal one-third of the intestine containing 40% of the total and the remainder equally distributed between the mid and distal regions. All three regions of the intestine rapidly incorporated ingested TC in vivo, with the amount incorporated proportional to the pool size. In contrast, in vitro at low TC concentrations (60 nM), the distal one-third of the intestine incorporated 10 times as much TC in 2-min uptake experiments as the proximal and mid regions. Although there are many similarities between fat and bile salt assimilation in killifish and mammals, overall the processes are much simpler in killifish

  11. Coordinated Speed Oscillations in Schooling Killifish Enrich Social Communication

    Science.gov (United States)

    Swain, Daniel T.; Couzin, Iain D.; Leonard, Naomi Ehrich

    2015-10-01

    We examine the spatial dynamics of individuals in small schools of banded killifish ( Fundulus diaphanus) that exhibit rhythmic, oscillating speed, typically with sustained, coordinated, out-of-phase speed oscillations as they move around a shallow water tank. We show that the relative motion among the fish yields a periodically time-varying network of social interactions that enriches visually driven social communication. The oscillations lead to the regular making and breaking of occlusions, which we term "switching." We show that the rate of convergence to consensus (biologically, the capacity for individuals in groups to achieve effective coordinated motion) governed by the switching outperforms static alternatives, and performs as well as the less practical case of every fish sensing every other fish. We show further that the oscillations in speed yield oscillations in relative bearing between fish over a range that includes the angles previously predicted to be optimal for a fish to detect changes in heading and speed of its neighbors. To investigate systematically, we derive and analyze a dynamic model of interacting agents that move with oscillatory speed. We show that coordinated circular motion of the school leads to systematic cycling of spatial ordering of agents and possibilities for enriched spatial density of measurements of the external environment. Our results highlight the potential benefits of dynamic communication topologies in collective animal behavior, and suggest new, useful control laws for the distributed coordination of mobile robotic networks.

  12. A rapid transcriptome response is associated with desiccation resistance in aerially-exposed killifish embryos.

    Directory of Open Access Journals (Sweden)

    Angèle Tingaud-Sequeira

    Full Text Available Delayed hatching is a form of dormancy evolved in some amphibian and fish embryos to cope with environmental conditions transiently hostile to the survival of hatchlings or larvae. While diapause and cryptobiosis have been extensively studied in several animals, very little is known concerning the molecular mechanisms involved in the sensing and response of fish embryos to environmental cues. Embryos of the euryhaline killifish Fundulus heteroclitus advance dvelopment when exposed to air but hatching is suspended until flooding with seawater. Here, we investigated how transcriptome regulation underpins this adaptive response by examining changes in gene expression profiles of aerially incubated killifish embryos at ∼100% relative humidity, compared to embryos continuously flooded in water. The results confirm that mid-gastrula embryos are able to stimulate development in response to aerial incubation, which is accompanied by the differential expression of at least 806 distinct genes during a 24 h period. Most of these genes (∼70% appear to be differentially expressed within 3 h of aerial exposure, suggesting a broad and rapid transcriptomic response. This response seems to include an early sensing phase, which overlaps with a tissue remodeling and activation of embryonic development phase involving many regulatory and metabolic pathways. Interestingly, we found fast (0.5-1 h transcriptional differences in representatives of classical "stress" proteins, such as some molecular chaperones, members of signalling pathways typically involved in the transduction of sensor signals to stress response genes, and oxidative stress-related proteins, similar to that described in other animals undergoing dormancy, diapause or desiccation. To our knowledge, these data represent the first transcriptional profiling of molecular processes associated with desiccation resistance during delayed hatching in non-mammalian vertebrates. The exceptional transcriptomic

  13. Mitochondrial Fitness, Gene Expression, and Hypoxic Stress in a Hybrid Population of the Killifish, Fundulus Heteroclitus

    Science.gov (United States)

    The physiological link between oxygen availability and mitochondrial function is well established. However, whether or not fitness variation is associated with mitochondrial genotypes in the field remains a contested topic in evolutionary biology. In this study we draw on a popul...

  14. Heritable oxidative phosphorylation differences in a pollutant resistant Fundulus heteroclitus population.

    Science.gov (United States)

    Du, Xiao; Crawford, Douglas L; Nacci, Diane E; Oleksiak, Marjorie F

    2016-08-01

    Populations can adapt to stress including recent anthropogenic pollution. Our published data suggests heritable differences in hepatocyte oxidative phosphorylation (OxPhos) metabolism in field-caught killifish (Fundulus heteroclitus) from the highly polluted Elizabeth River, VA, USA, relative to fish from a nearby, relatively unpolluted reference site in King's Creek VA. Consistent with other studies showing that Elizabeth River killifish are resistant to some of the toxic effects of certain contaminants, OxPhos measurements in hepatocytes from field-caught King's Creek but not field-caught Elizabeth River killifish were altered by acute benzo [a] pyrene exposures. To more definitively test whether the enhanced OxPhos metabolism and toxicity resistance are heritable, we measured OxPhos metabolism in a laboratory-reared F3 generation from the Elizabeth River population versus a laboratory-reared F1 generation from the King's Creek population and compared these results to previous data from the field-caught fish. The F3 Elizabeth River fish compared to F1 King's Creek fish had significantly higher State 3 respiration (routine metabolism) and complex II activity, and significantly lower complex I activity. The consistently higher routine metabolism in the F3 and field-caught Elizabeth River fish versus F1 and field-caught King's Creek fish implies a heritable change in OxPhos function. The observation that LEAK, E-State, Complex I and Complex II were different in laboratory bred versus field-caught fish suggests that different physiological mechanisms produce the enhanced OxPhos differences. Finally, similar to field-caught Elizabeth River fish, acute benzo [a] pyrene exposure did not affect OxPhos function of the laboratory-reared F3 generation, supporting the heritability of the toxicity resistance. Overall, these results suggest that the Elizabeth River population has evolved genetic changes in physiological homeostasis that enhance routine metabolism, and we

  15. Genomic and genotoxic responses to controlled weathered-oil exposures confirm and extend field studies on impacts of the Deepwater Horizon oil spill on native killifish.

    Directory of Open Access Journals (Sweden)

    Whitney Pilcher

    Full Text Available To understand the ecotoxicological impacts of the Deepwater Horizon oil spill, field studies provide a context for ecological realism but laboratory-based studies offer power for connecting biological effects with specific causes. As a complement to field studies, we characterized genome-wide gene expression responses of Gulf killifish (Fundulus grandis to oil-contaminated waters in controlled laboratory exposures. Transcriptional responses to the highest concentrations of oiled water in the laboratory were predictive of field-observed responses that coincided with the timing and location of major oiling. The transcriptional response to the low concentration (∼ 10-fold lower than the high concentration was distinct from the high concentration and was not predictive of major oiling in the field. The high concentration response was characterized by activation of the molecular signaling pathway that facilitates oil metabolism and oil toxicity. The high concentration also induced DNA damage. The low concentration invoked expression of genes that may support a compensatory response, including genes associated with regulation of transcription, cell cycle progression, RNA processing, DNA damage, and apoptosis. We conclude that the gene expression response detected in the field was a robust indicator of exposure to the toxic components of contaminating oil, that animals in the field were exposed to relatively high concentrations that are especially damaging to early life stages, and that such exposures can damage DNA.

  16. Annual Killifish Transcriptomics and Candidate Genes for Metazoan Diapause.

    Science.gov (United States)

    Thompson, Andrew W; Ortí, Guillermo

    2016-09-01

    Dormancy has evolved in all major metazoan lineages. It is critical for survival when environmental stresses are not conducive to growth, maturation, or reproduction. Embryonic diapause is a form of dormancy where development is reversibly delayed and metabolism is depressed. We report the diapause transcriptome of the annual killifish Nematolebias whitei, and compare gene expression between diapause embryos and free-living larvae to identify a candidate set of 945 differentially expressed "diapause" genes for this species. Similarity of transcriptional patterns among N. whitei and other diapausing animals is striking for a small set of genes associated with stress resistance, circadian rhythm, and metabolism, while other genes show discordant patterns. Although convergent evolution of diapause may require shared molecular mechanisms for fundamental processes, similar physiological phenotypes also may arise through modification of alternative pathways. Annual killifishes are a tractable model system for comparative transcriptomic studies on the evolution of diapause. PMID:27297470

  17. Genetic diversity and population history of the endangered killifish Aphanius baeticus.

    Science.gov (United States)

    Gonzalez, Elena G; Pedraza-Lara, Carlos; Doadrio, Ignacio

    2014-01-01

    The secondary freshwater fish fauna of the western-Iberian Peninsula basin is primarily restricted to local coastal streams, and man-made salt evaporation ponds, etc., which are susceptible to periodical flood and drought events. Despite its uniqueness in ecological adaptation to high saltwater tolerance, very little is known about this fauna's population dynamics and evolutionary history. The killifish, Aphanius baeticus (Cyprinodontidae) is an endemic species restricted to river basins on Spain's southern Atlantic coastline, considered as "Endangered." In this study, the genetic structure, diversity and historical demography of A. baeticus were analyzed using mitochondrial (cytochrome b, N=131) and nuclear (4 out of 19 microsatellites tested, N=288) markers across its distribution range. The phylogenetic and networking reconstruction revealed subtle phylogeographic structuring. A scattered expansion at the beginning of the interglacial periods, coupled with posterior events of extinction and colonization caused by periodical cycles of flooding, could explain the absence of well-defined phylogenetic relationships among populations. Moreover, very low genetic diversity values and a weak population differentiation were detected. We proposed that dispersals allowed by periodic floods connecting river drainages may have promoted a wide genetic exchange among populations and could have contributed to the current genetic relatedness of these populations.

  18. ULTRASTRUCTURE OF NORMAL AND NEOPLASTIC EXOCRINE PANCREAS IN THE MUMMICHOG, FUNDULUS HETEROLCLITUS

    Science.gov (United States)

    The ultrastructure of normal exocrine pancreas and exocrine pancreatic neoplasms in Fundulus heteroclitus from a creosote-contaminated environment in the Elizabeth River, Virginia, is described. he normal exocrine pancreas in this species was an anastomosing tubular rather than a...

  19. Diet of four annual killifishes: an intra and interspecific comparison

    Directory of Open Access Journals (Sweden)

    Gabriel Laufer

    2009-03-01

    Full Text Available We examined the diet of 4 annual fishes, Austrolebias viarius, Austrolebias cheradophilus, Austrolebias luteoflammulatus and Cynopoecilus melanotaenia inhabiting temporal ponds of southeastern Uruguay, by analysis of stomach contents. Fishes were captured from fifty ephemeral ponds of Castillos Lagoon basin, in the region of the Humedales del Este. We identified 13099 individual prey items extracted from 669 stomachs of the four captured species. In the studied system, annual killifishes represents the most abundant and conspicuous top predators. Killifishes are generalist key predators at the ephemeral ponds of the studied system, consuming mostly aquatic items. Zooplancton represented the bulk of the diet in the four analyzed species, followed by eggs, algae and diatoms. Insects are the next group in prey number, as follows: Diptera larvae (especially Chironomidae and Cullicidae, Ephemeroptera (especially Betidae, and coleopteran larvae (especially Dytiscidae. Acari are also important prey in number. The four fish species differ in diet composition and in diet richness. A general pattern of differences in diet richness among killifish species and demographic groups could be related to variations in body sizes. As top predators annual killifishes are an important component of the temporal pond ecosystems. Understanding the natural history of this species and their communities is necessary in order to conserve them.Nós examinamos a dieta de 4 peixes anuais, Austrolebias viarius, Austrolebias cheradophilus, Austrolebias luteoflammulatus e Cynopoecilus melanotaenia, que habitam poças temporárias do sudeste do Uruguai, através da análise de conteúdo estomacal. Os peixes foram capturados em cinco poças temporárias da bacia da lagoa Castillos, na região de Humedales del Este. Nós identificamos 13099 itens de presas estraídos de 669 estômagos das quatro espécies. No sistema estudado, peixes anuais representam os predadores de topo mais

  20. Molecular cloning and brain distribution of three types of gonadotropin-releasing hormone from mummichog Fundulus heteroclitus.

    Science.gov (United States)

    Ohkubo, M; Aranishi, F; Shimizu, A

    2010-02-01

    Complementary DNAs encoding gonadotropin-releasing hormone (GnRH) precursors were cloned from the mummichog Fundulus heteroclitus brain, showing that this species has three GnRH forms, i.e. medaka Oryzias latipes GnRH (mdGnRH), chicken GnRH-II (cGnRH-II) and Atlantic salmon Salmo salar GnRH (sGnRH). The F. heteroclitus prepro GnRHs have common structural architectures of vertebrate GnRHs, consisting of the signal peptide, 10 amino acids of mature peptide, GKR sequence and GnRH-associated peptide (GAP). Phylogenetic analysis of fish prepro GnRHs showed that F. heteroclitus mdGnRH is a homologue of sbGnRHs and mdGnRHs of other acanthopterygian. Quantitative real-time PCR revealed that mdGnRH was abundantly expressed in the olfactory bulb and in olfactory lobe areas and is expressed in the pituitary. The cGnRH-II was mainly expressed in the midbrain and interbrain areas, and the sGnRH was expressed not only in the olfactory bulb but also in other regions of the brain. These results suggest that the mdGnRH is involved in the stimulation of gonadotrophs in the pituitary, whereas cGnRH-II and sGnRH are involved in neurotransmission and neuromodulation. PMID:20738714

  1. CHRONIC LABORATORY EXPOSURE OF MUMMICHOG, FUNDULUS HETEROCLITUS, TO PAH-CONTAMINATED SEDIMENT AND DIET CAUSES LIVER NEOPLASMS

    Science.gov (United States)

    The mummichog, Fundulus heteroclitus, is a common estuarine teleost inhabiting tidal marshes of the eastern United States. We previoiusly reported on high prevalences of hepatic and extra-hepatic neoplasms in populations of this species from chemically contaminated environments ...

  2. POPULATION GENETIC STRUCTURE OF A NON-MIGRATORY MARINE FISH FUNDULUS HETERCLITUS ACROSS A STRONG GRADIENT OF PCB CONTAMINATION

    Science.gov (United States)

    Populations of the estuarine fish Fundulus heteroclitus indigenous to contaminated sites exhibit heritable resistance to some of the toxic effects of early life-stage exposure to polychlorinated biphenyls (PCBs). This evolved tolerance provides evidence of strong selection by PCB...

  3. Infestation and Pathological Alterations by Ergasilus sarsi (Copepoda) on the Tanganyika Killifish from Africa

    OpenAIRE

    Kilian, Esmari; Avenant-Oldewage, Annemariè

    2013-01-01

    A total of 204 Ergasilus sarsi, a copepod, were collected from Tanganyika Killifish Lamprichthys tanganicanus in Lake Tanganyika during March 2010. The prevalence was 86.40%, the mean intensity was 7.56, and the mean abundance was 6.38. Only 27 of the fish were infested, and the highest infestation on one fish was 29. Proliferation of mucus cells and lamellar fusion occurred. Haemorrhage due to blood vessel compression was noted. This is the first record of E. sarsi from Tanganyika Killifish....

  4. FunnyBase: a systems level functional annotation of Fundulus ESTs for the analysis of gene expression

    Directory of Open Access Journals (Sweden)

    Kolell Kevin J

    2004-12-01

    Full Text Available Abstract Background While studies of non-model organisms are critical for many research areas, such as evolution, development, and environmental biology, they present particular challenges for both experimental and computational genomic level research. Resources such as mass-produced microarrays and the computational tools linking these data to functional annotation at the system and pathway level are rarely available for non-model species. This type of "systems-level" analysis is critical to the understanding of patterns of gene expression that underlie biological processes. Results We describe a bioinformatics pipeline known as FunnyBase that has been used to store, annotate, and analyze 40,363 expressed sequence tags (ESTs from the heart and liver of the fish, Fundulus heteroclitus. Primary annotations based on sequence similarity are linked to networks of systematic annotation in Gene Ontology (GO and the Kyoto Encyclopedia of Genes and Genomes (KEGG and can be queried and computationally utilized in downstream analyses. Steps are taken to ensure that the annotation is self-consistent and that the structure of GO is used to identify higher level functions that may not be annotated directly. An integrated framework for cDNA library production, sequencing, quality control, expression data generation, and systems-level analysis is presented and utilized. In a case study, a set of genes, that had statistically significant regression between gene expression levels and environmental temperature along the Atlantic Coast, shows a statistically significant (P Conclusion The methods described have application for functional genomics studies, particularly among non-model organisms. The web interface for FunnyBase can be accessed at http://genomics.rsmas.miami.edu/funnybase/super_craw4/. Data and source code are available by request at jpaschall@bioinfobase.umkc.edu.

  5. Genetic Diversity and Population History of the Endangered Killifish Aphanius baeticus

    OpenAIRE

    González, Elena G.; Pedraza-Lara, Carlos; Doadrio, Ignacio

    2014-01-01

    The secondary fresh-water fish fauna of the western-Iberian Peninsula basin is primary restricted to local coastal streams, salt water creeks, and man-made salt evaporation ponds, which are susceptible to periodical flood and drought events. Despite their uniqueness in ecological adaptation to high salt-water tolerance, very little is known about their population dynamics and evolutionary history. The killifish, Aphanius baeticus (Cyprinodontidae) is an endemic species restricted to river bas...

  6. Morphology-diet relationships in four killifishes (Teleostei, Cyprinodontidae, Orestias) from Lake Titicaca

    OpenAIRE

    Maldonado, E; Hubert, Nicolas; Sagnes, P.; Mérona, Bernard de

    2009-01-01

    This study explores the relationship between morphology and diet in four Andean killifishes (Orestias) from Lake Titicaca that are known to differ in habitat use. Species that fed preferentially on amphipods (Orestias albus) or molluscs (Orestias luteus) separated in multivariate space from other species that feed on cladocera and algae (Orestias agassii and Orestias jussiei). Generally, specimens feeding on cladocera were characterized by a short, blunt nose with a small mouth; whereas, spec...

  7. Burst speciation processes and genomic expansion in the neotropical annual killifish genus Austrolebias (Cyprinodontiformes, Rivulidae).

    Science.gov (United States)

    García, G; Gutiérrez, V; Ríos, N; Turner, B; Santiñaque, F; López-Carro, B; Folle, G

    2014-02-01

    The extent to which genome sizes and other nucleotypic factors influence the phyletic diversification of lineages has long been discussed but remains largely unresolved. In the present work, we present evidence that the genomes of at least 16 species of the neotropical rivulid killifish genus Austrolebias are unusually large, with an average DNA content of about 5.95 ± 0.45 picograms per diploid cell (mean C-value of about 2.98 pg). They are thus larger than the genomes of very nearly all other diploid, i.e. non-(paleo) polyploid species of actinopterygian fishes so far reported. Austrolebias species appear to be conventional diploids in all other respects and there is no reason to believe that they arise from polyploid ancestors. The genome sizes reported for other rivulid killifishes, including a putative sister group, are considerably smaller and fall within the range typical of most other cyprinodontoid species. Therefore, it appears that the ancestor(s) of contemporary Austrolebias have undergone one or more episodes of genome expansion encompassing sudden speciation process during the Pleistocene. In addition, these findings are consistent with the hypothesis of a positive correlation between species richness and genome size.

  8. Acclimation of killifish to thermal extremes of hot spring: Transcription of gonadal and liver heat shock genes.

    Science.gov (United States)

    Akbarzadeh, Arash; Leder, Erica H

    2016-01-01

    In this study, we explored the hypothesis that killifish acclimate to thermal extremes through regulation of genes involved in stress and metabolism. We examined the liver and gonadal transcription of heat shock proteins (hsp70, hsp90a, hsp90b), glucokinase (gck), and high mobility group b1 (hmgb1) protein in wild killifish species from hot springs and rivers using quantitative real-time PCR. Moreover, we exposed a river killifish species to a long-term thermal regime of hot spring (37-40°C) and examined the liver transcription of the heat shock genes. Our results showed that hot spring killifish showed a significant, strong upregulation of liver hsp90a. Moreover, the testicular transcript levels of hsp90a, hsp90b, and hsp70 were higher in hot spring killifish than the river ones. The results of the common garden experiments showed that the transcripts of hsp70, hsp90b, and hmgb1 were mildly induced (> twofold) at the time when temperature reached to 37-40°C, while the transcripts of hsp90a were strongly induced (17-fold increase). The level of hsp90a was dramatically more upregulated when fish were maintained in thermal extreme (42-fold change higher than in ambient temperature). Moreover, a significant downregulation of gck transcripts was observed at the time when temperature was raised to 37-40°C (80-fold decrease) and during exposure to long-term thermal extreme (56-fold decrease). It can be concluded that the regulation of heat shock genes particularly hsp90a might be a key factor of the acclimation of fish to high temperature environments like hot springs.

  9. The evolution of an annual life cycle in killifish: adaptation to ephemeral aquatic environments through embryonic diapause.

    Science.gov (United States)

    Furness, Andrew I

    2016-08-01

    An annual life cycle is characterized by growth, maturity, and reproduction condensed into a single, short season favourable to development, with production of embryos (seeds, cysts, or eggs) capable of surviving harsh conditions which juveniles or adults cannot tolerate. More typically associated with plants in desert environments, or temperate-zone insects exposed to freezing winters, the evolution of an annual life cycle in vertebrates is fairly novel. Killifish, small sexually dimorphic fishes in the Order Cyprinodontiformes, have adapted to seasonally ephemeral water bodies across much of Africa and South America through the independent evolution of an annual life history. These annual killifish produce hardy desiccation-resistant eggs that undergo diapause (developmental arrest) and remain buried in the soil for long periods when fish have perished due to the drying of their habitat. Killifish are found in aquatic habitats that span a continuum from permanent and stable to seasonal and variable, thus providing a useful system in which to piece together the evolutionary history of this life cycle using natural comparative variation. I first review adaptations for life in ephemeral aquatic environments in killifish, with particular emphasis on the evolution of embryonic diapause. I then bring together available evidence from a variety of approaches and provide a scenario for how this annual life cycle evolved. There are a number of features within Aplocheiloidei killifish including their inhabitation of marginal or edge aquatic habitat, their small size and rapid attainment of maturity, and egg properties that make them particularly well suited to the colonization of ephemeral waters. PMID:25969869

  10. Interindividual variation in Complex I activity in Fundulus heteroclitus along a steep thermocline.

    Science.gov (United States)

    Loftus, Samuel J; Crawford, Douglas L

    2013-01-01

    The first enzyme in the oxidative phosphorylation pathway is Complex I (EC 1.6.5.3). Complex I is a large heteromeric enzyme complex with 45 protein subunits that translocates H(+) ions across the mitochondrial inner membrane. Among northern and southern populations of the teleost fish Fundulus heteroclitus, Complex I subunits have fixed amino acid substitutions. Additionally, there are differences in oxidative phosphorylation activity among populations of F. heteroclitus. To investigate whether these differences are related to Complex I, enzyme activity was measured in 121 individuals from five populations of F. heteroclitus and its sister species Fundulus grandis acclimated to a constant 20°C temperature. Within each population, Complex I activity is highly variable among individuals of F. heteroclitus (coefficient of variation percentage among individuals has a mean of 90% in the five F. heteroclitus populations), and the mean Complex I activity among populations is significantly different at the latitudinal extremes of the range. Importantly, Complex I activity is more similar between F. heteroclitus from the southernmost population and its sister species F. grandis than to the northern populations of F. heteroclitus, suggesting important evolutionary differences. Unexpectedly, the activity is nearly fourfold higher in southern populations than northern populations. Mitochondrial density appears to compensate partially for decreased activity in northern individuals; activity per wet weight is only twofold higher in southern populations. We suggest that some of the variation in Complex I activity is genetically based and thus is being influenced by directional selection. However, this conclusion presents a conundrum: there should not be so much variation in Complex I activity within a population if this variation is biologically important.

  11. Control of Cl-transport in the operculum epithelium of Fundulus heteroclitus : long- and short-term salinity adaptation

    DEFF Research Database (Denmark)

    Hoffmann, E.K.; Hoffmann, Erik; Lang, F.;

    2002-01-01

    The eurohaline fish, Fundulus heteroclitus, adapts rapidly to enhanced salinity by increasing the ion secretion by gill chloride cells. An increase of similar to 70 mOsm in plasma osmolarity was previously found during the transition. To mimic this in vitro, isolated opercular epithelia of seawater......-adapted Fundulus mounted in a modified Ussing chamber were exposed to an increase in NaCl and/or osmolarity on the basolateral side, which immediately increased I-SC. Various Cl- channel blockers as well as the K+ channel blocker Ba2+ added to the basolateral side all inhibited the steady-state as well...... as the hypertonic stimulation of I-SC. The There Exists-agonist isoproterenol stimulates I-SC in standard Ringer solutions. In contrast, when cell volume was kept at the larger value by simultaneous addition of water, the stimulation with isoproterenol was abolished, suggesting that the key process for activation...

  12. Control of Cl- transport in the operculum epithelium of Fundulus heteroclitus: long- and short-term salinity adaptation

    DEFF Research Database (Denmark)

    Hoffmann, E K; Hoffmann, E; Lang, F;

    2002-01-01

    The eurohaline fish, Fundulus heteroclitus, adapts rapidly to enhanced salinity by increasing the ion secretion by gill chloride cells. An increase of approximately 70 mOsm in plasma osmolarity was previously found during the transition. To mimic this in vitro, isolated opercular epithelia...... of seawater-adapted Fundulus mounted in a modified Ussing chamber were exposed to an increase in NaCl and/or osmolarity on the basolateral side, which immediately increased I(SC). Various Cl(-) channel blockers as well as the K(+) channel blocker Ba(2+) added to the basolateral side all inhibited the steady......-state as well as the hypertonic stimulation of I(SC). The exists -agonist isoproterenol stimulates I(SC) in standard Ringer solutions. In contrast, when cell volume was kept at the larger value by simultaneous addition of water, the stimulation with isoproterenol was abolished, suggesting that the key process...

  13. The use of annual killifish in the biocontrol of the aquatic stages of mosquitoes in temporary bodies of fresh water; a potential new tool in vector control

    Directory of Open Access Journals (Sweden)

    Adrias Araceli Q

    2010-05-01

    Full Text Available Abstract Background Mosquitoes that breed in temporary pools in remote areas that dry up seasonally are especially difficult to control through chemical or biological means. The annual killifish has been suggested as a means of eradicating the aquatic stages of mosquitoes in transient pools because they can maintain permanent populations in such habitats by undergoing suspended animation or diapause during the embryonic stages to survive periodic drought. However, very little is known about the predatory activity of annual killifish and their usefulness in mosquito control. Results The annual killifish, Nothobranchius guentheri, native to Tanzania, was used in this investigation. Food preference was tested under laboratory conditions by feeding juvenile killifish with 2nd instar mosquito larvae of Culex quinquefasciatus in the presence of alternative food sources, such as rotifers and chironomid larvae. Semi-field tests were conducted by introduction of hibernating killifish embryos and juvenile fish to artificial ponds in an outdoor open environment that allowed natural oviposition of Cx. quinquefasciatus. Food preference studies show that N. guentheri preferred to prey on mosquito larvae than either chironomid or rotifers. When hibernating killifish embryos were added to ponds simultaneously with the addition of freshwater, the embryos hatched and fed on mosquito larval population resulting in complete elimination of the immature stages. The introduction of juvenile fish to ponds with high density of mosquito larvae resulted in total eradication of the mosquito population due to predation by fish. Complete biocontrol of the mosquito larval population was achieved in the presence of 3 fish per m2 of pond surface area. Conclusions The annual killifish provides yet another tool that may be employed in the eradication diseases carried by mosquitoes through vector control, particularly in temporary bodies of freshwater. The fish can be conveniently

  14. Reproduction of the threatened Annual Killifish Austrolebias nigrofasciatus (Cyprinodontiformes: Rivulidae, confined in a natural environment

    Directory of Open Access Journals (Sweden)

    M.V. Volcan

    2011-06-01

    Full Text Available This study concerns the reproduction of Austrolebias nigrofasciatus, an endangered annual fish species endemic to the waters of the São Gonçalo channel and its tributaries in southern Brazil. Three breeding pairs confined in small cages for four weeks in their biotope were observed to produce an average of 21.5 plus or minus 12.0 eggs/week/female, with a range of 3-39 eggs/female/week. Average egg diameter was 1.51 plus or minus 0.12 mm, with abrupt changes observed throughout the period of study. The mean oviposition observed was within the range found for other killifishes and demonstrates the high fecundity rate of the species even under confinement conditions.

  15. The complete mitochondrial genome of the killifish Orestias sp. (Cyprinodontiformes, Cyprinodontidae) from the high Andean range.

    Science.gov (United States)

    Quezada-Romegialli, Claudio; Guerrero, Claudia Jimena; Véliz, David; Vila, Irma

    2016-07-01

    The killifish genus Orestias is endemic to freshwater ecosystems in the High Andes of Peru, Bolivia and Chile. Phylogenetic and phylogeographic studies with partial mitochondrial genes have failed to resolve relationship among species, needing more comprehensive approaches. In this study, we described the complete mitochondrial genome of Orestias sp. from Lirima, northern Chile, with the aim to provide useful data for phylogenetic purposes and species delimitation. The mitochondrial genome was assembled with 2.6 million of reads obtained through an Ion Torrent (chip 318) sequencer. The circular sequence of 16,617 bp showed the following nucleotide composition: A, 26.7%, C, 27.1%, G, 17.0%, and T, 29.2%. Gene composition and structure were similar to other fish sequences available, and comprised 13 protein-coding genes, 12S and 16S rRNA, 22 tRNA genes, and a control region. PMID:26119115

  16. RNA-Seq reveals complex genetic response to deepwater horizon oil release in Fundulus grandis

    Directory of Open Access Journals (Sweden)

    Garcia Tzintzuni I

    2012-09-01

    Full Text Available Abstract Background The release of oil resulting from the blowout of the Deepwater Horizon (DH drilling platform was one of the largest in history discharging more than 189 million gallons of oil and subject to widespread application of oil dispersants. This event impacted a wide range of ecological habitats with a complex mix of pollutants whose biological impact is still not yet fully understood. To better understand the effects on a vertebrate genome, we studied gene expression in the salt marsh minnow Fundulus grandis, which is local to the northern coast of the Gulf of Mexico and is a sister species of the ecotoxicological model Fundulus heteroclitus. To assess genomic changes, we quantified mRNA expression using high throughput sequencing technologies (RNA-Seq in F. grandis populations in the marshes and estuaries impacted by DH oil release. This application of RNA-Seq to a non-model, wild, and ecologically significant organism is an important evaluation of the technology to quickly assess similar events in the future. Results Our de novo assembly of RNA-Seq data produced a large set of sequences which included many duplicates and fragments. In many cases several of these could be associated with a common reference sequence using blast to query a reference database. This reduced the set of significant genes to 1,070 down-regulated and 1,251 up-regulated genes. These genes indicate a broad and complex genomic response to DH oil exposure including the expected AHR-mediated response and CYP genes. In addition a response to hypoxic conditions and an immune response are also indicated. Several genes in the choriogenin family were down-regulated in the exposed group; a response that is consistent with AH exposure. These analyses are in agreement with oligonucleotide-based microarray analyses, and describe only a subset of significant genes with aberrant regulation in the exposed set. Conclusion RNA-Seq may be successfully applied to feral and

  17. Arabian killifish (Aphanius dispar) embryos: A model organism for the risk assessment of the Arabian Gulf coastal waters.

    Science.gov (United States)

    Saeed, Suhur; Al-Naema, Nayla; Butler, Josh D; Febbo, Eric J

    2015-12-01

    Fish embryos are excellent models for studies aimed at understanding toxic mechanisms and indications of possible acute and chronic effects. For the past 3 yr, an Arabian killifish (Aphanius dispar) fish embryo test has been developed in the authors' laboratory as a routine ecotoxicological test that can be used to support risk assessment of potential contaminants in Arabian Gulf coastal waters. Tests were conducted with 3 reference toxicants (3,4-dichloroaniline [DCA], sodium dodecyl sulfate, and zinc sulfate [Zn]) and chlorine, a disinfectant used widely in industrial cooling systems around the Arabian Gulf region. The 50% effect concentration (EC50) for DCA was 0.47 mg/L and 1.89 mg/L for embryos exposed before 6 hpf and after 168 hpf, respectively. Sublethal effects were mainly observed at concentrations above 2.5 mg/L, the effects included severe pericardial edema and tail shortage. The sodium dodecyl sulfate ionic surfactant caused mortality at both early and late stages of embryo development; it caused coagulation, severe deformity, and hemolysis. Both the EC50 and the 50% lethal concentration (LC50) for sodium dodecyl sulfate were 9.37 mg/L. Salinity influenced the toxicity of Zn to killifish embryos: at 40 psu Zn was found not to be toxic, whereas at 20 psu toxicity had increased significantly (p experiment. The LC50 for chlorine was determined to be 0.08 mg/L. Examination of the existing literature showed similar results to the present study's findings. The results suggest a more comparable sensitivity of killifish embryos to that of other fish embryo test recommended species. The present study's findings support the ability of killifish to be an indicator organism for environmental risk assessments of Arabian Gulf waters. Benefits include sensitivity to a wide range of substances and conditions, animal alternative, ease of fish breeding, and clarity of the embryos. PMID:26184573

  18. Discovery of endangered annual killifish Austrolebias cheradophilus (Aplocheiloidei: Rivulidae) in Brazil, with comments on habitat, population structure and conservation status

    OpenAIRE

    Luis Esteban Krause Lanés; Ândrio Cardozo Gonçalves; Matheus Vieira Volcan

    2014-01-01

    Austrolebias genus comprises about 40 small annual killifishes endemic to South America and their highest diversity occurs in southern Brazil and Uruguay, especially in drainages of Patos-Mirim system. Austrolebiasspecies are severely threatened with extinction because their life cycle and restricted ranges. Low dispersal ability and the extensive loss and fragmentation of freshwater wetlands contribute to this threat. Accurate information on the geographic distribution and ecology of the spe...

  19. Postzygotic Isolation Evolves before Prezygotic Isolation between Fresh and Saltwater Populations of the Rainwater Killifish, Lucania parva

    OpenAIRE

    Kozak, Genevieve M.; Arthur B. Rudolph; Colon, Beatrice L.; Fuller, Rebecca C.

    2012-01-01

    Divergent natural selection has the potential to drive the evolution of reproductive isolation. The euryhaline killifish Lucania parva has stable populations in both fresh water and salt water. Lucania parva and its sister species, the freshwater L. goodei, are isolated by both prezygotic and postzygotic barriers. To further test whether adaptation to salinity has led to the evolution of these isolating barriers, we tested for incipient reproductive isolation within L. parva by crossing fresh...

  20. Fish and robot dancing together: bluefin killifish females respond differently to the courtship of a robot with varying color morphs.

    Science.gov (United States)

    Phamduy, P; Polverino, G; Fuller, R C; Porfiri, M

    2014-09-01

    The experimental integration of bioinspired robots in groups of social animals has become a valuable tool to understand the basis of social behavior and uncover the fundamental determinants of animal communication. In this study, we measured the preference of fertile female bluefin killifish (Lucania goodei) for robotic replicas whose aspect ratio, body size, motion pattern, and color morph were inspired by adult male killifish. The motion of the fish replica was controlled via a robotic platform, which simulated the typical courtship behavior observed in killifish males. The positional preferences of females were measured for three different color morphs (red, yellow, and blue). While variation in preference was high among females, females tend to spend more time in the vicinity of the yellow painted robot replicas. This preference may have emerged because the yellow robot replicas were very bright, particularly in the longer wavelengths (550–700 nm) compared to the red and blue replicas. These findings are in agreement with previous observations in mosquitofish and zebrafish on fish preference for artificially enhanced yellow pigmentation. PMID:25162832

  1. Fish and robot dancing together: bluefin killifish females respond differently to the courtship of a robot with varying color morphs

    International Nuclear Information System (INIS)

    The experimental integration of bioinspired robots in groups of social animals has become a valuable tool to understand the basis of social behavior and uncover the fundamental determinants of animal communication. In this study, we measured the preference of fertile female bluefin killifish (Lucania goodei) for robotic replicas whose aspect ratio, body size, motion pattern, and color morph were inspired by adult male killifish. The motion of the fish replica was controlled via a robotic platform, which simulated the typical courtship behavior observed in killifish males. The positional preferences of females were measured for three different color morphs (red, yellow, and blue). While variation in preference was high among females, females tend to spend more time in the vicinity of the yellow painted robot replicas. This preference may have emerged because the yellow robot replicas were very bright, particularly in the longer wavelengths (550–700 nm) compared to the red and blue replicas. These findings are in agreement with previous observations in mosquitofish and zebrafish on fish preference for artificially enhanced yellow pigmentation. (paper)

  2. Predator-driven brain size evolution in natural populations of Trinidadian killifish (Rivulus hartii).

    Science.gov (United States)

    Walsh, Matthew R; Broyles, Whitnee; Beston, Shannon M; Munch, Stephan B

    2016-07-13

    Vertebrates exhibit extensive variation in relative brain size. It has long been assumed that this variation is the product of ecologically driven natural selection. Yet, despite more than 100 years of research, the ecological conditions that select for changes in brain size are unclear. Recent laboratory selection experiments showed that selection for larger brains is associated with increased survival in risky environments. Such results lead to the prediction that increased predation should favour increased brain size. Work on natural populations, however, foreshadows the opposite trajectory of evolution; increased predation favours increased boldness, slower learning, and may thereby select for a smaller brain. We tested the influence of predator-induced mortality on brain size evolution by quantifying brain size variation in a Trinidadian killifish, Rivulus hartii, from communities that differ in predation intensity. We observed strong genetic differences in male (but not female) brain size between fish communities; second generation laboratory-reared males from sites with predators exhibited smaller brains than Rivulus from sites in which they are the only fish present. Such trends oppose the results of recent laboratory selection experiments and are not explained by trade-offs with other components of fitness. Our results suggest that increased male brain size is favoured in less risky environments because of the fitness benefits associated with faster rates of learning and problem-solving behaviour. PMID:27412278

  3. Physiological strategies during animal diapause: lessons from brine shrimp and annual killifish.

    Science.gov (United States)

    Podrabsky, Jason E; Hand, Steven C

    2015-06-01

    Diapause is a programmed state of developmental arrest that typically occurs as part of the natural developmental progression of organisms that inhabit seasonal environments. The brine shrimp Artemia franciscana and annual killifish Austrofundulus limnaeus share strikingly similar life histories that include embryonic diapause as a means to synchronize the growth and reproduction phases of their life history to favorable environmental conditions. In both species, respiration rate is severely depressed during diapause and thus alterations in mitochondrial physiology are a key component of the suite of characters associated with cessation of development. Here, we use these two species to illustrate the basic principles of metabolic depression at the physiological and biochemical levels. It is clear that these two species use divergent molecular mechanisms to achieve the same physiological and ecological outcomes. This pattern of convergent physiological strategies supports the importance of biochemical and physiological adaptations to cope with extreme environmental stress and suggests that inferring mechanism from transcriptomics or proteomics or metabolomics alone, without rigorous follow-up at the biochemical and physiological levels, could lead to erroneous conclusions. PMID:26085666

  4. Interaction of fish aryl hydrocarbon receptor paralogs (AHR1 and AHR2) with the retinoblastoma protein

    Energy Technology Data Exchange (ETDEWEB)

    Merson, Rebeka R., E-mail: rmerson@ric.edu [Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States); Biology Department, Rhode Island College, 500 Mt. Pleasant Ave., Providence, RI 02908 (United States); Karchner, Sibel I.; Hahn, Mark E. [Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States)

    2009-08-13

    The aryl hydrocarbon receptor (AHR) mediates the toxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related compounds. In some mammalian cell lines, TCDD induces G1 cell cycle arrest, which depends on an interaction between the AHR and the retinoblastoma tumor suppressor (RB). Mammals possess one AHR, whereas fishes possess two or more AHR paralogs that differ in the domains important for AHR-RB interactions in mammals. To test the hypothesis that fish AHR paralogs differ in their ability to interact with RB, we cloned RB cDNA from Atlantic killifish, Fundulus heteroclitus, and studied the interactions of killifish RB protein with killifish AHR1 and AHR2. In coimmunoprecipitation experiments, in vitro-expressed killifish RB coprecipitated with both AHR1 and AHR2. Consistent with these results, both killifish AHR1 and AHR2 interacted with RB in mammalian two-hybrid assays. These results suggest that both fish AHR1 and AHR2 paralogs may have the potential to influence cell proliferation through interactions with RB.

  5. Interaction of fish aryl hydrocarbon receptor paralogs (AHR1 and AHR2) with the retinoblastoma protein

    International Nuclear Information System (INIS)

    The aryl hydrocarbon receptor (AHR) mediates the toxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related compounds. In some mammalian cell lines, TCDD induces G1 cell cycle arrest, which depends on an interaction between the AHR and the retinoblastoma tumor suppressor (RB). Mammals possess one AHR, whereas fishes possess two or more AHR paralogs that differ in the domains important for AHR-RB interactions in mammals. To test the hypothesis that fish AHR paralogs differ in their ability to interact with RB, we cloned RB cDNA from Atlantic killifish, Fundulus heteroclitus, and studied the interactions of killifish RB protein with killifish AHR1 and AHR2. In coimmunoprecipitation experiments, in vitro-expressed killifish RB coprecipitated with both AHR1 and AHR2. Consistent with these results, both killifish AHR1 and AHR2 interacted with RB in mammalian two-hybrid assays. These results suggest that both fish AHR1 and AHR2 paralogs may have the potential to influence cell proliferation through interactions with RB.

  6. The complete mitochondrial genome of the endemic and threatened killifish Orestias ascotanensis Parenti, 1984 (Cyprinodontiformes, Cyprinodontidae) from the High Andes.

    Science.gov (United States)

    Quezada-Romegialli, Claudio; Guerrero, Claudia Jimena; Véliz, David; Vila, Irma

    2016-07-01

    The killifish Orestias ascotanensis is endemic to the small isolated springs of Ascotán salt pan in the Central High Andes, Chile. Due to small populations, mining activity, and increasing aridity, this species is catalogued in danger of extinction. The complete mitochondrial genome of O. ascotanesis was assembled with an Ion Torrent sequencer (chip 318) that produced 2.61 million of reads. The 16 617 bp of the entire genome consisted of 22 transfer RNAs, 2 ribosomal RNAs, 13 protein-coding genes, and a control region, showing that the gene composition and arrangement match to that reported for most fishes. PMID:26152352

  7. Local adaptation to altitude underlies divergent thermal physiology in tropical killifishes of the genus Aphyosemion.

    Directory of Open Access Journals (Sweden)

    David J McKenzie

    Full Text Available In watersheds of equatorial West Africa, monophyletic groups of killifish species (genus Aphyosemion occur in discrete altitudinal ranges, low altitude species (LA, sea level to ∼350 m or high altitude species (HA, 350 to 900 m. We investigated the hypothesis that local adaptation to altitude by the LA and HA species would be revealed as divergent effects of temperature on their physiological energetics. Two species from each group (mass ∼350 mg were acclimated to 19, 25 and 28°C, with 19 and 28°C estimated to be outside the thermal envelope for LA or HA, respectively, in the wild. Wild-caught animals (F0 generation were compared with animals raised in captivity at 25°C (F1 generation to investigate the contribution of adaptation versus plasticity. Temperature significantly increased routine metabolic rate in all groups and generations. However, LA and HA species differed in the effects of temperature on their ability to process a meal. At 25°C, the specific dynamic action (SDA response was completed within 8 h in all groups, but acclimation to temperatures beyond the thermal envelope caused profound declines in SDA performance. At 19°C, the LA required ∼14 h to complete the SDA, whereas the HA required only ∼7 h. The opposite effect was observed at 28°C. This effect was evident in both F0 and F1. Reaction norms for effects of temperature on SDA therefore revealed a trade-off, with superior performance at warmer temperatures by LA being associated with inferior performance at cooler temperatures, and vice-versa in HA. The data indicate that divergent physiological responses to temperature in the LA and HA species reflect local adaptation to the thermal regime in their habitat, and that local adaptation to one thermal environment trades off against performance in another.

  8. Mitochondrial DNA Sequence and Lack of Response to Anoxia in the Annual Killifish Austrofundulus limnaeus

    Science.gov (United States)

    Wagner, Josiah T.; Herrejon Chavez, Florisela; Podrabsky, Jason E.

    2016-01-01

    The annual killifish Austrofundulus limnaeus inhabits ephemeral ponds in regions of Venezuela, South America. Permanent populations of A. limnaeus are maintained by production of stress-tolerant embryos that are able to persist in the desiccated sediment. Previous work has demonstrated that A. limnaeus have a remarkable ability to tolerate extended periods of anoxia and desiccating conditions. After considering temperature, A. limnaeus embryos have the highest known tolerance to anoxia when compared to any other vertebrate yet studied. Oxygen is completely essential for the process of oxidative phosphorylation by mitochondria, the intracellular organelle responsible for the majority of adenosine triphosphate production. Thus, understanding the unique properties of A. limnaeus mitochondria is of great interest. In this work, we describe the first complete mitochondrial genome (mtgenome) sequence of a single adult A. limnaeus individual and compare both coding and non-coding regions to several other closely related fish mtgenomes. Mitochondrial features were predicted using MitoAnnotator and polyadenylation sites were predicted using RNAseq mapping. To estimate the responsiveness of A. limnaeus mitochondria to anoxia treatment, we measure relative mitochondrial DNA copy number and total citrate synthase activity in both relatively anoxia-tolerant and anoxia-sensitive embryonic stages. Our cross-species comparative approach identifies unique features of ND1, ND5, ND6, and ATPase-6 that may facilitate the unique phenotype of A. limnaeus embryos. Additionally, we do not find evidence for mitochondrial degradation or biogenesis during anoxia/reoxygenation treatment in A. limnaeus embryos, suggesting that anoxia-tolerant mitochondria do not respond to anoxia in a manner similar to anoxia-sensitive mitochondria.

  9. Linking habitat structure to life history strategy: Insights from a Mediterranean killifish

    Science.gov (United States)

    Cavraro, Francesco; Daouti, Irini; Leonardos, Ioannis; Torricelli, Patrizia; Malavasi, Stefano

    2014-01-01

    Modern theories of life history evolution deal with finding links between environmental factors, demographic structure of animal populations and the optimal life history strategy. Small-sized teleost fish, occurring in fragmented populations under contrasting environments, have been widely used as study models to investigate these issues. In the present study, the Mediterranean killifish Aphanius fasciatus was used to investigate the relationships between some habitat features and life history strategy. We selected four sites in the Venice lagoon inhabited by this species, exhibiting different combinations of two factors: overall adult mortality, related to intertidal water coverage and a consequent higher level of predator exposure, and the level of sediment organic matter, as indicator of habitat trophic richness. Results showed that these were the two most important factors influencing demography and life history traits in the four sites. Fish from salt marshes with high predator pressure were smaller and produced a higher number of eggs, whereas bigger fish and a lower reproductive investment were found in the two closed, not tidally influenced habitats. Habitat richness was positively related with population density, but negatively related with growth rate. In particular the synergy between high resources and low predation level was found to be important in shaping peculiar life history traits. Results were discussed in the light of the interactions between selective demographic forces acting differentially on age/size classes, such as predation, and habitat trophic richness that may represent an important energetic constraint on life history traits. The importance to link habitat productivity and morphology to demographic factors for a better understanding of the evolution of life history strategy under contrasting environments was finally suggested.

  10. Closing of the Tethys Sea and the phylogeny of Eurasian killifishes (Cyprinodontiformes: Cyprinodontidae).

    Science.gov (United States)

    Hrbek, T; Meyer, A

    2003-01-01

    To test vicariant speciation hypotheses derived from geological evidence of the closing of the Tethys Sea, we reconstruct phylogenetic relationships of the predominantly fresh-water killifish genus Aphanius using 3263 aligned base pairs of mitochondrial DNA from samples representing 49 populations of 13 species. We use additional 11 cyprinodontid species as outgroup taxa. Genes analysed include those encoding the partial 12S and 16S ribosomal RNAs; transfer RNAs for valine, leucine, isoleucine, glutamine, methionine, tryptophan, alanine, asparagine, cysteine and tyrosine; and complete nicotinamide adenine dinucleotide dehydrogenase subunit I and II. Molecular substitution rate for this DNA region is estimated at of 8.6 +/- 0.1 x 10(-9) substitutions base pair(-1) year(-1), and is derived from a well dated transgression of the Red Sea into the Wadi Sirhan of Jordan 13 million years ago; an alternate substitution rate of 1.1 +/- 0.2 x 10(-8) substitutions base pair(-1) year(-1) is estimated from fossil evidence. Aphanius forms two major clades which correspond to the former eastern and western Tethys Sea. Within the eastern clade Oligocene divergence into a fresh-water clade inhabiting the Arabian Peninsula and an euhaline clade inhabiting coastal area from Pakistan to Somalia is observed. Within the western Tethys Sea clade we observe a middle Oligocene divergence into Iberian Peninsula and Atlas Mountains, and Turkey and Iran sections. Within Turkey we observe a large amount of genetic differentiation correlated with late Miocene orogenic events. Based on concordance of patterns of phylogenetic relationships and area relationships derived from geological and fossil data, as well as temporal congruence of these patterns, we support a predominantly vicariant-based speciation hypothesis for the genus Aphanius. An exception to this pattern forms the main clade of A. fasciatus, an euhaline circum-Mediterranean species, which shows little genetic differentiation or

  11. 2005 Atlantic Hurricanes Poster

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 2005 Atlantic Hurricanes poster features high quality satellite images of 15 hurricanes which formed in the Atlantic Basin (includes Gulf of Mexico and...

  12. South Atlantic Shrimp System

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The SEFSC, in cooperation with the South Atlantic states, collects South Atlantic shrimp data from dealers and fishermen. These data are collected to provide catch,...

  13. Salinity tolerance in diapausing embryos of the annual killifish Austrofundulus limnaeus is supported by exceptionally low water and ion permeability.

    Science.gov (United States)

    Machado, Ben E; Podrabsky, Jason E

    2007-10-01

    The annual killifish Austrofundulus limnaeus inhabits rainwater pools in the Maracaibo basin of Venezuela. This species persists in ephemeral habitats by producing diapausing embryos that are resistant to the stresses imposed by the drying of their aquatic habitat. Embryos of A. limnaeus are likely exposed to a highly variable osmotic environment during development, but their tolerance of osmotic stress has not been characterized. We investigated the capacity of these embryos to survive in hypersaline environments and evaluated the possible mechanisms used to support osmoregulation. Diapausing embryos of A. limnaeus defend their internal osmolality of around 290 mOsmol kg(-1) H(2)O(-1) against salt stress as high as 50 ppt salinity. We find that diapausing embryos of A. limnaeus have a permeability to water that is orders of magnitude lower than other teleost fish embryos. The activity of ion motive ATPases that may be important in the extrusion of ions via mitochondrial rich cells do not appear to be playing a large role in osmoregulation of A. limnaeus embryos. We conclude that for the duration of embryonic development the unique properties of the enveloping cell layer of A. limnaeus embryos acts as a permeability barrier to water and ions and supports osmoregulation in this species in response to a broad range of osmotic environments. PMID:17581754

  14. Next-generation sequencing detects repetitive elements expansion in giant genomes of annual killifish genus Austrolebias (Cyprinodontiformes, Rivulidae).

    Science.gov (United States)

    García, G; Ríos, N; Gutiérrez, V

    2015-06-01

    Among Neotropical fish fauna, the South American killifish genus Austrolebias (Cyprinodontiformes: Rivulidae) constitutes an excellent model to study the genomic evolutionary processes underlying speciation events. Recently, unusually large genome size has been described in 16 species of this genus, with an average DNA content of about 5.95 ± 0.45 pg per diploid cell (mean C-value of about 2.98 pg). In the present paper we explore the possible origin of this unparallel genomic increase by means of comparative analysis of the repetitive components using NGS (454-Roche) technology in the lowest and highest Rivulidae genomes. Here, we provide the first annotated Rivulidae-repeated sequences composition and their relative repetitive fraction in both genomes. Remarkably, the genomic proportion of the moderately repetitive DNA in Austrolebias charrua genome represents approximately twice (45%) of the repetitive components of the highly related rivulinae taxon Cynopoecilus melanotaenia (25%). Present work provides evidence about the impact of the repeat families that could be distinctly proliferated among sublineages within Rivulidae fish group, explaining the great genome size differences encompassing the differentiation and speciation events in this family.

  15. Effects of Anthropogenic Pollution on the Oxidative Phosphorylation Pathway of Hepatocytes from Natural Populations of Fundulus heteroclitus

    Energy Technology Data Exchange (ETDEWEB)

    Du, Xiao; Crawford, Douglas L.; Oleksiak, Marjorie F., E-mail: moleksiak@rsmas.miami.edu

    2015-08-15

    Highlights: • Fish from a highly polluted and clean reference population were compared. • Oxidative phosphorylation (e.g., State 3, enzymes, and proton LEAK) was quantified. • Polluted fish had lower LEAK, enzyme III and enzyme IV but higher enzyme I. • Exposures to PAH and PCB only affected individuals from the reference population. - Abstract: Persistent organic pollutants (POPs), including polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), potentially target mitochondria and cause toxicity. We compared the effects of POPs on mitochondrial respiration by measuring oxidative phosphorylation (OxPhos) metabolism in hepatocytes isolated from lab-depurated Fundulus heteroclitus from a Superfund site contaminated with PAHs (Elizabeth River VA, USA) relative to OxPhos metabolism in individuals from a relatively clean, reference population (King’s Creek VA, USA). In individuals from the polluted Elizabeth River population, OxPhos metabolism displayed lower LEAK and lower activities in complex III, complex IV, and E State, but higher activity in complex I compared to individuals from the reference King’s Creek population. To test the supposition that these differences were due to or related to the chronic PAH contamination history of the Elizabeth River population, we compared the OxPhos functions of undosed individuals from the polluted and reference populations to individuals from these populations dosed with a PAH {benzo [α] pyrene (BaP)} or a PCB {PCB126 (3,3′,4,4′,5-pentachlorobiphenyl)}, respectively. Exposure to PAH or PCB affected OxPhos in the reference King’s Creek population but had no detectable effects on the polluted Elizabeth River population. Thus, PAH exposure significantly increased LEAK, and exposure to PCB126 significantly decreased State 3, E state and complex I activity in the reference King’s Creek population. These data strongly implicate an evolved tolerance in the Elizabeth River fish where dosed

  16. Discovery of endangered annual killifish Austrolebias cheradophilus (Aplocheiloidei: Rivulidae in Brazil, with comments on habitat, population structure and conservation status

    Directory of Open Access Journals (Sweden)

    Luis Esteban Krause Lanés

    2014-03-01

    Full Text Available Austrolebias genus comprises about 40 small annual killifishes endemic to South America and their highest diversity occurs in southern Brazil and Uruguay, especially in drainages of Patos-Mirim system. Austrolebiasspecies are severely threatened with extinction because their life cycle and restricted ranges. Low dispersal ability and the extensive loss and fragmentation of freshwater wetlands contribute to this threat. Accurate information on the geographic distribution and ecology of the species, vital to plan conservation and management strategies, are scarce. In order to provide basic knowledge for annual fish conservation this paper reports the presence of Austrolebias cheradophilus and present data about its population structure (CPUA, size, sex ratio, length-weight relationships and condition factor and conservation status in southern Brazil. The estimated CPUA of populations was 0.86 fish/m2. Standard length (SL of males ranged between 32.14 and 49.17 mm and for females between 25.11 and 41.6 mm. There were no differences in SL between the sexes (t-test = - 1.678; P = 0.105, and Chi-squared test demonstrated marginal differences in proportions of sexes (2.25:1; χ2 = 3.846; P= 0.07. Allometric coefficient of the LWR was slightly hyperallometric (b = 3.08 and K of the specimens ranged from 1.84 to 2.42 (mean ± S.E. = 2.12 ± 0.04. Populations have low density and their biotopes are under critical threat, mainly due to suppression by agriculture, pastures for livestock and increase housing. The species is considered "Critically Endangered" in Brazil, furthermore is strongly recommended its inclusion on lists of endangered fauna and ensures the protection of their remaining habitats.

  17. North Atlantic Temperature Anomaly

    OpenAIRE

    Vukcevic, M.A.

    2009-01-01

    The author postulates the existence of a high correlation between North Atlantic Temperature Anomaly and the variations of magnetic field over the Hudson Bay region. Post-glacial uplift and convection in the underlying mantle uplift (as reflected in changes of the area's magnetic intensity) are making significant contribution to the Atlantic basin climate change.

  18. SUBGLACIAL VOLCANO IN ATLANTIC

    OpenAIRE

    Nakamura, Shigehisa

    2010-01-01

    This is a note to satellite monitoring of the subglacial volcano in the Atlantic. The satellite data are obtained by EUMETSAT and NASA An eruption of a subglacial volcano in Iceland had issued volcanic ash, and the winds transferred the ash to the European Union in April 2010. This volcano is one of the volcanoes in the Atlantic. There are volcanoes in the north and south Atlantic. Some of them are in Azores Islands, in Canary Islands and Cape Verde Islands. Iceland is located on the zone of ...

  19. Atlantic Salmon Telemetry Monitoring

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Annual telemetry data are collected as part of specific projects (assessments within watersheds) or as opportunistic efforts to characterize Atlantic salmon smolt...

  20. Woman Swims Atlantic

    Institute of Scientific and Technical Information of China (English)

    贾庆文

    2009-01-01

    Jennifer Figge pressed her toes into the Caribbean sand, excited and exhausted as she touched land this week for the first time in almost a month. Reaching a beach in Trinidad, she became the first woman on record to s,Mm across the Atlantic Ocean-a dream she'd had since the early 1960s, when a stormy trans-Atlantic flight got her thinking she could wear a life vest and swim the rest of the way if needed.

  1. Morphological and molecular taxonomy of a new species of Fundulotrema and comments on Gyrodactylus stephanus (Monogenea: Gyrodactylidae) from Fundulus heteroclitus (Actinopterygii: Cyprinodontiformes) in Nova Scotia, Canada.

    Science.gov (United States)

    King, Stanley D; Cone, David K

    2009-08-01

    Fundulotrema porterensis n. sp. (Monogenea: Gyrodactylidae) is described from the mummichog, Fundulus heteroclitus (L.; Cyprinodontidae), inhabiting Porters Lake, Nova Scotia, Canada. The new parasite species is characterized by having a ventral bar with small anterolateral processes and linguiform membrane, differentiating it from all other known species of Fundulotrema. The morphological description of F. porterensis is supplemented with 1011 sequenced base pairs (bp) of ribosomal DNA (rDNA) spanning both internal transcribed spacers (ITS-1 and ITS-2) and 5.8S regions of the genome. A BLAST (basic local alignment search tool) search revealed that the 5.8S (157 bp) region varied by 1 bp from Gyrodactylus turnbulli Harris, 1986 and G. pictae Cable, Oosterhout, Barson and Harris, 2005, which also infect cyprinodontids. Morphometrically, F. porterensis most closely resembles Fundulotremafoxi (Rawson, 1973), but the 2 species are easily separated by length of hamuli (50.7 vs. 42.2 microm, respectively), length of anterolateral process of the ventral bar (4.9 vs. 8.9 microm), shape of marginal hooks, and shape of the ventral bar membrane. A morphological and molecular supplemental diagnosis of Gyrodactylus stephanus Mueller, 1937, from the mummichog, is also presented. This new material provides previously unrecorded information on the attributes of the ventral bar, marginal hooks, and also clarifies the structure of the male copulatory organ (MCO). PMID:20049991

  2. North Atlantic Circulation

    Science.gov (United States)

    Molinari, R.; Bryan, K.; Schott, F.

    The intensity of the North Atlantic winddriven and thermohaline circulation and the close proximity of many oceanographic installations make the North Atlantic a particularly favored region of the world ocean from the standpoint of research in ocean circulation. Recent increases in available data and advances in numerical modeling techniques served as the impetus to convene a joint workshop of modelers and observers working on the North Atlantic with the Scientific Committee on Oceanic Research (SCOR) Working Group (WG) 68 (“North Atlantic Circulation”). Goals of the workshop were to provide an update on data sets and models and to discuss the poleward heat flux problem and possible monitoring strategies. The joint Workshop/SCOR WG-68 meeting was convened by F. Schott (chairman of the working group; Rosenstiel School of Marine and Atmospheric Science, Miami, Fla.), K. Bryan (National Oceanic and Atmospheric Administration/ Geophysical Fluid Dynamics Laboratory (NOAA/GFDL)), and R. Molinari (NOAA/Atlantic Oceanographic and Meteorological Laboratory (NOAA/AOML)).

  3. Atlantic menhaden adult tagging study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Atlantic menhaden are a schooling forage fish species, which are subject to a large commercial purse seine fishery. Atlantic menhaden are harvested for reduction...

  4. Atlantic City memories.

    Science.gov (United States)

    Epstein, Franklin H

    2008-04-01

    Fifty years ago, the Atlantic City meetings, held the first week in May of every year, were attended by all the elite of American academic medicine and all who wanted to join that group. Part of the magic of those meetings was that professors and neophytes took each other seriously and talked to each other. PMID:18382726

  5. 75 FR 44938 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; Atlantic Coastal Shark Fishery

    Science.gov (United States)

    2010-07-30

    ... National Oceanic and Atmospheric Administration RIN 0648-XX28 Atlantic Coastal Fisheries Cooperative Management Act Provisions; Atlantic Coastal Shark Fishery AGENCY: National Marine Fisheries Service (NMFS... Atlantic Coastal Fisheries Cooperative Management Act (Atlantic Coastal Act), based on the...

  6. Effects of 17α-ethinylestradiol (EE2) on reproductive endocrine status in mummichog (Fundulus heteroclitus) under differing salinity and temperature conditions.

    Science.gov (United States)

    Gillio Meina, Esteban; Lister, Andrea; Bosker, Thijs; Servos, Mark; Munkittrick, Kelly; MacLatchy, Deborah

    2013-06-15

    Exposure to 17α-ethinylestradiol (EE₂), a synthetic estrogen, has previously been shown to decrease reproductive endocrine status and egg production in northern mummichog (Fundulus heteroclitus macrolepidotus). The objective of this study was to evaluate if variations in salinity or temperature conditions of EE₂-exposed mummichog modify the effect on whole organism reproductive endocrine status and gonadal steroidogenesis. Mummichog were exposed in vivo for 14 days to 0, 50 and 250 ng/L EE₂ in 0, 16 and 32 ppt salinity at 18 °C and to 0 and 250 ng/L EE₂ at 10, 18 and 26 °C at 16 ppt. There was a little overall effect of salinity on measured endpoints. In the salinity exposure, 250 ng/L EE₂-exposed females had significantly reduced 17β-estradiol (E₂) levels. Increased temperature triggered gonadal growth in both sexes and increased plasma E₂ and E₂ production and decreased 11-KT (11-ketotestosterone) production. EE₂ counteracted the effect of temperature by depressing gonadal growth in males. In both exposures, EE₂ effects on testosterone (T) production were variable. The use of steroidogenic precursors (25-OH-cholesterol, and/or pregnenolone and/or testosterone) in the in vitro gonadal incubations indicated decreased E₂ production in females and 11-KT production in males were predominately due to suppression of the terminal conversion step between T and E₂ or 11-KT. Ovarian aromatase A (cyp19a) gene expression at 16 ppt and 18 °C was not affected by 250 ng/L EE₂ (the only treatment combinations tested). Overall, temperature is a factor regulating northern mummichog reproduction; EE₂ overrides its effects and disrupts the terminal step of steroidogenesis. Our results should be considered in designing future estuarine fish bioassays and in understanding effects of estrogenic endocrine disruptors in estuaries. PMID:23608699

  7. Two Distinct Roles of Atlantic SSTs in ENSO Variability: North Tropical Atlantic SST and Atlantic Nino

    Science.gov (United States)

    Ham, Yoo-Geun; Kug, Jong-Seong; Park, Jong-Yeon

    2013-01-01

    Two distinct roles of the Atlantic sea surface temperatures (SSTs), namely, the North Tropical Atlantic (NTA) SST and the Atlantic Nino, on the El Nino-Southern Oscillation (ENSO) variability are investigated using the observational data from 1980 to 2010 and coupled model experiments. It appears that the NTA SST and the Atlantic Nino can be used as two independent predictors for predicting the development of ENSO events in the following season. Furthermore, they are likely to be linked to different types of El Nino events. Specifically, the NTA SST cooling during February, March, and April contributes to the central Pacific warming at the subsequent winter season, while the negative Atlantic Nino event during June, July, and August contributes to enhancing the eastern Pacific warming. The coupled model experiments support these results. With the aid of a lagged inverse relationship, the statistical forecast using two Atlantic indices can successfully predict various ENSO indices.

  8. Oxidative stress responses of gulf killifish exposed to hydrocarbons from the Deepwater Horizon oil spill: Potential implications for aquatic food resources.

    Science.gov (United States)

    Crowe, Kristi M; Newton, Joseph C; Kaltenboeck, Bernhard; Johnson, Calvin

    2014-02-01

    Ecosystem effects of polycyclic aromatic hydrocarbons (PAHs) remain under investigation following the Gulf of Mexico Deepwater Horizon oil spill. Fundulus grandis, an established indicator of aquatic ecosystem health, was investigated because this species shares genes and biochemical pathways with higher trophic-level fish and plays an important role in the gulf food chain. Oxidative stress responses including hepatic cytochrome P4501A (CYP1A) and serum antioxidant capacity were evaluated in fish exposed to PAHs. Fish were exposed to water-accommodated fractions (WAFs) of crude oil (7.0  ± 0.10 mg/L C6-C28) after which solutions were diluted below the level of detection over 8 h using 15 ppt aerated artificial seawater. Before euthanasia, fish remained in aquaria for 12 h, 24 h, or 48 h. Three replicate experiments were conducted at each time point using unexposed fish as experimental controls. Significant differences (p < 0.05) in CYP1A induction were observed in exposed versus control fish at 24 h. Expression of CYP1A increased by 25%, 66%, and 23% in exposed fish at 12 h, 24 h, and 48 h, respectively. Significant increases were observed in antioxidant capacity of nonenzymatic antioxidants in exposed versus control fish at each time point. Given the activity of CYP1A, radicals formed during PAH detoxification likely resulted in increased oxidant load requiring elevated antioxidant defenses. Research is needed to determine the duration of oxidative stress responses considering the potential for lipid oxidation in exposed fish or species feeding on exposed fish.

  9. A low level of dietary selenium has both beneficial and toxic effects and is protective against Cd-toxicity in the least killifish Heterandria formosa.

    Science.gov (United States)

    Xie, Lingtian; Wu, Xing; Chen, Hongxing; Dong, Wu; Cazan, Alfy Morales; Klerks, Paul L

    2016-10-01

    As an essential element, selenium (Se) is beneficial at low levels yet toxic at high levels. The present study assessed the effects of dietary exposure to Se in the least killifish Heterandria formosa, and investigated how this exposure influences the effects of a subsequent exposure to cadmium (Cd). The fish were pre-exposed to an environmentally relevant concentration (2 μg g(-1) dry wt) of dietary selenite (Se(4+)) or seleno-l-methionine (Se-Met) for 10 d. The same fish were then exposed to 0.5 mg L(-1) of Cd for 5 d. Both Se(IV) and Se-Met rapidly accumulated in H. formosa. Results for the two Se species were generally similar in this study. Fish exposed to Se had lower levels of lipid peroxidation (measured as levels of thiobarbituric acid reactive substances or TBARS) and a higher catalase (CAT) activity. In contrast, their Na(+)/K(+)-ATPase activity was reduced. The Cd exposure resulted in an increase in lipid peroxidation and decreases in the activities of catalase and Na(+)/K(+)-ATPase. The Cd-exposed H. formosa that were pre-exposed to Se had lower Cd body burdens, less lipid peroxidation, and higher catalase activity, than did fish not pre-exposed to Se. The Se exposure did not have a protective effect on the Cd-induced reduction in Na(+)/K(+)-ATPase activity. These results clearly demonstrate that a Se-enriched diet reduces some (but not all) forms of Cd-toxicity and that Se can simultaneously have beneficial and detrimental effects, making it difficult to predict the net outcome of changes in dietary Se levels for fish.

  10. Role of inhibin and activin in the modulation of gonadotropin- and steroid-induced oocyte maturation in the teleost Fundulus heteroclitus

    Directory of Open Access Journals (Sweden)

    Toussaint Gesulla

    2007-06-01

    Full Text Available Abstract Background Activin and inhibin are glycoproteins structurally related to the transforming growth factor-beta superfamily. These peptides were first described as factors that regulate the follicle-stimulating hormone (FSH at the pituitary level. The possible role of inhibin and activin, at the ovarian level, in mediating the stimulatory actions of a Fundulus pituitary extract (FPE and 17alpha,20beta-dihydroprogesterone (DHP on oocyte maturation was investigated in this study. Methods In vitro culture of ovarian follicles and induction of oocyte maturation were carried out in 75% Leibovitz L-15 medium. Follicles or denuded oocytes were exposed to FPE, inhibin, activin, ethanol vehicle (control group, or DHP. The competence of the follicles or denuded oocytes to respond to the hormones was assessed by scoring germinal vesicle breakdown (GVBD used as an indication of the reinitiation of meiosis or oocyte maturation. DHP level was measured by radioimmunoassay. Results Addition of FPE promoted the synthesis of DHP by the granulose cells of fully grown ovarian follicles and thus stimulated GVBD in the oocyte. Presence of porcine inhibin did not hinder the synthesis of DHP stimulated by FPE, although it did inhibit the subsequent GVBD in a dose-dependent manner, suggesting that the action of inhibin was at the oocyte level. Similarly to the findings with FPE, inhibin also blocked the DHP-induced GVBD in intact follicles, as well as the spontaneous and steroid-induced GVBD of denuded oocyte. Inhibin straightforwardly blocked the response to a low dose of DHP throughout the culture period, while higher doses of the steroid appeared to overcome the inhibitory effect especially at later times. In contrast to inhibin, recombinant human activin A significantly enhanced DHP-induced GVBD in a dose-dependent manner after 48 hr, although activin alone was not able to induce GVBD without the presence of the steroid. Conclusion Taking together with our

  11. Feeding ecology of Rivulus luelingi (Aplocheiloidei: Rivulidae in a Coastal Atlantic Rainforest stream, southern Brazil

    Directory of Open Access Journals (Sweden)

    Vinícius Abilhoa

    2010-01-01

    Full Text Available Feeding habits of the killifish Rivulus luelingi collected in a black water stream of the Coastal Atlantic Rainforest in southern Brazil were investigated. Eight samplings were made between April 2003 and January 2004. The diet, assessed through a similarity matrix with the estimated contribution values of food items, included microcrustaceans, aquatic immature insects (larvae and pupae, aquatic adult insects, terrestrial insects, insect fragments, spiders, and plant fragments. Differences in the diet according to temporal variations (months were registered, but changes related with size classes evaluated and high/low precipitation period were not observed. The species presented an insectivorous feeding habit, and its diet in the studied stream was composed of autochthonous (mainly aquatic immature insects and allochthonous (mainly insect fragments material.Neste estudo foram investigados os hábitos alimentares do peixe anual Rivulus luelingi em um riacho de água escura da Floresta Atlântica Costeira do Sul do Brasil. Oito amostragens foram realizadas entre abril de 2003 e janeiro de 2004. A dieta, avaliada através de uma matriz de similaridade com os valores de contribuição estimados para os itens alimentares, inclui microcrustáceos, insetos imaturos aquáticos, insetos aquáticos e terrestres, fragmentos de insetos, aranhas e fragmentos de plantas. Diferenças relacionadas ao período amostral (meses foram registradas, mas mudanças na dieta em função das classes de tamanho avaliadas e o período de alta/baixa precipitação não foram observadas. A espécie apresentou hábito alimentar insetívoro, e sua dieta no riacho estudado foi composta por itens autóctones (principalmente insetos imaturos aquáticos e alóctones (principalmente fragmentos de insetos.

  12. 75 FR 22103 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; Atlantic Coastal Shark Fishery

    Science.gov (United States)

    2010-04-27

    ... National Oceanic and Atmospheric Administration RIN 0648-XV13 Atlantic Coastal Fisheries Cooperative Management Act Provisions; Atlantic Coastal Shark Fishery AGENCY: National Marine Fisheries Service (NMFS...-compliance; Declaration of a moratorium. SUMMARY: In accordance with the Atlantic Coastal...

  13. Atlantic Offshore Seabird Dataset Catalog

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Several bureaus within the Department of Interior compiled available information from seabird observation datasets from the Atlantic Outer Continental Shelf into a...

  14. Atlantic Flyway Sea Duck Survey

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Atlantic Flyway Sea Duck Survey, conducted from 1991 to 2002 by the U.S. Fish and Wildlife Service, was established to record sea duck numbers using near shore...

  15. Virginia Atlantic Coast Recreational Use

    Data.gov (United States)

    Virginia Department of Environmental Quality — As a member of the Mid-Atlantic Regional Council on the Ocean (MARCO), Virginia, through its Coastal Zone Management (CZM) Program, collected information on how the...

  16. VA Atlantic Coast Recreational Use

    Data.gov (United States)

    Virginia Department of Environmental Quality — As a member of the Mid-Atlantic Regional Council on the Ocean (MARCO), Virginia, through its Coastal Zone Management (CZM) Program, collected information on how the...

  17. Atlantic Flyway Breeding Waterfowl Survey

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Atlantic Flyway Technical Section initiated this breeding waterfowl survey in 11 northeast states ranging from New Hampshire to Virginia.

  18. 78 FR 59878 - Atlantic Highly Migratory Species; Commercial Atlantic Aggregated Large Coastal Shark (LCS...

    Science.gov (United States)

    2013-09-30

    ... management groups is closed, even across fishing years. On July 3, 2013 (78 FR 40318), NMFS announced the... Species; Commercial Atlantic Aggregated Large Coastal Shark (LCS), Atlantic Hammerhead Shark, Atlantic Blacknose Shark, and Atlantic Non-Blacknose Small Coastal Shark (SCS) Management Groups AGENCY:...

  19. Atlantic menhaden processing plant test tagging data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Atlantic menhaden are a schooling forage fish species, which are subject to a large commercial purse seine fishery. Atlantic menhaden are harvested for reduction...

  20. Atlantic NAD 83 OCS Planning Areas

    Data.gov (United States)

    Bureau of Ocean Energy Management, Department of the Interior — This data set contains BOEM Planning Area outlines in ESRI shapefile format for the BOEM Atlantic Region. The old Atlantic Planning Area outlines were changed as of...

  1. The North Atlantic Oscillation in the Atlantic-European SLP*

    OpenAIRE

    GLOWIENKA-HENSE, RITA

    2011-01-01

    An analysis of the signature of the North Atlantic Oscillation (NAO) in the Atlantic-European sea level pressure (SLP) is presented for observed (German Weather Service) and ECMWF T21 model data. The former time series consists of 1881–1984 January to December fields and the latter of 42 monthly fields from 3 permanent January simulations. The NAO is shown to be one of the dominant eigenmodes of SLP for all calendar months. A very similar NAO anomaly pattern is filtered from the T21 model dat...

  2. Atlantic Seaduck Project

    Science.gov (United States)

    Perry, M.C.; Hanson, Alan; Kerekes, Joseph; Paquet, Julie

    2006-01-01

    Atlantic Seaduck Project is being conducted to learn more about the breeding and moulting areas of seaducks in northern Canada and more about their feeding ecology on wintering areas, especially Chesapeake Bay. Satellite telemetry is being used to track surf scoters wintering in Chesapeake Bay, Maryland and black scoters on migrational staging areas in New Brunswick, Canada to breeding and moulting areas in northern Canada. Various techniques used to capture the scoters included mist netting, night-lighting, and net capture guns. All captured ducks were transported to a veterinary hospital where surgery was conducted following general anaesthesia procedures. A PTT100 transmitter (39 g) manufactured by Microwave, Inc., Columbia, Maryland was implanted into the duck?s abdominal cavity with an external (percutaneous) antenna. Eight of the surf scoters from Chesapeake Bay successfully migrated to possible breeding areas in Canada and all 13 of the black scoters migrated to suspected breeding areas. Ten of the 11 black scoter males migrated to James Bay presumably for moulting. Updated information from the ARGOS Systems aboard the NOAA satellites on scoter movements was made accessible on the Patuxent Website. Habitat cover types of locations using GIS (Geographical Information Systems) and aerial photographs (in conjunction with remote sensing software) are currently being analyzed to build thematic maps with varying cosmetic layer applications. Many factors related to human population increases have been implicated in causing changes in the distribution and abundance of wintering seaducks. Analyses of the gullet (oesophagus and proventriculus) and the gizzard of seaducks are currently being conducted to determine if changes from historical data have occurred. Scoters in the Bay feed predominantly on the hooked mussel and several species of clams. The long-tailed duck appears to select the gem clam in greater amounts than other seaducks, but exhibits a diverse diet of

  3. Atlantic CFC data in CARINA

    Directory of Open Access Journals (Sweden)

    R. Steinfeldt

    2010-01-01

    Full Text Available Water column data of carbon and carbon-relevant parameters have been collected and merged into a new database called CARINA (CARbon IN the Atlantic. In order to provide a consistent data set, all data have been examined for systematic biases and adjusted if necessary (secondary quality control (QC. The CARINA data set is divided into three regions: the Arctic/Nordic Seas, the Atlantic region and the Southern Ocean. Here we present the CFC data for the Atlantic region, including the chlorofluorocarbons CFC-11, CFC-12 and CFC-113 as well as carbon tetrachloride (CCl4. The methods applied for the secondary quality control, a crossover analyses, the investigation of CFC ratios in the ocean and the CFC surface saturation are presented. Based on the results, the CFC data of some cruises are adjusted by a certain factor or given a "poor'' quality flag.

  4. Atlantic versus Indo-Pacific influence on Atlantic-European climate

    OpenAIRE

    Pohlmann, Holger; Latif, Mojib

    2005-01-01

    The influence of the Atlantic and Indo-Pacific oceans on Atlantic-European climate is investigated by analyzing ensemble integrations with the atmospheric general circulation model ECHAM4 forced by anomalous sea surface temperature and sea ice conditions restricted to the Atlantic (AOGA) and Indo-Pacific (I+POGA) oceans. The forcing from both the Indo-Pacific and Atlantic oceans are important for the generation of the sea level pressure (SLP) variability in the Atlantic region in the boreal w...

  5. CARINA oxygen data in the Atlantic Ocean

    OpenAIRE

    Stendardo, I.; Gruber, N.; A. Körtzinger

    2009-01-01

    In the CARINA (Carbon dioxide in the Atlantic Ocean) project, a new dataset with many previously unpublished hydrographic data from the Atlantic, Arctic and Southern Ocean was assembled and subjected to careful quality control (QC) procedures. Here, we present the dissolved oxygen measurements in the Atlantic region of the dataset and describe in detail the secondary QC procedures that aim to ensure that the data are internally consistent. This is achieved by a cross-over analysis, i.e. the c...

  6. 77 FR 69596 - Atlantic Highly Migratory Species; Advisory Panel for Atlantic Highly Migratory Species Southeast...

    Science.gov (United States)

    2012-11-20

    ... but not limited to data and models, used in stock assessments for oceanic sharks in the Atlantic Ocean... assessments for oceanic sharks in the Atlantic Ocean, Gulf of Mexico, and Caribbean Sea. While the SEDAR Pool was created specifically for Atlantic oceanic sharks, it may be expanded to include other HMS,...

  7. 76 FR 65700 - Atlantic Highly Migratory Species; Advisory Panel for Atlantic Highly Migratory Species Southeast...

    Science.gov (United States)

    2011-10-24

    ..., used in stock assessments for oceanic sharks in the Atlantic Ocean, Gulf of Mexico, and Caribbean Sea... sharks in the Atlantic Ocean, Gulf of Mexico, and Caribbean Sea. While the SEDAR Pool was created specifically for Atlantic oceanic sharks, it may be expanded to include other HMS, as needed. The...

  8. 75 FR 57698 - Atlantic Highly Migratory Species; Atlantic Billfish Management, White Marlin (Kajikia albidus

    Science.gov (United States)

    2010-09-22

    ... western Atlantic Ocean, white marlin and blue marlin from the North Atlantic Ocean, and longbill spearfish... published an interim rule (63 FR 14030) that increased the minimum size limits for Atlantic blue marlin and... Consolidated HMS FMP (71 FR 58058), which, among other things, included the annual recreational 250 blue...

  9. Evidence for a bimodal distribution of hybrid indices in a hybrid zone with high admixture.

    Science.gov (United States)

    McKenzie, Jessica L; Dhillon, Rashpal S; Schulte, Patricia M

    2015-12-01

    The genetic structure of a hybrid zone can provide insights into the relative roles of the various factors that maintain the zone. Here, we use a multilocus approach to characterize a hybrid zone between two subspecies of killifish (Fundulus heteroclitus, Walbaum 1792) found along the Atlantic coast of North America. We first analysed clinal variation along the Atlantic coast using a single-nucleotide polymorphism in the mitochondrial DNA (mtDNA) displacement loop (D-loop) and a panel of nine nuclear microsatellite markers. A model constraining all clines to the same width and centre was not significantly different from a model in which the clines were allowed to vary independently. Locus-by-locus analysis indicated that the majority of nuclear clines shared the same centre as the mtDNA cline, and the widths of these clines were also narrower than that predicted by a neutral model, suggesting that selection is operating to maintain the hybrid zone. However, two of the nuclear clines had widths greater than the neutral prediction and had centres that were displaced relative to the mtDNA cline centre. We also found that a marsh located near the centre of the mtDNA cline demonstrated a bimodal distribution of nuclear hybrid index values, suggesting a deficit of first-generation hybrids and backcrossed genotypes. Thus, selection against hybrid genotypes may be playing a role in maintaining this hybrid zone and the associated steep nuclear and mtDNA clines. PMID:27019720

  10. 22 CFR 120.31 - North Atlantic Treaty Organization.

    Science.gov (United States)

    2010-04-01

    ... DEFINITIONS § 120.31 North Atlantic Treaty Organization. North Atlantic Treaty Organization (NATO) is..., France, Germany, Greece, Hungary, Iceland, Italy, Latvia, Lithuania, Luxembourg, The Netherlands,...

  11. Atlantic hurricane response to geoengineering

    Science.gov (United States)

    Moore, John; Grinsted, Aslak; Ji, Duoying; Yu, Xiaoyong; Guo, Xiaoran

    2015-04-01

    Devastating Atlantic hurricanes are relatively rare events. However their intensity and frequency in a warming world may rapidly increase - perhaps by a factor of 5 for a 2°C mean global warming. Geoengineering by sulphate aerosol injection preferentially cools the tropics relative to the polar regions, including the hurricane main development region in the Atlantic, suggesting that geoengineering may be an effective method of controlling hurricanes. We examine this hypothesis using 6 Earth System Model simulations of climate under the GeoMIP G3 and G4 schemes that use aerosols to reduce the radiative forcing under the RCP4.5 scenario. We find that although temperatures are ameliorated by geoengineering, the numbers of storm surge events as big as that caused the 2005 Katrina hurricane are only slightly reduced compared with no geoengineering. As higher levels of sulphate aerosol injection produce diminishing returns in terms of cooling, but cause undesirable effects in various regions, it seems that stratospheric aerosol geoengineering is not an effective method of controlling hurricane damage.

  12. Temperature fluctuations in the Atlantic Ocean

    International Nuclear Information System (INIS)

    The article discusses the temperature fluctuations in connection with drought in Africa, the climate in North America, the European heat waves and the frequent tropical hurricanes in the Atlantic Ocean. Problems with climate modelling and some pollution aspects are mentioned

  13. Atlantic Marine Mammal Assessment Vessel Surveys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data sets are a compilation of large vessel surveys for marine mammal stock assessments in South Atlantic (Florida to Maryland) waters from 1994 to the...

  14. Atlantic energy and the strategic outlook

    Directory of Open Access Journals (Sweden)

    Paul Isbell

    2013-09-01

    Full Text Available Sweeping changes are beginning to transform energy scenarios around the world. The gas revolution, a renaissance in petroleum technology and exploration, and a chaotic but powerful movement toward the goal of low-carbon economies are three of the principal energy trends currently interacting with structural changes in the geo-economics of the Atlantic world to present new perspectives and opportunitiesfor the diverse actors in the ‘Atlantic Basin’. This article explores how changes in the energy landscape are contributing to a reassessment of the strategic horizon. The potential impacts of the shale revolution, deep-offshore oil, biofuels and other modern renewable energies on the geopolitics of the Atlantic Basin will be assessed, and the hypothesis that an Atlantic Basin energy system is now taking shape will be evaluated, along with an analysis of anticipated impacts.

  15. Northwest Atlantic Regional Climatology (NCEI Accession 0155889)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To provide an improved oceanographic foundation and reference for multi-disciplinary studies of the Northwest Atlantic Ocean, NCEI Regional Climatology Team...

  16. Ocean science: Vagaries of Atlantic overturning

    Science.gov (United States)

    Haine, Thomas W. N.

    2016-07-01

    A weakening of the Atlantic meridional overturning circulation has emerged from noise after years of painstaking measurements. Three independent lines of evidence suggest that an anthropogenic influence on this overturning is not yet detectable.

  17. Atlantic NAD 83 Continental Shelf Boundary (CSB)

    Data.gov (United States)

    Bureau of Ocean Energy Management, Department of the Interior — This data set contains Continental Shelf Boundary (CSB) lines in ESRI shapefile format for the BOEM Atlantic Region. The CSB defines the seaward limit of federally...

  18. Atlantic NAD 83 SLA Baseline Tangents

    Data.gov (United States)

    Bureau of Ocean Energy Management, Department of the Interior — This data set contains baseline tangent lines in ArcGIS shapefile format for the BOEM Atlantic Region. Baseline tangent lines are typically bay or river closing...

  19. Atlantic NAD 83 SLA Baseline Points

    Data.gov (United States)

    Bureau of Ocean Energy Management, Department of the Interior — This data set contains baseline points in ArcGIS shapefile format for the BOEM Atlantic Region. Baseline points are the discrete coordinate points along the...

  20. Atlantic Sharpnose Shark Reproductive Biology Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Reproductive data from Atlantic sharpnose sharks were collected from specimens captured throughout the northern Gulf of Mexico on various research vessels. Data...

  1. North Atlantic Coastal Plain aquifer system

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set represents the extent of the North Atlantic Coastal Plain aquifer system in North Carolina, Virginia, Maryland, Deleware, and New Jersey.

  2. Atlantic Surfclam and Ocean Quahog Survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The standardized NEFSC Atlantic Surfclam and Ocean Quahog Survey has covered an area from Cape Hatteras to Georges Bank. The survey was conducted every two or three...

  3. 75 FR 11133 - Fisheries of the South Atlantic; South Atlantic Fishery Management Council; Public Meeting

    Science.gov (United States)

    2010-03-10

    ... Wreckfish Shareholders for the South Atlantic region to discuss draft Amendment 20 to the Snapper Grouper... Shareholders for the South Atlantic region. See SUPPLEMENTARY INFORMATION. DATES: The meeting will take place... Wreckfish Shareholders on changes the Council is considering for the current ITQ program in Amendment 20...

  4. 78 FR 65974 - Atlantic Highly Migratory Species; Advisory Panel for Atlantic Highly Migratory Species Southeast...

    Science.gov (United States)

    2013-11-04

    ... not limited to data and models, used in stock assessments for oceanic sharks in the Atlantic Ocean... information, including but not limited to data and models, used in stock assessments for oceanic sharks in the... Atlantic oceanic sharks, it may be expanded to include other HMS, as needed. The primary purpose of...

  5. Response of the Atlantic overturning circulation to South Atlantic sources of buoyancy

    NARCIS (Netherlands)

    Weijer, W.; Ruijter, W.P.M. de; Sterl, A.; Drijfhout, S.

    2002-01-01

    The heat and salt input from the Indian to Atlantic Oceans by Agulhas Leakage is found to influence the Atlantic overturning circulation in a low-resolution Ocean General Circulation Model. The model used is the Hamburg Large-Scale Geostrophic (LSG) model, which is forced by mixed boundary condition

  6. 77 FR 35357 - Atlantic Highly Migratory Species; Commercial Atlantic Region Non-Sandbar Large Coastal Shark...

    Science.gov (United States)

    2012-06-13

    ...-Stevens Fishery Conservation and Management Act (16 U.S.C. 1801 et seq.). On January 24, 2012 (77 FR 3393... rule implementing the Atlantic HMS electronic dealer ] reporting system (76 FR 37750; June 28, 2011) or...; Commercial Atlantic Region Non-Sandbar Large Coastal Shark Fishery Opening Date AGENCY: National...

  7. 77 FR 61562 - Atlantic Highly Migratory Species; 2013 Atlantic Shark Commercial Fishing Season

    Science.gov (United States)

    2012-10-10

    ... accompanied the 2011 shark quota specifications rule (75 FR 76302; December 8, 2010). Thus, NMFS proposes to... Species; 2013 Atlantic Shark Commercial Fishing Season AGENCY: National Marine Fisheries Service (NMFS... season for the Atlantic commercial shark fisheries. Quotas would be adjusted as allowable based on...

  8. 76 FR 57709 - Atlantic Highly Migratory Species; Atlantic Shark Management Measures

    Science.gov (United States)

    2011-09-16

    .... As outlined in the September 20, 2010, ANPR (75 FR 57235), sharks have been federally managed since... Species; Atlantic Shark Management Measures AGENCY: National Marine Fisheries Service (NMFS), National... Atlantic shark landings; request for comments. SUMMARY: This notice announces the National Marine...

  9. Qualitative community stability determines parasite establishment and richness in estuarine marshes

    OpenAIRE

    Tavis K Anderson; Sukhdeo, Michael V. K.

    2013-01-01

    The establishment of parasites with complex life cycles is generally thought to be regulated by free-living species richness and the stability of local ecological interactions. In this study, we test the prediction that stable host communities are prerequisite for the establishment of complex multi-host parasite life cycles. The colonization of naïve killifish, Fundulus heteroclitus, by parasites was investigated in 4 salt marsh sites that differed in time since major ecological restoration, ...

  10. Kinematics of the South Atlantic rift

    Directory of Open Access Journals (Sweden)

    C. Heine

    2013-01-01

    Full Text Available The South Atlantic rift basin evolved as branch of a large Jurassic-Cretaceous intraplate rift zone between the African and South American plates during the final breakup of western Gondwana. While the relative motions between South America and Africa for post-breakup times are well resolved, many issues pertaining to the fit reconstruction and particular the relation between kinematics and lithosphere dynamics during pre-breakup remain unclear in currently published plate models. We have compiled and assimilated data from these intraplated rifts and constructed a revised plate kinematic model for the pre-breakup evolution of the South Atlantic. Based on structural restoration of the conjugate South Atlantic margins and intracontinental rift basins in Africa and South America, we achieve a tight fit reconstruction which eliminates the need for previously inferred large intracontinental shear zones, in particular in Patagonian South America. By quantitatively accounting for crustal deformation in the Central and West African rift zone, we have been able to indirectly construct the kinematic history of the pre-breakup evolution of the conjugate West African-Brazilian margins. Our model suggests a causal link between changes in extension direction and velocity during continental extension and the generation of marginal structures such as the enigmatic Pre-salt sag basin and the São Paulo High. We model an initial E–W directed extension between South America and Africa (fixed in present-day position at very low extensional velocities until Upper Hauterivian times (≈126 Ma when rift activity along in the equatorial Atlantic domain started to increase significantly. During this initial ≈17 Myr-long stretching episode the Pre-salt basin width on the conjugate Brazilian and West African margins is generated. An intermediate stage between 126.57 Ma and Base Aptian is characterised by strain localisation, rapid lithospheric weakening in the

  11. Atlantic reef fish biogeography and evolution

    Science.gov (United States)

    Floeter, S.R.; Rocha, L.A.; Robertson, D.R.; Joyeux, J.C.; Smith-Vaniz, W.F.; Wirtz, P.; Edwards, A.J.; Barreiros, J.P.; Ferreira, C.E.L.; Gasparini, J.L.; Brito, A.; Falcon, J.M.; Bowen, B.W.; Bernardi, G.

    2008-01-01

    Aim: To understand why and when areas of endemism (provinces) of the tropical Atlantic Ocean were formed, how they relate to each other, and what processes have contributed to faunal enrichment. Location: Atlantic Ocean. Methods: The distributions of 2605 species of reef fishes were compiled for 25 areas of the Atlantic and southern Africa. Maximum-parsimony and distance analyses were employed to investigate biogeographical relationships among those areas. A collection of 26 phylogenies of various Atlantic reef fish taxa was used to assess patterns of origin and diversification relative to evolutionary scenarios based on spatio-temporal sequences of species splitting produced by geological and palaeoceanographic events. We present data on faunal (species and genera) richness, endemism patterns, diversity buildup (i.e. speciation processes), and evaluate the operation of the main biogeographical barriers and/or filters. Results: Phylogenetic (proportion of sister species) and distributional (number of shared species) patterns are generally concordant with recognized biogeographical provinces in the Atlantic. The highly uneven distribution of species in certain genera appears to be related to their origin, with highest species richness in areas with the greatest phylogenetic depth. Diversity buildup in Atlantic reef fishes involved (1) diversification within each province, (2) isolation as a result of biogeographical barriers, and (3) stochastic accretion by means of dispersal between provinces. The timing of divergence events is not concordant among taxonomic groups. The three soft (non-terrestrial) inter-regional barriers (mid-Atlantic, Amazon, and Benguela) clearly act as 'filters' by restricting dispersal but at the same time allowing occasional crossings that apparently lead to the establishment of new populations and species. Fluctuations in the effectiveness of the filters, combined with ecological differences among provinces, apparently provide a mechanism

  12. Nitrous oxide in the North Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    S. Walter

    2006-01-01

    Full Text Available In order to get a comprehensive picture of the distribution of nitrous oxide (N2O in the North Atlantic Ocean, measurements of dissolved nitrous oxide were made during three cruises in the tropical, subtropical and cold-temperate North Atlantic Ocean in October/November 2002, March/April 2004, and May 2002, respectively. To account for the history of atmospheric N2O, we suggest a new depth-dependent calculation of excess N2O (ΔN2O. N2O depth profiles showed supersaturation throughout the water column with a distinct increasing trend from the cold-temperate to the tropical region. Lowest nitrous oxide concentrations, near equilibrium and with an average of 11.0±1.7 nmol L−1, were found in the cold-temperate North Atlantic where the profiles showed no clear maxima. Highest values up to 37.3 nmol L−1 occurred in the tropical North Atlantic with clear maxima at approximately 400 m. A positive correlation of nitrous oxide with nitrate, as well as excess nitrous oxide with the apparent oxygen utilization (AOU, was only observed in the subtropical and tropical regions. Therefore, we conclude that the formation of nitrous oxide via nitrification occurs in the tropical region rather than in the cold-temperate region of the North Atlantic Ocean

  13. Evolutionary diversity among Atlantic coast mangroves

    Science.gov (United States)

    Dodd, Richard S.; Rafii, Zara A.; Fromard, François; Blasco, François

    1998-06-01

    Current knowledge of intraspecific variation of mangrove species is limited in terms of rangewide distributions and is mostly restricted to morphological analyses, which have indicated a high degree of homogeneity. However, our analyses of the aliphatic hydrocarbon and triterpenoid fraction of foliar waxes (by gas chromatography and mass spectroscopy) of mangrove species ( Rhizophora mangle, Avicennia germinans and Laguncularia racemosa) from Gabon in West Africa and French Guiana in South America show significant genetic differentiation between eastern and western Atlantic provenances. The greater diversity in lipid composition, and the tendency for longer carbon chain lengths in all taxa from Africa, may suggest that American mangroves exhibit derived characteristics. A consequence of this hypothesis would be that Atlantic mangroves are unlikely to have dispersed from the Tethys via the Pacific, as has been proposed by some authors. More widespread sampling within the Atlantic and east Pacific region is needed to support and confirm these results.

  14. CARINA alkalinity data in the Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    A. Velo

    2009-08-01

    Full Text Available Data on carbon and carbon-relevant hydrographic and hydrochemical parameters from previously non-publicly available cruise data sets in the Arctic, Atlantic and Southern Ocean have been retrieved and merged to a new database: CARINA (CARbon IN the Atlantic.

    These data have gone through rigorous quality control (QC procedures to assure the highest possible quality and consistency. The data for most of the measured parameters in the CARINA data base were objectively examined in order to quantify systematic differences in the reported values, i.e. secondary quality control. Systematic biases found in the data have been corrected in the data products, i.e. three merged data files with measured, calculated and interpolated data for each of the three CARINA regions; Arctic, Atlantic and Southern Ocean. Out of a total of 188 cruise entries in the CARINA database, 98 were conducted in the Atlantic Ocean and of these, 75 cruises report alkalinity values.

    Here we present details of the secondary QC on alkalinity for the Atlantic Ocean part of CARINA. Procedures of quality control, including crossover analysis between cruises and inversion analysis of all crossover data are briefly described. Adjustments were applied to the alkalinity values for 16 of the cruises in the Atlantic Ocean region. With these adjustments the CARINA database is consistent both internally as well as with GLODAP data, an oceanographic data set based on the World Hydrographic Program in the 1990s. Based on our analysis we estimate the internal accuracy of the CARINA-ATL alkalinity data to be 3.3 μmol kg−1. The CARINA data are now suitable for accurate assessments of, for example, oceanic carbon inventories and uptake rates and for model validation.

  15. CARINA: nutrient data in the Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    T. Tanhua

    2009-07-01

    Full Text Available Data on carbon and carbon-relevant hydrographic and hydrochemical parameters from previously non-publicly available cruise data sets in the Arctic, Atlantic and Southern Ocean have been retrieved and merged to a new database: CARINA (CARbon IN the Atlantic. These data have gone through rigorous quality control (QC procedures to assure the highest possible quality and consistency. The data for most of the measured parameters in the CARINA data base were objectively examined in order to quantify systematic differences in the reported values, i.e. secondary quality control. Systematic biases found in the data have been corrected in the data products, i.e. three merged data files with measured, calculated and interpolated data for each of the three CARINA regions; Arctic, Atlantic and Southern Ocean. Out of a total of 188 cruise entries in the CARINA database, 98 were conducted in the Atlantic Ocean and of these 84 cruises report nitrate values, 79 silicate, and 78 phosphate. Here we present details of the secondary QC for nutrients for the Atlantic Ocean part of CARINA. Procedures of quality control, including crossover analysis between cruises and inversion analysis of all crossover data are briefly described. Adjustments were applied to the nutrient values for 43 of the cruises in the Atlantic Ocean region. With these adjustments the CARINA database is consistent both internally as well as with GLODAP data, an oceanographic data set based on the World Hydrographic Program in the 1990s (Key et al., 2004. Based on our analysis we estimate the internal accuracy of the CARINA-ATL nutrient data to be: nitrate 1.5%; phosphate 2.6%; silicate 3.1%. The CARINA data are now suitable for accurate assessments of, for example, oceanic carbon inventories and uptake rates and for model validation.

  16. Correcting North Atlantic sea surface salinity biases in the Kiel Climate Model: influences on ocean circulation and Atlantic Multidecadal Variability

    Science.gov (United States)

    Park, T.; Park, W.; Latif, M.

    2016-10-01

    A long-standing problem in climate models is the large sea surface salinity (SSS) biases in the North Atlantic. In this study, we describe the influences of correcting these SSS biases on the circulation of the North Atlantic as well as on North Atlantic sector mean climate and decadal to multidecadal variability. We performed integrations of the Kiel Climate Model (KCM) with and without applying a freshwater flux correction over the North Atlantic. The quality of simulating the mean circulation of the North Atlantic Ocean, North Atlantic sector mean climate and decadal variability is greatly enhanced in the freshwater flux-corrected integration which, by definition, depicts relatively small North Atlantic SSS biases. In particular, a large reduction in the North Atlantic cold sea surface temperature bias is observed and a more realistic Atlantic Multidecadal Variability simulated. Improvements relative to the non-flux corrected integration also comprise a more realistic representation of deep convection sites, sea ice, gyre circulation and Atlantic Meridional Overturning Circulation. The results suggest that simulations of North Atlantic sector mean climate and decadal variability could strongly benefit from alleviating sea surface salinity biases in the North Atlantic, which may enhance the skill of decadal predictions in that region.

  17. 75 FR 27219 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

    Science.gov (United States)

    2010-05-14

    ... United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications...), Commerce. ACTION: Final rule. SUMMARY: NMFS issues final specifications for the 2010 Atlantic deep- sea red... document is also accessible via the Internet at http://www.nefmc.org . NMFS prepared a Final...

  18. 76 FR 23935 - Atlantic Highly Migratory Species; Atlantic Shark Management Measures

    Science.gov (United States)

    2011-04-29

    ... or hammerhead sharks in the Coastal Fisheries Logbook. Currently, there is no commercial oceanic... Species; Atlantic Shark Management Measures AGENCY: National Marine Fisheries Service (NMFS), National... published in the Federal Register (71 FR 58058) final regulations, effective November 1, 2006...

  19. 78 FR 4129 - Fisheries of the South Atlantic; South Atlantic Fishery Management Council; Public Meetings

    Science.gov (United States)

    2013-01-18

    ... System (VMS), as well as a review of the VMS fact sheet. 2. Receive a presentation on the mobile phone... VMS requirements for vessels with South Atlantic commercial snapper grouper permits. This action...

  20. 78 FR 11809 - Fisheries of the Northeastern United States; Atlantic Bluefish Fishery; 2013-2014 Atlantic...

    Science.gov (United States)

    2013-02-20

    .... Christopher M. Moore, Executive Director, Mid-Atlantic Fishery Management Council, Suite 201, 800 N. State... overfishing. Authority: 16 U.S.C. 1801 et seq. Dated: February 12, 2013. Alan D. Risenhoover, Director,...

  1. 77 FR 8776 - Fisheries of the Northeastern United States; Atlantic Bluefish Fishery; 2012 Atlantic Bluefish...

    Science.gov (United States)

    2012-02-15

    .... Moore, Executive Director, Mid-Atlantic Fishery Management Council, Suite 201, 800 N. State Street... Monitoring Committee. Authority: 16 U.S.C. 1801 et seq. Dated: February 9, 2012. Alan D. Risenhoover,...

  2. Response of the South Atlantic circulation to an abrupt collapse of the Atlantic meridional overturning circulation

    Energy Technology Data Exchange (ETDEWEB)

    Laurian, Audine [University of Hawai' i at Manoa, International Pacific Research Center, School of Ocean and Earth Science and Technology, Honolulu, HI (United States); Drijfhout, Sybren S. [Royal Netherlands Meteorological Institute, De Bilt (Netherlands)

    2011-08-15

    The South Atlantic response to a collapse of the North Atlantic meridional overturning circulation (AMOC) is investigated in the ECHAM5/MPI-OM climate model. A reduced Agulhas leakage (about 3.1 Sv; 1 Sv = 10{sup 6} m{sup 3} s{sup -1}) is found to be associated with a weaker Southern Hemisphere (SH) supergyre and Indonesian throughflow. These changes are due to reduced wind stress curl over the SH supergyre, associated with a weaker Hadley circulation and a weaker SH subtropical jet. The northward cross-equatorial transport of thermocline and intermediate waters is much more strongly reduced than Agulhas leakage in relation with an AMOC collapse. A cross-equatorial gyre develops due to an anomalous wind stress curl over the tropics that results from the anomalous sea surface temperature gradient associated with reduced ocean heat transport. This cross-equatorial gyre completely blocks the transport of thermocline waters from the South to the North Atlantic. The waters originating from Agulhas leakage flow somewhat deeper and most of it recirculates in the South Atlantic subtropical gyre, leading to a gyre intensification. This intensification is consistent with the anomalous surface cooling over the South Atlantic. Most changes in South Atlantic circulation due to global warming, featuring a reduced AMOC, are qualitatively similar to the response to an AMOC collapse, but smaller in amplitude. However, the increased northward cross-equatorial transport of intermediate water relative to thermocline water is a strong fingerprint of an AMOC collapse. (orig.)

  3. Population structure of Atlantic Mackerel (Scomber scombrus)

    DEFF Research Database (Denmark)

    Jansen, Teunis; Gislason, Henrik

    2013-01-01

    model where the population structure of mackerel is described as a dynamic cline, rather than as connected contingents. Temporal changes in hydrography and mackerel behavior may affect the steepness of the cline at various locations. The new interpretation of the population structure of Atlantic...

  4. Indian - Atlantic interocean exchange: variability and controls

    NARCIS (Netherlands)

    Schouten, Mathijs Wilhelmus

    2003-01-01

    South of Africa, warm Indian Ocean water enters the Atlantic Ocean by means of large Agulhas Rings. These rings, with diameters up to 350 km and reaching all the way to the ocean floor at 5 km depth, form an important link in the global thermohaline circulation, which is the driving force behind the

  5. Coccolithophores in the equatorial Atlantic Ocean

    DEFF Research Database (Denmark)

    Kinkel, Hanno; Baumann, K.-H.; Cepek, M.

    2000-01-01

    The present study was initiated to ascertain the significance of coccolithophores as a proxy for paleoceanographic and paleoproductivity studies in the equatorial Atlantic. Data from a range of different samples, from the plankton, surface sediments as well as sediment cores are shown and compare...

  6. Atlantic and indian oceans pollution in africa

    Science.gov (United States)

    Abubakar, Babagana

    Africa is the second largest and most populated continent after Asia. Geographically it is located between the Atlantic and Indian Oceans. Most of the Africa's most populated and industrialized cities are located along the coast of the continent facing the Atlantic and Indian Oceans, example of such cities include Casablanca, Dakar, Accra, Lagos, Luanda and Cape town all facing the Atlantic Ocean and cities like East London, Durban, Maputo, Dar-es-salaam and Mogadishu are all facing the Indian Ocean. As a result of the geographical locations of African Coastal Cities plus increase in their population, industries, sea port operations, petroleum exploration activities, trafficking of toxic wastes and improper waste management culture lead to the incessant increase in the pollution of the two oceans. NATURE OF POLLUTION OF THE ATLANTIC OCEAN i. The petroleum exploration activities going on along the coast of "Gulf of Guinea" region and Angola continuously causes oil spillages in the process of drilling, bunkering and discharging of petroleum products in the Atlantic Ocean. ii. The incessant degreasing of the Sea Ports "Quay Aprons" along the Coastal cities of Lagos, Luanda, Cape Town etc are continuously polluting the Atlantic Ocean with chemicals. iii. Local wastes generated from the houses located in the coastal cities are always finding their ways into the Atlantic Ocean. NATURE OF POLLUTION OF THE INDIAN OCEAN i. Unlike the Atlantic ocean where petroleum is the major pollutant, the Indian Ocean is polluted by Toxic / Radioactive waste suspected to have been coming from the developed nations as reported by the United Nations Environmental Programme after the Tsunami disaster in December 2004 especially along the coast of Somalia. ii. The degreasing of the Quay Aprons at Port Elizabeth, Maputo, Dar-es-Salaam and Mongolism Sea Ports are also another major source polluting the Indian Ocean. PROBLEMS GENERATED AS A RESULT OF THE OCEANS POLLUTION i. Recent report

  7. AtlantOS - Optimizing and Enhancing the Integrated Atlantic Ocean Observing System

    Science.gov (United States)

    Reitz, Anja; Visbeck, Martin; AtlantOS Consortium, the

    2016-04-01

    Atlantic Ocean observation is currently undertaken through loosely-coordinated, in-situ observing networks, satellite observations and data management arrangements of heterogeneous international, national and regional design to support science and a wide range of information products. Thus there is tremendous opportunity to develop the systems towards a fully integrated Atlantic Ocean Observing System consistent with the recently developed 'Framework of Ocean Observing'. The vision of AtlantOS is to improve and innovate Atlantic observing by using the Framework of Ocean Observing to obtain an international, more sustainable, more efficient, more integrated, and fit-for-purpose system. Hence, the AtlantOS initiative will have a long-lasting and sustainable contribution to the societal, economic and scientific benefit arising from this integrated approach. This will be delivered by improving the value for money, extent, completeness, quality and ease of access to Atlantic Ocean data required by industries, product supplying agencies, scientist and citizens. The overarching target of the AtlantOS initiative is to deliver an advanced framework for the development of an integrated Atlantic Ocean Observing System that goes beyond the state-of -the-art, and leaves a legacy of sustainability after the life of the project. The legacy will derive from the following aims: i) to improve international collaboration in the design, implementation and benefit sharing of ocean observing, ii) to promote engagement and innovation in all aspects of ocean observing, iii) to facilitate free and open access to ocean data and information, iv) to enable and disseminate methods of achieving quality and authority of ocean information, v) to strengthen the Global Ocean Observing System (GOOS) and to sustain observing systems that are critical for the Copernicus Marine Environment Monitoring Service and its applications and vi) to contribute to the aims of the Galway Statement on Atlantic

  8. Displaced fracture through the anterior atlantal synchondrosis

    Energy Technology Data Exchange (ETDEWEB)

    Thakar, Chrishan; Allibone, James [Royal National Orthopaedic Hospital NHS Trust, Department of Spinal Deformity, Stanmore, Middlesex (United Kingdom); Harish, Srinivasan [Royal National Orthopaedic Hospital NHS Trust, Department of Radiology, Stanmore, Middlesex (United Kingdom); Saifuddin, Asif [Royal National Orthopaedic Hospital NHS Trust, Department of Radiology, Stanmore, Middlesex (United Kingdom); University College, The Institute of Orthopaedics and Musculoskeletal Sciences, London (United Kingdom)

    2005-09-01

    In the acute setting, accurate radiological interpretation of paediatric cervical spine trauma can be difficult due to a combination of normal variants and presence of multiple synchondroses. We present a rare case of a fracture through the anterior atlantal synchondrosis in a paediatric spine. A five-year-old boy, who fell backwards onto the top of his head while swinging across on a monkey bar frame, presented with neck pain, cervical muscle spasm and decreased right lateral rotation and extension of his neck. Computed tomography showed a displaced diastatic fracture through right anterior atlantal synchondrosis. There are only 12 cases of paediatric C1 fractures reported in the world literature. The importance of considering this diagnosis in the appropriate clinical setting, and the normal variants in the paediatric atlas that can cause diagnostic dilemma to the interpreting radiologist, are discussed in this case report. (orig.)

  9. Wind Stress Increases Glacial Atlantic Overturning

    Science.gov (United States)

    Muglia, J.; Schmittner, A.

    2015-12-01

    Previous Paleoclimate Model Intercomparison Project (PMIP) simulations of the Last Glacial Maximum (LGM) Atlantic Meridional Overturning Circulation (AMOC) showed ambiguous results on transports and structure. Here we analyze the most recent PMIP3 models, which show a consistent increase (on average by 41%) and deepening (580 m) of the AMOC for all models with respect to pre-industrial control (PIC) simulations (see Figure), in contrast to some reconstructions. Changes in wind stress alone lead to similar AMOC responses in a climate-ocean circulation model, suggesting that atmospheric circulation changes in the North Atlantic due to the presence of ice sheets are an important control in the PMIP3 models' LGM response. These results improve our understanding of the LGM AMOC's driving forces and are relevant for the evaluation of models that are used in the IPCC's Assessment Reports for future climate projections, as well as for the currently ongoing design of the next round of PMIP.

  10. Coherent water transport across the South Atlantic

    CERN Document Server

    Wang, Y; Beron-Vera, F J

    2015-01-01

    The role of mesoscale eddies in transporting Agulhas leakage is investigated using a recent technique from nonlinear dynamical systems theory applied on geostrophic currents inferred from the over two-decade-long satellite altimetry record. Eddies are found to acquire material coherence away from the Agulhas retroflection, near the Walvis Ridge in the South Atlantic. Yearly, 1 to 4 coherent material eddies are detected with diameters ranging from 40 to 280 km. A total of 23 eddy cores of about 50 km in diameter and with at least 30% of their contents traceable into the Indian Ocean were found to travel across the subtropical gyre with minor filamentation. No more than 5\\% of such cores pour their contents on the North Brazil Current. While ability of eddies to carry Agulhas leakage northwestward across the South Atlantic is supported by our analysis, this is more restricted than suggested by earlier ring transport assessments.

  11. Modes of winter precipitation variability in the North Atlantic

    Energy Technology Data Exchange (ETDEWEB)

    Zorita, E. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Hydrophysik; Saenz, J.; Fernandez, J.; Zubillaga, J. [Bilbao Univ. (Spain)

    2001-07-01

    The modes of variability of winter precipitation in the North Atlantic sector are identified by Empirical Orthogonal Functions Analysis in the NCEP/NCAR global reanalysis data sets. These modes are also present in a gridded precipitation data set over the Western Europe. The large-scale fields of atmospheric seasonal mean circulation, baroclinic activity, evaporation and humidity transport that are connected to the rainfall modes have been also analyzed in order to investigate the physical mechanisms that are causally linked to the rainfall modes. The results indicate that the leading rainfall mode is associated to the North Atlantic oscillation and represents a meridional redistribution of precipitation in the North Atlantic through displacements of the storm tracks. The second mode is related to evaporation anomalies in the Eastern Atlantic that precipitate almost entirely in the Western Atlantic. The third mode seems to be associated to meridional transport of water vapor from the Tropical Atlantic. (orig.)

  12. Indian - Atlantic interocean exchange: variability and controls

    OpenAIRE

    Schouten, Mathijs Wilhelmus

    2003-01-01

    South of Africa, warm Indian Ocean water enters the Atlantic Ocean by means of large Agulhas Rings. These rings, with diameters up to 350 km and reaching all the way to the ocean floor at 5 km depth, form an important link in the global thermohaline circulation, which is the driving force behind the moderate temperatures over Northern Europe. For six years, the shedding of Agulhas rings has been monitored from space, using satellite altimeter measurements of the sea surface height. Rings can ...

  13. Fisheries. Population of origin of Atlantic cod.

    Science.gov (United States)

    Nielsen, E E; Hansen, M M; Schmidt, C; Meldrup, D; Grønkjaer, P

    2001-09-20

    Most of the world's cod (Gadus morhua) fisheries are now tightly regulated or closed altogether. Being able to link individual fish to their population of origin would assist enormously in policing regulations and in identifying poachers. Here we show that microsatellite genetic markers can be used to assign individual cod from three different populations in the northeastern Atlantic Ocean to their population of origin. PMID:11565021

  14. In Brief: Atlantic seasonal hurricane forecast

    Science.gov (United States)

    Showstack, Randy

    2007-12-01

    Two hurricane forecasters are predicting that 2008 will be an above-average Atlantic basin tropical cyclone season with an above-average probability of a major hurricane making landfall in the United States. During 2008, there could be about seven hurricanes (the annual average is 5.9) and 13 named storms (the average is 9.6), according to a 7 December report by Philip Klotzbach, research scientist at Colorado State University in Fort Collins, and William Gray, university professor emeritus of atmospheric sciences. The forecasters indicate that they believe the Atlantic basin is in an active hurricane cycle that is associated with a strong thermohaline circulation and an active phase of the Atlantic Multidecadal Oscillation. The report notes that, ``real-time operational early December forecasts have not shown forecast skill over climatology during this 16-year period [1992-2007]. This has occurred despite the fact that the skill over the hindcast period...showed appreciable skill.'' For more information, visit the Web site: http://hurricane.atmos.colostate.edu/Forecasts/2007/dec2007/dec2007.pdf.

  15. Local and remote impacts of a tropical Atlantic salinity anomaly

    OpenAIRE

    Mignot, Juliette; Frankignoul, Claude

    2009-01-01

    The climatic impacts of an enhanced evaporation prescribed during 50 years in the tropical Atlantic are investigated in a coupled ocean-atmosphere general circulation model. Locally, the salinity increase leads to a rapid deepening and cooling of the surface mixed layer. This induces a deepening of the equatorial undercurrent and an intensification of the south equatorial current. A remote atmospheric response to the tropical Atlantic perturbation is detected in the North Atlantic sector afte...

  16. Mechanisms and predictability of North Atlantic - European Climate

    OpenAIRE

    Pohlmann, H.

    2005-01-01

    This study investigates the mechanisms of North Atlantic-European climate using atmosphere general circulation models (AGCMs). Experiments with the AGCM ECHAM4, in which the sea surface temperature (SST) forcing is restricted to either the Atlantic or the Indo-Pacific oceans, show that both oceanic regions have an influence on North Atlantic-European climate in winter. In the experiment with SST forcing restricted to the Indo-Pacific oceans the atmospheric response projects on the North Atlan...

  17. Evidence of remote forcing in the Equatorial Atlantic ocean

    OpenAIRE

    Servain, J.; Picaut, Joël; Merle, Jacques

    1982-01-01

    An analysis of sea-surface temperature (STT) and surface winds in selected areas of the Tropical Atlantic indicates that the nonseasonal variability of SST in the Eastern Equatorial Atlantic (Gulf of Guinea) is highly correlated with the nonseasonal variability of the zonal wind stress in the Western Equatorial Atlantic. A negative (positive) anomaly of the zonal wind stress near the North Brazilian coast is followed by a positive (negative) SST anomaly in the Gulf of Guinea about one month l...

  18. NEFSC 2010 Atlantic Herring Acoustic/Midwater Trawl Survey (DE1010, EK60)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NEFSC Atlantic herring acoustic survey is a fisheries independent survey that provides scientific data for Atlantic herring assessments in the U.S. mid-Atlantic...

  19. 75 FR 9158 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; Coastal Sharks Fishery

    Science.gov (United States)

    2010-03-01

    ... National Oceanic and Atmospheric Administration RIN 0648-XU54 Atlantic Coastal Fisheries Cooperative Management Act Provisions; Coastal Sharks Fishery AGENCY: National Marine Fisheries Service (NMFS), National... provisions of the Atlantic Coastal Fisheries Cooperative Management Act (Atlantic Coastal Act). The...

  20. 75 FR 33242 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; Weakfish Fishery

    Science.gov (United States)

    2010-06-11

    ... National Oceanic and Atmospheric Administration RIN 0648-XW45 Atlantic Coastal Fisheries Cooperative Management Act Provisions; Weakfish Fishery AGENCY: National Marine Fisheries Service (NMFS), National... the provisions of the Atlantic Coastal Fisheries Cooperative Management Act (Atlantic Coastal...

  1. NEFSC 1999 Atlantic Herring Acoustic/Midwater Trawl Survey (DE9909, EK500)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NEFSC Atlantic herring acoustic survey is a fisheries independent survey that provides scientific data for Atlantic herring assessments in the U.S. mid-Atlantic...

  2. NEFSC 2008 Atlantic Herring Acoustic/Midwater Trawl Survey (DE0809, EK500)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NEFSC Atlantic herring acoustic survey is a fisheries independent survey that provides scientific data for Atlantic herring assessments in the U.S. mid-Atlantic...

  3. NEFSC 2009 Atlantic Herring Acoustic/Midwater Trawl Survey (DE0910, EK500)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NEFSC Atlantic herring acoustic survey is a fisheries independent survey that provides scientific data for Atlantic herring assessments in the U.S. mid-Atlantic...

  4. NEFSC 2011 Atlantic Herring Acoustic/Midwater Trawl Survey (DE1108, EK60)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NEFSC Atlantic herring acoustic survey is a fisheries independent survey that provides scientific data for Atlantic herring assessments in the U.S. mid-Atlantic...

  5. NEFSC 2006 Atlantic Herring Acoustic/Midwater Trawl Survey (DE0615, EK500)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NEFSC Atlantic herring acoustic survey is a fisheries independent survey that provides scientific data for Atlantic herring assessments in the U.S. mid-Atlantic...

  6. NEFSC 2012 Atlantic Herring Acoustic/Midwater Trawl Survey (PC1206, EK60)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NEFSC Atlantic herring acoustic survey is a fisheries independent survey that provides scientific data for Atlantic herring assessments in the U.S. mid-Atlantic...

  7. NEFSC 2007 Atlantic Herring Acoustic/Midwater Trawl Survey (DE0710, EK500)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NEFSC Atlantic herring acoustic survey is a fisheries independent survey that provides scientific data for Atlantic herring assessments in the U.S. mid-Atlantic...

  8. NEFSC 2004 Atlantic Herring Acoustic/Midwater Trawl Survey (DE0413, EK500)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NEFSC Atlantic herring acoustic survey is a fisheries independent survey that provides scientific data for Atlantic herring assessments in the U.S. mid-Atlantic...

  9. NEFSC 1998 Atlantic Herring Acoustic/Midwater Trawl Survey (DE9810, EK500)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NEFSC Atlantic herring acoustic survey is a fisheries independent survey that provides scientific data for Atlantic herring assessments in the U.S. mid-Atlantic...

  10. NEFSC 2002 Atlantic Herring Acoustic/Midwater Trawl Survey (DE0208, EK500)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NEFSC Atlantic herring acoustic survey is a fisheries independent survey that provides scientific data for Atlantic herring assessments in the U.S. mid-Atlantic...

  11. Mid-Atlantic Regional Wind Energy Institute

    Energy Technology Data Exchange (ETDEWEB)

    Courtney Lane

    2011-12-20

    As the Department of Energy stated in its 20% Wind Energy by 2030 report, there will need to be enhanced outreach efforts on a national, state, regional, and local level to communicate wind development opportunities, benefits and challenges to a diverse set of stakeholders. To help address this need, PennFuture was awarded funding to create the Mid-Atlantic Regional Wind Energy Institute to provide general education and outreach on wind energy development across Maryland, Virginia, Delaware, Pennsylvania and West Virginia. Over the course of the two-year grant period, PennFuture used its expertise on wind energy policy and development in Pennsylvania and expanded it to other states in the Mid-Atlantic region. PennFuture accomplished this through reaching out and establishing connections with policy makers, local environmental groups, health and economic development organizations, and educational institutions and wind energy developers throughout the Mid-Atlantic region. PennFuture conducted two regional wind educational forums that brought together wind industry representatives and public interest organizations from across the region to discuss and address wind development in the Mid-Atlantic region. PennFuture developed the agenda and speakers in collaboration with experts on the ground in each state to help determine the critical issue to wind energy in each location. The sessions focused on topics ranging from the basics of wind development; model ordinance and tax issues; anti-wind arguments and counter points; wildlife issues and coalition building. In addition to in-person events, PennFuture held three webinars on (1) Generating Jobs with Wind Energy; (2) Reviving American Manufacturing with Wind Power; and (3) Wind and Transmission. PennFuture also created a web page for the institute (http://www.midatlanticwind.org) that contains an online database of fact sheets, research reports, sample advocacy letters, top anti-wind claims and information on how to

  12. CARINA oxygen data in the Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    I. Stendardo

    2009-12-01

    Full Text Available In the CARINA (Carbon dioxide in the Atlantic Ocean project, a new dataset with many previously unpublished hydrographic data from the Atlantic, Arctic and Southern Ocean was assembled and subjected to careful quality control (QC procedures. Here, we present the dissolved oxygen measurements in the Atlantic region of the dataset and describe in detail the secondary QC procedures that aim to ensure that the data are internally consistent. This is achieved by a cross-over analysis, i.e. the comparison of deep ocean data at places that were sampled by different cruises at different times. Initial adjustments to the individual cruises were then determined by an inverse procedure that computes a set of adjustments that requires the minimum amount of adjustment and at the same time reduces the offsets in an optimal manner. The initial adjustments were then reviewed by the CARINA members, and only those that passed the following two criteria were adopted: (i the region is not subject to substantial temporal variability, and (ii the adjustment must be based on at least three stations from each cruise. No adjustment was recommended for cruises that did not fit these criteria. The final CARINA-Oxygen dataset has 103414 oxygen samples from 9491 stations obtained during 98 cruises covering three decades. The sampling density of the oxygen data is particularly good in the North Atlantic north of about 40° N especially after 1987. In contrast, the sample density in the South Atlantic is much lower. Some cruises appear to have poor data quality, and were subsequently omitted from the adjusted dataset. Of the data included in the adjusted dataset, 20% were adjusted with a mean adjustment of 2%. Due to the achieved internal consistency, the resulting product is well suited to produce an improved climatology or to study long-term changes in the oxygen content of the ocean. However, the adjusted dataset is not necessarily better suited than the unadjusted data to

  13. The North Atlantic Oscillation: variability and interactions with the North Atlantic ocean and Artic sea ice

    Energy Technology Data Exchange (ETDEWEB)

    Jung, T.

    2000-07-01

    The North Atlantic oscillation (NAO) represents the dominant mode of atmospheric variability in the North Atlantic region and describes the strengthening and weakening of the midlatitude westerlies. In this study, variability of the NAO during wintertime and its relationship to the North Atlantic ocean and Arctic sea ice is investigated. For this purpose, observational data are analyzed along with integrations of models for the Atlantic ocean, Arctic sea ice, and the coupled global climate system. From a statistical point of view, the observed NAO index shows unusually high variance on interdecadal time scales during the 20th century. Variability on other time scales is consistent with realizations of random processes (''white noise''). Recurrence of wintertime NAO anomalies from winter-to-winter with missing signals during the inbetween nonwinter seasons is primarily associated with interdecadal variability of the NAO. This recurrence indicates that low-frequency changes of the NAO during the 20th century were in part externally forced. (orig.)

  14. 76 FR 2640 - Fisheries of the Northeastern United States; Atlantic Bluefish Fishery; 2011 Atlantic Bluefish...

    Science.gov (United States)

    2011-01-14

    ... status quo management measures for 2011, which would result in a TAL identical to the 2010 TAL, or 29.264... analyzed three alternatives (including a no action/status quo alternative) for the 2011 Atlantic bluefish... recreational sector. Alternative 3 (status quo) would allocate 10.051 million lb (4,559 mt) to the...

  15. 77 FR 72762 - Atlantic Surfclam and Ocean Quahog Fisheries; 2013 Fishing Quotas for Atlantic Surfclams and...

    Science.gov (United States)

    2012-12-06

    ... Atlantic surfclam and ocean quahog fisheries for 2013 will remain status quo. Regulations governing these... INFORMATION CONTACT: Jason Berthiaume, Fishery Management Specialist, (978) 281-9177; fax (978) 281-9135. SUPPLEMENTARY INFORMATION: Section 648.72(c) of the regulations implementing the fishery management plan...

  16. 75 FR 10450 - Fisheries of the Northeastern United States; Atlantic Bluefish Fisheries; 2010 Atlantic Bluefish...

    Science.gov (United States)

    2010-03-08

    ...). Alternative 3, the no action alternative, is considered to be synonymous with status quo management measures... a given phase in the rebuilding period, or the status quo F, whichever is less. According to... alternatives (including a no action/status quo alternative) for 2010 Atlantic bluefish fishery. All...

  17. 76 FR 65673 - Atlantic Highly Migratory Species; Atlantic Shark Management Measures; Correction

    Science.gov (United States)

    2011-10-24

    ... Register notice on October 7, 2011 (76 FR 62331). The notice also announced NMFS' intent to undertake... contains an error and is in need of correction. Correction Accordingly, in the October 7, 2011 (76 FR 62331... Species; Atlantic Shark Management Measures; Correction AGENCY: National Marine Fisheries Service...

  18. 76 FR 62331 - Atlantic Highly Migratory Species; Atlantic Shark Management Measures

    Science.gov (United States)

    2011-10-07

    ..., dusky, and blacknose sharks in the U.S. Atlantic and Gulf of Mexico were recently completed (76 FR 61092... (August 29, 2011, 76 FR 53652). Commercial regulations for blacknose sharks include, but are not limited... (May 4, 2010, 75 FR 23676). The Assessment Process was conducted via a series of webinars, during...

  19. 78 FR 54195 - Atlantic Highly Migratory Species; Atlantic Commercial Shark Fisheries

    Science.gov (United States)

    2013-09-03

    ... implemented and analyzed in the 2013 shark quota final rule (77 FR 75896, December 26, 2013) and in the final... Species; Atlantic Commercial Shark Fisheries AGENCY: National Marine Fisheries Service (NMFS), National.... SUMMARY: NMFS is transferring 68 metric tons (mt) dressed weight (dw) of non-blacknose small coastal...

  20. 77 FR 31562 - Atlantic Highly Migratory Species; Atlantic Shark Management Measures

    Science.gov (United States)

    2012-05-29

    ... October 7, 2011(76 FR 62331). This amendment is designed to rebuild and/or end overfishing on several... Species; Atlantic Shark Management Measures AGENCY: National Marine Fisheries Service (NMFS), National... considering the inclusion of Gulf of Mexico blacktip sharks in an amendment to the 2006 Consolidated...

  1. 78 FR 24148 - Atlantic Highly Migratory Species; Atlantic Shark Management Measures

    Science.gov (United States)

    2013-04-24

    ..., 2011 (76 FR 62331), we published an NOI that announced the stock status determinations for various... Magnuson-Stevens Act. On November 26, 2012, we published a proposed rule (77 FR 70552) for draft Amendment... Species; Atlantic Shark Management Measures AGENCY: National Marine Fisheries Service (NMFS),...

  2. 75 FR 57235 - Atlantic Highly Migratory Species; Atlantic Shark Management Measures

    Science.gov (United States)

    2010-09-20

    ... amendment is Amendment 3 to the 2006 Consolidated HMS FMP (75 FR 30484, June 1, 2010), which was based on... FR 250, January 5, 2010). Depending on the outcome of this ANPR process, NMFS will consider rules or... Species; Atlantic Shark Management Measures AGENCY: National Marine Fisheries Service (NMFS),...

  3. Some hydroids (Cnidaria: Hydrozoa) from the Mid-Atlantic Ridge, in the North Atlantic Ocean

    NARCIS (Netherlands)

    Calder, D.R.; Vervoort, W.

    1998-01-01

    An account is given of some hydroids from the Mid-Atlantic Ridge, collected during dives of submersibles "Nautile" (operated by IFREMER, France) and "Alvin" (operated by Woods Hole Oceanographic Institution, U.S.A). The specimens came from three main sectors of the ridge: 15 species from localities

  4. 75 FR 74004 - Atlantic Highly Migratory Species; Advisory Panel

    Science.gov (United States)

    2010-11-30

    ... data and models, used in stock assessments for oceanic sharks in the Atlantic Ocean, Gulf of Mexico... but not limited to data and models, used in stock assessments for oceanic sharks in the Atlantic Ocean... sharks, it may be expanded to include other HMS, as needed. The primary purpose of the individuals in...

  5. Geophysical and geodynamic studies of the North Atlantic Realm

    DEFF Research Database (Denmark)

    Schiffer, Christian

    2015-01-01

    The geology of the North Atlantic Realm (NAR), including the North Atlantic, Greenland, the Arctic, Iceland, Scandinavia, Northern Europe and Northeast America has been studied for more than a century and inspired some of the most fundamental theories in geoscience, such as plate tectonics...

  6. 78 FR 36753 - North Atlantic Coast Comprehensive Study

    Science.gov (United States)

    2013-06-19

    ... Department of the Army; Corps of Engineers North Atlantic Coast Comprehensive Study AGENCY: Department of the Army, U.S. Army Corps of Engineers, DoD. ACTION: Notice of Study Initiation. SUMMARY: The Congressional.... The goals of the North Atlantic Coast Comprehensive Study authorized under the Disaster...

  7. 76 FR 166 - Fresh and Chilled Atlantic Salmon From Norway

    Science.gov (United States)

    2011-01-03

    ... imports of fresh and chilled Atlantic salmon from Norway (56 FR 14920, 14921). Following five-year reviews... imports of fresh and chilled Atlantic salmon from Norway (71 FR 7512). The Commission is now conducting...), as most recently amended at 74 FR 2847 (January 16, 2009). \\1\\ \\1\\ No response to this request...

  8. Mid-Atlantic Wind - Overcoming the Challenges

    Energy Technology Data Exchange (ETDEWEB)

    Daniel F. Ancona III; Kathryn E. George; Lynn Sparling; Bruce C. Buckheit; Daniel LoBue; and Richard P. Bowers

    2012-06-29

    This study, supported by the US Department of Energy, Wind Powering America Program, Maryland Department of Natural Resources and Chesapeake Bay Foundation, analyzed barriers to wind energy development in the Mid-Atlantic region along with options for overcoming or mitigating them. The Mid-Atlantic States including Delaware, Maryland, North Carolina and Virginia, have excellent wind energy potential and growing demand for electricity, but only two utility-scale projects have been installed to date. Reasons for this apathetic development of wind resources were analyzed and quantified for four markets. Specific applications are: 1) Appalachian mountain ridgeline sites, 2) on coastal plains and peninsulas, 3) at shallow water sites in Delaware and Chesapeake Bays, Albemarle and Pamlico Sounds, and 4) at deeper water sites off the Atlantic coast. Each market has distinctly different opportunities and barriers. The primary barriers to wind development described in this report can be grouped into four categories; state policy and regulatory issues, wind resource technical uncertainty, economic viability, and public interest in environmental issues. The properties of these typologies are not mutually independent and do interact. The report concluded that there are no insurmountable barriers to land-based wind energy projects and they could be economically viable today. Likewise potential sites in sheltered shallow waters in regional bay and sounds have been largely overlooked but could be viable currently. Offshore ocean-based applications face higher costs and technical and wind resource uncertainties. The ongoing research and development program, revision of state incentive policies, additional wind measurement efforts, transmission system expansion, environmental baseline studies and outreach to private developers and stakeholders are needed to reduce barriers to wind energy development.

  9. Mid-Atlantic Wind - Overcoming the Challenges

    Energy Technology Data Exchange (ETDEWEB)

    Daniel F. Ancona III; Kathryn E. George; Richard P. Bowers; Dr. Lynn Sparling; Bruce Buckheit; Daniel LoBue

    2012-05-31

    This study, supported by the US Department of Energy, Wind Powering America Program, Maryland Department of Natural Resources and Chesapeake Bay Foundation, analyzed barriers to wind energy development in the Mid-Atlantic region along with options for overcoming or mitigating them. The Mid-Atlantic States including Delaware, Maryland, North Carolina and Virginia, have excellent wind energy potential and growing demand for electricity, but only two utility-scale projects have been installed to date. Reasons for this apathetic development of wind resources were analyzed and quantified for four markets. Specific applications are: 1) Appalachian mountain ridgeline sites, 2) on coastal plains and peninsulas, 3) at shallow water sites in Delaware and Chesapeake Bays, Albemarle and Pamlico Sounds, and 4) at deeper water sites off the Atlantic coast. Each market has distinctly different opportunities and barriers. The primary barriers to wind development described in this report can be grouped into four categories; state policy and regulatory issues, wind resource technical uncertainty, economic viability, and public interest in environmental issues. The properties of these typologies are not mutually independent and do interact. The report concluded that there are no insurmountable barriers to land-based wind energy projects and they could be economically viable today. Likewise potential sites in sheltered shallow waters in regional bay and sounds have been largely overlooked but could be viable currently. Offshore ocean-based applications face higher costs and technical and wind resource uncertainties. The ongoing research and development program, revision of state incentive policies, additional wind measurement efforts, transmission system expansion, environmental baseline studies and outreach to private developers and stakeholders are needed to reduce barriers to wind energy development.

  10. Origin and fate of the North Atlantic Current at the Mid-Atlantic Ridge

    Science.gov (United States)

    Breckenfelder, Tilia; Myers, Paul G.; Rhein, Monika; Pennelly, Clark; Hu, Xianmin

    2016-04-01

    Warm, salty tropical and subtropical water is brought into the subpolar gyre by the North Atlantic Current (NAC). The NAC is the northward extension of the Gulf Stream and is part of the upper branch of the Atlantic Meridional Overturning Circulation. The warm, salty water is further transported into the Nordic Seas via the Rockall Trough, into the Denmark Strait and, finally into the Labrador Sea, where it plays an important role in the deep water formation process. On its way into the Labrador Sea the water mass increases its density by dissipating heat to the atmosphere and thereby influencing the local climate. To further understand the processes behind warm water transport towards higher latitudes, we start our investigation at the Mid-Atlantic Ridge (MAR). Here, the NAC flows from the western to eastern basin of the North Atlantic and crosses the MAR via the Charlie-Gibbs, Faraday and Maxwell Fracture Zones. The role of the subpolar and subtropical gyre on the different water masses, and their properties, originating or reaching the MAR is studied using the lagrangian tool ARIANE with the 3D velocity fields taken from a 1/12° AGRIF nest set in a regional NEMO configuration. One result of this investigation is that the majority of particles released at the MAR, distributed over the entire water column, recirculate. Most of the remaining particles make their way into the East Greenland Current or turn in the eastern basin towards the south. The influence of the North Atlantic Oscillation (NAO) is investigated by studying the pathways of the NAC and their properties during different NAO phases.

  11. Seafloor Asymmetry in the Atlantic Ocean

    Institute of Scientific and Technical Information of China (English)

    S.S.Gao; K.H.Liu

    2004-01-01

    Measurements of seafloor asymmetry at about 360000 pairs of conjugate points along 1250 profiles across the mid-Atlantic Ridge(MAR)provide new constraints on models for the upwelling of the buoyant asthenosphere. The sign and amplitude of the asymmetry vary systematically and are functions of the distance between the spreading center and the location of the inferred location of maximum regional buoyancy(LMRB)in the asthenosphere. The LMRB is a smooth line derived from the observed asymmetry and is more centered at the regional topographic high than the spreading center. These observations are best explained by active upwelling of the underlying buoyant asthenosphere rather than by pressure-release melting.

  12. MACKINDER'S "HEARTLAND" THEORY AND THE ATLANTIC COMMUNITY

    OpenAIRE

    Sharapova, Sevara

    2005-01-01

    The term "Atlantic partnership" refers to the strong diplomatic and military links between the U.S. and major Western European countries such as Great Britain, Germany and France. The union established by these countries has been durable and reliable, especially during the Cold War. The European allies consistently supported the U.S. in military actions. However, in spite of dependence on the U.S., even during the Cold War the European states had many trade conflicts with the United States. N...

  13. North Atlantic Deep Water Production during the Last Glacial Maximum

    Science.gov (United States)

    Howe, Jacob N. W.; Piotrowski, Alexander M.; Noble, Taryn L.; Mulitza, Stefan; Chiessi, Cristiano M.; Bayon, Germain

    2016-06-01

    Changes in deep ocean ventilation are commonly invoked as the primary cause of lower glacial atmospheric CO2. The water mass structure of the glacial deep Atlantic Ocean and the mechanism by which it may have sequestered carbon remain elusive. Here we present neodymium isotope measurements from cores throughout the Atlantic that reveal glacial-interglacial changes in water mass distributions. These results demonstrate the sustained production of North Atlantic Deep Water under glacial conditions, indicating that southern-sourced waters were not as spatially extensive during the Last Glacial Maximum as previously believed. We demonstrate that the depleted glacial δ13C values in the deep Atlantic Ocean cannot be explained solely by water mass source changes. A greater amount of respired carbon, therefore, must have been stored in the abyssal Atlantic during the Last Glacial Maximum. We infer that this was achieved by a sluggish deep overturning cell, comprised of well-mixed northern- and southern-sourced waters.

  14. Tectonic provinces of the Atlantic Ocean

    Science.gov (United States)

    Pushcharovsky, Yu. M.

    2009-05-01

    The tectonic structure of the floor of the Atlantic Ocean beyond the continental margins is insufficiently studied. This is also true of its tectonic demarcation. The segmentation of the floor into regional-scale tectonic provinces of several orders proposed in this paper is primarily based on structural and historical geological features. It is shown that deep oceanic basins and fault tectonics are of particular importance in this respect. Tectonic provinces of two orders are distinguished by a set of attributes. The first-order provinces are the North, Central, South, and Antarctic domains of the Atlantic Ocean. They are separated by wide demarcation fracture zones into Transatlantic (transverse) second-order tectonic provinces. Ten such provinces are recognized (from the north southward): Greenland-Lofoten, Greenland-Scandinavia, Greenland-Ireland, Newfoundland-European, North American-African, Antilles-African, Angola-Brazil, Cape-Argentine, North Antarctic, and South Antarctic. This subdivision demonstrates significant differentiation in the geodynamic state of the oceanic lithosphere that determines nonuniform ocean formation and the tectonic features of the ocean floor. The latitudinal orientation of the second-order provinces inherits the past tectonic pattern, though newly formed structural units cannot be ruled out. The Earth rotation exerts a crucial effect on the crust and the mantle.

  15. Kinematics of the South Atlantic rift

    CERN Document Server

    Heine, Christian; Müller, R Dietmar

    2013-01-01

    The South Atlantic rift basin evolved as branch of a large Jurassic-Cretaceous intraplate rift zone between the African and South American plates during the final breakup of western Gondwana. By quantitatively accounting for crustal deformation in the Central and West African rift zone, we indirectly construct the kinematic history of the pre-breakup evolution of the conjugate West African-Brazilian margins. Our model suggests a causal link between changes in extension direction and velocity during continental extension and the generation of marginal structures such as the enigmatic Pre-salt sag basin and the S\\~ao Paulo High. We model an initial E-W directed extension between South America and Africa (fixed in present-day position) at very low extensional velocities until Upper Hauterivian times ($\\approx$126 Ma) when rift activity along in the equatorial Atlantic domain started to increase significantly. During this initial $\\approx$17 Myr-long stretching episode the Pre-salt basin width on the conjugate Br...

  16. The enigmatic whale: the North Atlantic humpback

    Directory of Open Access Journals (Sweden)

    Tim D Smith

    2013-10-01

    Full Text Available We know more about the North Atlantic humpback whale (Megaptera novaeangliae than we do for virtually any other cetacean, yet attempts to use this information to describe the status of the populations in this ocean basin have not proven satisfactory. The North Atlantic humpback has been the subject of extensive research over the past few decades, resulting in a substantial amount of knowledge about what has proven to be a species with a very complex life history and population structure. While several population models have been developed to integrate the available information, the data overall are not well described by any of the models. This has left considerable uncertainty about population status, and has raised questions about the interpretation of some of the data. We describe 7 specific areas where puzzling or ambiguous observations have been made; these require closer attention if population status is to be determined. These areas raise several fundamental questions, including: How many breeding populations are there? How much do the populations mix on the feeding grounds? How has the distribution of animals on both feeding and breeding grounds changed? We identify additional research needed to address the 7 areas and these questions in particular, so that population status might be determined.

  17. 50 CFR 622.18 - South Atlantic snapper-grouper limited access.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false South Atlantic snapper-grouper limited... ATLANTIC Effort Limitations § 622.18 South Atlantic snapper-grouper limited access. (a) General. The only valid commercial vessel permits for South Atlantic snapper-grouper are those that have been issued...

  18. Analysing migrations of Atlantic cod Gadus morhua in the north‐east Atlantic Ocean

    DEFF Research Database (Denmark)

    Neuenfeldt, S.; Righton, D.; Neat, F.;

    2013-01-01

    descriptions, separation of reproductively isolated populations, timing and areas of spawning, tidal transport and use of protected areas. The examples are based on archival tag data from the North Sea, the Baltic Sea, the Barents Sea and Faroese and Icelandic Waters. Besides presenting the state......-of-the-art geolocations for cod Gadus morhua in the north-east Atlantic Ocean, the major aim of this review is to raise awareness of gaps in knowledge and to identify ideas for new research...

  19. South Atlantic island record reveals a South Atlantic response to the 8.2 kyr event

    OpenAIRE

    Ljung, K.; Björck, S.; Renssen, H.; D. Hammarlund

    2007-01-01

    International audience One of the most distinct climate fluctuations during the Holocene is the short and rapid event centred around 8200 years ago, the 8.2 kyr event, which was most likely triggered by glacial melt-water forcing from the receding Laurentide ice-sheet. Evidence for this cooling has primarily been reported from sites around the North Atlantic, but an increasing number of observations imply a more wide-spread occurrence. Palaeoclimate archives from the Southern Hemisphere ha...

  20. Estimation of Atlantic-Mediterranean netflow variability

    Science.gov (United States)

    Guerreiro, Catarina; Peliz, Alvaro; Miranda, Pedro

    2016-04-01

    The exchanges at the Strait of Gibraltar are extremely difficult to measure due to the strong temporal and across-strait variabilities; yet the Atlantic inflow into the Mediterranean is extremely important both for climate and to ecosystems. Most of the published numerical modeling studies do not resolve the Strait of Gibraltar realistically. Models that represent the strait at high resolution focus primarily in high frequency dynamics, whereas long-term dynamics are studied in low resolution model studies, and for that reason the Strait dynamics are poorly resolved. Estimating the variability of the exchanges requires long term and high-resolutions studies, thus an improved simulation with explicit and realistic representation of the Strait is necessary. On seasonal to inter-annual timescales the flow is essentially driven by the net evaporation contribution and consequently realistic fields of precipitation and evaporation are necessary for model setup. A comparison between observations, reanalysis and combined products shows ERA-Interim Reanalysis has the most suitable product for Mediterranean Sea. Its time and space variability are in close agreement with NOC 1.1 for the common period (1980 - 1993) and also with evaporation from OAFLUX (1989 - 2014). Subinertial fluctuations, periods from days to a few months, are the second most energetic, after tides, and are the response to atmospheric pressure fluctuations and local winds. Atmospheric pressure fluctuations in the Mediterranean cause sea level oscillations that induce a barotropic flow through the Strait. Candela's analytical model has been used to quantify this response in later studies, though comparison with observations points to an underestimation of the flow at strait. An improved representation of this term contribution to the Atlantic - Mediterranean exchange must be achieved on longer time-scales. We propose a new simulation for the last 36 years (1979 - 2014) for the Mediterranean - Atlantic

  1. AMO-like variations of holocene sea surface temperatures in the North Atlantic Ocean

    OpenAIRE

    Feng, S; Hu, Q; Oglesby, R. J.

    2009-01-01

    Instrumental records of the North Atlantic sea surface temperatures (SST) show a significant 60–80 year cycle, referred to as the Atlantic Multidecadal Oscillation (AMO). During AMO warm (cold) phases, SST over the entire North Atlantic Ocean is dominated by basin-wide positive (negative) anomalies. We analyzed SST variations in the North Atlantic Ocean for the last 10 ka. The long-term and centennial variations of Holocene SST in the North Atlantic demonstrate a basin-wide mode that clearly ...

  2. An electrical analogy relating the Atlantic multidecadal oscillation to the Atlantic meridional overturning circulation.

    Directory of Open Access Journals (Sweden)

    Bruce E Kurtz

    Full Text Available The Atlantic meridional overturning circulation (AMOC is the northward flow of surface water to subpolar latitudes where deepwater is formed, balanced by southward abyssal flow and upwelling in the vicinity of the Southern Ocean. It is generally accepted that AMOC flow oscillates with a period of 60-80 years, creating a regular variation in North Atlantic sea surface temperature known as the Atlantic multidecadal oscillation (AMO. This article attempts to answer two questions: how is the AMOC driven and why does it oscillate? Using methods commonly employed by chemical engineers for analyzing processes involving flowing liquids, apparently not previously applied to trying to understand the AMOC, an equation is developed for AMOC flow as a function of the meridional density gradient or the corresponding temperature gradient. The equation is based on the similarity between the AMOC and an industrial thermosyphon loop cooler, which circulates a heat transfer liquid without using a mechanical pump. Extending this equation with an analogy between the flow of heat and electricity explains why the AMOC flow oscillates and what determines its period. Calculated values for AMOC flow and AMO oscillation period are in good agreement with measured values.

  3. South Atlantic island record reveals a South Atlantic response to the 8.2 kyr event

    Directory of Open Access Journals (Sweden)

    K. Ljung

    2007-05-01

    Full Text Available One of the most distinct climate fluctuations during the Holocene is the short and rapid event centred around 8200 years ago, the 8.2 kyr event, which was most likely triggered by glacial melt-water forcing from the receding Laurentide ice-sheet. Evidence for this cooling has primarily been reported from sites around the North Atlantic, but an increasing number of observations imply a more wide-spread occurrence. Palaeoclimate archives from the Southern Hemisphere have hitherto failed to uncover a distinct climatic anomaly associated with the 8.2 kyr event. Here we present a lake sediment record from Nightingale Island in the central South Atlantic showing enhanced precipitation between 8275 and 8025 cal. yrs BP, most likely as a consequence of increased sea surface temperature (SST. We show that this is consistent with climate model projections of a warming of the South Atlantic in response to reduced north-ward energy transport during the 8.2 kyr event.

  4. South Atlantic island record reveals a South Atlantic response to the 8.2 kyr event

    Directory of Open Access Journals (Sweden)

    K. Ljung

    2008-02-01

    Full Text Available One of the most distinct climate fluctuations during the Holocene is the short and rapid event centred around 8200 years ago, the 8.2 kyr event, which was most likely triggered by glacial melt-water forcing from the receding Laurentide ice-sheet. Evidence for this cooling has primarily been reported from sites around the North Atlantic, but an increasing number of observations imply a more wide-spread occurrence. Palaeoclimate archives from the Southern Hemisphere have hitherto failed to uncover a distinct climatic anomaly associated with the 8.2 kyr event. Here we present a lake sediment record from Nightingale Island in the central South Atlantic showing enhanced precipitation between 8275 and 8025 cal. yrs BP, most likely as a consequence of increased sea surface temperature (SST. We show that this is consistent with climate model projections of a warming of the South Atlantic in response to reduced north-ward energy transport during the 8.2 kyr event.

  5. Atmospheric transmission of North Atlantic Heinrich events

    Science.gov (United States)

    Hostetler, S.W.; Clark, P.U.; Bartlein, P.J.; Mix, A.C.; Pisias, N.J.

    1999-01-01

    We model the response of the climate system during Heinrich event 2 (H2) by employing an atmospheric general circulation model, using boundary conditions based on the concept of a "canonical" Heinrich event. The canonical event is initialized with a full-height Laurentide ice sheet (LIS) and CLIMAP sea surface temperatures (SSTs), followed by lowering of the LIS, then warming of North Atlantic SSTs. Our modeled temperature and wind fields exhibit spatially variable responses over the Northern Hemisphere at each stage of the H2 event. In some regions the climatic responses are additive, whereas in other regions they cancel or are of opposite sign, suggesting that Heinrich event climatic variations may have left complex signatures in geologic records. We find variations in the tropical water balance and the mass balance of ice sheets, and implications for variations in terrestrial methane production from the contraction of northern permafrost regions and the expansion of tropical wetlands. Copyright 1999 by the American Geophysical Union.

  6. Atlantic hurricane surge response to geoengineering.

    Science.gov (United States)

    Moore, John C; Grinsted, Aslak; Guo, Xiaoran; Yu, Xiaoyong; Jevrejeva, Svetlana; Rinke, Annette; Cui, Xuefeng; Kravitz, Ben; Lenton, Andrew; Watanabe, Shingo; Ji, Duoying

    2015-11-10

    Devastating floods due to Atlantic hurricanes are relatively rare events. However, the frequency of the most intense storms is likely to increase with rises in sea surface temperatures. Geoengineering by stratospheric sulfate aerosol injection cools the tropics relative to the polar regions, including the hurricane Main Development Region in the Atlantic, suggesting that geoengineering may mitigate hurricanes. We examine this hypothesis using eight earth system model simulations of climate under the Geoengineering Model Intercomparison Project (GeoMIP) G3 and G4 schemes that use stratospheric aerosols to reduce the radiative forcing under the Representative Concentration Pathway (RCP) 4.5 scenario. Global mean temperature increases are greatly ameliorated by geoengineering, and tropical temperature increases are at most half of those temperature increases in the RCP4.5. However, sulfate injection would have to double (to nearly 10 teragrams of SO2 per year) between 2020 and 2070 to balance the RCP4.5, approximately the equivalent of a 1991 Pinatubo eruption every 2 y, with consequent implications for stratospheric ozone. We project changes in storm frequencies using a temperature-dependent generalized extreme value statistical model calibrated by historical storm surges and observed temperatures since 1923. The number of storm surge events as big as the one caused by the 2005 Katrina hurricane are reduced by about 50% compared with no geoengineering, but this reduction is only marginally statistically significant. Nevertheless, when sea level rise differences in 2070 between the RCP4.5 and geoengineering are factored into coastal flood risk, we find that expected flood levels are reduced by about 40 cm for 5-y events and about halved for 50-y surges.

  7. Atlantic hurricane surge response to geoengineering

    Energy Technology Data Exchange (ETDEWEB)

    Moore, John C.; Grinsted, Aslak; Guo, Xiaoran; Yu, Xiaoyong; Jevrejeva, Svetlana; Rinke, Annette; Cui, Xuefeng; Kravitz, Ben; Lenton, Andrew; Watanabe, Shingo; Ji, Duoying

    2015-10-26

    Devastating Atlantic hurricanes are relatively rare events. However their intensity and frequency in a warming world may rapidly increase by a factor of 2-7 for each degree of increase in mean global temperature. Geoengineering by stratospheric sulphate aerosol injection cools the tropics relative to the polar regions, including the hurricane main development region in the Atlantic, suggesting that geoengineering may be an effective method of controlling hurricanes. We examine this hypothesis using 8 Earth System Model simulations of climate under the GeoMIP G3 and G4 schemes that use stratospheric aerosols to reduce the radiative forcing under the RCP4.5 scenario. Global mean temperature increases are greatly ameliorated by geoengineering, and tropical temperature increases are at most half of those in RCP4.5, but sulphate injection would have to double between 2020 and 2070 to balance RCP 4.5 to nearly 10 Tg SO2 yr-1, with consequent implications for damage to stratospheric ozone. We project changes in storm frequencies using a temperature-dependent Generalized Extreme Value statistical model calibrated by historical storm surges from 1923 and observed temperatures. The numbers of storm surge events as big as the one that caused the 2005 Katrina hurricane are reduced by about 50% compared with no geoengineering, but this is only marginally statistically significant. However, when sea level rise differences at 2070 between RCP4.5 and geoengineering are factored in to coastal flood risk, we find that expected flood levels are reduced by about 40 cm for 5 year events and perhaps halved for 50 year surges.

  8. Atlantic hurricane surge response to geoengineering.

    Science.gov (United States)

    Moore, John C; Grinsted, Aslak; Guo, Xiaoran; Yu, Xiaoyong; Jevrejeva, Svetlana; Rinke, Annette; Cui, Xuefeng; Kravitz, Ben; Lenton, Andrew; Watanabe, Shingo; Ji, Duoying

    2015-11-10

    Devastating floods due to Atlantic hurricanes are relatively rare events. However, the frequency of the most intense storms is likely to increase with rises in sea surface temperatures. Geoengineering by stratospheric sulfate aerosol injection cools the tropics relative to the polar regions, including the hurricane Main Development Region in the Atlantic, suggesting that geoengineering may mitigate hurricanes. We examine this hypothesis using eight earth system model simulations of climate under the Geoengineering Model Intercomparison Project (GeoMIP) G3 and G4 schemes that use stratospheric aerosols to reduce the radiative forcing under the Representative Concentration Pathway (RCP) 4.5 scenario. Global mean temperature increases are greatly ameliorated by geoengineering, and tropical temperature increases are at most half of those temperature increases in the RCP4.5. However, sulfate injection would have to double (to nearly 10 teragrams of SO2 per year) between 2020 and 2070 to balance the RCP4.5, approximately the equivalent of a 1991 Pinatubo eruption every 2 y, with consequent implications for stratospheric ozone. We project changes in storm frequencies using a temperature-dependent generalized extreme value statistical model calibrated by historical storm surges and observed temperatures since 1923. The number of storm surge events as big as the one caused by the 2005 Katrina hurricane are reduced by about 50% compared with no geoengineering, but this reduction is only marginally statistically significant. Nevertheless, when sea level rise differences in 2070 between the RCP4.5 and geoengineering are factored into coastal flood risk, we find that expected flood levels are reduced by about 40 cm for 5-y events and about halved for 50-y surges. PMID:26504210

  9. The impact of North Atlantic sea surface temperature errors on the simulation of North Atlantic European region climate

    OpenAIRE

    Keeley, Sarah; Sutton, Rowan; Shaffrey, Len

    2012-01-01

    Current state-of-the-art climate models fail to capture accurately the path of the Gulf Stream and North Atlantic Current. This leads to a warm bias near the North American coast, where the modelled Gulf Stream separates from the coast further north, and a cold anomaly to the east of the Grand Banks of Newfoundland, where the North Atlantic Current remains too zonal in this region. Using an atmosphere-only model forced with the sea surface temperature (SST) biases in the North Atlantic, we...

  10. Decadal predictions of the North Atlantic CO2 uptake.

    Science.gov (United States)

    Li, Hongmei; Ilyina, Tatiana; Müller, Wolfgang A; Sienz, Frank

    2016-01-01

    As a major CO2 sink, the North Atlantic, especially its subpolar gyre region, is essential for the global carbon cycle. Decadal fluctuations of CO2 uptake in the North Atlantic subpolar gyre region are associated with the evolution of the North Atlantic Oscillation, the Atlantic meridional overturning circulation, ocean mixing and sea surface temperature anomalies. While variations in the physical state of the ocean can be predicted several years in advance by initialization of Earth system models, predictability of CO2 uptake has remained unexplored. Here we investigate the predictability of CO2 uptake variations by initialization of the MPI-ESM decadal prediction system. We find large multi-year variability in oceanic CO2 uptake and demonstrate that its potential predictive skill in the western subpolar gyre region is up to 4-7 years. The predictive skill is mainly maintained in winter and is attributed to the improved physical state of the ocean. PMID:27026490

  11. Science and Society: The Third Dimension of the Atlantic Alliance.

    Science.gov (United States)

    Sudarskis, Michel

    1983-01-01

    Discusses North Atlantic Treaty Organization (NATO) activities related to science and society. NATO Scientific Exchanges Programme; pilot studies (pollution control, natural resources, health and technological risks, quality of life, and planning); and cultural exchanges are among the areas considered. (JN)

  12. Inventory of Atlantic White Cedar Remnant Stands in North Carolina.

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This inventory was commissioned by the U.S. Air Force to identify the location and condition of extant remnant Atlantic white cedar groves and stands in North...

  13. Climate Prediction Center (CPC) East Atlantic Teleconnection Pattern Index

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Monthly tabulated index of the East Atlantic Teleconnection pattern. The data spans the period 1950 to present. The index is derived from a rotated principal...

  14. Research Ship Atlantic Explorer Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship Atlantic Explorer Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and...

  15. Subcropping Geology for the Mid-Atlantic Coastal Plain

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Subcropping geology for the Mid-Atlantic Coastal Plain was compiled and interpreted from available published sources. Formation contacts were interpolated across...

  16. Outer Continental Shelf Lease Blocks - Atlantic Region NAD83

    Data.gov (United States)

    Bureau of Ocean Energy Management, Department of the Interior — This data set contains OCS block outlines in ArcGIS shape file format for the BOEM Atlantic Region. OCS blocks are used to define small geographic areas within an...

  17. Outer Continental Shelf Official Protraction Diagrams - Atlantic Region NAD 83

    Data.gov (United States)

    Bureau of Ocean Energy Management, Department of the Interior — This data set contains Official Protraction Diagram (OPD) outlines in ESRI shapefile format. Atlantic Region OPDs are approximately 2 degrees wide by one degree...

  18. Physiography for the Mid-Atlantic Coastal Plain

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Physiography for the Mid-Atlantic Coastal Plain was constructed by standardizing and extrapolating previous physiographic interpretations for areas within and...

  19. Economic Assessment of the Atlantic Coast Horseshoe Crab Fishery

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In this report, Industrial Economics, Incorporated (lEc) provides an assessment of the economic value of the Atlantic Coast horseshoe crab fishery. We accomplish...

  20. Atlantic Sharpnose and Blacknose Shark Congressional Supplemental Sampling

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Life history data were collected from Atlantic sharpnose and blacknose sharks during the Congressional Supplemental Program during 2011. Data collected include...

  1. A Low-Li Geochemical Province in the NE Atlantic

    DEFF Research Database (Denmark)

    Bailey, J. C.; Gwozdz, R.

    1978-01-01

    , over 20° of latitude and regardless of basalt type and chemistry. This low-Li province and the increasing Li contents of ocean-ridge tholeiites into the S Atlantic are believed to monitor Li heterogeneity in the underlying mantle. Li, like Na, increases gently during the differentiation of several......Lithium was analysed in 392 basalts and related igneous rocks from the North Atlantic Tertiary-Recent province using activation analysis and Čerenkov counting. Monotonous Li values of 5.5±2 ppm in NE Atlantic basalts define a low-Li geochemical province which has persisted for 60 million years...... basalt series. No whole-rock coherence is observed between Li and Mg, K, Rb or Ca. Mantle phlogopite is considered to play an insignificant rôle in controlling the Li levels of NE Atlantic basalts....

  2. South Atlantic Seasonal and/or Area Closures GIS data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the geographic area described in Title 50 CFR Part 622 Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic, Subpart A - General...

  3. Transport of salt and freshwater in the Atlantic Subpolar Gyre

    Science.gov (United States)

    Born, Andreas; Stocker, Thomas F.; Sandø, Anne Britt

    2016-09-01

    Transport of salt in the Irminger Current, the northern branch of the Atlantic Subpolar Gyre coupling the eastern and western subpolar North Atlantic, plays an important role for climate variability across a wide range of time scales. High-resolution ocean modeling and observations indicate that salinities in the eastern subpolar North Atlantic decrease with enhanced circulation of the North Atlantic subpolar gyre (SPG). This has led to the perception that a stronger SPG also transports less salt westward. In this study, we analyze a regional ocean model and a comprehensive global coupled climate model, and show that a stronger SPG transports more salt in the Irminger Current irrespective of lower salinities in its source region. The additional salt converges in the Labrador Sea and the Irminger Basin by eddy transports, increases surface salinity in the western SPG, and favors more intense deep convection. This is part of a positive feedback mechanism with potentially large implications for climate variability and predictability.

  4. Atlantic Warm Pool Trigger for the Younger Dryas Climate Event

    Science.gov (United States)

    Abdul, N. A.; Mortlock, R. A.; Wright, J. D.; Fairbanks, R. G.; Teneva, L. T.

    2011-12-01

    There is growing evidence that variability in the size and heat content of the tropical Atlantic Warm Pool impacts circum-North Atlantic climate via the Atlantic Multi-decadal Oscillation mode (Wang et al., 2008). The Atlantic Warm Pool spans the Gulf of Mexico, Caribbean Sea and the western tropical North Atlantic. Barbados is located near the center of the tropical Atlantic Warm Pool and coupled ocean models suggest that Barbados remains near the center of the tropical Atlantic Warm Pool under varying wind stress simulations. Measurements of the oxygen isotope paleothermometer in Acropora palmata coral species recovered from cores offshore Barbados, show a 3oC monotonic decrease in sea surface temperature from 13106 ± 83 to 12744 ± 61 years before present (errors given as 2 sigma). This interval corresponds to a sea level rise from 71.4 meters to 67.1 meters below present levels at Barbados. The 3oC temperature decrease is captured in eight A. palmata specimens that are in stratigraphic sequence, 230Th/234U dated, and analyzed for oxygen isotopes. All measurements are replicated. We are confident that this is the warm pool equivalent of the Younger Dryas climate event. The initiation of this temperature drop in the Atlantic Warm Pool predates the Younger Dryas start in Greenland ice cores, reported to start at 12896 ± 138 years (relative to AD 2000) (Rasmussen et al., 2006), while few other Younger Dryas climate records are dated with similar accuracy to make the comparison. Rasmussen, S.O., Andersen, K.K., Svensson, A.M., Steffensen, J.P., Vinther, B.M., Clausen, H.B., Siggaard-Andersen, M.L., Johnsen, S.J., Larsen, L.B., Dahl-Jensen, D., Bigler, M., Röthlisberger, R., Fischer, H., Goto-Azuma, K., Hansson, M.E., and Ruth, U., 2006, A new Greenland ice core chronology for the last glacial termination: J. Geophys. Res., v. 111, p. D06102. Wang, C., Lee, S.-K., and Enfield, D.B., 2008, Atlantic Warm Pool acting as a link between Atlantic Multidecadal

  5. Projected Atlantic hurricane surge threat from rising temperatures

    OpenAIRE

    Grinsted, Aslak; Moore, John C.; Jevrejeva, Svetlana

    2013-01-01

    Detection and attribution of past changes in cyclone activity are hampered by biased cyclone records due to changes in observational capabilities. Here, we relate a homogeneous record of Atlantic tropical cyclone activity based on storm surge statistics from tide gauges to changes in global temperature patterns. We examine 10 competing hypotheses using nonstationary generalized extreme value analysis with different predictors (North Atlantic Oscillation, Southern Oscillation, Pacific Decadal ...

  6. Operational numerical prediction of rapid cyclogenesis over the North Atlantic

    OpenAIRE

    GADD, A. J.; HALL, C. D.; KRUZE, R. E.

    2011-01-01

    The current generation of operational numerical weather prediction models has shown considerable skill in handling cyclogenesis. This paper assesses the accuracy of forecasts of rapid cyclogenesis over the North Atlantic from the operational NWP system at Bracknell and attempts to isolate the factors relevant to successful prediction. Illustrative material is drawn in particular from the case of the record low pressure centre that developed over the North Atlantic on 14 December 1986.DOI: 10....

  7. Population genetic studies in Northeastern Atlantic minke whales

    OpenAIRE

    Berube, M.; Skaug, Hans Julius; Andersen, Liselotte W.; Haug, Tore; Øien, Nils

    2007-01-01

    Minke whales are the most abundance species of baleen whales in the North Atlantic. As part of current management of minke whales in Norwegian and adjacent waters, a DNA-register have been established. The register ensures that samples are taken of each animal caught under the Norwegian catch quota, and that a DNA-profile is established and stored in a database from each individual whale. Previous studies have indicated that genetic population sub-structure exists within the North Atlantic, b...

  8. On multidecadal and quasi-decadal North Atlantic variability

    OpenAIRE

    Alvarez-Garcia, F.; Latif, Mojib; Biastoch, Arne

    2008-01-01

    Observed sea surface temperatures (SSTs) in the North Atlantic from 1958 through 2000, as well as data from an ocean model simulation driven with the atmospheric variability observed during the same period, are examined using multichannel singular spectrum analysis. The two leading oscillatory modes are associated with a multidecadal and a quasi-decadal period. The former is connected to a basinwide uniform SST pattern and changes in the deep North Atlantic meridional overturning circulation....

  9. Tropical versus high latitude freshwater influence on the Atlantic circulation

    OpenAIRE

    Goelzer, H.; J. Mignot; Levermann, A; Rahmstorf, S.

    2006-01-01

    We investigate the model sensitivity of the Atlantic meridional overturning circulation (AMOC) to anomalous freshwater flux in the tropical and northern Atlantic. Forcing in both locations leads to the same qualitative response: a positive freshwater anomaly induces a weakening of the AMOC and a negative freshwater anomaly strengthens the AMOC. Strong differences arise in the temporal characteristics and amplitude of the response. The advection of the tropical anomaly up to the deep water for...

  10. Many Seasons Gone: Memory, History, and the Atlantic Slave Trade

    OpenAIRE

    Ted Maris-Wolf

    2009-01-01

    [First paragraph] African Voices of the Atlantic Slave Trade: Beyond the Silence and the Shame. Anne C. Bailey. Boston: Beacon Press, 2005. 289 pp. (Cloth US $ 26.00) Lose Your Mother: A Journey along the Atlantic Slave Route. Saidiya Hartman. New York: Farrar, Straus and Giroux, 2007. xi + 270 pp. (Cloth US $ 25.00) In Two Thousand Seasons, the great Ghanaian novelist Ayi Kwei Armah describes the effects of centuries of European exploitation and violence in Africa and th...

  11. Potential tropical Atlantic impacts on Pacific decadal climate trends

    Science.gov (United States)

    Chikamoto, Y.; Mochizuki, T.; Timmermann, A.; Kimoto, M.; Watanabe, M.

    2016-07-01

    The tropical Pacific cooling from the early 1990s to 2013 has contributed to the slowdown of globally averaged sea surface temperatures (SSTs). The origin of this regional cooling trend still remains elusive. Here we demonstrate that the remote impact of Atlantic SST anomalies, as well as local atmosphere-ocean interactions, contributed to the eastern Pacific cooling during this period. By assimilating observed three-dimensional Atlantic temperature and salinity anomalies into a coupled general circulation model, we are able to qualitatively reproduce the observed Pacific decadal trends of SST and sea level pressure (SLP), albeit with reduced amplitude. Although a major part of the Pacific SLP trend can be explained by equatorial Pacific SST forcing only, the origin of this low-frequency variability can be traced back further to the remote impacts of equatorial Atlantic and South Atlantic SST trends. Atlantic SST impacts on the atmospheric circulation can also be detected for the Northeastern Pacific, thus providing a linkage between Atlantic climate and Western North American drought conditions.

  12. Reorganization of the North Atlantic Oscillation during early Holocene deglaciation

    Science.gov (United States)

    Wassenburg, Jasper A.; Dietrich, Stephan; Fietzke, Jan; Fohlmeister, Jens; Jochum, Klaus Peter; Scholz, Denis; Richter, Detlev K.; Sabaoui, Abdellah; Spötl, Christoph; Lohmann, Gerrit; Andreae, Meinrat O.; Immenhauser, Adrian

    2016-08-01

    The North Atlantic Oscillation is the dominant atmospheric pressure mode in the North Atlantic region and affects winter temperature and precipitation in the Mediterranean, northwest Europe, Greenland, and Asia. The index that describes the sea-level pressure difference between Iceland and the Azores is correlated with a dipole precipitation pattern over northwest Europe and northwest Africa. How the North Atlantic Oscillation will develop as the Greenland ice sheet melts is unclear. A potential past analogue is the early Holocene, during which melting ice sheets around the North Atlantic freshened surface waters, affecting the strength of the meridional overturning circulation. Here we present a Holocene rainfall record from northwest Africa based on speleothem δ18O and compare it against a speleothem-based rainfall record from Europe. The two records are positively correlated during the early Holocene, followed by a shift to an anti-correlation, similar to the modern record, during the mid-Holocene. On the basis of our simulations with an Earth system model, we suggest the shift to the anti-correlation reflects a large-scale atmospheric and oceanic reorganization in response to the demise of the Laurentide ice sheet and a strong reduction of meltwater flux to the North Atlantic, pointing to a potential sensitivity of the North Atlantic Oscillation to the melting of ice sheets.

  13. South Atlantic Bight Habitat Mapping on NOAA Ship Nancy Foster in North Atlantic Ocean between 20070626 and 20070702

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This expedition on the NOAA Ship Nancy Foster used the recently-developed National Undersea Research Center for the North Atlantic and Great Lakes (NURC-NAGL) ROV...

  14. Ionoregulatory Aspects of the Osmorespiratory Compromise during Acute Environmental Hypoxia in 12 Tropical and Temperate Teleosts.

    Science.gov (United States)

    Robertson, Lisa M; Val, Adalberto Luis; Almeida-Val, Vera F; Wood, Chris M

    2015-01-01

    In the traditional osmorespiratory compromise, as seen in the hypoxia-intolerant freshwater rainbow trout (Oncorhynchus mykiss), the branchial modifications that occur to improve O2 uptake during hypoxia result in unfavorable increases in the fluxes of ions and water. However, at least one hypoxia-tolerant freshwater species, the Amazonian oscar (Astronotus ocellatus), shows exactly the opposite: decreased branchial flux rates of ions, water, and nitrogenous wastes during acute hypoxia. In order to find out whether the two strategies were widespread, we used a standard 2-h normoxia, 2-h hypoxia (20%-30% saturation), 2-h normoxic recovery protocol to survey 10 other phylogenetically diverse tropical and temperate species. Unidirectional influx and efflux rates of Na(+) and net flux rates of K(+), ammonia, and urea-N were measured. The flux reduction strategy was seen only in one additional species, the Amazonian tambaqui (Colossoma macropomum), which is similarly hypoxia tolerant and lives in the same ion-poor waters as the oscar. However, five other species exhibited evidence of the increased flux rates typical of the traditional osmorespiratory compromise in the trout: the rosaceu tetra (Hyphessobrycon bentosi rosaceus), the moenkhausia tetra (Moenkhausia diktyota), the bluegill sunfish (Lepomis macrochirus), the zebra fish (Danio rerio), and the goldfish (Carassius auratus). Four other species exhibited no marked flux changes during hypoxia: the cardinal tetra (Paracheirodon axelrodi), the hemigrammus tetra (Hemigrammus rhodostomus), the pumpkinseed sunfish (Lepomis gibbosus), and the Atlantic killifish (Fundulus heteroclitus). Overall, a diversity of strategies exist; we speculate that these may be linked to differences in habitat and/or lifestyle. PMID:26052633

  15. Rainfall distribution in the Atlantic Rainforest

    Directory of Open Access Journals (Sweden)

    João Paulo Oliveira de Freitas

    2013-08-01

    Full Text Available Forest cover is of great importance in the context of water balance and may alter the mechanism of water absorption into the soil surface. The aim of this study was to evaluate the throughfall, stemflow, and surface runoff compared to rainfall in a fragment of the Atlantic Rainforest. Rainfall was measured through a rain gauge and a pluviograph installed on a tower above the forest canopy. To quantify the throughfall, six plots of 20 x20 m were laid, with 25 pluviometers five meters spaced from each other, for each plot. To measure the stemflow, collectors were adapted on the tree trunks having ≥ 15 cm circumference. For the runoff estimate, three plots were established with areas of 13.71 m², 14.79 m² and 14.86 m². The plots were demarcated with galvanized iron sheets. Based on the results, it can be concluded that forests play an important role in the hydrological cycle: from the total precipitation (1182.6 mm, one portion is intercepted by the tree canopy and evaporated back into the atmosphere; another portion (958.1 mm corresponding to 81% of the total precipitation, passes through the canopy and hits the ground. The stemflow was 10.8 mm, corresponding to 0.9 % of the total rainfall. The runoff was 15.5 mm, which corresponds to 1.3% of the rainfall. The vegetation has an important role in reducing the runoff volume on the soil surface.

  16. Moisture transport from the Atlantic to the Pacific basin and its response to North Atlantic cooling and global warming

    Energy Technology Data Exchange (ETDEWEB)

    Richter, Ingo [University of Hawaii at Manoa, International Pacific Research Center, Honolulu, HI (United States); Xie, Shang-Ping [University of Hawaii at Manoa, Department of Meteorology, Honolulu, HI (United States)

    2010-08-15

    Atmospheric moisture transport from the Atlantic to the Pacific basin plays an important role in regulating North Atlantic salinity and thus the strength of the thermohaline circulation. Potential changes in the strength of this moisture transport are investigated for two different climate-change scenarios: North Atlantic cooling representative of Heinrich events, and increased greenhouse gas (GHG) forcing. The effect of North Atlantic cooling is studied using a coupled regional model with comparatively high resolution that successfully simulates Central American gap winds and other important aspects of the region. Cooler North Atlantic sea surface temperature (SST) in this model leads to a regional decrease of atmospheric moisture but also to an increase in wind speed across Central America via an anomalous pressure gradient. The latter effect dominates, resulting in a 0.13 Sv (1 Sv = 10{sup 6} m{sup 3} s{sup -1}) increase in overall moisture transport to the Pacific basin. In fresh water forcing simulations with four different general circulation models, the wind speed effect is also present but not strong enough to completely offset the effect of moisture decrease except in one model. The influence of GHG forcing is studied using simulations from the Intergovernmental Panel on Climate Change archive. In these simulations atmospheric moisture increases globally, resulting in an increase of moisture transport by 0.25 Sv from the Atlantic to Pacific. Thus, in both scenarios, moisture transport changes act to stabilize the thermohaline circulation. The notion that the Andes effectively block moisture transport from the Atlantic to the Pacific basin is not supported by the simulations and atmospheric reanalyses examined here. This indicates that such a blocking effect does not exist or else that higher resolution is needed to adequately represent the steep orography of the Andes. (orig.)

  17. Organic matter in eolian dusts over the Atlantic Ocean

    Science.gov (United States)

    Simoneit, B. R. T.

    1977-01-01

    The elemental and mineralogical composition and the microfossil and detritus content of particulate fallout from the lower troposphere over the Atlantic Ocean have been extensively documented in earlier work, and it was possible to ascribe terrigenous source areas to such fallout. A brief review of the organic geochemistry of eolian dusts is also presented here. The lipids of eolian dusts sampled from the air mass over the eastern Atlantic from about 35 deg N to 30 deg S were analyzed here. These lipids consisted mainly of normal alkanes, carboxylic acids and alcohols. The n-alkanes were found to range from n-C23 to n-C35 with high CPI values and maximizing at n-C27 in the North Atlantic, at n-C29 in the equatorial Atlantic and at n-C31 in the South Atlantic. The n-fatty acids had mostly bimodal distributions, ranging from n-C12 to n-C30 (high CPI), with maxima at n-C16 and in the northern samples at n-C24 and in the southern samples at n-C26. The n-alcohols ranged from n-C12 to n-C32, with high CPI values and maxima mainly at n-C28. The compositions of these lipids indicated that their terrigenous sources were comprised mainly of higher plant vegetation and desiccated lacustrine mud flats on the African continent.

  18. Comparative visual ecophysiology of mid-Atlantic temperate reef fishes

    Directory of Open Access Journals (Sweden)

    Andrij Z. Horodysky

    2013-11-01

    The absolute light sensitivities, temporal properties, and spectral sensitivities of the visual systems of three mid-Atlantic temperate reef fishes (Atlantic spadefish [Ephippidae: Chaetodipterus faber], tautog [Labridae: Tautoga onitis], and black sea bass [Serranidae: Centropristis striata] were studied via electroretinography (ERG. Pelagic Atlantic spadefish exhibited higher temporal resolution but a narrower dynamic range than the two more demersal foragers. The higher luminous sensitivities of tautog and black sea bass were similar to other benthic and demersal coastal mid-Atlantic fishes. Flicker fusion frequency experiments revealed significant interspecific differences at maximum intensities that correlated with lifestyle and habitat. Spectral responses of the three species spanned 400–610 nm, with high likelihood of cone dichromacy providing the basis for color and contrast discrimination. Significant day-night differences in spectral responses were evident in spadefish and black sea bass but not tautog, a labrid with characteristic structure-associated nocturnal torpor. Atlantic spadefish responded to a wider range of wavelengths than did deeper-dwelling tautog or black sea bass. Collectively, these results suggest that temperate reef-associated fishes are well-adapted to their gradient of brighter to dimmer photoclimates, representative of their unique ecologies and life histories. Continuing anthropogenic degradation of water quality in coastal environments, at a pace faster than the evolution of visual systems, may however impede visual foraging and reproductive signaling in temperate reef fishes.

  19. Marine ecosystem response to the Atlantic Multidecadal Oscillation.

    Directory of Open Access Journals (Sweden)

    Martin Edwards

    Full Text Available Against the backdrop of warming of the Northern Hemisphere it has recently been acknowledged that North Atlantic temperature changes undergo considerable variability over multidecadal periods. The leading component of natural low-frequency temperature variability has been termed the Atlantic Multidecadal Oscillation (AMO. Presently, correlative studies on the biological impact of the AMO on marine ecosystems over the duration of a whole AMO cycle (∼60 years is largely unknown due to the rarity of continuously sustained biological observations at the same time period. To test whether there is multidecadal cyclic behaviour in biological time-series in the North Atlantic we used one of the world's longest continuously sustained marine biological time-series in oceanic waters, long-term fisheries data and historical records over the last century and beyond. Our findings suggest that the AMO is far from a trivial presence against the backdrop of continued temperature warming in the North Atlantic and accounts for the second most important macro-trend in North Atlantic plankton records; responsible for habitat switching (abrupt ecosystem/regime shifts over multidecadal scales and influences the fortunes of various fisheries over many centuries.

  20. Nutrient regimes control phytoplankton ecophysiology in the South Atlantic

    Directory of Open Access Journals (Sweden)

    T. J. Browning

    2013-07-01

    Full Text Available Fast Repetition Rate fluorometry (FRRf measurements of phytoplankton photophysiology from an across-basin South Atlantic cruise (as part of the GEOTRACES programme characterized two dominant ecophysiological regimes which were interpreted on the basis of nutrient limitation. South of the South Subtropical Convergence (SSTC in the northern sub-Antarctic sector of the Antarctic Circumpolar Current (ACC in the Eastern Atlantic Basin, waters are characterized by elevated chlorophyll concentrations, a dominance by larger phytoplankton cells, and low apparent photochemical efficiency (Fv / Fm. Shipboard 24 h iron (Fe addition incubation experiments confirmed that Fe stress was primarily responsible for the low Fv / Fm, with Fe addition to these waters, either within the artificial bottle additions or naturally occurring downstream enrichment from Gough Island, significantly increasing Fv / Fm values. Satellite images suggest a broader region of enhanced chlorophyll concentrations around the SSTC in the Western Atlantic relative to the Eastern Atlantic: hypothesized to be a result of higher iron supply from the South American continent. To the north of the SSTC at the southern boundary of the South Atlantic Gyre, phytoplankton are characterized by high values of Fv / Fm which, coupled with the low macronutrient concentrations and increased presence of picocyanobacteria, are interpreted as conditions of Fe replete, balanced macronutrient-limited growth. Spatial correlation was found between Fv / Fm and Fe:nitrate ratios, supporting the suggestion that the relative supply ratios of these two nutrients can control patterns of limitation and consequently the ecophysiology of phytoplankton in subtropical gyre and ACC regimes.

  1. 76 FR 31941 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; Horseshoe Crabs; Application...

    Science.gov (United States)

    2011-06-02

    ... National Oceanic and Atmospheric Administration RIN 0648-XW53 Atlantic Coastal Fisheries Cooperative Management Act Provisions; Horseshoe Crabs; Application for Exempted Fishing Permit AGENCY: National Marine... otherwise restricted by the regulations promulgated under the Atlantic Coastal Fisheries...

  2. 75 FR 31421 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; Application for Exempted...

    Science.gov (United States)

    2010-06-03

    ... National Oceanic and Atmospheric Administration RIN 0648-XW53 Atlantic Coastal Fisheries Cooperative Management Act Provisions; Application for Exempted Fishing Permit; Horseshoe Crabs AGENCY: National Marine... otherwise restricted by the regulations promulgated under the Atlantic Coastal Fisheries...

  3. 78 FR 29331 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; Horseshoe Crabs; Application...

    Science.gov (United States)

    2013-05-20

    ... National Oceanic and Atmospheric Administration RIN 0648-XC689 Atlantic Coastal Fisheries Cooperative... otherwise restricted by the regulations promulgated under the Atlantic Coastal Fisheries Cooperative... Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce....

  4. 77 FR 55457 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; Horseshoe Crabs; Application...

    Science.gov (United States)

    2012-09-10

    ... National Oceanic and Atmospheric Administration RIN 0648-XC220 Atlantic Coastal Fisheries Cooperative... otherwise restricted by the regulations promulgated under the Atlantic Coastal Fisheries Cooperative... Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce....

  5. 76 FR 22875 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; General Provisions for Domestic...

    Science.gov (United States)

    2011-04-25

    ... National Oceanic and Atmospheric Administration RIN 0648-XA355 Atlantic Coastal Fisheries Cooperative... Permits AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration... resulting data would be utilized by NJ DFW staff, Atlantic States Marine Fisheries Commission...

  6. 75 FR 34092 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; Weakfish Fishery

    Science.gov (United States)

    2010-06-16

    ... National Oceanic and Atmospheric Administration 50 CFR Part 697 RIN 0648-AY41 Atlantic Coastal Fisheries Cooperative Management Act Provisions; Weakfish Fishery AGENCY: National Marine Fisheries Service (NMFS.... Such action is authorized under the Atlantic Coastal Fisheries Cooperative Management Act...

  7. 78 FR 51131 - Fisheries of the Northeastern United States; Atlantic Coastal Fisheries Cooperative Management...

    Science.gov (United States)

    2013-08-20

    ... United States; Atlantic Coastal Fisheries Cooperative Management Act Provisions; American Lobster Fishery AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce. ACTION: Advance notice of proposed rulemaking. SUMMARY: Based on Atlantic States Marine...

  8. Inventory of Atlantic White-Cedar Remnant Stands in North Carolina

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report addresses Atlantic white cedar swamp restoration in North Carolina refuges. The ecology, use, and historical distribution of Atlantic white-cedar (AWC)...

  9. Outer Continental Shelf Oil and Natural Gas Wells - Atlantic Region NAD83

    Data.gov (United States)

    Bureau of Ocean Energy Management, Department of the Interior — This data set contains surface locations for oil and gas wells located in the Atlantic federal waters. All wells in the Atlantic Region were completed and abandoned...

  10. 77 FR 70149 - Mid-Atlantic Fishery Management Council (MAFMC); Public Meetings

    Science.gov (United States)

    2012-11-23

    ... National Oceanic and Atmospheric Administration Mid-Atlantic Fishery Management Council (MAFMC); Public... (NOAA), Commerce. ACTION: Notice of public meetings. SUMMARY: The Mid-Atlantic Fishery Management Council (Council) and its Visioning and Strategic Planning ] Working Group will hold public...

  11. Seasonal Variability of South Atlantic Central Water

    Science.gov (United States)

    Nobrega Passos, E.; de Freitas Assad, L.; Landau, L.

    2013-05-01

    The South Atlantic Ocean (SAO) is constituted by different density water masses. Among these, the South Atlantic Central Water (SACW) is formed on the Brazil-Falkland Confluence region (BFC) and once formed, it becomes part of the Subtropical Gyre. When approaching again the Brazilian coast, this water mass bifurcates next to São Tomé Cape and part of it flows to the North and part to the South. There is another bifurcation that formed the sub-gyre of the SAO and occurs near 30°S. This work aims to analyze the seasonal variability associated to the SACW trajectory on the SAO basin. To achieve this goal, ECCO2 project's time series of prognostic fields were analysed. The parameters evaluated were temperature, salinity and the zonal and meridional velocity components in averaged monthly fields between January 1992 and November 2010. First a climatological year was calculated and was composed by means from all time series for each month. And second, it was estimate seasonally means for the south hemisphere to summer, autumn, winter and springer. For the analysis, the SACW was separated from the rest of the water masses by isolating it for its temperature, salinity and density index. Then the volume transport (VT) was calculated for seven different sections: A (10°S and 36°W-30°W), B (35°S and 55°W-45°W), C (40°W and 37°S-43°S), D (34°S and 7°E-20°E), E (20°E and 34°S-45°S), F (20°W and 27°S-33°S) and G (10°W and 20°S-25°S). The VT integrated on the water column occupied by SACW was calculated from the zonal and meridional velocities. The analysis showed that the VT balance between the sections is consistent with the climatologic analysis, according to scientific references. The analysis of the climatological VT showed that the VT field integrated in SAWC levels is also consistent with scientific reference. On the seasonal analysis, the sections A and F show a stronger VT during autumn. Since section A is formed from part of the flux of section

  12. Ocean impact on decadal Atlantic climate variability revealed by sea-level observations

    OpenAIRE

    McCarthy, Gerard D.; Haigh, Ivan D.; Hirschi, Joël J.-M.; Grist, Jeremy P.; Smeed, David A.

    2015-01-01

    Decadal variability is a notable feature of the Atlantic Ocean and the climate of the regions it influences. Prominently, this is manifested in the Atlantic Multidecadal Oscillation (AMO) in sea surface temperatures. Positive (negative) phases of the AMO coincide with warmer (colder) North Atlantic sea surface temperatures. The AMO is linked with decadal climate fluctuations, such as Indian and Sahel rainfall1, European summer precipitation2, Atlantic hurricanes3 and variations in global temp...

  13. North Atlantic multidecadal variability in coupled climate models - Mechanisms and responses

    OpenAIRE

    Medhaug, Iselin

    2011-01-01

    Global atmosphere-ocean general circulation models have been used to investigate mechanisms controlling the North Atlantic low-frequency variability, with the focus on the Atlantic Meridional Overturning Circulation, the Subpolar Gyre dynamics and the North Atlantic basin scale sea surface temperatures, called the Atlantic Multidecadal Oscillation. The understanding of the dynamics of, and mechanisms behind the variability in these components of the climate system are of great ...

  14. Influence of the North Atlantic Oscillation on the Canary Islands precipitation

    OpenAIRE

    García Herrera, Ricardo; Gallego Puyol, David; Hernández Martín, Emiliano; Gimeno, Luis; Ribera Rodríguez, Pedro

    2001-01-01

    The aim of this paper is to investigate the relationship between the Canary Island rainfall and the Atlantic large-scale circulation, characterized by the North Atlantic oscillation (NAO) index. The Canary Islands are located in the Atlantic subtropical belt under the direct influence of the Azores high and the trade winds. Their steep orography makes the islands very sensitive to small variations in a synoptic situation, thus providing an excellent natural observatory for the North Atlantic ...

  15. Role of the Southern Ocean in setting the Atlantic stratification and meridional overturning circulation

    OpenAIRE

    Kamenkovich, Igor; Radko, Timour

    2011-01-01

    This study examines the importance of the Southern Ocean (SO) stratification in determining the upper cell of the Atlantic meridional overturning circulation (MOC) and stratification. Main results are based on a suite of idealized numerical simulations of the Atlantic with the prescribed density structure at the Atlantic southern boundary, intended to explore the importance of various factors. The results demonstrate that the density distribution at the SO-Atlantic boundary is the...

  16. Array Analysis of North Atlantic Microseisms

    Science.gov (United States)

    Craig, David; Bean, Chris; Möllhoff, Martin; Donne, Sarah; Lokmer, Ivan; Le Pape, Florian

    2016-04-01

    Oceans generate persistent low frequency background seismic signals known as microseisms through a mechanical coupling with the Earth's crust. Microseism energy originates as regions of low barometric pressure (depressions) over the oceans where it is transmitted to the sea-floor and propagates as elastic energy in the Earths crust. Consequently microseisms carry important meteorological information relating to both the atmosphere and the hydrosphere. The significance of microseisms as climate indicators has previously been investigated in several studies (Essen et al., 1999; Aster et al., 2010) and to estimate ocean wave parameters using onshore seismometer data (Bromirski et al., 1999). Also many modern seismological methods make use of microseism signals, for example "noise tomography" (Shapiro et al., 2005); spectral ratio techniques ; and cross-correlation techniques (Wapenaar et al., 2011; Brenguier et al., 2014). The continental shelf near Ireland is a known generation are for microseisms and an important region for European weather forecasting and climate studies. There has also been seismometers in the region since the 1960s. There is a single station in Valentia observatory in south-west Ireland and a small scale seismic array in Scotland which offer potential climate records for the region. To make use of this information it is first necessary to understand how microseisms recorded in Ireland relate to the local ocean wavefield. The WAVEOBS project was set established with three primary goals; to get a better fundamental understanding of microseism sources; to investigate the use of ocean generated microseisms as real time ocean wave height data; and to investigate their use as a climate proxy. Using spectral analysis and array methods the microseism wavefield in the North-East Atlantic near Ireland is described with reference to the ocean wavefield.

  17. Preformed Nitrate in the Glacial North Atlantic

    Science.gov (United States)

    Homola, K.; Spivack, A. J.; D'Hondt, S.; Estes, E. R.; Insua, T. L.; McKinley, C. C.; Murray, R. W.; Pockalny, R. A.; Robinson, R. S.; Sauvage, J.

    2015-12-01

    Atmospheric CO2 abundances are highly correlated with global temperature variations over the past 800,000 years. Consequently, understanding the feedbacks between climate and CO2 is important for predictions of future climate. Leading hypotheses to explain this feedback invoke changes in ocean biology, circulation, chemistry, and/or gas exchange rates to trap CO2 in the deep ocean, thereby reducing the greenhouse effect of CO2 in the atmosphere. To test these hypotheses, we use sediment pore water profiles of dissolved nitrate and oxygen to reconstruct paleo-preformed nitrate concentrations at two deep-water sites in the western North Atlantic (23°N 57°W, 5557 m water depth; 30°N 58°W, 5367 m water depth). Preformed nitrate increases down-core to 22.7 μM (25.6 m core depth) at the northern site, and to 28.5 μM (27.8 m core depth) at the southern site. The large preformed nitrate gradient between these sites reveals a paleo-boundary between a southern water source high in preformed nitrate and a northern water source with lower concentrations, similar to today's ocean. However, the boundary between these water masses occurs north of where their modern counterparts meet, indicating that Antarctic Bottom Water (AABW) extended farther north during the Last Glacial Maximum (LGM). In addition, the southern source had a higher preformed nitrate concentration than today's AABW (25 μM), contradicting hypotheses that nutrient utilization was more efficient in the Southern Ocean deep-water formation regions during the LGM. Comparison to our previous Pacific data reveals that the average preformed nitrate concentration of the deep ocean was slightly higher during the LGM than today. This result implies that the CO2-climate feedback was not principally due to more efficient nitrate utilization.

  18. Saharan dust transport and deposition towards the Tropical Northern Atlantic

    Directory of Open Access Journals (Sweden)

    K. Schepanski

    2008-08-01

    Full Text Available We present a study of Saharan dust export towards the tropical North Atlantic using the regional dust emission, transport and deposition model LM-MUSCAT. Horizontal and vertical distribution of dust optical thickness, concentration, and dry and wet deposition rates are used to describe seasonality of dust export and deposition towards the eastern Atlantic for three exemplary months in different seasons. Deposition rates strongly depend on the vertical dust distribution, which differs with seasons. Furthermore the contribution of dust originating from the Bodélé Depression to Saharan dust over the Atlantic is investigated. A maximum contribution of Bodélé dust transported towards the Cape Verde Islands is evident in winter when the Bodélé source area is most active and dominant with regard activation frequency and dust emission. Limitations of using satellite retrievals to estimate dust deposition are highlighted.

  19. South Scandinavian joints and Alpine/Atlantic-ridge tectonics

    Directory of Open Access Journals (Sweden)

    A. E. Scheidegger

    2000-06-01

    Full Text Available Field observations and studies of the joints and dykes in an area shed light on its younger tectonic development; thus, joint orientations measured in Southern Sweden and in Norway have been statistically studied and compared regarding their tectonic significance with studies from Europe and the mid-Atlantic ridge. The present investigation indicates that the surface joint systems in Sweden agree with those in Europe; they are the result of the intracratonic stress field and the mechanical response associated with the Alpine orogeny. The stress systems in Southern Norway, on the other hand, are the result of the ongoing extensional or wrench-fault tectonism in the Atlantic crust associated with the stresses near the mid-Atlantic ridge, which act normally to the contiguous coastlines from Scandinavia to France, Portugal and North Africa.

  20. Towards a governance agenda for the emerging Atlantic Hemisphere

    Directory of Open Access Journals (Sweden)

    Daniel S. Hamilton

    2013-09-01

    Full Text Available The Atlantic Basin is re-emerging as an important subsystem within the global political economy: inter-linked flows of people and energy, money and weapons,goods and services, technology and terror,drugs and crime; greater access to each other’s markets, resources, and talent. Yet,growing interdependencies gene-rate new vulnerabilities and challenges: cooperation over resources and energy connections; promotion of trade and investment; migration and integration; building resilient societies; enhancement of good governance; investment in human development; and the fight against transnational criminal organisations and their growing links to terrorists and insurgents. However, while governance mechanisms and diplomatic cooperation based on a pan-Atlantic framework are in their infancy, a host of developments suggests that broadranging, interwoven hemispheric cooperation may be possible. In fact, the Atlantic Basin may emerge as a global laboratory for interregional, networked governance between developed and emerging countries.

  1. Cenozoic uplift and subsidence in the North Atlantic region

    DEFF Research Database (Denmark)

    Anell, Ingrid Anna Margareta; Thybo, Hans; Artemieva, Irina

    2009-01-01

    studies, mass balance calculations and extrapolation of seismic profiles to onshore geomorphological features. The integration of about 200 published results reveal a clear pattern of topographic changes in the North Atlantic region during the Cenozoic: (1) The first major phase of Cenozoic regional......The topographic evolution of the "passive" margins of the North Atlantic during the last 65 Myr is the subject of extensive debate due to inherent limitations of the geological, geomorphological and geophysical methods used for studies of uplift and subsidence. We have compiled a database of sign......, time and amplitude (where possible) of topographic changes in the North Atlantic region during the Cenozoic (65-0 Ma). Our compilation is based on published results from reflection seismic studies, AFT (apatite fission track) studies, VR (vitrinite reflectance) trends, maximum burial, sediment supply...

  2. Atlantic surfclam connectivity within the Middle Atlantic Bight: Mechanisms underlying variation in larval transport and settlement

    Science.gov (United States)

    Zhang, Xinzhong; Munroe, Daphne; Haidvogel, Dale; Powell, Eric N.

    2016-05-01

    Larval transport and settlement have been shown in various studies to be essential in determining population abundance and connectivity for benthic invertebrates. This transport is influenced by both the physical environment and biological behavior. The Atlantic surfclam, Spisula solidissima, is a commercially important benthic invertebrate fishery species along the U.S northeastern coast. In this study, a physical circulation model is coupled to a surfclam larval model to investigate the dynamics of larval transport and settlement within the Middle Atlantic Bight (MAB) shelf in 2006. The main physical mechanisms causing variability in larval transport and settlement are also examined. Model results show that surfclam larvae released from July to early October experience relatively larger settlement rates, due to higher average temperatures experienced by larvae. Larval along-shore transport exhibits a mean down-coast pattern following the coastal current from the northeast to the southwest, with most high-frequency (period of 2-10 days) variations caused by fluctuations in the along-shore surface wind stress, and with seasonal variations speculated to be driven mainly by changes in the across-shelf density gradient. Larval across-shelf movement is highly correlated with the along-shore surface wind stress mediated by coastal upwelling and downwelling episodes, but the correlation is further dependent on the vertical distribution of the larvae, particularly their position relative to the thermocline. Most surfclam larvae released from the Middle Atlantic shelf stay below the thermocline and experience a net onshore transport during the summer-stratified season when upwelling-favorable wind forcing dominates. A proposed critical value of water temperature at the thermocline successfully regulates the observed patterns of vertical distribution of surfclam larvae and their across-shelf movement off the New Jersey and South Virginia shelves; that is, when the water

  3. The role of volume-sensitive ion transport systems in regulation of epithelial transport

    DEFF Research Database (Denmark)

    Hoffmann, Else Kay; Schettino, T; Marshall, W S

    2007-01-01

    This review focuses on using the knowledge on volume-sensitive transport systems in Ehrlich ascites tumour cells and NIH-3T3 cells to elucidate osmotic regulation of salt transport in epithelia. Using the intestine of the European eel (Anguilla anguilla) (an absorptive epithelium of the type......-induced activation of NKCC2 involves an interaction between the cytoskeleton and protein phosphorylation events via PKC and myosin light chain kinase (MLCK). Killifish (Fundulus heteroclitus) opercular epithelium is a Cl(-)-secreting epithelium of the type described in exocrine glands, having a CFTR channel...

  4. On multiple equilibria of the global ocean circulation and the preference for North Atlantic sinking

    NARCIS (Netherlands)

    Huisman, S.E.

    2010-01-01

    In the ocean circulation there is the peculiar feature that heat transport is northwards throughout the entire Atlantic ocean. This means that the Atlantic heat transport in the southern hemisphere is towards the equator. Also, the heat transport in the Atlantic is much larger that in the Pacific. T

  5. Atlantic update, July 1986--June 1990: Outer Continental Shelf oil and gas activities

    Energy Technology Data Exchange (ETDEWEB)

    Karpas, R.M.; Gould, G.J.

    1990-10-01

    This report describes outer continental shelf oil and gas activities in the Atlantic Region. This edition of the Atlantic Update includes an overview of the Mid-Atlantic Planning Area and a summary of the Manteo Prospect off-shore North Carolina. 6 figs., 8 tabs.

  6. 77 FR 32420 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; American Lobster Fishery

    Science.gov (United States)

    2012-06-01

    ... National Oceanic and Atmospheric Administration 50 CFR Part 697 RIN 0648-BA56 Atlantic Coastal Fisheries Cooperative Management Act Provisions; American Lobster Fishery AGENCY: National Marine Fisheries Service... section 803(b) of the Atlantic Coastal Fisheries Cooperative Management Act (Atlantic Coastal Act) 16...

  7. 75 FR 8673 - Mid-Atlantic Fishery Management Council; Public Meeting

    Science.gov (United States)

    2010-02-25

    ... National Oceanic and Atmospheric Administration RIN: 0648-XU57 Mid-Atlantic Fishery Management Council... Administration (NOAA), Commerce. ACTION: Notice of a public meeting. SUMMARY: The Mid-Atlantic Fishery Management... Leadership and Sustainability Forum (FLSF), the Atlantic States Marine Fisheries Commission (ASMFC), and...

  8. 76 FR 63615 - Atlantic Path 15, LLC; Notice of Initiation of Proceeding and Refund Effective Date

    Science.gov (United States)

    2011-10-13

    ... Energy Regulatory Commission Atlantic Path 15, LLC; Notice of Initiation of Proceeding and Refund... determine the justness and reasonableness of Atlantic Path 15, LLC's proposed rate reduction to its transmission revenue requirement. Atlantic Path 15, LLC, 135 FERC ] 61,037 (2011). The refund effective date...

  9. 76 FR 64074 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2011-10-17

    ... National Oceanic and Atmospheric Administration RIN 0648-XA670 Schedules for Atlantic Shark Identification... Shark Identification workshop scheduled for November 17, 2011, in Charleston, SC, has been changed. This.... Atlantic Shark Identification workshops are mandatory for Atlantic Shark Dealer permit holders or...

  10. 78 FR 72070 - Notice of Availability of Record of Decision for Atlantic Fleet Training and Testing

    Science.gov (United States)

    2013-12-02

    ... Department of the Navy Notice of Availability of Record of Decision for Atlantic Fleet Training and Testing... Atlantic Fleet study area as described in Alternative 2 for the proposed action. Under Alternative 2, the... for Atlantic Fleet Training and Testing, dated August 2013 and supporting documents. Single copies...

  11. Efficacy and toxicity of iodine disinfection of Atlantic salmon eggs

    Science.gov (United States)

    Chalupnicki, M.A.; Ketola, H.G.; Starliper, C.E.; Gallagher, D.

    2011-01-01

    Recent interest in the restoration of Atlantic salmon Salmo salar in the Great Lakes has given rise to new culture techniques and management programs designed to reduce pathogen transmission while stabilizing and enhancing wild populations. We examined the toxicity of iodine to Atlantic salmon eggs and its effectiveness as a disinfectant against bacteria on egg surfaces. We spawned and fertilized eight gravid Atlantic salmon from Cayuga Lake, New York, and exposed their eggs to 10 concentrations of iodine (5, 10, 50, 75, 100, 500, 750, 1,000, 5,000, and 7,500 mg/L) for 30 min during water hardening. An additional subsample of unfertilized eggs was also exposed to some of the same concentrations of iodine (5, 10, 50, 75, and 100 mg/L) to determine the efficiency of disinfection. Viable eggs were only obtained from four females. Survival of eggs to the eyed stage and hatch tended to be reduced at iodine concentrations of 50 and 75 mg/L and was significantly reduced at concentrations of 100 mg/L iodine or more. We calculated the concentrations of iodine that killed 50% of the Atlantic salmon eggs at eye-up and hatch to be 175 and 85 mg/L, respectively. Aeromonas veronii, A. schubertii, A. hydrophila, A. caviae, Plesiomonas shiggeloides, and Citrobacter spp. were the predominant bacteria present on the surface of green eggs and were significantly reduced by an iodine immersion. The use of iodine as a disinfectant on Atlantic salmon eggs was effective at low concentrations (50–75 mg/L), for which toxicity to Atlantic salmon was minimal.

  12. Enhanced warming of the Northwest Atlantic Ocean under climate change

    Science.gov (United States)

    Saba, Vincent S.; Griffies, Stephen M.; Anderson, Whit G.; Winton, Michael; Alexander, Michael A.; Delworth, Thomas L.; Hare, Jonathan A.; Harrison, Matthew J.; Rosati, Anthony; Vecchi, Gabriel A.; Zhang, Rong

    2016-01-01

    The Intergovernmental Panel on Climate Change (IPCC) fifth assessment of projected global and regional ocean temperature change is based on global climate models that have coarse (˜100 km) ocean and atmosphere resolutions. In the Northwest Atlantic, the ensemble of global climate models has a warm bias in sea surface temperature due to a misrepresentation of the Gulf Stream position; thus, existing climate change projections are based on unrealistic regional ocean circulation. Here we compare simulations and an atmospheric CO2 doubling response from four global climate models of varying ocean and atmosphere resolution. We find that the highest resolution climate model (˜10 km ocean, ˜50 km atmosphere) resolves Northwest Atlantic circulation and water mass distribution most accurately. The CO2 doubling response from this model shows that upper-ocean (0-300 m) temperature in the Northwest Atlantic Shelf warms at a rate nearly twice as fast as the coarser models and nearly three times faster than the global average. This enhanced warming is accompanied by an increase in salinity due to a change in water mass distribution that is related to a retreat of the Labrador Current and a northerly shift of the Gulf Stream. Both observations and the climate model demonstrate a robust relationship between a weakening Atlantic Meridional Overturning Circulation (AMOC) and an increase in the proportion of Warm-Temperate Slope Water entering the Northwest Atlantic Shelf. Therefore, prior climate change projections for the Northwest Atlantic may be far too conservative. These results point to the need to improve simulations of basin and regional-scale ocean circulation.

  13. Atlantic Ocean CARINA data: overview and salinity adjustments

    Directory of Open Access Journals (Sweden)

    T. Tanhua

    2009-08-01

    Full Text Available Water column data of carbon and carbon-relevant hydrographic and hydrochemical parameters from 188 previously non-publicly available cruise data sets in the Arctic, Atlantic and Southern Ocean have been retrieved and merged into a new database: CARINA (CARbon IN the Atlantic. The data have gone through rigorous quality control procedures to assure the highest possible quality and consistency. The data for the pertinent parameters in the CARINA database were objectively examined in order to quantify systematic differences in the reported values, i.e. secondary quality control. Systematic biases found in the data have been corrected in the data products, i.e. three merged data files with measured, calculated and interpolated data for each of the three CARINA regions, i.e. Arctic, Atlantic and Southern Ocean. Ninety-eight of the cruises in the CARINA database were conducted in the Atlantic Ocean, defined here as the region south of the Greenland-Iceland-Scotland Ridge and north of about 30° S. Here we present an overview of the Atlantic Ocean synthesis of the CARINA data and the adjustments that were applied to the data product. We also report details of the secondary QC for salinity for this data set. Procedures of quality control – including crossover analysis between stations and inversion analysis of all crossover data – are briefly described. Adjustments to salinity measurements were applied to the data from 10 cruises in the Atlantic Ocean region. Based on our analysis we estimate the internal accuracy of the CARINA-ATL salinity data to be 4.1 ppm. With these adjustments the CARINA database is consistent both internally as well as with GLODAP data, an oceanographic data set based on the World Hydrographic Program in the 1990s (Key et al., 2004, and is now suitable for accurate assessments of, for example, oceanic carbon inventories and uptake rates and for model validation.

  14. Atlantic Ocean CARINA data: overview and salinity adjustments

    Energy Technology Data Exchange (ETDEWEB)

    Tanhua, T. [IFM-GEOMAR, Leibniz Institute for Marine Sciences, Chemical Oceanography, Kiel, Germany; Steinfeldt, R. [University of Bremen, Bremen, Germany; Key, Robert [Princeton University; Brown, P. [University of East Anglia, Norwich, United Kingdom; Gruber, N. [ETH Zurich, Switzerland; Wanninkhof, R. [Atlantic Oceanographic & Meteorological Laboratory, NOAA; Perez, F.F. [Instituto de Investigaciones Marinas de Vigo, CSIC, Vigo, Spain; Kortzinger, A. [IFM-GEOMAR, Leibniz Institute for Marine Sciences, Chemical Oceanography, Kiel, Germany; Velo, A. [Instituto de Investigaciones Marinas de Vigo, CSIC, Vigo, Spain; Schuster, U. [University of East Anglia, Norwich, United Kingdom; Van Heuven, S. [University of Groningen, The Netherlands; Bullister, J.L. [NOAA Pacific Marine Environmental Laboratory; Stendardo, I. [ETH Zurich, Switzerland; Hoppema, M. [Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany; Olsen, Are [Bjerknes Centre for Climate Research, UNIFOB AS, Bergen, Norway; Kozyr, Alexander [ORNL; Pierrot, D. [Cooperative Institute of Marine and Atmospheric Sciences, U. Miami; Schirnick, C. [IFM-GEOMAR, Leibniz Institute for Marine Sciences, Chemical Oceanography, Kiel, Germany; Wallace, D.W.R. [IFM-GEOMAR, Leibniz Institute for Marine Sciences, Chemical Oceanography, Kiel, Germany

    2010-01-01

    Water column data of carbon and carbon-relevant hydrographic and hydrochemical parameters from 188 previously non-publicly available cruise data sets in the Arctic Mediterranean Seas, Atlantic and Southern Ocean have been retrieved and merged into a new database: CARINA (CARbon dioxide IN the Atlantic Ocean). The data have gone through rigorous quality control procedures to assure the highest possible quality and consistency. The data for the pertinent parameters in the CARINA database were objectively examined in order to quantify systematic differences in the reported values, i.e. secondary quality control. Systematic biases found in the data have been corrected in the three data products: merged data files with measured, calculated and interpolated data for each of the three CARINA regions, i.e. the Arctic Mediterranean Seas, the Atlantic and the Southern Ocean. These products have been corrected to be internally consistent. Ninety-eight of the cruises in the CARINA database were conducted in the Atlantic Ocean, defined here as the region south of the Greenland-Iceland-Scotland Ridge and north of about 30 S. Here we present an overview of the Atlantic Ocean synthesis of the CARINA data and the adjustments that were applied to the data product. We also report the details of the secondary QC (Quality Control) for salinity for this data set. Procedures of quality control including crossover analysis between stations and inversion analysis of all crossover data are briefly described. Adjustments to salinity measurements were applied to the data from 10 cruises in the Atlantic Ocean region. Based on our analysis we estimate the internal consistency of the CARINA-ATL salinity data to be 4.1 ppm. With these adjustments the CARINA data products are consistent both internally was well as with GLODAP data, an oceanographic data set based on the World Hydrographic Program in the 1990s, and is now suitable for accurate assessments of, for example, oceanic carbon inventories

  15. CARINA TCO2 data in the Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    R. Wanninkhof

    2010-01-01

    Full Text Available Water column data of carbon and carbon-relevant hydrographic and hydrochemical parameters from 188 cruises in the Arctic, Atlantic and Southern Ocean have been retrieved and merged in a new data base: the CARINA (CARbon IN the Atlantic Project. These data have gone through rigorous quality control (QC procedures to assure the highest possible quality and consistency. Secondary quality control, which involved objective study of data in order to quantify systematic differences in the reported values, was performed for the pertinent parameters in the CARINA data base. Systematic biases in the data have been corrected in the data products. The products are three merged data files with measured, adjusted and interpolated data of all cruises for each of the three CARINA regions (Arctic, Atlantic and Southern Ocean. Ninety-eight cruises were conducted in the "Atlantic" defined as the region south of the Greenland-Iceland-Scotland Ridge and north of about 30° S. Here we report the details of the secondary QC which was done on the total dissolved inorganic carbon (TCO2 data and the adjustments that were applied to yield the final data product in the Atlantic. Procedures of quality control – including crossover analysis between stations and inversion analysis of all crossover data – are briefly described. Adjustments were applied to TCO2 measurements for 17 of the cruises in the Atlantic Ocean region. With these adjustments, the CARINA data base is consistent both internally as well as with GLODAP data, an oceanographic data set based on the WOCE Hydrographic Program in the 1990s, and is now suitable for accurate assessments of, for example, regional oceanic carbon inventories, uptake rates and model validation.

  16. CARINA TCO2 data in the Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    R. Wanninkhof

    2010-07-01

    Full Text Available Water column data of carbon and carbon-relevant hydrographic and hydrochemical parameters from 188 cruises in the Arctic Mediterranean Seas, Atlantic and Southern Ocean have been retrieved and merged in a new data base: the CARINA (CARbon IN the Atlantic Project. These data have gone through rigorous quality control (QC procedures so as to improve the quality and consistency of the data as much as possible. Secondary quality control, which involved objective study of data in order to quantify systematic differences in the reported values, was performed for the pertinent parameters in the CARINA data base. Systematic biases in the data have been tentatively corrected in the data products. The products are three merged data files with measured, adjusted and interpolated data of all cruises for each of the three CARINA regions (Arctic Mediterranean Seas, Atlantic and Southern Ocean. Ninety-eight cruises were conducted in the "Atlantic" defined as the region south of the Greenland-Iceland-Scotland Ridge and north of about 30° S. Here we report the details of the secondary QC which was done on the total dissolved inorganic carbon (TCO2 data and the adjustments that were applied to yield the final data product in the Atlantic. Procedures of quality control – including crossover analysis between stations and inversion analysis of all crossover data – are briefly described. Adjustments were applied to TCO2 measurements for 17 of the cruises in the Atlantic Ocean region. With these adjustments, the CARINA data base is consistent both internally as well as with GLODAP data, an oceanographic data set based on the WOCE Hydrographic Program in the 1990s, and is now suitable for accurate assessments of, for example, regional oceanic carbon inventories, uptake rates and model validation.

  17. Management of Atlantic walrus (Odobenus rosmarus rosmarus in the arctic Atlantic

    Directory of Open Access Journals (Sweden)

    Øystein Wiig

    2014-02-01

    Full Text Available We review the management of Atlantic walruses (Odobenus rosmarus rosmarus past and present in the four range states—Canada, Greenland, Norway and Russia—which have permanent populations of Atlantic walruses. Populations in all four countries have been depleted, although the extent of depletion is not well known. Inuit in Arctic Canada and Greenland hunt Atlantic walruses for subsistence while they have been protected at Svalbard (Norway since 1952 and in the western Russian Arctic since 1956. Since the second half of the 20th Century Canada and Greenland have increased protection of their walrus. Generally the number of walruses landed in Canada is governed by the number of hunters and/or people in the settlement and not by stock-specific quotas. Although quotas have been set in few communities, it is not known if they are adequate to prevent overhunting. A quota system for walrus hunting in Greenland began in 2006. The current control system is largely effective in ensuring the quotas are applied and that reporting is correct. Greenland currently sets quotas based on recommendations from scientific assessments using recent population estimates to allow population growth from a depleted population.  A challenge with respect to managing walrus hunting remains the variable and sometimes high rates of lost animals. Since the 1960s changes in socio-economics in hunting areas of Arctic Canada and Greenland (and the use of snowmobiles instead of dog sleds in Canada have led to a general decrease in interest in hunting of walruses and reduced harvest on walrus stocks in these countries. Although there is an active ongoing cooperation between Canada and Greenland scientists regarding assessments of shared populations of walruses currently there is no formal agreement between the two range states on co-management of shared stocks. Protection of walrus from other anthropogenic impacts generally focusses on large-scale industrial activity. The level

  18. The South Atlantic Anticyclone as a key player for the representation of the tropical Atlantic climate in coupled climate models

    Science.gov (United States)

    Cabos, William; Sein, Dmitry V.; Pinto, Joaquim G.; Fink, Andreas H.; Koldunov, Nikolay V.; Alvarez, Francisco; Izquierdo, Alfredo; Keenlyside, Noel; Jacob, Daniela

    2016-08-01

    The key role of the South Atlantic Anticyclone (SAA) on the seasonal cycle of the tropical Atlantic is investigated with a regionally coupled atmosphere-ocean model for two different coupled domains. Both domains include the equatorial Atlantic and a large portion of the northern tropical Atlantic, but one extends southward, and the other northwestward. The SAA is simulated as internal model variability in the former, and is prescribed as external forcing in the latter. In the first case, the model shows significant warm biases in sea surface temperature (SST) in the Angola-Benguela front zone. If the SAA is externally prescribed, these biases are substantially reduced. The biases are both of oceanic and atmospheric origin, and are influenced by ocean-atmosphere interactions in coupled runs. The strong SST austral summer biases are associated with a weaker SAA, which weakens the winds over the southeastern tropical Atlantic, deepens the thermocline and prevents the local coastal upwelling of colder water. The biases in the basins interior in this season could be related to the advection and eddy transport of the coastal warm anomalies. In winter, the deeper thermocline and atmospheric fluxes are probably the main biases sources. Biases in incoming solar radiation and thus cloudiness seem to be a secondary effect only observed in austral winter. We conclude that the external prescription of the SAA south of 20°S improves the simulation of the seasonal cycle over the tropical Atlantic, revealing the fundamental role of this anticyclone in shaping the climate over this region.

  19. The East Atlantic - West Russia Teleconnection in the North Atlantic: Climate Impact and Relation to Rossby Wave Propagation

    Science.gov (United States)

    Lim, Young-Kwon

    2014-01-01

    Large-scale winter teleconnection of the East Atlantic - West Russia (EA-WR) over the Atlantic and surrounding regions is examined in order to quantify its impacts on temperature and precipitation and identify the physical mechanisms responsible for its existence. A rotated empirical orthogonal function (REOF) analysis of the upper-tropospheric monthly height field captures successfully the EA-WR pattern and its interannual variation, with the North Atlantic Oscillation as the first mode. EA-WRs climate impact extends from eastern North America to Eurasia. The positive (negative) EA-WR produces positive (negative) temperature anomalies over the eastern US, western Europe and Russia east of Caspian Sea, with negative (positive) anomalies over eastern Canada, eastern Europe including Ural Mountains and the Middle East. These anomalies are largely explained by lower-tropospheric temperature advections. Positive (negative) precipitation anomalies are found over the mid-latitude Atlantic and central Russia around 60E, where lower-level cyclonic (anticyclonic) circulation anomaly is dominant. The eastern Canada and the western Europe are characterized by negative (positive) precipitation anomalies.The EA-WR is found to be closely associated with Rossby wave propagation. Wave activity fluxes show that it is strongly tied to large-scale stationary waves. Furthermore, a stationary wave model (SWM) forced with vorticity transients in the mid-latitude Atlantic (approximately 40N) or diabatic heat source over the subtropical Atlantic near the Caribbean Sea produces well-organized EA-WR-like wave patterns, respectively. Sensitivity tests with the SWM indicate improvement in the simulation of the EA-WR when the mean state is modified to have a positive NAO component that enhances upper-level westerlies between 40-60N.

  20. Extratropical Transitions in Atlantic Canada: Impacts and Adaptive Responses

    Science.gov (United States)

    Masson, Athena; Catto, Norm

    2013-04-01

    Cyclones originating over the tropical Atlantic may undergo the process of extratropical transition as they move northeastward along the coast of North America. Interaction with eastward-moving mid-latitude cyclones or frontal systems can result in the formation of spatially larger, more powerful storms, marked by frontal characteristics, changes (either increases or decreases) in wind speed and track velocity, and less predictable tracks coupled with increased precipitation and potential for storm surge. Of the 330 tropical cyclones formed over the North Atlantic from 1991 to 2011, 134 (40.6%) underwent partial or total extratropical transition. The dynamics and threats of extratropical transitions have not been extensively studied. Consequently, forecasters refer to approaching storms as "hurricanes," although they are frequently extratropical in character by the time they reach New York and New England, and almost always have undergone partial or complete transition before making landfall in Atlantic Canada. In rare instances, extratropical transitions may continue to progress eastwards across the North Atlantic. In a typical summer-autumn, Atlantic Canada is impacted by 5 to 7 storms of tropical origin. Due to variations in track and interaction to form extratropical transitions, the number of summer and early autumn storm events in Atlantic Canada is not linked to the total number of hurricanes in any specific year. Overall tropical cyclone frequency in the North Atlantic cannot be directly correlated with temperature variations, or with the frequency or magnitude of summer and early autumn storms in Atlantic Canada. Extratropical transition "Igor" directly impacted more than 40,000 km2 of eastern Newfoundland on 20-22 September 2010. Current estimates of damage to human property exceed 165 million, and one human life was lost. River flooding resulted from rainfall in excess of 150 mm/24 h in several locations, with peak stream flow locally exceeding 600 m3/s

  1. Relation between the wind stress curl in the North Atlantic and the Atlantic inflow to the Nordic Seas

    OpenAIRE

    Sandø, Anne Britt; Furevik, Tore

    2008-01-01

    In this study an isopycnic coordinate ocean model has been used to investigate the relationships between the North Atlantic wind stress curl (WSC) and the inflow of Atlantic water to the Nordic Seas. For the period 1995–2001, there is a maximum in the correlation between the zonally averaged WSC at 55!N and the inflow with a 15-month time lag, capturing a relation already found in observational data. In the model this relation is linked to the mixing along the western flank of the...

  2. 75 FR 10693 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Resources of the...

    Science.gov (United States)

    2010-03-09

    ..., Gulf of Mexico, and South Atlantic; Snapper-Grouper Resources of the South Atlantic; Trip Limit... . SUPPLEMENTARY INFORMATION: The snapper-grouper fishery of the South Atlantic is managed under the Fishery Management Plan for the Snapper- Grouper Resources of the South Atlantic (FMP). The FMP was prepared by...

  3. 78 FR 57337 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery Off the...

    Science.gov (United States)

    2013-09-18

    ..., 2011, NMFS published a notice of agency action (76 FR 78245) designating the South Atlantic Council as..., Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery Off the Southern Atlantic States; Amendment... Plan for the Snapper-Grouper Fishery of the South Atlantic Region (FMP) for review, approval,...

  4. 76 FR 59371 - Fisheries of the Caribbean, Gulf of Mexico and South Atlantic; Comprehensive Ecosystem-Based...

    Science.gov (United States)

    2011-09-26

    ... Bottom Habitats of the South Atlantic Region (Coral FMP); the FMP for Sargassum of the South Atlantic Region (Sargassum FMP); and the FMP for the Snapper-Grouper Fishery of the South Atlantic Region (Snapper... southern Atlantic states are managed under their respective FMPs. The Coral, Snapper-Grouper and...

  5. Population dynamics and fisheries assessment of the bigeye thresher (Alopias superciliosus) in the Atlantic: a comparison between North Atlantic and South Atlantic stocks

    OpenAIRE

    Carvalho, Joana Fernandez de

    2015-01-01

    Tese de doutoramento, Ciências do Mar, da Terra e do Ambiente (Biologia Pesqueira), Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2015 The bigeye thresher shark, Alopias supercilious is an oceanic pelagic shark, occasionally caught as bycatch in pelagic longline fisheries targeting tunas and swordfish in the Atlantic Ocean. It is particularly vulnerable to fishing pressure, with overexploitation occurring even at low levels of fishing, due to their slow growth, extremely low...

  6. Meridional carbon dioxide transport in the northern North Atlantic

    NARCIS (Netherlands)

    Stoll, M.H.C.; Aken, H.M. van; Baar, H.J.W. de; Boer, C.J. de

    1996-01-01

    Combination of estimated water transport and accurate measurements of total carbon dioxide (TCO2) on a hydrographic section at 58°N allows the assessment of meridional inorganic carbon transport in the northern North Atlantic Ocean. The transport has been decomposed into contributions from the large

  7. Global Warming Attenuates the Tropical Atlantic-Pacific Teleconnection.

    Science.gov (United States)

    Jia, Fan; Wu, Lixin; Gan, Bolan; Cai, Wenju

    2016-01-01

    Changes in global sea surface temperature (SST) since the end of last century display a pattern of widespread warming intercepted by cooling in the eastern equatorial Pacific and western coasts of the American continent. Studies have suggested that the cooling in the eastern equatorial Pacific may be partly induced by warming in the North Atlantic. However, it remains unknown how stable this inter-tropical teleconnection will be under global warming. Here we show that the inter-tropical teleconnection from the tropical Atlantic to Pacific weakens substantially as the CO2 concentration increases. This reduced impact is related to the El Niño-like warming of the tropical Pacific mean state, which leads to limited seasonal migration of the Pacific inter-tropical convergence zone (ITCZ) and weakened ocean heat transport. A fast decay of the tropical Atlantic SST anomalies in a warmer climate also contributes to the weakened teleconnection. Our study suggests that as greenhouse warming continues, the trend in the tropical Pacific as well as the development of ENSO will be less frequently interrupted by the Atlantic because of this attenuation. The weakened teleconnection is also supported by CMIP5 models, although only a few of these models can capture this inter-tropical teleconnection. PMID:26838053

  8. Structure of chymotrypsin variant B from Atlantic cod, Gadus morhua

    DEFF Research Database (Denmark)

    Leth-Larsen, Rikke; Asgeirsson, B; Thórólfsson, M;

    1996-01-01

    The amino-acid sequence of chymotrypsin variant B isolated from the pyloric caeca of Atlantic cod has been elucidated. The characterization of the primary structure is based on N-terminal Edman degradation and mass spectrometry of the native protein and enzymatically derived peptides. Chymotrypsi...

  9. Winter distribution of Calanus finmarchicus in the Northeast Atlantic

    DEFF Research Database (Denmark)

    Heath, M.R.; Fraser, J.G.; Gislason, A.;

    2000-01-01

    Northeast Atlantic, the concentration of wintering animals is around 30% of that in the Norwegian Sea and the vertical distribution is more diffuse and on average deeper. Modelling studies have shown that the overwinter distribution and transport are key factors determining the spatial persistence of C...

  10. CHARACTERIZATION OF WESTERN NORTH ATLANTIC RIGHT WHALE SPRING FEEDING HABITAT

    Science.gov (United States)

    The Great South Channel region of the southwestern Gulf of Maine, between George's Bank and Cape Cod, is the primary spring feeding ground for the western North Atlantic population of the I northern right whale, E. glacialis .Since this whale is so endangered, it is critical to i...

  11. Latitudinal variation in Atlantic Salpa fusiformis Cuvier, 1804 (Tunicata, Thaliacea)

    NARCIS (Netherlands)

    Soest, van R.W.M.

    1972-01-01

    The existence of clinal variation in some morphological characters of Atlantic Salpa fusiformis Cuvier, 1804, is reported. The number of muscle fibres of both aggregate and solitary individuals is subjected to a decrease from higher to lower latitudes. Size and reproduction also seem to vary accordi

  12. Arctic warming will promote Atlantic-Pacific fish interchange

    Science.gov (United States)

    Wisz, M. S.; Broennimann, O.; Grønkjær, P.; Møller, P. R.; Olsen, S. M.; Swingedouw, D.; Hedeholm, R. B.; Nielsen, E. E.; Guisan, A.; Pellissier, L.

    2015-03-01

    Throughout much of the Quaternary Period, inhospitable environmental conditions above the Arctic Circle have been a formidable barrier separating most marine organisms in the North Atlantic from those in the North Pacific. Rapid warming has begun to lift this barrier, potentially facilitating the interchange of marine biota between the two seas. Here, we forecast the potential northward progression of 515 fish species following climate change, and report the rate of potential species interchange between the Atlantic and the Pacific via the Northwest Passage and the Northeast Passage. For this, we projected niche-based models under climate change scenarios and simulated the spread of species through the passages when climatic conditions became suitable. Results reveal a complex range of responses during this century, and accelerated interchange after 2050. By 2100 up to 41 species could enter the Pacific and 44 species could enter the Atlantic, via one or both passages. Consistent with historical and recent biodiversity interchanges, this exchange of fish species may trigger changes for biodiversity and food webs in the North Atlantic and North Pacific, with ecological and economic consequences to ecosystems that at present contribute 39% to global marine fish landings.

  13. President Ilves at the Atlantic Council / Ago Ambre

    Index Scriptorium Estoniae

    Ambre, Ago

    2010-01-01

    President Toomas Hendrik Ilvese esinemisest 19. märtsil 2010 Washingtonis transatlantilisi suhteid arendavas rahvusvahelises välis- ja julgeolekupoliitilises mõttekojas ja poliitikakeskuses Atlantic Council. Kohtumisest Atantic Council'i Ameerika Ühendriikide poolsete juhtidega. Töövisiit Ameerika Ühendriikidesse 17.-23.03.2010

  14. Litter survey detects the South Atlantic 'garbage patch'.

    Science.gov (United States)

    Ryan, Peter G

    2014-02-15

    A distance-based technique was used to assess the distribution and abundance of floating marine debris (>1cm) in the southeast Atlantic Ocean between Cape Town and Tristan da Cunha, crossing the southern edge of the South Atlantic 'garbage patch' predicted by surface drift models. Most litter was made of plastic (97%). Detection distances were influenced by the size and buoyancy of litter items. Litter density decreased from coastal waters off Cape Town (>100 items km(-2)) to oceanic waters (<10 items km(-2)), and was consistently higher (6.2 ± 1.3 items km(-2)) from 3 to 8°E than in adjacent oceanic waters (2.7 ± 0.3 items km(-2)) or in the central South Atlantic around Tristan (1.0 ± 0.4 items km(-2)). The area with high litter density had few seaweeds, suggesting that most litter had been drifting for a long time. The results indicate that floating debris is accumulating in the South Atlantic gyre as far south as 34-35°S. PMID:24360332

  15. 77 FR 70551 - Highly Migratory Species; Atlantic Shark Management Measures

    Science.gov (United States)

    2012-11-26

    ... annual gross revenues from non- blacknose SCS landings would be the same as the status quo in the short... status quo in the short- term. However, this Alternative Suite could have minor negative direct and... Part 635 Highly Migratory Species; Atlantic Shark Management Measures; Proposed Rule...

  16. Trans-Atlantic rafting by the brooding reef coral

    NARCIS (Netherlands)

    Hoeksema, B.W.; Roos, P.J.; Cadée, G.C.

    2012-01-01

    Specimens of the brooding reef coral Favia fragum were found on man-made flotsam stranded on the North Sea shore of the Netherlands. Based on the associated epifauna originating from the southeast USA, we estimate that the corals must have crossed the Atlantic Ocean, transported by the Gulf Stream a

  17. The Kane fracture zone in the Central Atlantic Ocean

    NARCIS (Netherlands)

    Purdy, G.M.; Rabinowitz, P.D.; Velterop, J.J.A.

    1979-01-01

    The Kane fracture zone has been traced as a distinct topographic trough from the Mid-Atlantic Ridge near 24°N to the 80-m.y. B.P. isochron (magnetic anomaly 34) on either side of the ridge axis for a total of approximately 2800 km. Major changes in trend of the fracture zone occur at approximately 7

  18. Atlantic Bluefin Tuna (Thunnus thynnus Biometrics and Condition.

    Directory of Open Access Journals (Sweden)

    Enrique Rodriguez-Marin

    Full Text Available The compiled data for this study represents the first Atlantic and Mediterranean-wide effort to pool all available biometric data for Atlantic bluefin tuna (Thunnus thynnus with the collaboration of many countries and scientific groups. Biometric relationships were based on an extensive sampling (over 140,000 fish sampled, covering most of the fishing areas for this species in the North Atlantic Ocean and Mediterranean Sea. Sensitivity analyses were carried out to evaluate the representativeness of sampling and explore the most adequate procedure to fit the weight-length relationship (WLR. The selected model for the WLRs by stock included standardized data series (common measurement types weighted by the inverse variability. There was little difference between annual stock-specific round weight-straight fork length relationships, with an overall difference of 6% in weight. The predicted weight by month was estimated as an additional component in the exponent of the weight-length function. The analyses of monthly variations of fish condition by stock, maturity state and geographic area reflect annual cycles of spawning and feeding behavior. We update and improve upon the biometric relationships for bluefin currently used by the International Commission for the Conservation of Atlantic Tunas, by incorporating substantially larger datasets than ever previously compiled, providing complete documentation of sources and employing robust statistical fitting. WLRs and other conversion factors estimated in this study differ from the ones used in previous bluefin stock assessments.

  19. 77 FR 61727 - Atlantic Highly Migratory Species; Vessel Monitoring Systems

    Science.gov (United States)

    2012-10-11

    ... rule (76 FR 75492) and type approval notice (76 FR 75523) updating VMS requirements in Atlantic HMS... possessed onboard, and location and timing of landing. These requirements were originally effective March 1... specifying target species, gear possessed onboard, and location and timing of landing. However, no...

  20. Geomagnetic observations on Tristan da Cunha, South Atlantic Ocean

    DEFF Research Database (Denmark)

    Matzka, J.; Olsen, Nils; Maule, C. F.;

    2009-01-01

    Few geomagnetic ground observations exist of the Earth's strongest core field anomaly, the South Atlantic Anomaly (SAA). The geomagnetic repeat station on the island Tristan da Cunha, located half-way between South Africa and South America at 37 degrees 05' S, 12 degrees 18' W, is therefore of cr...

  1. Organic complexation of iron in the West Atlantic Ocean

    NARCIS (Netherlands)

    Gerringa, L.J.A.; Rijkenberg, M.J.; Schoemann, V.; Laan, P.; de Baar, H.J.W.

    2015-01-01

    The characteristics of the dissolved iron (DFe) binding organic ligands were determined during 3 Dutch GEOTRACES cruises covering the length of the West Atlantic Ocean. Adsorptive Differential Pulse Cathodic Stripping Voltammetry (AdDPCSV) with TAC as competing ligand was used to measure Fe binding

  2. 75 FR 13681 - Television Broadcasting Services; Atlantic City, NJ

    Science.gov (United States)

    2010-03-23

    ... COMMISSION 47 CFR Part 73 Television Broadcasting Services; Atlantic City, NJ AGENCY: Federal Communications... amended, to allocate not less than one very high frequency commercial television channel to each State, if... Review Act, see 5 U.S.C. 801(a)(1)(A). List of Subjects in 47 CFR Part 73 Television,...

  3. Forestry serving urban societies in the north atlantic region

    DEFF Research Database (Denmark)

    2010-01-01

    In the North Atlantic Region, the social services provided by forests play a major role. With the high level of urbanisation in many of these countries, forests and other green areas are of great importance as recreational settings for urban dwellers. In order to ensure that forests cater for the...

  4. The Atlantic Meridional Overturning Circulation's Response to Variable Buoyancy Forcing

    Science.gov (United States)

    Butler, Edward; Oliver, Kevin; Hirschi, Joël

    2014-05-01

    The Meridional Overturning Circulation (MOC) is a large-scale global circulation of water (and heat) throughout the world's ocean. It is an integral part of the climate system, responsible for significant anomalous warming of the North Atlantic region. Much of our current understanding of the MOC is based on equilibrium theories. However, the MOC is not a steady circulation and exhibits variability across a broad range of timescales. We examine the transient response of global ocean overturning, with particular emphasis on the Atlantic MOC (AMOC), to periodic variations in the North Atlantic meridional density gradient on decadal, centennial, and millennial timescales within the Nucleus for European Modelling of the Ocean (NEMO) model framework. We use the ORCA2 global ocean configuration of NEMO (with realistic topography and a horizontal resolution of 2°) and impose periodic variations in air temperature over the North Atlantic. In response, we see large oscillations in the strength of the AMOC which peak in magnitude at 128-year timescales. A scaling relationship of the form Ψ ~ ΔρH2 (in which Δρ is a measure of meridional density gradient and H is the depth scale of maximal overturning) is found to hold for the AMOC in these transient simulations with strongest correlations observed at centennial timescales. We explore the validity of this scaling relationship across a broad range of spatial and temporal scales and discuss its validity in a global context.

  5. Global Warming Attenuates the Tropical Atlantic-Pacific Teleconnection.

    Science.gov (United States)

    Jia, Fan; Wu, Lixin; Gan, Bolan; Cai, Wenju

    2016-02-03

    Changes in global sea surface temperature (SST) since the end of last century display a pattern of widespread warming intercepted by cooling in the eastern equatorial Pacific and western coasts of the American continent. Studies have suggested that the cooling in the eastern equatorial Pacific may be partly induced by warming in the North Atlantic. However, it remains unknown how stable this inter-tropical teleconnection will be under global warming. Here we show that the inter-tropical teleconnection from the tropical Atlantic to Pacific weakens substantially as the CO2 concentration increases. This reduced impact is related to the El Niño-like warming of the tropical Pacific mean state, which leads to limited seasonal migration of the Pacific inter-tropical convergence zone (ITCZ) and weakened ocean heat transport. A fast decay of the tropical Atlantic SST anomalies in a warmer climate also contributes to the weakened teleconnection. Our study suggests that as greenhouse warming continues, the trend in the tropical Pacific as well as the development of ENSO will be less frequently interrupted by the Atlantic because of this attenuation. The weakened teleconnection is also supported by CMIP5 models, although only a few of these models can capture this inter-tropical teleconnection.

  6. 76 FR 56742 - Mid-Atlantic Fishery Management Council; Workshop

    Science.gov (United States)

    2011-09-14

    ... to address ecosystem considerations in the fishery management process as well as to examine how... National Oceanic and Atmospheric Administration RIN 0648-XA700 Mid-Atlantic Fishery Management Council... (NOAA), Commerce. ACTION: Notice of a workshop. SUMMARY: The Eight Regional Fishery Management...

  7. Can oceanic paleothermometers reconstruct the Atlantic Multidecadal Oscillation?

    Directory of Open Access Journals (Sweden)

    D. Heslop

    2010-10-01

    Full Text Available Instrumental records of North Atlantic sea surface temperature reveal a large-scale low frequency mode of variability that has become known as the Atlantic Multidecadal Oscillation (AMO. Proxy and modelling studies have demonstrated the important consequences of the AMO on other components of the climate system both within and outside the Atlantic region. Over longer time scales the past behavior of the AMO is predominantly constrained by terrestrial proxies and only a limited number of records are available from the marine realm itself. Here we use an Earth System-Climate Model of intermediate complexity to simulate AMO-type behavior in the Atlantic with a specific focus placed on the ability of ocean paleothermometers to capture the associated surface and subsurface temperature variability. Given their lower prediction errors and annual resolution, coral-based proxies of sea surface temperature appear to be capable of reconstructing the temperature variations associated with the past AMO with an adequate signal-to-noise ratio. Contrastingly, the relatively high prediction error and low temporal resolution of sediment-based proxies, such as the composition of foraminiferal calcite, limits their ability to produce interpretable records of past temperature anomalies corresponding to AMO activity.

  8. Can oceanic paleothermometers reconstruct the Atlantic Multidecadal Oscillation?

    Directory of Open Access Journals (Sweden)

    D. Heslop

    2011-03-01

    Full Text Available Instrumental records of the North Atlantic sea surface temperature reveal a large-scale low frequency mode of variability that has become known as the Atlantic Multidecadal Oscillation (AMO. Proxy and modelling studies have demonstrated the important consequences of the AMO on other components of the climate system both within and outside the Atlantic region. Over longer time scales, the past behavior of the AMO is predominantly constrained by terrestrial proxies and only a limited number of records are available from the marine realm itself. Here we use an Earth System-Climate Model of intermediate complexity to simulate AMO-type behavior in the Atlantic with a specific focus placed on the ability of ocean paleothermometers to capture the associated surface and subsurface temperature variability. Given their lower prediction errors and annual resolution, coral-based proxies of sea surface temperature appear to be capable of reconstructing the temperature variations associated with the past AMO with an adequate signal-to-noise ratio. In contrast, the relatively high prediction error and low temporal resolution of sediment-based proxies, such as the composition of foraminiferal calcite, limits their ability to produce interpretable records of past temperature anomalies corresponding to AMO activity. Whilst the presented results will inevitably be model-dependent to some degree, the statistical framework is model-independent and can be applied to a wide variety of scenarios.

  9. Fishery Management: contrasts in the Mediterranean and the Atlantic

    OpenAIRE

    Smith, M.; Garcia, S.M.

    2014-01-01

    Two recent papers point to differing trends in the status of fish stocks in the Mediterranean and Atlantic fisheries of Europe. We discuss the possible reasons for these contrasting trends in relation to the history, ecosystems, fisheries and management in the two regions.

  10. 77 FR 10772 - Fresh and Chilled Atlantic Salmon From Norway

    Science.gov (United States)

    2012-02-23

    ..., 2011 (76 FR 166) and determined on April 8, 2011 that it would conduct full reviews (76 FR 22422, April..., 2011 (76 FR 38698). The hearing was held in Washington, DC, on November 30, 2011, and all persons who... COMMISSION Fresh and Chilled Atlantic Salmon From Norway Determination On the basis of the record...

  11. Unraveling biocomplexity of Northeast Atlantic herring stocks using SNP markers

    DEFF Research Database (Denmark)

    Bekkevold, Dorte; Limborg, Morten; Helyar, Sarah;

    2012-01-01

    polymorphism (SNP) markers in Northeast Atlantic herring population samples. Marker panels were targeted to include gene‐associated loci to maximize statistical resolution. Application of 281 SNP markers to samples representing different levels of stock complexity showed that the regional origin of individual...

  12. Microbial communities on Australian modified atmosphere packaged Atlantic salmon.

    Science.gov (United States)

    Powell, S M; Tamplin, M L

    2012-05-01

    The role of specific spoilage organisms (SSO) in products such as Atlantic salmon has been well documented. However, little is known about what other micro-organisms are present and these organisms may indirectly influence spoilage by their interactions with the SS0. We used a combination of culture-based and DNA-based methods to explore the microbial communities found on Atlantic salmon fillets packed in a modified atmosphere of carbon dioxide and nitrogen. After 15 days the communities were dominated by Shewanella spp. or Carnobacterium spp. and a variety of other genera were present in smaller numbers. Variability in the microbial community composition in packages processed on the same day was also observed. This was mostly due to differences in the presence of minor members of the community including species from genera such as Iodobacter, Serratia, Morganella and Yersinia. The combination of culture-based and culture-independent methods provided greater insight into the development of microbial communities on Atlantic salmon than would have been possible using only one method. This work highlights the potential importance of lactic acid bacteria (LAB) in fresh Atlantic salmon stored under modified atmosphere conditions.

  13. The spatial distribution and evolution characteristics of North Atlantic cyclones

    Science.gov (United States)

    Dacre, H.; Gray, S.

    2009-09-01

    Mid-latitude cyclones play a large role in determining the day-to-day weather conditions in western Europe through their associated wind and precipitation patterns. Thus, their typical spatial and evolution characteristics are of great interest to meteorologists, insurance and risk management companies. In this study a feature tracking algorithm is applied to a cyclone database produced using the Hewson-method of cyclone identification, based on low-level gradients of wet-bulb potential temperature, to produce a climatology of mid-latitude cyclones. The aim of this work is to compare the cyclone track and density statistics found in this study with previous climatologies and to determine reasons for any differences. This method is found to compare well with other cyclone identification methods; the north Atlantic storm track is reproduced along with the major regions of genesis. Differences are attributed to cyclone lifetime and strength thresholds, dataset resolution and cyclone identification and tracking methods. Previous work on cyclone development has been largely limited to case studies as opposed to analysis of climatological data, and does not distinguish between the different stages of cyclone evolution. The cyclone database used in this study allows cyclone characteristics to be tracked throughout the cyclone lifecycle. This enables the evaluation of the characteristics of cyclone evolution for systems forming in different genesis regions and a calculation of the spatial distribution and evolution of these characteristics in composite cyclones. It was found that most of the cyclones that cross western Europe originate in the east Atlantic where the baroclinicity and sea surface temperature gradients are weak compared to the west Atlantic. East Atlantic cyclones also have higher low-level relative vorticity and lower mean sea level pressure at their genesis point than west Atlantic cyclones. This is consistent with the hypothesis that they are secondary

  14. Extratropical North Atlantic SST influence on Sahel rainfall

    Science.gov (United States)

    Liu, Y.; Chiang, J. C.

    2013-12-01

    We present evidence suggesting that the late 1960's Sahel drought was linked to an abrupt cooling in the extratropical North Atlantic, whose influence was then propagated to the Sahel by atmospheric teleconnection. Such linkages have been observed in paleoclimate during abrupt climate changes of the last glacial period. They have also occurred in coupled model simulations of Atlantic meridional overturning circulation (AMOC) slowdown, the latter being the leading cause of said paleoclimate abrupt changes. The AMOC-slowdown simulations show a characteristic global pattern of climate changes, including a northern hemispheric-wide cooling and increased surface pressure, and weakening of the West African and Asian monsoons. We show that an observed northern-hemispheric pattern of changes, resembling the AMOC slowdown, occurred during the late 1960's, co-incident with the Sahel drought. A combined principal component analysis of 20th century surface temperature, sea level pressure and precipitation extracts a leading mode whose spatial pattern closely resemble the impacts of AMOC slowdown. A similar analysis of AMIP-type simulations forced by 20th century observed forcings shows a similar result, suggesting that the origins of the climate change reside in SST changes, in particular over extratropical North Atlantic. Taken together, the results suggests the influence of extratropical North Atlantic cooling on the 20th century Sahel drought, and a teleconnection pathway through surface/tropospheric cooling. Motivated by our observational result, we investigated atmospheric teleconnection mechanisms of extratropical North Atlantic cooling in an atmospheric general circulation model (GCM) coupled with slab ocean. Our results indicate the central role of tropospheric cooling in communicating the influence on the Sahel. We explicitly show this using regional climate model simulation of the Sahel, with air temperature and associated humidity anomalies from the GCM simulation

  15. Southwest Atlantic water mass evolution during the last deglaciation

    Science.gov (United States)

    Lund, D. C.; Tessin, A. C.; Hoffman, J. L.; Schmittner, A.

    2015-05-01

    The rise in atmospheric CO2 during Heinrich Stadial 1 (HS1; 14.5-17.5 kyr B.P.) may have been driven by the release of carbon from the abyssal ocean. Model simulations suggest that wind-driven upwelling in the Southern Ocean can liberate 13C-depleted carbon from the abyss, causing atmospheric CO2 to increase and the δ13C of CO2 to decrease. One prediction of the Southern Ocean hypothesis is that water mass tracers in the deep South Atlantic should register a circulation response early in the deglaciation. Here we test this idea using a depth transect of 12 cores from the Brazil Margin. We show that records below 2300 m remained 13C-depleted until 15 kyr B.P. or later, indicating that the abyssal South Atlantic was an unlikely source of light carbon to the atmosphere during HS1. Benthic δ18O results are consistent with abyssal South Atlantic isolation until 15 kyr B.P., in contrast to shallower sites. The depth dependent timing of the δ18O signal suggests that correcting δ18O for ice volume is problematic on glacial terminations. New data from 2700 to 3000 m show that the deep SW Atlantic was isotopically distinct from the abyss during HS1. As a result, we find that mid-depth δ13C minima were most likely driven by an abrupt drop in δ13C of northern component water. Low δ13C at the Brazil Margin also coincided with an ~80‰ decrease in Δ14C. Our results are consistent with a weakening of the Atlantic meridional overturning circulation and point toward a northern hemisphere trigger for the initial rise in atmospheric CO2 during HS1.

  16. Trends in the exploitation of South Atlantic shark populations.

    Science.gov (United States)

    Barreto, Rodrigo; Ferretti, Francesco; Flemming, Joanna M; Amorim, Alberto; Andrade, Humber; Worm, Boris; Lessa, Rosangela

    2016-08-01

    Approximately 25% of globally reported shark catches occur in Atlantic pelagic longline fisheries. Strong declines in shark populations have been detected in the North Atlantic, whereas in the South Atlantic the situation is less clear, although fishing effort has been increasing in this region since the late 1970s. We synthesized information on shark catch rates (based on 871,177 sharks caught on 86,492 longline sets) for the major species caught by multiple fleets in the South Atlantic between 1979 and 2011. We complied records from fishing logbooks of fishing companies, fishers, and onboard observers that were supplied to Brazilian institutions. By using exploratory data analysis and literature sources, we identified 3 phases of exploitation in these data (Supporting Information). From 1979 to 1997 (phase A), 5 fleets (40 vessels) fished mainly for tunas. From 1998 to 2008 (phase B), 20 fleets (100 vessels) fished for tunas, swordfishes, and sharks. From 2008 to 2011 (phase C), 3 fleets (30 vessels) fished for multiple species, but restrictive measures were implemented. We used generalized linear models to standardize catch rates and identify trends in each of these phases. Shark catch rates increased from 1979 to 1997, when fishing effort was low, decreased from 1998 to 2008, when fishing effort increased substantially, and remained stable or increased from 2008 to 2011, when fishing effort was again low. Our results indicate that most shark populations affected by longlines in the South Atlantic are currently depleted, but these populations may recover if fishing effort is reduced accordingly. In this context, it is problematic that comprehensive data collection, monitoring, and management of these fisheries ceased after 2012. Concurrently with the fact that Brazil is newly identified by FAO among the largest (and in fastest expansion) shark sub-products consumer market worldwide. PMID:26634410

  17. Trends in the exploitation of South Atlantic shark populations.

    Science.gov (United States)

    Barreto, Rodrigo; Ferretti, Francesco; Flemming, Joanna M; Amorim, Alberto; Andrade, Humber; Worm, Boris; Lessa, Rosangela

    2016-08-01

    Approximately 25% of globally reported shark catches occur in Atlantic pelagic longline fisheries. Strong declines in shark populations have been detected in the North Atlantic, whereas in the South Atlantic the situation is less clear, although fishing effort has been increasing in this region since the late 1970s. We synthesized information on shark catch rates (based on 871,177 sharks caught on 86,492 longline sets) for the major species caught by multiple fleets in the South Atlantic between 1979 and 2011. We complied records from fishing logbooks of fishing companies, fishers, and onboard observers that were supplied to Brazilian institutions. By using exploratory data analysis and literature sources, we identified 3 phases of exploitation in these data (Supporting Information). From 1979 to 1997 (phase A), 5 fleets (40 vessels) fished mainly for tunas. From 1998 to 2008 (phase B), 20 fleets (100 vessels) fished for tunas, swordfishes, and sharks. From 2008 to 2011 (phase C), 3 fleets (30 vessels) fished for multiple species, but restrictive measures were implemented. We used generalized linear models to standardize catch rates and identify trends in each of these phases. Shark catch rates increased from 1979 to 1997, when fishing effort was low, decreased from 1998 to 2008, when fishing effort increased substantially, and remained stable or increased from 2008 to 2011, when fishing effort was again low. Our results indicate that most shark populations affected by longlines in the South Atlantic are currently depleted, but these populations may recover if fishing effort is reduced accordingly. In this context, it is problematic that comprehensive data collection, monitoring, and management of these fisheries ceased after 2012. Concurrently with the fact that Brazil is newly identified by FAO among the largest (and in fastest expansion) shark sub-products consumer market worldwide.

  18. Bathypelagic Food Web Structure of the Northern Atlantic Mid-Atlantic Ridge Based on Stable Isotope Analysis

    Science.gov (United States)

    The objective of our study was to characterize the trophic connections of the dominant fishes of the deep-pelagic region of the northern Mid-Atlantic Ridge (MAR) with respect to vertical distribution using carbon (C) and nitrogen (N) stable isotope analysis. Our goals were to id...

  19. Genetic evidence of local exploitation of Atlantic salmon in a coastal subsistence fishery in the Northwest Atlantic

    Science.gov (United States)

    Bradbury, Ian R.; Hamilton, Lorraine C.; Rafferty, Sara; Meerburg, David; Poole, Rebecca; Dempson, J. Brian; Robertson, Martha J.; Reddin, David G.; Bourret, Vincent; Dionne, Mélanie; Chaput, Gerald J.; Sheehan, Timothy F.; King, Tim L.; Candy, John R.; Bernatchez, Louis

    2014-01-01

    Fisheries targeting mixtures of populations risk the over utilization of minor stock constituents unless harvests are monitored and managed. We evaluated stock composition and exploitation of Atlantic salmon in a subsistence fishery in coastal Labrador, Canada using genetic mixture analysis and individual assignment with a microsatellite baseline (15 loci, 11 829 individuals, 12 regional groups) encompassing the species western Atlantic range. Bayesian and maximum likelihood mixture analyses of fishery samples over six years (2006-2011; 1 772 individuals) indicate contributions of adjacent stocks of 96-97%. Estimates of fishery associated exploitation were highest for Labrador salmon (4.2-10.6% per year) and generally < 1% for other regions. Individual assignment of fishery samples indicated non-local contributions to the fishery (e.g., Quebec, Newfoundland) were rare and primarily in southern Labrador, consistent with migration pathways utilizing the Strait of Belle Isle. This work illustrates how genetic analysis of mixed stock Atlantic salmon fisheries in the northwest Atlantic using this new baseline can disentangle exploitation and reveal complex migratory behaviours.

  20. North Atlantic explosive cyclones and large scale atmospheric variability modes

    Science.gov (United States)

    Liberato, Margarida L. R.

    2015-04-01

    Extreme windstorms are one of the major natural catastrophes in the extratropics, one of the most costly natural hazards in Europe and are responsible for substantial economic damages and even fatalities. During the last decades Europe witnessed major damage from winter storms such as Lothar (December 1999), Kyrill (January 2007), Klaus (January 2009), Xynthia (February 2010), Gong (January 2013) and Stephanie (February 2014) which exhibited uncommon characteristics. In fact, most of these storms crossed the Atlantic in direction of Europe experiencing an explosive development at unusual lower latitudes along the edge of the dominant North Atlantic storm track and reaching Iberia with an uncommon intensity (Liberato et al., 2011; 2013; Liberato 2014). Results show that the explosive cyclogenesis process of most of these storms at such low latitudes is driven by: (i) the southerly displacement of a very strong polar jet stream; and (ii) the presence of an atmospheric river (AR), that is, by a (sub)tropical moisture export over the western and central (sub)tropical Atlantic which converges into the cyclogenesis region and then moves along with the storm towards Iberia. Previous studies have pointed to a link between the North Atlantic Oscillation (NAO) and intense European windstorms. On the other hand, the NAO exerts a decisive control on the average latitudinal location of the jet stream over the North Atlantic basin (Woollings et al. 2010). In this work the link between North Atlantic explosive cyclogenesis, atmospheric rivers and large scale atmospheric variability modes is reviewed and discussed. Liberato MLR (2014) The 19 January 2013 windstorm over the north Atlantic: Large-scale dynamics and impacts on Iberia. Weather and Climate Extremes, 5-6, 16-28. doi: 10.1016/j.wace.2014.06.002 Liberato MRL, Pinto JG, Trigo IF, Trigo RM. (2011) Klaus - an exceptional winter storm over Northern Iberia and Southern France. Weather 66:330-334. doi:10.1002/wea.755 Liberato

  1. Linking The Atlantic Gyres: Warm, Saline Intrusions From Subtropical Atlantic to the Nordic Seas

    Science.gov (United States)

    Hakkinen, Sirpa M.; Rhines, P. B.

    2010-01-01

    Ocean state estimates from SODA assimilation are analyzed to understand how major shifts in the North Atlantic Current path relate to AMOC, and how these shifts are related to large scale ocean circulation and surface forcing. These complement surface-drifter and altimetry data showing the same events. SODA data indicate that the warm water limb of AMOC, reaching to at least 600m depth, expanded in density/salinity space greatly after 1995, and that Similar events occurred in the late 1960s and around 1980. While there were large changes in the upper limb, there was no immediate response in the dense return flow, at least not in SODA, however one would expect a delayed response of increasing AMOC due to the positive feedback from increased salt transport. These upper limb changes are winddriven, involving changes in the eastern subpolar gyre, visible in the subduction of low potential vorticity waters. The subtropical gyre has been weak during the times of the northward intrusions of the highly saline subtropical waters, while the NAO index has been neutral or in a negative phase. The image of subtropical/subpolar gyre exchange through teleconnections within the AMOC overturning cell will be described.

  2. Imaging the lithosphere of rifted passive margins using waveform tomography: North Atlantic, South Atlantic and beyond

    Science.gov (United States)

    Lebedev, Sergei; Schaeffer, Andrew; Celli, Nicolas Luca

    2016-04-01

    Lateral variations in seismic velocities in the upper mantle reflect variations in the temperature of the rocks at depth. Seismic tomography thus provides a proxy for lateral changes in the temperature and thickness of the lithosphere. It can map the deep boundaries between tectonic blocks with different properties and age of the lithosphere. Our 3D tomographic models of the upper mantle and the crust at the Atlantic and global scales are constrained by an unprecedentedly large global dataset of broadband waveform fits (over one million seismograms) and provide improved resolution of the lithosphere, compared to other available models. The most prominent high-velocity anomalies, seen down to 150-200 km depths, indicate the cold, thick, stable mantle lithosphere beneath Precambrian cratons, including those in North America, Greenland, northern and eastern Europe, Africa and South America. The dominant, large-scale, low-velocity feature is the global system of mid-ocean ridges, with broader low-velocity regions near hotspots, including Iceland. Currently active continental rifts show highly variable expression in the upper mantle, from pronounced low velocities to weak anomalies; this correlates with the amount of magmatism within the rift zone. Rifted passive margins have typically undergone cooling since the rifting and show more subtle variations in their seismic-velocity structure. Their thermal structure and evolution, however, are also shaped by 3D geodynamic processes since their formation, including cooling by the adjacent cratonic blocks inland and heating by warm oceanic asthenosphere.

  3. Temperature responses of tropical to warm-temperate Atlantic seaweeds .2. Evidence for ecotypic differentiation in amphi-Atlantic tropical-Mediterranean species

    NARCIS (Netherlands)

    Pakker, H; Breeman, AM

    1996-01-01

    Nineteen isolates of four amphi-Atlantic seaweed species with a tropical to warm-temperate/Mediterranean distribution (Microdictyon boergesenii, M. tenuis, Wurdenmannia miniata and Valonia utricularis) and one eastern Atlantic endemic (M. calodictyon) have been investigated for their temperature res

  4. Atlantic Ocean CARINA data: overview and salinity adjustments

    Directory of Open Access Journals (Sweden)

    T. Tanhua

    2010-02-01

    Full Text Available Water column data of carbon and carbon-relevant hydrographic and hydrochemical parameters from 188 previously non-publicly available cruise data sets in the Arctic Mediterranean Seas, Atlantic and Southern Ocean have been retrieved and merged into a new database: CARINA (CARbon dioxide IN the Atlantic Ocean. The data have gone through rigorous quality control procedures to assure the highest possible quality and consistency. The data for the pertinent parameters in the CARINA database were objectively examined in order to quantify systematic differences in the reported values, i.e. secondary quality control. Systematic biases found in the data have been corrected in the three data products: merged data files with measured, calculated and interpolated data for each of the three CARINA regions, i.e. the Arctic Mediterranean Seas, the Atlantic and the Southern Ocean. These products have been corrected to be internally consistent. Ninety-eight of the cruises in the CARINA database were conducted in the Atlantic Ocean, defined here as the region south of the Greenland-Iceland-Scotland Ridge and north of about 30° S. Here we present an overview of the Atlantic Ocean synthesis of the CARINA data and the adjustments that were applied to the data product. We also report the details of the secondary QC (Quality Control for salinity for this data set. Procedures of quality control – including crossover analysis between stations and inversion analysis of all crossover data – are briefly described. Adjustments to salinity measurements were applied to the data from 10 cruises in the Atlantic Ocean region. Based on our analysis we estimate the internal consistency of the CARINA-ATL salinity data to be 4.1 ppm. With these adjustments the CARINA data products are consistent both internally as well as with GLODAP data, an oceanographic data set based on the World Hydrographic Program in the 1990s, and is now suitable for accurate assessments of, for example

  5. Summer North Atlantic Oscillation and flood variability in Switzerland

    Science.gov (United States)

    Peña, Juan Carlos; Schulte, Lothar; Badoux, Alexandre

    2016-04-01

    The study analyses the possible links between flood frequency in Switzerland and the North Atlantic dynamics over the last two centuries. Given the intricate topography of Switzerland, it will generate a territorial division to retain main physiographic and environmental dissimilarities between different regions. The flood variability in Switzerland over the period 1800-2010 has been determined from a flood damage index for July and August months. The index considers very severe and catastrophic floods from existing flood inventories, summarizing both the severity of these events, their spatial extent and the regional differences. Special attention will be focused on the disparities between flood dynamics at northern and southern slopes of the Alps. The analysis of the possible links between floods and North Atlantic dynamics is focused on the low-frequency atmospheric circulation patterns. Summer climate in the North Atlantic-European sector shows a principal pattern of year-to-year variability, although this pattern is weaker than the North Atlantic Oscillation (NAO) in winter and is confined to northern latitudes. By analogy the climatology community refers to this pattern as the Summer North Atlantic Oscillation (SNAO), which is defined as the main empirical orthogonal function of the standardized anomalies of the European mean sea level pressure during July and August. The flood damage index provides evidences of floods clusters in: 1830-1851, 1881-1927, 1977-1990 and 2005 to present. These clusters coincide with those reported from Switzerland and from some areas of the European continent such as the Czech Republic, Italy and the eastern half of the Iberian Peninsula. This link is not so close when compared with the flood occurrences in Germany. The analysis of the principal mode of low-frequency atmospheric variability shows that the Swiss river catchments situated on the center and southern flank of the Alps are affected by atmospherically unstable areas

  6. South Atlantic intermediate water advances into the North-east Atlantic with reduced Atlantic meridional overturning circulation during the last glacial period

    Science.gov (United States)

    Dubois-Dauphin, Quentin; Bonneau, Lucile; Colin, Christophe; Montero-Serrano, Jean-Carlos; Montagna, Paolo; Blamart, Dominique; Hebbeln, Dierk; Van Rooij, David; Pons-Branchu, Edwige; Hemsing, Freya; Wefing, Anne-Marie; Frank, Norbert

    2016-06-01

    The Nd isotopic composition (ɛNd) of seawater and cold-water coral (CWC) samples from the Gulf of Cádiz and the Alboran Sea, at a depth of 280-827 m were investigated in order to constrain middepth water mass dynamics within the Gulf of Cádiz over the past 40 ka. ɛNd of glacial and Holocene CWC from the Alboran Sea and the northern Gulf of Cádiz reveals relatively constant values (-8.6 to -9.0 and -9.5 to -10.4, respectively). Such values are similar to those of the surrounding present-day middepth waters from the Mediterranean Outflow Water (MOW; ɛNd ˜ -9.4) and Mediterranean Sea Water (MSW; ɛNd ˜ -9.9). In contrast, glacial ɛNd values for CWC collected at thermocline depth (550-827 m) in the southern Gulf of Cádiz display a higher average value (-8.9 ± 0.4) compared to the present-day value (-11.7 ± 0.3). This implies a higher relative contribution of water masses of Mediterranean (MSW) or South Atlantic origin (East Antarctic Intermediate Water, EAAIW). Our study has produced the first evidence of significant radiogenic ɛNd values (˜ -8) at 19, 23-24, and 27 ka, which are coeval with increasing iceberg discharges and a weakening of Atlantic Meridional Overturning Circulation (AMOC). Since MOW ɛNd values remained stable during the last glacial period, it is suggested that these radiogenic ɛNd values most likely reflect an enhanced northward propagation of glacial EAAIW into the eastern Atlantic Basin.

  7. The Atlantic Alliance and the New Strategic Concept

    Directory of Open Access Journals (Sweden)

    Javier Conde

    2000-05-01

    Full Text Available The strategic concept of the Atlantic Alliance has evolved beginning with the incorporation of new countries and the need to respond and adapt to international changes. The author discusses the evolution of this latest concept and describes and analyzes in detail the newstrategic concept approved in April 1999, which is considered both groundbreaking and a demonstration of continuity. Continuity because it reaffirms collective defense as the backbone of the Alliance and groundbreaking because it attempts to contribute, decisively, to security in the broad sense of the Euro-Atlantic area, to the approved enlargement of the organization, to the fostering of good relations with Russia and the Ukraine and to the creation of a European Security and Defense Identity (ESDI. On this last point, Javier Conde explores the difficulties of constructing this identity within the EU’s present framework and reminds the reader howdeterminate the transatlantic link with the United States is for Europeans.

  8. Arctic warming will promote Atlantic-Pacific fish interchange

    DEFF Research Database (Denmark)

    Wisz, Mary; Broennimann, O.; Grønkjær, Peter;

    2015-01-01

    the interchange of marine biota between the two seas. Here, we forecast the potential northward progression of 515 fish species following climate change, and report the rate of potential species interchange between the Atlantic and the Pacific via the Northwest Passage and the Northeast Passage. For this, we...... projected niche-based models under climate change scenarios and simulated the spread of species through the passages when climatic conditions became suitable. Results reveal a complex range of responses during this century, and accelerated interchange after 2050. By 2100 up to 41 species could enter......Throughout much of the Quaternary Period, inhospitable environmental conditions above the Arctic Circle have been a formidable barrier separating most marine organisms in the North Atlantic from those in the North Pacific. Rapid warming has begun to lift this barrier, potentially facilitating...

  9. Deep ocean early warning signals of an Atlantic MOC collapse

    CERN Document Server

    Feng, Qing Yi; Dijkstra, Henk A

    2014-01-01

    The Atlantic Meridional Overturning Circulation (MOC) is a crucial part of the climate system because of its associated northward heat transport. The present-day MOC is sensitive to freshwater anomalies and may collapse to a state with a strongly reduced northward heat transport. A future collapse of the Atlantic MOC has been identified as one of the most dangerous tipping points in the climate system. It is therefore crucial to develop early warning indicators for such a potential collapse based on relatively short time series. So far, attempts to use indicators based on critical slowdown have been marginally successful. Based on complex climate network reconstruction, we here present a promising new indicator for the MOC collapse that efficiently monitors spatial changes in deep ocean circulation. Through our analysis of the performance of this indicator we formulate optimal locations of measurement of the MOC to provide early warning signals of a collapse. Our results imply that an increase in spatial reso...

  10. Changing statistics of storms in the North Atlantic?

    International Nuclear Information System (INIS)

    Problems in the present discussion about increasing storminess in the North Atlantic area are discusesd. Observational data so far available do not indicate a change in the storm statistics. Output from climate models points to an itensified storm track in the North Atlantic, but because of the limited skill of present-day climate models in simulating high-frequency variability and regional details any such 'forecast' has to be considered with caution. A downscaling procedure which relates large-scale time-mean aspects of the state of the atmosphere and ocean to the local statistics of storms is proposed to reconstruct past variations of high-frequency variability in the atmosphere (storminess) and in the sea state (wave statistics). First results are presented. (orig.)

  11. Tropical Pacific influences on the North Atlantic Thermohaline Circulation

    Directory of Open Access Journals (Sweden)

    M. Latif

    2003-06-01

    Full Text Available Most global climate models simulate a weakening of the North Atlantic Thermohaline Circulation (THC in response to enhanced greenhouse warming. Both surface warming and freshening in high latitudes, the so-called sinking region, contribute to the weakening of the THC. Some models simulate even a complete breakdown of the THC at sufficiently strong forcing. Here results from a state-of-the-art global climate model are presented that does not simulate a weakening of the THC in response to greenhouse warming. Large-scale air-sea interactions in the tropics, similar to those operating during present-day El Niños, lead to anomalously high salinities in the tropical Atlantic. These are advected into the sinking region, thereby increasing the surface density and compensating the effects of the local warming and freshening. The results of the model study are corroborated by the analysis of observations.

  12. The South Atlantic in the Fine-Resolution Antarctic Model

    Directory of Open Access Journals (Sweden)

    D. P. Stevens

    Full Text Available The geographical area covered by the Fine-Resolution Antarctic Model (FRAM includes that part of the South Atlantic south of 24°S. A description of the dynamics and thermodynamics of this region of the model is presented. Both the mean and eddy fields in the model are in good agreement with reality, although the magnitude of the transients is somewhat reduced. The heat flux is northward and in broad agreement with many other estimates. Agulhas eddies are formed by the model and propagate westward into the Atlantic providing a mechanism for fluxing heat from the Indian Ocean. The confluence of the Brazil and Falkland currents produces a strong front and a large amount of mesoscale activity. In the less stratified regions to the south, topographic steering of the Antarctic circumpolar current is important.

  13. Solar Influence on the North Atlantic Oscillation - Initial Results

    CERN Document Server

    Dacie, Sally

    2015-01-01

    Some initial investigations into various atmospheric phenomena and the influence of the solar cycle on weather have been made. Strongly negative North Atlantic Oscillation (NAO) indices, which cause cold and dry winter weather in North West Europe, rarely occur during periods of high solar activity. Coupling between the troposphere and stratosphere is discussed, particularly in the context of Polar-night jet oscillation events (defined by Hitchcock et al., 2013) and the Quasi-Biennial Oscillation. The energy of North Atlantic hurricanes (as indicated by the Accumulated Cyclone Energy Index, ACE) is also linked to solar activity, via UV heating at the tropopause (Elsner et al., 2010), and is suggested as a possible mechanism through which solar activity could influence the NAO. Finally the lack of solar influence on the NAO before $\\sim$ 1950 is addressed, with a possible cause being the smaller solar cycle amplitudes. This short report contains several ideas, which may be worth pursuing further.

  14. The arctic mirage and the early north atlantic.

    Science.gov (United States)

    Sawatzky, H L; Lehn, W H

    1976-06-25

    The arctic mirage is a phenomenon that is common in higher latitudes. It occurs under conditions of pronounced temperature inversion, which impart to the air a refractive capability that may equal or exceed the curvature of the earth. Manifestations of the arctic mirage, though largely forgotten in modern times, are described in the earliest accounts of North Atlantic discovery. This interdisciplinary investigation, combining historical induction with scientific observation and analysis, has suggested a new interpretation of historical events. We believe that information gleaned from these mirages was vital to Norse navigation and exploration in the North Atlantic. We further contend that the mirage may furnish a logical basis for the pervasive ancient and medieval concept of the flat or saucer-shaped world. PMID:17739820

  15. Atlantic forcing of persistent drought in West Africa.

    Science.gov (United States)

    Shanahan, T M; Overpeck, J T; Anchukaitis, K J; Beck, J W; Cole, J E; Dettman, D L; Peck, J A; Scholz, C A; King, J W

    2009-04-17

    Although persistent drought in West Africa is well documented from the instrumental record and has been primarily attributed to changing Atlantic sea surface temperatures, little is known about the length, severity, and origin of drought before the 20th century. We combined geomorphic, isotopic, and geochemical evidence from the sediments of Lake Bosumtwi, Ghana, to reconstruct natural variability in the African monsoon over the past three millennia. We find that intervals of severe drought lasting for periods ranging from decades to centuries are characteristic of the monsoon and are linked to natural variations in Atlantic temperatures. Thus the severe drought of recent decades is not anomalous in the context of the past three millennia, indicating that the monsoon is capable of longer and more severe future droughts.

  16. Layered Atlantic Smoke Interactions with Clouds (LASIC) Science Plan

    Energy Technology Data Exchange (ETDEWEB)

    Zuidema, P [University of Miami; Chiu, C [University of Reading; Fairall, CW [NOAA - Environmental Technology Laboratory; Ghan, SJ [Pacific Northwest National Laboratory; Kollias, P [Stony Brook University; McFarguhar, GM; Mechem, DB [University of Kansas; Romps, DM [Lawrence Berkeley National Laboratory; Wong, H; Yuter, SE [North Carolina State University; Alvarado, MJ [Atmospheric and Environmental Research, Inc.; DeSzoeke, SP; Feingold, G [NOAA - Earth System Research Laboratory; Haywood, JM; Lewis, ER [Brookhaven National Laboratory; McComiskey, A [National Oceanic and Atmospheric Administration; Redemann, J [NASA - Ames Research Center; Turner, DD [National Oceanic and Atmospheric Administration; Wood, R [University of Washington; Zhu, P [Florida International University

    2015-12-01

    Southern Africa is the world’s largest emitter of biomass-burning (BB) aerosols. Their westward transport over the remote southeast Atlantic Ocean colocates some of the largest atmospheric loadings of absorbing aerosol with the least examined of the Earth’s major subtropical stratocumulus decks. Global aerosol model results highlight that the largest positive top-of-atmosphere forcing in the world occurs in the southeast Atlantic, but this region exhibits large differences in magnitude and sign between reputable models, in part because of high variability in the underlying model cloud distributions. Many uncertainties contribute to the highly variable model radiation fields: the aging of shortwave-absorbing aerosol during transport, how much of the aerosol mixes into the cloudy boundary layer, and how the low clouds adjust to smoke-radiation and smoke-cloud interactions. In addition, the ability of the BB aerosol to absorb shortwave radiation is known to vary seasonally as the fuel type on land changes.

  17. A seasonal diary of phytoplankton in the North Atlantic

    DEFF Research Database (Denmark)

    Lindemann, Christian; St. John, Michael

    2014-01-01

    In recent years new biological and physical controls have been suggested to drive phytoplankton bloom dynamics in the North Atlantic. A better understanding of the mechanisms driving primary production has potentially important implications for the understanding of the biological carbon pump, as it...... are not mutually exclusive, but rather complementary. Thus, moving beyond the “single mechanism” point of view, here we present an integrated conceptual model of the physical and biological controls on phytoplankton dynamics in the North Atlantic. Further we believe that the acclimation of...... physiological rates can play an important role in mediating phytoplankton dynamics. Thus, this view emphasizes the occurrence of multiple controls and relates their variations in impact to climate change...

  18. Dynamical Attribution of Recent Variability in Atlantic Overturning

    Science.gov (United States)

    Pillar, Helen; Heimbach, Patrick; Johnson, Helen; Marshall, David

    2016-04-01

    Attributing observed variability of the Atlantic Meridional Overturning Circulation (AMOC) to past changes in surface forcing is challenging but essential for detecting any influence of anthropogenic forcing and reducing uncertainty in future climate predictions. Here we obtain quantitative estimates of wind and buoyancy-driven AMOC variations at 25N by projecting observed atmospheric anomalies onto model-based dynamical patterns of AMOC sensitivity to surface wind, thermal and freshwater forcing over the preceding 15 years. We show that local wind forcing dominates AMOC variability on short timescales, whereas subpolar heat fluxes dominate on decadal timescales. The reconstructed transport time series successfully reproduces most of the interannual variability observed by the RAPID-MOCHA array. However, the apparent decadal trend in the RAPID-MOCHA time series is not captured, requiring improved model representation of ocean adjustment to subpolar heat fluxes over at least the past two decades, and highlighting the importance of sustained monitoring of the high latitude North Atlantic.

  19. Evaporation duct occurrences in the northeast Atlantic during late summer

    OpenAIRE

    Callahan, Thomas Edwin

    1980-01-01

    Approved for public release; distribution is unlimited Analyses and interpretation of surface layer and synoptic-scale data obtained in the Northwest Atlantic were performed to obtain descriptions of the evaporation duct and associated atmospheric and oceanic synoptic features. The surface layer data were quite unique because they were obtained from high quality measurements from ships spatially separated in a fixed array. Magnitudes and horizontal homogeneity of duct heights were compar...

  20. Marine zooplanktonic diversity: a view from the South Atlantic

    OpenAIRE

    Boltovskoy, D.; Correa, N.; Boltovskoy, A.

    2002-01-01

    Approximately 7000 marine zooplanktonic species have been described so far for the World Ocean; in the South Atlantic the presence of 40% of these has been confirmed, and an additional 20-30% are expected to be recorded in the future. The overall number of described species is very low when compared with other communities, and yet it may not be too far from the final, complete inventory. Very ample geographic distributional ranges, compositional similarity between the major oceanic basins, an...

  1. The Atlantic Alliance and Geopolitics: New Realities and New Challenges

    OpenAIRE

    Lie, Kai Olaf

    2009-01-01

    This paper is based on the hypothesis that the new geopolitical environment for the Atlantic Alliance is mainly influenced by the following five elements: The renaissance of Germany as the central player on the European theater after the collapse of the Soviet Union; the shift of American geopolitical focus from Europe to the Middle East and central Asia; the increasing geopolitical influence of petroleum energy resources; the increasing power of china; and the differing perceptions of politi...

  2. Ozone in the Atlantic Ocean marine boundary layer

    OpenAIRE

    Patrick Boylan; Detlev Helmig; Samuel Oltmans

    2015-01-01

    Abstract In situ atmospheric ozone measurements aboard the R/V Ronald H. Brown during the 2008 Gas-Ex and AMMA research cruises were compared with data from four island and coastal Global Atmospheric Watch stations in the Atlantic Ocean to examine ozone transport in the marine boundary layer (MBL). Ozone measurements made at Tudor Hill, Bermuda, were subjected to continental outflow from the east coast of the United States, which resulted in elevated ozone levels above 50 ppbv. Ozone measurem...

  3. Isotope analysis reveals foraging area dichotomy for atlantic leatherback turtles.

    Directory of Open Access Journals (Sweden)

    Stéphane Caut

    Full Text Available BACKGROUND: The leatherback turtle (Dermochelys coriacea has undergone a dramatic decline over the last 25 years, and this is believed to be primarily the result of mortality associated with fisheries bycatch followed by egg and nesting female harvest. Atlantic leatherback turtles undertake long migrations across ocean basins from subtropical and tropical nesting beaches to productive frontal areas. Migration between two nesting seasons can last 2 or 3 years, a time period termed the remigration interval (RI. Recent satellite transmitter data revealed that Atlantic leatherbacks follow two major dispersion patterns after nesting season, through the North Gulf Stream area or more eastward across the North Equatorial Current. However, information on the whole RI is lacking, precluding the accurate identification of feeding areas where conservation measures may need to be applied. METHODOLOGY/PRINCIPAL FINDINGS: Using stable isotopes as dietary tracers we determined the characteristics of feeding grounds of leatherback females nesting in French Guiana. During migration, 3-year RI females differed from 2-year RI females in their isotope values, implying differences in their choice of feeding habitats (offshore vs. more coastal and foraging latitude (North Atlantic vs. West African coasts, respectively. Egg-yolk and blood isotope values are correlated in nesting females, indicating that egg analysis is a useful tool for assessing isotope values in these turtles, including adults when not available. CONCLUSIONS/SIGNIFICANCE: Our results complement previous data on turtle movements during the first year following the nesting season, integrating the diet consumed during the year before nesting. We suggest that the French Guiana leatherback population segregates into two distinct isotopic groupings, and highlight the urgent need to determine the feeding habitats of the turtle in the Atlantic in order to protect this species from incidental take by

  4. Edge effect on vascular epiphytes in a subtropical Atlantic Forest

    OpenAIRE

    Juliana Santos Bianchi; Rodrigo de Andrade Kersten

    2014-01-01

    Forest fragmentation affects biological communities by reducing habitat and increasing edges, thus reducing the effective size of the habitable zones. The subtropical atlantic Araucaria forest, typical on the southern Brazil, in some regions has been reduced to less than 1% of its original size lasting only in small isolated fragments. This study aimed to analyse the impact the edge has on vascular epiphyte ensemble in a remnant of Araucaria forest. We surveyed 40 host trees in four transects...

  5. Eddy length scales in the North Atlantic Ocean

    OpenAIRE

    Eden, Carsten

    2007-01-01

    Eddy length scales are calculated from satellite altimeter products and in an eddy-resolving model of the North Atlantic Ocean. Four different measures for eddy length scales are derived from kinetic energy densities in wave number space and spatial decorrelation scales. Observational estimates and model simulation agree well in all these measures near the surface. As found in previous studies, all length scales are, in general, decreasing with latitude. They are isotropic and proportional to...

  6. Excess post hypoxic oxygen consumption in Atlantic cod (Gadus morhua)

    DEFF Research Database (Denmark)

    Plambech, M.; Deurs, Mikael van; Steffensen, J.F.;

    2013-01-01

    Atlantic cod Gadus morhua experienced oxygen deficit (DO2 ) when exposed to oxygen levels below their critical level (c. 73% of pcrit) and subsequent excess post-hypoxic oxygen consumption (CEPHO) upon return to normoxic conditions, indicative of an oxygen debt. The mean±s.e. CEPHO:DO2 was 6·9±1·......·9±1·5, suggesting that resorting to anaerobic energy production in severe hypoxia is energetically expensive...

  7. Wave Height Distribution Observed by Ships in the North Atlantic

    DEFF Research Database (Denmark)

    Olsen, Anders Smærup; Schrøter, Carsten; Jensen, Jørgen Juncher

    2005-01-01

    The analysis of almost 25000 observation of the wave height from ships in the North Atlantic shows that the encountered wave height distribution is significantly lower than the distribution provided by the classification societies for structural assessment. The joint probability distribution for ...... that the ship will maintain the service speed even in relatively severe sea. The distribution derived could be used to incorporate the effect of weather routing in a long term analysis of the wave loads on a ship....

  8. Seasonality of mercury in the Atlantic marine boundary layer

    Science.gov (United States)

    Soerensen, Anne L.; Sunderland, Elsie; Skov, Henrik; Holmes, Christopher; Jacob, Daniel J.

    2010-05-01

    Around one third of the mercury emissions today are from primary anthropogenic sources, with the remaining two-thirds from secondary reemissions of earlier deposition and natural sources (AMAP/UNEP 2008). Mercury exchange at the air-sea interface is important for the global distribution of atmospheric mercury as parts of deposited mercury will reenter the atmosphere through evasion. The exchange at the air-sea interface also affects the amount of inorganic mercury in the ocean and thereby the conversion to the neuro-toxic methylmercury. Here we combine new cruise measurements in the atmospheric marine boundary layer (MBL) of the Atlantic Ocean (Northern Hemisphere) from the fall of 2006 and the spring of 2007 with existing data from cruises in the Atlantic Ocean since 1978. We observe from these data a seasonal cycle in Hg(0) concentrations in the Atlantic marine boundary later (MBL) that exhibits minimum concentrations during summer and high concentrations during fall to spring. These observations suggest a local, seasonally dependent Hg(0) source in the MBL that causes variability in concentrations above the open ocean. To further investigate controls on Hg(0) concentrations in the MBL, we developed an improved representation of oceanic air-sea exchange processes within the GEOS-Chem global 3-D biogeochemical mercury model. Specifically, we used new data on mercury redox reactions in the surface ocean as a function of biological and photochemical processes, and implemented new algorithms for mercury dynamics associated with suspended particles. Our coupled atmospheric-oceanic modeling results support the premise that oceanic evasion is a main driver controlling Hg(0) concentrations in the MBL. We also use the model to investigate what drivers the evasion across the air-sea interface on shorter timescales. This is done by tracking evasion rates and other model components on an hourly basis for chosen locations in the Atlantic Ocean.

  9. Biocomplexity in a highly migratory pelagic marine fish, Atlantic herring

    OpenAIRE

    Ruzzante, Daniel E.; Mariani, Stefano; Bekkevold, Dorte; André, Carl; Mosegaard, Henrik; Clausen, Lotte A.W; Thomas G Dahlgren; Hutchinson, William F.; HATFIELD Emma M. C.; Torstensen, Else; Brigham, Jennifer; Simmonds, E. John; Laikre, Linda; Larsson, Lena C; Stet, René J.M

    2006-01-01

    The existence of biologically differentiated populations has been credited with a major role in conferring sustainability and in buffering overall productivity of anadromous fish population complexes where evidence for spatial structure is uncontroversial. Here, we describe evidence of correlated genetic and life history (spawning season linked to spawning location) differentiation in an abundant and highly migratory pelagic fish, Atlantic herring, Clupea harengus, in the North Sea (NS) and a...

  10. Geographical distribution of pelagic decapod shrimp in the Atlantic Ocean.

    Science.gov (United States)

    Judkins, David C

    2014-01-01

    Ninety-one species of pelagic decapod shrimp were identified in 938 midwater-trawl collections taken between 1963 and 1974 from the North and South Atlantic. Distributional maps are provided for the most frequently occurring species. Nighttime abundance of most species was greatest within the upper 200 m. Degree of geographical overlap was estimated using the geometric mean of the proportion of joint occurrences with a value ≥ 0.5 deemed significant. Geographical distributions tended to be unique, and only 31 species had values ≥ 0.5 with one or more other species. Species within genera and within phylogenetic subgroups of Sergia were generally parapatric or partially overlapping in distribution. Five geographical groupings of co-occurring species across genera were identified: Subpolar-Temperate, Southern Hemisphere, Central, Tropical, Eastern Tropical and Western Tropical. The two species of the Southern Hemisphere group are circumpolar at temperate latitudes. The 12 species of the Central group occurred throughout the subtropical and tropical North and South Atlantic. The eight species of the Tropical group occurred broadly across the equatorial Atlantic and Caribbean with ranges usually extending into the Gulf of Mexico and northward in the Gulf Stream. The two species of the Western Tropical group occurred most often in the western tropics, but there were scattered occurrences at subtropical latitudes. The four species of the Eastern Tropical group were endemic to the Mauritanian Upwelling and the Angola-Benguela Frontal zones off western Africa. Two of the three species in the Subpolar-Temperate group had bipolar distributions, and all three occurred in the Mediterranean and in the Mauritanian Upwelling zone. Most Central, Tropical and Western Tropical species were present in the in the Gulf of Mexico. The 10 species from the Mediterranean were a mixture of Subpolar-Temperate, Central and benthopelagic species. Patterns of distribution in Atlantic pelagic

  11. Changing waves and storms in the Northeast Atlantic?

    Energy Technology Data Exchange (ETDEWEB)

    Carretero, J.C.; Gomez, M.; Lozano, I. [Programa de Clima Maritimo (Puertos del Estado), Madrid (Spain)] [and others; WASA group

    1997-12-31

    The European project WASA has been set up to verifying, or to disprove hypotheses of a worsening storm and wave climate in the Northeast Atlantic and its adjacent seas in the present century. Its main conclusion is that the storm- and wave climate in most of the Northeast Atlantic and in the North Sea has undergone significant variations on time scales of decades; it has indeed roughened in recent decades, but the present intensity of the storm- and wave-climate seems to be comparable with that at the beginning of this century. Part of this variability is found to be related to the North Atlantic oscillation. An analysis of a high-resolution climate change experiment, mimicking global warming due to increased greenhouse gas concentrations, results in a weak increase of storm activity and (extreme) wave heights in the Bay of Biscay and in the North Sea, while storm action and waves slightly decrease along the Norwegian coast and in most of the remaining North Atlantic area. A weak increase in storm surges in the southern and eastern part of the North Sea is expected. These projected anthropogenic changes at the time of CO{sub 2} doubling fall well within the limits of variability observed in the past. A major methodical obstacle for the assessment of changes in the intensity of storm and wave events are inhomogeneities in the observational record, both in terms of local observations and of analyzed pro ducts (such as weather maps), which usually produce an artificial increase of extreme winds. This occurs because older analyses were based on fewer observations and with more limited conceptual and numerical models of the dynamical processes than more recent analyses. 52 refs.

  12. Canopy gap colonization in the Atlantic Montane Rain Forest

    OpenAIRE

    Renato A. Ferreira de Lima; Leila Cunha de Moura

    2006-01-01

    In the Atlantic Montane Rain Forest of South-eastern Brazil, a study was carried out to describe and evaluate canopy gap colonization. Gap composition by herb species was assessed through their soil coverage and woody species by measuring and identifying all individuals taller than one meter. Gap structure (gap size, number and diameter of treefalls), topographic position and surrounding vegetation were also measured. Two genera of Marantaceae were markedly frequent and abundant inside gaps. ...

  13. The Atlantic salmon genome provides insights into rediploidization

    OpenAIRE

    Lien, Sigbjorn; Koop, Ben F; Sandve, Simen R.; Miller, Jason R.; Kent, Matthew P.; Nome, Torfinn; Hvidsten, Torgeir R.; Leong, Jong S; Minkley, David R; Zimin, Aleksey; Grammes, Fabian; Grove, Harald; Gjuvsland, Arne; Walenz, Brian; Hermansen, Russell A.

    2016-01-01

    The whole-genome duplication 80 million years ago of the common ancestor of salmonids (salmonid-specific fourth vertebrate whole-genome duplication, Ss4R) provides unique opportunities to learn about the evolutionary fate of a duplicated vertebrate genome in 70 extant lineages. Here we present a high-quality genome assembly for Atlantic salmon (Salmo salar), and show that large genomic reorganizations, coinciding with bursts of transposon-mediated repeat expansions, were crucial for the post-...

  14. The Indian Ocean Dipole's influence on Atlantic tropical cyclone activity

    Science.gov (United States)

    Marinaro, Alan Joseph

    Improving early tropical cyclone forecasts would assist reinsurance decision makers as they seek information that can minimize risks. Early lead forecasts are based on model variables before December 1 (Year 0) that predict Atlantic tropical cyclone activity (Year +1). The autumn Indian Ocean Dipole (IOD) has an 8 to 14 month antecedent correlation with the El Nino - Southern Oscillation (ENSO). ENSO is traditionally the best non-lead and overall predictor of Atlantic tropical cyclone activity. Analyses were performed over a 30-year period from 1984/85-2013/14, with some time variation depending on the test. Correlation, spatial, and wavelet analyses were utilized to find associations between the IOD, west and east components of the IOD, and four other variables related to the following season's ENSO state and tropical cyclone activity. The prior western pole of the October IOD (WIOD) was demonstrated to have statistically significant r-squared values (i.e. 99% confidence interval) to upcoming tropical storm activity (i.e. explained 25% of the variance), named storm counts (28%), and ENSO (21%). The WIOD has no connection with U.S. hurricane landfalls. Wavelet analysis between October IOD variables and following August-October ENSO data was observed to have the best time-frequency relationship. Dynamic reasoning for these relationships reside within the idealized biennial IOD-ENSO cycle, Walker circulation process, and the impact of ENSO on the state of the Atlantic Basin. The WIOD's integration into early-lead forecast models could be an advantage for those in the reinsurance industry and other decision makers impacted by Atlantic tropical cyclonesn.

  15. Invasive Lionfish Drive Atlantic Coral Reef Fish Declines

    OpenAIRE

    Green, Stephanie J.; John L Akins; Aleksandra Maljković; Isabelle M. Côté

    2012-01-01

    Indo-Pacific lionfish (Pterois volitans and P. miles) have spread swiftly across the Western Atlantic, producing a marine predator invasion of unparalleled speed and magnitude. There is growing concern that lionfish will affect the structure and function of invaded marine ecosystems, however detrimental impacts on natural communities have yet to be measured. Here we document the response of native fish communities to predation by lionfish populations on nine coral reefs off New Providence Isl...

  16. Polar vortex controls coupling of North Atlantic Ocean and atmosphere

    OpenAIRE

    Graf, H; Walter, K.

    2005-01-01

    The structure of the North Atlantic leading atmospheric winter variability mode strongly depends on the state of the polar stratospheric vortex. If the polar vortex is strong, one teleconnection pattern emerges in the upper troposphere, while two mostly independent ones appear when the vortex is weak. The anomaly patterns associated with the different polarities of these modes show strong differences in the wind fields and in the correlation of atmospheric variability with the sea surface tem...

  17. The Atlantic Return and the Payback of Evangelization

    Directory of Open Access Journals (Sweden)

    Valentina Napolitano

    2013-08-01

    Full Text Available This article explores Catholic, transnational Latin American migration to Rome as a gendered and ethnicized Atlantic Return, which is figured as a source of ‘new blood’ that fortifies the Catholic Church but which also profoundly unsettles it. I analyze this Atlantic Return as an angle on the affective force of history in critical relation to two main sources: Diego Von Vacano’s reading of the work of Bartolomeo de las Casas, a 16th-century Spanish Dominican friar; and to Nelson Maldonado-Torres’ notion of the ‘coloniality of being’ which he suggests has operated in Atlantic relations as enduring and present forms of racial de-humanization. In his view this latter can be counterbalanced by embracing an economy of the gift understood as gendered. However, I argue that in the light of a contemporary payback of evangelization related to the original ‘gift of faith’ to the Americas, this economy of the gift is less liberatory than Maldonado-Torres imagines, and instead part of a polyfaceted reproduction of a postsecular neoliberal affective, and gendered labour regime.

  18. Toxaphene in minke whales (Balaenoptera acutorostrata) from the North Atlantic

    International Nuclear Information System (INIS)

    Toxaphene contamination of minke whales (Balaenoptera acutorostrata) from North Atlantic waters was examined for the first time. Total toxaphene and ΣCHB (sum of 11 chlorobornanes) concentrations in blubber samples ranged from 170 ± 110 and 41 ± 39 ng/g lipid weight (l.w.) for female minke whales from southeastern Greenland to 5800 ± 4100 and 1100 ± 780 ng/g l.w. for males from the North Sea, respectively. Very large variations in toxaphene concentrations among sampling areas were observed suggesting a spatial segregation of minke whales. However, much of the apparent geographical discrimination was explained by the seasonal fluctuation of animal fat mass. Patterns of CHBs in males revealed that recalcitrant CHBs were in higher proportions in animals from the more easterly areas than in animals from the more westerly areas. This trend may be influenced by the predominance of the US, over the European, input of toxaphene to North Atlantic waters. - High levels of toxaphene were found in different sub-populations of minke whales from North Atlantic waters

  19. The Cretaceous opening of the South Atlantic Ocean

    Science.gov (United States)

    Granot, Roi; Dyment, Jérôme

    2015-03-01

    The separation of South America from Africa during the Cretaceous is poorly understood due to the long period of stable polarity of the geomagnetic field, the Cretaceous Normal Superchron (CNS, lasted between ∼121 and 83.6 Myr ago). We present a new identification of magnetic anomalies located within the southern South Atlantic magnetic quiet zones that have arisen due to past variations in the strength of the dipolar geomagnetic field. Using these anomalies, together with fracture zone locations, we calculate the first set of magnetic anomalies-based finite rotation parameters for South America and Africa during that period. The kinematic solutions are generally consistent with fracture zone traces and magnetic anomalies outside the area used to construct them. The rotations indicate that seafloor spreading rates increased steadily throughout most of the Cretaceous and decreased sharply at around 80 Myr ago. A change in plate motion took place in the middle of the superchron, roughly 100 Myr ago, around the time of the final breakup (i.e., separation of continental-oceanic boundary in the Equatorial Atlantic). Prominent misfit between the calculated synthetic flowlines (older than Anomaly Q1) and the fracture zones straddling the African Plate in the central South Atlantic could only be explained by a combination of seafloor asymmetry and internal dextral motion (leading to the emergence of north-south flow of intermediate and deep-water which might have triggered the global cooling of bottom water and the end for the Cretaceous greenhouse period.

  20. Aerosol interactions with African/Atlantic climate dynamics

    Science.gov (United States)

    Hosseinpour, F.; Wilcox, E. M.

    2014-07-01

    Mechanistic relationships exist between variability of dust in the oceanic Saharan air layer (OSAL) and transient changes in the dynamics of Western Africa and the tropical Atlantic Ocean. This study provides evidence of possible interactions between dust in the OSAL region and African easterly jet-African easterly wave (AEJ-AEW) system in the climatology of boreal summer, when easterly wave activity peaks. Synoptic-scale changes in instability and precipitation in the African/Atlantic intertropical convergence zone are correlated with enhanced aerosol optical depth (AOD) in the OSAL region in response to anomalous 3D overturning circulations and upstream/downstream thermal anomalies at above and below the mean-AEJ level. Upstream and downstream anomalies are referred to the daily thermal/dynamical changes over the West African monsoon region and the Eastern Atlantic Ocean, respectively. Our hypothesis is that AOD in the OSAL is positively correlated with the downstream AEWs and negatively correlated with the upstream waves from climatological perspective. The similarity between the 3D pattern of thermal/dynamical anomalies correlated with dust outbreaks and those of AEWs provides a mechanism for dust radiative heating in the atmosphere to reinforce AEW activity. We proposed that the interactions of OSAL dust with regional climate mainly occur through coupling of dust with the AEWs.

  1. Invasive lionfish drive Atlantic coral reef fish declines.

    Directory of Open Access Journals (Sweden)

    Stephanie J Green

    Full Text Available Indo-Pacific lionfish (Pterois volitans and P. miles have spread swiftly across the Western Atlantic, producing a marine predator invasion of unparalleled speed and magnitude. There is growing concern that lionfish will affect the structure and function of invaded marine ecosystems, however detrimental impacts on natural communities have yet to be measured. Here we document the response of native fish communities to predation by lionfish populations on nine coral reefs off New Providence Island, Bahamas. We assessed lionfish diet through stomach contents analysis, and quantified changes in fish biomass through visual surveys of lionfish and native fishes at the sites over time. Lionfish abundance increased rapidly between 2004 and 2010, by which time lionfish comprised nearly 40% of the total predator biomass in the system. The increase in lionfish abundance coincided with a 65% decline in the biomass of the lionfish's 42 Atlantic prey fishes in just two years. Without prompt action to control increasing lionfish populations, similar effects across the region may have long-term negative implications for the structure of Atlantic marine communities, as well as the societies and economies that depend on them.

  2. Genomic characterization of the Atlantic cod sex-locus.

    Science.gov (United States)

    Star, Bastiaan; Tørresen, Ole K; Nederbragt, Alexander J; Jakobsen, Kjetill S; Pampoulie, Christophe; Jentoft, Sissel

    2016-01-01

    A variety of sex determination mechanisms can be observed in evolutionary divergent teleosts. Sex determination is genetic in Atlantic cod (Gadus morhua), however the genomic location or size of its sex-locus is unknown. Here, we characterize the sex-locus of Atlantic cod using whole genome sequence (WGS) data of 227 wild-caught specimens. Analyzing more than 55 million polymorphic loci, we identify 166 loci that are associated with sex. These loci are located in six distinct regions on five different linkage groups (LG) in the genome. The largest of these regions, an approximately 55 Kb region on LG11, contains the majority of genotypes that segregate closely according to a XX-XY system. Genotypes in this region can be used genetically determine sex, whereas those in the other regions are inconsistently sex-linked. The identified region on LG11 and its surrounding genes have no clear sequence homology with genes or regulatory elements associated with sex-determination or differentiation in other species. The functionality of this sex-locus therefore remains unknown. The WGS strategy used here proved adequate for detecting the small regions associated with sex in this species. Our results highlight the evolutionary flexibility in genomic architecture underlying teleost sex-determination and allow practical applications to genetically sex Atlantic cod. PMID:27499266

  3. Vulnerability map to erosion of the Uruguayan atlantic coast

    International Nuclear Information System (INIS)

    Full text: The Atlantic Ocean washes about 233 km of coastline in Uruguay from Punta del Este to Barra del Chuy, covering the entire coast of Rocha Department and part of the Department of Maldonado. In this coastal area can be seen a set of landforms that indicate the action of erosion processes that are acting from the highest Quaternary. Mainly highlights the extensive sectors gully nestled on the coastal plain adjoining the strip of beaches , platforms and secondarily the coastal cliffs of more or less active measuring height between these landforms. Approximately 32% of the Atlantic coast (about 74 km) is subjected to the erosive action, especially during times of storms by wind and storm waves . It should also be mentioned that have been estimated at about 86 km2 occupied by mobile dunes area, of which the majority shows evidence of the deflationary action (blow out). With this contribution is to illustrate the distribution of the areas of the Atlantic coast have these landforms of erosion

  4. Seabirds of the Atlantic Frontier, north and west of Scotland

    Science.gov (United States)

    Reid, James B.; Pollock, Claire M.; Mavor, Roddy

    2001-05-01

    The marine environment of the Atlantic Frontier region north and west of Scotland, the focus of recent oil exploration, hosts internationally important concentrations of seabirds. Twenty-three species breed in colonies on the coasts and islands that rise from these waters and a further 25 species use them for feeding at various times of the year. The importance of these populations are set in an international context and their composition and occurrence in the deep waters of the Atlantic Frontier and adjacent continental shelf waters, as revealed by 20 years of at-sea surveys, is described. Deep waters are especially important for procellariiformes whereas shelf waters are important for all species, and overall seabird diversity is greater in shelf waters. The effects of oil pollution on seabirds can be severe, and although the effect of pollution in deep, oceanic waters might be minimal, prevailing currents and winds might result in greater impacts on more westerly, shelf waters. While the perceived threats from oil exploration in the Atlantic Frontier might be small the important seabird assemblage in the region should be considered in future exploitation of hydrocarbons here.

  5. North Atlantic-Fennoscandian Holocene climate trends and mechanisms

    Science.gov (United States)

    Sejrup, Hans Petter; Seppä, Heikki; McKay, Nicholas P.; Kaufman, Darrell S.; Geirsdóttir, Áslaug; de Vernal, Anne; Renssen, Hans; Husum, Katrine; Jennings, Anne; Andrews, John T.

    2016-09-01

    To investigate the mechanisms behind Holocene regional climate trends from north of 58°N in the North Atlantic-Fennoscandian region Principal Component Analysis (PCA) was performed and a temperature anomaly stack produced from 81 proxy derived summer temperature time series from 74 sites. The PC results show distinctly different trends for near-surface versus surface temperatures, demonstrating the importance of handling these separately. The first PC of weighted sea surface summer temperature time series and continental time series explains 45 ± 8% of the variance, where the uncertainty is the standard deviation of the distribution of variance explained across the 1000 age-uncertain ensemble members. PC1 has a relatively uniform expression over the whole region, closely following the summer insolation at 65°N. The second PC explains 22 ± 4% of the variance and shows a non-uniform expression, with loadings in opposite directions in the northern and southeastern parts of the region. Comparing the PC time series with model runs and with the timing of the demise of the Laurentide Ice Sheet (LIS), suggest that this pattern reflects both topographic and albedo effects of the LIS as well as release of meltwater into the North Atlantic and Arctic Oceans. Comparing the stack of gridded records with published global stacks reveals an unusual Holocene temperature development in the North Atlantic-Fennoscandian region most likely resulting from the location relative to the decaying LIS.

  6. Invasive lionfish drive Atlantic coral reef fish declines.

    Science.gov (United States)

    Green, Stephanie J; Akins, John L; Maljković, Aleksandra; Côté, Isabelle M

    2012-01-01

    Indo-Pacific lionfish (Pterois volitans and P. miles) have spread swiftly across the Western Atlantic, producing a marine predator invasion of unparalleled speed and magnitude. There is growing concern that lionfish will affect the structure and function of invaded marine ecosystems, however detrimental impacts on natural communities have yet to be measured. Here we document the response of native fish communities to predation by lionfish populations on nine coral reefs off New Providence Island, Bahamas. We assessed lionfish diet through stomach contents analysis, and quantified changes in fish biomass through visual surveys of lionfish and native fishes at the sites over time. Lionfish abundance increased rapidly between 2004 and 2010, by which time lionfish comprised nearly 40% of the total predator biomass in the system. The increase in lionfish abundance coincided with a 65% decline in the biomass of the lionfish's 42 Atlantic prey fishes in just two years. Without prompt action to control increasing lionfish populations, similar effects across the region may have long-term negative implications for the structure of Atlantic marine communities, as well as the societies and economies that depend on them. PMID:22412895

  7. Aerosol interactions with African/Atlantic climate dynamics

    International Nuclear Information System (INIS)

    Mechanistic relationships exist between variability of dust in the oceanic Saharan air layer (OSAL) and transient changes in the dynamics of Western Africa and the tropical Atlantic Ocean. This study provides evidence of possible interactions between dust in the OSAL region and African easterly jet–African easterly wave (AEJ–AEW) system in the climatology of boreal summer, when easterly wave activity peaks. Synoptic-scale changes in instability and precipitation in the African/Atlantic intertropical convergence zone are correlated with enhanced aerosol optical depth (AOD) in the OSAL region in response to anomalous 3D overturning circulations and upstream/downstream thermal anomalies at above and below the mean-AEJ level. Upstream and downstream anomalies are referred to the daily thermal/dynamical changes over the West African monsoon region and the Eastern Atlantic Ocean, respectively. Our hypothesis is that AOD in the OSAL is positively correlated with the downstream AEWs and negatively correlated with the upstream waves from climatological perspective. The similarity between the 3D pattern of thermal/dynamical anomalies correlated with dust outbreaks and those of AEWs provides a mechanism for dust radiative heating in the atmosphere to reinforce AEW activity. We proposed that the interactions of OSAL dust with regional climate mainly occur through coupling of dust with the AEWs. (paper)

  8. Projected Atlantic hurricane surge threat from rising temperatures.

    Science.gov (United States)

    Grinsted, Aslak; Moore, John C; Jevrejeva, Svetlana

    2013-04-01

    Detection and attribution of past changes in cyclone activity are hampered by biased cyclone records due to changes in observational capabilities. Here, we relate a homogeneous record of Atlantic tropical cyclone activity based on storm surge statistics from tide gauges to changes in global temperature patterns. We examine 10 competing hypotheses using nonstationary generalized extreme value analysis with different predictors (North Atlantic Oscillation, Southern Oscillation, Pacific Decadal Oscillation, Sahel rainfall, Quasi-Biennial Oscillation, radiative forcing, Main Development Region temperatures and its anomaly, global temperatures, and gridded temperatures). We find that gridded temperatures, Main Development Region, and global average temperature explain the observations best. The most extreme events are especially sensitive to temperature changes, and we estimate a doubling of Katrina magnitude events associated with the warming over the 20th century. The increased risk depends on the spatial distribution of the temperature rise with highest sensitivity from tropical Atlantic, Central America, and the Indian Ocean. Statistically downscaling 21st century warming patterns from six climate models results in a twofold to sevenfold increase in the frequency of Katrina magnitude events for a 1 °C rise in global temperature (using BNU-ESM, BCC-CSM-1.1, CanESM2, HadGEM2-ES, INM-CM4, and NorESM1-M). PMID:23509254

  9. The effects of temperature and hatchery-rearing conditions on juvenile Atlantic cod (Gadus morhua) behavior

    OpenAIRE

    Theodorou, Panagiotis, 1983-

    2010-01-01

    Atlantic cod (Gadus morhua) is a demersal gadoid that has been one of the most important species in the North Atlantic fisheries for more than 500 years, with major economic, ecological and cultural significance. However, in the past few decades many of the cod stocks have declined dramatically, because of overfishing and changes in the physical environment with major reorganizations of cod ecosystems. Early in their first year of life Atlantic cod juveniles undergo a transition from pela...

  10. Disease resistance is related to inherent swimming performance in Atlantic salmon

    OpenAIRE

    Castro Vicente; Grisdale-Helland Barbara; Jørgensen Sven M; Helgerud Jan; Claireaux Guy; Farrell Anthony P; Krasnov Aleksei; Helland Ståle J; Takle Harald

    2013-01-01

    Abstract Background Like humans, fish can be classified according to their athletic performance. Sustained exercise training of fish can improve growth and physical capacity, and recent results have documented improved disease resistance in exercised Atlantic salmon. In this study we investigated the effects of inherent swimming performance and exercise training on disease resistance in Atlantic salmon. Atlantic salmon were first classified as either poor or good according to their swimming p...

  11. 46 CFR 7.25 - Montauk Point, NY to Atlantic Beach, NY.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Montauk Point, NY to Atlantic Beach, NY. 7.25 Section 7... LINES Atlantic Coast § 7.25 Montauk Point, NY to Atlantic Beach, NY. (a) A line drawn from Shinnecock... Light 348° true to the southernmost extremity of the spit of land at the western end of Oak Beach. (d)...

  12. On the Inconsistent Relationship between Pacific and Atlantic Niños

    OpenAIRE

    Lübbecke, Joke F.; McPhaden, Michael

    2012-01-01

    The tropical Atlantic wind response to El Niño forcing is robust, with weakened northeast trade winds north of the equator and strengthened southeast trade winds along and south of the equator. However, the relationship between sea surface temperature (SST) anomalies in the eastern equatorial Pacific and Atlantic is inconsistent, with El Niño events followed sometimes by warm and other times by cold boreal summer anomalies in the Atlantic cold tongue region. Using observational data and a hin...

  13. Mechanisms Determining the Winter Atmospheric Response to the Atlantic Overturning Circulation

    OpenAIRE

    Gastineau, Guillaume; L’Hévéder, B.; Codron, Francis; Frankignoul, Claude

    2016-01-01

    International audience In climate models, an intensification of the Atlantic meridional overturning circulation (AMOC) precedes a warming in the North Atlantic subpolar basin by a few years. In the IPSL-CM5A-LR model, this warming may explain the atmospheric response to the AMOC observed in winter, which resembles a negative phase of the North Atlantic Oscillation (NAO). To firmly establish the causality links between the ocean and the atmosphere and illustrate the underlying mechanisms in...

  14. On the configurations of the Atlantic Niño phenomenon under negative AMO phases

    Science.gov (United States)

    Martin-Rey, Marta; Rodríguez de Fonseca, Belen; Polo, Irene; Losada, Teresa; Lazar, Alban

    2016-04-01

    An air-sea coupled mode of inter-annual variability akin to ENSO emerges in the tropical Atlantic basin, named as Atlantic Niño. The teleconnections of the Atlantic Niño phenomenon have changed during recent decades, coinciding with an alteration of its spatial configuration. Previous studies have suggested that the background state could favour particular atmospheric forcings and could also contribute to generate different variability modes. Here, we demonstrate that two different Atlantic Niño patterns coexist in the tropical Atlantic basin during certain decades, coinciding with a negative phase of the Atlantic Multidecadal Oscillation (AMO). The leading mode, Basin-Wide (BW) Atlantic Niño, is characterized by positive SST anomalies covering the entire tropical Atlantic and the second mode, Dipolar (D) Atlantic Niño, presents an equatorial warming flanked by negative SST anomalies in north and south Tropical Atlantic. These modes are driven by different wind patterns, controlled by the Subtropical High Pressure Systems. The BW-Atlantic Niño is preceded by a weakening of both Azores and Sta Helena High, which induces a general reduction of the tropical trades and anomalous wind convergence in the equatorial band. On the other hand, the D-Atlantic Niño is associated with a strengthening of Azores High and a weakening of Sta Helena High, given rise to a meridional Sea Level Pressure (SLP) gradient that intensifies the subtropical trades and generate anomalous trans-equatorial winds along the equatorial band. Both modes seem to be forced by an ENSO-like signal emanating from the Pacific, but with different atmospheric response over the Atlantic. It could be attributed to the changes in the mean state during negative AMO phases. For these decades, shallower thermocline conditions, together with an increase of the oceanic variability (SST and thermocline) in the tropical Atlantic could contribute to the generation of both Atlantic Niño modes. Furthermore, a

  15. Abstracts of the Atlantic Geoscience Society's 2007 colloquium and annual general meeting

    International Nuclear Information System (INIS)

    The Atlantic Geoscience Society (AGS) hosts annual meetings, workshops and field trips to promote a better understanding of the geology of Atlantic Canada. This colloquium highlighted current research in the Atlantic provinces with special sessions devoted to patterns and geohazards in the North Atlantic; late and post-glacial climate change events in eastern Canada; salt matters; tectonic, thermal and resource aspects of Paleozoic to Mesozoic evaporite basins; mineral resources research by students of the Society of Economic Geologists; dendrochronology; a physical volcanology workshop; and, a North American soil geochemical landscape project orientation session. One of the 74 papers presented at this colloquium has been catalogued separately for inclusion in this database

  16. Abstracts of the Atlantic Geoscience Society's 2007 colloquium and annual general meeting

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, S.; Parkhill, M.; Wilson, R.; Desrosiers, M.; Lentz, D.; Pitre, C.; Pronk, T.; Spooner, I.; Toole, R.; Wallace, P. (comps.)

    2007-07-01

    The Atlantic Geoscience Society (AGS) hosts annual meetings, workshops and field trips to promote a better understanding of the geology of Atlantic Canada. This colloquium highlighted current research in the Atlantic provinces with special sessions devoted to patterns and geohazards in the North Atlantic; late and post-glacial climate change events in eastern Canada; salt matters; tectonic, thermal and resource aspects of Paleozoic to Mesozoic evaporite basins; mineral resources research by students of the Society of Economic Geologists; dendrochronology; a physical volcanology workshop; and, a North American soil geochemical landscape project orientation session. One of the 74 papers presented at this colloquium has been catalogued separately for inclusion in this database.

  17. 77 FR 69426 - Fisheries of the Northeastern United States; Atlantic Mackerel, Squid, and Butterfish Fisheries...

    Science.gov (United States)

    2012-11-19

    ... available from: Dr. Christopher M. Moore, Executive Director, Mid-Atlantic Fishery Management Council, Suite... Part 648 Fisheries, Fishing, Recordkeeping and reporting requirements. Dated: November 14, 2012. Alan...

  18. Tropical Pacific/Atlantic Ocean interactions at multi‐decadal time scales

    OpenAIRE

    Latif, Mojib

    2001-01-01

    Analysis of sea surface temperature (SST) observations suggests a pan‐oceanic interaction between the tropical Pacific and the Atlantic Ocean at multi‐decadal time scales, such that periods of anomalously high SSTs in the tropical Pacific are followed by a basin‐wide SST dipole in the Atlantic Ocean with a time delay of a few decades. The SST anomaly structure in the Atlantic Ocean is reminscent of variations in the North Atlantic thermohaline circulation. The two ocean basins are linked thro...

  19. Intensified impact of tropical Atlantic SST on the western North Pacific summer climate under a weakened Atlantic thermohaline circulation

    OpenAIRE

    Chen, Wei; Lee, June-Yi; Lu, Riyu; Dong, Buwen; Ha, Kyung-Ja

    2015-01-01

    The tropical North Atlantic (TNA) sea surface temperature (SST) has been identified as one of regulators on the boreal summer climate over the western North Pacific (WNP), in addition to SSTs in the tropical Pacific and Indian Oceans. The major physical process proposed is that the TNA warming induces a pair of cyclonic circulation anomaly over the eastern Pacific and negative precipitation anomalies over the eastern to central tropical Pacific, which in turn lead to an anticyclonic circulati...

  20. South Atlantic circulation in a world ocean model

    Directory of Open Access Journals (Sweden)

    Matthew H. England

    Full Text Available The circulation in the South Atlantic Ocean has been simulated within a global ocean general circulation model. Preliminary analysis of the modelled ocean circulation in the region indicates a rather close agreement of the simulated upper ocean flows with conventional notions of the large-scale geostrophic currents in the region. The modelled South Atlantic Ocean witnesses the return flow and export of North Atlantic Deep Water (NADW at its northern boundary, the inflow of a rather barotropic Antarctic Circumpolar Current (ACC through the Drake Passage, and the inflow of warm saline Agulhas water around the Cape of Good Hope. The Agulhas leakage amounts to 8.7 Sv, within recent estimates of the mass transport shed westward at the Agulhas retroflection. Topographic steering of the ACC dominates the structure of flow in the circumpolar ocean. The Benguela Current is seen to be fed by a mixture of saline Indian Ocean water (originating from the Agulhas Current and fresher Subantarctic surface water (originating in the ACC. The Benguela Current is seen to modify its flow and fate with depth; near the surface it flows north-westwards bifurcating most of its transport northward into the North Atlantic Ocean (for ultimate replacement of North Atlantic surface waters lost to the NADW conveyor. Deeper in the water column, more of the Benguela Current is destined to return with the Brazil Current, though northward flows are still generated where the Benguela Current extension encounters the coast of South America. At intermediate levels, these northward currents trace the flow of Antarctic Intermediate Water (AAIW equatorward, though even more AAIW is seen to recirculate poleward in the subtropical gyre. In spite of the model's rather coarse resolution, some subtle features of the Brazil-Malvinas Confluence are simulated rather well, including the latitude at which the two currents meet. Conceptual diagrams of the recirculation and interocean

  1. Genomic organization and evolution of the Atlantic salmon hemoglobin repertoire

    Directory of Open Access Journals (Sweden)

    Phillips Ruth B

    2010-10-01

    Full Text Available Abstract Background The genomes of salmonids are considered pseudo-tetraploid undergoing reversion to a stable diploid state. Given the genome duplication and extensive biological data available for salmonids, they are excellent model organisms for studying comparative genomics, evolutionary processes, fates of duplicated genes and the genetic and physiological processes associated with complex behavioral phenotypes. The evolution of the tetrapod hemoglobin genes is well studied; however, little is known about the genomic organization and evolution of teleost hemoglobin genes, particularly those of salmonids. The Atlantic salmon serves as a representative salmonid species for genomics studies. Given the well documented role of hemoglobin in adaptation to varied environmental conditions as well as its use as a model protein for evolutionary analyses, an understanding of the genomic structure and organization of the Atlantic salmon α and β hemoglobin genes is of great interest. Results We identified four bacterial artificial chromosomes (BACs comprising two hemoglobin gene clusters spanning the entire α and β hemoglobin gene repertoire of the Atlantic salmon genome. Their chromosomal locations were established using fluorescence in situ hybridization (FISH analysis and linkage mapping, demonstrating that the two clusters are located on separate chromosomes. The BACs were sequenced and assembled into scaffolds, which were annotated for putatively functional and pseudogenized hemoglobin-like genes. This revealed that the tail-to-tail organization and alternating pattern of the α and β hemoglobin genes are well conserved in both clusters, as well as that the Atlantic salmon genome houses substantially more hemoglobin genes, including non-Bohr β globin genes, than the genomes of other teleosts that have been sequenced. Conclusions We suggest that the most parsimonious evolutionary path leading to the present organization of the Atlantic salmon

  2. Tracking 2012 Atlantic Hurricanes Using NASA's GEOS-5 AGCM

    Science.gov (United States)

    Cordero-Fuentes, M.; Partyka, G. S.; Smith, E. B.

    2014-12-01

    On average, the Atlantic Hurricane Season consists of 11 named storms, including six hurricanes. However, the 2012 hurricane season tied with the 1887, 1995, 2010, and 2011 seasons for having the third-most named storms on record, with 19 named storms, 10 of which were hurricanes. Seven of these systems made landfall in North America, including Hurricane Isaac and "Super-Storm" Sandy. This active season also included Hurricane Nadine, the fourth longest-lived Atlantic hurricane on record. The structure and life cycle of these severe storms can be viewed through the detailed meteorological analyses and forecasts that the Global Modeling and Assimilation Office (GMAO) conducts on a routine basis with our GEOS-5 Atmospheric General Circulation Model (AGCM) system. GMAO routinely produces five-day forecasts twice daily, at 0000 and 1200 UTC, using the GEOS-5 AGCM. The GEOS-5 atmospheric data assimilation system is used to generate near real-time analyses of the atmosphere over the globe every six hours. These analyses provide the initial conditions for the GEOS-5 forecasts. Following the abnormally active 2012 Atlantic hurricane season, one focus has been on the skill of the GEOS-5 forecasts of tropical storms in the Atlantic, East Pacific, and West Pacific. In this presentation it's shown the results for two of the most destructive storms of the Atlantic season: Hurricanes Isaac and Sandy, and the 2012 Season's Track Forecast Error. The primary impetus for investigating these two storms was the opportunity to test the ability of the model to reproduce their track and intensity forecast. We observe several features associated with the morphology and inner core of these storms indicative of the capability of the model to reproduce these tropical systems. GEOS-5 predicted Sandy's intensity to within a few hectopascals over much of the life of the storm. The model also predicted some of the finer details of Sandy's evolution. The forecast from 12z 26Oct2012 appeared to

  3. Intensified impact of tropical Atlantic SST on the western North Pacific summer climate under a weakened Atlantic thermohaline circulation

    Science.gov (United States)

    Chen, Wei; Lee, June-Yi; Lu, Riyu; Dong, Buwen; Ha, Kyung-Ja

    2015-10-01

    The tropical North Atlantic (TNA) sea surface temperature (SST) has been identified as one of regulators on the boreal summer climate over the western North Pacific (WNP), in addition to SSTs in the tropical Pacific and Indian Oceans. The major physical process proposed is that the TNA warming induces a pair of cyclonic circulation anomaly over the eastern Pacific and negative precipitation anomalies over the eastern to central tropical Pacific, which in turn lead to an anticyclonic circulation anomaly over the western to central North Pacific. This study further demonstrates that the modulation of the TNA warming to the WNP summer climate anomaly tends to be intensified under background of the weakened Atlantic thermohaline circulation (THC) by using a water-hosing experiment. The results suggest that the weakened THC induces a decrease in thermocline depth over the TNA region, resulting in the enhanced sensitivity of SST variability to wind anomalies and thus intensification of the interannual variation of TNA SST. Under the weakened THC, the atmospheric responses to the TNA warming are westward shifted, enhancing the anticyclonic circulation and negative precipitation anomaly over the WNP. This study supports the recent finding that the negative phase of the Atlantic multidecadal oscillation after the late 1960s has been favourable for the strengthening of the connection between TNA SST variability and WNP summer climate and has important implications for seasonal prediction and future projection of the WNP summer climate.

  4. Palaeo-oceanographical implications of Early-Middle Miocene subtropical ostracod faunas from the continental shelf of the SE Atlantic Ocean

    DEFF Research Database (Denmark)

    Dingle, R.V.; McMillan, I.K.; Majoram, Stefan;

    2001-01-01

    palaeo-oceanography, miocene, SE Atlantic, ostracoda, upwelling, Benguela current, Agullas current......palaeo-oceanography, miocene, SE Atlantic, ostracoda, upwelling, Benguela current, Agullas current...

  5. Physical and underway data collected aboard the KNORR during cruise KN197-04 in the North Atlantic Ocean and South Atlantic Ocean from 2010-02-19 to 2010-03-12 (NODC Accession 0104286)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0104286 includes physical and underway data collected aboard the KNORR during cruise KN197-04 in the North Atlantic Ocean and South Atlantic Ocean...

  6. Profile and bottle data collected on the RV Melville (cruise Vancouver 06) from the Agulhas-South Atlantic Thermohaline Transport Experiment (ASTTEX) in the Atlantic Ocean from 20030102 to 20030115 (NODC Accession 0074001)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Introduction: The Agulhas-South Atlantic Thermohaline Experiment (ASTTEX) examined the fluxes of heat, salt and mass entering the South Atlantic ocean via the...

  7. Weight loss and fillet quality characteristics of Atlantic salmon (Salmo salar) after purging for 5, 10, 15 or 20 days

    Science.gov (United States)

    Atlantic salmon, Salmo salar, are typically cultured in marine net pens. However, technological advancements in recirculating aquaculture systems have increased the feasibility of culturing Atlantic salmon in land-based systems to alleviate environmental and disease issues limiting sustainability. ...

  8. 76 FR 41764 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Coral and Coral Reefs off the...

    Science.gov (United States)

    2011-07-15

    ... Atlantic; Coral and Coral Reefs off the Southern Atlantic States; Exempted Fishing Permit AGENCY: National... artificial reefs without additional authorization. A report on the project findings is due at the end of...

  9. Identifying the European fossil fuel plumes in the atmosphere over the Northeast Atlantic Region through isotopic observations and numerical modelling

    DEFF Research Database (Denmark)

    Geels, C.; Christensen, J.H.; Hansen, A.W.;

    2006-01-01

    Atmospheric transport, C-14. fossil fuel CO_2, numerical modeling, the north East Atlantic Region Udgivelsesdato: 18 August......Atmospheric transport, C-14. fossil fuel CO_2, numerical modeling, the north East Atlantic Region Udgivelsesdato: 18 August...

  10. Glacial climate sensitivity to different states of the Atlantic Meridional overturning circulation : results from the IPSL model

    OpenAIRE

    Kageyama, M.; J. Mignot; D. Swingedouw; Marzin, C.; Alkama, R.; O. Marti

    2009-01-01

    Numerous records from the North Atlantic and the surrounding continents have shown rapid and large amplitude climate variability during the last glacial period. This variability has often been associated to changes in the Atlantic Meridional Overturning Circulation (AMOC). Rapid climate change on the same time scales has also been reconstructed for sites far away from the North Atlantic, such as the tropical Atlantic, the East Pacific and Asia. The mechanisms explaining these climatic respons...

  11. 77 FR 59593 - Mid-Atlantic Fishery Management Council (MAFMC); Public Meetings

    Science.gov (United States)

    2012-09-28

    ... Fishery Management Council (Council), its Visioning and Strategic Planning Working Group, and Spiny... National Oceanic and Atmospheric Administration RIN 0648-XC260 Mid-Atlantic Fishery Management Council...) 571-4000. Council address: Mid-Atlantic Fishery Management Council, 800 N. State St., Suite 201,...

  12. 76 FR 66041 - Mid-Atlantic Fishery Management Council (MAFMC); Public Meeting

    Science.gov (United States)

    2011-10-25

    ... Fishery Management Council's (Council) Ecosystem and Ocean Planning Committee will hold a public meeting... National Oceanic and Atmospheric Administration RIN 0648-XA786 Mid-Atlantic Fishery Management Council... telephone: (410) 859- 3300. Council address: Mid-Atlantic Fishery Management Council, 800 N. State...

  13. 77 FR 65364 - Mid-Atlantic Fishery Management Council (MAFMC); Public Meeting

    Science.gov (United States)

    2012-10-26

    ... Fishery Management Council (Council) Staff will convene a meeting of the Visioning and Strategic Planning... National Oceanic and Atmospheric Administration RIN 0648-XC316 Mid-Atlantic Fishery Management Council..., Baltimore, MD 21240; telephone: (410) 859-3300. Council address: Mid-Atlantic Fishery Management...

  14. 48 CFR 225.871 - North Atlantic Treaty Organization (NATO) cooperative projects.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false North Atlantic Treaty Organization (NATO) cooperative projects. 225.871 Section 225.871 Federal Acquisition Regulations System... Other International Agreements and Coordination 225.871 North Atlantic Treaty Organization...

  15. Recent increases in Arctic freshwater flux affects Labrador Sea convection and Atlantic overturning circulation

    NARCIS (Netherlands)

    Yang, Qian; Dixon, Timothy H.; Myers, Paul G.; Bonin, Jennifer; Chambers, Don; Van Den Broeke, M. R.

    2016-01-01

    The Atlantic Meridional Overturning Circulation (AMOC) is an important component of ocean thermohaline circulation. Melting of Greenland's ice sheet is freshening the North Atlantic; however, whether the augmented freshwater flux is disrupting the AMOC is unclear. Dense Labrador Sea Water (LSW), for

  16. 77 FR 50019 - Safety Zone; Cocoa Beach Air Show, Atlantic Ocean, Cocoa Beach, FL

    Science.gov (United States)

    2012-08-20

    ...) 366-9826. SUPPLEMENTARY INFORMATION: Table of Acronyms DHS Department of Homeland Security FR Federal... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Cocoa Beach Air Show, Atlantic Ocean, Cocoa... establishing a temporary safety zone on the waters of the Atlantic Ocean located east of Cocoa Beach,...

  17. Atlantic coastal plain geothermal test holes, New Jersey. Hole completion reports

    Energy Technology Data Exchange (ETDEWEB)

    Cobb, L.B.; Radford, L.; Glascock, M.

    1979-03-01

    A description of the Atlantic Coastal Plains Geothermal Drilling Program and data for the following Geothermal test holes drilled in New Jersey are summarized: Site No. 40, Fort Monmouth; Site No. 41, Sea Girt; Site No. 39-A, Forked River; Site No. 38, Atlantic City; and Site No. 36, Cape May.

  18. 77 FR 5560 - Commercial Wind Lease Issuance and Site Assessment Activities on the Atlantic Outer Continental...

    Science.gov (United States)

    2012-02-03

    ... activities (geophysical, geotechnical, archaeological, and biological surveys needed to develop specific... identified these WEAs in a Notice of Intent (NOI) to prepare an EA for Mid-Atlantic WEAs (76 FR 7226). The... published in the Federal Register a NOA of a draft of the EA for Mid-Atlantic WEAs (76 FR 40925)....

  19. 33 CFR 165.T01-0542 - Safety Zones: Neptune Deepwater Port, Atlantic Ocean, Boston, MA.

    Science.gov (United States)

    2010-07-01

    ... Port, Atlantic Ocean, Boston, MA. 165.T01-0542 Section 165.T01-0542 Navigation and Navigable Waters... Guard District § 165.T01-0542 Safety Zones: Neptune Deepwater Port, Atlantic Ocean, Boston, MA. (a) Location. The following areas are safety zones: All navigable waters of the United States within a...

  20. 78 FR 35217 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; American Lobster Fishery

    Science.gov (United States)

    2013-06-12

    ... National Oceanic and Atmospheric Administration 50 CFR Part 697 RIN 0648-AT31 Atlantic Coastal Fisheries Cooperative Management Act Provisions; American Lobster Fishery AGENCY: National Marine Fisheries Service... measures in the Exclusive Economic Zone (EEZ) under the authority of section 803(b) of the Atlantic...

  1. 77 FR 77036 - Mid-Atlantic Fishery Management Council; Public Meeting

    Science.gov (United States)

    2012-12-31

    ... National Oceanic and Atmospheric Administration RIN 0648-XC421 Mid-Atlantic Fishery Management Council... Administration (NOAA), Commerce. ACTION: Notice of a public meeting. SUMMARY: The Mid-Atlantic Fishery Management... options for improving the management of the longfin and Illex squid fisheries, with a focus on...

  2. Indian-atlantic transfer of thermocline water at the agulhas retroflection.

    Science.gov (United States)

    Gordon, A L

    1985-03-01

    During November and December 1983, two anticyclonic eddies were observed west of the Agulhas Retroflection, apparently spawned at the retroflection. The western eddy, centered 300 kilometers southwest of Cape Town, has a winter cooled core encircled by warm Indian Ocean water. Between Cape Town and the "Cape Town Eddy" is a net geostrophic transport of Indian Ocean thermocline water (14 x 10(6) cubic meters per second) into the South Atlantic Ocean. This circulation configuration, similar to that observed by earlier researchers, suggests that Indian-Atlantic thermocline exchange is a common occurrence. Such a warmwater link between the Atlantic and Indian oceans would strongly influence global climate patterns. The Indian Ocean water is warmer than the adjacent South Atlantic water and thus represents a heat input of 2.3 x 10(13) to 47 x 10(13) watts into the Atlantic. The large uncertainty arises from the unknown partition between two possible routes for the return flow from the Atlantic to the Indian Ocean: cooler South Atlantic thermocline water or much colder North Atlantic Deep Water. In either case, interocean mass and heat exchange of thermocline water at the Agulhas Retroflection is a distinct likelihood.

  3. Saline Indian Ocean waters invaded the South Atlantic thermocline during glacial termination II

    NARCIS (Netherlands)

    Scussolini, P.; Scussolini, G.; Brummer, G.-J.A.; Peeters, F.J.C.

    2015-01-01

    Salty and warm Indian Ocean waters enter the South Atlantic via the Agulhas leakage, south of Africa. Model simulations and proxy evidence of Agulhas leakage strengthening during glacial terminations led to the hypothesis that it was an important modulator of the Atlantic Ocean circulation. Yet, the

  4. Timing of migratory baleen whales at the Azores in relation to the North Atlantic spring bloom

    NARCIS (Netherlands)

    F. Visser; K.L. Hartman; G.J. Pierce; V.D. Valavanis; J. Huisman

    2011-01-01

    Each year, a phytoplankton spring bloom starts just north of the North Atlantic Subtropical Gyre, and then expands northwards across the entire North Atlantic. Here, we investigate whether the timing of the spring migration of baleen whales is related to the timing of the phytoplankton spring bloom,

  5. Response of the Asian Summer Monsoon to Weakening of Atlantic Thermohaline Circulation

    Institute of Scientific and Technical Information of China (English)

    Lu Riyu; Buwen DONG

    2008-01-01

    Various paleocllimate records have shown that the Asian monsoon was punctuated by numerous sub-orbital time-scale events,,and these events were coeval with those that happened in the North Atlantic..This study investigates the Asian summer monsoon responses to the Atlantic 0cean forcing by applying an additional freshwater flux into the North Atlantic.The simulated results indicate that the cold North Atlantic and warm South Atlantic induced by the weakened Atlantic thermohaline circulation(THC)due to the freshwater flux lead to significantly suppressed Asian summer monsoon.The authors analyzed the detailed processes of the Atlantic Ocean forcing on the Asian summer monsoon,and found that the atmospheric teleconnection in the eastern and central North Pacific and the atmosphere-ocean interaction in the tropical North Pacific play the most crucial role.Enhanced precipitation in the subtropical North Pacific extends the effects of Atlantic Ocean forcing from the eastern Pacific into the western Pacific,and the atmosphere-ocean jinteraction in the tropical Pacific and Indian 0pcean intensifies the circulation and precipitation anomalies in the Pacific and East Asia.

  6. On the Atlantic cold tongue mode and the role of the Pacific ENSO

    Directory of Open Access Journals (Sweden)

    R. A. F. De Almeida

    2012-01-01

    Full Text Available The dominant mode of coupled ocean-atmosphere variability in the Tropical Atlantic is analysed in this work from a melange of datasets, focusing on the seasonal development and evolution of the Bjerknes feedback responsible for the generation of the Atlantic cold tongue mode. The strength, seasonality and interannual variability of this mode is investigated through a joint EOF analysis of the anomalies of zonal wind velocity in the western basin together with sea surface temperature from the easternmost Tropical Atlantic, and analysed in conjunction with the depth of the 20 °C isotherm, representing the three mechanisms responsible for the generation of the Bjerknes feedback. Results from the EOF analyses confirm the robustness and seasonality of the Atlantic cold tongue mode, with a positive feedback phase peaking during boreal summer when the Bjerknes feedback is stronger. Analysis of an event in 2005 shows that the positive feedback is followed by a negative feedback phase triggered by the wind field and driven by oceanic heat advection. More importantly, we investigated the linearized impact of Niño events in the Pacific Ocean over the Atlantic by projecting the NINO 3.4 index over the Atlantic data. The Atlantic cold tongue mode has its variance reduced from 62% to 47% in the projected dataset, revealing that the Pacific ENSO has an inhibiting effect over its Atlantic counterpart.

  7. 76 FR 54703 - Safety Zone; Myrtle Beach Triathlon, Atlantic Intracoastal Waterway, Myrtle Beach, SC

    Science.gov (United States)

    2011-09-02

    ... Triathlon, Atlantic Intracoastal Waterway, Myrtle Beach, SC in the Federal Register (76 FR 124). We received... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Myrtle Beach Triathlon, Atlantic Intracoastal Waterway, Myrtle Beach, SC AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY:...

  8. 78 FR 35596 - Special Local Regulation; Long Beach Regatta, Powerboat Race, Atlantic Ocean, Long Beach, NY

    Science.gov (United States)

    2013-06-13

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation; Long Beach Regatta, Powerboat Race, Atlantic Ocean, Long Beach, NY AGENCY: Coast Guard, DHS. ACTION: Notice of Proposed Rulemaking... Atlantic Ocean off Long Beach, NY during the Long Beach Regatta Powerboat Race scheduled for August...

  9. 78 FR 56151 - Safety Zone, North Atlantic Ocean; Virginia Beach, VA

    Science.gov (United States)

    2013-09-12

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone, North Atlantic Ocean; Virginia Beach, VA... zone on the navigable waters of the North Atlantic Ocean in Virginia Beach, VA to support the Virginia... Acronyms DHS Department of Homeland Security FR Federal Register NPRM Notice of Proposed Rulemaking...

  10. 75 FR 20550 - Fisheries of the Northeastern United States; Atlantic Herring Fishery; Specifications

    Science.gov (United States)

    2010-04-20

    ... National Oceanic and Atmospheric Administration 50 CFR Part 648 RIN 0648-AY14 Fisheries of the Northeastern United States; Atlantic Herring Fishery; Specifications AGENCY: National Marine Fisheries Service (NMFS... comments. SUMMARY: NMFS proposes 2010-2012 specifications for the Atlantic herring (herring) fishery....

  11. 75 FR 10217 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2010-03-05

    ... business listed under the shark dealer permit which first receives Atlantic sharks (71 FR 58057; October 2... certificate in order to renew either permit (71 FR 58057; October 2, 2006). These certificate(s) are valid for... National Oceanic and Atmospheric Administration RIN 0648-XU40 Schedules for Atlantic Shark...

  12. 76 FR 34209 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2011-06-13

    ... which first receives Atlantic sharks (71 FR 58057; October 2, 2006). Dealers who attend and successfully... permit (71 FR 58057; October 2, 2006). These certificate(s) are valid for 3 years. As such, vessel owners... National Oceanic and Atmospheric Administration RIN 0648-XA450 Schedules for Atlantic Shark...

  13. 78 FR 54456 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2013-09-04

    ... which first receives Atlantic sharks (71 FR 58057; October 2, 2006). Dealers who attend and successfully... to renew either permit (71 FR 58057; October 2, 2006). These certificate(s) are valid for 3 years. As... National Oceanic and Atmospheric Administration RIN 0648-XC810 Schedules for Atlantic Shark...

  14. 76 FR 77214 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2011-12-12

    ... business listed under the shark dealer permit which first receives Atlantic sharks (71 FR 58057; October 2... certificate in order to renew either permit (71 FR 58057; October 2, 2006). These certificate(s) are valid for... National Oceanic and Atmospheric Administration RIN 0648-XA843 Schedules for Atlantic Shark...

  15. 78 FR 15709 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2013-03-12

    ... each business listed under the shark dealer permit which first receives Atlantic sharks (71 FR 58057... certificate in order to renew either permit (71 FR 58057; October 2, 2006). These certificate(s) are valid for... National Oceanic and Atmospheric Administration RIN 0648-XC512 Schedules for Atlantic Shark...

  16. 78 FR 34349 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2013-06-07

    ... which first receives Atlantic sharks (71 FR 58057; October 2, 2006). Dealers who attend and successfully... to renew either permit (71 FR 58057; October 2, 2006). These certificate(s) are valid for 3 years. As... National Oceanic and Atmospheric Administration RIN 0648-XC681 Schedules for Atlantic Shark...

  17. 77 FR 55464 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2012-09-10

    ... which first receives Atlantic sharks (71 FR 58057; October 2, 2006). Dealers who attend and successfully... certificate in order to renew either permit (71 FR 58057; October 2, 2006). These certificate(s) are valid for... National Oceanic and Atmospheric Administration RIN 0648-XC174 Schedules for Atlantic Shark...

  18. 77 FR 12574 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2012-03-01

    ... business listed under the shark dealer permit which first receives Atlantic sharks (71 FR 58057; October 2... permit (71 FR 58057; October 2, 2006). These certificate(s) are valid for three years. As such, vessel... National Oceanic and Atmospheric Administration RIN 0648-XB037 Schedules for Atlantic Shark...

  19. 78 FR 73500 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2013-12-06

    ... Atlantic sharks (71 FR 58057; October 2, 2006). Dealers who attend and successfully complete a workshop are... permit (71 FR 58057; October 2, 2006). These certificate(s) are valid for 3 years. As such, vessel owners... National Oceanic and Atmospheric Administration RIN 0648-XC997 Schedules for Atlantic Shark...

  20. 77 FR 32950 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2012-06-04

    ... Atlantic sharks (71 FR 58057; October 2, 2006). Dealers who attend and successfully complete a workshop are..., Release, and Identification Workshop certificate in order to renew either permit (71 FR 58057; October 2... National Oceanic and Atmospheric Administration RIN 0648-XC042 Schedules for Atlantic Shark...

  1. 76 FR 59661 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2011-09-27

    ... each business listed under the shark dealer permit which first receives Atlantic sharks (71 FR 58057... permit (71 FR 58057; October 2, 2006). These certificate(s) are valid for 3 years. As such, vessel owners... National Oceanic and Atmospheric Administration RIN 0648-XA670 Schedules for Atlantic Shark...

  2. 77 FR 73451 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2012-12-10

    ... which first receives Atlantic sharks (71 FR 58057; October 2, 2006). Dealers who attend and successfully... certificate in order to renew either permit (71 FR 58057; October 2, 2006). These ] certificate(s) are valid... National Oceanic and Atmospheric Administration RIN 0648-XC361 Schedules for Atlantic Shark...

  3. 75 FR 53665 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2010-09-01

    ... Atlantic sharks (71 FR 58057; October 2, 2006). Dealers who attend and successfully complete a workshop are..., and Identification Workshop certificate in order to renew either permit (71 FR 58057; October 2, 2006... National Oceanic and Atmospheric Administration RIN 0648-XY59 Schedules for Atlantic Shark...

  4. 75 FR 54598 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2010-09-08

    ...: Need for Correction In the Federal Register of May 28, 2010, in FR Doc. 2010-12919, on page 29992, in... National Oceanic and Atmospheric Administration RIN 0648-XW44 Schedules for Atlantic Shark Identification... cancelling the Atlantic Shark Identification workshop that was scheduled for September 2, 2010, in...

  5. 75 FR 29991 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2010-05-28

    ... listed under the shark dealer permit which first receives Atlantic sharks (71 FR 58057; October 2, 2006... permit (71 FR 58057; October 2, 2006). These certificate(s) are valid for 3 years. As such, vessel owners... National Oceanic and Atmospheric Administration RIN 0648-XW44 Schedules for Atlantic Shark...

  6. 75 FR 74693 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2010-12-01

    ... premises of each business listed under the shark dealer permit which first receives Atlantic sharks (71 FR... permit (71 FR 58057; October 2, 2006). These certificate(s) are valid for 3 years. As such, vessel owners... National Oceanic and Atmospheric Administration RIN 0648-XAO61 Schedules for Atlantic Shark...

  7. 76 FR 11762 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2011-03-03

    ... each business listed under the shark dealer permit which first receives Atlantic sharks (71 FR 58057... permit (71 FR 58057; October 2, 2006). These certificate(s) are valid for 3 years. As such, vessel owners... National Oceanic and Atmospheric Administration RIN 0648-XA213 Schedules for Atlantic Shark...

  8. A revision of the Shallow-water Azooxanthellate Scleractinia of the Western Atlantic

    NARCIS (Netherlands)

    Cairns, Stephen D.

    2000-01-01

    CAIRNS, S. D., 2000. A revision of the shallow-water azooxanthellate Scleractinia of the western Atlantic. Studies Nat. Hist. Caribbean Region 75, Amsterdam, 2000: 1-231. This paper constitutes the second of a two part revision of the western Atlantic azooxanthellate Scleractinia — this part address

  9. 76 FR 77806 - International Affairs; U.S. Fish Quotas in the Northwest Atlantic Fisheries Organization...

    Science.gov (United States)

    2011-12-14

    ... National Oceanic and Atmospheric Administration RIN 0648-XA868 International Affairs; U.S. Fish Quotas in the Northwest Atlantic Fisheries Organization Regulatory Area AGENCY: National Marine Fisheries... Northwest Atlantic Fisheries ] Organization (NAFO) Regulatory Area. This action is necessary to make...

  10. Atlantic Cod (Gadus morhua benefits from the availability of seagrass (Zostera marina nursery habitat

    Directory of Open Access Journals (Sweden)

    Richard J. Lilley

    2014-12-01

    Full Text Available The Atlantic cod (Gadus morhua is a species of significant economic and historic importance but infamous for its decline. Apart from overfishing, the causes of this decline and its subsequent lack of recovery remain largely unresolved. Indeed, the degree to which specific habitats are important for this species remains unquantified at the scale of North Atlantic. Here, the literature on the role of eelgrass meadows (Zostera marina as valuable nursery habitat for the Atlantic cod is reviewed and synthesized. Evidence is presented on relative densities of Atlantic cod in shallow water environments and in eelgrass meadows in comparison to alternative habitats. In addition, evidence pertaining to the ’viability gains’ attributed to the use of eelgrass meadows as nursery habitat (growth and survival by juvenile Atlantic cod is analyzed. Although juvenile Atlantic cod use of Z. marina is found to be facultative, when possible, available literatures indicates that they may select Z. marina as a nursery habitat where they are found in high density (average of at least 246 ha−1. From their use of Z. marina habitat the juvenile Atlantic cod receives viability benefits from it, improving their chances of reaching maturation. This paper provides strong evidence that eelgrass meadows are of significant importance to contributing to Atlantic cod stocks.

  11. 75 FR 29725 - Mid-Atlantic Fishery Management Council; Public Hearings

    Science.gov (United States)

    2010-05-27

    ... management process; the biological and socio-economic outcomes of a catch share system and how such outcomes... National Oceanic and Atmospheric Administration RIN 0648-XW67 Mid-Atlantic Fishery Management Council... Administration (NOAA), Commerce. ACTION: Notice of public meetings. SUMMARY: The Mid-Atlantic Fishery...

  12. Transferrin gene polymorphisms and population genetic studies of Atlantic cod (Gadus morhua)

    Institute of Scientific and Technical Information of China (English)

    Berhan Asmamaw

    2016-01-01

    Objective:To detect single nucleotide polymorphisms (SNPs) in the cod transferrin gene by comparing the sequences from Norwegian (North East Atlantic Ocean) and Canadian (North West Atlantic Ocean) specimen, and to quantify the genetic variation and differentiation in East and West Atlantic cod populations. Methods:cDNA sequences between individuals of Canadian (North West Atlantic Ocean) and Norwegian (North East Atlantic Ocean) origin were aligned. Allele frequencies of theSNPs were used to discriminate the different Atlantic cod populations in West/East Atlantic Ocean, and the Baltic Sea. Results: The sequence alignment detected19SNPs, of which 18 of them resulted in amino acid changes in the transferrin protein. Nonsynonymous to synonymous site substitution ratio (dn/ds) was by far greater than 1 providing an evidence for the existence of positive selection. The West Atlantic cod populations showed high values of heterozygosity and the Baltic populations were found to be inbred. Conclusions: This study identified and indicated transferrin gene polymorphisms that can be used for population differentiations.

  13. The North Atlantic Oscillation as a driver of rapid climate change in the Northern Hemisphere

    Science.gov (United States)

    Delworth, Thomas L.; Zeng, Fanrong; Vecchi, Gabriel A.; Yang, Xiaosong; Zhang, Liping; Zhang, Rong

    2016-07-01

    Pronounced climate changes have occurred since the 1970s, including rapid loss of Arctic sea ice, large-scale warming and increased tropical storm activity in the Atlantic. Anthropogenic radiative forcing is likely to have played a major role in these changes, but the relative influence of anthropogenic forcing and natural variability is not well established. The above changes have also occurred during a period in which the North Atlantic Oscillation has shown marked multidecadal variations. Here we investigate the role of the North Atlantic Oscillation in these rapid changes through its influence on the Atlantic meridional overturning circulation and ocean heat transport. We use climate models to show that observed multidecadal variations of the North Atlantic Oscillation can induce multidecadal variations in the Atlantic meridional overturning circulation and poleward ocean heat transport in the Atlantic, extending to the Arctic. Our results suggest that these variations have contributed to the rapid loss of Arctic sea ice, Northern Hemisphere warming, and changing Atlantic tropical storm activity, especially in the late 1990s and early 2000s. These multidecadal variations are superimposed on long-term anthropogenic forcing trends that are the dominant factor in long-term Arctic sea ice loss and hemispheric warming.

  14. Mid-Atlantic Consumer Purchasing Behavior and Knowledge of Locally Grown and Seasonal Produce

    Science.gov (United States)

    Chamberlain, Amy J.; Kelley, Kathleen M.; Hyde, Jeffrey

    2013-01-01

    Mid-Atlantic urban consumers were surveyed on their fruit and vegetable purchasing behaviors and their knowledge of produce grown in the region. Consumers were generally unaware of what produce is grown in the mid-Atlantic and during what months they are harvested. Additionally, differences pertaining to number of produce items purchased were…

  15. 50 CFR 224.105 - Speed restrictions to protect North Atlantic Right Whales.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Speed restrictions to protect North Atlantic Right Whales. 224.105 Section 224.105 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE... AND ANADROMOUS SPECIES § 224.105 Speed restrictions to protect North Atlantic Right Whales. (a)...

  16. Observed trends of anthropogenic acidification in North Atlantic water masses

    Directory of Open Access Journals (Sweden)

    M. Vázquez-Rodríguez

    2012-03-01

    Full Text Available The lack of observational pH data has made difficult assessing recent rates of ocean acidification, particularly in the high latitudes. Here we present a time series of high-quality carbon system measurements in the North Atlantic, comprising fourteen cruises spanning over 27 yr (1981–2008 and covering important water mass formation areas like the Irminger and Iceland basins. We provide direct quantification of anthropogenic acidification rates in upper and intermediate North Atlantic waters by removing the natural variability of pH from the observations. Bottle data were normalised to basin-average conditions using climatological data and further condensed into averages per water mass and year to examine the temporal trends. The highest acidification rates of all inspected water masses were associated with surface waters in the Irminger Sea (−0.0018 ± 0.0001 yr−1 and the Iceland Basin (−0.0012 ± 0.0002 yr−1 and, unexpectedly, with Labrador Seawater (LSW which experienced an unprecedented pH drop of −0.0015 ± 0.001 yr−1. The latter stems from the formation by deep convection and the rapid propagation in the North Atlantic subpolar gyre of this well-ventilated water mass. The high concentrations of anthropogenic CO2 are effectively transported from the surface into intermediate waters faster than via downward diffusion, thus accelerating the acidification rates of LSW. An extrapolation of the observed lineal trends of acidification suggests that the pH of LSW could drop 0.45 units with respect to pre-industrial levels by the time atmospheric CO2 concentrations double the present ones.

  17. Turtle riders: remoras on marine turtles in Southwest Atlantic

    Directory of Open Access Journals (Sweden)

    Ivan Sazima

    2006-03-01

    Full Text Available An overview is presented for a poorly documented relationship between reef vertebrates in Southwest Atlantic: remoras (Echeneidae associated with marine turtles. Two remora species (Echeneis naucrates and Remora remora and four turtle species (Caretta caretta, Chelonia mydas, Eretmochelys imbricata, and Dermochelys coriacea are here recorded in symbiotic associations in the SW Atlantic. Echeneis naucrates was recorded both on the coast and on oceanic islands, whereas R. remora was recorded only at oceanic islands and in the open sea. The remora-turtle association is usually regarded as an instance of phoresis (hitchhiking, albeit feeding by the fish is also involved in this symbiosis type. This association seems to be rare in SW Atlantic.Uma visão geé apresentada sobre uma relação pouco documentada entre vertebrados recifais no Atlântico Sul Ocidental: rêmoras (Echeneidae associadas a tartarugas marinhas. Duas espécies de rêmora ou pegador (Echeneis naucrates e Remora remora e quatro de tartarugas (Caretta caretta, Chelonia mydas, Eretmochelys imbricata e Dermochelys coriacea são aqui registradas em associações simbiônticas para o Atlântico Sul Ocidental. Echeneis naucrates foi registrada tanto na costa como em ilhas oceânicas, ao passo que R. remora foi registrada somente em ilhas oceânicas e região pelágica. A associação entre rêmoras e tartarugas é habitualmente considerada como forese, embora forrageamento, por parte das rêmoras, também esteja envolvido neste tipo de simbiose. Esta associação parece ser rara no Atlântico Sul Ocidental.

  18. Atlantic leatherback migratory paths and temporary residence areas.

    Directory of Open Access Journals (Sweden)

    Sabrina Fossette

    Full Text Available BACKGROUND: Sea turtles are long-distance migrants with considerable behavioural plasticity in terms of migratory patterns, habitat use and foraging sites within and among populations. However, for the most widely migrating turtle, the leatherback turtle Dermochelys coriacea, studies combining data from individuals of different populations are uncommon. Such studies are however critical to better understand intra- and inter-population variability and take it into account in the implementation of conservation strategies of this critically endangered species. Here, we investigated the movements and diving behaviour of 16 Atlantic leatherback turtles from three different nesting sites and one foraging site during their post-breeding migration to assess the potential determinants of intra- and inter-population variability in migratory patterns. METHODOLOGY/PRINCIPAL FINDINGS: Using satellite-derived behavioural and oceanographic data, we show that turtles used Temporary Residence Areas (TRAs distributed all around the Atlantic Ocean: 9 in the neritic domain and 13 in the oceanic domain. These TRAs did not share a common oceanographic determinant but on the contrary were associated with mesoscale surface oceanographic features of different types (i.e., altimetric features and/or surface chlorophyll a concentration. Conversely, turtles exhibited relatively similar horizontal and vertical behaviours when in TRAs (i.e., slow swimming velocity/sinuous path/shallow dives suggesting foraging activity in these productive regions. Migratory paths and TRAs distribution showed interesting similarities with the trajectories of passive satellite-tracked drifters, suggesting that the general dispersion pattern of adults from the nesting sites may reflect the extent of passive dispersion initially experienced by hatchlings. CONCLUSIONS/SIGNIFICANCE: Intra- and inter-population behavioural variability may therefore be linked with initial hatchling drift scenarios

  19. Ozone in the Atlantic Ocean marine boundary layer

    Directory of Open Access Journals (Sweden)

    Patrick Boylan

    2015-04-01

    Full Text Available Abstract In situ atmospheric ozone measurements aboard the R/V Ronald H. Brown during the 2008 Gas-Ex and AMMA research cruises were compared with data from four island and coastal Global Atmospheric Watch stations in the Atlantic Ocean to examine ozone transport in the marine boundary layer (MBL. Ozone measurements made at Tudor Hill, Bermuda, were subjected to continental outflow from the east coast of the United States, which resulted in elevated ozone levels above 50 ppbv. Ozone measurements at Cape Verde, Republic of Cape Verde, approached 40 ppbv in springtime and were influenced by outflow from Northern Africa. At Ragged Point, Barbados, ozone levels were ∼ 21 ppbv; back trajectories showed the source region to be the middle of the Atlantic Ocean. Ozone measurements from Ushuaia, Argentina, indicated influence from the nearby city; however, the comparison of the daily maxima ozone mole fractions measured at Ushuaia and aboard the Gas-Ex cruise revealed that these were representative of background ozone in higher latitudes of the Southern Hemisphere. Diurnal ozone cycles in the shipborne data, frequently reaching 6–7 ppbv, were larger than most previous reports from coastal or island monitoring locations and simulations based on HOx photochemistry alone. However, these data show better agreement with recent ozone modeling that included ozone-halogen chemistry. The transport time between station and ship was estimated from HYSPLIT back trajectories, and the change of ozone mole fractions during transport in the MBL was estimated. Three comparisons showed declining ozone levels; in the subtropical and tropical North Atlantic Ocean the loss of ozone was < 1.5 ppbv day−1. Back trajectories at Ushuaia were too inconsistent to allow for this determination. Comparisons between ship and station measurements showed that ozone behavior and large-scale (∼ 1000 km multi-day transport features were well retained during transport in the MBL.

  20. Reversed North Atlantic gyre dynamics in present and glacial climates

    Energy Technology Data Exchange (ETDEWEB)

    Montoya, Marisa [Universidad Complutense de Madrid, Ciudad Universitaria, Dpto. Astrofisica y Ciencias de la Atmosfera, Facultad de Ciencias Fisicas, Madrid (Spain); Born, Andreas [Bjerknes Centre for Climate Research, Bergen (Norway); University of Bergen, Geophysical Institute, Bergen (Norway); Levermann, Anders [Earth System Analysis, Potsdam Institute for Climate Impact Research, Potsdam (Germany); Potsdam University, Institute of Physics, Potsdam (Germany)

    2011-03-15

    The dynamics of the North Atlantic subpolar gyre (SPG) are assessed under present and glacial boundary conditions by investigating the SPG sensitivity to surface wind-stress changes in a coupled climate model. To this end, the gyre transport is decomposed in Ekman, thermohaline, and bottom transports. Surface wind-stress variations are found to play an important indirect role in SPG dynamics through their effect on water-mass densities. Our results suggest the existence of two dynamically distinct regimes of the SPG, depending on the absence or presence of deep water formation (DWF) in the Nordic Seas and a vigorous Greenland-Scotland ridge (GSR) overflow. In the first regime, the GSR overflow is weak and the SPG strength increases with wind-stress as a result of enhanced outcropping of isopycnals in the centre of the SPG. As soon as a vigorous GSR overflow is established, its associated positive density anomalies on the southern GSR slope reduce the SPG strength. This has implications for past glacial abrupt climate changes, insofar as these can be explained through latitudinal shifts in North Atlantic DWF sites and strengthening of the North Atlantic current. Regardless of the ultimate trigger, an abrupt shift of DWF into the Nordic Seas could result both in a drastic reduction of the SPG strength and a sudden reversal in its sensitivity to wind-stress variations. Our results could provide insight into changes in the horizontal ocean circulation during abrupt glacial climate changes, which have been largely neglected up to now in model studies. (orig.)

  1. Last interglacial temperature seasonality reconstructed from tropical Atlantic corals

    Science.gov (United States)

    Brocas, William M.; Felis, Thomas; Obert, J. Christina; Gierz, Paul; Lohmann, Gerrit; Scholz, Denis; Kölling, Martin; Scheffers, Sander R.

    2016-09-01

    Reconstructions of last interglacial (LIG, MIS 5e, ∼127-117 ka) climate offer insights into the natural response and variability of the climate system during a period partially analogous to future climate change scenarios. We present well preserved fossil corals (Diploria strigosa) recovered from the southern Caribbean island of Bonaire (Caribbean Netherlands). These have been precisely dated by the 230Th/U-method to between 130 and 120 ka ago. Annual banding of the coral skeleton enabled construction of time windows of monthly resolved strontium/calcium (Sr/Ca) temperature proxy records. In conjunction with a previously published 118 ka coral record, our eight records of up to 37 years in length, cover a total of 105 years within the LIG period. From these, sea surface temperature (SST) seasonality and variability in the tropical North Atlantic Ocean is reconstructed. We detect similar to modern SST seasonality of ∼2.9 °C during the early (130 ka) and the late LIG (120-118 ka). However, within the mid-LIG, a significantly higher than modern SST seasonality of 4.9 °C (at 126 ka) and 4.1 °C (at 124 ka) is observed. These findings are supported by climate model simulations and are consistent with the evolving amplitude of orbitally induced changes in seasonality of insolation throughout the LIG, irrespective of wider climatic instabilities that characterised this period. The climate model simulations suggest that the SST seasonality changes documented in our LIG coral Sr/Ca records are representative of larger regions within the tropical North Atlantic. These simulations also suggest that the reconstructed SST seasonality increase during the mid-LIG is caused primarily by summer warming. A 124 ka old coral documents, for the first time, evidence of decadal SST variability in the tropical North Atlantic during the LIG, akin to that observed in modern instrumental records.

  2. Oxygen trends over five decades in the North Atlantic

    Science.gov (United States)

    Stendardo, I.; Gruber, N.

    2012-11-01

    We investigate long-term trends in dissolved oxygen in the North Atlantic from 1960 to 2009 on the basis of a newly assembled high-quality dataset consisting of oxygen data from three different sources: CARINA, GLODAP and the World Ocean Database. Oxygen trends are determined along isopycnal surfaces for eight regions and five water masses using a general least-squares linear regression method that accounts for temporal auto-correlation. Our results show a significant decrease of oxygen in the Upper (UW), Mode (MW) and Intermediate (IW) waters in almost all regions over the last 5 decades. Over the same period, oxygen increased in the Lower Intermediate Water (LIW) and Labrador Sea Water (LSW) throughout the North Atlantic. The observed oxygen decreases in the MW and IW of the northern and eastern regions are largely driven by changes in circulation and/or ventilation, while changes in solubility are the main driver for the oxygen decrease in the UW and the increases in the LIW and LSW. From 1960 until 2009 the UW, MW, and IW horizons have lost a total of -57 ± 34 Tmol, while the LIW and LSW horizons have gained 46 ± 47 Tmol, integrating to a roughly constant oxygen inventory in the North Atlantic. Comparing our oxygen trends with those of the oceanic heat content, we find an O2 to heat change ratio of -3.6 ± 2.8 nmol J-1 for the UW, MW and IW, and a ratio of -2.8 ± 3.4 nmol J-1 for the LIW and LSW. These ratios are substantially larger than those expected from solubility alone.

  3. Shear zone reactivation during South Atlantic rifting in NW Namibia

    Science.gov (United States)

    Koehn, D.; Passchier, C. W.; Salomon, E.

    2013-12-01

    Reactivation of inherited structures during rifting as well as an influence of inherited structures on the orientation of a developing rift has long been discussed (e.g. Piqué & Laville, 1996; Younes & McClay, 2002). Here, we present a qualitative and quantitative study of shear zone reactivation during the South Atlantic opening in NW Namibia. The study area comprises the Neo-Proterozoic rocks of the Kaoko Belt which was formed during the amalgamation of Gondwana. The Kaoko Belt encompasses the prominent ~500 km long ductile Purros shear zone and the Three Palms shear zone, both running sub-parallel to the present continental margin. The Kaoko Belt is partly overlain by the basalts of the Paraná-Etendeka Large Igneous Province, which with an age of ~133 Ma were emplaced just before or during the onset of the Atlantic rifting at this latitude. Combining the analysis of satellite imagery and digital elevation models with extensive field work, we identified numerous faults tracing the old shear zones along which the Etendeka basalts were down-faulted. The faults are often listric, yet we also found evidence for a regional scale basin formation. Our analysis allowed for constructing the geometry of three of these faults and we could thus estimate the vertical offsets to ~150 m, ~500 m, and ~1100 m, respectively. Our results contribute to the view that the basement inheritance plays a significant role on rifting processes and that the reactivation of shear zones can accumulate significant amounts of displacement. References: Pique, A. and E. Laville (1996). The Central Atlantic rifting: Reactivation of Paleozoic structures?. J. Geodynamics, 21, 235-255. Younes, I.A. and K. McClay (2002). Development of accommodation zones in the Gulf of Suez-Red Sea rift, Egypt. AAPG Bulletin, 86, 1003-1026.

  4. A New North Atlantic Oscillation Index and Its Variability

    Institute of Scientific and Technical Information of China (English)

    LI Jianping(李建平); Julian X.L.WANG

    2003-01-01

    A new North Atlantic Oscillation (NAO) index, the NAOI, is defined as the differences of normalizedsea level pressures regionally zonal-averaged over a broad range of longitudes 80°W-30°E. A comprehensivecomparison of six NAO indices indicates that the new NAOI provides a more faithful representation ofthe spatial-temporal variability associated with the NAO on all timescales. A very high signal-to-noiseratio for the NAOI exists for all seasons, and the life cycle represented by the NAOI describes well theseasonal migration for action centers of the NAO. The NAOI captures a larger fraction of the variance ofsea level pressure over the North Atlantic sector (20°-90°N, 80°W-30°E), on average 10% more than anyother NAO index. There are quite different relationships between the NAOI and surface air temperatureduring winter and summer. A novel feature, however, is that the NAOI is significantly negative correlatedwith surface air temperature over the North Atlantic Ocean between 10°-25°N and 70°-30°W, whetherin winter or summer. From 1873, the NAOI exhibits strong interannual and decadal variability. Itsinterannual variability of the twelve calendar months is obviously phase-locked with the seasonal cycle.Moreover, the annual NAOI exhibits a clearer decadal variability in amplitude than the winter NAOI. Anupward trend is found in the annual NAOI between the 1870s and 1910s, while the other winter NAOindices fail to show this tendency. The annual NAOI exhibits a strongly positive epoch of 50 years between1896 and 1950. After 1950, the variability of the annual NAOI is very similar to that of the winter NAOindices.

  5. Atlantic Offshore Seabird Dataset Catalog, Atlantic Coast and Outer Continental Shelf, from 1938-01-01 to 2013-12-31 (NODC Accession 0115356)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Several bureaus within the Department of Interior compiled available information from seabird observation datasets from the Atlantic Outer Continental Shelf into a...

  6. Historical North Atlantic Tropical Cyclone Tracks 1851-2005, Geographic NAD83, NOAA (2006) [atlantic_hurricane_tracks_1851_2005_NOAA_2006

    Data.gov (United States)

    Louisiana Geographic Information Center — This Historical North Atlantic Tropical Cyclone Tracks file contains the 6-hourly (0000, 0600, 1200, 1800 UTC) center locations and intensities for all subtropical...

  7. Water quality issues as potential limiting factors affecting juvenile Atlantic salmon life stages in Maine rivers: A report to the Maine Atlantic Salmon Technical Advisory Committee

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Signatories to the Maine Atlantic Salmon Technical Advisory Committee (TAC), in a letter to the TAC chair, requested guidance to resolve the issue whether water...

  8. AtlanticCanyons2011: Exploration and Research of Mid-Atlantic Deepwater hard Bottom Habitats and Shipwrecks with Emphasis on Canyons and Coral Communities between 20110604 and 20110617

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is an interagency study that focuses on the exploration and investigation of deepwater hard bottom biological communities located in the northwest Atlantic...

  9. 75 FR 39917 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Coral and Coral Reefs off the...

    Science.gov (United States)

    2010-07-13

    ..., and South Atlantic; Coral and Coral Reefs off the Southern Atlantic States; Exempted Fishing Permit... for Coral, Coral Reefs, and Live/Hardbottom Habitat of the South Atlantic Region. The applicant has... Coral Reef Research Foundation (CRRF, http://www.coralreefresearchfoundation.org/ ). Samples would...

  10. 76 FR 12882 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery of the...

    Science.gov (United States)

    2011-03-09

    ..., Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery of the South Atlantic; Closure AGENCY..., fax: 727-824-5308, e-mail: Catherine.Bruger@noaa.gov . SUPPLEMENTARY INFORMATION: The snapper-grouper fishery of the South Atlantic is managed under the Fishery Management Plan for the Snapper-...

  11. 75 FR 60009 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery of the...

    Science.gov (United States)

    2010-09-29

    ..., Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery of the South Atlantic; Closure of the July- December 2010 Commercial Sector for Vermilion Snapper in the South Atlantic AGENCY: National Marine...: Temporary rule; closure. SUMMARY: NMFS closes the commercial sector for vermilion snapper in the...

  12. 78 FR 76285 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery Off the...

    Science.gov (United States)

    2013-12-17

    ... Plan for the Snapper-Grouper Fishery in the South Atlantic Region (74 FR 1621, January 13, 2009) and... Regulatory Amendment 17 was published in the Federal Register on December 4, 2013 (78 FR 72867) and requested..., and South Atlantic; Snapper-Grouper Fishery Off the South Atlantic States; Regulatory Amendment...

  13. 78 FR 10102 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Resources of the...

    Science.gov (United States)

    2013-02-13

    ... Office of the Federal Register. As implemented by the final rule for Regulatory Amendment 12 (77 FR 61295..., Gulf of Mexico, and South Atlantic; Snapper-Grouper Resources of the South Atlantic; Trip Limit... . SUPPLEMENTARY INFORMATION: The snapper-grouper fishery includes golden tilefish in the South Atlantic and...

  14. 77 FR 11477 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery off the...

    Science.gov (United States)

    2012-02-27

    ... ACLs were implemented through Amendment 17B to the FMP (75 FR 82280, December 30, 2010), before black..., Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery off the Southern Atlantic States; Amendment... Snapper- Grouper Fishery of the South Atlantic Region (FMP) for review, approval, and implementation...

  15. 75 FR 51001 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper and Grouper Off the...

    Science.gov (United States)

    2010-08-18

    ..., and South Atlantic; Snapper and Grouper Off the Southern Atlantic States AGENCY: National Marine... catch and discard mortality within the South Atlantic commercial hook-and-line snapper-grouper fishery... CFR 622 implementing the Fishery Management Plan for the Snapper-Grouper Fishery of the South...

  16. 75 FR 18427 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery of the...

    Science.gov (United States)

    2010-04-12

    ..., Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery of the South Atlantic; Closure AGENCY...-5308, e-mail Catherine.Bruger@noaa.gov . SUPPLEMENTARY INFORMATION: The snapper-grouper fishery of the South Atlantic is managed under the Fishery Management Plan for the Snapper- Grouper Fishery of...

  17. 77 FR 4754 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery off the...

    Science.gov (United States)

    2012-01-31

    ... allocation formula implemented through the final rule for Amendment 13C to the FMP (71 FR 55096, September 21..., Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery off the Southern Atlantic States; Amendment... Management Plan (FMP) for the Snapper-Grouper Fishery of the South Atlantic Region (Amendment 18A) for...

  18. 76 FR 23930 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery of the...

    Science.gov (United States)

    2011-04-29

    ... Snapper and Gag Commercial Trip Limits Amendment 17B to the FMP (75 FR 82280, December 30, 2010), recently... Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery of the South Atlantic; Snapper...) to the Fishery Management Plan for the Snapper-Grouper Fishery of the South Atlantic Region...

  19. 75 FR 44753 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery off the...

    Science.gov (United States)

    2010-07-29

    ..., Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery off the Southern Atlantic States; Amendment... (NOAA), Commerce. ACTION: Notice of Availability of Amendment 17A to South Atlantic Snapper-Grouper... (Council) has submitted Amendment 17A to the Fishery Management Plan for the Snapper- Grouper Fishery...

  20. 77 FR 65356 - Fisheries of the Caribbean, Gulf of Mexico and South Atlantic; Snapper-Grouper Fishery Off the...

    Science.gov (United States)

    2012-10-26

    ..., Gulf of Mexico and South Atlantic; Snapper-Grouper Fishery Off the Southern Atlantic States; Amendment... Plan (FMP) for the Snapper-Grouper Fishery of the South Atlantic (Amendment 18B) for review, approval... endorsement program for the commercial golden tilefish component of the snapper- grouper fishery;...

  1. 77 FR 8749 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery of the...

    Science.gov (United States)

    2012-02-15

    ..., Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery of the South Atlantic; Closure AGENCY...-824- 5305, email: Catherine.Bruger@noaa.gov . SUPPLEMENTARY INFORMATION: The snapper-grouper fishery of the South Atlantic is managed under the Fishery Management Plan for the Snapper- Grouper...

  2. 76 FR 78879 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery Off the...

    Science.gov (United States)

    2011-12-20

    ... (December 30, 2010, 75 FR 82280). This ACL prohibits all harvest and possession of speckled hind and warsaw..., Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery Off the Southern Atlantic States; Snapper... Management Plan for the Snapper-Grouper Fishery of the South Atlantic Region (FMP), as prepared by the...

  3. 78 FR 11628 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery of the...

    Science.gov (United States)

    2013-02-19

    ..., and South Atlantic; Snapper-Grouper Fishery of the South Atlantic; Exempted Fishing Permit AGENCY... a charter vessel to collect a total of 125-150 adult red snapper, south of the Florida Keys and near... connectivity, and life history of red snapper would provide the South Atlantic Fishery Management...

  4. 78 FR 72868 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery Off the...

    Science.gov (United States)

    2013-12-04

    ... bass commercial and recreational ACLs were increased through Regulatory Amendment 19 to the FMP (78 FR..., and South Atlantic; Snapper-Grouper Fishery Off the South Atlantic States; Regulatory Amendment 16... Snapper-Grouper Fishery of the South Atlantic Region (Regulatory Amendment 16). Regulatory Amendment...

  5. 78 FR 61939 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Resources of the...

    Science.gov (United States)

    2013-10-07

    ... Office of the Federal Register, as implemented by the final rule for Regulatory Amendment 18 (78 FR 47574..., Gulf of Mexico, and South Atlantic; Snapper-Grouper Resources of the South Atlantic; Trip Limit... trip limit for vermilion snapper in or from the exclusive economic zone (EEZ) of the South Atlantic...

  6. 76 FR 23205 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery of the...

    Science.gov (United States)

    2011-04-26

    ... FR 12883, March 9, 2011). However, based on current statistics, NMFS has determined that only 83..., Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery of the South Atlantic; Reopening of the Commercial Sector for Vermilion Snapper in the South Atlantic AGENCY: National Marine Fisheries Service...

  7. 76 FR 100 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Amendment 21 to the Snapper...

    Science.gov (United States)

    2011-01-03

    ... commercial sector closures. It is anticipated that, under status quo management, incentives for derby..., and South Atlantic; Amendment 21 to the Snapper-Grouper Fishery Management Plan of the South Atlantic... comments. SUMMARY: NMFS, Southeast Region, in collaboration with the South Atlantic Fishery...

  8. 33 CFR 165.156 - Regulated Navigation Area: East Rockaway Inlet to Atlantic Beach Bridge, Nassau County, Long...

    Science.gov (United States)

    2010-07-01

    ..., thence easterly along the shore to the east side of the Atlantic Beach Bridge, State Route 878, over East... Rockaway Inlet to Atlantic Beach Bridge, Nassau County, Long Island, New York. 165.156 Section 165.156... to Atlantic Beach Bridge, Nassau County, Long Island, New York. (a) Location. The following area is...

  9. Continental shelf processes affecting the oceanography of the South Atlantic Bight. Progress report, June 1, 1978--May 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Atkinson, L P

    1979-03-01

    Progress is reported on the following research projects: nitrogen inputs to the South Atlantic Bight; eddy experiments for obtaining quasi-synoptic map of South Atlantic Bight; cruise experiment for observation of stranded intrusion in the South Atlantic Bight; geographic distribution of hydrographic data; and computer plotting and contouring of data. (HLW)

  10. Atlantic forcing of Amazonian climates in the last ice age

    Science.gov (United States)

    Bush, M. B.; Mosblech, N.; Valencia, B. G.; Hodell, D. A.; Gosling, W. D.; Van Calsteren, P. W.; Thomas, L. E.; Curtis, J. H.

    2011-12-01

    An absence of study sites means that the relative influence of orbitally driven presession cycles and millenial scale variability upon ice-age Amazonian precipitation is unknown. Here we present a continuous isotopic (δO18 and C13) record spanning the period from ~93-8 ka, from the aseasonal forests of Amazonian Ecuador. The variability in δO18 depletion is probably related to the relative strength of evapotranspired moisture (less depleted) and tropical Atlantic moisture carried across the basin by the South American Low Level Jet (more depleted). Times of strengthened South American Low Level Jet probably correspond to increased overall moisture availability and hence elevated precipitation. The occurrence of markedly depleted δO18 signatures during Heinrich events suggests a strong influence of the Atlantic Ocean on this system, and that these northern hemispheric stadials induced wet episodes in western Amazonia. Weakening of the Atlantic Meridional Overturning Circulation (AMOC) has been suggested to strengthen the South American Low Level Jet. The isotopic records reveal strong cohesion with previously published records from southern Brazil. A precessional influence amplifies the north Atlantic signal between c. 93 ka and 50 ka. However, after c. 50 ka the precessional signal weakens, perhaps sugesting that at a critical size the Laurentide ice mass exerted a strong influence on Neotropical climates suppressing the weaker forcing associated with precession. Contrary to long-standing expectation, the Last Glacial Maximum (21 ± 2 ka) does not stand out as time of aridity in this record. However, between c. 35 ka and 18 ka there is a drift toward less depleted rainfall. One hypothesis to account for this observation is that the climate was becoming more seasonal as the Intertropical Convergence Zone (ITCZ) formed further south than its modern location. The resulting weakened influence of the South American Summer Monsoon (SASM) would probably reduce wet

  11. Atlantic Forest. A natural reservoir of chemical elements

    International Nuclear Information System (INIS)

    The accumulation of chemical elements in biological compartments is one of the strategies of tropical species to adapt to a low-nutrient soil. This study focuses on the Atlantic Forest because of its eco-environmental importance as a natural reservoir of chemical elements. About 20 elements were determined by INAA in leaf, soil, litter and epiphyte compartments. There was no seasonality for chemical element concentrations in leaves, which probably indicated the maintenance of chemical elements in this compartment. Considering the estimated quantities, past deforestation events could have released large amounts of chemical elements to the environment. (author)

  12. Taxonomic novelties in Mikania (Asteraceae: Eupatorieae) from Atlantic Forest, Brazil

    OpenAIRE

    Borges, R.A.X.; Forzza, R.C.; Fraga, C.N.

    2010-01-01

    During studies of Brazilian Atlantic Forest Asteraceae, a new species and a replacement name were determined: Mikania amorimii from Bahia State and Mikania capixaba from Espírito Santo State. The former is a new species related to M. ternata but distinct by its leaves, involucral bracts and cypsela morphology. The latter is proposed as a replacement name for Mikania dentata G.M.Barroso, a later homonym of M. dentata Spreng. Line drawings and comments about conservation status are made for bot...

  13. Host specificity and phylogenetic relationships among Atlantic Ovulidae (Mollusca: Gastropoda)

    OpenAIRE

    Reijnen, B.T.; Hoeksema, B.W.; Gittenberger, E.

    2010-01-01

    Ovulid gastropods and their octocoral hosts were collected along the leeward coast of Curaçao, Netherlands Antilles. New molecular data of Caribbean and a single Atlantic species were combined with comparable data of Indo-Pacific Ovulidae and a single East-Pacific species from GenBank. Based on two DNA markers, viz. CO-I and 16S, the phylogenetic relationships among all ovulid species of which these data are available are reconstructed. The provisional results suggest a dichotomy between the ...

  14. Valuable biomolecules from nine North Atlantic red macroalgae

    DEFF Research Database (Denmark)

    Razi Parjikolaei, Behnaz; Bruhn, Annette; Eybye, Karin Loft;

    2016-01-01

    In modern society, novel marine resources are scrutinized pursuing compounds of use in the medical, pharmaceutical, biotech, food or feed industry. Few of the numerous marine macroalgae are currently exploited. In this study, the contents of nutritional compounds from nine common North Atlantic red...... macroalgae were compared: the lipid content was low and constant among the species, whereas the fatty acid profiles indicated that these species constitute interesting sources of polyunsaturated fatty acids (PUFA). The dominating essential and non-essential amino acids were lysine and leucine, aspartic acid...

  15. Energy situation in the Mid-Atlantic region

    Energy Technology Data Exchange (ETDEWEB)

    Munson, J S; Brainard, J P

    1977-08-01

    This report presents a review of the energy situation in the Mid-Atlantic Region. It describes the patterns of energy production, supply and demand by state and compares these to national and regional averages. It presents a picture of existing energy and environmental interactions and a view of potential energy and environmental conflicts. A review of the major issues by energy sector is included as is a description of the existing energy actors and major energy programs for Ohio, West Virginia, Virginia, Pennsylvania, New Jersey, New York, Delaware, Maryland, Puerto Rico, Virgin Islands, and Washington, DC.

  16. Transport of AABW through the Kane Gap, tropical NE Atlantic

    OpenAIRE

    E. G. Morozov; R. Yu. Tarakanov; Van Haren, H.

    2013-01-01

    We study low-frequency flow of Antarctic Bottom Water through the Kane Gap (9° N) in the Atlantic. The measurements in the Kane Gap include five visits with CTD sections in 2009–2012 and a year-long record of currents using three AquaDopp current-meters. We found an alternating regime of flow, which changes direction several times during a year. The velocities reach 0.21 m s−1. The transport of Antarctic Bottom Water (< 1.9 °C) based on the mooring and LADCP data varies by &...

  17. East Greenland Ridge in the North Atlantic Ocean

    DEFF Research Database (Denmark)

    Andreasen, Arne Døssing; Dahl-Jensen, T.; Thybo, Hans;

    2008-01-01

    The combined Greenland-Senja Fracture Zones (GSFZ) represent a first-order plate tectonic feature in the North Atlantic Ocean. The GSFZ defines an abrupt change in the character of magnetic anomalies with well-defined seafloor spreading anomalies in the Greenland and Norwegian basins to the south...... but ambiguous and weak magnetic anomalies in the Boreas Basin to the north. Substantial uncertainty exists concerning the plate tectonic evolution of the latter area, including the role of the East Greenland Ridge, which is situated along the Greenland Fracture Zone. In 2002, a combined ocean-bottom seismometer...

  18. Aerosol isotopic ammonium signatures over the remote Atlantic Ocean

    Science.gov (United States)

    Lin, C. T.; Jickells, T. D.; Baker, A. R.; Marca, A.; Johnson, M. T.

    2016-05-01

    We report aerosol ammonium 15N signatures for samples collected from research cruises on the South Atlantic and Caribbean using a new high sensitivity method. We confirm a pattern of isotopic signals from generally light (δ15N -5 to -10‰), for aerosols with very low (ocean, to generally heavier values (δ15N +5 to +10‰), for aerosols collected in temperate and tropical latitudes and with higher ammonium concentrations (>2  nmol m-3). We discuss whether this reflects a mixing of aerosols from two end-members (polluted continental and remote marine emissions), or isotopic fractionation during aerosol transport.

  19. Radon levels and transport parameters in Atlantic Forest soils

    International Nuclear Information System (INIS)

    In natural forest soils, the radon transport processes can be significantly intensified due to the contribution of living organism activities to soil porosity. In this paper, the first results of the radon concentrations were obtained for soil gas from the Atlantic Forest, particularly in the Refugio Ecologico Charles Darwin, Brazil. The estimation of permeability and radon exhalation rate were carried out in this conservation unit. For forested soils, radon concentrations as high as 40 kBq m-3 were found. Based on the radon concentrations and on the permeability parameter, the results indicated considerable radon hazard for human occupation in the neighborhood. (author)

  20. Patagonian and southern South Atlantic view of Holocene climate

    Science.gov (United States)

    Kaplan, M. R.; Schaefer, J. M.; Strelin, J. A.; Denton, G. H.; Anderson, R. F.; Vandergoes, M. J.; Finkel, R. C.; Schwartz, R.; Travis, S. G.; Garcia, J. L.; Martini, M. A.; Nielsen, S. H. H.

    2016-06-01

    We present a comprehensive 10Be chronology for Holocene moraines in the Lago Argentino basin, on the east side of the South Patagonian Icefield. We focus on three different areas, where prior studies show ample glacier moraine records exist because they were formed by outlet glaciers sensitive to climate change. The 10Be dated records are from the Lago Pearson, Herminita Península-Brazo Upsala, and Lago Frías areas, which span a distance of almost 100 km adjacent to the modern Icefield. New 10Be ages show that expanded glaciers and moraine building events occurred at least at 6120 ± 390 (n = 13), 4450 ± 220 (n = 7), 1450 or 1410 ± 110 (n = 18), 360 ± 30 (n = 5), and 240 ± 20 (n = 8) years ago. Furthermore, other less well-dated glacier expansions of the Upsala Glacier occurred between ~1400 and ∼1000 and ∼2300 and ∼2000 years ago. The most extensive glaciers occurred over the interval from ∼6100 to ∼4500 years ago, and their margins over the last ∼600 years were well within and lower than those in the middle Holocene. The 10Be ages agree with 14C-limiting data for the glacier histories in this area. We then link southern South American, adjacent South Atlantic, and other Southern Hemisphere records to elucidate broader regional patterns of climate and their possible causes. In the early Holocene, a far southward position of the westerly winds fostered warmth, small Patagonian glaciers, and reduced sea ice coverage over the South Atlantic. Although we infer a pronounced southward displacement of the westerlies during the early Holocene, these conditions did not occur throughout the southern mid-high latitudes, an important exception being over the southwest Pacific sector. Subsequently, a northward locus and/or expansion of the winds over the Patagonia-South Atlantic sector promoted the largest glaciers between ∼6100 and ∼4500 years ago and greatest sea ice coverage. Over the last few millennia, the South Patagonian Icefield has experienced

  1. A lithospheric 3D temperature study from the South Atlantic

    Science.gov (United States)

    Hirsch, K. K.; Scheck-Wenderoth, M.; Maystrenko, Y.; Sippel, J.

    2009-04-01

    The East African continental margin is a passive volcanic margin that experienced a long post-rifting history after break up in Early Cretaceous times. The break up resulted in the formation of a number of basins along the margin. The by far largest depocentre in the South Atlantic, the Orange Basin, was the location of previously performed studies. These studies of the Orange Basin have been performed to investigate the crustal structure and the temperature evolution of the basin. In this way, they gave way to new insights and to a number of questions. With 3D gravity modelling we found the crust to include high density bodies. Furthermore, a rifting model was developed which explained both the geometry and the thermal constraints of the basin. Now, this study has been extended spatially to cover a larger area and into depth to include the deep lithosphere. The main goal is to combine information on the geometry and properties of the sedimentary part of the system with data on the geometry and physical properties of the deep crust. It was also aimed to integrate both the continental and the oceanic parts of the margin into a consistent 3D structural model on a lithospheric scale. A 3D temperature model was evaluated for the passive continental margin of the South Atlantic including the lithospheric structure of the margin. We evaluate a case study for different scenarios to estimate the influence of sediments and crustal structures on the thermal field. The calculated conductive field is constrained by temperature measurements and 3D gravity modelling. At the Norwegian continental margin it has been found that a differentiation of the physical properties of the lower crust and the mantle is needed between the oceanic and continental domains to explain the observations. We aim to compare the younger setting of the Norwegian continental margin with the old passive margin in the South Atlantic. In particular, the South Atlantic is interesting since the southern half

  2. Compilation of woody species occurring in the Brazilian Atlantic Forest complex

    Directory of Open Access Journals (Sweden)

    Rodrigo Scarton Bergamin

    2015-07-01

    Full Text Available The Atlantic Forest is a hotspot for biodiversity conservation because of its high levels of endemism and threatened areas. Three main forest types, differentiated by their floras, compose the Atlantic Forest: ‘Atlantic Forest’ sensu strictu, ‘Araucaria Mixed Forest’ and ‘Seasonal Forest’. The flora comprises taxa from the Amazon forest, Cerrado gallery forests and the Andean region, which makes the Atlantic Forest a relevant study system for ecologists and biogeographers. Here, we present data from 206 floris- tic checklists describing the occurrence of 1,916 species across the southern portion of the Atlantic Forest. This dataset can be useful for understanding mechanisms underlying plant community assembly processes and the historical relationships between different forest formations.

  3. Modeling the impact of changes in Atlantic sea surface temperature on the climate of West Africa

    Science.gov (United States)

    Adeniyi, Mojisola O.

    2016-08-01

    This study assesses the impacts of warming/cooling of the Atlantic sea surface temperature (SST) on the climate of West Africa using Version 4.4 of Regional Climate Model (RegCM4.4) of International Center for Theoretical Physics, Trieste, Italy. The 1-2 K cooling and warming of the Atlantic SST both result in tripole temperature and precipitation change structure, having a northwest-southeast orientation over West Africa. Findings reveal that the responses of precipitation and temperature to the Atlantic SST cooling are opposite to those for the Atlantic SST warming and these responses intensify with increased warming/cooling of the Atlantic SST. The structure of the change in climate is attributed to the response of atmospheric/soil moisture gradient and orientation of orography in West Africa.

  4. Surface changes in the North Atlantic meridional overturning circulation during the last millennium.

    Science.gov (United States)

    Wanamaker, Alan D; Butler, Paul G; Scourse, James D; Heinemeier, Jan; Eiríksson, Jón; Knudsen, Karen Luise; Richardson, Christopher A

    2012-01-01

    Despite numerous investigations, the dynamical origins of the Medieval Climate Anomaly and the Little Ice Age remain uncertain. A major unresolved issue relating to internal climate dynamics is the mode and tempo of Atlantic meridional overturning circulation variability, and the significance of decadal-to-centennial scale changes in Atlantic meridional overturning circulation strength in regulating the climate of the last millennium. Here we use the time-constrained high-resolution local radiocarbon reservoir age offset derived from an absolutely dated annually resolved shell chronology spanning the past 1,350 years, to reconstruct changes in surface ocean circulation and climate. The water mass tracer data presented here from the North Icelandic shelf, combined with previously published data from the Arctic and subtropical Atlantic, show that surface Atlantic meridional overturning circulation dynamics likely amplified the relatively warm conditions during the Medieval Climate Anomaly and the relatively cool conditions during the Little Ice Age within the North Atlantic sector. PMID:22692542

  5. North Atlantic warming: patterns of long-term trend and multidecadal variability

    Energy Technology Data Exchange (ETDEWEB)

    Polyakov, Igor V.; Alexeev, Vladimir A.; Zhang, Xiangdong [University of Alaska Fairbanks, International Arctic Research Center, Fairbanks, AK (United States); Bhatt, Uma S. [University of Alaska Fairbanks, Geophysical Institute, Fairbanks, AK (United States); Polyakova, Evgenia I. [Stanford University, Department of Geological and Environmental Studies, Stanford, CA (United States)

    2010-02-15

    Climate fluctuations in the North Atlantic Ocean have wide-spread implications for Europe, Africa, and the Americas. This study assesses the relative contribution of the long-term trend and variability of North Atlantic warming using EOF analysis of deep-ocean and near-surface observations. Our analysis demonstrates that the recent warming over the North Atlantic is linked to both long-term (including anthropogenic and natural) climate change and multidecadal variability (MDV, {proportional_to}50-80 years). Our results suggest a general warming trend of 0.031 {+-} 0.006 C/decade in the upper 2,000 m North Atlantic over the last 80 years of the twentieth century, although during this time there are periods in which short-term trends were strongly amplified by MDV. For example, MDV accounts for {proportional_to}60% of North Atlantic warming since 1970. The single-sign basin-scale pattern of MDV with prolonged periods of warming (cooling) in the upper ocean layer and opposite tendency in the lower layer is evident from observations. This pattern is associated with a slowdown (enhancement) of the North Atlantic thermohaline overturning circulation during negative (positive) MDV phases. In contrast, the long-term trend exhibits warming in tropical and mid-latitude North Atlantic and a pattern of cooling in regions associated with major northward heat transports, consistent with a slowdown of the North Atlantic circulation as evident from observations and confirmed by selected modeling results. This localized cooling has been masked in recent decades by warming during the positive phase of MDV. Finally, since the North Atlantic Ocean plays a crucial role in establishing and regulating the global thermohaline circulation, the multidecadal fluctuations discussed here should be considered when assessing long-term climate change and variability, both in the North Atlantic and at global scales. (orig.)

  6. Estimating canopy fuel parameters for Atlantic Coastal Plain forest types.

    Energy Technology Data Exchange (ETDEWEB)

    Parresol, Bernard, R.

    2007-01-15

    Abstract It is necessary to quantify forest canopy characteristics to assess crown fire hazard, prioritize treatment areas, and design treatments to reduce crown fire potential. A number of fire behavior models such as FARSITE, FIRETEC, and NEXUS require as input four particular canopy fuel parameters: 1) canopy cover, 2) stand height, 3) crown base height, and 4) canopy bulk density. These canopy characteristics must be mapped across the landscape at high spatial resolution to accurately simulate crown fire. Currently no models exist to forecast these four canopy parameters for forests of the Atlantic Coastal Plain, a region that supports millions of acres of loblolly, longleaf, and slash pine forests as well as pine-broadleaf forests and mixed species broadleaf forests. Many forest cover types are recognized, too many to efficiently model. For expediency, forests of the Savannah River Site are categorized as belonging to 1 of 7 broad forest type groups, based on composition: 1) loblolly pine, 2) longleaf pine, 3) slash pine, 4) pine-hardwood, 5) hardwood-pine, 6) hardwoods, and 7) cypress-tupelo. These 7 broad forest types typify forests of the Atlantic Coastal Plain region, from Maryland to Florida.

  7. Reevaluation of mid-Pliocene North Atlantic sea surface temperatures

    Science.gov (United States)

    Robinson, Marci M.; Dowsett, Harry J.; Dwyer, Gary S.; Lawrence, Kira T.

    2008-01-01

    Multiproxy temperature estimation requires careful attention to biological, chemical, physical, temporal, and calibration differences of each proxy and paleothermometry method. We evaluated mid-Pliocene sea surface temperature (SST) estimates from multiple proxies at Deep Sea Drilling Project Holes 552A, 609B, 607, and 606, transecting the North Atlantic Drift. SST estimates derived from faunal assemblages, foraminifer Mg/Ca, and alkenone unsaturation indices showed strong agreement at Holes 552A, 607, and 606 once differences in calibration, depth, and seasonality were addressed. Abundant extinct species and/or an unrecognized productivity signal in the faunal assemblage at Hole 609B resulted in exaggerated faunal-based SST estimates but did not affect alkenone-derived or Mg/Ca–derived estimates. Multiproxy mid-Pliocene North Atlantic SST estimates corroborate previous studies documenting high-latitude mid-Pliocene warmth and refine previous faunal-based estimates affected by environmental factors other than temperature. Multiproxy investigations will aid SST estimation in high-latitude areas sensitive to climate change and currently underrepresented in SST reconstructions.

  8. Equatorial segment of the mid-atlantic ridge

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    The Equatorial Segment of the Mid-Atlantic Ridge is a part of this mid-oceanic ridge limited by a cluster of fracture zones - Cape Verde, Marathon, Mercury, Vema, Doldrums, Vernadsky and Sierra Leone - in the North, and a similar cluster of fracture zones - St Paul, Romanche and Chain - in the South. During recent decades, following the publication of the 5. edition of the General Bathymetric Chart of the Oceans (GEBCO), there has been a great deal of geological-geophysical research and mapping of the World Ocean. The results have led to the development of a number of theories concerning the essential heterogeneity of the structure of the ocean floor and, in particular, the heterogeneity of the structure and segmentation of mid-oceanic ridges. Research on the nature of such segmentation is of great importance for an understanding of the processes of development of such ridges and oceanic basins as a whole. Chapter 20 is dedicated to the study of the atlantic ocean mantle by using (Th.U)Th, (Th/U)pb and K/Ti systematics 380 refs.

  9. Gene expression profiling of soft and firm Atlantic salmon fillet.

    Directory of Open Access Journals (Sweden)

    Thomas Larsson

    Full Text Available Texture of salmon fillets is an important quality trait for consumer acceptance as well as for the suitability for processing. In the present work we measured fillet firmness in a population of farmed Atlantic salmon with known pedigree and investigated the relationship between this trait and gene expression. Transcriptomic analyses performed with a 21 K oligonucleotide microarray revealed strong correlations between firmness and a large number of genes. Highly similar expression profiles were observed in several functional groups. Positive regression was found between firmness and genes encoding proteasome components (41 genes and mitochondrial proteins (129 genes, proteins involved in stress responses (12 genes, and lipid metabolism (30 genes. Coefficients of determination (R(2 were in the range of 0.64-0.74. A weaker though highly significant negative regression was seen in sugar metabolism (26 genes, R(2 = 0.66 and myofiber proteins (42 genes, R(2 = 0.54. Among individual genes that showed a strong association with firmness, there were extracellular matrix proteins (negative correlation, immune genes, and intracellular proteases (positive correlation. Several genes can be regarded as candidate markers of flesh quality (coiled-coil transcriptional coactivator b, AMP deaminase 3, and oligopeptide transporter 15 though their functional roles are unclear. To conclude, fillet firmness of Atlantic salmon depends largely on metabolic properties of the skeletal muscle; where aerobic metabolism using lipids as fuel, and the rapid removal of damaged proteins, appear to play a major role.

  10. Decadal Trends of Atlantic Basin Tropical Cyclones (1950-1999)

    Science.gov (United States)

    Wilson, Robert M.

    2001-01-01

    Ten-year moving averages of the seasonal rates for 'named storms,' tropical storms, hurricanes, and major (or intense) hurricanes in the Atlantic basin suggest that the present epoch is one of enhanced activity, marked by seasonal rates typically equal to or above respective long-term median rates. As an example, the 10-year moving average of the seasonal rates for named storms is now higher than for any previous year over the past 50 years, measuring 10.65 in 1994, or 2.65 units higher than its median rate of 8. Also, the 10-year moving average for tropical storms has more than doubled, from 2.15 in 1955 to 4.60 in 1992, with 16 of the past 20 years having a seasonal rate of three or more (the median rate). For hurricanes and major hurricanes, their respective 10-year moving averages turned upward, rising above long-term median rates (5.5 and 2, respectively) in 1992, a response to the abrupt increase in seasonal rates that occurred in 1995. Taken together, the outlook for future hurricane seasons is for all categories of Atlantic basin tropical cyclones to have seasonal rates at levels equal to or above long-term median rates, especially during non-El Nino-related seasons. Only during El Nino-related seasons does it appear likely that seasonal rates might be slightly diminished.

  11. An objective criterion for determining the South Atlantic Convergence Zone

    Directory of Open Access Journals (Sweden)

    Tercio eAmbrizzi

    2015-04-01

    Full Text Available The South Atlantic Convergence Zone (SACZ is the dominant summertime cloudiness feature of subtropical South America and the western South Atlantic Ocean, having a significant influence on the precipitation regime of southeastern Brazil. This paper proposes an objective criterion based mainly on precipitation, as this variable is easily obtained on general circulation models simulating past, present and future climate. Usually most SACZ studies use emerging long wave radiation as a precipitation proxy. This is enough to describe event position at first, but using precipitation would allow for better quantification, especially for climate studies, where precipitation is indispensable. An assessment was carried out to find out if classical DJF period is ideal for determining the SACZ for the present climate and future scenarios. In general the SACZ event detection criterion showed quite satisfactory results when event dates were previously known. When it was applied to future climate scenario it identified a number of events compatible with the present climate. The SACZ was well defined for both the simulated and observed precipitation data.

  12. Holocene shifts of the southern westerlies across the South Atlantic

    Science.gov (United States)

    Voigt, Ines; Chiessi, Cristiano M.; Prange, Matthias; Mulitza, Stefan; Groeneveld, Jeroen; Varma, Vidya; Henrich, Ruediger

    2015-02-01

    The southern westerly winds (SWW) exert a crucial influence over the world ocean and climate. Nevertheless, a comprehensive understanding of the Holocene temporal and spatial evolution of the SWW remains a significant challenge due to the sparsity of high-resolution marine archives and appropriate SWW proxies. Here we present a north-south transect of high-resolution planktonic foraminiferal oxygen isotope records from the western South Atlantic. Our proxy records reveal Holocene migrations of the Brazil-Malvinas Confluence (BMC), a highly sensitive feature for changes in the position and strength of the northern portion of the SWW. Through the tight coupling of the BMC position to the large-scale wind field, the records allow a quantitative reconstruction of Holocene latitudinal displacements of the SWW across the South Atlantic. Our data reveal a gradual poleward movement of the SWW by about 1-1.5° from the early to the mid-Holocene. Afterward, variability in the SWW is dominated by millennial scale displacements on the order of 1° in latitude with no recognizable longer-term trend. These findings are confronted with results from a state-of-the-art transient Holocene climate simulation using a comprehensive coupled atmosphere-ocean general circulation model. Proxy-inferred and modeled SWW shifts compare qualitatively, but the model underestimates both orbitally forced multimillennial and internal millennial SWW variability by almost an order of magnitude. The underestimated natural variability implies a substantial uncertainty in model projections of future SWW shifts.

  13. Socially segregated, sympatric sperm whale clans in the Atlantic Ocean

    Science.gov (United States)

    Bøttcher, Anne; Whitehead, Hal

    2016-01-01

    Sperm whales (Physeter macrocephalus) are unusual in that there is good evidence for sympatric populations with distinct culturally determined behaviour, including potential acoustic markers of the population division. In the Pacific, socially segregated, vocal clans with distinct dialects coexist; by contrast, geographical variation in vocal repertoire in the Atlantic has been attributed to drift. We examine networks of acoustic repertoire similarity and social interactions for 11 social units in the Eastern Caribbean. We find the presence of two socially segregated, sympatric vocal clans whose dialects differ significantly both in terms of categorical coda types produced by each clan (Mantel test between clans: matrix correlation = 0.256; p ≤ 0.001) and when using classification-free similarity which ignores defined types (Mantel test between clans: matrix correlation = 0.180; p ≤ 0.001). The more common of the two clans makes a characteristic 1 + 1 + 3 coda, while the other less often sighted clan makes predominantly regular codas. Units were only observed associating with other units within their vocal clan. This study demonstrates that sympatric vocal clans do exist in the Atlantic, that they define a higher order level of social organization as they do in the Pacific, and suggests that cultural identity at the clan level is probably important in this species worldwide. PMID:27429766

  14. Contourites and their Neogene Development along the NE Atlantic Margin

    Science.gov (United States)

    van Weering, T. C. E.; de Haas, H.; Shannon, P.; Praeg, D.; Stoker, M.; Holmes, R.

    2003-04-01

    During the EU funded STRATAGEM* program a new and unified Neogene stratigraphy of the NE Atlantic Margin from Ireland to north Norway was defined on the basis of analysis of a large suite of single and multi-channel profiles collected over the last decade by the STRATAGEM partners, complemented with partially confidential industry seismic and borehole data. Key reflectors were defined and by means of construction of stratigraphic range charts, constrained and tested by existing borehole and well data. These show that especially in the Rockall Trough and Faeroe Shetland Channel, and to a lesser extent off the Norwegian margin, contourite deposits form an important element of the Neogene succession. Onset of contourite development in the Rockall Trough and Porcupine Basin was in the early Oligocene, forced by rapid differential subsidence and seaward tilting of the basins. The contourites are predominantly developed along the basin margins and show in areas of upslope accretion, migration from the deep basin onto the slope with both onlapping and downlapping reflector terminations. The distribution and characteristics of the Neogene contourite development along the NE Atlantic margin will be defined in detail, in relation to tectonic and oceanographic conditions and their variability. *STRATAGEM www.stratagem-europe.org

  15. Blue whale (Balaenoptera musculus) sounds from the North Atlantic

    Science.gov (United States)

    Mellinger, David K.; Clark, Christopher W.

    2003-08-01

    Sounds of blue whales were recorded from U.S. Navy hydrophone arrays in the North Atlantic. The most common signals were long, patterned sequences of very-low-frequency sounds in the 15-20 Hz band. Sounds within a sequence were hierarchically organized into phrases consisting of one or two different sound types. Sequences were typically composed of two-part phrases repeated every 73 s: a constant-frequency tonal ``A'' part lasting approximately 8 s, followed 5 s later by a frequency-modulated ``B'' part lasting approximately 11 s. A common sequence variant consisted only of repetitions of part A. Sequences were separated by silent periods averaging just over four minutes. Two other sound types are described: a 2-5 s tone at 9 Hz, and a 5-7s inflected tone that swept up in frequency to ca. 70 Hz and then rapidly down to 25 Hz. The general characteristics of repeated sequences of simple combinations of long-duration, very-low-frequency sound units repeated every 1-2 min are typical of blue whale sounds recorded in other parts of the world. However, the specific frequency, duration, and repetition interval features of these North Atlantic sounds are different than those reported from other regions, lending further support to the notion that geographically separate blue whale populations have distinctive acoustic displays.

  16. Adaptive divergence in embryonic thermal plasticity among Atlantic salmon populations.

    Science.gov (United States)

    Côte, J; Roussel, J-M; Le Cam, S; Guillaume, F; Evanno, G

    2016-08-01

    In the context of global changes, the long-term viability of populations of endangered ectotherms may depend on their adaptive potential and ability to cope with temperature variations. We measured responses of Atlantic salmon embryos from four populations to temperature variations and used a QST -FST approach to study the adaptive divergence among these populations. Embryos were reared under two experimental conditions: a low temperature regime at 4 °C until eyed-stage and 10 °C until the end of embryonic development and a high temperature regime with a constant temperature of 10 °C throughout embryonic development. Significant variations among populations and population × temperature interactions were observed for embryo survival, incubation time and length. QST was higher than FST in all but one comparison suggesting an important effect of divergent selection. QST was also higher under the high-temperature treatment than at low temperature for length and survival due to a higher variance among populations under the stressful warmer treatment. Interestingly, heritability was lower for survival under high temperature in relation to a lower additive genetic variance under that treatment. Overall, these results reveal an adaptive divergence in thermal plasticity in embryonic life stages of Atlantic salmon suggesting that salmon populations may differentially respond to temperature variations induced by climate change. These results also suggest that changes in temperature may alter not only the adaptive potential of natural populations but also the selection regimes among them. PMID:27177256

  17. An experimental study of the Atlantic variability on interdecadal timescales

    Directory of Open Access Journals (Sweden)

    M. Vincze

    2012-06-01

    Full Text Available A series of laboratory experiments has been carried out to model the basic dynamics of the multidecadal variability observed in North Atlantic sea surface temperature (SST records. According to the minimal numerical sector model introduced by te Raa and Dijkstra (2002, the three key components to excite such a low-frequency variability are rotation, meridional temperature gradient and additive thermal noise in the surface heat forcing. If these components are present, periodic perturbations of the overturning background flow are excited, leading to thermal Rossby mode like propagation of anomalous patches in the SST field. Our tabletop scale setup was built to capture this phenomenon, and to test whether the aforementioned three components are indeed sufficient to generate a low-frequency variability in the system. The results are compared to those of the numerical models, as well as to oceanic SST reanalysis records. To the best of our knowledge, the experiment described here is the very first to investigate the dynamics of the North Atlantic multidecadal variability in a laboratory-scale setup.

  18. Socially segregated, sympatric sperm whale clans in the Atlantic Ocean.

    Science.gov (United States)

    Gero, Shane; Bøttcher, Anne; Whitehead, Hal; Madsen, Peter Teglberg

    2016-06-01

    Sperm whales (Physeter macrocephalus) are unusual in that there is good evidence for sympatric populations with distinct culturally determined behaviour, including potential acoustic markers of the population division. In the Pacific, socially segregated, vocal clans with distinct dialects coexist; by contrast, geographical variation in vocal repertoire in the Atlantic has been attributed to drift. We examine networks of acoustic repertoire similarity and social interactions for 11 social units in the Eastern Caribbean. We find the presence of two socially segregated, sympatric vocal clans whose dialects differ significantly both in terms of categorical coda types produced by each clan (Mantel test between clans: matrix correlation = 0.256; p ≤ 0.001) and when using classification-free similarity which ignores defined types (Mantel test between clans: matrix correlation = 0.180; p ≤ 0.001). The more common of the two clans makes a characteristic 1 + 1 + 3 coda, while the other less often sighted clan makes predominantly regular codas. Units were only observed associating with other units within their vocal clan. This study demonstrates that sympatric vocal clans do exist in the Atlantic, that they define a higher order level of social organization as they do in the Pacific, and suggests that cultural identity at the clan level is probably important in this species worldwide. PMID:27429766

  19. Late Holocene Radiocarbon Variability in Northwest Atlantic Slope Waters

    Energy Technology Data Exchange (ETDEWEB)

    Sherwood, O; Edinger, E; Guilderson, T P; Ghaleb, B; Risk, M J; Scott, D B

    2008-08-15

    Deep-sea gorgonian corals secrete a 2-part skeleton of calcite, derived from dissolved inorganic carbon at depth, and gorgonin, derived from recently fixed and exported particulate organic matter. Radiocarbon contents of the calcite and gorgonin provide direct measures of seawater radiocarbon at depth and in the overlying surface waters, respectively. Using specimens collected from Northwest Atlantic slope waters, we generated radiocarbon records for surface and upper intermediate water layers spanning the pre- and post bomb-{sup 14}C eras. In Labrador Slope Water (LSW), convective mixing homogenizes the pre-bomb {Delta}{sup 14}C signature (-67 {+-} 4{per_thousand}) to at least 1000 m depth. Surface water bomb-{sup 14}C signals were lagged and damped (peaking at {approx} +45{per_thousand} in the early 1980s) relative to other regions of the northwest Atlantic, and intermediate water signals were damped further. Off southwest Nova Scotia, the vertical gradient in {Delta}{sup 14}C is much stronger. In surface water, pre-bomb {Delta}{sup 14}C averaged -75 {+-} 5{per_thousand}. At 250-475 m depth, prebomb {Delta}{sup 14}C oscillated quasi-decadally between -80 and -100{per_thousand}, likely reflecting interannual variability in the presence of Labrador Slope Water vs. Warm Slope Water (WSW). Finally, subfossil corals reveal no systematic changes in vertical {Delta}{sup 14}C gradients over the last 1200 years.

  20. Monitoring the North Atlantic using ocean colour data

    Science.gov (United States)

    Fuentes-Yaco, C.; Caverhill, C.; Maass, H.; Porter, C.; White, GN, III

    2016-04-01

    The Remote Sensing Unit (RSU) at the Bedford Institute of Oceanography (BIO) has been monitoring the North Atlantic using ocean colour products for decades. Optical sensors used include CZCS, POLDER, SeaWiFS, MODIS/Aqua and MERIS. The monitoring area is defined by the Atlantic Zone Monitoring Program (AZMP) but certain products extend into Arctic waters, and all-Canadian waters which include the Pacific coast. RSU provides Level 3 images for various products in several formats and a range of temporal and spatial resolutions. Basic statistics for pre-defined areas of interest are compiled for each product. Climatologies and anomaly maps are also routinely produced, and custom products are delivered by request. RSU is involved in the generation of Level 4 products, such as characterizing the phenology of spring and fall phytoplankton blooms, computing primary production, using ocean colour to aid in EBSA (Ecologically and Biologically Significant Area) definition and developing habitat suitability maps. Upcoming operational products include maps of diatom distribution, biogeochemical province boundaries, and products from sensors such as VIIRS (Visible Infrared Imaging Radiometer Suite), OLCI (Ocean Land Colour Instrument), and PACE (Pre-Aerosol, Clouds and ocean Ecosystem) hyperspectral microsatellite mission.