WorldWideScience

Sample records for ccmp452 west atlantic

  1. 76 FR 68314 - Special Local Regulations; Key West World Championship, Atlantic Ocean; Key West, FL

    Science.gov (United States)

    2011-11-04

    ...-AA08 Special Local Regulations; Key West World Championship, Atlantic Ocean; Key West, FL AGENCY: Coast... regulations on the waters of the Atlantic Ocean located southwest of Key West, Florida during the Key West... unless authorized by the Captain of the Port Key West or a designated representative. DATES: This rule is...

  2. West Africa's Atlantic humpback dolphin ( Sousa teuszii ): endemic ...

    African Journals Online (AJOL)

    Atlantic humpback dolphins (Sousa teuszii) are endemic to nearshore West African waters between Western Sahara and Angola. They are considered Vulnerable by the International Union for Conservation of Nature based on restricted geographic range, low abundance and apparent decline in recent decades. We review ...

  3. Statolith comparison of two south-west Atlantic Loliginid squid ...

    African Journals Online (AJOL)

    The statoliths of two South-West Atlantic loliginid squid, Loligo gahi and Loligo sanpaulensis, were studied to determine if they could be a useful tool for species differentiation. Allometric equations were employed to examine differences in statolith shape and growth. Statolith dimensions were standardized by total length ...

  4. The Distribution of Dissolved Iron in the West Atlantic Ocean

    Science.gov (United States)

    Rijkenberg, Micha J. A.; Middag, Rob; Laan, Patrick; Gerringa, Loes J. A.; van Aken, Hendrik M.; Schoemann, Véronique; de Jong, Jeroen T. M.; de Baar, Hein J. W.

    2014-01-01

    Iron (Fe) is an essential trace element for marine life. Extremely low Fe concentrations limit primary production and nitrogen fixation in large parts of the oceans and consequently influence ocean ecosystem functioning. The importance of Fe for ocean ecosystems makes Fe one of the core chemical trace elements in the international GEOTRACES program. Despite the recognized importance of Fe, our present knowledge of its supply and biogeochemical cycle has been limited by mostly fragmentary datasets. Here, we present highly accurate dissolved Fe (DFe) values measured at an unprecedented high intensity (1407 samples) along the longest full ocean depth transect (17500 kilometers) covering the entire western Atlantic Ocean. DFe measurements along this transect unveiled details about the supply and cycling of Fe. External sources of Fe identified included off-shelf and river supply, hydrothermal vents and aeolian dust. Nevertheless, vertical processes such as the recycling of Fe resulting from the remineralization of sinking organic matter and the removal of Fe by scavenging still dominated the distribution of DFe. In the northern West Atlantic Ocean, Fe recycling and lateral transport from the eastern tropical North Atlantic Oxygen Minimum Zone (OMZ) dominated the DFe-distribution. Finally, our measurements showed that the North Atlantic Deep Water (NADW), the major driver of the so-called ocean conveyor belt, contains excess DFe relative to phosphate after full biological utilization and is therefore an important source of Fe for biological production in the global ocean. PMID:24978190

  5. Response of the Water Cycle of West Africa and Atlantic to Radiative Forcing by Saharan Dust

    Science.gov (United States)

    Lau, K. M.; Kim, Kyu-Myong; Sud, Yogesh C.; Walker, Gregory L.

    2010-01-01

    The responses of the atmospheric water cycle and climate of West Africa and the Atlantic to radiative forcing of Saharan dust are studied using the NASA finite volume general circulation model (fvGCM), coupled to a mixed layer ocean. We find evidence in support of the "elevated heat pump" (EHP) mechanism that underlines the responses of the atmospheric water cycle to dust forcing as follow. During the boreal summer, as a result of large-scale atmospheric feed back triggered by absorbing dust aerosols, rainfall and cloudiness are enhanced over the West Africa/Easter Atlantic ITCZ, and suppressed over the West Atlantic and Caribbean. region. Shortwave radiation absorption by dust warms the atmosphere and cools the surface, while long wave has the opposite response. The elevated dust layer warms the air over Nest Africa and the eastern Atlantic. The condensation heating associated with the induced deep convection drives and maintains an anomalous large-scale east-west overturning circulation with rising motion over West Africa/eastern Atlantic, and sinking motion over the Caribbean region. The response also includes a strengthening of the West African monsoon, manifested in northward shift of the West Africa precipitation over land, increased low-level westerlies flow over West Africa at the southern edge of the dust layer, and a near surface energy fluxes, resulting in cooling of the Nest African land and the eastern Atlantic, and a warming in the West Atlantic and Caribbean. The EHP effect is most effective for moderate to highly absorbing dusts, and becomes minimized for reflecting dust with single scattering albedo at 0.95 or higher.

  6. 78 FR 33221 - Special Local Regulation; Annual Swim Around Key West, Atlantic Ocean and Gulf of Mexico; Key...

    Science.gov (United States)

    2013-06-04

    ... 1625-AA08 Special Local Regulation; Annual Swim Around Key West, Atlantic Ocean and Gulf of Mexico; Key... the island of Key West, Florida during the Annual Swim around Key West on June 8, 2013. The event... clockwise around the island of Key West, Florida. The special local regulation is necessary to provide for...

  7. A multi-model approach to the Atlantic Equatorial mode: impact on the West African monsoon

    Energy Technology Data Exchange (ETDEWEB)

    Losada, T.; Rodriguez-Fonseca, B. [Universidad Complutense de Madrid, Madrid (Spain); Janicot, S.; Gervois, S. [LOCEAN/IPSL, CNRS, Universite Pierre et Marie Curie, Paris (France); Chauvin, F. [GAME/CNRM, Meteo-France/CNRS, Toulouse (France); Ruti, P. [Progetto Speciale Clima Globale, Ente Nazionale per le NuoveTecnologie, Rome (Italy)

    2010-07-15

    This paper is focused on the West African anomalous precipitation response to an Atlantic Equatorial mode whose origin, development and damping resembles the observed one during the last decades of the XXth century. In the framework of the AMMA-EU project, this paper analyses the atmospheric response to the Equatorial mode using a multimodel approach with an ensemble of integrations from 4 AGCMs under a time varying Equatorial SST mode. The Guinean Gulf precipitation, which together with the Sahelian mode accounts for most of the summer West African rainfall variability, is highly coupled to this Equatorial Atlantic SST mode or Atlantic Nino. In a previous study, done with the same models under 1958-1997 observed prescribed SSTs, most of the models identify the Equatorial Atlantic SST mode as the one most related to the Guinean Gulf precipitation. The models response to the positive phase of equatorial Atlantic mode (warm SSTs) depicts a direct impact in the equatorial Atlantic, leading to a decrease of the local surface temperature gradient, weakening the West African Monsoon flow and the surface convergence over the Sahel. (orig.)

  8. The Dutch and the Portuguese in West Africa : empire building and Atlantic system (1580-1674)

    NARCIS (Netherlands)

    Ribeiro da Silva, Filipa Isabel

    2009-01-01

    This thesis examines in comparative perspective the Dutch and the Portuguese Atlantic empires in the 17th century, using West Africa as a case study. The book is divided into two parts. In Part I, we study how the conditions in the home countries influenced the building of the empires. Here we

  9. 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.

  10. Ecological regime shift drives declining growth rates of sea turtles throughout the West Atlantic

    Science.gov (United States)

    Bjorndal, Karen A.; Bolten, Alan B.; Chaloupka, Milani; Saba, Vincent S.; Bellini, Cláudio; Marcovaldi, Maria A.G.; Santos, Armando J.B.; Bortolon, Luis Felipe Wurdig; Meylan, Anne B.; Meylan, Peter A.; Gray, Jennifer; Hardy, Robert; Brost, Beth; Bresette, Michael; Gorham, Jonathan C.; Connett, Stephen; Crouchley, Barbara Van Sciver; Dawson, Mike; Hayes, Deborah; Diez, Carlos E.; van Dam, Robert P.; Willis, Sue; Nava, Mabel; Hart, Kristen M.; Cherkiss, Michael S.; Crowder, Andrew; Pollock, Clayton; Hillis-Starr, Zandy; Muñoz Tenería, Fernando A.; Herrera-Pavón, Roberto; Labrada-Martagón, Vanessa; Lorences, Armando; Negrete-Philippe, Ana; Lamont, Margaret M.; Foley, Allen M.; Bailey, Rhonda; Carthy, Raymond R.; Scarpino, Russell; McMichael, Erin; Provancha, Jane A.; Brooks, Annabelle; Jardim, Adriana; López-Mendilaharsu, Milagros; González-Paredes, Daniel; Estrades, Andrés; Fallabrino, Alejandro; Martínez-Souza, Gustavo; Vélez-Rubio, Gabriela M.; Boulon, Ralf H.; Collazo, Jaime; Wershoven, Robert; Hernández, Vicente Guzmán; Stringell, Thomas B.; Sanghera, Amdeep; Richardson, Peter B.; Broderick, Annette C.; Phillips, Quinton; Calosso, Marta C.; Claydon, John A.B.; Metz, Tasha L.; Gordon, Amanda L.; Landry, Andre M.; Shaver, Donna J.; Blumenthal, Janice; Collyer, Lucy; Godley, Brendan J.; McGowan, Andrew; Witt, Matthew J.; Campbell, Cathi L.; Lagueux, Cynthia J.; Bethel, Thomas L.; Kenyon, Lory

    2017-01-01

    Somatic growth is an integrated, individual-based response to environmental conditions, especially in ectotherms. Growth dynamics of large, mobile animals are particularly useful as bio-indicators of environmental change at regional scales. We assembled growth rate data from throughout the West Atlantic for green turtles, Chelonia mydas, which are long-lived, highly migratory, primarily herbivorous mega-consumers that may migrate over hundreds to thousands of kilometers. Our dataset, the largest ever compiled for sea turtles, has 9690 growth increments from 30 sites from Bermuda to Uruguay from 1973 to 2015. Using generalized additive mixed models, we evaluated covariates that could affect growth rates; body size, diet, and year have significant effects on growth. Growth increases in early years until 1999, then declines by 26% to 2015. The temporal (year) effect is of particular interest because two carnivorous species of sea turtles – hawksbills, Eretmochelys imbricata, and loggerheads, Caretta caretta – exhibited similar significant declines in growth rates starting in 1997 in the West Atlantic, based on previous studies. These synchronous declines in productivity among three sea turtle species across a trophic spectrum provide strong evidence that an ecological regime shift (ERS) in the Atlantic is driving growth dynamics. The ERS resulted from a synergy of the 1997/1998 El Niño Southern Oscillation (ENSO) – the strongest on record – combined with an unprecedented warming rate over the last two to three decades. Further support is provided by the strong correlations between annualized mean growth rates of green turtles and both sea surface temperatures (SST) in the West Atlantic for years of declining growth rates (r = -0.94) and the Multivariate ENSO Index (MEI) for all years (r = 0.74). Granger-causality analysis also supports the latter finding. We discuss multiple stressors that could reinforce and prolong the effect of the ERS. This study

  11. Ecological regime shift drives declining growth rates of sea turtles throughout the West Atlantic.

    Science.gov (United States)

    Bjorndal, Karen A; Bolten, Alan B; Chaloupka, Milani; Saba, Vincent S; Bellini, Cláudio; Marcovaldi, Maria A G; Santos, Armando J B; Bortolon, Luis Felipe Wurdig; Meylan, Anne B; Meylan, Peter A; Gray, Jennifer; Hardy, Robert; Brost, Beth; Bresette, Michael; Gorham, Jonathan C; Connett, Stephen; Crouchley, Barbara Van Sciver; Dawson, Mike; Hayes, Deborah; Diez, Carlos E; van Dam, Robert P; Willis, Sue; Nava, Mabel; Hart, Kristen M; Cherkiss, Michael S; Crowder, Andrew G; Pollock, Clayton; Hillis-Starr, Zandy; Muñoz Tenería, Fernando A; Herrera-Pavón, Roberto; Labrada-Martagón, Vanessa; Lorences, Armando; Negrete-Philippe, Ana; Lamont, Margaret M; Foley, Allen M; Bailey, Rhonda; Carthy, Raymond R; Scarpino, Russell; McMichael, Erin; Provancha, Jane A; Brooks, Annabelle; Jardim, Adriana; López-Mendilaharsu, Milagros; González-Paredes, Daniel; Estrades, Andrés; Fallabrino, Alejandro; Martínez-Souza, Gustavo; Vélez-Rubio, Gabriela M; Boulon, Ralf H; Collazo, Jaime A; Wershoven, Robert; Guzmán Hernández, Vicente; Stringell, Thomas B; Sanghera, Amdeep; Richardson, Peter B; Broderick, Annette C; Phillips, Quinton; Calosso, Marta; Claydon, John A B; Metz, Tasha L; Gordon, Amanda L; Landry, Andre M; Shaver, Donna J; Blumenthal, Janice; Collyer, Lucy; Godley, Brendan J; McGowan, Andrew; Witt, Matthew J; Campbell, Cathi L; Lagueux, Cynthia J; Bethel, Thomas L; Kenyon, Lory

    2017-11-01

    Somatic growth is an integrated, individual-based response to environmental conditions, especially in ectotherms. Growth dynamics of large, mobile animals are particularly useful as bio-indicators of environmental change at regional scales. We assembled growth rate data from throughout the West Atlantic for green turtles, Chelonia mydas, which are long-lived, highly migratory, primarily herbivorous mega-consumers that may migrate over hundreds to thousands of kilometers. Our dataset, the largest ever compiled for sea turtles, has 9690 growth increments from 30 sites from Bermuda to Uruguay from 1973 to 2015. Using generalized additive mixed models, we evaluated covariates that could affect growth rates; body size, diet, and year have significant effects on growth. Growth increases in early years until 1999, then declines by 26% to 2015. The temporal (year) effect is of particular interest because two carnivorous species of sea turtles-hawksbills, Eretmochelys imbricata, and loggerheads, Caretta caretta-exhibited similar significant declines in growth rates starting in 1997 in the West Atlantic, based on previous studies. These synchronous declines in productivity among three sea turtle species across a trophic spectrum provide strong evidence that an ecological regime shift (ERS) in the Atlantic is driving growth dynamics. The ERS resulted from a synergy of the 1997/1998 El Niño Southern Oscillation (ENSO)-the strongest on record-combined with an unprecedented warming rate over the last two to three decades. Further support is provided by the strong correlations between annualized mean growth rates of green turtles and both sea surface temperatures (SST) in the West Atlantic for years of declining growth rates (r = -.94) and the Multivariate ENSO Index (MEI) for all years (r = .74). Granger-causality analysis also supports the latter finding. We discuss multiple stressors that could reinforce and prolong the effect of the ERS. This study demonstrates the

  12. Somatic growth dynamics of West Atlantic hawksbill sea turtles: a spatio-temporal perspective

    Science.gov (United States)

    Bjorndal, Karen A.; Chaloupka, Milani; Saba, Vincent S.; Diez, Carlos E.; van Dam, Robert P.; Krueger, Barry H.; Horrocks, Julia A.; Santos, Armando J.B.; Bellini, Cláudio; Marcovaldi, Maria A.G.; Nava, Mabel; Willis, Sue; Godley, Brendan J.; Gore, Shannon; Hawkes, Lucy A.; McGowan, Andrew; Witt, Matthew J.; Stringell, Thomas B.; Sanghera, Amdeep; Richardson, Peter B.; Broderick, Annette C.; Phillips, Quinton; Calosso, Marta C.; Claydon, John A.B.; Blumenthal, Janice; Moncada, Felix; Nodarse, Gonzalo; Medina, Yosvani; Dunbar, Stephen G.; Wood, Lawrence D.; Lagueux, Cynthia J.; Campbell, Cathi L.; Meylan, Anne B.; Meylan, Peter A.; Burns Perez, Virginia R.; Coleman, Robin A.; Strindberg, Samantha; Guzmán-H, Vicente; Hart, Kristen M.; Cherkiss, Michael S.; Hillis-Starr, Zandy; Lundgren, Ian; Boulon, Ralf H.; Connett, Stephen; Outerbridge, Mark E.; Bolten, Alan B.

    2016-01-01

    Somatic growth dynamics are an integrated response to environmental conditions. Hawksbill sea turtles (Eretmochelys imbricata) are long-lived, major consumers in coral reef habitats that move over broad geographic areas (hundreds to thousands of kilometers). We evaluated spatio-temporal effects on hawksbill growth dynamics over a 33-yr period and 24 study sites throughout the West Atlantic and explored relationships between growth dynamics and climate indices. We compiled the largest ever data set on somatic growth rates for hawksbills – 3541 growth increments from 1980 to 2013. Using generalized additive mixed model analyses, we evaluated 10 covariates, including spatial and temporal variation, that could affect growth rates. Growth rates throughout the region responded similarly over space and time. The lack of a spatial effect or spatio-temporal interaction and the very strong temporal effect reveal that growth rates in West Atlantic hawksbills are likely driven by region-wide forces. Between 1997 and 2013, mean growth rates declined significantly and steadily by 18%. Regional climate indices have significant relationships with annual growth rates with 0- or 1-yr lags: positive with the Multivariate El Niño Southern Oscillation Index (correlation = 0.99) and negative with Caribbean sea surface temperature (correlation = −0.85). Declines in growth rates between 1997 and 2013 throughout the West Atlantic most likely resulted from warming waters through indirect negative effects on foraging resources of hawksbills. These climatic influences are complex. With increasing temperatures, trajectories of decline of coral cover and availability in reef habitats of major prey species of hawksbills are not parallel. Knowledge of how choice of foraging habitats, prey selection, and prey abundance are affected by warming water temperatures is needed to understand how climate change will affect productivity of consumers that live in association with coral reefs. Main

  13. Tropical Atlantic Hurricanes, Easterly Waves, and West African Mesoscale Convective Systems

    Directory of Open Access Journals (Sweden)

    Yves K. Kouadio

    2010-01-01

    Full Text Available The relationship between tropical Atlantic hurricanes (Hs, atmospheric easterly waves (AEWs, and West African mesoscale convective systems (MCSs is investigated. It points out atmospheric conditions over West Africa before hurricane formation. The analysis was performed for two periods, June–November in 2004 and 2005, during which 12 hurricanes (seven in 2004, five in 2005 were selected. Using the AEW signature in the 700 hPa vorticity, a backward trajectory was performed to the African coast, starting from the date and position of each hurricane, when and where it was catalogued as a tropical depression. At this step, using the Meteosat-7 satellite dataset, we selected all the MCSs around this time and region, and tracked them from their initiation until their dissipation. This procedure allowed us to relate each of the selected Hs with AEWs and a succession of MCSs that occurred a few times over West Africa before initiation of the hurricane. Finally, a dipole in sea surface temperature (SST was observed with a positive SST anomaly within the region of H generation and a negative SST anomaly within the Gulf of Guinea. This SST anomaly dipole could contribute to enhance the continental convergence associated with the monsoon that impacts on the West African MCSs formation.

  14. Deglacial Tropical Atlantic subsurface warming links ocean circulation variability to the West African Monsoon.

    Science.gov (United States)

    Schmidt, Matthew W; Chang, Ping; Parker, Andrew O; Ji, Link; He, Feng

    2017-11-13

    Multiple lines of evidence show that cold stadials in the North Atlantic were accompanied by both reductions in Atlantic Meridional Overturning Circulation (AMOC) and collapses of the West African Monsoon (WAM). Although records of terrestrial change identify abrupt WAM variability across the deglaciation, few studies show how ocean temperatures evolved across the deglaciation. To identify the mechanism linking AMOC to the WAM, we generated a new record of subsurface temperature variability over the last 21 kyr based on Mg/Ca ratios in a sub-thermocline dwelling planktonic foraminifera in an Eastern Equatorial Atlantic (EEA) sediment core from the Niger Delta. Our subsurface temperature record shows abrupt subsurface warming during both the Younger Dryas (YD) and Heinrich Event 1. We also conducted a new transient coupled ocean-atmosphere model simulation across the YD that better resolves the western boundary current dynamics and find a strong negative correlation between AMOC strength and EEA subsurface temperatures caused by changes in ocean circulation and rainfall responses that are consistent with the observed WAM change. Our combined proxy and modeling results provide the first evidence that an oceanic teleconnection between AMOC strength and subsurface temperature in the EEA impacted the intensity of the WAM on millennial time scales.

  15. A GCM study of the response of the atmospheric water cycle of West Africa and the Atlantic to Saharan dust radiative forcing

    Directory of Open Access Journals (Sweden)

    K. M. Lau

    2009-10-01

    Full Text Available The responses of the atmospheric water cycle and climate of West Africa and the Atlantic to radiative forcing of Saharan dust are studied using the NASA finite volume general circulation model (fvGCM, coupled to a mixed layer ocean. We find evidence of an "elevated heat pump" (EHP mechanism that underlines the responses of the atmospheric water cycle to dust forcing as follow. During the boreal summer, as a result of large-scale atmospheric feedback triggered by absorbing dust aerosols, rainfall and cloudiness are enhanced over the West Africa/Eastern Atlantic ITCZ, and suppressed over the West Atlantic and Caribbean region. Shortwave radiation absorption by dust warms the atmosphere and cools the surface, while longwave has the opposite response. The elevated dust layer warms the air over West Africa and the eastern Atlantic. As the warm air rises, it spawns a large-scale onshore flow carrying the moist air from the eastern Atlantic and the Gulf of Guinea. The onshore flow in turn enhances the deep convection over West Africa land, and the eastern Atlantic. The condensation heating associated with the ensuing deep convection drives and maintains an anomalous large-scale east-west overturning circulation with rising motion over West Africa/eastern Atlantic, and sinking motion over the Caribbean region. The response also includes a strengthening of the West African monsoon, manifested in a northward shift of the West Africa precipitation over land, increased low-level westerly flow over West Africa at the southern edge of the dust layer, and a near surface westerly jet underneath the dust layer over the Sahara. The dust radiative forcing also leads to significant changes in surface energy fluxes, resulting in cooling of the West African land and the eastern Atlantic, and warming in the West Atlantic and Caribbean. The EHP effect is most effective for moderate to highly absorbing dusts, and becomes minimized for reflecting dust with single

  16. A GCM Study of Responses of the Atmospheric Water Cycle of West Africa and the Atlantic to Saharan Dust Radiative Forcing

    Science.gov (United States)

    Lau, K. M.; Kim, K. M.; Sud, Y. C.; Walker, G. K.

    2009-01-01

    The responses of the atmospheric water cycle and climate of West Africa and the Atlantic to radiative forcing of Saharan dust are studied using the NASA finite volume general circulation model (fvGCM), coupled to a mixed layer ocean. We find evidence of an "elevated heat pump" (EHP) mechanism that underlines the responses of the atmospheric water cycle to dust forcing as follow. During the boreal summerr, as a result of large-scale atmospheric feedback triggered by absorbing dust aerosols, rainfall and cloudiness are ehanIed over the West Africa/Eastern Atlantic ITCZ, and suppressed over the West Atlantic and Caribbean region. Shortwave radiation absorption by dust warms the atmosphere and cools the surface, while longwave has the opposite response. The elevated dust layer warms the air over West Africa and the eastern Atlantic. As the warm air rises, it spawns a large-scale onshore flow carrying the moist air from the eastern Atlantic and the Gulf of Guinea. The onshore flow in turn enhances the deep convection over West Africa land, and the eastern Atlantic. The condensation heating associated with the ensuing deep convection drives and maintains an anomalous large-scale east-west overturning circulation with rising motion over West Africa/eastern Atlantic, and sinking motion over the Caribbean region. The response also includes a strengthening of the West African monsoon, manifested in a northward shift of the West Africa precipitation over land, increased low-level westerlies flow over West Africa at the southern edge of the dust layer, and a near surface westerly jet underneath the dust layer overr the Sahara. The dust radiative forcing also leads to significant changes in surface energy fluxes, resulting in cooling of the West African land and the eastern Atlantic, and warming in the West Atlantic and Caribbean. The EHP effect is most effective for moderate to highly absorbing dusts, and becomes minimized for reflecting dust with single scattering albedo at0

  17. Recent uplift of the Atlantic Atlas (offshore West Morocco): Tectonic arch and submarine terraces

    Science.gov (United States)

    Benabdellouahed, M.; Klingelhoefer, F.; Gutscher, M.-A.; Rabineau, M.; Biari, Y.; Hafid, M.; Duarte, J. C.; Schnabel, M.; Baltzer, A.; Pedoja, K.; Le Roy, P.; Reichert, C.; Sahabi, M.

    2017-06-01

    Re-examination of marine geophysical data from the continental margin of West Morocco reveals a broad zone characterized by deformation, active faults and updoming offshore the High Atlas (Morocco margin), situated next to the Tafelney Plateau. Both seismic reflection and swath-bathymetric data, acquired during Mirror marine geophysical survey in 2011, indicate recent uplift of the margin including uplift of the basement. This deformation, which we propose to name the Atlantic Atlas tectonic arch, is interpreted to result largely through uplift of the basement, which originated during the Central Atlantic rifting stage - or even during phases of Hercynian deformation. This has produced a large number of closely spaced normal and reverse faults, ;piano key faults;, originating from the basement and affecting the entire sedimentary sequence, as well as the seafloor. The presence of four terraces in the Essaouira canyon system at about 3500 meters water depth and ;piano key faults; and the fact that these also affect the seafloor, indicate that the Atlantic Atlas is still active north of Agadir canyon. We propose that recent uplift is causing morphogenesis of four terraces in the Essaouira canyon system. In this paper the role of both Canary plume migration and ongoing convergence between the African and Eurasian plates in the formation of the Atlantic Atlas are discussed as possibilities to explain the presence of a tectonic arch in the region. The process of reactivation of passive margins is still not well understood. The region north of Agadir canyon represents a key area to better understand this process.

  18. Manganese in the west Atlantic Ocean in the context of the first global ocean circulation model of manganese

    NARCIS (Netherlands)

    van Hulten, Marco; Middag, Rob; Dutay, Jean-Claude; de Baar, Hein; Roy-Barman, Matthieu; Gehlen, Marion; Tagliabue, Alessandro; Sterl, Andreas

    2017-01-01

    Dissolved manganese (Mn) is a biologically essential element. Moreover, its oxidised form is involved in removing itself and several other trace elements from ocean waters. Here we report the longest thus far (17 500 km length) full-depth ocean section of dissolved Mn in the west Atlantic Ocean,

  19. NOAA/West coast and Alaska Tsunami warning center Atlantic Ocean response criteria

    Science.gov (United States)

    Whitmore, P.; Refidaff, C.; Caropolo, M.; Huerfano-Moreno, V.; Knight, W.; Sammler, W.; Sandrik, A.

    2009-01-01

    West Coast/Alaska Tsunami Warning Center (WCATWC) response criteria for earthquakesoccurring in the Atlantic and Caribbean basins are presented. Initial warning center decisions are based on an earthquake's location, magnitude, depth, distance from coastal locations, and precomputed threat estimates based on tsunami models computed from similar events. The new criteria will help limit the geographical extent of warnings and advisories to threatened regions, and complement the new operational tsunami product suite. Criteria are set for tsunamis generated by earthquakes, which are by far the main cause of tsunami generation (either directly through sea floor displacement or indirectly by triggering of sub-sea landslides).The new criteria require development of a threat data base which sets warning or advisory zones based on location, magnitude, and pre-computed tsunami models. The models determine coastal tsunami amplitudes based on likely tsunami source parameters for a given event. Based on the computed amplitude, warning and advisory zones are pre-set.

  20. Occurrence of anisakid nematodes in Atlantic cod (Gadus morhua) and Greenland cod (Gadus ogac), West Greenland

    DEFF Research Database (Denmark)

    Mouritsen, Kim N.; Hedeholm, Rasmus; Schack, Henriette B.

    2010-01-01

    Anisakid nematodes commonly infect gadids, and are of economic and aesthetic importance to the commercial fishing industry in Greenland as some species are pathogenic to humans. However, very little is known about the occurrence of these parasites and their impact on the hosts in Greenland waters....... During a survey in 2005, stomach sample of 227 Atlantic cod (Gadus morhua) and 64 Greenland cod (Gadus ogac) was collected in Godthaab and Sisimiut fiord systems in West Greenland waters. All cod were dissected for stomach contents and anisakid nematodes were removed from the visceral cavity. Third stage...... larvae (L3) of three anisakid species were found, including Contracaecum osculatum (Rudolphi, 1802), Anisakis simplex (Rudolphi, 1809) and Hysterothylacium aduncum (Rudolphi, 1802). Molecular identification by PCR-RFLP indicated the presence of A. simplex s.s. and the sibling species C. osculatum B and C...

  1. Assessing the link between Atlantic Niño 1 and drought over West Africa using CORDEX regional climate models

    Science.gov (United States)

    Adeniyi, Mojisola Oluwayemisi; Dilau, Kabiru Alabi

    2018-02-01

    The skill of Coordinated Regional Climate Downscaling Experiment (CORDEX) models (ARPEGE, CCLM, HIRHAM, RACMO, REMO, PRECIS, RegCM3, RCA, WRF and CRCM) in simulating the climate (precipitation, temperature and drought) of West Africa is determined using a process-based metric. This is done by comparing the CORDEX models' simulated and observed correlation coefficients between Atlantic Niño Index 1 (ATLN1) and the climate over West Africa. Strong positive correlation is observed between ATLN1 and the climate parameters at the Guinea Coast (GC). The Atlantic Ocean has Niño behaviours through the ATLN indices which influence the climate of the tropics. Drought has distinct dipole structure of correlation with ATLN1 (negative at the Sahel); precipitation does not have distinct dipole structure of correlation, while temperature has almost a monopole correlation structure with ATLN1 over West Africa. The magnitude of the correlation increases with closeness to the equatorial eastern Atlantic. Correlations between ATLN1 and temperature are mostly stronger than those between ATLN1 and precipitation over the region. Most models have good performance over the GC, but ARPEGE has the highest skill at GC. The PRECIS is the most skilful over Savannah and RCA over Sahel. These models can be used to downscale the projected climate at the region of their highest skill.

  2. Coupling of Wave and Circulation Models in the Atlantic European North-West Shelf Predicting System

    Science.gov (United States)

    Staneva, Joanna; Krüger, Oliver; Behrens, Arno; Lewis, Huw; Castillo, Juan M.

    2017-04-01

    This study addresses the coupling between wind wave and circulation models on the example of the Atlantic - European North-West Shelf (NWS). This topic reflects the increased interest in operational oceanography to reduce prediction errors of state estimates at coastal scales. The uncertainties in most of the presently used models result from the nonlinear feedback between strong tidal currents and wind-waves, which can no longer be ignored, in particular in the coastal zone where its role seems to be dominant. Coupled circulation (NEMO) and wave model (WAM) system was used to study the effects of surface ocean waves on thermohaline distribution and ocean circulation at the NWS. Four scenarios - including Stokes-Coriolis force, sea-state dependent energy flux (additional turbulent kinetic energy due to breaking waves), sea-state dependent momentum flux and the combination of the three wave-induced forcing were performed to study the role of the wave-induced processes on model simulations. The individual and collective role of those processes is quantified and the results are compared with the NWS circulation model results without wave effects as well as against various in-situ measurements. The performance of the forecasting system is illustrated for the cases of several extreme events. The improved skills resulting from the new developments in the forecasting system, in particular during extreme events, justify further enhancements of the coastal operational systems. The study is performed in the frame of the COPERNICUS CMEMS Service Evolution Projects Wave2NEMO and OWAIRS.

  3. Seasonal assemblages and short-lived blooms in coastal north-west Atlantic Ocean bacterioplankton.

    Science.gov (United States)

    El-Swais, Heba; Dunn, Katherine A; Bielawski, Joseph P; Li, William K W; Walsh, David A

    2015-10-01

    Temperate oceans are inhabited by diverse and temporally dynamic bacterioplankton communities. However, the role of the environment, resources and phytoplankton dynamics in shaping marine bacterioplankton communities at different time scales remains poorly constrained. Here, we combined time series observations (time scales of weeks to years) with molecular analysis of formalin-fixed samples from a coastal inlet of the north-west Atlantic Ocean to show that a combination of temperature, nitrate, small phytoplankton and Synechococcus abundances are best predictors for annual bacterioplankton community variability, explaining 38% of the variation. Using Bayesian mixed modelling, we identified assemblages of co-occurring bacteria associated with different seasonal periods, including the spring bloom (e.g. Polaribacter, Ulvibacter, Alteromonadales and ARCTIC96B-16) and the autumn bloom (e.g. OM42, OM25, OM38 and Arctic96A-1 clades of Alphaproteobacteria, and SAR86, OM60 and SAR92 clades of Gammaproteobacteria). Community variability over spring bloom development was best explained by silicate (32%)--an indication of rapid succession of bacterial taxa in response to diatom biomass--while nanophytoplankton as well as picophytoplankton abundance explained community variability (16-27%) over the transition into and out of the autumn bloom. Moreover, the seasonal structure was punctuated with short-lived blooms of rare bacteria including the KSA-1 clade of Sphingobacteria related to aromatic hydrocarbon-degrading bacteria. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

  4. Karst of the Mid-Atlantic region in Maryland, West Virginia, and Virginia

    Science.gov (United States)

    Doctor, Daniel H.; Weary, David J.; Brezinski, David K.; Orndorff, Randall C.; Spangler, Lawrence E.; Brezinski, David K.; Halka, Jeffrey; Ortt, Richard A.

    2015-01-01

    The Mid-Atlantic region hosts some of the most mature karst landscapes in North America, developed in highly deformed rocks within the Piedmont and Valley and Ridge physiographic provinces. This guide describes a three-day excursion to examine karst development in various carbonate rocks by following Interstate 70 west from Baltimore across the eastern Piedmont, across the Frederick Valley, and into the Great Valley proper. The localities were chosen in order to examine the structural and lithological controls on karst feature development in marble, limestone, and dolostone rocks with an eye toward the implications for ancient landscape evolution, as well as for modern subsidence hazards. A number of caves will be visited, including two commercial caverns that reveal strikingly different histories of speleogenesis. Links between karst landscape development, hydrologic dynamics, and water resource sustainability will also be emphasized through visits to locally important springs. Recent work on quantitative dye tracing, spring water geochemistry, and groundwater modeling reveal the interaction between shallow and deep circulation of groundwater that has given rise to the modern karst landscape. Geologic and karst feature mapping conducted with the benefit of lidar data help reveal the strong bedrock structural controls on karst feature development, and illustrate the utility of geologic maps for assessment of sinkhole susceptibility.

  5. Reproductive biology of the spotback skate Atlantoraja castelnaui in the south-west Atlantic Ocean.

    Science.gov (United States)

    Colonello, J C; García, M L; Lasta, C A; Menni, R C

    2012-06-01

    This study provides information on the reproduction of spotback skate Atlantoraja castelnaui. A total of 232 individuals (119 females and 113 males) were obtained from surveys carried out between 2003 and 2006, from the south-west Atlantic Ocean, between 34 and 42° S and <50 m deep; another 514 specimens (241 females and 273 males) were obtained between 2005 and 2007 from commercial fishery operations carried out in the same area and landings in the port of Mar del Plata, Argentina. Males ranged from 185 to 1250 mm total length (L(T) ) and females from 243 to 1368 mm L(T) . Length at maturity was estimated to be 980 mm for males and 1089 mm L(T) for females. Lack of variation of testis mass together with the continuous production of mature spermatocyst and spermatozoa in deferent ducts suggested that males can reproduce throughout the year. Females reproduced year-round with peaks of reproductive activity an integral part of a continuous cycle. This conclusion is corroborated by the seasonal variation of ovaries, oviducal gland and the occurrence of females with eggs in the uterus throughout the year. Results from this study indicate that A. castelnaui is very susceptible to fishery pressure. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

  6. Holocene Dunefield Construction, Wind Climate and North Atlantic Climate Change: Data From The West Coast of Jutland, Denmark

    Science.gov (United States)

    Clemmensen, L. B.

    Holocene dunefield construction on the west coast of Jutland (56 N) was episodic (Clemmensen et al., 2001a; 2001b). Evidence from optically stimulated luminescence dating and radiocarbon dating supplemented by archaeological data and historical ob- servations places the onset of these phases of increased aeolian activity to about 4000 BC, 2200 BC, 700 BC, AD 500, AD 1100, and AD 1625. Most of these aeolian events record increased storminess and were simultaneous with climatic cooling phases in the North Atlantic (Bond et al., 1997; Bianchi &McCave, 1999). During these events cool, ice-bearing waters were advected far southward in the North Atlantic Ocean and the atmospheric circulation changed (Bond et al., 1997). Climate model experiments suggest that during periods of increased sea-ice cover and cold waters in the North Atlantic Ocean the jet stream over the North Atlantic was strengthened, causing an enhanced cyclonic activity over large parts of Europe (Renssen et al., 1997; Lopez et al., 2000). These climatic events can probably be explained by a change in solar activity (van Geel et al., 1999). Thus geological data and climate experiments agree well and suggest millennial-scale variability in storminess in Jutland in concert with climatic change in the North Atlantic. References: Bianchi, G. G. &McCave, I. N., 1999: Holocene periodicity in North Atlantic climate and deep-ocean flow south of Iceland. Nature, 397, 515-517. Bond et al., 1997: A pervasive millennial-scale cycle in North Atlantic Holocene and glacial climates. Science, 278, 1257-1266. Clemmensen et al., 2001a: Sedimentology, stratigraphy and landscape evolution of a Holocene coastal dune system, Lodbjerg, NW Jutland, Denmark. Sedimentology,48, 3-27. Clemmensen et al., 2001b: A Holocene coastal aeolian system, Vejers, Denmark: land- scape evolution and sequence stratigraphy. Terra Nova, 13, 129-134.

  7. Combined effects of global warming and an Atlantic meridional overturning circulation shutdown on West African and European climate

    Science.gov (United States)

    Brown, M. G.; Vizy, E. K.; Cook, K. H.

    2011-12-01

    We investigate the effects of an Atlantic meridional overturning circulation (AMOC) shutdown, for example, due to an influx of fresh water from Arctic ice sheet melting, in combination with global warming (Intergovernmental Panel on Climate Change's A2 business as normal emissions scenario) on West African and European climate. Shutdown of the AMOC by the end of this century is generally seen as possible but not likely, but Arctic ice is melting more quickly than predicted by global models, and the consequences for climate may be severe and the changes abrupt. A regional climate model with 90-km grid spacing is used to conduct a series of present day and future AMOC shutdown simulations. The present-day control initial surface and lateral boundary conditions are derived from the present day National Center for Environmental Prediction reanalysis 2 (NCEP2). For the future runs we use coupled atmosphere-ocean GCM anomalies generated from the Intergovernmental Panel on Climate Change's Assessment Report 4 (IPCC AR4) A2 business as normal emission scenario experiment and apply them directly to the present day control boundary conditions. An idealized SSTA is derived and applied to the present day SSTs based upon coupled atmosphere/ocean GCM water hosing experiments that force a shutdown of the AMOC, but placed in the context of under global warming, In both the boreal spring and summer months, cooling in the eastern Atlantic due to the AMOC shutdown causes an eastward extension of the North Atlantic subtropical high over Europe and rainfall rates decrease markedly throughout most of Europe. In May and June, rainfall rates decrease by 50-80% over Sahelian Africa as a secondary response to the eastern Atlantic cool SSTs, as dry air is advected southward, associated with enhanced northerly flow. In contrast, the atmospheric response to the SSTA in the North Atlantic over Europe and West Africa is decoupled during the boreal summer months; rainfall over Europe continues to

  8. The Impact of the Atlantic Cold Tongue on West African Monsoon Onset in Regional Model Simulations for 1998-2002

    Science.gov (United States)

    Druyan, Leonard M.; Fulakeza, Matthew B.

    2014-01-01

    The Atlantic cold tongue (ACT) develops during spring and early summer near the Equator in the Eastern Atlantic Ocean and Gulf of Guinea. The hypothesis that the ACT accelerates the timing of West African monsoon (WAM) onset is tested by comparing two regional climate model (RM3) simulation ensembles. Observed sea surface temperatures (SST) that include the ACT are used to force a control ensemble. An idealized, warm SST perturbation is designed to represent lower boundary forcing without the ACT for the experiment ensemble. Summer simulations forced by observed SST and reanalysis boundary conditions for each of five consecutive years are compared to five parallel runs forced by SST with the warm perturbation. The article summarizes the sequence of events leading to the onset of the WAM in the Sahel region. The representation of WAM onset in RM3 simulations is examined and compared to Tropical Rainfall Measuring Mission (TRMM), Global Precipitation Climatology Project (GPCP) and reanalysis data. The study evaluates the sensitivity of WAM onset indicators to the presence of the ACT by analysing the differences between the two simulation ensembles. Results show that the timing of major rainfall events and therefore theWAM onset in the Sahel are not sensitive to the presence of the ACT. However, the warm SST perturbation does increase downstream rainfall rates over West Africa as a consequence of enhanced specific humidity and enhanced northward moisture flux in the lower troposphere.

  9. Future Changes in Cyclonic Wave Climate in the North Atlantic, with a Focus on the French West Indies

    Science.gov (United States)

    Belmadani, A.; Palany, P.; Dalphinet, A.; Pilon, R.; Chauvin, F.

    2017-12-01

    Tropical cyclones (TCs) are a major environmental hazard in numerous small islands such as the French West Indies (Guadeloupe, Martinique, St-Martin, St-Barthélémy). The intense associated winds, which can reach 300 km/h or more, can cause serious damage in the islands and their coastlines. In particular, the combined action of waves, currents and low atmospheric pressure leads to severe storm surge and coastal flooding. Here we report on future changes in cyclonic wave climate for the North Atlantic basin, as a preliminary step for downscaled projections over the French West Indies at sub-kilometer-scale resolution. A new configuration of the Météo-France ARPEGE atmospheric general circulation model on a stretched grid with increased resolution in the tropical North Atlantic ( 15 km) is able to reproduce the observed distribution of maximum surface winds, including extreme events corresponding to Category 5 hurricanes. Ensemble historical simulations (1985-2014, 5 members) and future projections with the IPCC (Intergovernmental Panel on Climate Change) RCP8.5 scenario (2051-2080, 5 members) are used to drive the MFWAM (Météo-France Wave Action Model) over the North Atlantic basin. A lower 50-km resolution grid is used to propagate distant mid-latitude swells into a higher 10-km resolution grid over the cyclonic basin. Wave model performance is evaluated over a few TC case studies including the Sep-Oct 2016 Category 5 Hurricane Matthew, using an operational version of ARPEGE at similar resolution to force MFWAM together with wave buoy data. The latter are also used to compute multi-year wave statistics, which then allow assessing the realism of the MFWAM historical runs. For each climate scenario and ensemble member, a simulation of the cyclonic season (July to mid-November) is performed every year. The simulated sea states over the North Atlantic cyclonic basin over 150 historical simulations are compared to their counterparts over 150 future simulations

  10. Dissolved aluminium in the ocean conveyor of the West Atlantic Ocean : Effects of the biological cycle, scavenging, sediment resuspension and hydrography

    NARCIS (Netherlands)

    Middag, R.; van Hulten, M. M. P.; Van Aken, H. M.; Rijkenberg, M. J. A.; Gerringa, L. J. A.; Laan, P.; de Baar, H. J. W.

    2015-01-01

    The concentrations of dissolved aluminium (dissolved Al) were studied along the West Atlantic GEOTRACES GA02 transect from 64 degrees N to 50 degrees S. Concentrations ranged from similar to 0.5 nmol kg(-1) in the high latitude surface waters to similar to 48 nmol kg(-1) in surface waters around 25

  11. The status of marine biodiversity in the Eastern Central Atlantic (West and Central Africa)

    DEFF Research Database (Denmark)

    Polidoro, Beth A.; Ralph, Gina M.; Strongin, Kyle

    2017-01-01

    The status of marine biodiversity in the Eastern Central Atlantic (ECA), especially of coastal and pelagic fishes, is of concern owing to a number of threats including overharvesting, habitat loss, pollution, and climate change combined with inadequate policy responses, legislation, and enforceme...

  12. Effect of Warm Atlantic Waters on the Climate Anomalies in the West Arctic

    Directory of Open Access Journals (Sweden)

    A. N. Zolotokrylin

    2015-01-01

    Full Text Available Significant climatic changes of oceanic and atmospheric elements and a relation of them to the ocean surface winter anomalies in North Atlantic are analyzed in the paper. Periods of «warm» ocean (2002–2012 and «cold» ocean (1960–1970 were determined. Positive anomalies of the ocean surface temperature increase the ice-free water area and, correspondingly, decrease the ice-field area. As a result of such changes in a state of the ocean surface (open water and ice, surface air temperature rises, and, consequently, atmospheric pressure in central part of a given Arctic sector drops.

  13. Egg cases of the graytail skate Bathyraja griseocauda and the cuphead skate Bathyraja scaphiops from the south-west Atlantic Ocean.

    Science.gov (United States)

    Mabragaña, E; Vazquez, D M; Gabbanelli, V; Sabadin, D; Barbini, S A; Lucifora, L O

    2017-09-01

    Egg cases of Bathyraja griseocauda were larger (140-142 mm in length) than those of Bathyraja scaphiops (88-90 mm in length) and their surface was relatively smooth, without denticles, prickles or any ornamentation. Egg cases of B. scaphiops had a relative coarse surface, covered with prickles of similar size. An identification key for the all described egg cases from Bathyraja occurring in the south-west Atlantic Ocean is provided. © 2017 The Fisheries Society of the British Isles.

  14. Precambrian crustal evolution and Cretaceous–Palaeogene faulting in West Greenland: Evolution of Neoarchaean supracrustal belts at the northern margin of the North Atlantic Craton, West Greenland

    Directory of Open Access Journals (Sweden)

    Stensgaard, Bo Møller

    2006-12-01

    Full Text Available The Archaean North Atlantic Craton of West Greenland collided at c. 1.9 Ga with a lesser-known Archaean craton to the north, to form the Nagssugtoqidian orogen. The Palaeoproterozoic metamorphic grade and strain intensity decrease northward through the orogen, allowing investigation of the reworked Archaean components in its northern part. Two Archaean supracrustal belts in this region – the Ikamiut and Kangilinaaq belts – are investigated here using field mapping, aeromagnetic data, zircon geochronology, and geochemistry. Both belts comprise quartzo-feldspathic and pelitic metasedimentary rocks, amphibolite, and minor calc-silicate rocks, anorthosite and ultramafic rocks. Pb-Pb and U-Pb dating of detrital zircons and host orthogneisses suggest deposition at c. 2800 Ma (Kangilinaaq belt and after 2740 Ma (Ikamiut belt; both belts have zircons with Neoarchaean metamorphic rims. Metasedimentary rocks and orthogneisses at Ikamiut share similar steep REE signatures with strong LREE enrichment, consistent with local derivation of the sediment and deposition directly onto or proximal to the regional orthogneiss precursors. Zircon age data from Kangilinaaq indicate both local and distal sources for the sediment there. Geochemical data for Kangilinaaq amphibolites indicate bimodal, mixed felsic–mafic source rocks with island-arc basaltic affinities, consistent with a shelf or arc setting. Both belts experienced a similar tectono-metamorphic history involving Neoarchaean amphibolite facies peak metamorphism at c. 2740–2700 Ma, possibly due to continued emplacement of tonalitic and granodioritic magmas. Nagssugtoqidian lower amphibolite facies metamorphism at c. 1850 Ma was associated with development of the large-scale F2 folds and shear zones that control the present outcrop pattern. The observed differences in the sources of the Kangilinaaq and Ikamiut belts and their shared post-Archaean history suggest they were formed in different

  15. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer and other instruments from Atlantic Companion in the Inner Sea - West Coast Scotland, Irish Sea and St. George's Channel and North Atlantic Ocean from 2011-05-29 to 2011-12-13 (NCEI Accession 0115715)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0115715 includes Surface underway, chemical, meteorological and physical data collected from Atlantic Companion in the Inner Sea - West Coast...

  16. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from surface underway observations using Carbon dioxide (CO2) gas analyzer and other instruments from Atlantic Companion in the Inner Sea - West Coast Scotland, Irish Sea and St. George's Channel and North Atlantic Ocean from 2013-02-11 to 2013-11-24 (NCEI Accession 0164749)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164749 includes chemical, meteorological, physical and surface underway data collected from Atlantic Companion in the Inner Sea - West Coast...

  17. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer and other instruments from Atlantic Companion in the Inner Sea - West Coast Scotland, Irish Sea and St. George's Channel and North Atlantic Ocean from 2014-02-22 to 2014-12-30 (NCEI Accession 0157359)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157359 includes Surface underway, chemical, meteorological and physical data collected from Atlantic Companion in the Inner Sea - West Coast...

  18. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from underway - surface observations using Barometric pressure sensor, Carbon dioxide (CO2) gas analyzer and other instruments from the Atlantic Companion in the Inner Sea - West Coast Scotland, Irish Sea and St. George's Channel and North Atlantic Ocean from 2006-06-11 to 2007-11-05 (NODC Accession 0115226)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115226 includes chemical, meteorological, physical and underway - surface data collected from Atlantic Companion in the Inner Sea - West Coast...

  19. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer and other instruments from Atlantic Cartier in the Inner Sea - West Coast Scotland, Irish Sea and St. George's Channel and North Atlantic Ocean from 2015-09-12 to 2015-12-22 (NCEI Accession 0157236)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157236 includes Surface underway, chemical, meteorological and physical data collected from Atlantic Cartier in the Inner Sea - West Coast Scotland,...

  20. Regional climatic and North Atlantic Oscillation signatures in West Virginia red cedar over the past millennium

    Science.gov (United States)

    D'Arrigo, Rosanne; Anchukaitis, Kevin J.; Buckley, Brendan; Cook, Ed; Wilson, Rob

    2012-03-01

    We describe a millennial length (~ 1500-yr) tree-ring chronology developed from West Virginia (WVA), USA red cedar (Juniperus virginiana) ring widths that is significantly correlated with local to regional temperature and precipitation for the region. Using ensemble methods of tree-ring standardization, above average ring widths are indicated for the period between ~ 1000 and 1300 CE, the approximate time of the Medieval Climate Anomaly (MCA), the most recent major warm episode prior to the modern era. The chronology then transitions to more negative overall growth persisting through much of the subsequent period known as the Little Ice Age (LIA). While WVA cedar growth levels during the MCA are broadly similar to the 20th century mean, the most positive values during the MCA are associated with RCS-standardized chronologies, which pseudoproxy tests reveal are likely biased artificially positive, warranting further investigation. This cedar record is significantly correlated with the NAO, due to the tendency for warmer, wetter conditions to occur in the eastern-central USA during the NAO's positive phase. These types of conditions are inferred for this cedar chronology during the MCA period, during which NAO reconstructions suggest a persistently-positive NAO state.

  1. Harmattan, Saharan heat low, and West African monsoon circulation: modulations on the Saharan dust outflow towards the North Atlantic

    Directory of Open Access Journals (Sweden)

    K. Schepanski

    2017-09-01

    Full Text Available The outflow of dust from the northern African continent towards the North Atlantic is stimulated by the atmospheric circulation over North Africa, which modulates the spatio-temporal distribution of dust source activation and consequently the entrainment of mineral dust into the boundary layer, as well as the transport of dust out of the source regions. The atmospheric circulation over the North African dust source regions, predominantly the Sahara and the Sahel, is characterized by three major circulation regimes: (1 the harmattan (trade winds, (2 the Saharan heat low (SHL, and (3 the West African monsoon circulation. The strength of the individual regimes controls the Saharan dust outflow by affecting the spatio-temporal distribution of dust emission, transport pathways, and deposition fluxes.This study aims at investigating the atmospheric circulation pattern over North Africa with regard to its role favouring dust emission and dust export towards the tropical North Atlantic. The focus of the study is on summer 2013 (June to August, during which the SALTRACE (Saharan Aerosol Long-range TRansport and Aerosol-Cloud interaction Experiment field campaign also took place. It involves satellite observations by the Spinning Enhanced Visible and InfraRed Imager (SEVIRI flying on board the geostationary Meteosat Second Generation (MSG satellite, which are analysed and used to infer a data set of active dust sources. The spatio-temporal distribution of dust source activation frequencies (DSAFs allows for linking the diurnal cycle of dust source activations to dominant meteorological controls on dust emission. In summer, Saharan dust source activations clearly differ from dust source activations over the Sahel regarding the time of day when dust emission begins. The Sahara is dominated by morning dust source activations predominantly driven by the breakdown of the nocturnal low-level jet. In contrast, dust source activations in the Sahel are

  2. Harmattan, Saharan heat low, and West African monsoon circulation: modulations on the Saharan dust outflow towards the North Atlantic

    Science.gov (United States)

    Schepanski, Kerstin; Heinold, Bernd; Tegen, Ina

    2017-09-01

    The outflow of dust from the northern African continent towards the North Atlantic is stimulated by the atmospheric circulation over North Africa, which modulates the spatio-temporal distribution of dust source activation and consequently the entrainment of mineral dust into the boundary layer, as well as the transport of dust out of the source regions. The atmospheric circulation over the North African dust source regions, predominantly the Sahara and the Sahel, is characterized by three major circulation regimes: (1) the harmattan (trade winds), (2) the Saharan heat low (SHL), and (3) the West African monsoon circulation. The strength of the individual regimes controls the Saharan dust outflow by affecting the spatio-temporal distribution of dust emission, transport pathways, and deposition fluxes.This study aims at investigating the atmospheric circulation pattern over North Africa with regard to its role favouring dust emission and dust export towards the tropical North Atlantic. The focus of the study is on summer 2013 (June to August), during which the SALTRACE (Saharan Aerosol Long-range TRansport and Aerosol-Cloud interaction Experiment) field campaign also took place. It involves satellite observations by the Spinning Enhanced Visible and InfraRed Imager (SEVIRI) flying on board the geostationary Meteosat Second Generation (MSG) satellite, which are analysed and used to infer a data set of active dust sources. The spatio-temporal distribution of dust source activation frequencies (DSAFs) allows for linking the diurnal cycle of dust source activations to dominant meteorological controls on dust emission. In summer, Saharan dust source activations clearly differ from dust source activations over the Sahel regarding the time of day when dust emission begins. The Sahara is dominated by morning dust source activations predominantly driven by the breakdown of the nocturnal low-level jet. In contrast, dust source activations in the Sahel are predominantly

  3. Regional variation of caesium-137 in minke whales ¤Balaenoptera acutorostrata¤ from West Greenland, the Northeast Atlantic and the North Sea

    DEFF Research Database (Denmark)

    Born, E.W.; Dahlgaard, H.; Riget, F.F.

    2002-01-01

    Levels of radioactive caesium (Cs-137) were determined in minke whales (Balaenoptera acutorostrata) from West Greenland, the Northeast Atlantic region and the North Sea. The sample consisted of muscle tissue from 135 minke whales caught in 1998 in 7 different areas: West Greenland, n = 44; East...... Greenland, n = 4; Jan Mayen, n = 22; Svalbard, n = 14; Barents Sea, n=20; Vestfjorden/Lofoten, n=14; the North Sea, n = 17. Mean Cs-137 levels in whales ranged from 0.298 (SD=0.083) Bq kg(-1) wet weight around Svalbard to 1.319 (SD=0.587) Bq kg(-1) wet weight in the North Sea. The finding of the highest...... caesium concentration in minke whales from the North Sea is in accordance with previous findings that Cs-137 levels in the marine environment of the North Atlantic region decrease with increasing distance from major point sources (i.e. nuclear-fuel reprocessing plants in the UK and France, and outflow...

  4. Tropospheric profiles of nitrogen oxides, ozone, and other related trace species measured over the Atlantic near the west coast of Europe

    Energy Technology Data Exchange (ETDEWEB)

    Rohrer, F.; Bruening, D.; Grobler, E.S.; Koppmann, R.; Kraus, A.B.; Schrimpf, W.; Weber, M.; Ehhalt, D.H. [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Atmosphaerische Chemie

    1997-12-31

    In June and December 1994, the concentrations of the nitrogen oxides NO, NO{sub 2} and NO{sub y} were measured together with ozone, photolysis frequency of NO{sub 2}, methane, CO, CO{sub 2}, PAN, and light hydrocarbons near the west coast of Europe above the Atlantic Ocean. Two vertical profiles for each season were obtained in the altitude range 1.5 to 12 km at four locations: near Prestwick (56 deg N, 9 deg W), Brest (49 deg N, 6 deg W), Faro (37 deg N, 12 deg W) and Tenerife (30 deg N, 18 deg W). The measured vertical profiles of NO are compared to the results of a low resolution 3-D chemical tracer model. (author)

  5. From “Balkanization” toward “West-Balkanization”: The Republic of Macedonia’s Euro- Atlantic prospects

    OpenAIRE

    Stojanovski, Strasko

    2013-01-01

    This paper follows the conceptual definitions offered in Eduard Said’s “Orientalization” and Maria Todorova’s “Balkanization” toward newly coined term of “West-Balkanization”, all as essential features of constructing the Otheness. In this sense, the identities generated by colective definition by the Other (The West), are seen in the abstract symbolic values of the region, which can be traced in real social and political events. Yet, in the modern age the only political perspective for the B...

  6. Organochlorine pesticides and polychlorinated biphenyls along an east-to-west gradient in subtropical North Atlantic surface water.

    Science.gov (United States)

    Lammel, Gerhard; Spitzy, Alejandro; Audy, Ondřej; Beckmann, Sabine; Codling, Garry P; Kretzschmann, Lisett; Kukučka, Petr; Stemmler, Irene

    2017-04-01

    Despite the fact that most persistent toxic substances have hardly been primarily emitted for several decades, their concentrations are only slowly decreasing in the global oceans. Surface seawater samples were collected along a 38°-24° N/28°-67° W transect in the subtropical North Atlantic Ocean. While the concentration levels of hexachlorobenzene (2.1-6.1 pg L -1 ), dichlorodiphenyltrichloroethane (DDT, up to 2.1 pg L -1 ) and polychlorinated biphenyls (PCB, 10.8-24.9 pg L -1 ) were in the same range as observed earlier in the North Atlantic, hexachlorocyclohexane (HCH, 90-627 pg L -1 ) was found elevated, partly also relative to previous measurements in the same sea region. Hereby, the ratio α-HCH/γ-HCH was very low, 0.09-0.13. Chlordane and endosulfan were found in the range pollution patterns in surface seawaters seem to be determined by atmospheric and oceanic transport patterns, rather than by mixing and air-sea equilibrium. The comparison with global multicompartment chemistry-transport model predictions of surface seawater levels indicate underestimated degradation of PCBs and overestimated emissions of endosulfan.

  7. Early life of key fish species, capelin Mallotus villosus and Atlantic cod Gadus morhua, in West Greenland

    DEFF Research Database (Denmark)

    Malanski, Evandro

    preferred prey size showed a slower increase during growth of the capelin larvae. Cyclopoid copepodites are food source for both capelin and cod, and there might be some competition for this item, however this plankton group is very abundant in the west coast of Greenland. However, the competition for food......Research involving the processes governing early life of fishes is important for understanding recruitment to the adult population. The forcing factors, like oceanographic processes and the associated plankton communities, impact the distribution and transport of fish larvae and determine...... knowledge on the role in the food web. The changes in environmental factors between subarctic and Arctic areas along the west coast of Greenland provide a unique study frame. Here, the period of high primary productivity is short and limited by seasonal changes in light, consequently prey availability...

  8. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Barometric pressure sensor, Carbon dioxide (CO2) gas analyzer and other instruments from Atlantic Companion in the Inner Sea - West Coast Scotland, Irish Sea and St. George's Channel and others from 2012-03-17 to 2012-12-06 (NCEI Accession 0157280)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157280 includes Surface underway, chemical, meteorological and physical data collected from Atlantic Companion in the Inner Sea - West Coast...

  9. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the DARVIN in the Inner Sea - West Coast Scotland and North Atlantic Ocean from 1991-06-14 to 1991-07-02 (NODC Accession 0113525)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0113525 includes chemical, discrete sample, physical and profile data collected from DARVIN in the Inner Sea - West Coast Scotland and North Atlantic...

  10. The impact of environmental variability on Atlantic mackerel Scomber scombrus larval abundance to the west of the British Isles

    DEFF Research Database (Denmark)

    Pitois, Sophie G.; Jansen, Teunis; Pinnegar, John

    2015-01-01

    The value of the Continuous Plankton Recorder (CPR) fish larvae dataset, with its extensive spatiotemporal coverage, has been recently demonstrated with studies on long-term changes over decadal scales in the abundance and distribution of fish larvae in relation to physical and biological factors...... abundances of zooplankton and the larger phytoplankton groups, to a system characterized by higher temperature, lower salinities, lower abundances of zooplankton and larger phytoplankton and higher abundances of the small phytoplankton species. Analysis revealed a very weak positive correlation between...... the Second principal component and mackerel larvae yearly abundance, attributed to the North Atlantic Oscillation (NAO). The results presented here are in broad accord with recent investigations that link climatic variability and dynamics of mackerel reproduction. However, the growing body of literature...

  11. Rhodolith beds are major CaCO3 bio-factories in the tropical South West Atlantic.

    Directory of Open Access Journals (Sweden)

    Gilberto M Amado-Filho

    Full Text Available Rhodoliths are nodules of non-geniculate coralline algae that occur in shallow waters (<150 m depth subjected to episodic disturbance. Rhodolith beds stand with kelp beds, seagrass meadows, and coralline algal reefs as one of the world's four largest macrophyte-dominated benthic communities. Geographic distribution of rhodolith beds is discontinuous, with large concentrations off Japan, Australia and the Gulf of California, as well as in the Mediterranean, North Atlantic, eastern Caribbean and Brazil. Although there are major gaps in terms of seabed habitat mapping, the largest rhodolith beds are purported to occur off Brazil, where these communities are recorded across a wide latitudinal range (2°N-27°S. To quantify their extent, we carried out an inter-reefal seabed habitat survey on the Abrolhos Shelf (16°50'-19°45'S off eastern Brazil, and confirmed the most expansive and contiguous rhodolith bed in the world, covering about 20,900 km(2. Distribution, extent, composition and structure of this bed were assessed with side scan sonar, remotely operated vehicles, and SCUBA. The mean rate of CaCO(3 production was estimated from in situ growth assays at 1.07 kg m(-2 yr(-1, with a total production rate of 0.025 Gt yr(-1, comparable to those of the world's largest biogenic CaCO(3 deposits. These gigantic rhodolith beds, of areal extent equivalent to the Great Barrier Reef, Australia, are a critical, yet poorly understood component of the tropical South Atlantic Ocean. Based on the relatively high vulnerability of coralline algae to ocean acidification, these beds are likely to experience a profound restructuring in the coming decades.

  12. Evidences of intraplate deformation in the West Madeira Abyssal Plain (eastern North Atlantic) from seismic reflection and multibeam swath bathymetry data

    Science.gov (United States)

    Roque, C.; Simões, M.; Lourenço, N.; Pinto de Abreu, M.

    2009-04-01

    The West Madeira Abyssal Plain is located in the eastern North Atlantic off Madeira Islands, forming part of the Canary Basin and reaching a mean water depth of 5300 m. This region is also located within Africa plate at about 500 km southwards from the Açores-Gibraltar plate boundary, and for that reason lacks seismic activity. Although this region being located in an intraplate setting, the presence of faulted sediments was reported in several works published during the eighties of last century following a study conducted in late 1970s to evaluate the feasibility of disposal of high-level radioactive wastes in the ocean. According these works, the Madeira Abyssal Plain sediments are cut by many normal growth faults and this deformation is a result of compaction and dewatering of the sediments. Evidences of tectonic deformation of oceanic sediments in intraplate settings are uncommon, but folded sediments and reverse faults extending into the basement, were recognized in the equatorial Indian Ocean and in the West African continental margin. Recently, during 2006 multi-channel seismic reflection and multibeam swath bathymetry surveys were carried out in the West Madeira Abyssal Plain by EMEPC in order to prepare the Portuguese proposal for the extension of the continental shelf. The seismic lines were acquired onboard R/V Akademik Shatskiy using a source of 5720 cu in bolt gun array, cable length of 7950 m and shot interval of 50.00 m. The multibeam swath bathymetry was acquired onboard NRP Gago Coutinho, and allowed a high resolution mapping of the main geomorphological features. The multichannel seismic lines, oriented WNW-ESE, image the Madeira island lower slope located at about 4000 m water depth and the almost flat abyssal plain at about 5300 m water depth. These seismic lines show a thick sedimentary succession that reaches a maximum thickness of about 1.5 sec twt in the deepest parts of the West Madeira Abyssal Plain, overlying an irregular diffractive

  13. Comparison of the Impact of the Arctic Oscillation and East Atlantic - West Russia Teleconnection on Interannual Variation in East Asian Winter Temperatures and Monsoon

    Science.gov (United States)

    Lim, Young-Kwon; Kim, Hae-Dong

    2014-01-01

    The large-scale impacts of the Arctic Oscillation (AO) and the East Atlantic/West Russia (EA/WR) teleconnection on the East Asian winter climate anomalies are compared for the past 34 winters focusing on 1) interannual monthly to seasonal temperature variability, 2) East Asian winter monsoon (EAWM), and 3) the Siberian high (SH) and cold surge. Regression analysis reveals warming by AO and EA/WR over mid-latitude East Asia during their positive phase and vice versa. The EA/WR impact is found to be comparable to the AO impact in affecting the East Asian temperature and monsoon. For example, warm (cold) months over mid-latitude East Asia during the positive (negative) AO are clearly seen when the AO and EA/WR are in the same phase. Near zero correlation is found between temperature and the AO phase when both teleconnections are in an opposite phase. The well-known negative relationship between SH and the AO phase is observed significantly more often when the AO is in the same phase with the EA/WR. Also, the indices of EAWM, cold surge, and SH are found to be more highly negative-correlated with the EA/WR rather than with the AO. The advective temperature change and associated circulation demonstrate that the anomalous large-scale field including the SH over the mid-latitude Asian inland is better represented by the EA/WR, influencing the East Asian winter climates. These results suggest that the impact of EA/WR should be considered more important than previously thought for a better understanding of East Asian winter temperature and monsoon variability.

  14. Influence of aerosol-radiative forcings on the diurnal and seasonal cycles of rainfall over West Africa and Eastern Atlantic Ocean using GCM simulations

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyu-Myong [University of Maryland Baltimore County, Baltimore, MD (United States); Lau, William K.M.; Sud, Yogesh C. [Laboratory for Atmospheres, NASA/GSFC, Greenbelt, MD (United States); Walker, Gregory K. [SAIC/General Sciences Operation, Beltsville, MD (United States)

    2010-07-15

    Effects of aerosol radiative forcing on the diurnal and seasonal cycles of precipitation over West Africa and eastern Atlantic Ocean are investigated for the boreal summer season: June-July-August. An eight year (2000-2007) average of GCM simulated rainfall data is compared with the corresponding TRMM rainfall data. The comparison shows that the amplitude of the diurnal cycles of rainfall over land and ocean are reasonably well simulated. Over land, the phase of the simulated diurnal cycle of precipitation peaks several hours earlier than that of the TRMM data. Corresponding differences over the ocean(s) are relatively smaller. Some of the key features of the aerosol induced model simulated field anomalies are: (a) aerosol direct radiative forcing which increases the atmospheric stability and reduces the daytime moist convection and convective precipitation; (b) the aerosol induced changes in the diurnal cycle of precipitation are out of phase with those of the TRMM data over land, but are in-phase over the ocean; (c) aerosols reduce the amplitude of the diurnal cycle of precipitation over land and enhance it over ocean. However, the phase of the diurnal cycle is not affected much by the aerosol radiative forcing both over land and ocean. During the boreal summer, aerosol radiative forcing and induced circulation and precipitation cool the Sahel and the southern part of Sahara desert more than the adjacent areas to the north and south, thereby shifting the peak meridional temperature gradient northward. Consequently, an anomalous easterly jet is found north of its climatological location. This anomalous jet is associated with increased cyclonic circulation to the south of its axis, resulting in an anomalous monsoon rain belt in the Sahel. (orig.)

  15. Atlantic Region

    NARCIS (Netherlands)

    Elands, B.H.M.; Bell, S.; Blok, J.

    2010-01-01

    Chapter 2 explores recreation and tourism practices in forest areas in the Atlantic region, which refers to the geographical area close to the North Sea and the Atlantic Ocean. The Atlantic countries described in this section are Belgium (Flanders and Wallonia), Denmark, Iceland, Ireland, the

  16. First record of Lagocephalus laevigatus (Tetraodontiformes, Tetraodontidae) from Galician waters (north-west Spain), a northernmost occurrence in the north-east Atlantic Ocean.

    Science.gov (United States)

    Bañón, R; Santás, V

    2011-05-01

    The first record of the smooth puffer Lagocephalus laevigatus from Galician waters (north-west Spain) is reported. Three possible mechanisms of introduction of the specimen are considered: natural displacement, the aquarist trade and transport in ballast water. © 2011 The Authors. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles.

  17. Distribution patterns of Chilean shallow-water sea anemones (Cnidaria: Anthozoa: Actiniaria, Corallimorpharia; with a discussion of the taxonomic and zoogeographic relationships between the actinofauna of the South East Pacific, the South West Atlantic and the Antarctic

    Directory of Open Access Journals (Sweden)

    Verena Häussermann

    2005-12-01

    Full Text Available The first complete zoogeographical analysis of Chilean shallow water sea anemones (Actiniaria and Corallimorpharia and their taxonomic relations with neighbouring faunas is provided, based on extensive recent sampling in combination with a literature review. Between 1994 and 2004, we collected more than 1000 specimens of 32 distinct species of Actiniaria and Corallimorpharia at more than 100 sites along the Chilean coast between Arica (18°30’S; 70°19’W and the Straits of Magellan (53°36’S 70°56’W. Sampling was done in the intertidal during low tides and in the subtidal by means of SCUBA diving down to depths of 40 m. The northern part of the Chilean fjord region showed the highest number of species (23. Our results contradict an abrupt general change in the marine faunal composition at 42°S, instead showing the continuation of species of the exposed coast and the joining of fjord species due to the availability of additional habitats in the richly structured fjord region south of 42°S, and also to eurybathy. The southern distribution limits of the species we found in northern and central Chile show only one significant concentration around the Peninsula Taitao (approx. 48°S. This either indicates a zoogeographic barrier for shallow water species at the Peninsula Taitao, or is a sampling artifact caused by poor data from the region between the Peninsula Taitao and the Straits of Magellan. According to the literature, 18 of the 63 described Chilean sea anemones (Pacific Ocean can also be found in Argentina (Atlantic Ocean and 13 in the Antarctic. However, many records and statuses of the common species of the South East Pacific and the South West Atlantic/Antarctic are uncertain or doubtful and need revision or confirmation.

  18. Archaeological Remains Accounting for the Presence and Exploitation of the North Atlantic Right Whale Eubalaena glacialis on the Portuguese Coast (Peniche, West Iberia), 16th to 17th Century

    Science.gov (United States)

    Teixeira, António; Venâncio, Rui; Brito, Cristina

    2014-01-01

    The former occurrence of the North Atlantic right whale Eubalaena glacialis on the Portuguese coast may be inferred from the historical range of that species in Europe and in NW Africa. It is generally accepted that it was the main prey of coastal whaling in the Middle Ages and in the pre-modern period, but this assumption still needs firming up based on biological and archaeological evidence. We describe the skeletal remains of right whales excavated at Peniche in 2001–2002, in association with archaeological artefacts. The whale bones were covered by sandy sediments on the old seashore and they have been tentatively dated around the 16th to 17th centuries. This study contributes material evidence to the former occurrence of E. glacialis in Portugal (West Iberia). Some whale bones show unequivocal man-made scars. These are associated to wounds from instruments with a sharp-cutting blade. This evidence for past human interaction may suggest that whaling for that species was active at Peniche around the early 17th century. PMID:24505251

  19. Archaeological remains accounting for the presence and exploitation of the North Atlantic right whale Eubalaena glacialis on the Portuguese Coast (Peniche, West Iberia, 16th to 17th Century.

    Directory of Open Access Journals (Sweden)

    António Teixeira

    Full Text Available The former occurrence of the North Atlantic right whale Eubalaena glacialis on the Portuguese coast may be inferred from the historical range of that species in Europe and in NW Africa. It is generally accepted that it was the main prey of coastal whaling in the Middle Ages and in the pre-modern period, but this assumption still needs firming up based on biological and archaeological evidence. We describe the skeletal remains of right whales excavated at Peniche in 2001-2002, in association with archaeological artefacts. The whale bones were covered by sandy sediments on the old seashore and they have been tentatively dated around the 16th to 17th centuries. This study contributes material evidence to the former occurrence of E. glacialis in Portugal (West Iberia. Some whale bones show unequivocal man-made scars. These are associated to wounds from instruments with a sharp-cutting blade. This evidence for past human interaction may suggest that whaling for that species was active at Peniche around the early 17th century.

  20. Monsoon rains over West Africa

    OpenAIRE

    Schupelius, Gert-Dietrich

    2011-01-01

    Potential mechanisms producing high or low seasonal rainfall in tropical West Africa are investigated for the period 1963–74 using monthly data of precipitation, surface pressure in the South Atlantic and rawinsondes, mainly in Africa. Contrary to widespread opinion, the South Atlantic pressures yielded no correlation; the best connection was between rainfall and upper-level African observations.DOI: 10.1111/j.2153-3490.1976.tb00700.x

  1. Shape and Size Complexity of Deep Seafloor Mounds on the Canary Basin (West to Canary Islands, Eastern Atlantic: A DEM-Based Geomorphometric Analysis of Domes and Volcanoes

    Directory of Open Access Journals (Sweden)

    Olga Sánchez-Guillamón

    2018-01-01

    Full Text Available Derived digital elevation models (DEMs are high-resolution acoustic technology that has proven to be a crucial morphometric data source for research into submarine environments. We present a morphometric analysis of forty deep seafloor edifices located to the west of Canary Islands, using a 150 m resolution bathymetric DEM. These seafloor structures are characterized as hydrothermal domes and volcanic edifices, based on a previous study, and they are also morphostructurally categorized into five types of edifice following an earlier classification. Edifice outline contours were manually delineated and the morphometric variables quantifying slope, size and shape of the edifices were then calculated using ArcGIS Analyst tools. In addition, we performed a principal component analysis (PCA where ten morphometric variables explain 84% of the total variance in edifice morphology. Most variables show a large spread and some overlap, with clear separations between the types of mounds. Based on these analyses, a morphometric growth model is proposed for both the hydrothermal domes and volcanic edifices. The model takes into account both the size and shape complexity of these seafloor structures. Grow occurs via two distinct pathways: the volcanoes predominantly grow upwards, becoming large cones, while the domes preferentially increase in volume through enlargement of the basal area.

  2. Reefs of the Jurassic-Cretaceous west Atlantic margin : an overview of settings, types, facies trends, depositional styles and terminations (with reservoir implications)

    Energy Technology Data Exchange (ETDEWEB)

    Eliuk, L.S. [GeoTours Consulting Inc., Calgary, AB (Canada)

    2005-07-01

    In the past 40 years, approximately 20 exploratory wells have been drilled in the Jurassic-Cretaceous Abenaki Formation near-margin carbonate sequences off the Atlantic coast. These include the pioneer wells drilled in the 1970s offshore Nova Scotia, a mid-1980s group including 3 Baltimore Canyon wells in the United States, and those following EnCana's Deep Panuke 1998 gas discovery offshore Nova Scotia. A comparison of these wells has revealed 2 margin settings over deep basement highs versus prograded carbonates, 3 reef-reef mound/slope types, and an overall vertical facies trend that reveals an upward progression from microbial-rich slope beds to shallower forereef to reef and reef-flat beds initially rich in coralline sponges, followed by more microsolenid corals and bioeroded stormreworked coral-rich and oncolitic debris beds up to oolitic shoals. The top of carbonate bank sequences may be replaced gradually by shallow-water siliciclastics near deltaic depocentres or abruptly by deeper-water sponge-reef-derived beds. Smaller-scale similar flooding and shoaling patterns exist within this overall style that allow sequence or parasequence subdivision in Nova Scotia following an initial oolitic flooding event immediately above the Misaine shale. The association of deltas and reef termination suggests drowning by nutrient poisoning. The mid-Mesozoic biotas appear more robust by living in close proximity to siliciclastics. Being at the carbonate shelf margin and in a non-argillaceous shallow water reef-associated facies would appear to be necessary requirements for gas-bearing reservoir development in the Abenaki, but they are not sufficient. Originally porous oolitic grainstones are tight in areas where they are deeply buried in the Panuke area. Siliciclastic burial influenced the limestone cementation, resulting in potential stratigraphic trapping where offset by subsurface dolomitization and leaching fed by fractures or faults in coarser reef

  3. Isotopic evidence for dead fish maintenance of Florida red tides, with implications for coastal fisheries over both source regions of the West Florida shelf and within downstream waters of the South Atlantic Bight

    Science.gov (United States)

    Walsh, J. J.; Weisberg, R. H.; Lenes, J. M.; Chen, F. R.; Dieterle, D. A.; Zheng, L.; Carder, K. L.; Vargo, G. A.; Havens, J. A.; Peebles, E.; Hollander, D. J.; He, R.; Heil, C. A.; Mahmoudi, B.; Landsberg, J. H.

    2009-01-01

    Toxic Florida red tides of the dinoflagellate Kareniabrevis have downstream consequences of 500-1000 km spatial extent. Fish stocks, shellfish beds, and harmful algal blooms of similar species occupy the same continental shelf waters of the southeastern United States, amounting to economic losses of more than 25 million dollars in some years. Under the aegis of the Center for Prediction of Red tides, we are now developing coupled biophysical models of the conditions that lead to red tides and impacted coastal fisheries, from the Florida Panhandle to Cape Hatteras. Here, a nitrogen isotope budget of the coastal food web of the West Florida shelf (WFS) and the downstream South Atlantic Bight (SAB) reaffirms that diazotrophs are the initial nutrient source for onset of red tides and now identifies clupeid fish as the major recycled nutrient source for their maintenance. The recent isotope budget of WFS and SAB coastal waters during 1998-2001 indicates that since prehistoric times of Timacua Indian settlements along the Georgia coast during 1075, ∼50% of the nutrients required for large red tides of >1 μg chl l -1 of K.brevis have been derived from nitrogen-fixers, with the other half from decomposing dead sardines and herrings. During 2001, >90% of the harvest of WFS clupeids was by large ichthyotoxic red tides of >10 μg chl l -1 of K.brevis, rather than by fishermen. After onset of the usual red tides in summer of 2006 and 2007, the simulated subsequent fall exports of Florida red tides in September 2007 to North Carolina shelf waters replicate observations of just ∼1 μg chl l -1 on the WFS that year. In contrast, the earlier red tides of >10 μg chl l -1 left behind off West Florida during 2006, with less physical export, are instead 10-fold larger than those of 2007. Earlier, 55 fish kills were associated with these coastal red tides during September 2006, between Tampa and Naples. Yet, only six fish kills were reported there in September 2007. With little

  4. An Atlantic influence on Amazon rainfall

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Jin-Ho [University of Maryland, Department of Atmospheric and Oceanic Science, College Park, MD (United States); Zeng, Ning [University of Maryland, Earth System Science Interdisciplinary Center, College Park, MD (United States); University of Maryland, Department of Atmospheric and Oceanic Science, College Park, MD (United States)

    2010-02-15

    Rainfall variability over the Amazon basin has often been linked to variations in Pacific sea surface temperature (SST), and in particular, to the El Nino/Southern Oscillation (ENSO). However, only a fraction of Amazon rainfall variability can be explained by ENSO. Building upon the recent work of Zeng (Environ Res Lett 3:014002, 2008), here we provide further evidence for an influence on Amazon rainfall from the tropical Atlantic Ocean. The strength of the North Atlantic influence is found to be comparable to the better-known Pacific ENSO connection. The tropical South Atlantic Ocean also shows some influence during the wet-to-dry season transition period. The Atlantic influence is through changes in the north-south divergent circulation and the movement of the ITCZ following warm SST. Therefore, it is strongest in the southern part of the Amazon basin during the Amazon's dry season (July-October). In contrast, the ENSO related teleconnection is through anomalous east-west Walker circulation with largely concentrated in the eastern (lower) Amazon. This ENSO connection is seasonally locked to boreal winter. A complication due to the influence of ENSO on Atlantic SST causes an apparent North Atlantic SST lag of Amazon rainfall. Removing ENSO from North Atlantic SST via linear regression resolves this causality problem in that the residual Atlantic variability correlates well and is in phase with the Amazon rainfall. A strong Atlantic influence during boreal summer and autumn is particularly significant in terms of the impact on the hydro-ecosystem which is most vulnerable during the dry season, as highlighted by the severe 2005 Amazon drought. Such findings have implications for both seasonal-interannual climate prediction and understanding the longer-term changes of the Amazon rainforest. (orig.)

  5. future changes in seasonal-mean precipitation over west africa ...

    African Journals Online (AJOL)

    HOD

    Atlantic Ocean Dipole on West African Summer. Precipitation. Journal of Climate, 24: 1184-1197. 2011. [5] Rodrigues, L. R. L., García-Serrano, J. and Doblas-. Reyes, F. Seasonal prediction of the intraseasonal variability of the West African monsoon precipitation. Física de la Tierra. 25: 83-97. 2013. [6] Mahmood, R.; Pielke, ...

  6. 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.

  7. 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,...

  8. 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 Caribbean...

  9. Collision physics going west

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    The centroid of proton-antiproton physics is moving west across the Atlantic concluded Luigi Di Leila of CERN in his summary talk at the Topical Workshop on Proton-Antiproton Collider Physics, held at Fermilab in June. Previous meetings in this series had been dominated by results from CERN's big proton-antiproton collider, dating back to 1981. However last year saw the first physics run at Fermilab's collider, and although the number of collisions in the big CDF detector was only about one thirtieth of the score so far at CERN, the increased collision energy at Fermilab of 1.8 TeV (1800 GeV, compared to the routine 630 GeV at CERN) is already paying dividends

  10. Analyse sismo-stratigraphique du bassin d'Abda (Maroc occidental), exemple de structures inverses pendant le rifting atlantiqueSeismo-stratigraphic analysis of the Abda Basin (West Morocco): a case of reverse structures during the Atlantic rifting

    Science.gov (United States)

    Echarfaoui, Hassan; Hafid, Mohamed; Salem, Abdallah Aı̈t; Abderrahmane, Aı̈t Fora

    The review of the seismic reflection and well data from the coastal Abda Basin (western Morocco) shows that its Triassic and Jurassic sequences were deposited in a submeridean sag basin, whose eastern margin is characterised by progressive truncations and pinching out of these sequences against a prominent Palaeozoic high. The uplift of this latter is interpreted as a response to an Upper Triassic-Middle Jurassic local compressional event that controlled Triassic-Jurassic sedimentation within the Abda Basin. The present day 'West Meseta Flexure' is a surface expression of this uplift. To cite this article: H. Echarfaoui et al., C. R. Geoscience 334 (2002) 371-377.

  11. (Ceramiales, Rhodophyta) from the Canary Islands, eastern Atlantic

    African Journals Online (AJOL)

    The genus Osmundea is a strongly supported monophyletic group within the Laurencia complex and shows a disjunct distribution occurring in the North-East and South-West Pacific, the Indian and Atlantic oceans and the Mediterranean Sea. Its phenotypic plasticity on the Canary Islands may be the result of the high ...

  12. West Africa

    African Journals Online (AJOL)

    ing to the timing of a future adoption of a single currency by the West African states. In doing so, ... tures and almost all these countries depend on donor funds to finance their budgets, the risk that ... national currencies co-exist with a common currency, and a full monetary union where a common central bank exists to for-.

  13. A millennium of north-east Atlantic cod juvenile growth trajectories inferred from archaeological otoliths.

    Directory of Open Access Journals (Sweden)

    Guðbjörg Ásta Ólafsdóttir

    Full Text Available Archaeological excavations of historical fishing sites across the North Atlantic have recovered high quantities of Atlantic cod (Gadus morhua bones. In the current study we use Atlantic cod otoliths from archaeological excavations of a historical fishing sites in north-west Iceland, dated to AD 970 -AD 1910 to examine historical growth trajectories of cod. No large scale growth variations or shifts in growth patterns were observed in the current chronologies, supporting the stability of historical Atlantic cod growth trajectories. The most significant variation in growth patterns was consistent with those that have been observed in recent times, for example, reduced early juvenile growth during periods of colder ocean temperature. The current results represent a high resolution chronological record of north-east Atlantic cod growth, greatly increasing the prior temporal range of such data, thereby providing a valuable baseline for a broad range of studies on Atlantic cod growth.

  14. Kinematics of the South Atlantic rift

    Science.gov (United States)

    Heine, C.; Zoethout, J.; Müller, R. D.

    2013-08-01

    The South Atlantic rift basin evolved as a branch of a large Jurassic-Cretaceous intraplate rift zone between the African and South American plates during the final break-up of western Gondwana. While the relative motions between South America and Africa for post-break-up times are well resolved, many issues pertaining to the fit reconstruction and particularly the relation between kinematics and lithosphere dynamics during pre-break-up 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-break-up 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 Zones, we have been able to indirectly construct the kinematic history of the pre-break-up 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 from 140 Ma until late Hauterivian times (≈126 Ma) when rift activity along in the equatorial Atlantic domain started to increase significantly. During this initial ≈14 Myr-long stretching episode the pre-salt basin width on the conjugate Brazilian and west African margins is generated. An intermediate stage between ≈126 Ma and base Aptian is characterised by strain localisation, rapid lithospheric weakening in the

  15. GARP Atlantic Tropical Experiment

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The GARP Atlantic Tropical Experiment (GATE) was the first major international experiment of the Global Atmospheric Research Program (GARP). It was conducted over...

  16. Tsunami Forecasting in the Atlantic Basin

    Science.gov (United States)

    Knight, W. R.; Whitmore, P.; Sterling, K.; Hale, D. A.; Bahng, B.

    2012-12-01

    The mission of the West Coast and Alaska Tsunami Warning Center (WCATWC) is to provide advance tsunami warning and guidance to coastal communities within its Area-of-Responsibility (AOR). Predictive tsunami models, based on the shallow water wave equations, are an important part of the Center's guidance support. An Atlantic-based counterpart to the long-standing forecasting ability in the Pacific known as the Alaska Tsunami Forecast Model (ATFM) is now developed. The Atlantic forecasting method is based on ATFM version 2 which contains advanced capabilities over the original model; including better handling of the dynamic interactions between grids, inundation over dry land, new forecast model products, an optional non-hydrostatic approach, and the ability to pre-compute larger and more finely gridded regions using parallel computational techniques. The wide and nearly continuous Atlantic shelf region presents a challenge for forecast models. Our solution to this problem has been to develop a single unbroken high resolution sub-mesh (currently 30 arc-seconds), trimmed to the shelf break. This allows for edge wave propagation and for kilometer scale bathymetric feature resolution. Terminating the fine mesh at the 2000m isobath keeps the number of grid points manageable while allowing for a coarse (4 minute) mesh to adequately resolve deep water tsunami dynamics. Higher resolution sub-meshes are then included around coastal forecast points of interest. The WCATWC Atlantic AOR includes eastern U.S. and Canada, the U.S. Gulf of Mexico, Puerto Rico, and the Virgin Islands. Puerto Rico and the Virgin Islands are in very close proximity to well-known tsunami sources. Because travel times are under an hour and response must be immediate, our focus is on pre-computing many tsunami source "scenarios" and compiling those results into a database accessible and calibrated with observations during an event. Seismic source evaluation determines the order of model pre

  17. Nursery areas and recruitment variation of Northeast Atlantic mackerel (Scomber scombrus)

    DEFF Research Database (Denmark)

    Jansen, Teunis; Kristensen, Kasper; Van der Kooij, Jeroen

    2015-01-01

    There are currently no dedicated recruitment survey data available in support of the assessment of the abundance and distribution of Northeast Atlantic (NEA) mackerel (Scomber scombrus), one of the most widespread and commercially important fish stocks in the North Atlantic. This is despite the f......, showing that the most important nursery areas are around Ireland, north and west of Scotland, in the northern North Sea north of 598Nand, to some extent, also in the Bay of Biscay....

  18. Natal homing and connectivity in Atlantic bluefin tuna populations.

    Science.gov (United States)

    Rooker, Jay R; Secor, David H; De Metrio, Gregorio; Schloesser, Ryan; Block, Barbara A; Neilson, John D

    2008-10-31

    Atlantic bluefin tuna populations are in steep decline, and an improved understanding of connectivity between individuals from eastern (Mediterranean Sea) and western (Gulf of Mexico) spawning areas is needed to manage remaining fisheries. Chemical signatures in the otoliths of yearlings from regional nurseries were distinct and served as natural tags to assess natal homing and mixing. Adults showed high rates of natal homing to both eastern and western spawning areas. Trans-Atlantic movement (east to west) was significant and size-dependent, with individuals of Mediterranean origin mixing with the western population in the U.S. Atlantic. The largest (oldest) bluefin tuna collected near the northern extent of their range in North American waters were almost exclusively of western origin, indicating that this region represents critical habitat for the western population.

  19. Temperature, salinity, nutrient, and primary production collected by bottle and CTD in the North Atlantic Ocean from 8/25/1903 - 11/14/1997 (NODC Accession 0000101)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile, algal species, and other data were collected using water bottle or CTD casts in the North Atlantic Ocean from WEST-HINDER and other platforms....

  20. 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...

  1. The Distribution of Dissolved Iron in the West Atlantic Ocean

    NARCIS (Netherlands)

    Rijkenberg, Micha J. A.; Middag, Rob; Laan, Patrick; Gerringa, Loes J. A.; van Aken, Hendrik M.; Schoemann, Veronique; de Jong, Jeroen T.M.; Baar, de Hein J.W.

    2014-01-01

    Iron (Fe) is an essential trace element for marine life. Extremely low Fe concentrations limit primary production and nitrogen fixation in large parts of the oceans and consequently influence ocean ecosystem functioning. The importance of Fe for ocean ecosystems makes Fe one of the core chemical

  2. Atlantic Nessologies: Image, Territory, Value

    Directory of Open Access Journals (Sweden)

    Francisco-]. Hernández Adrián

    2006-01-01

    Full Text Available This essay addresses the emerging field of Atlantic Studies and questions the status of "the Atlantic" as an object of study. Rather than assuming a self-evident grid where Atlantic cultural phenomena oscillate between such poles as "centers and peripheries," or "the colonizer and the colonized," I consider a different formulation of the Atlantic. Taking as a starting point an analysis of a poem by Tomás Morales, a modernista poet from the Canary Islands, my essay outlines the notion of "Atlantic nessologies." Three parallel departures are offered from this analysis: image (or the realm of the imaginary; territory (or spatial and geopolitical inscriptions of the Atlantic in western space-time; and value (or those ethical and political dimensions that can be drawn from Atlantic specificities. Critical engagements with the Atlantic, my essay concludes, can be anchored in "nessological" readings in which neither local, singular perspectives contained in islands, nor wider, more panoramic views of the Atlantic, ought to escape critics. Instead, the work of engaging the Atlantic from multiple perspectives and locations should express itself as a field of critical/political strategies coordinated against perennial re-inscriptions of Eurocentric totality.

  3. Persistence of Allegheny woodrats Neotoma magister across the mid-Atlantic Appalachian Highlands landscape, USA

    Science.gov (United States)

    W. Mark Ford; Steven B. Castleberry; Michael T. Mengak; Jane L. Rodrigue; Daniel J. Feller; Kevin R. Russell

    2006-01-01

    We examined a suite of macro-habitat and landscape variables around active and inactive Allegheny woodrat Neotoma magister colony sites in the Appalachian Mountains of the mid-Atlantic Highlands of Maryland, Virginia, and West Virginia using an information-theoretic modeling approach. Logistic regression analyses suggested that Allegheny woodrat presence was related...

  4. Historical biogeography in tropical Atlantic populations of Cladophoropsis membranacea and related species

    NARCIS (Netherlands)

    Kooistra, Wiebe Hendrik Cornelis Frederik

    1993-01-01

    The Tethys was an equatorial sea that came into existence some 200 million years ago and closed about 12 million years ago thereby fragmenting the pan-tropical marine flora. The tropical provinces of the eastern Pacific, the lndo-West Pacific, the eastern Atlantic, and the Caribbean are today's

  5. Changes in Greenland’s peripheral glaciers linked to the North Atlantic Oscillation

    DEFF Research Database (Denmark)

    Bjørk, A. A.; Aagaard, S.; Lütt, A.

    2018-01-01

    associated with the North Atlantic Oscillation (NAO), with a distinct east–west asymmetry; positive phases of the NAO increase accumulation, and thereby glacier growth, in the eastern periphery, whereas opposite effects are observed in the western periphery. Thus, with projected trends towards positive NAO...

  6. 78 FR 59878 - Atlantic Highly Migratory Species; Commercial Atlantic Aggregated Large Coastal Shark (LCS...

    Science.gov (United States)

    2013-09-30

    ... 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: National... hammerhead sharks in the Atlantic region, and blacknose sharks and non-blacknose SCS in the Atlantic region...

  7. Stratified flows and internal waves in the Vema Fracture Zone of the Mid Atlantic Ridge

    Science.gov (United States)

    Makarenko, Nikolay; Morozov, Eugene; Tarakanov, Roman; Demidova, Tatiana; Frey, Dmitri; Grigorenko, Klim

    2017-04-01

    In this paper, we study stratified flows and internal waves in the Vema fracture zone of the Mid Atlantic Ridge. This fracture provides intense transportation of cold abyssal waters from the West Atlantic to the equatorial region of the East Atlantic [1]. The results of measurements [2,3] carried out in the cruises of RV Akademik Sergey Vavilov in 2014-2016 are presented. The structure of the near-bottom flow is studied experimentally on the basis of CTD- and LADCP profiling. Theoretical analysis involves mathematical formulation of stratified fluid flow which uses CTD-data obtained from field observation. Spectral properties and kinematic characteristics of internal waves are calculated and discussed. This work was supported by RFBR (grants No 15-01-03942, 16-35-50158). References [1] Morozov E., Demidov A., Tarakanov R. and Zenk W. Abyssal Channels in the Atlantic Ocean: Water Structure and Flows, Springer, Dordrecht, 2010. [2] Morozov E.G., Tarakanov R.Yu., and Makarenko N.I. Flows of Antarctic Bottom Water through fractures in the southern part of the North Mid Atlantic Ridge, Oceanology, 2015, 55, 796-800. [3] Grigorenko K.S., Makarenko N.I., Morozov E.G., Tarakanov R.Yu., and Frey D.I. Stratified flows and internal waves in the Central West Atlantic, J. Physics: Conf. Series, 2016, 722, 012011.

  8. Populations genetic analysis of nuclear and mitochondrial loci in skin biopsies collected from central and northeastern North Atlantic humpback whales (Megaptera novaeangliae) : Population identity and migratory destinations

    NARCIS (Netherlands)

    Larsen, AH; Sigurjonsson, J; Oien, N; Vikingsson, G; Palsboll, P

    1996-01-01

    It has been speculated that humpback whales, Megaptera novaeangliae, from the northeastern North Atlantic breed in tropical waters off the coast of West Africa and therefore that they represent a separate breeding population from that which winters in the West Indies. We determined the genotype at

  9. Atlantic Oceanographic and Meteorological Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Atlantic Oceanographic and Meteorological Laboratory conducts research to understand the physical, chemical, and biological characteristics and processes of the...

  10. 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.

  11. The establishment of Atlantic Water transport as a topographically trapped slope current off Scotland

    Directory of Open Access Journals (Sweden)

    Qin Zhou

    2013-05-01

    Full Text Available Atlantic Water, with its origin in the western Atlantic, enters the Nordic Seas partly as a barotropic current following the continental slope. This water mass is carried across the Atlantic by the baroclinic North Atlantic Current (NAC. When the NAC meets the continental slope at the east side of the Atlantic, some of the transport is converted to barotropic transport over the slope before continuing northward. Here, we show that this baroclinic to barotropic conversion is in agreement with geostrophic theory. Historical observations show that the transport of the slope current increases significantly from the Rockall Channel (RC to the Faroe–Shetland Channel (FSC. Geostrophy predicts that with a northward decreasing buoyancy, baroclinic currents from the west will be transferred into northward topographically steered barotropic flow. We use hydrographic data from two sections crossing the continental slope, one located in the RC and another in the FSC, to estimate baroclinic and barotropic transport changes over the slope, within the framework of geostrophic dynamics. Our results indicate that ~1 Sv of the cross-slope baroclinic flow is mainly converted to northward barotropic transport above the 200–500m isobaths, which is consistent with observed transport changes between the RC and the FSC. Similar processes are also likely to occur further south, along the eastern Atlantic margin. This shows that AW within the slope current in the FSC is derived from both the eastern and the western Atlantic, in agreement with earlier studies of AW inflow to the Nordic Seas.

  12. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from DISCOVERY in the Inner Sea - West Coast Scotland and North Atlantic Ocean from 2012-08-02 to 2012-08-15 (NCEI Accession 0157313)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157313 includes chemical, discrete sample, physical and profile data collected from DISCOVERY in the Inner Sea - West Coast Scotland and North...

  13. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from RRS JAMES COOK in the Inner Sea - West Coast Scotland and North Atlantic Ocean from 2013-05-10 to 2013-05-24 (NCEI Accession 0157282)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157282 includes chemical, discrete sample, optical, physical and profile data collected from RRS JAMES COOK in the Inner Sea - West Coast Scotland...

  14. 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.

  15. Cenozoic uplift and subsidence in the North Atlantic region

    DEFF Research Database (Denmark)

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

    2009-01-01

    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...... and the surrounding areas. (2) A regional increase in subsidence in the offshore marginal areas of Norway, the northern North Sea, the northern British Isles and west Greenland took place in the Eocene (ca 57-35 Ma). (3) The Oligocene and Miocene (35-5 Ma) were characterized by regional tectonic quiescence, with only...

  16. West and East

    Directory of Open Access Journals (Sweden)

    Alexander Rappaport

    2017-12-01

    Full Text Available The topic “West-East” has a clear cultural and historical meaning. Orthodox temples face East. The way from West to East and from East to West is tens of thousands of kilometers long and has a special meaning. It differs from the way from North to South: the horizontal axes connect regions, while the vertical axis (Earth-Sky connects the worlds. The expansion of Eurasian tribes occurred along the East-West axis – the world horizontal way. Today the cultural memory of people in the East and West finds itself in the theatre of new dramas of existence and new forces. With the advances in electronic technologies, the world movements seem to have sunk in the depth of the chthonian past to come up anew to the surface of fantastic speeds and momentary connections. A new type of planetary landscape-space relation appears, giving no place for West and East.

  17. A visual and acoustic survey for harbour porpoises off North-West ...

    African Journals Online (AJOL)

    The distribution of harbour porpoises Phocoena phocoena in southern Europe and along the Atlantic African coast is poorly understood, with tentative assessments suggesting a discrete West African population with a northern limit around the Straits of Gibraltar. This study describes visual and acoustic surveys for porpoises ...

  18. Manganiferous minerals of the epidote group from the Archaean basement of West Greenland

    DEFF Research Database (Denmark)

    Katerinopoulou, Anna; Balic Zunic, Tonci; Kolb, Jochen

    2014-01-01

    The chemical compositions and crystal structures of Mn3+-containing minerals from the epidote group in Greenland rocks are investigated and described in detail. They occur in hydrothermally altered Archaean mafic sequences within the gneissic complex of the North Atlantic craton of West Greenland...

  19. The effects of the spreading of the Central Atlantic during the Middle Jurassic on dinosaur faunas

    OpenAIRE

    Clark, N.D.L.

    2012-01-01

    The spreading of the Central Atlantic is a complex series of\\ud events that include a ridge jump to the east and a ridge jump to the west at c. 170Ma and c. 162Ma respectively. These jumps were influenced by plate interactions as Laurasia separated from Gondwana, although the second jump may have been influenced by spreading in the Gulf of Mexico, which occurred at about the same time. Dinosaur evolution and diversity were influenced by the spreading of the Central Atlantic that split Laurasi...

  20. Geological evolution and hydrocarbon potential of the Hatton Basin (UK sector), north-east Atlantic Ocean

    OpenAIRE

    McInroy, David; Hitchen, Ken

    2008-01-01

    The deep-water Hatton Basin (flanked by the Hatton and Rockall Highs) is located 600km west of Scotland (NE Atlantic Ocean) on the western margin of the Eurasian continental plate. Prior to Atlantic opening the area was adjacent to SE Greenland. The basin straddles the UK/Irish median line. Water depths increase southwards from 1000m to over 1300m. The basin has never been licensed for hydrocarbon exploration and is currently the subject of ownership negotiations related to the UN Conven...

  1. History and the West Indian nation

    Directory of Open Access Journals (Sweden)

    Frank Birbalsingh

    1998-07-01

    Full Text Available [First paragraph] The Art of Kamau Brathwaite. STEWART BROWN (ed.. Bridgend, Wales: Seren/Poetry Wales Press, 1995. 275 pp. (Cloth US$ 50.00, Paper US$ 22.95 Atlantic Passages: History, Community, and Language in the Fiction of Sam Selvon. MARK LOOKER. New York: Peter Lang, 1996. x + 243 pp. (Cloth n.p. Caliban's Curse: George Lamming and the Revisioning of History. SUPRIYA NAIR. Ann Arbor: University of Michigan Press, 1996. viii + 171 pp. (Cloth US$ 34.50 Phyllis Shand Allfrey: A Caribbean Life. LlZABETH PARAVISINI-GEBERT. New Brunswick NJ: Rutgers University Press, 1996. xii + 335 pp. (Cloth US$ 55.00, Paper US$ 18.95 Of the four books to be considered here, those on Brathwaite, Selvon, and Lamming fit snugly together into a natural category of literature that has to do with the emergence of a Creole or African-centered Caribbean culture, and related issues of race, color, class, history, and nationality. The fourth is a biography of Phyllis Shand Allfrey, a white West Indian, who is of an altogether different race, color, and class than from the other three. Yet the four books are linked together by nationality, for Allfrey and the others are all citizens of one region, the English-speaking West Indies, which, as the Federation of the West Indies between 1958 and 1962, formed a single nation.

  2. Metazoan parasite infection in the swordfish, Xiphias gladius, from the Mediterranean Sea and comparison with Atlantic populations: implications for its stock characterization

    Directory of Open Access Journals (Sweden)

    Mattiucci Simonetta

    2014-01-01

    Full Text Available Thirteen parasite taxa were identified in the Mediterranean swordfish by morphological and genetic/molecular methods. The comparison of the identified parasite taxa and parasitic infection values observed in the Mediterranean swordfish showed statistically significant differences with respect to those reported for its Atlantic populations. A stepwise Linear Discriminant Analysis of the individual fish examined showed a separation among three groups: one including fish from the Mediterranean Sea (CTS, STS, and IOS; one consisting of fish from the Central South (CS, Eastern Tropical (ET, and Equatorial (TEQ Atlantic; and a third comprising the fish sampled from the North-West Atlantic (NW; the CN Atlantic sample was more similar to the first group rather than to the other Atlantic ones. The nematodes Hysterothylacium petteri and Anisakis pegreffii were the species that contributed most to the characterization of the Mediterranean swordfish samples with respect to these Atlantic ones. Anisakis brevispiculata, A. physeteris, A. paggiae, Anisakis sp. 2, Hysterothylacium incurvum, Hepatoxylon trichiuri, Sphyriocephalus viridis, and their high infection levels were associated with the swordfish from the Central and the Southern Atlantic areas. Finally, H. corrugatum, A. simplex (s.s., Rhadinorhynchus pristis, and Bolbosoma vasculosum were related to the fish from the North-West (NW Atlantic area. These results indicate that some parasites, particularly Anisakis spp. larvae identified by genetic markers, could be used as “biological tags” and support the existence of a Mediterranean swordfish stock.

  3. Metazoan parasite infection in the swordfish, Xiphias gladius, from the Mediterranean Sea and comparison with Atlantic populations: implications for its stock characterization.

    Science.gov (United States)

    Mattiucci, Simonetta; Garcia, Alexandra; Cipriani, Paolo; Santos, Miguel Neves; Nascetti, Giuseppe; Cimmaruta, Roberta

    2014-01-01

    Thirteen parasite taxa were identified in the Mediterranean swordfish by morphological and genetic/molecular methods. The comparison of the identified parasite taxa and parasitic infection values observed in the Mediterranean swordfish showed statistically significant differences with respect to those reported for its Atlantic populations. A stepwise Linear Discriminant Analysis of the individual fish examined showed a separation among three groups: one including fish from the Mediterranean Sea (CTS, STS, and IOS); one consisting of fish from the Central South (CS), Eastern Tropical (ET), and Equatorial (TEQ) Atlantic; and a third comprising the fish sampled from the North-West Atlantic (NW); the CN Atlantic sample was more similar to the first group rather than to the other Atlantic ones. The nematodes Hysterothylacium petteri and Anisakis pegreffii were the species that contributed most to the characterization of the Mediterranean swordfish samples with respect to these Atlantic ones. Anisakis brevispiculata, A. physeteris, A. paggiae, Anisakis sp. 2, Hysterothylacium incurvum, Hepatoxylon trichiuri, Sphyriocephalus viridis, and their high infection levels were associated with the swordfish from the Central and the Southern Atlantic areas. Finally, H. corrugatum, A. simplex (s.s.), Rhadinorhynchus pristis, and Bolbosoma vasculosum were related to the fish from the North-West (NW) Atlantic area. These results indicate that some parasites, particularly Anisakis spp. larvae identified by genetic markers, could be used as "biological tags" and support the existence of a Mediterranean swordfish stock. © S. Mattiucci et al., published by EDP Sciences, 2014.

  4. Interdecadal variation of the West African summer monsoon during 1979-2010 and associated variability

    Energy Technology Data Exchange (ETDEWEB)

    Li, Huanlian [Chinese Academy of Sciences, Nansen-Zhu International Research Centre, Institute of Atmospheric Physics, Beijing (China); Graduate University of Chinese Academy of Sciences, Beijing (China); Chinese Academy of Sciences, Climate Change Research Center, Beijing (China); Wang, Huijun [Chinese Academy of Sciences, Nansen-Zhu International Research Centre, Institute of Atmospheric Physics, Beijing (China); Chinese Academy of Sciences, Climate Change Research Center, Beijing (China); Yin, Yizhou [Tsinghua University, Center for Earth System Science, Beijing (China)

    2012-12-15

    This paper addresses the interdecadal variation of the West African summer monsoon (WASM) along with its background of atmospheric circulation and possible physical mechanism over the past 32 years (1979-2010). It is indicated that the WASM starts to strengthen from 1998 as the rainfall begins to increase over western West Africa on the whole, which shows a new interdecadal variation. In this interdecadal variation, the strengthened ascending motion corresponding to enhanced divergence (convergence) movement on the upper (lower) troposphere is prone to develop the local circulation of the monsoon. Moreover, the strengthened southwestern (eastern) wind on the lower (upper) level leads to more moisture from the Atlantic and the Gulf of Guinea transported to the West African continent. In addition, the summer subtropical high over the north Atlantic and western West Africa is strong and northward, and the tropical east wind is also strong. Statistically, the weaker (stronger) the spring North Atlantic Oscillation (NAO) is, the stronger (weaker) the tropical easterly is, and then the WASM is also stronger. But the effect of the NAO on the decadal variation of the WASM is not so significant from the north Atlantic anomaly sensitivity simulation with a single model. This is also an indication that the relationship between the WASM and NAO is complicated in an interdecadal time scale and is needed further study. In terms of sea surface temperature (SST) variation, the tendency is toward warming in the subtropical north Pacific, the south Pacific and north Atlantic. Numerical simulation experiments and data analysis show that the SST variation in the north Pacific plays an important role in the latest interdecadal strengthening of the WASM during the past 32 years, while the influences of the south Pacific and the north Atlantic SST anomalies are not so significant to the associated atmospheric circulation changes. (orig.)

  5. The Mediterranean Water content in the Northeast Atlantic

    Science.gov (United States)

    Nascimento, Angela; Bashmachnikov, Igor; Neves, Filipe

    2014-05-01

    slope, and further gradually decreased to the west and to the south. To the west it reached about 10% at 35-40º W, over the subptropical section of the Mid-Atlantic ridge, and to the south it totally disappeared around 25o N, south of the Canary islands. Following the values of the maximum percentage of the MW, we got that at 700 m depth its preferred path was to the north along the Iberian continental margin and further on, reaching 24% at 45 - 50o N. At 900- 1300 m depth the MW preferably moved west and west-south-west. Below 1500 m level the MW still had a significant percentage and moved south-west.

  6. The 1983 drought in the West Sahel: a case study

    Energy Technology Data Exchange (ETDEWEB)

    Bader, Juergen [Bjerknes Centre for Climate Research, Bergen (Norway); University of Bergen, Geophysical Institute, Bergen (Norway); Latif, Mojib [Leibniz-Institute for Marine Sciences at the University of Kiel, Kiel (Germany)

    2011-02-15

    Some drought years over sub-Saharan west Africa (1972, 1977, 1984) have been previously related to a cross-equatorial Atlantic gradient pattern with anomalously warm sea surface temperatures (SSTs) south of 10 N and anomalously cold SSTs north of 10 N. This SST dipole-like pattern was not characteristic of 1983, the third driest summer of the twentieth century in the Sahel. This study presents evidence that the dry conditions that persisted over the west Sahel in 1983 were mainly forced by high Indian Ocean SSTs that were probably remanent from the strong 1982/1983 El Nino event. The synchronous Pacific impact of the 1982/1983 El Nino event on west African rainfall was however, quite weak. Prior studies have mainly suggested that the Indian Ocean SSTs impact the decadal-scale rainfall variability over the west Sahel. This study demonstrates that the Indian Ocean also significantly affects inter-annual rainfall variability over the west Sahel and that it was the main forcing for the drought over the west Sahel in 1983. (orig.)

  7. 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...

  8. 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...

  9. A Review of ENSO Influence on the North Atlantic. A Non-Stationary Signal

    Directory of Open Access Journals (Sweden)

    Belén Rodríguez-Fonseca

    2016-06-01

    Full Text Available The atmospheric seasonal cycle of the North Atlantic region is dominated by meridional movements of the circulation systems: from the tropics, where the West African Monsoon and extreme tropical weather events take place, to the extratropics, where the circulation is dominated by seasonal changes in the jetstream and extratropical cyclones. Climate variability over the North Atlantic is controlled by various mechanisms. Atmospheric internal variability plays a crucial role in the mid-latitudes. However, El Niño-Southern Oscillation (ENSO is still the main source of predictability in this region situated far away from the Pacific. Although the ENSO influence over tropical and extra-tropical areas is related to different physical mechanisms, in both regions this teleconnection seems to be non-stationary in time and modulated by multidecadal changes of the mean flow. Nowadays, long observational records (greater than 100 years and modeling projects (e.g., CMIP permit detecting non-stationarities in the influence of ENSO over the Atlantic basin, and further analyzing its potential mechanisms. The present article reviews the ENSO influence over the Atlantic region, paying special attention to the stability of this teleconnection over time and the possible modulators. Evidence is given that the ENSO–Atlantic teleconnection is weak over the North Atlantic. In this regard, the multidecadal ocean variability seems to modulate the presence of teleconnections, which can lead to important impacts of ENSO and to open windows of opportunity for seasonal predictability.

  10. The Lagos coast : Investigation of the long-term morphological impact of the Eko Atlantic City project

    NARCIS (Netherlands)

    van Bentum, K.M.; Hoyng, C.W.; van Ledden, M.; Luijendijk, A.P.; Stive, M.J.F.

    2012-01-01

    The Lagos coast has been suffering high rates of erosion since the construction of three harbour moles, i.e. the West Mole, East Mole and the Training Mole, at the tidal inlet connecting the Lagos Lagoon to the South Atlantic Ocean. To provide for a permanent erosion mitigation measure and to create

  11. Palaemon vicinus spec. nov. (Crustacea: Decapoda: Palaemonidae), a new species of caridean shrimp from the tropical eastern Atlantic

    NARCIS (Netherlands)

    Ashelby, C.W.

    2009-01-01

    A new species of Palaemon, P. vicinus spec. nov., is described from the tropical eastern Atlantic. The new species is very close to P. elegans Rathke, 1837, under which name it was previously recorded from West Africa. Palaemon vicinus spec. nov. is easily separated from P. elegans by possessing a

  12. Retention of fish larvae in a fjord system - a seasonal study of the larval life in a West Greenlandic fjord

    DEFF Research Database (Denmark)

    Swalethorp, Rasmus; Munk, Peter; Nielsen, Torkel Gissel

    The Godthåbsfjord is the largest fjord system on the West Greenlandic coast and an important spawning site for several fish species. It houses the largest inshore stock of Atlantic cod (Gadus morhua) on the west coast but also key species like Capelin (Mallotus villosus) and American plaice...... (Hippoglossoides platessoides) are abundant. The innermost part of the fjord branch Kapisigdlit is the principal spawning site for the fjord population of Atlantic cod, and in 2010 a seasonal study was carried out on the early life of this population. Abundance and distribution of this and other occurring fish...

  13. 2014 Mid-Atlantic Telehealth Resource Center Annual Summit

    Directory of Open Access Journals (Sweden)

    Katharine Hsu Wibberly

    2013-12-01

    Full Text Available The Mid-Atlantic Resource Center (MATRC; http://www.matrc.org/ advances the adoption and utilization of telehealth within the MATRC region and works collaboratively with the other federally funded Telehealth Resource Centers to accomplish the same nationally. MATRC offers technical assistance and other resources within the following mid-Atlantic states: Delaware, District of Columbia, Kentucky, Maryland, North Carolina, Pennsylvania, Virginia and West Virginia.   The 2014 MATRC Summit “Adding Value through Sustainable Telehealth” will be held March 30-April 1, 2014, at the Fredericksburg Expo & Conference Center, Fredericksburg, VA. The Summit will explore how telehealth adds value to patients, practitioners, hospitals, health systems, and other facilities. Participants will experience a highly interactive program built around the case history of “Mr. Doe” as he progresses through the primary care, inpatient hospitalization, and post-discharge environments. The Summit will conclude with a session on financial and business models for providing sustainable telehealth services.   For further information and registration, visit: http://matrc.org/component/content/article/2-uncategorised/80-mid-atlantic-telehealth-resource-summit-2014    

  14. Aerosol interactions with African/Atlantic climate dynamics

    International Nuclear Information System (INIS)

    Hosseinpour, F; Wilcox, E M

    2014-01-01

    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. (paper)

  15. The lithospheric mantle below southern West Greenland

    DEFF Research Database (Denmark)

    Sand, Karina Krarup; Waight, Tod Earle; Pearson, D. Graham

    2009-01-01

    Geothermobarometry of primarily garnet lherzolitic xenoliths from several localities in southern West Greenland is applied to address the diamond potential, pressure and temperature distribution and the stratigraphy of the subcontinental lithospheric mantle ~600 Ma ago. The samples are from...... kimberlitic and ultramafic lamprophyre (senso lato) dikes and sills emplaced into three tectonically distinct crustal areas in the North Atlantic Craton. Several geothermobarometry formulations have been applied and a thorough assessment of which P-T combinations are most applicable to this sample suite has...... and the Kirkland Lake locality within the Superior craton. In supporting previous studies we find that the continental lithospheric mantle is layered and increases in fertility with depth. Twenty-five of 32 investigated samples are estimated to be derived from the diamond stability field that extends...

  16. Numerical evaluation of the wave energy resource along the Atlantic European coast

    Science.gov (United States)

    Guedes Soares, C.; Bento, A. Rute; Gonçalves, Marta; Silva, Dina; Martinho, Paulo

    2014-10-01

    In the present paper a hindcast system is applied to the analysis of the Atlantic European coast as a whole with specific nestings for sites of interest in each country. The areas included in this study were: Ireland west coast, UK South Western coast, France west coast, northern Spain and Canary Islands and Portugal's continental coast. Two contemporary spectral models were used: WaveWatch III for wave generation, covering almost the entire North Atlantic basin, which outputs are then used as boundary conditions for SWAN which simulates wave transformation in coastal areas. Wind fields were taken from the ERA Interim data base. Results are validated against buoy data. These validations allowed a reformulation, when needed, of the model's configurations in order to better tune its outcomes to the real data. Using the energy transport vectors given by SWAN, the wave power is afterwards calculated and an energy resource assessment is done for a period of several years.

  17. North Atlantic Energy Structures

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, S. [North Atlantic Energy Structures Inc., St. John' s, NL (Canada); Derradji, A. [National Research Council of Canada, St. John' s, NL (Canada). Inst. for Ocean Technology

    2005-07-01

    North Atlantic Energy Structures Inc. is in the process of designing a tidal fence for a site near the Straits of Belle Isle. This presentation provided details of both the design and the location in which the wave energy plant will be installed. Design constraints included a short seasonal work window, and a harsh but pristine environment. Design specifications of the paddlewheels and caissons were presented. The paddlewheel is iceberg and slab ice resistant, and has portals below the wheel axis, a water-free upper chamber, and bi-directional power generation. The planned installation sequence was presented, as well as details of a hydrodynamic simulation examining torque on the turbines in the tidal energy chamber. Results of the study indicated that 20 paddlewheels per caisson provided the equivalent of 12 MW of energy. A tidal fence of 70 to 80 caissons provided the equivalent of 1.2 GW of energy. A slab ice simulation study was outlined, and details of the pumping station, inlet and hydro-generation station were provided. A map of the proposed siting of the tidal fence was presented. It was concluded that financing for the pilot project has been granted. However, further financing for research and development is required. refs., tabs., figs.

  18. Fathers in hot water: rising sea temperatures and a Northeastern Atlantic pipefish baby boom.

    Science.gov (United States)

    Kirby, Richard R; Johns, David G; Lindley, John A

    2006-12-22

    We report unprecedented numbers of juvenile snake pipefish, Entelurus aequoreus, in continuous plankton records of the Northeastern Atlantic since 2002. Increased sea surface temperatures (SSTs) in the Northern Hemisphere, linked to global warming, are a likely cause. Analysis of a long-term time-series of SST data in the Northeastern Atlantic shows a rise in winter, spring and summer sea temperatures (January-September), when the eggs of E. aqueoreus, which are brooded by the male, are developing and the larvae are growing in plankton. From what is known of the reproductive biology of closely related species, we suggest that the increased abundance of larval and juvenile E. aequoreus in the plankton as far west as the Mid-Atlantic Ridge may reflect the impact of temperature on abundance, through its effects on the operational sex ratio and potential reproductive rate, the onset of the breeding season and juvenile survival in this sex role reversed fish.

  19. West Greenlandic Eskimo

    DEFF Research Database (Denmark)

    Trondhjem, Naja Blytmann; Fortescue, Michael David

    the principal economic activity. Research projects and language initiatives currently in progress within Greenland will be touched upon, as will the possibilities of communication with North American Inuit. West Greenlandic is unique among the native languages of the North American Arctic and Sub......West Greenlandic Eskimo. The current situation of the West Greenlandic language as principal means of communication among the majority Greenlandic population will be presented with special emphasis on the northwest hunting district of Upernavik, where traditional marine mammal hunting is still...

  20. The PIRATA Observing System in the Tropical Atlantic: Enhancements and perspectives

    Science.gov (United States)

    Hernandez, Fabrice; Araujo, Moacyr; Bourlès, Bernard; Brandt, Peter; Campos, Edmo; Giordani, Hervé; Lumpkin, Rick; McPhaden, Michael J.; Nobre, Paulo; Saravanan, Ramalingam

    2017-04-01

    PIRATA (Prediction and Research Moored Array in the Tropical Atlantic) is a multinational program established to improve our knowledge and understanding of ocean-atmosphere variability in the tropical Atlantic, a region that strongly influences the regional hydro-climates and, consequently, the economies of the regions bordering the Atlantic Ocean (e.g. West Africa, North-Eastern Brazil, the West Indies and the United States). PIRATA is motivated not only by fundamental scientific questions but also by societal needs for improved prediction of climatic variability and its impacts. PIRATA, initiated in 1997, is based around an array of moored buoys providing meteorological and oceanographic measurements transmitted in real-time, disseminated via GTS and Global Data Servers. Then, through yearly mooring maintenance, recorded high frequency data are collected and calibrated. The dedicated cruises of yearly maintenance allow complementary acquisition of a large number of measurements along repeated ship track lines and also provide platforms for deployments of other components of the observing system. Several kinds of operations are carried out in collaboration with other international programs. PIRATA provides invaluable data for numerous and varied applications, among which are analyses of climate variability on intraseasonal-to-decadal timescales, equatorial dynamics, mixed-layer temperature and salinity budgets, air-sea fluxes, data assimilation, and weather and climate forecasts. PIRATA is now 20 years old, well established and recognized as the backbone of the tropical Atlantic sustained observing system. Several enhancements have been achieved during recent years, including progressive updating of mooring systems and sensors, also in collaborations with and as a contribution to other programs (such as EU PREFACE and AtlantOS). Recent major accomplishments in terms of air-sea exchanges and climate predictability will be highlighted in this presentation. Future

  1. 76 FR 72383 - Atlantic Highly Migratory Species; Atlantic Shark Management Measures

    Science.gov (United States)

    2011-11-23

    ... Administration 50 CFR Part 635 RIN 0648-BA17 Atlantic Highly Migratory Species; Atlantic Shark Management...) and fishery management plan (FMP) amendment that would consider catch shares for the Atlantic shark... design elements for potential catch shares programs in the Atlantic shark fisheries. Additionally, NMFS...

  2. 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...

  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. 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 (America, west of the Rio Grande fracture zone. This process has lasted until ∼92 Myr ago after which both Africa and South America (south of the equator) behaved rigidly. The clearing of the continental-oceanic boundaries within the Equatorial Atlantic Gateway was probably completed by ∼95 Myr ago. The clearing was followed by a progressive widening and deepening of the passageway, 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.

  5. WEST Physics Basis

    Science.gov (United States)

    Bourdelle, C.; Artaud, J. F.; Basiuk, V.; Bécoulet, M.; Brémond, S.; Bucalossi, J.; Bufferand, H.; Ciraolo, G.; Colas, L.; Corre, Y.; Courtois, X.; Decker, J.; Delpech, L.; Devynck, P.; Dif-Pradalier, G.; Doerner, R. P.; Douai, D.; Dumont, R.; Ekedahl, A.; Fedorczak, N.; Fenzi, C.; Firdaouss, M.; Garcia, J.; Ghendrih, P.; Gil, C.; Giruzzi, G.; Goniche, M.; Grisolia, C.; Grosman, A.; Guilhem, D.; Guirlet, R.; Gunn, J.; Hennequin, P.; Hillairet, J.; Hoang, T.; Imbeaux, F.; Ivanova-Stanik, I.; Joffrin, E.; Kallenbach, A.; Linke, J.; Loarer, T.; Lotte, P.; Maget, P.; Marandet, Y.; Mayoral, M. L.; Meyer, O.; Missirlian, M.; Mollard, P.; Monier-Garbet, P.; Moreau, P.; Nardon, E.; Pégourié, B.; Peysson, Y.; Sabot, R.; Saint-Laurent, F.; Schneider, M.; Travère, J. M.; Tsitrone, E.; Vartanian, S.; Vermare, L.; Yoshida, M.; Zagorski, R.; Contributors, JET

    2015-06-01

    With WEST (Tungsten Environment in Steady State Tokamak) (Bucalossi et al 2014 Fusion Eng. Des. 89 907-12), the Tore Supra facility and team expertise (Dumont et al 2014 Plasma Phys. Control. Fusion 56 075020) is used to pave the way towards ITER divertor procurement and operation. It consists in implementing a divertor configuration and installing ITER-like actively cooled tungsten monoblocks in the Tore Supra tokamak, taking full benefit of its unique long-pulse capability. WEST is a user facility platform, open to all ITER partners. This paper describes the physics basis of WEST: the estimated heat flux on the divertor target, the planned heating schemes, the expected behaviour of the L-H threshold and of the pedestal and the potential W sources. A series of operating scenarios has been modelled, showing that ITER-relevant heat fluxes on the divertor can be achieved in WEST long pulse H-mode plasmas.

  6. US west coast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Aerial surveys are conducted along the US west coast to determine distribution and abundance of endangered leatherback turtles (Dermochelys coriacea), loggerhead...

  7. West African monsoon 2012

    OpenAIRE

    Cornforth, Rosalind J.

    2013-01-01

    Living up to its reputation as a highly variable climate system, the West African Monsoon (WAM) 2012 contrasted strikingly with the previous year. In 2011, the West African rainy season was delayed, patchy, and irregular. In 2012, whilst it was anomalously wet in many area, the Guinea coastal countries and some crucial agricultural regions remained very dry, persisting from the previous year. As a result, 2012 generated the third big food crisis to hit the region in the last seven years. The ...

  8. West Europe Report

    Science.gov (United States)

    1987-03-24

    East Attiki and West Attiki, as well as the Market Inspection Directorate, Traffic Directorate, Immediate Action Directorate, Police Operations...subdirectorates are established in the West Attiki Police Directorate. Seven market inspection branches come under the Market Inspection Directorate...Banca (18) I Organizac . >nes empresari .’flos (19) ’SIMS Seguridad (yn\\ ii £•’*> \\ ■Hfl sodai K UJ r^;-; 26IS1I11 Par,idos (21

  9. 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

  10. West African Journal of Medicine

    African Journals Online (AJOL)

    The West African Journal of Medicine is owned by the West African College of Physicians and the West African College of Surgeons. Aims: The aims of the Journal are: To provide a medium for international dissemination of information about medical science in West Africa and elsewhere. To furnish a means whereby ...

  11. Invasion of the Indo-Pacific blenny Omobranchus punctatus (Perciformes: Blenniidae on the Atlantic Coast of Central and South America

    Directory of Open Access Journals (Sweden)

    Oscar Lasso-Alcalá

    Full Text Available We examined 308 specimens of the Indo-Pacific blenniid Omobranchus punctatus deposited in four museum collections, and analyzed data on their collection locations to assess its invasion on the Atlantic coast of Central and South America. This species occurs in shoreline estuarine and marine habitats in the Indo-West Pacific. Previous sampling and recent records in the Tropical West Atlantic from 1930 to 2004 produced 20 records for: Panamá, Colombia, Venezuela, Trinidad and Brazil. In this work, we provide data on 17 new records for the Gulfs of Venezuela and Paria in Venezuela, as well as four records for Maranhão and Pará states in NE Brazil. The temporal pattern of collections (1930 - 2009 and the proximity of most localities to ports and zones of ship traffic indicate that O. punctatus was initially introduced to the Atlantic by ships travelling from India to Trinidad. Within Brazil the introduction is linked to shipping connected to petroleum platforms. In Maranhão and Pará the introduction may have occurred as a result of fish sheltering in fouling on hulls of ships moving between ports around the mouth of the Amazon River. Alternatively, the spread of this species along of the American coast may reflect the expansion of the range of O. puntactus through larval dispersal in northward flowing currents. We recommend monitoring of this introduced species, and studies of its ecology in West Atlantic areas.

  12. Climate variability in West Greenland during the past 1500 years

    DEFF Research Database (Denmark)

    dos Santos Ribeiro, Sofia Isabel; Moros, Matthias; Ellegaard, Marianne

    2012-01-01

    -surface temperatures in Disko Bay are out-of-phase with Greenland ice-core reconstructed temperatures and marine proxy data from South and East Greenland. This is probably governed by an NAO-type pattern, which results in warmer sea-surface conditions with less extensive sea ice in the area for the later part....... Sea ice cover and primary productivity were identified as the two main factors driving dinoflagellate cyst community changes through time. Our data provide evidence for an opposite climate trend in West Greenland relative to the NE Atlantic region from c. AD 500 to 1050. For the same period, sea...

  13. The summer North Atlantic Oscillation (SNAO) variability on decadal to paleoclimate time scales

    Science.gov (United States)

    Linderholm, H. W.; Folland, C. K.; Zhang, P.; Gunnarson, B. E.; Jeong, J. H.; Ren, H.

    2017-12-01

    The summer North Atlantic Oscillation (SNAO), strongly related to the latitude of the North Atlantic and European summer storm tracks, exerts a considerable influence on European summer climate variability and extremes. Here we extend the period covered by the SNAO from July and August to June, July and August (JJA). As well as marked interannual variability, the JJA SNAO has shown a large inter-decadal change since the 1970s. Decadally averaged, there has been a change from a very positive to a rather negative SNAO phase. This change in SNAO phase is opposite in sign from that expected by a number of climate models under enhanced greenhouse forcing by the late twenty first century. It has led to noticeably wetter summers in North West Europe in the last decade. On interannual to multidecadal timescales, SNAO variability is linked to variations in North Atlantic sea surface temperature (SST): observations and models indicate an association between the Atlantic Multi-decadal Oscillation (AMO) where the cold (warm) phase of the AMO corresponds a positive (negative) phase of the SNAO. Observations also indicate a link with SST in the Gulf Stream region of the North Atlantic where, particularly on decadal time scales, SST warming may favour a more positive phase of the SNAO. Influences of Arctic climate change on North Atlantic and European atmospheric circulation may also exist, particularly reduced sea ice coverage, perhaps favouring the negative phase of the SNAO. A new tree-ring data based JJA SNAO reconstruction extending over the last millennium, as well as climate model output for the same period, enables us to examine the influence of North Atlantic SST and Arctic sea-ice coverage, as well as SNAO impacts on European summer climate, in a long-term, pre-industrial context.

  14. Mapping and characterizing mangrove rice growing environments in West-Africa using remote sensing and secondary data

    NARCIS (Netherlands)

    Adefurin, O.; Hamdy, M; Zwart, S.J.

    2016-01-01

    Rice is one of the major staple foods consumed in Africa and its demand continues to increase as a result of population growth, urbanization and changing diets. Mangrove rice cultivation is of importance along the West-African Atlantic coast from Senegal and Gambia down to Guinea-Bissau,

  15. Islam and the West

    Directory of Open Access Journals (Sweden)

    Mohd. Kamal Hassan

    1997-06-01

    Full Text Available The scientific and technological developments during the 18th and' the 19th centuries ensured material progress of the West, as well as emergence of the West as the dominating power which colonized the rest of the world. During the post-colonial phase, Islam emerged as a revitalized sociopolitical force. This has been mistaken as a threat by the West, and Islam has been portrayed as the "new enemy after the demise of communism. This is partly an effort to establish a Western identity, which is disintegrating due to lack of a challenge; and partly a reflection of the failure of Muslims to realize the social and ethical ideals of Islam.

  16. The great West Road

    CERN Multimedia

    1975-01-01

    From right to centre the 'Nationale 84' relying Meyrin to Saint-Genis. The fence limits Lab I on that side. From bottom the road leading to the double inclined tunnel linking Lab I and Lab II. On the foreground the ISR building (left) and the West Hall (centre).

  17. West Indian Gallery

    Science.gov (United States)

    Ramsaran, J. A.

    1975-01-01

    Reviews the poetry of Derek Walcott, a native of the West Indies, whose new volume 'Another Life' more resembles the poet-artists commentary on a gallery of scenes and portraits in Melvin Tolson's 'The Harlem Gallery' than anything else that has come from the English speaking Caribbean in the post-war period. (Author/JM)

  18. West African Antislavery Movements

    DEFF Research Database (Denmark)

    Hahonou, Eric Komlavi; Pelckmans, Lotte

    2011-01-01

    In the context of liberalization of West African political regimes, the upsurge of audacious political entrepreneurs who want to end chattel slavery in their nation-state, resulted in the legal criminalisation of slavery in both Mauritania (2007) and Niger (2003) and in a proposal to revise...

  19. Hydrography, Surface Geology and Geomorphology of the Deep Water Sedimentary Basins to the West of Ireland

    OpenAIRE

    Vermeulen, N. J.

    1997-01-01

    This desk study involved the assembly, review and analysis of public domain and available data from an extensive deep water area offshore to the west of Ireland. All major bathymetric and sedimentary basins, in addition to associated shallow plateau and bank areas, were considered. Particular emphasis was placed on the Porcupine Seabight and Rockall Trough as these were considered to be the main areas of interest for the proposed 1996 AIRS (Atlantic Irish Regional Survey) project. Only relati...

  20. A Blue BRICS, Maritime Security, and the South Atlantic

    Directory of Open Access Journals (Sweden)

    François Vreÿ

    Full Text Available Abstract Analysts frequently label the BRICS grouping of states (Brazil, India, Russia, China, and South Africa as primarily an economic club emphasising economic performances as primary objectives. Co-operation of international groupings are rarely, if ever, set within the context of their access to maritime interests, security, and benefits. A second void stems from the lack of emphasis upon the economic benefits of secured maritime domains. In this vein, a common, but neglected aspect of the BRICS grouping’s power and future influence resides in their maritime domains, the value of which ultimately depends upon the responsible governance and use of ocean territories. The maritime interests of BRICS countries only become meaningful if reinforced by maritime security governance and co-operation in the respective oceans. Presently China and India seem to dominate the maritime stage of BRICS, but the South Atlantic is an often overlooked space. For BRICS the value of the South Atlantic stems from how it secures and unlocks the potential of this maritime space through co-operative ventures between Brazil, South Africa as a late BRICS partner, and West African littoral states in particular. Unfortunately, BRICS holds its own maritime tensions, as member countries also pursue competing interests at sea.

  1. 77 FR 25144 - Fisheries of the South Atlantic; South Atlantic Fishery Management Council; Public Meetings

    Science.gov (United States)

    2012-04-27

    .... The Council will consider input from the workgroup and workshops during its June meeting in Orlando... Atlantic; South Atlantic Fishery Management Council; Public Meetings AGENCY: National Marine Fisheries... public meeting and public workshop. SUMMARY: The South Atlantic Fishery Management Council (Council) will...

  2. 77 FR 58982 - Fisheries of the South Atlantic; South Atlantic Fishery Management Council; Public Meeting

    Science.gov (United States)

    2012-09-25

    ... the South Atlantic; South Atlantic Fishery Management Council; Public Meeting AGENCY: National Marine... of a public meeting. SUMMARY: The South Atlantic Fishery Management Council (Council) will hold a... October 18, 2012. ADDRESSES: The meeting will be held at the Radisson Resort at the Port, 8701 Astronaut...

  3. 75 FR 44938 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; Atlantic Coastal Shark Fishery

    Science.gov (United States)

    2010-07-30

    ... 0648-XX28 Atlantic Coastal Fisheries Cooperative Management Act Provisions; Atlantic Coastal Shark... cancellation of the Federal moratorium on fishing for Atlantic coastal sharks in the State waters of New Jersey... Sharks (Coastal Shark Plan). DATES: Effective July 30, 2010. ADDRESSES: Emily Menashes, Acting Director...

  4. 75 FR 35432 - Atlantic Highly Migratory Species; North and South Atlantic Swordfish Quotas

    Science.gov (United States)

    2010-06-22

    ... Conservation of Atlantic Tunas (ICCAT) recommendations 09-02 and 09-03, which maintain the U.S. allocation of... fishing for swordfish in the Atlantic Ocean, including the Caribbean Sea and Gulf of Mexico, by.... 1801 et seq., and the Atlantic Tunas Convention Act (ATCA), 16 U.S.C. 971 et seq. Regulations issued...

  5. 75 FR 57407 - Atlantic Highly Migratory Species; North and South Atlantic Swordfish Quotas

    Science.gov (United States)

    2010-09-21

    ... Conservation of Atlantic Tunas (ICCAT) Recommendations 09-02 and 09-03, which maintain the U.S. allocation of... fishing for swordfish in the Atlantic Ocean, including the Caribbean Sea and Gulf of Mexico, by...., and the Atlantic Tunas Convention Act (ATCA), 16 U.S.C. 971 et seq. Regulations issued under the...

  6. Assembling Aarhus West

    DEFF Research Database (Denmark)

    Krogh, Mads

    2017-01-01

    -geographical marginalization into the Danish popular music and cultural mainstream. In this article, I present Aarhus West as a case study to discuss (sub)generic developments within hip hop as a global phenomenon. While considering current developments in popular music genre theory, I argue that predominant notions......Aarhus West rap music constitutes a dominant trend within Danish hip-hop. Throughout the 2000s, a number of rappers with a common background in a specific area in the western part of Aarhus rose to national fame, setting sales records while bringing issues of ethnic and socio...... of “glocalized” rap as ‘resistance vernaculars’ or ‘global noise’ (cf. Hawkins et al. 2004, Mitchell 2001) risk maintaining overly homogenous understandings of genre. In particular, I appeal to the Deleuzian concept of assemblage to highlight heterogeneity – and more specifically continuous de- and re...

  7. The West Heslerton Assessment

    Directory of Open Access Journals (Sweden)

    Dominic Powlesland

    1999-03-01

    Full Text Available The excavation of the Early Anglo-Saxon or Anglian Settlement at West Heslerton, North Yorkshire, between 1986 and 1995, represents one of the largest excavations conducted in Britain in the last two decades. The project, funded by English Heritage, combined the fundamental needs of rescue and research archaeology. The excavation has produced a wealth of new evidence which is forcing us to re-evaluate much that has been said about the formative period of the English nation.

  8. JPRS Report West Europe

    Science.gov (United States)

    1988-08-22

    INFORMATIONSERVICE SPRINGFIELD, VA 22161 Dnc QUALETS rasesQESffl I to Scfi West Europe JPRS- WER-88-045 CONTENTS 22 A UGUST1988 POLITICAL... Europe (without arms or with restrictions on arms). "This latter line, which omits the claim for a nuclear-free zone, expresses a realistic and...notorious person allegedly involved in much-discussed corrupt practices related to the procurement of military equipment. According to certain

  9. West Europe Report

    Science.gov (United States)

    1987-05-26

    ASIA yellow NEAR EAST Q SOUTH ASIA ...blue LATIN AMERICA P*nk WEST EUROPE lvory AFRICA (SUB-SAHARA) tan SCIENCE P, TECHNOLOGY gray WORLUWIDES...in industry and the payment of benefits in a very lucid manner. But there is a much greater problem, a much more sensitive problem, for the CDA as...it a mere desire to gain power that had escaped him? Without question, Gomez had long dreamed of imposing his authority in this sector of weapons

  10. West Virginia Forests 2013

    Science.gov (United States)

    Randall S. Morin; Gregory W. Cook; Charles J. Barnett; Brett J. Butler; Susan J. Crocker; Mark A. Hatfield; Cassandra M. Kurtz; Tonya W. Lister; William G. Luppold; William H. McWilliams; Patrick D. Miles; Mark D. Nelson; Charles H. (Hobie) Perry; Ronald J. Piva; James E. Smith; Jim Westfall; Richard H. Widmann; Christopher W. Woodall

    2016-01-01

    The annual inventory of West Virginia's forests, completed in 2013, covers nearly 12.2 million acres of forest land with an average volume of more than 2,300 cubic feet per acre. This report is based data collected from 2,808 plots located across the State. Forest land is dominated by the oak/hickory forest-type group, which occupies 74 percent of total forest...

  11. JPRS Report, West Europe.

    Science.gov (United States)

    1987-07-31

    064 31 JULY 1987 WEST EUROPE CONTENTS POLITICAL BELGIUM Brugge’s Mayor Van Acker’s Views, Position Examined (Jos Grobben; KNACK, 20 May 87...87) 83 NORWAY Europe Report: Country Must Adapt to EC Internal Market (AFTENPOSTEN, various dates) 88 - c - Country Must Increase Ties...split the party if the executive committee insisted that he be overturned. "He only needs to find a weakling in the group and to bribe him with a

  12. JPRS Report, West Europe

    Science.gov (United States)

    1988-06-16

    Even in the cities of Prato, Carpi, Faenza, Reggio Emilia , and Pesaro, which have a high percentage of artisans and particularly older popu- lations...party cards that vary between 2.5 and 2 percent: Alberto Ciampaglia (Naples), Angelo Tansini ( Emilia West), Bruno Corti (Brescia), Antonio Cariglia...Under 2 percent are Anselmo Martoni ( Emilia East), Paolo Correale (Salerno), Luigi Preti (Ferrara), Alessandro Ghinami (Cagliari), Gianni Moroni (Rieti

  13. West Virginia's Forests 2008

    Science.gov (United States)

    Richard H. Widmann; Gregory W. Cook; Charles J. Barnett; Brett J. Butler; Douglas M. Griffith; Mark A. Hatfield; Cassandra M. Kurtz; Randall S. Morin; W. Keith Moser; Charles H. Perry; Ronald J. Piva; Rachel Riemann; Christopher W. Woodall

    2012-01-01

    The first full annual inventory of West Virginia's forests reports 12.0 million acres of forest land or 78 percent of the State's land area. The area of forest land has changed little since 2000. Of this land, 7.2 million acres (60 percent) are held by family forest owners. The current growing-stock inventory is 25 billion cubic feet--12 percent more than in...

  14. Water mass analysis for the U.S. GEOTRACES (GA03) North Atlantic sections

    Science.gov (United States)

    Jenkins, W. J.; Smethie, W. M.; Boyle, E. A.; Cutter, G. A.

    2015-06-01

    We present the distributions of hydrographic properties (potential temperature, salinity, dissolved oxygen, and micromolar level inorganic macronutrients) along two sections occupied in the subtropical North Atlantic as part of the first U.S. GEOTRACES (GA03) survey during 2010 and 2011. The purpose of this work is to place subsequent papers in this special issue in a general context and to provide a framework in which the observed distributions of Trace Elements and Isotopes can be interpreted. Using these hydrographic properties we use a modified Optimum Multiparameter water mass analysis method to diagnose the relative contributions of various water types along the sections and rationalize their distributions. The water mass compositions appear largely consistent with what is understood from previous studies about the large scale circulation and ventilation of the North Atlantic, with perhaps one exception. We found that the North Atlantic Deep water both east and west of the Mid Atlantic Ridge is more strongly influenced by Iceland Scotland Overflow Water relative to Denmark Straits Overflow Water (about 3:1) than inferred from other tracer studies (typically 2:1). It remains unclear whether this is an artifact of our calculation or a real change in deep water composition in the decades between the determinations.

  15. Modelling teleconnections between the North Atlantic and North Pacific during the Younger Dryas

    Science.gov (United States)

    Mikolajewicz, Uwe; Crowley, Thomas J.; Schiller, Andreas; Voss, Reinhard

    1997-05-01

    Evidence for a cooling event synchronous with the Younger Dryas (12,000 calendar years before present) has been found in the North Pacific Ocean north of 30° N in records of surface1-5 and subsurface water properties6,7. These changes may be related to a temporary shut-down of North Atlantic Deep Water formation and associated surface cooling over the North Atlantic. It has remained unclear, however, whether this North Atlantic cooling was communicated to the North Pacific Ocean through the atmosphere or the ocean. Here we report results of a sensitivity experiment with a coupled ocean-atmosphere general circulation model that support a primarily atmospheric forcing of North Pacific climate variations. Changes in wind strongly affect coastal upwelling at the North American west coast, and surface cooling by the atmosphere causes better ventilation of the thermocline waters of the northeast Pacific. This effect is amplified by oceanic progagation to the Pacific of the signal arising from collapse of North Atlantic Deep Water formation. These teleconnections may also explain earlier North Pacific and western North American millenial-scale cooling events of a similar nature8-12.

  16. Convective Lofting Links Indian Ocean Air Pollution to Recurrent South Atlantic Ozone Maxima

    Science.gov (United States)

    Chatfield, R. B.; Guan, H.; Thompson, A. M.; Witte, J.

    2003-12-01

    We extend on our analysis of equatorial tropospheric ozone to illustrate the contributions of South Asian pollution export in forming episodes of high O3 over the Atlantic Ocean. We amplify on an earlier description of a broad resolution of the "Atlantic Paradox," for the Jan-Feb-March period, which included initial indications of a very long-distance contribution from South Asia. The approach has been to describe typical periods of significant maximum and minimum tropospheric ozone for early 1999, exploiting TOMS tropospheric ozone estimates jointly with characteristic features of the SHADOZ (Southern Hemisphere Additional Ozonesondes) ozone soundings. Further investigation of the Total Tropospheric Ozone (TTO) record for all of 1999 suggests that there are repeated periods of very long-distance Asian influence crossing Africa, with an apparent effect on those portions of the Atlantic Equatorial troposphere which are downwind. Trajectory analyses suggest that the pattern over the Indian Ocean is complex: a sequence invoving multiple or mixed combustion sources, low level transport, cumulonimbus venting, and high-level transport to the west seem to be indicated by the TTO record. Biomass burning, fossil and biofuel combustion, and lighting seem to all contribute. For the Atlantic, burning and lighting on adjacent continents as well as episodes of this cross-Africa long-distance transport are all linked in a coordinated seasonal march: all are related by movement of the sun. However, interseasonal tropical variability related to the Madden-Julian oscillation allows intermittent ozone buildups that depart from the seasonal norm.

  17. Population genetic structure in Atlantic and Pacific Ocean common murres (Uria aalge): Natural replicate tests of post-Pleistocene evolution

    Science.gov (United States)

    Morris-Pocock, J. A.; Taylor, S.A.; Birt, T.P.; Damus, M.; Piatt, John F.; Warheit, K.I.; Friesen, Vicki L.

    2008-01-01

    Understanding the factors that influence population differentiation in temperate taxa can be difficult because the signatures of both historic and contemporary demographics are often reflected in population genetic patterns. Fortunately, analyses based on coalescent theory can help untangle the relative influence of these historic and contemporary factors. Common murres (Uria aalge) are vagile seabirds that breed in the boreal and low arctic waters of the Northern Hemisphere. Previous analyses revealed that Atlantic and Pacific populations are genetically distinct; however, less is known about population genetic structure within ocean basins. We employed the mitochondrial control region, four microsatellite loci and four intron loci to investigate population genetic structure throughout the range of common murres. As in previous studies, we found that Atlantic and Pacific populations diverged during the Pleistocene and do not currently exchange migrants. Therefore, Atlantic and Pacific murre populations can be used as natural replicates to test mechanisms of population differentiation. While we found little population genetic structure within the Pacific, we detected significant east-west structuring among Atlantic colonies. The degree that population genetic structure reflected contemporary population demographics also differed between ocean basins. Specifically, while the low levels of population differentiation in the Pacific are at least partially due to high levels of contemporary gene flow, the east-west structuring of populations within the Atlantic appears to be the result of historic fragmentation of populations rather than restricted contemporary gene flow. The contrasting results in the Atlantic and Pacific Oceans highlight the necessity of carefully considering multilocus nonequilibrium population genetic approaches when reconstructing the demographic history of temperate Northern Hemisphere taxa. ?? 2008 The Authors.

  18. The Teleconnection of the Tropical Atlantic to Indo-Pacific Sea Surface Temperatures on Inter-Annual to Centennial Time Scales: A Review of Recent Findings

    Directory of Open Access Journals (Sweden)

    Fred Kucharski

    2016-02-01

    Full Text Available In this paper, the teleconnections from the tropical Atlantic to the Indo-Pacific region from inter-annual to centennial time scales will be reviewed. Identified teleconnections and hypotheses on mechanisms at work are reviewed and further explored in a century-long pacemaker coupled ocean-atmosphere simulation ensemble. There is a substantial impact of the tropical Atlantic on the Pacific region at inter-annual time scales. An Atlantic Niño (Niña event leads to rising (sinking motion in the Atlantic region, which is compensated by sinking (rising motion in the central-western Pacific. The sinking (rising motion in the central-western Pacific induces easterly (westerly surface wind anomalies just to the west, which alter the thermocline. These perturbations propagate eastward as upwelling (downwelling Kelvin-waves, where they increase the probability for a La Niña (El Niño event. Moreover, tropical North Atlantic sea surface temperature anomalies are also able to lead La Niña/El Niño development. At multidecadal time scales, a positive (negative Atlantic Multidecadal Oscillation leads to a cooling (warming of the eastern Pacific and a warming (cooling of the western Pacific and Indian Ocean regions. The physical mechanism for this impact is similar to that at inter-annual time scales. At centennial time scales, the Atlantic warming induces a substantial reduction of the eastern Pacific warming even under CO2 increase and to a strong subsurface cooling.

  19. The variability of the North Atlantic Oscillation throughout the Holocene

    Science.gov (United States)

    Wassenburg, Jasper; Dietrich, Stephan; Fietzke, Jan; Fohlmeister, Jens; Wei, Wei; Jochum, Klaus Peter; Scholz, Denis; Richter, Detlev; Sabaoui, Abdellah; Lohmann, Gerrit; Andreae, Meinrat; Immenhauser, Adrian

    2013-04-01

    The North Atlantic Oscillation (NAO) has a major impact on Northern Hemisphere winter climate. Trouet et al. (2009) reconstructed the NAO for the last millennium based on a Moroccan tree ring PDSI (Palmer Drought Severity Index) reconstruction and a Scottish speleothem record. More recently, Olsen et al. (2012) extended the NAO record back to 5.2 ka BP based on a lake record from West Greenland. It is, however, well known that the NAO exhibits non-stationary behavior and the use of a single location for a NAO reconstruction may not capture the complete variability. In addition, the imprint of the NAO on European rainfall patterns in the Early and Mid Holocene on (multi-) centennial timescales is still largely unknown. This is related to difficulties in establishing robust correlations between different proxy records and the fact that proxies may not only reflect winter conditions (i.e., the season when the NAO has the largest influence). Here we present a precisely dated, high resolution speleothem δ18O record from NW Morocco covering the complete Early and Mid Holocene. Carbon and oxygen isotopes were measured at a resolution of 15 years. A multi-proxy approach provides solid evidence that speleothem δ18O values reflect changes in past rainfall intensity. The Moroccan record shows a significant correlation with a speleothem rainfall record from western Germany, which covers the entire Holocene (Fohlmeister et al., 2012). The combination with the extended speleothem record from Scotland, speleothem records from north Italy and the NAO reconstruction from West Greenland (Olsen et al., 2012) allows us to study the variability of the NAO during the entire Holocene. The relation between West German and Northwest Moroccan rainfall has not been stationary, which is evident from the changing signs of correlation. The Early Holocene is characterized by a positive correlation, which changes between 9 and 8 ka BP into a negative correlation. Simulations with the state

  20. Environmental radioactivity in the North Atlantic region. The Faroe Islands and Greenland included. 1984

    International Nuclear Information System (INIS)

    Aarkrog, A.; Boelskifte, S.; Buch, E.; Christensen, G.C.; Dahlgaard, H.; Hallstadius, L.; Hansen, H.; Holm, E.

    1985-12-01

    Measurements of fallout radioactivity in the North Atlantic region including the Faroe Islands and Greenland are reported. Strontium-90 and cesium-137 was determined in samples of precipitation, sea water, vegetation, various foodstuffs (including milk in the Faroes) and drinking water. Estimates are given of the mean contents of 90 Sr and 137 Cs in human diet in the Faroes and Greenland in 1984. Results from samplings of surface sea water and seaweed in the Norwegian and Greenland Seas and along the Norwegian and Greenland west coasts are reported. Beside radiocesium and 90 Sr some of these samples have also been anlysed for tritium, polonium, plutonium and americium. Finally technetium-99 data on seaweed samples collected in the North Atlantic region since the beginning of the sixties are presented. (author)

  1. Boulder Deposits on the Southern Spanish Atlantic Coast: Possible Evidence for the 1755 AD Lisbon Tsunami?

    Directory of Open Access Journals (Sweden)

    Dieter Kelletat

    2005-01-01

    Full Text Available Field evidence of visible tsunami impacts in Europe is scarce. This research focused on an analysis of large littoral debris and accompanying geomorphic features and their rela- tionship to a tsunami event at Cabo de Trafalgar, located on the southern Spanish Atlantic coast. Relative dating of weathering features as well as minor bioconstructive forms in the littoral zone suggest the Lisbon tsunami of 1755 AD as the event responsible for the large deposits described. This tsunami had run up heights of more than 19 m and was generated at the Gorringe Bank, located 500 km west off the Cape. Tsunami deposits at Cabo de Tra- falgar are the first boulder deposits identified on the southern Spanish Atlantic coast and are located approximately 250 km southeast of the Algarve coast (Portugal, where other geo- morphic evidence for the Lisbon tsunami has been reported.

  2. Inflow of Atlantic-origin waters to the Barents Sea along glacial troughs

    Directory of Open Access Journals (Sweden)

    Gennady G. Matishov

    2009-09-01

    Full Text Available This paper discusses the role of glacial shelf topography in the formation of general oceanological and biological mechanisms in the Barents Sea. Analysis of geomorphological data and oceanographic observations obtained on board MMBI research vessels in 2001-08 has shown that: fluxes of Atlantic-origin waters pass along glacial troughs; the inflow of Atlantic waters to the Barents Sea from the west increased from 2001 till 2007, although this advection began to weaken in 2008; vertical and horizontal thermohaline gradients intensified during the investigated period; a warm period similar to that of the 1930s was observed in the Barents Sea at the beginning of the 21st century.

  3. Lionfish (Pterois spp. invade the upper-bathyal zone in the western Atlantic

    Directory of Open Access Journals (Sweden)

    Erika Gress

    2017-08-01

    Full Text Available Non-native lionfish have been recorded throughout the western Atlantic on both shallow and mesophotic reefs, where they have been linked to declines in reef health. In this study we report the first lionfish observations from the deep sea (>200 m in Bermuda and Roatan, Honduras, with lionfish observed to a maximum depth of 304 m off the Bermuda platform, and 250 m off West End, Roatan. Placed in the context of other deeper lionfish observations and records, our results imply that lionfish may be present in the 200–300 m depth range of the upper-bathyal zone across many locations in the western Atlantic, but currently are under-sampled compared to shallow habitats. We highlight the need for considering deep-sea lionfish populations in future invasive lionfish management.

  4. Atlantic interdecadal ocean-atmosphere interaction

    International Nuclear Information System (INIS)

    Kushnir, Y.

    1994-01-01

    We study the climatic scale fluctuation of North Atlantic sea surface temperature (SST), and related atmospheric variability. Time series of North Atlantic SST, based on marine observations, display an almost century long swing from cold condition before 1925 to warm conditions between 1930 and the early 1960s, and back to cold conditions after 1965 or so

  5. Sea level anomaly in the North Atlantic and seas around Europe: Long-term variability and response to North Atlantic teleconnection patterns.

    Science.gov (United States)

    Iglesias, Isabel; Lorenzo, M Nieves; Lázaro, Clara; Fernandes, M Joana; Bastos, Luísa

    2017-12-31

    Sea level anomaly (SLA), provided globally by satellite altimetry, is considered a valuable proxy for detecting long-term changes of the global ocean, as well as short-term and annual variations. In this manuscript, monthly sea level anomaly grids for the period 1993-2013 are used to characterise the North Atlantic Ocean variability at inter-annual timescales and its response to the North Atlantic main patterns of atmospheric circulation variability (North Atlantic Oscillation, Eastern Atlantic, Eastern Atlantic/Western Russia, Scandinavian and Polar/Eurasia) and main driven factors as sea level pressure, sea surface temperature and wind fields. SLA variability and long-term trends are analysed for the North Atlantic Ocean and several sub-regions (North, Baltic and Mediterranean and Black seas, Bay of Biscay extended to the west coast of the Iberian Peninsula, and the northern North Atlantic Ocean), depicting the SLA fluctuations at basin and sub-basin scales, aiming at representing the regions of maximum sea level variability. A significant correlation between SLA and the different phases of the teleconnection patterns due to the generated winds, sea level pressure and sea surface temperature anomalies, with a strong variability on temporal and spatial scales, has been identified. Long-term analysis reveals the existence of non-stationary inter-annual SLA fluctuations in terms of the temporal scale. Spectral density analysis has shown the existence of long-period signals in the SLA inter-annual component, with periods of ~10, 5, 4 and 2years, depending on the analysed sub-region. Also, a non-uniform increase in sea level since 1993 is identified for all sub-regions, with trend values between 2.05mm/year, for the Bay of Biscay region, and 3.98mm/year for the Baltic Sea (no GIA correction considered). The obtained results demonstrated a strong link between the atmospheric patterns and SLA, as well as strong long-period fluctuations of this variable in spatial and

  6. The American South in the Atlantic World

    DEFF Research Database (Denmark)

    , emphasizing black and white racial binaries and outdated geographical boundaries, The American South and the Atlantic World seeks larger thematic and spatial contexts. This is the first book to focus explicitly on how contacts with the peoples, cultures, ideas, and economies of the Atlantic World have...... when there is growing emphasis on globalizing southern studies the collection both demonstrates and critiques the value of Atlantic World perspectives on the region. Equally important, the mix of case studies and state-of-the field essays combines the latest historical thinking on the South’s myriad...... Atlantic World connections with the kinds of innovative cultural and literary scholarship associated with developments in the New Southern Studies. Ultimately, the volume reveals that there is still much to be learned about both the Atlantic World and the American South by considering them in tandem...

  7. Climate Variability and Predictability in North West Africa

    Science.gov (United States)

    Baddour, O.; Djellouli, Y.

    2003-04-01

    North West Africa defined here as the area including Morocco, Algeria and Tunisia, it occupies a large territory in North Africa with more than 3.5 Millions KM2. The geographical contrast is very important: while most of the southern part is desert, the northern and north western part exhibits a contrasting geography including large flat areas in the western part of Morocco, northern Algeria and eastern part of Tunisia, And also the formidable Atlas mountains barrier that extends from south west of Morocco toward north west of Tunisia crossing central Morocco and north Algeria.Agriculture is one of major socio-economic activity in the region with an extensive cash-crop for exporting to Europe especially from Morocco and Tunisia. The influence of the recurring droughts during 80s and 90s was very crucial for the economic and societal aspects of the region. In Morocco, severe droughts has caused GDP fluctuation within past 20 years from 10% increase down to negative values in some particular years. Most of weather systems occurs during frontal excursion through the Atlantic and Europe bringing cold air and cloud and precipitation systems. The active precipitation period extends from October to May with almost 80% of the total rainfall. The dry season extends from June to September. Nevertheless some convective clouds develop occasionally during the dry season due to subtropical humid air mass that converge into the region and trigger the convection especially in the high area and Sahara. These less frequent precipitation systems could lead to weather hazards such as flash floods with damage to population and infrastructure. (The example of OURIKA in August 1995 in Morocco). The far south of the region experiences some tropical influence during August period especially in the south of Algeria when the ITCZ can migrate from the SAHEL area to its northernmost position in the region. Recent studies have investigated seasonal rainfall variability and prediction over

  8. What is the source of dust to West Antarctica?

    Science.gov (United States)

    Borunda, A.; Winckler, G.; Goldstein, S. L.; Kaplan, M. R.; Vallelonga, P. T.

    2017-12-01

    Mineral dust in climate archives can be used as a tracer of past atmospheric circulation pathways. By identifying the original source of dust found in a particular archive, we can determine that past storm tracks must have crossed first the source and then, eventually, the sink. Former work has shown that in past cold stages (e.g. the Last Glacial Maximum (LGM) and other even-numbered marine isotope stages), southern South America provided dust to most of the South Atlantic Ocean and East Antarctica. However, the main dust source to West Antarctica was previously unknown. We analyzed Sr, Nd, and Pb isotope geochemical signatures of insoluble dust extracted from LGM and deglacial sections of the recently-acquired WAIS Divide ice core in central West Antarctica. We found that the source of glacial-age dust for West Antarctica is southern South America, mirroring the East Antarctic results. We also observed that local volcanism provides a varying contribution over the same time period. We demonstrate, therefore, that southern South America is the primary dust provider to all of Antarctica during the LGM, and by implication other cold Ice Age climates. We use that information to infer paleo -atmospheric circulation patterns for the Southern Hemisphere.

  9. Genetic diversity and biogeographical patterns of Caulerpa prolifera across the Mediterranean and Mediterranean/Atlantic transition zone

    KAUST Repository

    Varela-Álvarez, Elena

    2015-01-11

    Knowledge of spatial patterns of genetic differentiation between populations is key to understanding processes in evolutionary history of biological species. Caulerpa is a genus of marine green algae, which has attracted much public attention, mainly because of the impacts of invasive species in the Mediterranean. However, very little is known about the ecological and evolutionary history of the Mediterranean native Caulerpa prolifera, a species which is currently found at sites distributed worldwide. C. prolifera provides a good model to explore the patterns of genetic diversity at different scales across the Mediterranean and Atlantic area. This study aims to investigate the biogeographical patterns of diversity and differentiation of C. prolifera in the Mediterranean, with special focus on the Mediterranean/Atlantic transition zone. We used two nuclear (ITS rDNA and the hypervariable microsatellite locus CaPr_J2) and one chloroplast (tufA) DNA markers on samples of C. prolifera from its entire range. Analyses of 51 sequences of the cpDNA tufA of C. prolifera, 87 ITS2 sequences and genotypes of 788 ramets of C. prolifera for the locus CaPr_J2 revealed three different biogeographical areas: West Atlantic, East Atlantic and a larger area representing the Mediterranean, the Mediterranean/Atlantic transition zone and a Pacific site (Bali). It was found out that the Mediterranean/Atlantic transition zone is a biogeographical boundary for C. prolifera. A lack of connectivity was revealed between Atlantic and Mediterranean types, and identical sequences found in the Mediterranean and Indo-Pacific suggest either recent gene flow along the Red Sea connection or a possible ancient Indo-Pacific origin.

  10. Downward particle fluxes of biogenic matter and Saharan dust across the equatorial North Atlantic

    Science.gov (United States)

    Korte, Laura F.; Brummer, Geert-Jan A.; van der Does, Michèlle; Guerreiro, Catarina V.; Hennekam, Rick; van Hateren, Johannes A.; Jong, Dirk; Munday, Chris I.; Schouten, Stefan; Stuut, Jan-Berend W.

    2017-05-01

    Massive amounts of Saharan dust are blown from the coast of northern Africa across the Atlantic Ocean towards the Americas each year. This dust has, depending on its chemistry, direct and indirect effects on global climate which include reflection and absorption of solar radiation as well as transport and deposition of nutrients and metals fertilizing both ocean and land. To determine the temporal and spatial variability of Saharan dust transport and deposition and their marine environmental effects across the equatorial North Atlantic Ocean, we have set up a monitoring experiment using deep-ocean sediment traps as well as land-based dust collectors. The sediment traps were deployed at five ocean sites along a transatlantic transect between north-west Africa and the Caribbean along 12° N, in a downwind extension of the land-based dust collectors placed at 19° N on the Mauritanian coast in Iouîk. In this paper, we lay out the setup of the monitoring experiment and present the particle fluxes from sediment trap sampling over 24 continuous and synchronized intervals from October 2012 through to November 2013. We establish the temporal distribution of the particle fluxes deposited in the Atlantic and compare chemical compositions with the land-based dust collectors propagating to the downwind sediment trap sites, and with satellite observations of Saharan dust outbreaks. First-year results show that the total mass fluxes in the ocean are highest at the sampling sites in the east and west, closest to the African continent and the Caribbean, respectively. Element ratios reveal that the lithogenic particles deposited nearest to Africa are most similar in composition to the Saharan dust collected in Iouîk. Downwind increasing Al, Fe and K contents suggest a downwind change in the mineralogical composition of Saharan dust and indicate an increasing contribution of clay minerals towards the west. In the westernmost Atlantic Ocean, admixture of re-suspended clay

  11. Forests of West Virginia, 2013

    Science.gov (United States)

    Richard H. Widmann

    2014-01-01

    This publication provides an overview of the forest resources in West Virginia based upon inventories conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program of the Northern Research Station. Information about the FIA program is available online at http://fia.fs.fed.us. Since 2004, FIA has implemented an annual inventory in West Virginia. For...

  12. City of West Liberty, Iowa

    Science.gov (United States)

    The EPA is providing notice of a proposed Administrative Penalty Assessment against the City of West Liberty, Iowa, a municipality with a mailing address of 409 North Calhoun Street, West Liberty, IA 52776, for alleged violations of the Clean Water Act.

  13. West African Journal of Radiology

    African Journals Online (AJOL)

    The West African Journal of Radiology is an annual publication and the official organ of the Association of Radiologists of West Africa. The Journal accepts for publication, original work in the Science and Technology of Radiology, clinical case reports, discoveries and engineering design/fabrication reports related to any ...

  14. Temporal energy partitions of Florida extreme sea level events as a function of Atlantic multidecadal oscillation

    Directory of Open Access Journals (Sweden)

    J. Park

    2010-06-01

    Full Text Available An energy-conservative metric based on the discrete wavelet transform is applied to assess the relative energy distribution of extreme sea level events across different temporal scales. The metric is applied to coastal events at Key West and Pensacola Florida as a function of two Atlantic Multidecadal Oscillation (AMO regimes. Under AMO warm conditions there is a small but significant redistribution of event energy from nearly static into more dynamic (shorter duration timescales at Key West, while at Pensacola the AMO-dependent changes in temporal event behaviour are less pronounced. Extreme events with increased temporal dynamics might be consistent with an increase in total energy of event forcings which may be a reflection of more energetic storm events during AMO warm phases. As dynamical models mature to the point of providing regional climate index predictability, coastal planners may be able to consider such temporal change metrics in planning scenarios.

  15. Geothermal investigations in West Virginia

    Energy Technology Data Exchange (ETDEWEB)

    Hendry, R.; Hilfiker, K.; Hodge, D.; Morgan, P.; Swanberg, C.; Shannon, S.S. Jr.

    1982-11-01

    Deep sedimentary basins and warm-spring systems in West Virginia are potential geothermal resources. A temperature gradient map based on 800 bottom-hole temperatures for West Virginia shows that variations of temperature gradient trend northeasterly, parallel to regional structure. Highest temperature gradient values of about 28/sup 0/C/km occur in east-central West Virginia, and the lowest gradients (18/sup 0/C/km) are found over the Rome Trough. Results from ground-water geochemistry indicate that the warm waters circulate in very shallow aquifers and are subject to seasonal temperature fluctuations. Silica heat-flow data in West Virginia vary from about 0.89 to 1.4 HFU and generally increase towards the west. Bouguer, magnetic, and temperature gradient profiles suggest that an ancient rift transects the state and is the site of several deep sedimentary basins.

  16. 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.

  17. 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...

  18. Temperature fluctuations in the Atlantic Ocean

    International Nuclear Information System (INIS)

    Hjoello, Solfrid Saetre

    2005-01-01

    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

  19. Building the energy infrastructure in Atlantic Canada

    International Nuclear Information System (INIS)

    Curry, T.

    2007-01-01

    This paper discusses the energy infrastructure in Atlantic Canada. The energy development is poised to help transform the economy of New Brunswick. Planning for energy projects and supporting infrastructure are under way and regional opportunities are emerging

  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. 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...

  2. Atlantic-THORpex Observing System Test

    Data.gov (United States)

    National Aeronautics and Space Administration — Atlantic - THORpex Observing System Test (ATOST) is part of an international research program to accelerate improvements in the accuracy of 1 to 14 day weather...

  3. 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...

  4. Identifying Important Atlantic Areas for the conservation of Balearic shearwaters: Spatial overlap with conservation areas

    Science.gov (United States)

    Pérez-Roda, Amparo; Delord, Karine; Boué, Amélie; Arcos, José Manuel; García, David; Micol, Thierry; Weimerskirch, Henri; Pinaud, David; Louzao, Maite

    2017-07-01

    Marine protected areas (MPAs) are considered one of the main tools in both fisheries and conservation management to protect threatened species and their habitats around the globe. However, MPAs are underrepresented in marine environments compared to terrestrial environments. Within this context, we studied the Atlantic non-breeding distribution of the southern population of Balearic shearwaters (Puffinus mauretanicus) breeding in Eivissa during the 2011-2012 period based on global location sensing (GLS) devices. Our objectives were (1) to identify overall Important Atlantic Areas (IAAs) from a southern population, (2) to describe spatio-temporal patterns of oceanographic habitat use, and (3) to assess whether existing conservation areas (Natura 2000 sites and marine Important Bird Areas (IBAs)) cover the main IAAs of Balearic shearwaters. Our results highlighted that the Atlantic staging (from June to October in 2011) dynamic of the southern population was driven by individual segregation at both spatial and temporal scales. Individuals ranged in the North-East Atlantic over four main IAAs (Bay of Biscay: BoB, Western Iberian shelf: WIS, Gulf of Cadiz: GoC, West of Morocco: WoM). While most individuals spent more time on the WIS or in the GoC, a small number of birds visited IAAs at the extremes of their Atlantic distribution range (i.e., BoB and WoM). The chronology of the arrivals to the IAAs showed a latitudinal gradient with northern areas reached earlier during the Atlantic staging. The IAAs coincided with the most productive areas (higher chlorophyll a values) in the NE Atlantic between July and October. The spatial overlap between IAAs and conservation areas was higher for Natura 2000 sites than marine IBAs (areas with and without legal protection, respectively). Concerning the use of these areas, a slightly higher proportion of estimated positions fell within marine IBAs compared to designated Natura 2000 sites, with Spanish and Portuguese conservation

  5. Alien smuggling: East to West.

    Science.gov (United States)

    Walsh, J H

    1987-01-01

    This year untold millions of illegal aliens will enter Western Europe, Canada, and the US; in 1986, the US alone made 1.7 million apprehensions. Because of the numbers involved and the hard currency exchanged, alien smuggling has become big business--a lucrative track in desparate human beings. West Germany's open door asylum policy has been a boon to the smugglers, and West Berlin is currently a favored port of entry. The government provides social benefits--apartments, food, a stipend, and clothing--for asylum seekers. Smuggling operations appear to fit 3 categories: 1) state-sponsored alien smugglers, with a sub-category of terrorists; 2) ethnic smugglers with a history of terrorist spinoffs; and 3) independent smugglers, who are profit oriented, and willing to handle ethnic aliens and terrorists. In West Germany, immigration investigations begin at the border. West German officials often know that as they cause the Eastern border to be tightened, the flow will gravitate south toward Austria. Redirecting the trasit of Third Worlders from East Berlin away from West Germany, Sweden, and Denmark will be a stop-gap measure at best. Part of West Germany's immigration problem can be traced to the Basic Law that provides asylum for those who claim persecution (political, racial, ethnic, or religious). Yet, any attempt to change asylum would result in an admission of defeat in the quest for a unified Germany. Should Austria move to tighten its immigration laws, agreements similar to those between East and West Germany will likely follow.

  6. Pathways of high-latitude dust in the North Atlantic

    Science.gov (United States)

    Baddock, Matthew C.; Mockford, Tom; Bullard, Joanna E.; Thorsteinsson, Throstur

    2017-02-01

    The contribution of mineral dust from high-latitude sources has remained an under-examined feature of the global dust cycle. Dust events originating at high latitudes can provide inputs of aeolian sediment to regions lying well outside the subtropical dust belt. Constraining the seasonal variability and preferential pathways of dust from high-latitude sources is important for understanding the potential impacts that the dust may have on wider environmental systems, such as nearby marine or cryospheric domains. This study quantifies dust pathways from two areas exhibiting different emission dynamics in the north and south of Iceland, which is a prominent Northern Hemisphere dust source. The analysis uses air parcel trajectory modelling, and for the first time for high-latitude sources, explicitly links all trajectory simulations to time-specific (meteorological) observations of suspended dust. This approach maximises the potential for trajectories to represent dust, and illustrates that trajectory climatologies not limited to dust can grossly overestimate the potential for dust transport. Preferential pathways emerge that demonstrate the role of Iceland in supplying dust to the Northern Atlantic and sub-Arctic oceans. For dust emitted from northern sources, a dominant route exists to the northeast, into the Norwegian, Greenland and Barents Seas, although there is also potential for delivery to the North Atlantic in summer months. From the southern sources, the primary pathway extends into the North Atlantic, with a high density of trajectories extending as far south as 50°N, particularly in spring and summer. Common to both southern and northern sources is a pathway to the west-southwest of Iceland into the Denmark Strait and towards Greenland. For trajectories simulated at ≤500 m, the vertical development of dust plumes from Iceland is limited, likely due to the stable air masses of the region suppressing the potential for vertical motion. Trajectories rarely

  7. Isopycnal diffusivity in the tropical North Atlantic oxygen minimum zone

    Science.gov (United States)

    Köllner, Manuela; Visbeck, Martin; Tanhua, Toste; Fischer, Tim

    2017-04-01

    Isopycnal diffusivity plays an important role in the ventilation of the Eastern Tropical North Atlantic (ETNA) Oxygen Minimum Zone (OMZ). Lateral tracer transport is described by isopycnal diffusivity and mean advection of the tracer (e.g. oxygen), together they account for up to 70% of the oxygen supply for the OMZ. One of the big challenges is to separate diffusivity from advection. Isopycnal diffusivity was estimated to be Ky=(500 ± 200) m2 s-1 and Kx=(1200 ± 600) m2 s-1 by Banyte et. al (2013) from a Tracer Release Experiment (TRE). Hahn et al. (2014) estimated a meridional eddy diffusivity of 1350 m2 s-1 at 100 m depth decaying to less than 300 m2 s-1 below 800 m depth from repeated ship sections of CTD and ADCP data in addition with hydrographic mooring data. Uncertainties of the estimated diffusivities were still large, thus the Oxygen Supply Tracer Release Experiment (OSTRE) was set up to estimate isopycnal diffusivity in the OMZ using a newly developed sampling strategy of a control volume. The tracer was released in 2012 in the core of the OMZ at approximately 410 m depth and mapped after 6, 15 and 29 months in a regular grid. In addition to the calculation of tracer column integrals from vertical tracer profiles a new sampling method was invented and tested during two of the mapping cruises. The mean eddy diffusivity during OSTRE was found to be about (300 ± 130) m2 s-1. Additionally, the tracer has been advected further to the east and west by zonal jets. We compare different analysis methods to estimate isopycnal diffusivity from tracer spreading and show the advantage of the control volume surveys and control box approach. From the control box approach we are estimating the strength of the zonal jets within the OMZ core integrated over the TRE time period. References: Banyte, D., Visbeck, M., Tanhua, T., Fischer, T., Krahmann, G.,Karstensen, J., 2013. Lateral Diffusivity from Tracer Release Experiments in the Tropical North Atlantic Thermocline

  8. Trade networks in West Africa

    DEFF Research Database (Denmark)

    Walther, Olivier

    2014-01-01

    To date, most of the literature on trade networks in West Africa has considered networks in a metaphorical way. The aim of this paper is to go one step further by showing how social network analysis may be applied to the study of regional trade in West Africa. After a brief review of the literature......, this exploratory paper investigates two main issues related to regional trade. We start by discussing how recent developments in regional trade in West Africa have contributed to challenging the social structure of traders. We then discuss the changes that have affected the spatiality of regional trade by looking...

  9. 76 FR 37788 - Fisheries of the South Atlantic; South Atlantic Fishery Management Council; Public Meeting

    Science.gov (United States)

    2011-06-28

    ... meeting of its Law Enforcement AP in Orlando, FL. DATES: The meeting will take place July 20, 2011. See SUPPLEMENTARY INFORMATION. ADDRESSES: The meeting will be held at the Marriott Renaissance Orlando Hotel, 5445... the South Atlantic; South Atlantic Fishery Management Council; Public Meeting AGENCY: National Marine...

  10. The role of Atlantic-Arctic exchange in North Atlantic multidecadal climate variability

    NARCIS (Netherlands)

    Frankcombe, L.M.; Dijkstra, H.A.

    2011-01-01

    It has recently been suggested that multidecadal variability in North Atlantic sea surface temperature occurs with two dominant periods. In this paper we investigate the origin of these two time scales in a 500 year control run of the GFDL CM2.1 model. We focus on the exchange between the Atlantic

  11. 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.

    2001-01-01

    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

  12. 76 FR 65673 - Atlantic Highly Migratory Species; Atlantic Shark Management Measures; Correction

    Science.gov (United States)

    2011-10-24

    ...-BB29 Atlantic Highly Migratory Species; Atlantic Shark Management Measures; Correction AGENCY: National... Consolidated Highly Migratory Species (HMS) Fishery Management Plan (FMP) via the rulemaking process to rebuild... Tuesday, October 11, 2011. ADDRESSES: The scoping meeting was held at the Dolce Seaview Resort at 401...

  13. 78 FR 54195 - Atlantic Highly Migratory Species; Atlantic Commercial Shark Fisheries

    Science.gov (United States)

    2013-09-03

    ... 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 shark... adjustments, and applies to commercial Atlantic shark permitted vessels. DATES: The quota transfer is...

  14. 77 FR 35357 - Atlantic Highly Migratory Species; Commercial Atlantic Region Non-Sandbar Large Coastal Shark...

    Science.gov (United States)

    2012-06-13

    ...; Commercial Atlantic Region Non-Sandbar Large Coastal Shark Fishery Opening Date AGENCY: National Marine...-sandbar large coastal shark fishery. This action is necessary to inform fishermen and dealers about the fishery opening date. DATES: The commercial Atlantic region non-sandbar large coastal shark fishery will...

  15. 78 FR 28758 - Atlantic Highly Migratory Species; North and South Atlantic 2013 Commercial Swordfish Quotas

    Science.gov (United States)

    2013-05-16

    ... International Commission for the Conservation of Atlantic Tunas (ICCAT) Recommendations 11-02 and 12-01. This..., including the Caribbean Sea and Gulf of Mexico. This action implements ICCAT recommendations, consistent with the Atlantic Tunas Convention Act (ATCA), and furthers domestic management objectives under the...

  16. 78 FR 20258 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Science.gov (United States)

    2013-04-04

    ... Species; Atlantic Bluefin Tuna Fisheries AGENCY: National Marine Fisheries Service (NMFS), National... Atlantic bluefin tuna (BFT) daily retention limit that applies to vessels permitted in the Highly Migratory... 73 inches). This retention limit is effective in all areas, except for the Gulf of Mexico, where NMFS...

  17. 77 FR 45273 - Atlantic Highly Migratory Species; North and South Atlantic Swordfish Quotas and Management Measures

    Science.gov (United States)

    2012-07-31

    ... Tunas (Commission) Recommendation 11-02, which maintains the U.S. North Atlantic swordfish base quota... Caribbean Sea and Gulf of Mexico. DATES: Effective on August 30, 2012. ADDRESSES: Copies of the supporting... (Magnuson-Stevens Act), and the Atlantic Tunas Convention Act (ATCA). Under ATCA, the Secretary shall...

  18. 76 FR 2640 - Fisheries of the Northeastern United States; Atlantic Bluefish Fishery; 2011 Atlantic Bluefish...

    Science.gov (United States)

    2011-01-14

    ... information about fishery participation in South Carolina, Georgia, or Florida. South Atlantic Trip Ticket... Northeast dealer reports and South Atlantic Trip Ticket reports. Under Alternative 1, the recommended... percent had gross sales of $1,000 or less, and 80 percent had gross sales of $10,000 or less. This likely...

  19. 76 FR 47563 - Fisheries of the South Atlantic; Southeast Data, Assessment, and Review (SEDAR); South Atlantic...

    Science.gov (United States)

    2011-08-05

    ... Outlet Boulevard, North Charleston, SC 29418, telephone: (843) 740-7028. FOR FURTHER INFORMATION CONTACT... unchanged. The Gulf of Mexico, South Atlantic, and Caribbean Fishery Management Councils, in conjunction... Workshops are appointed by the Gulf of Mexico, South Atlantic, and Caribbean Fishery Management Councils and...

  20. DMD and West syndrome.

    Science.gov (United States)

    Cardas, Ruxandra; Iliescu, Catrinel; Butoianu, Nina; Seferian, Andreea; Gataullina, Svetlana; Gargaun, Elena; Nectoux, Juliette; Bienvenu, Thierry; Craiu, Dana; Gidaro, Teresa; Servais, Laurent

    2017-10-01

    Duchenne Muscular Dystrophy (DMD) is the most frequent muscular dystrophy in childhood, with a worldwide incidence of one in 5000 live male births. It is due to mutations in the dystrophin gene leading to absence of full-length dystrophin protein. Central nervous system involvement is well-known in Duchenne Muscular Dystrophy. The multiple dystrophin isoforms expressed in brain have important roles in cerebral development and functioning. The association of Duchenne Muscular Dystrophy with seizures has been reported, and there is a higher prevalence of epilepsy in Duchenne Muscular Dystrophy patients (between 6.3% and 12.3%) than in the general pediatric population (0.5-1%). Duchenne Muscular Dystrophy patients may present with focal seizures, generalized tonic-clonic seizures or absences. We report on two boys in whom Duchenne Muscular Dystrophy is associated with epileptic spasms and hypsarrhythmia that fulfil the criteria for West syndrome, thus extending the spectrum of seizure types described in Duchenne Muscular Dystrophy patients. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Nutrient-driven poleward expansion of the Northeast Atlantic mackerel (Scomber scombrus stock: A new hypothesis

    Directory of Open Access Journals (Sweden)

    Selma V. Pacariz

    2016-05-01

    Full Text Available Abstract The Northeast Atlantic mackerel (Scomber scombrus stock has increased and expanded its summer feeding migration west- and northwards since 2006, entailing large geopolitical challenges for the countries harvesting this species. A common perspective is that climatic warming opens up new regions for biota in the north. It has also been suggested that the presently large pelagic fish stocks deplete prey resources in the eastern North Atlantic during their summer feeding phase, forcing the stocks west towards the Irminger Sea in their search for food. Here, we suggest that the declining nutrient (silicate concentrations observed along the northern European continental slope reduce primary and thus secondary production, exacerbating food scarceness in the east and adding to the incentive to migrate westward. The new westward feeding route requires that the fish cross the Iceland Basin, which during the summer season quickly becomes nutrient-depleted and thus might act as a barrier to migration after the spring bloom. Using mackerel and zooplankton abundance data from the International Ecosystem Summer Surveys in the Nordic Seas, we suggest that the oligotrophic waters in the central Iceland Basin force the fish to migrate through a narrow ‘corridor’ along the south Iceland shelf, where nutrients are replenished and both primary and secondary production are higher.

  2. Radium-226 and barium as tracers of water masses in the North Atlantic (GA01-GEOTRACES)

    Science.gov (United States)

    Le Roy, Emilie; Sanial, Virginie; Charette, Matthew; Henderson, Paul; Jacquet, Stéphanie; García-Ibáñez, Maribel; Pérez, Fiz; Lherminer, Pascale; Souhaut, Marc; Jeandel, Catherine; Lacan, François; van Beek, Pieter

    2017-04-01

    In this study, we report concentrations of radium-226 (226Ra, t1/2=1602 y) and barium determined along the GEOVIDE section conducted in the North Atlantic (May-July 2014; Portugal-Greenland-Canda) in the framework of the international GEOTRACES program. A high vertical resolution (up to 22 depths per station) was achieved by analyzing small volumes (˜10 L) of seawater for 226Ra using a radon emanation technique. We will present the distribution of 226Ra activities and barium concentrations in contrasting biogeochemical regions of the North Atlantic (Iberian margin, West European Basin, Reykjanes Ridge, Irminger Sea, Greenland margin and Labrador Sea). These regions strongly differ in terms of boundary inputs, biogeochemistry and deep water formation. We observe a linear correlation between 226Ra and barium along the GEOVIDE section, which results from the dominantly conservative behavior of the two tracers. However, deviations from the linear correlation between 226Ra and Ba are found in several places. The potential causes for such deviations are investigated. Optimum multi-parameter (OMP) analysis was thus used to distinguish the relative importance of physical transport (i.e., water mass mixing) from non-conservative processes (sedimentary, river or hydrothermal inputs; uptake by particles) on the 226Ra and Ba distribution in the North Atlantic.

  3. A Detailed Assessment of the Wave Energy Resource at the Atlantic Marine Energy Test Site

    Directory of Open Access Journals (Sweden)

    Reduan Atan

    2016-11-01

    Full Text Available Wave characteristic assessments of wave energy test sites provide a greater understanding of prevailing wave conditions and are therefore extremely important to both wave energy test site operators and clients as they can inform wave energy converter design, optimisation, deployment, operation and maintenance. This research presents an assessment of the wave resource at the Atlantic Marine Energy Test Site (AMETS on the west coast of Ireland based on 12-years of modelled data from January 2004 to December 2015. The primary aim is to provide an assessment of annual and seasonal wave characteristics and resource variability at the two deployment berths which comprise the site. A nested model has been developed using Simulating WAves Nearshore (SWAN to replicate wave propagations from regional to local scale with a 0.05° resolution model covering the northeast Atlantic and a 0.0027° resolution model covering AMETS. The coarse and fine models have been extensively validated against available measured data within Irish waters. 12-year model outputs from the high resolution model were analysed to determine mean and maximum conditions and operational, high and extreme event conditions for significant wave height, energy period and power. Annual and seasonal analyses are presented. The 12-year annual mean P were 68 kW/m at Berth A (BA and 57 kW/m at Berth B (BB. The resource shows strong seasonal and annual variations and the winter mean power levels were found to be strongly correlated with the North Atlantic Oscillation (NAO.

  4. Brazilian Policy and the Creation of a Regional Security Complex in the South Atlantic: Pax Brasiliana?

    Directory of Open Access Journals (Sweden)

    Beatriz Rodrigues Bessa Mattos

    Full Text Available Abstract Over the past five years, the South Atlantic region has become a central element of Brazilian security policy, with Brazil actively supporting the notion of a trans-oceanic security consciousness involving African littoral states. It has invested in diplomatic initiatives such as the Zone of Peace and Cooperation of the South Atlantic (ZPCSA, or ZOPACAS, and extensive military co-operation with West African states such as São Tomé e Príncipe, Namibia and Cape Verde. Its internal security and defence policy documents have repeatedly been updated to reflect this dimension, and now provide the foundation for advancing these initiatives. This policy thrust is directed at securing Brazil’s offshore oil assets, and limiting the influence of what it has termed ‘extra-regional powers’ such as the P-5. This article highlights these initiatives and reviews the prospects for this policy by examining the plausibility of the South Atlantic region as a regional security complex in the sense coined by Buzan and Wæver. The analysis is based on the role of geographical and linguistic proximity in international relations, and the impact of multilateral bodies on building support for a regional approach to security governance.

  5. Identification of an assembly site for migratory and tropical seabirds in the South Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    B. John Hughes

    2015-07-01

    Full Text Available Seabirds are good indicators of wider biodiversity and where they assemble in large numbers signifies sites important to many marine faunal species. Few such large assemblage sites have been identified and none in pelagic waters has been identified in the tropical Atlantic Ocean despite their importance for resident seabirds and those ‘on passage’ during migration. Here, we identify the likely location of just such an assembly site and provide preliminary information about the distribution of pelagic seabirds around Ascension Island in the tropical South Atlantic Ocean using a combination of trans-equatorial seabird migrant tracking data, records of at-sea surveys and land counts of seabirds returning from foraging trips. We found that waters north–north-west of Ascension Island are used more often by seabirds than those south and east of the island. Three-fifths of the species recorded in the assembly site breed at mid- or high-latitudes and some of these migratory seabirds stopover possibly to wait for favourable winds that facilitate onward flight. Our findings are important because to the best of our knowledge no seabird assembly sites have previously been identified in tropical Atlantic Ocean pelagic waters. We provide evidence to support the aspirations of the Marine Reserves Coalition that waters in the vicinity of Ascension Island should be recognised as a sanctuary for marine wildlife and we highlight an area that is worthy of further targeted investigation.

  6. WRF/ARPEGE-CLIMAT simulated climate trends over West Africa

    Science.gov (United States)

    Vigaud, N.; Roucou, P.; Fontaine, B.; Sijikumar, S.; Tyteca, S.

    2011-03-01

    The Weather Regional Forecast (WRF) model is used in this study to downscale low-resolution data over West Africa. First, the performance of the regional model is estimated through contemporary period experiments (1981-1990) forced by ARPEGE-CLIMAT GCM output (ARPEGE) and ERA-40 re-analyses. Key features of the West African monsoon circulation are reasonably well represented. WRF atmospheric dynamics and summer rainfall compare better to observations than ARPEGE forcing data. WRF simulated moisture transport over West Africa is also consistent in both structure and variability with re-analyses, emphasizing the substantial role played by the West African Monsoon (WAM) and African Easterly Jet (AEJ) flows. The statistical significance of potential climate changes for the A2 scenario between 2032 and 2041 is enhanced in the downscaling from ARPEGE by the regional experiments, with substantial rainfall increases over the Guinea Gulf and eastern Sahel. Future scenario WRF simulations are characterized by higher temperatures over the eastern Tropical Atlantic suggesting more evaporation available locally. This leads to increased moisture advection towards eastern regions of the Guinea Gulf where rainfall is enhanced through a strengthened WAM flow, supporting surface moisture convergence over West Africa. Warmer conditions over both the Mediterranean region and northeastern Sahel could also participate in enhancing moisture transport within the AEJ. The strengthening of the thermal gradient between the Sahara and Guinean regions, particularly pronounced north of 10°N, would support an intensification of the AEJ northwards, given the dependance of the jet to the position/intensity of the meridional gradient. In turn, mid-tropospheric moisture divergence tends to be favored within the AEJ region supporting southwards deflection of moist air and contributing to deep moist convection over the Sahel where late summer rainfall regimes are sustained in the context of the A2

  7. WRF/ARPEGE-CLIMAT simulated climate trends over West Africa

    Energy Technology Data Exchange (ETDEWEB)

    Vigaud, N.; Roucou, P.; Fontaine, B. [UMR 5210 CNRS, Universite de Bourgogne, Centre de Recherches de Climatologie, Dijon (France); Sijikumar, S. [Space Physics Laboratory, Vikram Sarabhai Space Center, Trivandrum (India); Tyteca, S. [CNRM/GAME, URA 1357 CNRS/Meteo-France, Toulouse (France)

    2011-03-15

    The Weather Regional Forecast (WRF) model is used in this study to downscale low-resolution data over West Africa. First, the performance of the regional model is estimated through contemporary period experiments (1981-1990) forced by ARPEGE-CLIMAT GCM output (ARPEGE) and ERA-40 re-analyses. Key features of the West African monsoon circulation are reasonably well represented. WRF atmospheric dynamics and summer rainfall compare better to observations than ARPEGE forcing data. WRF simulated moisture transport over West Africa is also consistent in both structure and variability with re-analyses, emphasizing the substantial role played by the West African Monsoon (WAM) and African Easterly Jet (AEJ) flows. The statistical significance of potential climate changes for the A2 scenario between 2032 and 2041 is enhanced in the downscaling from ARPEGE by the regional experiments, with substantial rainfall increases over the Guinea Gulf and eastern Sahel. Future scenario WRF simulations are characterized by higher temperatures over the eastern Tropical Atlantic suggesting more evaporation available locally. This leads to increased moisture advection towards eastern regions of the Guinea Gulf where rainfall is enhanced through a strengthened WAM flow, supporting surface moisture convergence over West Africa. Warmer conditions over both the Mediterranean region and northeastern Sahel could also participate in enhancing moisture transport within the AEJ. The strengthening of the thermal gradient between the Sahara and Guinean regions, particularly pronounced north of 10 N, would support an intensification of the AEJ northwards, given the dependance of the jet to the position/intensity of the meridional gradient. In turn, mid-tropospheric moisture divergence tends to be favored within the AEJ region supporting southwards deflection of moist air and contributing to deep moist convection over the Sahel where late summer rainfall regimes are sustained in the context of the A2

  8. 78 FR 57534 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic

    Science.gov (United States)

    2013-09-19

    ... lobster, South Atlantic coral, South Atlantic snapper-grouper, South Atlantic shrimp, Atlantic dolphin and... installation, use, operation, or maintenance of a vessel monitoring system (VMS) unit or communication service...

  9. Influence of the Atlantic subpolar gyre on the thermohaline circulation.

    Science.gov (United States)

    Hátún, Hjálmar; Sandø, Anne Britt; Drange, Helge; Hansen, Bogi; Valdimarsson, Hedinn

    2005-09-16

    During the past decade, record-high salinities have been observed in the Atlantic Inflow to the Nordic Seas and the Arctic Ocean, which feeds the North Atlantic thermohaline circulation (THC). This may counteract the observed long-term increase in freshwater supply to the area and tend to stabilize the North Atlantic THC. Here we show that the salinity of the Atlantic Inflow is tightly linked to the dynamics of the North Atlantic subpolar gyre circulation. Therefore, when assessing the future of the North Atlantic THC, it is essential that the dynamics of the subpolar gyre and its influence on the salinity are taken into account.

  10. A phylogeographic investigation of the kelp genus Laminaria (Laminariales, Phaeophyceae), with emphasis on the South Atlantic Ocean.

    Science.gov (United States)

    Rothman, Mark D; Mattio, Lydiane; Anderson, Robert J; Bolton, John J

    2017-08-01

    The genus Laminaria has a wide distribution range compared with other kelp genera because it is found in both the North and the South Atlantic, on both sides of the North Pacific, as well as in the Mediterranean. Hypotheses behind this biogeographical pattern have been discussed by several authors but have not yet been fully evaluated with time-calibrated phylogenies. Based on the analysis of four molecular markers (ITS2, rbcL, atp8 and trnWI), our goal was to reassess the Laminaria species diversity in South Africa, assess its relationship with the other species distributed in the South Atlantic and reconstruct the historical biogeography of the genus. Our results confirm the occurrence of a single species, L. pallida, in southern Africa, and its sister relationship with the North Atlantic L. ochroleuca. Both species belonged to a clade containing the other South Atlantic species: L. abyssalis from Brazil, and the Mediterranean L. rodriguezii. Our time-calibrated phylogenies suggest that Laminaria originated in the northern Pacific around 25 mya, followed by at least two migration events through the Bering Strait after its opening (~5.32 mya). Today, the first is represented by L. solidungula in the Arctic, while the second gave rise to the rest of the Atlantic species. The colonization of the North Atlantic was followed by a gradual colonization southward along the west coast of Europe, into the Mediterranean (~2.07 mya) and two recent, but disconnected, migrations (~1.34 and 0.87 mya) across the equator, giving rise to L. abyssalis in Brazil and L. pallida in southern Africa, respectively. © 2017 Phycological Society of America.

  11. WEST AFRICAN JOURNAL OF MEDICINE

    African Journals Online (AJOL)

    Urgence, Services d'Ambulances,. Traumatisme, Lagos, Nigeria. WEST AFRICAN JOURNAL OF MEDICINE. ORIGINAL ARTICLE. ABSTRACT. BACKGROUND: Emergency medical care is designed to overcome the factors most commonly implicated ...

  12. West Virginia 511 feasibility study.

    Science.gov (United States)

    2011-06-01

    Procedure for requesting a copy of the full report : Please submit your request, in writing, directly to the contact provided below. : Director of the Traffic Engineering Division : West Virginia Department of Transportation, Division of Highways : B...

  13. [Hormonal treatment in West syndrome].

    Science.gov (United States)

    Belousova, E D; Shulyakova, I V; Ohapkina, T G

    2016-01-01

    West syndrome is one of the most well-known epileptic encephalopathies, a catastrophic epilepsy syndrome with onset in the first year of life. Prognosis of this condition depends on the etiology and adequate treatment. The authors review the hormonal treatment of West syndrome. Adrenocorticotrophic hormone (ACTH) is used in USA and its synthetic analogue tetracosactide is used in Europe. Both of the drugs are not registered in the Russian Federation. The data on the efficacy of corticosteroids, including prednisolone, are contradictory. Recent results have demonstrated the high efficacy of prednisolone in the treatment of West syndrome. The authors discuss different aspects of hormonal treatment of West syndrome: possible mechanisms, choice of medication, hormone doses, its duration, efficacy ant tolerability.

  14. New records of Pennatulacea (Anthozoa: Octocorallia from the African Atlantic coast, with description of a new species and a zoogeographic analysis

    Directory of Open Access Journals (Sweden)

    Pablo J. López-González

    2001-03-01

    Full Text Available A collection of pennatulaceans from ten cruises, acquired between 1982 and 1989 from off the western African coast comprises ca. 350 specimens of 13 species. One of the cruise is from the Gulf of Guinea and eight from the Southeast Atlantic. Fifty-four stations were sampled from depths of 91-1112 m. One previously undescribed species in the genus Stylatula is reported and described as new from samples collected from the Namibian continental shelf. Considering these collections, and previous records, the pennatulaceans in the western African region show biogeographic affinities with three geographic areas: West Africa (55.5% of the species, which comprises the Canary, Gulf of Guinea, and Benguela regions; the North Atlantic (3.7% of the species, which represents the more widespread Atlantic taxa; and Cape Endemic (7.4% of the species, which comprises the southern African region.

  15. 21 CFR 808.98 - West Virginia.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false West Virginia. 808.98 Section 808.98 Food and... and Local Exemptions § 808.98 West Virginia. (a) The following West Virginia medical device... has exempted them from preemption: West Virginia Code, sections 30-26-14 (b) and (c) and section 30-26...

  16. West syndrome: response to valproate.

    Science.gov (United States)

    Chandra, Surabhi; Bhave, Anupama; Bhargava, Roli; Kumar, Chandrakanta; Kumar, Rashmi

    2012-01-01

    Management of West syndrome is unsatisfactory. In our clinic we observed that a significant proportion of patients respond to usual dose of valproate. To prospectively assess the efficacy of valproate in controlling infantile spasms in West syndrome. Consecutive patients presenting with West syndrome to the Pediatric Neurology Clinic or general outpatient department (OPD) were enrolled for study. Those who were not on any treatment were given valproate in a dose of 30 mg/kg/day while awaiting investigations. Patients were followed up every 2 weeks. Predefined criteria for definition of West syndrome and response were used. Those showing partial/poor response or relapse on valproate were given hormonal therapy. One hundred children with West syndrome were enrolled. Ninety one children were started on valproate. Of these 36 (39.5%) showed a good response, but seven later relapsed while on same dose of valproate and three were lost to follow up. Later age at onset and typical hypsarrhythmia on EEG were associated with good sustained response to valproate while a history of delayed cry at birth was associated with partial or poor response. Sixty two patients who responded poorly to or relapsed on valproate were put on hormonal treatment in addition. Of these 36 (58.1%) had a good response but 11 later relapsed after stopping treatment and two were lost to follow up. Valproate may have a role in treatment of West syndrome in a selected group of patients.

  17. West Syndrome: Response to valproate

    Directory of Open Access Journals (Sweden)

    Surabhi eChandra

    2012-11-01

    Full Text Available Management of West syndrome is unsatisfactory. In our clinic we observed that a significant proportion of patients respond to usual dose of valproate. Objective: To prospectively assess the efficacy of valproate in controlling infantile spasms in West syndromeMethods: Consecutive patients presenting with West syndrome to the Pediatric Neurology Clinic or general OPD were enrolled for study. Those who were not on any treatment were given valproate in a dose of 30 mg/kg/day while awaiting investigations. Patients were followed up every 2 weeks. Predefined criteria for definition of West syndrome and response were used. Those showing partial/poor response or relapse on valproate were given hormonal therapy.Results: One hundred children with West syndrome were enrolled. Ninety one children were started on valproate. Of these 36 (39.5% showed a good response, but 7 later relapsed while on same dose of valproate and 3 were lost to follow up. Later age at onset and typical hypsarrythmia on EEG were associated with good sustained response to valproate while a history of delayed cry at birth was associated with partial or poor response. Sixty two patients who responded poorly to or relapsed on valproate were put on hormonal treatment in addition. Of these 36 (58.1% had a good response but 11 later relapsed after stopping treatment and 2 were lost to follow up. Conclusions: Valproate may have a role in treatment of West syndrome in a selected group of patients.

  18. Response of arid ecosystems to the Holocene climate variability along west and central Mediterranean gradients.

    Science.gov (United States)

    Jaouadi, Sahbi; Combourieu Nebout, Nathalie; Azuara, Julien; Lebreton, Vincent

    2017-04-01

    Decadal to millennial climate variability is a common feature recorded by environmental series. However interconnections between climate forcing (i.e. insolation, thermohaline circulation) and large atmospheric circulation patterns (i.e. North Atlantic Oscillation, Mediterranean Oscillation, Monsoon) still remain poorly understood considering their respective impacts on the global climate mechanisms. In the Mediterranean area, joint climatic influences from high temperate and low subtropical latitudes result in a high sensitivity of ecosystems to climate changes and especially to extreme events. Several vegetation records illustrate millennial changes in Mediterranean. Nevertheless notable discrepancies in the environmental response arise between Mediterranean edges (east vs west, north vs south). The new paleoenvironmental record from Sebkha Boujmel (33°N, southern Tunisia) covers the last 8kyr and exhibits eight humid/arid fluctuations with cyclic expansion of the desert, related to Middle and Late Holocene rapid climate changes (RCC) occurring at a centennial scale. Sebkha Boujmel record is replaced in the wider context of west Mediterranean and northern hemisphere. Asynchronies and disparity of the Mediterranean RCC occurrence documents north-south and west-east climate gradients in the west Mediterranean and pinpoint Sebkha Boujmel as the single vegetation record tracing as many climate events during the last 8kyr. Indeed the high sensitivity of arid environments triggers the prompt reaction of the southern Tunisian vegetation to Holocene RCC however tenuous. Pattern of RCC geographical occurrence in west and central Mediterranean is interpreted in the light of climate forcings involved for the Holocene centennial variability.

  19. Why the West?

    Directory of Open Access Journals (Sweden)

    Marc Ferguson

    2009-03-01

    Full Text Available La cuestión de cómo "Occidente" llegó a dominar el mundo durante la era moderna se ha debatido recientemente entre los historiadores. El debate se ha polarizado entre quienes ven en la "modernidad" como resultado de un 'milagro', el proceso cultural único generado en el seno del mismo Occidente, y aquellos que cuestionan este "milagro" como paradigma eurocéntrico, y buscan otros factores para entender y explicar el dominio occidental del mundo económico y político. La literatura tradicional, representada por David Landes en su reciente “La riqueza y la pobreza de las naciones”, atribuye el éxito europeo a sus valores culturales únicos, a sus instituciones sociales y sus prácticas políticas. Este éxito fue completamente "impulsado desde dentro” por estas características. Recientemente, varios historiadores han cuestionado este "paradigma del milagro" como eurocéntrica, y miran a otros factores para comprender y explicar el dominio occidental del mundo económico y político. Después de examinar los recientes trabajos de los historiadores frente a este problema, este artículo trata de colocar la expansión europea en un contexto global, y la comprensión de la Revolución Industrial como una transformación global. Esta perspectiva nos permite entender los cambios tecnológicos y económicos Europeos en el contexto más amplio de patrones de interacción económica y cultural de todo el mundo._____________ABSTRACT:The question of how 'the West' came to dominate the globe during the modern era has been debated recently among historians. The debate has been polarized between those who view 'modernity' as the result of a 'European miracle', the culturally unique and internally generated project of the West, and those who question this 'European miracle' paradigm as Eurocentric, and look to other factors to understand and explain Western economic and political world dominance. The traditional narrative, represented by David

  20. Seasonal predictability of the North Atlantic Oscillation

    Science.gov (United States)

    Vellinga, Michael; Scaife, Adam

    2015-04-01

    Until recently, long-range forecast systems showed only modest levels of skill in predicting surface winter climate around the Atlantic Basin and associated fluctuations in the North Atlantic Oscillation at seasonal lead times. Here we use a new forecast system to assess seasonal predictability of winter North Atlantic climate. We demonstrate that key aspects of European and North American winter climate and the surface North Atlantic Oscillation are highly predictable months ahead. We demonstrate high levels of prediction skill in retrospective forecasts of the surface North Atlantic Oscillation, winter storminess, near-surface temperature, and wind speed, all of which have high value for planning and adaptation to extreme winter conditions. Analysis of forecast ensembles suggests that while useful levels of seasonal forecast skill have now been achieved, key sources of predictability are still only partially represented and there is further untapped predictability. This work is distributed under the Creative Commons Attribution 3.0 Unported License together with an author copyright. This license does not conflict with the regulations of the Crown Copyright.

  1. Changes in the interannual SST-forced signals on West African rainfall. AGCM intercomparison

    Energy Technology Data Exchange (ETDEWEB)

    Mohino, Elsa [LOCEAN/IPSL, Universite Pierre et Marie Curie, Paris Cedex 05 (France); Universidad de Sevilla, Sevilla (Spain); Rodriguez-Fonseca, Belen [Universidad Complutense de Madrid, Dpto. Geofisica y Meteorologia, Madrid (Spain); Instituto de Geociencias (CSIC-UCM), Madrid (Spain); Losada, Teresa [Universidad Complutense de Madrid, Dpto. Geofisica y Meteorologia, Madrid (Spain); Gervois, Sebastien [LOCEAN/IPSL, Universite Pierre et Marie Curie, Paris Cedex 05 (France); Janicot, Serge [LOCEAN/IPSL, IRD, Universite Pierre et Marie Curie, Paris (France); Bader, Juergen [Bjerknes Centre for Climate Research, Bergen (Norway); Ruti, Paolo [Progetto Speciale Clima Globale, Ente Nazionale per le Nuove Tecnologie, l' Energia e l' Ambiente, Rome (Italy); Chauvin, Fabrice [GAME/CNRM, Meteo-France/CNRS, Toulouse (France)

    2011-11-15

    Rainfall over West Africa shows strong interannual variability related to changes in Sea Surface Temperature (SST). Nevertheless, this relationship seem to be non-stationary. A particular turning point is the decade of the 1970s, which witnessed a number of changes in the climatic system, including the climate shift of the late 1970s. The first aim of this study is to explore the change in the interannual variability of West African rainfall after this shift. The analysis indicates that the dipolar features of the rainfall variability over this region, related to changes in the Atlantic SST, disappear after this period. Also, the Pacific SST variability has a higher correlation with Guinean rainfall in the recent period. The results suggest that the current relationship between the Atlantic and Pacific El Nino phenomena is the principal responsible for these changes. A fundamental goal of climate research is the development of models simulating a realistic current climate. For this reason, the second aim of this work is to test the performance of Atmospheric General Circulation models in simulating rainfall variability over West Africa. The models have been run with observed SSTs for the common period 1957-1998 as part of an intercomparison exercise. The results show that the models are able to reproduce Guinean interannual variability, which is strongly related to SST variability in the Equatorial Atlantic. Nevertheless, problems in the simulation of the Sahelian interannual variability appear: not all models are able to reproduce the observed negative link between rainfall over the Sahel and El Nino-like anomalies in the Pacific, neither the positive correlation between Mediterranean SSTs and Sahelian rainfall. (orig.)

  2. BrO measurements over the Eastern North-Atlantic

    Directory of Open Access Journals (Sweden)

    U. Platt

    2009-12-01

    Full Text Available The aim of the work presented here was to detect BrO in the marine boundary layer over the Eastern North-Atlantic by Multi AXis-Differential Optical Absorption Spectroscopy (MAX-DOAS of scattered sunlight. With this technique, information about the concentration and the vertical profile of trace gases in the atmosphere can be gained. BrO can be formed in the marine atmosphere by degradation of biogenic organohalogens or by oxidation of bromide in sea salt aerosol. BrO influences the chemistry in marine air in many ways, e.g. since it catalytically destroys ozone, changes the NO2/NO-ratio as well as the OH/HO2-ratio and oxidises DMS. However, the abundance and the significance of BrO in the marine atmosphere is not yet fully understood.

    We report on data collected during a ship cruise, which took place along the West African Coast in February 2007, within the framework of the Surface Ocean PRocesses in the ANthropocene project (SOPRAN. Tropospheric BrO could be detected during this cruise at peak mixing ratios of (10.2±3.7 ppt at an assumed layer height of 1 km on 18 February 2007. Furthermore, it was found that the mean BrO concentrations increased when cruising close to the African Coast suggesting that at least part of the BrO might have originated from there.

  3. North Atlantic climate model bias influence on multiyear predictability

    Science.gov (United States)

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

    2018-01-01

    The influences of North Atlantic biases on multiyear predictability of unforced surface air temperature (SAT) variability are examined in the Kiel Climate Model (KCM). By employing a freshwater flux correction over the North Atlantic to the model, which strongly alleviates both North Atlantic sea surface salinity (SSS) and sea surface temperature (SST) biases, the freshwater flux-corrected integration depicts significantly enhanced multiyear SAT predictability in the North Atlantic sector in comparison to the uncorrected one. The enhanced SAT predictability in the corrected integration is due to a stronger and more variable Atlantic Meridional Overturning Circulation (AMOC) and its enhanced influence on North Atlantic SST. Results obtained from preindustrial control integrations of models participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5) support the findings obtained from the KCM: models with large North Atlantic biases tend to have a weak AMOC influence on SAT and exhibit a smaller SAT predictability over the North Atlantic sector.

  4. 77 FR 31330 - South Atlantic Fishery Management Council; Public Meetings

    Science.gov (United States)

    2012-05-25

    ... National Oceanic and Atmospheric Administration RIN 0648-XC042 South Atlantic Fishery Management Council; Public Meetings AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce. ACTION: Notice of public meetings. SUMMARY: The South Atlantic Fishery...

  5. Carotenoid dynamics in Atlantic salmon

    Directory of Open Access Journals (Sweden)

    Omholt Stig W

    2006-04-01

    Full Text Available Abstract Background Carotenoids are pigment molecules produced mainly in plants and heavily exploited by a wide range of organisms higher up in the food-chain. The fundamental processes regulating how carotenoids are absorbed and metabolized in vertebrates are still not fully understood. We try to further this understanding here by presenting a dynamic ODE (ordinary differential equation model to describe and analyse the uptake, deposition, and utilization of a carotenoid at the whole-organism level. The model focuses on the pigment astaxanthin in Atlantic salmon because of the commercial importance of understanding carotenoid dynamics in this species, and because deposition of carotenoids in the flesh is likely to play an important life history role in anadromous salmonids. Results The model is capable of mimicking feed experiments analyzing astaxanthin uptake and retention over short and long time periods (hours, days and years under various conditions. A sensitivity analysis of the model provides information on where to look for possible genetic determinants underlying the observed phenotypic variation in muscle carotenoid retention. Finally, the model framework is used to predict that a specific regulatory system controlling the release of astaxanthin from the muscle is not likely to exist, and that the release of the pigment into the blood is instead caused by the androgen-initiated autolytic degradation of the muscle in the sexually mature salmon. Conclusion The results show that a dynamic model describing a complex trait can be instrumental in the early stages of a project trying to uncover underlying determinants. The model provides a heuristic basis for an experimental research programme, as well as defining a scaffold for modelling carotenoid dynamics in mammalian systems.

  6. Numerical Simulations of Columbus’ Atlantic Crossings

    Science.gov (United States)

    1992-02-01

    Westerly Historical Magnetic Variation in the West Indies Virtually all early maps -’f the West Indies show the islands plotted several degrees north of...c1530) published for the first time by the Museo Naval, Madrid, 1983. Chaves’s formula for reaching the Leeward Islands is given in Lib. IV, Cap. i

  7. Seasonal variation in organotins in the waters of the Dona Paula Bay, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Meena, R.M.; Garg, A.; Jadhav, S.

    , Brancato MS, (2000) The TBT ban: out of the frying pan into the fire? Mar Pollut Bull 40:204–211 Gomez-Ariza JL, Santos MM, Morales E, Giraldes I, Samchez-Rodas D, Vieira N (2006) Organotin contamination in the Atlantic Ocean off the Iberian Penisula.... 2008 5 Portugal Coast 3-30 Dıez et al. 2005 6 Greece 2-70 Thomaidis et al. 2007 7 Japane coast 3.9-27* Murai et al. 2005 8 France 0.9-280* Michel & Averty 1999 9 west coast of Spain 0.9-196 Alez et al. 2006 * TBT values in ng l...

  8. 78 FR 76107 - Fisheries of the South Atlantic and the Gulf of Mexico; South Atlantic Fishery Management Council...

    Science.gov (United States)

    2013-12-16

    ... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration Fisheries of the South Atlantic and the Gulf of Mexico; South Atlantic Fishery Management Council (SAFMC) and Gulf of Mexico Fishery Management Council (GMFMC); Public Meeting AGENCY: National Marine Fisheries Service (NMFS...

  9. 50 CFR 600.520 - Northwest Atlantic Ocean fishery.

    Science.gov (United States)

    2010-10-01

    ... Northwest Atlantic Ocean fishery. (a) Purpose. Sections 600.520 and 600.525 regulate all foreign fishing... purposes of the Northwest Atlantic Ocean fishery, fishing areas are that portion of the EEZ shown inside... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Northwest Atlantic Ocean fishery. 600.520...

  10. Impact of interbasin exchange on the Atlantic overturning circulation

    NARCIS (Netherlands)

    Weijer, W.; Ruijter, W.P.M. de; Dijkstra, H.A.; Leeuwen, P.J. van

    2000-01-01

    The thermohaline exchange between the Atlantic and the Southern Ocean is analyzed, using a data set based on WOCE hydrographic data. It is shown that the salt and heat transports brought about by the South Atlantic subtropical gyre play an essential role in the Atlantic heat and salt budgets. It

  11. Turbidity, SOLAR RADIATION - ATMOSPHERIC and other data from MELVILLE, KNORR and other platforms in the NE Atlantic, NW Atlantic and South Atlantic Ocean from 1972-07-24 to 1989-01-13 (NODC Accession 9500080)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Eight data sets of Temperature, Depth, Salinity, dissolved Oxygen (CTD) data collected in South Atlantic Ocean, NE Atlantic (limit-40 W), NW Atlantic (limit-40 W)...

  12. Diet of Ctenogobius shufeldti (Jordan and Eigenmann, 1887 (Teleostei, Gobiidae in Guaratuba Bay, subtropical west Atlantic

    Directory of Open Access Journals (Sweden)

    Diego Zanlorenzi

    2011-02-01

    Full Text Available The diet composition of the American freshwater goby, Ctenogobius shufeldti, was investigated in an estuarine area and two of its tributaries. 397 individuals, total length from 21 to 70mm, were sampled over a period of 12 months and their stomach contents were analysed by the Frequency of Occurrence and Number of Points methods. According to the Alimentary Index, diet was constituted mainly by Ostracoda (IA=50.51 and Tanaidacea (IA=40.85, and secondarily by Gastropoda (IA=1.21, Amphipoda (IA=0.10, Isopoda (IA=0.01, Cirripedia (IA=0.01, Decapoda larvae (IA=0.01, Insecta (IA=0.01, Chlorophyta (IA=2.15 and Rodophyta (IA=0.15 filamentous algae, and plants (IA=4.99. Diversity of diet was higher in rivers than in the Bay. Except for Decapoda larvae, items found in the two rivers were the same. In the Bay, Amphipoda and Cirripedia were not found. Previous to this research, the filamentous algae Chlorophyta and Rodophyta had not been noted in the diet of this species in estuaries close to Guaratuba. In view of this, and regarding the possible roles played by cryptobenthic fish species in aquatic communities (Depczynski and Bellwood, 2003, it is concluded that C. shufeldti takes part in trophic dynamics feeding on benthic organisms as well as on algae, a behaviour that can result from both marine and continental influences existing in the region.

  13. Aluminium in an ocean general circulation model compared with the West Atlantic Geotraces cruises

    CSIR Research Space (South Africa)

    Van Hulten, M

    2013-10-01

    Full Text Available Hope Meeting Location: Liege, BELGIUM Date: MAY 02-06, 2011 Sponsor(s): Geotraces Program; Bonus; GoodHope JOURNAL OF MARINE SYSTEMS Volume: 126 Special Issue: SI Pages: 3-23 Published: OCT 2013 Abstract: A model of aluminium has been developed...

  14. Aluminium in an ocean general circulation model compared with the West Atlantic Geotraces cruises

    NARCIS (Netherlands)

    van Hulten, M. M. P.; Sterl, A.; Tagliabue, A.; Dutay, J. -C.; Gehlen, M.; de Baar, H. J. W.; Middag, R.

    2013-01-01

    A model of aluminium has been developed and implemented in an Ocean General Circulation Model (NEMO-PISCES). In the model, aluminium enters the ocean by means of dust deposition. The internal oceanic processes are described by advection, mixing and reversible scavenging. The model has been evaluated

  15. Relating petroleum system and play development to basin evolution: West African South Atlantic basins

    NARCIS (Netherlands)

    Beglinger, S.E.; Doust, H.; Cloetingh, S.A.P.L.

    2012-01-01

    Sedimentary basins can be classified according to their structural genesis and evolutionary history and the latter can be linked to petroleumsystem and playdevelopment. We propose an approach in which we use the established concepts in a new way: breaking basins down into their natural basin cycle

  16. Macro and trace elements in Paracentrotus lividus gonads from South West Atlantic areas

    DEFF Research Database (Denmark)

    Camacho, Carolina; Rocha, A. Cristina; Barbosa, Vera L.

    2018-01-01

    Sea urchin represents one of the most valuable seafood product being harvested and explored for their edible part, the gonads or roe. This species is generally considered a sentinel organism for ecotoxicological studies being widely used in monitoring programs to assess coastal aquatic environments...

  17. Politeness: West and East

    Directory of Open Access Journals (Sweden)

    - Джеффри Лич

    2014-12-01

    Full Text Available The present paper was planned for this issue of our journal, which Geoffrey Leech and I intended to devote to Politeness phenomena across cultures. It is based on his article titled “Politeness: Is there an East-West Divide?” (2005 which he suggested as a theoretical framework and includes results of our discussions held during our personal meetings and our epistolary exchange. Unfortunately the final version of the paper was never read by Geoffrey Leech for the reasons we all sadly know. Nevertheless I decided to publish it as a tribute to him in the knowledge that the result was not going to have the degree of excellence it would have had if he were still with us today. I therefore apologise for any mistakes or misinterpretations of his thoughts that might be found in the paper. The aim of this article is to sum up the main ideas of Politeness Theory presented earlier in Leech 1983, 2003, 2005, and other publications and discuss how that theory applies (or fails to apply to other languages, with the main emphasis on the Russian language and culture. The term ‘maxim’ used in Principles of Pragmatics (Leech 1983 is avoided here as much as possible, as it implies some kind of moral imperative, rather than a pragmatic constraint. Instead, a single constraint, which comprehends all the maxims (the Maxims of Tact, Generosity, Approbation, Modesty, Agreement, Sympathy, and is called the Grand Strategy of Politeness (GSP, is used. The GSP says: In order to be polite, S expresses or implies meanings which place a high value on what pertains to O- his/her wants, qualities, obligation, opinion, feelings (O = other person[s], [mainly the addressee, i.e. H = hearer] or place a low value on what pertains to S (S = self, speaker. The essential point is that these are not separate, independent constraints or maxims: they are instances of the operation of the GSP as ‘super-maxim’ which is an overarching framework for studying linguistic politeness

  18. Tsunami Warning Services for the U.S. and Canadian Atlantic Coasts

    Science.gov (United States)

    Whitmore, P. M.; Knight, W.

    2008-12-01

    In January 2005, the National Oceanic and Atmospheric Administration (NOAA) developed a tsunami warning program for the U.S. Atlantic and Gulf of Mexico coasts. Within a year, this program extended further to the Atlantic coast of Canada and the Caribbean Sea. Warning services are provided to U.S. and Canadian coasts (including Puerto Rico and the Virgin Islands) by the NOAA/West Coast and Alaska Tsunami Warning Center (WCATWC) while the NOAA/Pacific Tsunami Warning Center (PTWC) provides services for non-U.S. entities in the Caribbean Basin. The Puerto Rico Seismic Network (PRSN) is also an active partner in the Caribbean Basin warning system. While the nature of the tsunami threat in the Atlantic Basin is different than in the Pacific, the warning system philosophy is similar. That is, initial messages are based strictly on seismic data so that information is provided to those at greatest risk as fast as possible while supplementary messages are refined with sea level observations and forecasts when possible. The Tsunami Warning Centers (TWCs) acquire regional seismic data through many agencies, such as the United States Geological Survey, Earthquakes Canada, regional seismic networks, and the PRSN. Seismic data quantity and quality are generally sufficient throughout most of the Atlantic area-of-responsibility to issue initial information within five minutes of origin time. Sea level data are mainly provided by the NOAA/National Ocean Service. Coastal tide gage coverage is generally denser along the Atlantic coast than in the Pacific. Seven deep ocean pressure sensors (DARTs), operated by the National Weather Service (NWS) National Data Buoy Center, are located in the Atlantic Basin (5 in the Atlantic Ocean, 1 in the Caribbean, and 1 in the Gulf of Mexico). The DARTs provide TWCs with the means to verify tsunami generation in the Atlantic and provide critical data with which to calibrate forecast models. Tsunami warning response criteria in the Atlantic Basin

  19. An assessment of leaf-litter and epigaeic ants (Hymenoptera: Formicidae living in different landscapes of the Atlantic Forest Biome in the State of Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Roberta de Jesus Santos

    2017-11-01

    Full Text Available The Brazilian Atlantic Forest has a rich biodiversity increasingly threatened by human activities. Since the colonial period, the coast of the state of Bahia is among the most affected regions of Brazil by anthropic pressure. Bahia encloses Atlantic Forest remnants distributed in an area reaching 100-200 km along the east-west axis, by 1,000 km along the north-south axis, parallel to the coast of the Atlantic Ocean. We report hereafter the results of an intensive field survey of leaf litter and epigaeic ants realized in forest remnants of the Atlantic Forest landscapes within the original extension of the biome in 11 localities distributed along four degrees of latitude in the state of Bahia. In each site, 16 plots were collected using pitfall and eight using Winkler traps. We identified 391 ant species belonging to 71 genera and nine subfamilies. Among all species recorded, 21 were common to the whole 11 localities, while 98 species were recorded in a single locality. This study highlights the richness and diversity of epigaeic and leaf-litter ants living in the northern part of the Brazilian Atlantic Forest, and is one of the most representative soil ants’ inventories ever done in this biome for a single state of Brazil.

  20. 75 FR 35767 - Fisheries of the South Atlantic; South Atlantic Fishery Management Council; Public Meeting

    Science.gov (United States)

    2010-06-23

    ... (SERMA) in the South Atlantic, and receive updates on state enforcement efforts of 2010 snapper grouper... ] Conservation Biology Institute (MCBI) which addresses the challenges of enforcing regulations within the vast...

  1. 76 FR 62331 - Atlantic Highly Migratory Species; Atlantic Shark Management Measures

    Science.gov (United States)

    2011-10-07

    ... Species; Atlantic Shark Management Measures AGENCY: National Marine Fisheries Service (NMFS), National... blacknose sharks, NMFS is declaring the following stock status determinations. Sandbar sharks are still overfished, but no longer experiencing overfishing. Dusky sharks are still overfished and still experiencing...

  2. 76 FR 56120 - Atlantic Highly Migratory Species; North and South Atlantic Swordfish Quotas

    Science.gov (United States)

    2011-09-12

    ... recreational fishing for swordfish in the Atlantic Ocean, including the Caribbean Sea and Gulf of Mexico, by... http://www.iccat.int/en/ . One swordfish measure adopted at the 2010 meeting, and one swordfish measure...

  3. Persistent influence of tropical North Atlantic wintertime sea surface temperature on the subsequent Atlantic hurricane season

    Science.gov (United States)

    Wang, Xidong; Liu, Hailong; Foltz, Gregory R.

    2017-08-01

    This study explores the seasonally lagged impact of wintertime sea surface temperature (SST) in the Atlantic main development region (MDR) on the subsequent Atlantic hurricane season. It is found that wintertime SST anomalies in the MDR can persist into the summer, explaining 42% of the variance in the subsequent hurricane season's SST during 1951-2010. An anomalously warm wintertime in the MDR is usually followed by an anomalously active hurricane season. Analysis shows an important constraint on the seasonal evolution of the MDR SST by the water vapor feedback process, in addition to the well-known wind-evaporation-SST and cloud-SST feedback mechanisms over the tropical North Atlantic. The water vapor feedback influences the seasonal evolution of MDR SST by modulating seasonal variations of downward longwave radiation. This wintertime thermal control of hurricane activity has significant implications for seasonal predictions and long-term projections of hurricane activity over the North Atlantic.

  4. 77 FR 64317 - Fisheries of the South Atlantic; South Atlantic Fishery Management Council; Public Meeting

    Science.gov (United States)

    2012-10-19

    ... Crowne Plaza Hotel, 4831 Tanger Outlet Blvd., North Charleston, SC 29418; telephone: (843) 744- 4422; fax... the Gulf of Mexico Fishery Management Council to the South Atlantic Fishery Management Council and...

  5. 76 FR 14378 - Fisheries of the South Atlantic; South Atlantic Fishery Management Council; Public Meeting

    Science.gov (United States)

    2011-03-16

    ..., 4831 Tanger Outlet Blvd., North Charleston, SC 29418; telephone: (866) 358- 6255. Council address... Migratory Pelagics Fishery Management Plan (FMP) for the South Atlantic and Gulf of Mexico addressing Annual...

  6. Enhanced δ13C and δ18O Differences Between the South Atlantic and South Pacific During the Last Glaciation: The Deep Gateway Hypothesis

    Science.gov (United States)

    Sikes, Elisabeth L.; Allen, Katherine A.; Lund, David C.

    2017-10-01

    Enhanced vertical gradients in benthic foraminiferal δ13C and δ18O in the Atlantic and Pacific during the last glaciation have revealed that ocean overturning circulation was characterized by shoaling of North Atlantic sourced interior waters; nonetheless, our understanding of the specific mechanisms driving these glacial isotope patterns remains incomplete. Here we compare high-resolution depth transects of Cibicidoides spp. δ13C and δ18O from the Southwest Pacific and the Southwest Atlantic to examine relative changes in northern and southern sourced deep waters during the Last Glacial Maximum (LGM) and deglaciation. During the LGM, our transects show that water mass properties and boundaries in the South Atlantic and Pacific were different from one another. The Atlantic between 1.0 and 2.5 km was more than 1‰ enriched in δ13C relative to the Pacific and remained more enriched through the deglaciation. During the LGM, Atlantic δ18O was 0.5‰ more enriched than the Pacific, particularly below 2.5 km. This compositional difference between the deep portions of the basins implies independent deep water sources during the glaciation. We attribute these changes to a "deep gateway" effect whereby northern sourced waters shallower than the Drake Passage sill were unable to flow southward into the Southern Ocean because a net meridional geostrophic transport cannot be supported in the absence of a net east-west circumpolar pressure gradient above the sill depth. We surmise that through the LGM and early deglaciation, shoaled northern sourced waters were unable to escape the Atlantic and contribute to deep water formation in the Southern Ocean.

  7. A ground temperature map of the North Atlantic permafrost region based on remote sensing and reanalysis data

    DEFF Research Database (Denmark)

    Westermann, S.; Østby, T. I.; Gisnås, K.

    2015-01-01

    input parameters which for each grid cell allows scanning the range of possible results by running many realizations with different parameters. The approach is applied to the unglacierized land areas in the North Atlantic region, an area of more than 5 million km2 ranging from the Ural Mountains...... in the east to the Canadian Archipelago in the west. A comparison to in situ temperature measurements in 143 boreholes suggests a model accuracy better than 2.5 °C, with 139 considered boreholes within this margin. The statistical approach with a large number of realizations facilitates estimating...

  8. Levels and patterns of persistent organochlorines in minke whale (Balaenoptera acutorostrata) stocks from the North Atlantic and European Arctic

    Energy Technology Data Exchange (ETDEWEB)

    Hobbs, K.E.; Muir, D.C.G.; Born, E.W.; Dietz, R.; Haug, T.; Metcalfe, T.; Metcalfe, C.; Oien, N

    2003-02-01

    Minke whales appear to be quite mobile and have multiple feeding areas in the NE Atlantic Ocean. - Regional variation in PCBs and organochlorine (OC) pesticide concentrations was examined using the blubber of 155 minke whales (Balaenoptera acutorostrata) sampled in seven regions in the North Atlantic and European Arctic, including western and southeastern Greenland, the Norwegian Sea, the North Sea and the Barents Sea. The levels and relative proportions of OCs were also used to examine the boundaries for North Atlantic minke whale stocks previously defined by the International Whaling Commission (IWC). Concentrations of major OC groups ({sigma}PCB, 89.1-22 800 ng/g lipid; {sigma}DDT, 65.3-6280 ng/g lipid; {sigma}CHL, 33.3-2110 ng/g lipid) generally increased from west to east, while HCH concentrations ({sigma}HCH, <1-497 ng/g lipid) showed the opposite trend. Statistical comparison between six regions using sex-adjusted least squared mean concentrations showed that minke whales from the Barents Sea had significantly higher concentrations of {sigma}PCBs than those from the Vestfjorden/Lofoten, the North Sea, and west Svalbard, as well as significantly higher {sigma}DDT concentrations compared to west Greenland animals. The differences in concentrations suggest that west and southeast Greenland minkes may represent one group of whales, which are distinct from both the Jan Mayen minkes and those from other IWC defined stocks in northern European waters. Principal components analysis using proportions of 71 PCB congeners and 20 OC pesticides (of total OCs) did not reveal any major differences among groups although minkes from the North Sea were distinguished from those from Greenland waters by higher loadings of more highly chlorinated PCBs and recalcitrant OC pesticides. The general similarity in mean levels of {sigma}PCBs, {sigma}DDT and {sigma}CHL, as well as mean principal components analysis scores, among minkes sampled at Jan Mayen, Svalbard, Vestfjorden

  9. North Atlantic ocean circulation during the Last Glacial Maximum: a combined modelling and magnetic sediment proxy study

    Science.gov (United States)

    Watkins, S. J.; Maher, B. A.; Bigg, G. R.

    2003-04-01

    An increasing number of ocean modelling and palaeo-data studies has provided evidence that the thermohaline circulation may have existed in the past in a different configuration to the present-day. Here, we use a twin approach, combining ocean model results and sediment proxy data, to investigate N. Atlantic circulation at the Last Glacial Maximum (LGM). Ocean model experiments at UEA (Norwich) indicate the existence of three possible stable ocean circulation states during the LGM. Two states have formation of intermediate/deep water in the North Atlantic (with different formation sites, rates and sinking depths), the third state has all deep water formation in the Southern Ocean. Forcing fields from these circulation states are used to provide input fields for an iceberg trajectory model, which is then used to investigate the effect of these different surface circulation patterns on iceberg drift. Magnetic measurements of deep-sea sediments have been used to identify ice-rafted detritus (IRD), allowing reconstruction of LGM iceberg trajectories. Magnetic measurements have the benefit of being relatively rapid and also non-destructive. The magnetic properties of > 130 deep-sea LGM sediment samples, from across the North Atlantic, have been measured, together with samples from potential source areas. Fuzzy c-means cluster analysis of selected, diagnostic magnetic parameters was used to characterise the sediment and identify the main controls on sedimentation. The clustering distinguishes lower-latitude, aeolian input west of Africa from other detrital sediment inputs to the north and west North Atlantic. The magnetic properties of sediments along the eastern coast of Greenland, and in the Labrador Sea and central Atlantic, indicate the presence of IRD rich in low-coercivity, coarse-grained magnetite. IRD in sediments east of the Gulf of St. Lawrence is characterised by the presence of both haematite and coarse-grained magnetite. Of the three modelled ocean states

  10. 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...

  11. Coccolithophores in the equatorial Atlantic Ocean

    DEFF Research Database (Denmark)

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

    2000-01-01

    tenuis are strongly diminished, causing an increase in relative abundance of the lower photic zone taxa Florisphaera profunda and Gladiolithus flabellatus. During the past 140,000 years the surface water circulation of the equatorial Atlantic has changed drastically, as can be seen from changes...

  12. Atlantic hurricane activity during the last millennium

    Science.gov (United States)

    Burn, Michael J.; Palmer, Suzanne E.

    2015-01-01

    Hurricanes are a persistent socio-economic hazard for countries situated in and around the Main Development Region (MDR) of Atlantic tropical cyclones. Climate-model simulations have attributed their interdecadal variability to changes in solar and volcanic activity, Saharan dust flux, anthropogenic greenhouse gas and aerosol emissions and heat transport within the global ocean conveyor belt. However, the attribution of hurricane activity to specific forcing factors is hampered by the short observational record of Atlantic storms. Here, we present the Extended Hurricane Activity (EHA) index, the first empirical reconstruction of Atlantic tropical cyclone activity for the last millennium, derived from a high-resolution lake sediment geochemical record from Jamaica. The EHA correlates significantly with decadal changes in tropical Atlantic sea surface temperatures (SSTs; r = 0.68; 1854–2008), the Accumulated Cyclone Energy index (ACE; r = 0.90; 1851–2010), and two annually-resolved coral-based SST reconstructions (1773–2008) from within the MDR. Our results corroborate evidence for the increasing trend of hurricane activity during the Industrial Era; however, we show that contemporary activity has not exceeded the range of natural climate variability exhibited during the last millennium. PMID:26243340

  13. Subpolar North Atlantic glider observations for OSNAP

    Science.gov (United States)

    Zhou, C.; Hodges, B.; Bower, A. S.; Yang, J.; Lin, X.

    2016-02-01

    OSNAP is an international program designed to provide a continuous record of the full-water-column, trans-basin fluxes of heat, mass, and freshwater in the subpolar North Atlantic. The observational efforts of this program are focused largely along lines connecting Labrador to Greenland, and Greenland to Scotland. The OSNAP experimental plan includes continuous sampling by Slocum G2 gliders along the latter (easternmost) of these two sections, specifically across the northeastward-flowing North Atlantic Current in the Iceland Basin. The glider observations, a collaboration between the Ocean University of China and Woods Hole Oceanographic Institution, provide higher spatial resolution of water properties than is possible from moorings alone. These observations commenced in June 2015 with a mission to fly back and forth along a section between two OSNAP moorings, profiling from the surface to 1000-m depth. As of September 2015, five sections (including over 240 profiles) have been recorded. As expected, the data indicates energetic intraseasonal variability at smaller scales than can be captured by the OSNAP mooring array. We are investigating how this variability may impact calculated fluxes of heat, mass, and freshwater. The glider repeatedly crossed a cyclonic eddy between the two moorings, enabling study of fine thermohaline structure during the development and dissipation of mesoscale eddies in the subpolar North Atlantic. With additional sensors measuring fluorescence, dissolved oxygen, nitrate, and multispectral light, the dataset also has the potential to significantly advance our understanding of the biogeochemical processes of mesoscale and submesoscale eddies in the subpolar North Atlantic.

  14. North Atlantic SST Patterns and NAO Flavors

    Science.gov (United States)

    Rousi, E.; Rahmstorf, S.; Coumou, D.

    2017-12-01

    North Atlantic SST variability results from the interaction of atmospheric and oceanic processes. The North Atlantic Oscillation (NAO) drives changes in SST patterns but is also driven by them on certain time-scales. These interactions are not very well understood and might be affected by anthropogenic climate change. Paleo reconstructions indicate a slowdown of the Atlantic Meridional Overturning Circulation (AMOC) in recent decades leading to a pronounced cold anomaly ("cold blob") in the North Atlantic (Rahmstorf et al., 2015). The latter may favor NAO to be in its negative mode. In this work, sea surface temperature (SST) patterns are studied in relation to NAO variations, with the aim of discovering preferred states and understanding their interactions. SST patterns are analyzed with Self-Organizing Maps (SOM), a clustering technique that helps identify different spatial patterns and their temporal evolution. NAO flavors refer to different longitudinal positions and tilts of the NAO action centers, also defined with SOMs. This way the limitations of the basic, index-based, NAO-definition are overcome, and the method handles different spatially shapes associated with NAO. Preliminary results show the existence of preferred combinations of SSTs and NAO flavors, which in turn affect weather and climate of Europe and North America. The possible influence of the cold blob on European weather is discussed.

  15. Atlantic hurricane activity during the last millennium

    Science.gov (United States)

    Burn, Michael J.; Palmer, Suzanne E.

    2015-08-01

    Hurricanes are a persistent socio-economic hazard for countries situated in and around the Main Development Region (MDR) of Atlantic tropical cyclones. Climate-model simulations have attributed their interdecadal variability to changes in solar and volcanic activity, Saharan dust flux, anthropogenic greenhouse gas and aerosol emissions and heat transport within the global ocean conveyor belt. However, the attribution of hurricane activity to specific forcing factors is hampered by the short observational record of Atlantic storms. Here, we present the Extended Hurricane Activity (EHA) index, the first empirical reconstruction of Atlantic tropical cyclone activity for the last millennium, derived from a high-resolution lake sediment geochemical record from Jamaica. The EHA correlates significantly with decadal changes in tropical Atlantic sea surface temperatures (SSTs; r = 0.68 1854-2008), the Accumulated Cyclone Energy index (ACE; r = 0.90 1851-2010), and two annually-resolved coral-based SST reconstructions (1773-2008) from within the MDR. Our results corroborate evidence for the increasing trend of hurricane activity during the Industrial Era; however, we show that contemporary activity has not exceeded the range of natural climate variability exhibited during the last millennium.

  16. 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...

  17. Atlantic hurricane activity during the last millennium.

    Science.gov (United States)

    Burn, Michael J; Palmer, Suzanne E

    2015-08-05

    Hurricanes are a persistent socio-economic hazard for countries situated in and around the Main Development Region (MDR) of Atlantic tropical cyclones. Climate-model simulations have attributed their interdecadal variability to changes in solar and volcanic activity, Saharan dust flux, anthropogenic greenhouse gas and aerosol emissions and heat transport within the global ocean conveyor belt. However, the attribution of hurricane activity to specific forcing factors is hampered by the short observational record of Atlantic storms. Here, we present the Extended Hurricane Activity (EHA) index, the first empirical reconstruction of Atlantic tropical cyclone activity for the last millennium, derived from a high-resolution lake sediment geochemical record from Jamaica. The EHA correlates significantly with decadal changes in tropical Atlantic sea surface temperatures (SSTs; r = 0.68; 1854-2008), the Accumulated Cyclone Energy index (ACE; r = 0.90; 1851-2010), and two annually-resolved coral-based SST reconstructions (1773-2008) from within the MDR. Our results corroborate evidence for the increasing trend of hurricane activity during the Industrial Era; however, we show that contemporary activity has not exceeded the range of natural climate variability exhibited during the last millennium.

  18. 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

  19. Potential links between the North Atlantic Oscillation and decreasing precipitation and runoff on Sardinia

    Science.gov (United States)

    Montaldo, Nicola; Sarigu, Alessio

    2017-04-01

    Recently, climate change and human activities increased the desertification process in the Mediterranean regions, with dramatic consequences for agriculture and water resources. On the Sardinia island (Italy), runoff decreased significantly in the 1975-2010 period with a mean yearly runoff reduction of more than 50% compared to the previous 1922-1974 period. The decrease in runoff severely impacts the management of water resources on the Sardinia island, resulting in water supply restrictions even for domestic consumption. In the 10 Sardinian basins, with a longer database (at least 40 complete years of data, including data from the past 10 years), the trend of yearly runoff computed with the Mann-Kendall test is negative, with the Mann-Kendall τ values ranging from -0.39 to -0.2. The reason for the decrease in runoff is mainly the alarming decrease in the winter precipitation over the past few decades everywhere on the Sardinia island. Indeed, most of the yearly runoff of the Sardinian basins (on average, 70%) is produced by the winter precipitation due to the typical seasonality of the Mediterranean rainfall regime. Surprisingly, the winter precipitation trend is not homogenous; the negative trend is higher on the Sardinian west coast and becomes lower as one crosses the island toward the east coast. At the rain stations on the east coast, the τ Mann-Kendall values of the winter precipitation become almost half of the τ Mann-Kendall values on the west coast, which is exposed to the western European climate dynamics. In this sense, winter precipitation is highly correlated with the North Atlantic Oscillation (NAO), which is a weather phenomenon in the North Atlantic Ocean that controls the direction and strength of westerly winds and storm tracks into Europe. High negative correlations (up to -0.45) between winter NAO and winter precipitation are estimated along the west coast. Meanwhile, the correlations decrease as one crosses the island toward the east

  20. West African Journal of Medicine

    African Journals Online (AJOL)

    the use of manual vacuum aspiration for uterine evacuation9. Uterine evacuation is one of the most commonly performed procedures in our center and procured abortion With its numerous complications. West African Journal of Medicine Vol. 26, N o. 4. Treatment Outcome of Asherman's Syndrome is a particular problem in ...

  1. Upgrading of the West Area

    CERN Multimedia

    1983-01-01

    The rejigged main hall (EHW1) in the West Area: on background, below the crane, is the brown yoke of the Omega magnet which had been resited. The upgrading was completed by the time in July when 400 GeV protons arrived. See Annual Report 1983 p. 107.

  2. WEST AFRICAN JOURNAL OF MEDICINE

    African Journals Online (AJOL)

    ABSTRACT. Goitre in the West African sub-region is caused by iodine deficiency and goitrogens in the diet. Supplementary iodine nutrition on a mass scale was started in Ghana in 1996. In areas where iodine deficiency have been corrected the histological pattern of goitre changes and this influences surgical decision.

  3. West African Journal of Medicine

    African Journals Online (AJOL)

    _ WEST AFRICAN JOURNAL OF MEDICINE. CLINI CAL PRA CTI CE. Pain Management inAdult Acute Sickle Cell Pain Crisis: A Viewpoint. Chagriner la direction dans la crise de douleur de cellule de faucille adulte: un point de Vue . E. Udezue*, E. HerreraT. ABSTRACT. BACKGROUND: The acute pain crisis of sickle cell ...

  4. West Nile Virus Neuroinvasive Disease

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2009-07-01

    Full Text Available Epidemiological features of West Nile Virus (WNV disease among children (<18 years of age reported to the Centers for Disease Control and Prevention from 1999 through 2007 were analyzed and compared with those of adult WNV neuroinvasive disease (WNND, in a study at CDC&P, Fort Collins, CO.

  5. WEST AFRICAN JOURNAL OF MEDICINE

    African Journals Online (AJOL)

    Administrator

    Duvie SOA, Endeley EML, Danniya. MH. Urolithiasis in Maiduguri: The. Nigerian Savannah belt Experience. West. Afri Med. 1988; 7: 148–61. 10. Hassan I, Mohammed I. Urethral calculi: a review. East Afr Med J. 1993;. 70: 523–5. 11. Ahmed A, Saeed NM. Experience with the management of urethral stones presenting with ...

  6. Verbal aspects in West Greenlandic

    DEFF Research Database (Denmark)

    Trondhjem, Naja Blytmann

    2017-01-01

    In this article, lexical aspectual types in West Greenlandic are investigated in the five aspectual types, states, achievements, semelfactives, activities and accomplishments. It is shown that derivational verbalizing affixes include aspectual type congruent with the lexical aspect and how the as...

  7. The West in Early Cinema

    NARCIS (Netherlands)

    Verhoeff, Nanna

    2006-01-01

    Verhoeff investigates the emergence of the western genre, made in the first two decades of cinema (1895-1915). By analyzing many unknown and forgotten films from international archives she traces the relationships between films about the American West, their surrounding films, and other popular

  8. Primary Schooling in West Bengal

    Science.gov (United States)

    Sen, Amartya

    2010-01-01

    With his Nobel Prize award money, Amartya Sen set up the Pratichi Trust which carries out research, advocacy and experimental projects in basic education, primary health care, and women's development in West Bengal and Bangladesh. Professor Sen himself took active interest in this work--helping set the agenda, looking at the evidence from…

  9. The myth of the West

    Directory of Open Access Journals (Sweden)

    Onelio Olivera Blanco

    2005-12-01

    Full Text Available The next job leads to some reflections on one of the oldest myths of humanity: the myth of the cultural superiority of what bourgeois historiography called the West as opposed to the alleged low level of development than the same conception calls East. Illustrative examples the fallacy of this view is shown.

  10. WEST AFRICAN JOURNAL OF MEDICINE

    African Journals Online (AJOL)

    user1

    Kaushik B, Samiran B. Prevalence of underweight and stunting among school children in West Bengal. Indian J. Pediatr. 2008; 75: 1272. 16. Jafar TH, Qadri Z, Islam M, Hatcher J,. Bhutta ZA, Chaturvedi N. Rise in childhood obesity with persistently high rates of undernutrition among urban school-aged Indo-Asian children.

  11. Librarianship in Francophone West Africa.

    Science.gov (United States)

    Aguolu, C. C.

    1982-01-01

    Discusses the current level of library development and librarianship in francophone West Africa, taking Senegal as a case in point. The topics addressed include the impact of colonialism on library development, the structure of library services, the role of UNESCO seminars in library development, and the education of library personnel. (JL)

  12. WEST AFRICAN JOURNAL OF MEDICINE

    African Journals Online (AJOL)

    user1

    West African Journal of Medicine Vol. 30, No. 2 March–April, 2011. INTRODUCTION. Alternating hemiplegia of childhood. (AHC) is a rare neurological disorder that goes undiagnosed in many cases. It has a prevalence of about one case per million.1 It was first described by Vernot and Steele in 1971.2 Within this diagnosis.

  13. WEST AFRICAN JOURNAL OF MEDICINE

    African Journals Online (AJOL)

    user1

    West African Journal of Medicine Vol. 30, No. 2 March–April, 2011. A. E. Fawibe and Associates. Unilateral Tuberculous Lung Destruction. INTRODUCTION. Unilateral lung destruction is a .... occasional low grade fever associated with weight loss despite good .... right ventricular diastolic dysfunction and moderate tricuspid ...

  14. The future of transit in West Virginia.

    Science.gov (United States)

    2013-12-01

    The Future of Transit in West Virginia is a study of the current system of public transportation in West Virginia and : an examination of issues, priorities and projections of the public transportation network in the coming years. The : purpose...

  15. West Indian Prose Fiction in the Sixties

    Science.gov (United States)

    Brathwaite, Edward

    1971-01-01

    A Review and critical discussion of the West Indian prose fiction in the sixties by one of the best-known poets of the Carribean and a member of the faculty of the University of West Indies, Jamaica. (JM)

  16. Team West Virginia/Rome Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Korakakis, Dimitris [West Virginia Univ., Morgantown, WV (United States)

    2017-04-10

    Overall, the team, West Virginia University (WVU) and University of Rome Tor Vergata (UTV), has a goal of building an attractive, low-cost, energy-efficient solar-powered home that represents both the West Virginian and Italian cultures.

  17. Multivariate forecasting of total water storage anomalies over West Africa from multi-satellite data

    Science.gov (United States)

    Kusche, Jürgen; Forootan, Ehsan; Krasbutter, Ina; Schuh, Wolf-Dieter; Eicker, Annette; Diekkrüger, Bernd; Schmidt, Michael; Shum, Ck

    2013-04-01

    For West Africa, large-scale weather-related extreme hydrological conditions such as droughts or floods may persist over several months and usually have devastating environmental, social and economic impacts. Assessing and forecasting these conditions is therefore an important activity, in which data from the Gravity Recovery and Climate Experiment (GRACE) mission has been shown to be very useful. In this study, we describe a new statistical, data-driven approach to predict total water storage anomalies over West Africa from gravity data obtained from of GRACE, rainfall data from the Tropical Rainfall Measuring Mission (TRMM), and sea surface temperature data products over the Atlantic, Pacific and Indian oceans. Major teleconnections within these data sets were identified by independent component analysis, and linked via low-degree autoregressive models to build a predictive framework for forecasting total water storage, a quantity which is hard to observe in the field but important for agricultural and water resource management. After a learning phase of 80 months, our approach predicts water storage from rainfall and sea surface temperature data alone that fits to observed GRACE data at 79% after one year and 62% after two years. This means, our approach should be able to bridge the present GRACE data gaps of one month about each 162 days as well as a - hopefully - limited gap between GRACE and the GRACE-FO mission for West Africa. Keywords: Forecasting GRACE-TWS, West-Africa, ICA; AR model

  18. Onset of deglacial warming in West Antarctica driven by local orbital forcing

    Science.gov (United States)

    WAIS Divide Project Members,; Fudge, T. J.; Steig, Eric J.; Markle, Bradley R.; Schoenemann, Spruce W.; Ding, Qinghua; Taylor, Kendrick C.; McConnell, Joseph R.; Brook, Edward J.; Sowers, Todd; White, James W. C.; Alley, Richard B.; Cheng, Hai; Clow, Gary D.; Cole-Dai, Jihong; Conway, Howard; Cuffey, Kurt M.; Edwards, Jon S.; Edwards, R. Lawrence; Edwards, Ross; Fegyveresi, John M.; Ferris, David; Fitzpatrick, Joan J.; Johnson, Jay; Hargreaves, Geoffrey; Lee, James E.; Maselli, Olivia J.; Mason, William; McGwire, Kenneth C.; Mitchell, Logan E.; Mortensen, Nicolai B.; Neff, Peter; Orsi, Anais J.; Popp, Trevor J.; Schauer, Andrew J.; Severinghaus, Jeffrey P.; Sigl, Michael; Spencer, Matthew K.; Vaughn, Bruce H.; Voigt, Donald E.; Waddington, Edwin D.; Wang, Xianfeng; Wong, Gifford J.

    2013-01-01

    The cause of warming in the Southern Hemisphere during the most recent deglaciation remains a matter of debate. Hypotheses for a Northern Hemisphere trigger, through oceanic redistributions of heat, are based in part on the abrupt onset of warming seen in East Antarctic ice cores and dated to 18,000 years ago, which is several thousand years after high-latitude Northern Hemisphere summer insolation intensity began increasing from its minimum, approximately 24,000 years ago. An alternative explanation is that local solar insolation changes cause the Southern Hemisphere to warm independently. Here we present results from a new, annually resolved ice-core record from West Antarctica that reconciles these two views. The records show that 18,000 years ago snow accumulation in West Antarctica began increasing, coincident with increasing carbon dioxide concentrations, warming in East Antarctica and cooling in the Northern Hemisphere associated with an abrupt decrease in Atlantic meridional overturning circulation. However, significant warming in West Antarctica began at least 2,000 years earlier. Circum-Antarctic sea-ice decline, driven by increasing local insolation, is the likely cause of this warming. The marine-influenced West Antarctic records suggest a more active role for the Southern Ocean in the onset of deglaciation than is inferred from ice cores in the East Antarctic interior, which are largely isolated from sea-ice changes.

  19. 75 FR 17463 - Key West Bank, Key West, Florida; Notice of Appointment of Receiver

    Science.gov (United States)

    2010-04-06

    ... DEPARTMENT OF THE TREASURY Office of Thrift Supervision Key West Bank, Key West, Florida; Notice of Appointment of Receiver Notice is hereby given that, pursuant to the authority contained in... Federal Deposit Insurance Corporation as sole Receiver for Key West Bank, Key West, Florida, (OTS No...

  20. 33 CFR 110.189a - Key West Harbor, Key West, Fla., naval explosives anchorage area.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Key West Harbor, Key West, Fla..., DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Anchorage Grounds § 110.189a Key West Harbor, Key West, Fla., naval explosives anchorage area. (a) The anchorage ground. A circular area with its...

  1. West African Journal of Radiology: Editorial Policies

    African Journals Online (AJOL)

    Focus and Scope. The West African Journal of Radiology is the official publication of Association of Radiologists of West Africa. The Association was formed in the year 1963 while the Journal of West African Radiology was officially lunched in 1982. Membership consists of diagnostic, therapy radiologists, interventional ...

  2. 40 CFR 81.349 - West Virginia.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false West Virginia. 81.349 Section 81.349... Virginia. West Virginia—TSP Designated area Does not meet primary standards Does not meet secondary... district in Berkeley County X Remainder of State X West Virginia—SO2 Designated area Does not meet primary...

  3. Population Structure of West Greenland Narwhals

    DEFF Research Database (Denmark)

    Riget, F.; Dietz, R.; Møller, P.

    The hypothesis that different populations of narwhals in the West Greenland area exist has been tested by different biomarkers (metal and organochlorine concentrations, stable isotopes and DNA). Samples of muscle, liver, kidney, blubber and skin tissues of narwhals from West Greenland have been...... isotopes could not support the population structure with two West Greenland populations suggested by the genetic study....

  4. Northward advection of Atlantic water in the eastern Nordic Seas over the last 3000 yr

    Directory of Open Access Journals (Sweden)

    C. V. Dylmer

    2013-07-01

    Full Text Available Three marine sediment cores distributed along the Norwegian (MD95-2011, Barents Sea (JM09-KA11-GC, and Svalbard (HH11-134-BC continental margins have been investigated in order to reconstruct changes in the poleward flow of Atlantic waters (AW and in the nature of upper surface water masses within the eastern Nordic Seas over the last 3000 yr. These reconstructions are based on a limited set of coccolith proxies: the abundance ratio between Emiliania huxleyi and Coccolithus pelagicus, an index of Atlantic vs. Polar/Arctic surface water masses; and Gephyrocapsa muellerae, a drifted coccolith species from the temperate North Atlantic, whose abundance changes are related to variations in the strength of the North Atlantic Current. The entire investigated area, from 66 to 77° N, was affected by an overall increase in AW flow from 3000 cal yr BP (before present to the present. The long-term modulation of westerlies' strength and location, which are essentially driven by the dominant mode of the North Atlantic Oscillation (NAO, is thought to explain the observed dynamics of poleward AW flow. The same mechanism also reconciles the recorded opposite zonal shifts in the location of the Arctic front between the area off western Norway and the western Barents Sea–eastern Fram Strait region. The Little Ice Age (LIA was governed by deteriorating conditions, with Arctic/Polar waters dominating in the surface off western Svalbard and western Barents Sea, possibly associated with both severe sea ice conditions and a strongly reduced AW strength. A sudden short pulse of resumed high WSC (West Spitsbergen Current flow interrupted this cold spell in eastern Fram Strait from 330 to 410 cal yr BP. Our dataset not only confirms the high amplitude warming of surface waters at the turn of the 19th century off western Svalbard, it also shows that such a warming was primarily induced by an excess flow of AW which stands as unprecedented over the last 3000 yr.

  5. Habitat suitability of the Atlantic bluefin tuna by size class: An ecological niche approach

    Science.gov (United States)

    Druon, Jean-Noël; Fromentin, Jean-Marc; Hanke, Alex R.; Arrizabalaga, Haritz; Damalas, Dimitrios; Tičina, Vjekoslav; Quílez-Badia, Gemma; Ramirez, Karina; Arregui, Igor; Tserpes, George; Reglero, Patricia; Deflorio, Michele; Oray, Isik; Saadet Karakulak, F.; Megalofonou, Persefoni; Ceyhan, Tevfik; Grubišić, Leon; MacKenzie, Brian R.; Lamkin, John; Afonso, Pedro; Addis, Piero

    2016-03-01

    An ecological niche modelling (ENM) approach was used to predict the potential feeding and spawning habitats of small (5-25 kg, only feeding) and large (>25 kg) Atlantic bluefin tuna (ABFT), Thunnus thynnus, in the Mediterranean Sea, the North Atlantic and the Gulf of Mexico. The ENM was built bridging knowledge on ecological traits of ABFT (e.g. temperature tolerance, mobility, feeding and spawning strategy) with patterns of selected environmental variables (chlorophyll-a fronts and concentration, sea surface current and temperature, sea surface height anomaly) that were identified using an extensive set of precisely geo-located presence data. The results highlight a wider temperature tolerance for larger fish allowing them to feed in the northern - high chlorophyll levels - latitudes up to the Norwegian Sea in the eastern Atlantic and to the Gulf of Saint Lawrence in the western basin. Permanent suitable feeding habitat for small ABFT was predicted to be mostly located in temperate latitudes in the North Atlantic and in the Mediterranean Sea, as well as in subtropical waters off north-west Africa, while summer potential habitat in the Gulf of Mexico was found to be unsuitable for both small and large ABFTs. Potential spawning grounds were found to occur in the Gulf of Mexico from March-April in the south-east to April-May in the north, while favourable conditions evolve in the Mediterranean Sea from mid-May in the eastern to mid-July in the western basin. Other secondary potential spawning grounds not supported by observations were predicted in the Azores area and off Morocco to Senegal during July and August when extrapolating the model settings from the Gulf of Mexico into the North Atlantic. The presence of large ABFT off Florida and the Bahamas in spring was not explained by the model as is, however the environmental variables other than the sea surface height anomaly appeared to be favourable for spawning in part of this area. Defining key spatial and

  6. Gravity-driven structures and rift basin evolution: Rio Muni Basin, offshore equatorial West Africa

    Energy Technology Data Exchange (ETDEWEB)

    Turner, J.P. [Univ. of Birmingham (United Kingdom)

    1995-08-01

    Offshore Equatorial Guinea, west Africa, gravity-driven nappes, more than 1 km thick and 15 km from head to toe, provide key evidence in reconstructing the late synrift: evolution of this part of the South Atlantic margin basin system. Furthermore, Aptian-Cenomanian carbonate and clastic rocks in the nappes` allochthonous hanging walls are attracting interest as a new exploration play in west Africa. The nappes exhibit a range of geometries that suggest they share many of the same deformation processes as thin-skin thrust and linked extensional fault systems. Not only are these structures significant in their own right, representing a rare example of gravity tectonics in the virtual absence of major halokinesis, but their presence may record an other-wise undetectable process active during the transition from a rift basin to a passive continental margin. A review of Equatorial Guinea in its pre-Atlantic configuration, alongside neighboring basins in Brazil (the Sergipe-Alagoas basin) and Gabon, suggests that gravity gliding was sustained by a relatively steep, westward paleoslope promoted by east-ward offset of the locus of thermal uplift from the rift basin (i.e., a simple shear model of basin formation). In contrast to gravity-driven structures in most postrift settings, the Equatorial Guinea nappes developed at the close of the Aptian-Albian synrift episode in response to a growing bathymetric deep caused by rapid subsidence outpacing restricted sedimentation.

  7. Spatiotemporal relationships between earthquakes of the mid-Atlantic Ridge and the Atlantic continental margins

    Science.gov (United States)

    Bolarinwa, Oluwaseyi J.

    The seismicity of the mid Atlantic Ridge (MAR) was compared in space and time with the seismicity along the Atlantic continental margins of Europe, Africa, North America, the Carribean and South America in a bid to appraise the level of influence of the ridge push force at the MAR on the Atlantic coastal seismicity. By analyzing the spatial and temporal patterns of many earthquakes (along with the patterns in their stress directions) in diverse places with similar tectonic settings, it is hoped that patterns that might be found indicate some of the average properties of the forces that are causing the earthquakes. The spatial analysis of the dataset set used shows that areas with higher seismic moment release along the north MAR spatially correlate with areas with relatively lower seismic moment release along the north Atlantic continental margins (ACM) and vice versa. This inverse spatial correlation observed between MAR seismicity and ACM seismicity might be due to the time (likely a long time) it takes stress changes from segments of the MAR currently experiencing high seismic activity to propagate to the associated passive margin areas presently experiencing relatively low seismic activity. Furthermore, the number of Atlantic basin and Atlantic coast earthquakes occurring away from the MAR is observed to be independent of the proximity of earthquake's epicenters from the MAR axis. The effect of local stress as noted by Wysession et al. (1995) might have contributed to the independence of Atlantic basin and Atlantic coast earthquake proximity from the MAR. The Latchman (2011) observation of strong earthquakes on a specific section of the MAR being followed by earthquakes on Trinidad and Tobago was tested on other areas of the MAR and ACM. It was found that that the temporal delay observed by Latchman does not exist for the seismicity along other areas along the MAR and ACM. Within the time window used for this study, it appears that seismicity is occurring

  8. A White Atlantic? The Idea of American Art in Nineteenth-Century Britain

    Directory of Open Access Journals (Sweden)

    Tim Barringer

    2009-11-01

    Full Text Available This article begins with the contention that 'American art' is a powerful retrospective construction, rooted in the institutional practices of art history and museology. Through a focus on the experiences of expatriate American artists (John Singleton Copley and Benjamin West in London at the start of the nineteenth century, and the genre or landscape painting in transatlantic art (including the work of the British artist Thomas Cole, this essay exposes the complex and dynamic cultural interrelationship that existed between the United States and Europe in the period. It extends Paul Gilroy's and Joseph Roach's recent concept of the 'Black Atlantic', in which they argue that a single cultural zone brought together London and New Orleans, Kingston, Jamaica and the ports of the Ivory coast, to analyse the cultural and performative exchanges that were also taking place between America and Europe (particularly Great Britain, and that have hitherto been neglected in dominant art history narratives.

  9. From Europe to America: Pliocene to Recent trans-Atlantic expansion of cold-water North Atlantic molluscs

    Science.gov (United States)

    Vermeij, Geerat J

    2005-01-01

    Data on the geographical distribution, phylogeny and fossil record of cool-temperate North Atlantic shell-bearing molluscs that live in waters shallower than 100 m depth belong to two biogeographic provinces, one in eastern North America north of Cape Cod, the other in northern Europe. Amphi-Atlantic species, which are found in both provinces, comprise 30.8% of the 402 species in the northeastern Atlantic and 47.3% of the 262 species in the northwestern Atlantic. Some 54.8% of these amphi-Atlantic species have phylogenetic origins in the North Pacific. Comparisons among fossil Atlantic faunas show that amphi-Atlantic distributions became established in the Middle Pliocene (about 3.5 million years ago), and that all represent westward expansions of European taxa to North America. No American taxa spread eastward to Europe without human assistance. These results are in accord with previous phylogeographic studies among populations within several amphi-Atlantic species. Explanations for the unidirectional expansion of species across the Atlantic remain uncertain, but may include smaller size and greater prior extinction of the North American as compared to the European fauna and biased transport mechanisms. Destruction of the European source fauna may jeopardize faunas on both sides of the Atlantic. PMID:16271981

  10. Trophic ecology of Atlantic bluefin tuna Thunnus thynnus larvae.

    Science.gov (United States)

    Catalán, I A; Tejedor, A; Alemany, F; Reglero, P

    2011-05-01

    Feeding intensity, diet composition, selectivity, energy ingestion and dietary niche breadth of larval Atlantic bluefin tuna Thunnus thynnus were studied on the eastern (Mediterranean) spawning grounds of the species. Larval T. thynnus were collected in the Balearic Archipelago (north-west Mediterranean Sea) during 2004 and 2005 using surveys specific for larval scombrids. Larvae between 2·6 and 8·7 mm standard length (L(S) ) are diurnal feeders, and 94% of the guts collected during daylight hours were full. The mean ±s.d. number of prey per gut was 7·1 ± 5·7, with mean ±s.d. ranging from 3·0 ± 1·6 in the smallest T. thynnus larvae to 11·1 ± 5·8 in 5·0-6·0 mm L(S) larvae. Up to 21 prey were found in a single larval gut (5·0-6·0 mm L(S) ) at the end of the day. Larvae progressively selected larger prey and exhibited increased carbon content concurrent with preflexion development of feeding and locomotory structures. Larvae of 5·0-6·0 mm L(S) exhibited positive selection of cladocerans over other prey (Chesson's index), whereas copepod nauplii dominated the diets of earlier stages. The dietary niche breadth measured increased initially but decreased at c. 5·5 mm L(S) . Appendicularians were found in the diet of larger larval sizes, but no piscivory was observed. Results are discussed in light of the sparse existing data for larval T. thynnus and other larval tuna species. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles. No claim to original US government works.

  11. 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.)

  12. Displaced fracture through the anterior atlantal synchondrosis

    International Nuclear Information System (INIS)

    Thakar, Chrishan; Allibone, James; Harish, Srinivasan; Saifuddin, Asif

    2005-01-01

    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.)

  13. South Atlantic paleobathymetry since early Cretaceous.

    Science.gov (United States)

    Pérez-Díaz, Lucía; Eagles, Graeme

    2017-09-18

    We present early Cretaceous to present paleobathymetric reconstructions and quantitative uncertainty estimates for the South Atlantic, offering a strong basis for studies of paleocirculation, paleoclimate and paleobiogeography. Circulation in an initially salty and anoxic ocean, restricted by the topography of the Falkland Plateau, Rio Grande Ridge and Walvis Rise, favoured deposition of thick evaporites in shallow water of the Brazilian-Angolan margins. This ceased as seafloor spreading propagated northwards, opening an equatorial gateway to shallow and intermediate circulation. This gateway, together with subsiding volcano-tectonic barriers would have played a key role in Late Cretaceous climate changes. Later deepening and widening of the South Atlantic, together with gateway opening at Drake Passage would lead, by mid-Miocene (∼15 Ma) to the establishment of modern-style thermohaline circulation.

  14. Potential seaways across West Antarctica

    OpenAIRE

    Vaughan, David G.; Barnes, David K. A.; Fretwell, Peter T.; Bingham, Robert G.

    2011-01-01

    The West Antarctic ice sheet (WAIS) has long been considered vulnerable to rapid retreat and today parts are rapidly losing ice. Projection of future change in WAIS is, however, hampered by our poor understanding of past changes, especially during interglacial periods that could be analogs for the future, but which undoubtedly provide an opportunity for testing predictive models. We consider how ice-loss would open seaways across WAIS; these would likely alter Southern Ocean circulation and c...

  15. [Differential diagnoses of West syndrome].

    Science.gov (United States)

    Fejerman, Natalio

    2013-09-06

    This study describes the clinical and electroencephalographic characteristics of epileptic spasms, and more especially those that occur during the first two years of life (infantile spasms). West syndrome has been clearly defined as the association between infantile spasms with an electroencephalographic pattern of hypsarrhythmia. Although intellectual deficit appears in almost all cases in which infantile spasms are not controlled with medication, this is a developmental aspect of the condition and not a manifestation that must necessarily be present in order to define the syndrome. The analysis of the interictal and ictal electroencephalogram readings, together with the clinical characteristics of the spasms and the neurological examination of patients, provides some orientation as regards the causations. Despite the spectrum that the title of this work focuses on, the study does not cover the treatment of early infants with West syndrome. Emphasis is placed on the differential diagnoses of West syndrome with other epileptic syndromes that manifest in the first two years of life, and more especially with a series of abnormal non-epileptic motor phenomena that occur in early infants. All these last non-epileptic disorders are displayed in a table, but benign myoclonus of early infancy or Fejerman syndrome is given as a paradigmatic example for the differential diagnosis. The primordial aim is to prevent neurologically healthy early infants from receiving antiepileptic drugs and even adrenocorticotropic hormone or corticoids due to a mistaken diagnosis.

  16. Water-mass evolution in the Cretaceous Western Interior Seaway of North America and equatorial Atlantic

    Directory of Open Access Journals (Sweden)

    J. S. Eldrett

    2017-07-01

    Full Text Available The Late Cretaceous Epoch was characterized by major global perturbations in the carbon cycle, the most prominent occurring near the Cenomanian–Turonian (CT transition marked by Oceanic Anoxic Event 2 (OAE-2 at 94.9–93.7 Ma. The Cretaceous Western Interior Seaway (KWIS was one of several epicontinental seas in which a complex water-mass evolution was recorded in widespread sedimentary successions. This contribution integrates new data on the main components of organic matter, geochemistry, and stable isotopes along a north–south transect from the KWIS to the equatorial western Atlantic and Southern Ocean. In particular, cored sedimentary rocks from the Eagle Ford Group of west Texas (∼ 90–98 Ma demonstrate subtle temporal and spatial variations in palaeoenvironmental conditions and provide an important geographic constraint for interpreting water-mass evolution. High-latitude (boreal–austral, equatorial Atlantic Tethyan and locally sourced Western Interior Seaway water masses are distinguished by distinct palynological assemblages and geochemical signatures. The northward migration of an equatorial Atlantic Tethyan water mass into the KWIS occurred during the early–middle Cenomanian (98–95 Ma followed by a major re-organization during the latest Cenomanian–Turonian (95–94 Ma as a full connection with a northerly boreal water mass was established during peak transgression. This oceanographic change promoted de-stratification of the water column and improved oxygenation throughout the KWIS and as far south as the Demerara Rise off Suriname. In addition, the recorded decline in redox-sensitive trace metals during the onset of OAE-2 likely reflects a genuine oxygenation event related to open water-mass exchange and may have been complicated by variable contribution of organic matter from different sources (e.g. refractory/terrigenous material, requiring further investigation.

  17. Variability and trends of carbon parameters at a time series in the eastern tropical Atlantic

    Directory of Open Access Journals (Sweden)

    Nathalie Lefèvre

    2016-05-01

    Full Text Available Hourly fCO2 is recorded at a time series at the PIRATA buoy located at 6°S 10°W in the eastern tropical Atlantic since June 2006. This site is located south and west of the seasonal Atlantic cold tongue and is affected by its propagation from June to September. Using an alkalinity–salinity relationship determined for the eastern tropical Atlantic and the observed fCO2, pH and the inorganic carbon concentration are calculated. The time series is investigated to explore the intraseasonal, seasonal and interannual timescales for these parameters, and to detect any long-term trends. At intraseasonal timescales, fCO2 and pH are strongly correlated. On seasonal timescales, the correlation still holds between fCO2 and pH and their variations are in agreement with those of sea surface salinity. At interannual timescales, some important differences appear in 2011–2012: lower fCO2 and fluxes are observed from September to December 2011 and are explained by higher advection of salty waters at the mooring, in agreement with the wind. In early 2012, the anomaly is still present and associated with lower sea surface temperatures. No significant long-term trend is detected over the period 2006–2013 on CO2 and any other physical parameter. However, as atmospheric fCO2 is increasing over time, the outgassing of CO2 is reduced over the period 2006–2013 as the flux is mainly controlled by the difference of fCO2 between the ocean and the atmosphere. A longer time series is required to determine if any significant trend exists in this region.

  18. Pacific and Atlantic water influence on the Beaufort Sea slope tracked by epifaunal invertebrate biogeography

    Science.gov (United States)

    Bluhm, B.

    2016-02-01

    As an interior Arctic sea with a narrow shelf and a steep slope, the US Beaufort Sea is influenced by complex vertical and horizontal domains of water masses and current regimes. The benthic invertebrates inhabiting that area form communities that reflect the long-term (year to decadal) environmental conditions and waters mass source. During six expeditions over five years, we deployed plumb-staff beam trawls to collect epifauna invertebrates at >150 locations spanning the shelf and slope to 1000 m and across the primary water masses of the region (as defined by T/S). The >250 species sampled in this effort are dominated in species richness by crustaceans and gastropods, and in abundance and biomass by echinoderms and crustaceans, with proportional variations across water depths. We find strong turnover in species and/or community composition with water depth, and moderate shifts along the west-east axis. Depth-related species/community shifts are gradual, but most pronounced around the 20 m isobaths, at the shelf break (between 100 and 200 m) and between 350 and 500 m. Inshore of 20 m, the dynamic environment (ice gouging, variable salinity) results in a species-poor community. At locations deeper than 350 m, communities increasingly include species common in the Atlantic-influenced Arctic and Atlantic-boreal regions, roughly matching the transition from Pacific-origin to Atlantic-origin waters. We conclude that benthic community distribution can delineate boundaries in hydrographic conditions that are characteristic of different water mass types that reside on the shelf and slope of the Beaufort Sea.

  19. How Well Do Neodymium Isotopes Trace AMOC Mixing? A Test in the Southwest Atlantic

    Science.gov (United States)

    Wu, Y.; Goldstein, S. L.; Pena, L.; Hartman, A. E.; Rijkenberg, M. J. A.; De Baar, H. J. W.

    2014-12-01

    Neodymium (Nd) isotope ratios are used to trace past AMOC circulation, based on observations that seawater Nd isotope ratios effectively "fingerprint" water masses, and that over long water mass transport distances in deep seawater they reflect values expected from water mass mixing. Over the past several years, studies have increasingly focused on the potential of external addition of Nd along water mass transport paths (for example through "boundary exchange" with particulates or addition from groundwaters), thus challenging the idea that Nd isotopes behave "quasi-conservatively" in the oceans. The SW Atlantic, with the major water masses involved in the AMOC (southward flowing NADW, northward flowing AAIW and AABW), is arguably the best place on Earth to evaluate how well Nd isotopes trace water mass mixing, in order to clarify its value for following the AMOC through time. We will report Nd isotope ratios of seawater collected on the SW Atlantic meridional transect of the NIOZ West Atlantic GEOTRACES Cruise Leg 3 (RRS James Cook 057), which sampled seawater profiles and the sediment surface at 18 stations between 0-50°S. Most stations are sampled in the open ocean, providing a test of whether Nd isotopes show quasi-conservative mixing systematics away from continental margins. The cruise section also provides several opportunities to test the potential effects of external Nd input. For example, it transects the continental shelf in the far south, the Rio Grande Rise, volcanic seamounts, and the major geological age boundaries of South America. It also crosses the major Southern Hemisphere wind zones, allowing us to test the impacts of aeolian input, and inputs from major rivers (Parana-Paraguay, Sao Francisco, Amazon). All of these features have the potential to modify the seawater Nd isotope ratios, allowing us to determine if they add significant external Nd.

  20. North Atlantic, ITCZ, and Monsoonal Climate Links

    Science.gov (United States)

    Haug, G. H.; Deplazes, G.; Peterson, L. C.; Brauer, A.; Mingram, J.; Dulski, P.; Sigman, D. M.

    2008-12-01

    Major element chemistry and color data from sediment cores in the anoxic Cariaco Basin off Venezuela record with (sub)annual resolution large and abrupt shifts in the hydrologic cycle of the tropical Atlantic during the last 80 ka. These data suggest a direct connection between the position of the ITCZ over northern South America, the strength of trade winds, and the temperature gradient to the high northern latitudes, ENSO, and monsoonal climate in Asia. The mechanisms behind these decadal-scale ITCZ-monsoon swings can be further explored at major climate transitions such as the onset of Younger Dryas cooling at ~12.7 ka, one of the most abrupt climate changes observed in ice core, lake and marine records in the North Atlantic realm and much of the Northern Hemisphere. Annually laminated sediments from ideally record the dynamics of abrupt climate changes since seasonal deposition immediately responds to climate and varve counts accurately estimate the time of change. We compare sub-annual geochemical data from a lake in Western Germany, which provides one of the best-dated records currently available for this climate transition, with the new the Cariaco Basin record and a new and higher resolution record from Lake Huguang Maar in China, and the Greenland ice core record. The Lake Meerfelder Maar record indicates an abrupt increase in storminess, occurring from one year to the next at 12,678 ka BP, coincident with other observed climate changes in the region. We interpret this shift of the wintertime winds to signify an abrupt change in the North Atlantic westerlies to a stronger and more zonal jet. The observed wind shift provides the atmospheric mechanism for the strong temporal link between North Atlantic overturning and European climate during the last deglaciation, tightly coupled to ITCZ migrations observed in the Cariaco Basin sediments, and a stronger east Asian Monsoon winter monsoon as seen in lake Huguang Maar, when cave stalagmite oxygen isotope data

  1. NOAA Research Vessel Explores Atlantic Ocean Seamounts

    Science.gov (United States)

    Showstack, Randy

    2014-10-01

    Mike Ford, a biological oceanographer with the National Oceanic and Atmospheric Administration (NOAA), sat rapt in front of a bank of high-definition monitors. They provided live video and data feeds from a tethered pair of instrument-laden remotely operated vehicles (ROVs) that were descending 4692 meters on their deepest dive ever. Their target: an unnamed and unexplored New England seamount discovered in the North Atlantic last year.

  2. Brazil and the Vital South Atlantic

    Science.gov (United States)

    1988-09-01

    1984. Moneta, Carlos J. "Aspectos Conflictivos de las Relaciones Afro Latinoamericanas: Las Vivculaciones Politicas , Economicas y Militares de la...Descartes. Politica y Estrategia (No ataco, critico) Buenos Aires, Argentina. 1953 Douglas, Martin. "Naval Lessons from the South Atlantic " Jane’s Defence...January 1984 91 Goshko, John M. ’Australia deals a new blow to Anzus alliance. Washington Post, p. Al 7 February 1985. Grabendorff, Wolf. La Politica

  3. Tropical Atlantic biases and their relation to surface wind stress and terrestrial precipitation

    Science.gov (United States)

    Richter, Ingo; Xie, Shang-Ping; Wittenberg, Andrew T.; Masumoto, Yukio

    2012-03-01

    Most coupled general circulation models (GCMs) perform poorly in the tropical Atlantic in terms of climatological seasonal cycle and interannual variability. The reasons for this poor performance are investigated in a suite of sensitivity experiments with the Geophysical Fluid Dynamics Laboratory (GFDL) coupled GCM. The experiments show that a significant portion of the equatorial SST biases in the model is due to weaker than observed equatorial easterlies during boreal spring. Due to these weak easterlies, the tilt of the equatorial thermocline is reduced, with shoaling in the west and deepening in the east. The erroneously deep thermocline in the east prevents cold tongue formation in the following season despite vigorous upwelling, thus inhibiting the Bjerknes feedback. It is further shown that the surface wind errors are due, in part, to deficient precipitation over equatorial South America and excessive precipitation over equatorial Africa, which already exist in the uncoupled atmospheric GCM. Additional tests indicate that the precipitation biases are highly sensitive to land surface conditions such as albedo and soil moisture. This suggests that improving the representation of land surface processes in GCMs offers a way of improving their performance in the tropical Atlantic. The weaker than observed equatorial easterlies also contribute remotely, via equatorial and coastal Kelvin waves, to the severe warm SST biases along the southwest African coast. However, the strength of the subtropical anticyclone and along-shore winds also play an important role.

  4. Distribution and Characterization of Armillaria Complex in Atlantic Forest Ecosystems of Spain

    Directory of Open Access Journals (Sweden)

    Nebai Mesanza

    2017-06-01

    Full Text Available Armillaria root disease is a significant forest health concern in the Atlantic forest ecosystems in Spain. The damage occurs in conifers and hardwoods, causing especially high mortality in young trees in both native forests and plantations. In the present study, the distribution of Armillaria root disease in the forests and plantations of the Basque Country is reported. Armillaria spp. were more frequently isolated from stands with slopes of 20–30% and west orientation, acid soils with high permeability, deciduous hosts, and a rainfall average above 1800 mm. In a large-scale survey, 35% of the stands presented Armillaria structures and showed disease symptoms. Of the isolated Armillaria samples, 60% were identified using molecular methods as A. ostoyae, 24% as A. mellea, 14% as A. gallica, 1% as A. tabescens, and 1% as A. cepistipes. In a small scale sampling, population diversity was defined by somatic compatibility tests and Universally Primed-PCR technique. Finally, the pathogenicity of A. mellea, the species with the broadest host range, was determined on different tree species present in the Atlantic area of Spain in order to determine their resistance levels to Armillaria disease. A significant difference in disease severity was observed among tree species (p < 0.001, with Pinus radiata being the most susceptible tree species and Cryptomeria japonica the most resistant to A. mellea.

  5. Tropical Atlantic biases and their relation to surface wind stress and terrestrial precipitation

    Energy Technology Data Exchange (ETDEWEB)

    Richter, Ingo [Research Institute for Global Change, JAMSTEC, Yokohama (Japan); University of Hawaii at Manoa, International Pacific Research Center, Honolulu, HI (United States); Xie, Shang-Ping [University of Hawaii at Manoa, International Pacific Research Center, Honolulu, HI (United States); University of Hawaii at Manoa, Department of Meteorology, Honolulu, HI (United States); Wittenberg, Andrew T. [NOAA/Geophysical Fluid Dynamics Laboratory, Princeton, NJ (United States); Masumoto, Yukio [Research Institute for Global Change, JAMSTEC, Yokohama (Japan)

    2012-03-15

    Most coupled general circulation models (GCMs) perform poorly in the tropical Atlantic in terms of climatological seasonal cycle and interannual variability. The reasons for this poor performance are investigated in a suite of sensitivity experiments with the Geophysical Fluid Dynamics Laboratory (GFDL) coupled GCM. The experiments show that a significant portion of the equatorial SST biases in the model is due to weaker than observed equatorial easterlies during boreal spring. Due to these weak easterlies, the tilt of the equatorial thermocline is reduced, with shoaling in the west and deepening in the east. The erroneously deep thermocline in the east prevents cold tongue formation in the following season despite vigorous upwelling, thus inhibiting the Bjerknes feedback. It is further shown that the surface wind errors are due, in part, to deficient precipitation over equatorial South America and excessive precipitation over equatorial Africa, which already exist in the uncoupled atmospheric GCM. Additional tests indicate that the precipitation biases are highly sensitive to land surface conditions such as albedo and soil moisture. This suggests that improving the representation of land surface processes in GCMs offers a way of improving their performance in the tropical Atlantic. The weaker than observed equatorial easterlies also contribute remotely, via equatorial and coastal Kelvin waves, to the severe warm SST biases along the southwest African coast. However, the strength of the subtropical anticyclone and along-shore winds also play an important role. (orig.)

  6. Ukraine's Military between East and West

    National Research Council Canada - National Science Library

    Peterson Ulrich, Marybeth

    2007-01-01

    .... The pro-reform forces in power since the Orange Revolution would like to move Ukraine squarely into the Euro-Atlantic community with only limited deference to Russia in matters where Ukrainian...

  7. 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

  8. Sahel rainfall strength and onset improvements due to more realistic Atlantic cold tongue development in a climate model.

    Science.gov (United States)

    Steinig, S; Harlaß, J; Park, W; Latif, M

    2018-02-07

    The simulation of Sahel rainfall and its onset during the West African Monsoon (WAM) remains a challenge for current state-of-the-art climate models due to their persistent biases, especially in the tropical Atlantic region. Here we show that improved representation of Atlantic Cold Tongue (ACT) development is essential for a more realistic seasonal evolution of the WAM, which is due to a further inland migration of the precipitation maximum. The observed marked relationship between ACT development and Sahel rainfall onset only can be reproduced by a climate model, the Kiel Climate Model (KCM), when sufficiently high resolution in its atmospheric component is employed, enabling enhanced equatorial Atlantic interannual sea surface temperature variability in the ACT region relative to versions with coarser atmospheric resolution. The ACT/Sahel rainfall relationship in the model critically depends on the correct seasonal phase-locking of the interannual variability rather than on its magnitude. We compare the KCM results with those obtained from climate models participating in the Coupled Model Intercomparison Project phase 5 (CMIP5).

  9. Enhanced Influence of the Tropical Atlantic SST on the Western North Pacific Subtropical High after late 1970s

    Science.gov (United States)

    Hong, C. C.

    2015-12-01

    The western North Pacific subtropical high (WNPSH) in boreal summer shows a remarkable enhancement after the late 1970s. Whereas the sea surface temperature (SST) in the North Indian Ocean (NIO) and the equatorial eastern Pacific (EEP) had been noted to have remarkable local or remote effects on enhancing the WNPSH, the influence of the Atlantic SST, so far, is hardly explored. This article reports a new finding: enhanced relationship between the tropical Atlantic (TA)-SST and the WNPSH after the late 1970s. Regression study suggests that the warm TA-SST produced a zonally overturning circulation anomaly, with descending over the central equatorial Pacific and ascending over the tropical Atlantic/eastern Pacific. The anomalous descending over the central equatorial Pacific likely induced low-level anticyclonic anomaly to the west and therefore enhanced the WNPSH. One implication of this new finding is for predictability. The well-known "spring predictability barrier" (i.e., the influence of El Niño and Southern Oscillation (ENSO) falls dramatically during boreal spring) does not apply to the TA-SST/WNPSH relationship. Conversely, the TA-SST shows consistently high correlation starting from boreal spring when the ENSO influence continues declining. The TA-SST pushes the predictability of the WNPSH in boreal summer approximately one season earlier to boreal spring.

  10. 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...

  11. NEFSC 2005 Atlantic Herring Acoustic/Midwater Trawl Survey (DE0512, 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...

  12. 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...

  13. 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...

  14. NEFSC 2000 Atlantic Herring Acoustic/Midwater Trawl Survey (DE0008, 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...

  15. NEFSC 2001 Atlantic Herring Acoustic/Midwater Trawl Survey (DE0109, 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...

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. Diversification of West Nile virus in a subtropical region

    Directory of Open Access Journals (Sweden)

    Mores Christopher N

    2009-07-01

    Full Text Available Abstract Background West Nile virus (WNV has spread across North, Central, and South America since its introduction in 1999. At the start of this spread, Florida was considered a potentially important area with regards to transmission due to its geographic, climatological, and demographic conditions. Curiously, the anticipated high levels of transmission or disease outbreaks have not been observed. As other studies have predicted that the lack of intense WNV transmission is not due to vector incompetence, we sought to evaluate the role of viral strain diversity in WNV transmission in Florida. Therefore, a phylogentic analysis was carried out on several isolates collected from three distinct locations in Florida. Results Contrasting with a positive control collected in Indian River County, Florida during 2003 that contains the original NY99 genotype with valanine at amino acid 159 of the envelope region, all of the isolates collected in 2005 contain the WN02 genotype composed of a substation with alanine at that position indicating the window of introduction of the WN02 genotype occurred between 2003 and 2005. From the eight isolates collected in Duval, Indian River, and Manatee Counties; there is also a silent nucleotide substitution that differentiates the isolates collected on the Atlantic side of the state compared to the isolate collected on the Gulf side, which groups closer to isolates from other locations near the Gulf. Conclusion As a whole, the Florida isolates contained numerous variable nucleotide and amino acid sites from the reference sequences, as well as each other; indicating greater nucleotide diversity within the Florida 2005 isolates than within other regions. Finally, a series of three amino acid substitutions surrounding a set of histidines located in the envelope coding region that hypothesized to play a role in conformational changes was found in the isolate collected in Indian River County, perhaps changing the

  1. Atlantic water flow through the Faroese Channels

    Directory of Open Access Journals (Sweden)

    B. Hansen

    2017-11-01

    Full Text Available Through the Faroese Channels – the collective name for a system of channels linking the Faroe–Shetland Channel, Wyville Thomson Basin, and Faroe Bank Channel – there is a deep flow of cold waters from Arctic regions that exit the system as overflow through the Faroe Bank Channel and across the Wyville Thomson Ridge. The upper layers, in contrast, are dominated by warm, saline water masses from the southwest, termed Atlantic water. In spite of intensive research over more than a century, there are still open questions on the passage of these waters through the system with conflicting views in recent literature. Of special note is the suggestion that there is a flow of Atlantic water from the Faroe–Shetland Channel through the Faroe Bank Channel, which circles the Faroes over the slope region in a clockwise direction. Here, we combine the observational evidence from ship-borne hydrography, moored current measurements, surface drifter tracks, and satellite altimetry to address these questions and propose a general scheme for the Atlantic water flow through this channel system. We find no evidence for a continuous flow of Atlantic water from the Faroe–Shetland Channel to the Faroe Bank Channel over the Faroese slope. Rather, the southwestward-flowing water over the Faroese slope of the Faroe–Shetland Channel is totally recirculated within the combined area of the Faroe–Shetland Channel and Wyville Thomson Basin, except possibly for a small release in the form of eddies. This does not exclude a possible westward flow over the southern tip of the Faroe Shelf, but even including that, we estimate that the average volume transport of a Circum-Faroe Current does not exceed 0.5 Sv (1 Sv  =  106 m3 s−1. Also, there seems to be a persistent flow of Atlantic water from the western part of the Faroe Bank Channel into the Faroe–Shetland Channel that joins the Slope Current over the Scottish slope. These conclusions will affect

  2. Atlantic water flow through the Faroese Channels

    Science.gov (United States)

    Hansen, Bogi; Poulsen, Turið; Margretha Húsgarð Larsen, Karin; Hátún, Hjálmar; Østerhus, Svein; Darelius, Elin; Berx, Barbara; Quadfasel, Detlef; Jochumsen, Kerstin

    2017-11-01

    Through the Faroese Channels - the collective name for a system of channels linking the Faroe-Shetland Channel, Wyville Thomson Basin, and Faroe Bank Channel - there is a deep flow of cold waters from Arctic regions that exit the system as overflow through the Faroe Bank Channel and across the Wyville Thomson Ridge. The upper layers, in contrast, are dominated by warm, saline water masses from the southwest, termed Atlantic water. In spite of intensive research over more than a century, there are still open questions on the passage of these waters through the system with conflicting views in recent literature. Of special note is the suggestion that there is a flow of Atlantic water from the Faroe-Shetland Channel through the Faroe Bank Channel, which circles the Faroes over the slope region in a clockwise direction. Here, we combine the observational evidence from ship-borne hydrography, moored current measurements, surface drifter tracks, and satellite altimetry to address these questions and propose a general scheme for the Atlantic water flow through this channel system. We find no evidence for a continuous flow of Atlantic water from the Faroe-Shetland Channel to the Faroe Bank Channel over the Faroese slope. Rather, the southwestward-flowing water over the Faroese slope of the Faroe-Shetland Channel is totally recirculated within the combined area of the Faroe-Shetland Channel and Wyville Thomson Basin, except possibly for a small release in the form of eddies. This does not exclude a possible westward flow over the southern tip of the Faroe Shelf, but even including that, we estimate that the average volume transport of a Circum-Faroe Current does not exceed 0.5 Sv (1 Sv = 106 m3 s-1). Also, there seems to be a persistent flow of Atlantic water from the western part of the Faroe Bank Channel into the Faroe-Shetland Channel that joins the Slope Current over the Scottish slope. These conclusions will affect potential impacts from offshore activities in the

  3. Splitting of Atlantic water transport towards the Arctic Ocean into the Fram Strait and Barents Sea Branches - mechanisms and consequences

    Science.gov (United States)

    Beszczynska-Möller, Agnieszka; Skagseth, Øystein; von Appen, Wilken-Jon; Walczowski, Waldemar; Lien, Vidar

    2016-04-01

    The heat content in the Arctic Ocean is to a large extent determined by oceanic advection from the south. During the last two decades the extraordinary warm Atlantic water (AW) inflow has been reported to progress through the Nordic Seas into the Arctic Ocean. Warm anomalies can result from higher air temperatures (smaller heat loss) in the Nordic Seas, and/or from an increased oceanic advection. But the ultimate fate of warm anomalies of Atlantic origin depends strongly on their two possible pathways towards the Arctic Ocean. The AW temperature changes from 7-10°C at the entrance to the Nordic Seas, to 6-6.5°C in the Barents Sea opening and 3-3.5°C as the AW leaving Fram Strait enters the Arctic Ocean. When AW passes through the shallow Barents Sea, nearly all its heat is lost due to atmospheric cooling and AW looses its signature. In the deep Fram Strait the upper part of Atlantic water becomes transformed into a less saline and colder surface layer and thus AW preserves its warm core. A significant warming and high variability of AW volume transport was observed in two recent decades in the West Spitsbergen Current, representing the Fram Strait Branch of Atlantic inflow. The AW inflow through Fram Strait carries between 26 and 50 TW of heat into the Arctic Ocean. While the oceanic heat influx to the Barents Sea is of a similar order, the heat leaving it through the northern exit into the Arctic Ocean is negligible. The relative strength of two Atlantic water branches through Fram Strait and the Barents Sea governs the oceanic heat transport into the Arctic Ocean. According to recently proposed mechanism, the Atlantic water flow in the Barents Sea Branch is controlled by the strength of atmospheric low over the northern Barents Sea, acting through a wind-induced Ekman divergence, which intensifies eastward AW flow. The Atlantic water transport in the Fram Strait Branch is mainly forced by the large-scale low-pressure system over the eastern Norwegian and

  4. Sources and processes affecting the distribution of dissolved Nd isotopes and concentrations in the West Pacific

    Science.gov (United States)

    Behrens, Melanie K.; Pahnke, Katharina; Schnetger, Bernhard; Brumsack, Hans-Jürgen

    2018-02-01

    In the Atlantic, where deep circulation is vigorous, the dissolved neodymium (Nd) isotopic composition (expressed as ɛNd) is largely controlled by water mass mixing. In contrast, the factors influencing the ɛNd distribution in the Pacific, marked by sluggish circulation, is not clear yet. Indication for regional overprints in the Pacific is given based on its bordering volcanic islands. Our study aims to clarify the impact and relative importance of different Nd sources (rivers, volcanic islands), vertical (bio)geochemical processes and lateral water mass transport in controlling dissolved ɛNd and Nd concentration ([Nd]) distributions in the West Pacific between South Korea and Fiji. We find indication for unradiogenic continental input from South Korean and Chinese rivers to the East China Sea. In the tropical West Pacific, volcanic islands supply Nd to surface and subsurface waters and modify their ɛNd to radiogenic values of up to +0.7. These radiogenic signatures allow detailed tracing of currents flowing to the east and differentiation from westward currents with open ocean Pacific ɛNd composition in the complex tropical Pacific zonal current system. Modified radiogenic ɛNd of West Pacific intermediate to bottom waters upstream or within our section also indicates non-conservative behavior of ɛNd due to boundary exchange at volcanic island margins, submarine ridges, and with hydrothermal particles. Only subsurface to deep waters (3000 m) in the open Northwest Pacific show conservative behavior of ɛNd. In contrast, we find a striking correlation of extremely low (down to 2.77 pmol/kg Nd) and laterally constant [Nd] with the high-salinity North and South Pacific Tropical Water, indicating lateral transport of preformed [Nd] from the North and South Pacific subtropical gyres into the study area. This observation also explains the previously observed low subsurface [Nd] in the tropical West Pacific. Similarly, Western South Pacific Central Water, Antarctic

  5. A genetic comparison of West Greenland and Baffin Island (Canada walruses: Management implications

    Directory of Open Access Journals (Sweden)

    Liselotte Wesley Andersen

    2014-12-01

    Full Text Available Until recently Atlantic walruses (Odobenus rosmarus rosmarus have been subject to relatively intense exploitation in West Greenland. Animals in this stock have also been hunted in Nunavut/Canada. However, the demographic identity of these animals and their connection with walruses in neighbouring areas is poorly resolved, hampering the determination of sustainable harvest levels. It has been suggested that walruses in West Greenland are genetically linked with walruses at SE Baffin Island (Canada where they are also hunted for subsistence purposes. To determine the relationship(s between walruses in these areas we conducted a genetic analysis including recent samples from West Greenland, Southeast Baffin Island in western Davis Strait, Hudson Strait in Canada and Northwest Greenland in northern Baffin Bay. Seventeen microsatellite markers were applied to all samples. Walruses in West Greenland and at Southeast Baffin Island did not differ from each other and therefore may be regarded as belonging to the same stock. However, walruses in these two areas differed genetically from both Northwest Greenland and Hudson Strait walruses. These findings support (1 that there are subunits within the range of walruses in the Hudson Strait-Davis Strait-Baffin Bay region and (2 that walruses along E Baffin Island and W Greenland constitute a common population that receive some influx from Hudson Strait. Thus, sustainable catch levels in Southeast Baffin Island (Nunavut and in West Greenland must be set in light of the finding that they belong to the same stock, which is exploited in these two areas. This requires Canadian-Greenlandic co-management of the W Greenland-SE Baffin Island walrus stock.

  6. Drought modes in West Africa and how well CORDEX RCMs simulate them

    Science.gov (United States)

    Diasso, Ulrich; Abiodun, Babatunde J.

    2017-04-01

    This study presents the spatial-temporal structure of droughts in West Africa and evaluates the capability of CORDEX regional climate models in simulating the droughts. The study characterize droughts with the standardized evapo-transpiration index (SPEI) computed using the monthly rainfall and temperature data from the Climatic Research Unit (CRU) and CORDEX models simulation datasets. To obtain the spatial-temporal structure of the droughts, we applied the principal component analysis on the observed and simulated SPEIs and retained the first four principal factors as the leading drought modes over West Africa. The relationship between the drought modes and atmospheric teleconnections was studied using wavelet coherence analysis, while the ability of the CORDEX models to simulate the drought modes was quantified with correlation analysis. The analysis of the relationship between drought modes and atmospheric teleconnections is based on SPEI from observation dataset (CRU). The study shows that about 60 % of spatial-temporal variability in SPEI over West Africa can be grouped into four drought modes. The first drought mode features drought over east Sahel, the second over west Sahel, the third over the Savanna, and the fourth over the Guinea coast. Each drought mode is linked to sea surface temperature anomalies (SSTAs) over tropical areas of Pacific, Atlantic, and Indian Oceans. Most CORDEX models reproduce at least two of the drought modes, but only two models (REMO and CNRM) reproduce all the four drought modes. REMO and WRF give the best simulation of the seasonal variation of the drought mode over the Sahel in March-May and June-August seasons, while CNRM gives the best simulation of seasonal variation in the drought pattern over the Savanna. Results of this study may guide in selecting appropriate CORDEX models for seasonal prediction of droughts and for downscaling projected impacts of global warming on droughts in West Africa.

  7. 76 FR 10887 - Fisheries of the South Atlantic and Gulf of Mexico; South Atlantic Fishery Management Council...

    Science.gov (United States)

    2011-02-28

    ... Mexico; South Atlantic Fishery Management Council; Public Meeting AGENCY: National Marine Fisheries... at the Crowne Plaza Hotel, 4831 Tanger Outlet Boulevard, North Charleston, SC 29418; telephone: (843...

  8. 77 FR 58981 - Fisheries of the South Atlantic and Gulf of Mexico; South Atlantic Fishery Management Council...

    Science.gov (United States)

    2012-09-25

    ... Mexico; South Atlantic Fishery Management Council (SAFMC); Public Meeting AGENCY: National Marine... Plaza, 4831 Tanger Outlet Boulevard, North Charleston, SC 29418; telephone: (843) 744- 4422. FOR FURTHER...

  9. 77 FR 60967 - Fisheries of the South Atlantic and Gulf of Mexico; South Atlantic Fishery Management Council...

    Science.gov (United States)

    2012-10-05

    ... Mexico; South Atlantic Fishery Management Council (Council) Scientific and Statistical Committee (SSC... Tanger Outlet Boulevard, North Charleston SC; telephone: (877) 744-4422. FOR FURTHER INFORMATION CONTACT...

  10. Potential links between the North Atlantic Oscillation and decreasing precipitation and runoff on a Mediterranean area

    Science.gov (United States)

    Montaldo, Nicola; Sarigu, Alessio

    2017-10-01

    In the Mediterranean region, the reduction in precipitation and warmer temperatures is generating a desertification process, with dramatic consequences for both agriculture and the sustainability of water resources. On the island of Sardinia (Italy), the decrease in runoff impacts the management of water resources, resulting in water supply restrictions even for domestic consumption. In the 10 Sardinian basins with a longer database (at least 40 complete years of data, including data from the past 10 years), runoff decreased drastically over the 1975-2010 period, with mean yearly runoff reduced by more than 40% compared to the previous 1922-1974 period. Trends in yearly runoff are negative, with Mann-Kendall τ values ranging from -0.39 to -0.2. Decreasing winter precipitation over the 1975-2010 period everywhere on Sardinia island has led to these decreases in runoff, as most yearly runoff in the Sardinian basins (70% on average) is produced by winter precipitation due to the seasonality typical of the Mediterranean climate regime. The trend in winter precipitation is not homogenous; the negative trend is higher (around -0.25) on the west Sardinian coast, becoming lower across the island toward the east coast (around -0.14). Winter precipitation is highly correlated with the North Atlantic Oscillation (NAO), a weather phenomenon in the North Atlantic Ocean that controls the direction and strength of westerly winds and storm tracks into Europe. High negative correlations (up to -0.45) between winter NAO index and winter precipitation are estimated along the west coast. Meanwhile, these correlations decrease east across the island toward the high mountain in the center of Sardinia, reaching the lowest values along the east coast (about -0.25). The generally decreasing correlation between winter NAO index and winter precipitation in the longitudinal direction (from the North Atlantic dipole to the east) here accelerates due to local-scale orographic effects that

  11. 2 SDI, alliance coherence, and East-West nuclear stability

    International Nuclear Information System (INIS)

    Kolodzie, E.A.

    1988-01-01

    The nuclear modernization programme, offensive and defensive, now being implemented or seriously proposed by the Western nuclear states and the Soviet Union pose critical problems for the stability of the European and global nuclear balance. The Reagan administration's Strategic Defence Initiative (SDI) and the dramatic growth of British and French nuclear capabilities add new strains on the arms race now underway between the superpowers. Current and emerging instabilities must be addressed promptly along a broad political front, within and outside the framework of the Atlantic Alliance, before they further split the alliance and damage efforts---principally those being pursued at Geneva in the superpower arms control talks---to manage the nuclear balance and the conflicts that divide the two blocs in Europe and elsewhere. The first part of this paper diagnoses the disturbing elements of the evolving nuclear environment which promotes instability. The second suggests an approach -- complex bilateralism -- that might be employed to bring these destabilizing trends under control to promote the development of more coherent, cohesive, and mutually confident alliance strategic policies than exist today and to enhance East-West stability

  12. Alternating current for the West

    International Nuclear Information System (INIS)

    2006-01-01

    In the framework of the reactor EPR construction in the Manche, the authors wonder on the pertinence of this energy choice for the economy and the environment of the West France. They show that there is an alternative to this choice. In a first part a state of the situation concerning the electricity supply and demand in the region is detailed. Then from the local potential of renewable electric power production and the electricity conservation, they propose many concrete actions. (A.L.B.)

  13. Permafrost degradation in West Greenland

    DEFF Research Database (Denmark)

    Foged, Niels Nielsen; Ingeman-Nielsen, Thomas

    2012-01-01

    Important aspects of civil engineering in West Greenland relate to the presence of permafrost and mapping of the annual and future changes in the active layer due to the ongoing climatically changes in the Arctic. The Arctic Technology Centre (ARTEK) has worked more than 10 years on this topic...... parameters. It is planned as decision and planning tool for town planners and engineers in local municipality governments and to consulting engineers and contractors in Greenland, which also may be used in other arctic regions. Risk is classified in four categories: Low, Limited, Medium and High based...

  14. 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.)

  15. 76 FR 7547 - Atlantic Highly Migratory Species; Meeting of the Atlantic Highly Migratory Species Advisory Panel

    Science.gov (United States)

    2011-02-10

    ... of 2010 ICCAT measures, an update on recreational monitoring methods for HMS fisheries, vessel monitoring systems and potential regulatory changes, a summary of the Future of the Shark Fishery workshops... of Atlantic HMS fisheries, including electronic dealer reporting, revitalizing the swordfish fishery...

  16. 78 FR 65974 - Atlantic Highly Migratory Species; Advisory Panel for Atlantic Highly Migratory Species Southeast...

    Science.gov (United States)

    2013-11-04

    ... Organization, Practices, and Procedures by any of the following methods: Email: [email protected] . Mail... environmental community active in the conservation and management of Atlantic sharks, and the academic community... qualifications; and 4. A written commitment that the applicant or nominee shall participate actively and in good...

  17. 77 FR 69596 - Atlantic Highly Migratory Species; Advisory Panel for Atlantic Highly Migratory Species Southeast...

    Science.gov (United States)

    2012-11-20

    ... Organization, Practices, and Procedures by any of the following methods: Email: [email protected] . Mail... conservation and management of Atlantic sharks, and the academic community that have relevant expertise either... shall participate actively and in good faith in the tasks of the SEDAR Pool, as requested. C. Meeting...

  18. 76 FR 70064 - Atlantic Highly Migratory Species; Update to Information on the Effective Date of Atlantic...

    Science.gov (United States)

    2011-11-10

    ... provisions, and only after ESA Section 7 consultation is completed. Notice of the effective date will be.... 110912579-1627-01] RIN 0648-BB43 Atlantic Highly Migratory Species; Update to Information on the Effective.... SUMMARY: NMFS is updating the anticipated effective date of smoothhound shark management measures...

  19. 77 FR 44161 - Atlantic Highly Migratory Species; 2012 Atlantic Bluefin Tuna Quota Specifications

    Science.gov (United States)

    2012-07-27

    ... fighting among themselves while eastern Atlantic and Mediterranean BFT fishermen benefit. Some commenters... that assume the number of BFT yearlings (one-year- old fish) in 2011 would be reduced by 20 percent... conducted projections using the `MAST' model (Multistock Age-Structured Tag-Integrated assessment model...

  20. 78 FR 24148 - Atlantic Highly Migratory Species; Atlantic Shark Management Measures

    Science.gov (United States)

    2013-04-24

    ... Species; Atlantic Shark Management Measures AGENCY: National Marine Fisheries Service (NMFS), National... Plan (FMP) to address the results of recent shark stock assessments for several shark species, including dusky sharks. In that notice, based on the 2010/2011 Southeast Data, Assessment and Review (SEDAR...

  1. 75 FR 50715 - Atlantic Highly Migratory Species; Atlantic Shark Management Measures; Amendment 3

    Science.gov (United States)

    2010-08-17

    ... Migratory Species; Atlantic Shark Management Measures; Amendment 3 AGENCY: National Marine Fisheries Service.... This change ensures that the process is preserved for adjusting annual shark quotas based on over- and..., among other things, pelagic shark quotas and annual quota adjustments. The instructions, however...

  2. 78 FR 11809 - Fisheries of the Northeastern United States; Atlantic Bluefish Fishery; 2013-2014 Atlantic...

    Science.gov (United States)

    2013-02-20

    ... Ticket reports were used to identify 768 vessels that landed bluefish in North Carolina and 791 vessels... alternative, using Northeast dealer reports and South Atlantic Trip Ticket reports. Under Alternative 1, the... impacted with revenue reductions of 5 percent or more, 22 percent had gross sales of $1,000 or less and 44...

  3. 77 FR 8776 - Fisheries of the Northeastern United States; Atlantic Bluefish Fishery; 2012 Atlantic Bluefish...

    Science.gov (United States)

    2012-02-15

    .... South Atlantic Trip Ticket reports were used to identify 732 vessels \\1\\ that landed bluefish in North... Ticket reports. Under Alternative 1, the recommended commercial quota for 2012 is approximately 40... likely to be impacted with revenue reductions of 5 percent or more, 34 percent had gross sales of $1,000...

  4. 75 FR 10450 - Fisheries of the Northeastern United States; Atlantic Bluefish Fisheries; 2010 Atlantic Bluefish...

    Science.gov (United States)

    2010-03-08

    ... fishery participation in South Carolina, Georgia, or Florida. South Atlantic Trip Ticket reports were used... Ticket reports. The analysis projected that there would be no revenue change for 493 vessels, while 124... vessels that may experience revenue losses of more than 5 percent, 56 percent had gross sales of $1,000 or...

  5. The Equatorial Undercurrent in the central Atlantic and its relation to tropical Atlantic variability

    NARCIS (Netherlands)

    Brandt, Peter; Funk, Andreas; Tantet, Alexis; Johns, William E.; Fischer, Jürgen

    2014-01-01

    Seasonal to interannual variations of the Equatorial Undercurrent (EUC) in the central Atlantic at 23?Ware studied using shipboard observation taken during the period 1999–2011 as well as moored velocity time series covering the period May 2005–June 2011. The sea- sonal variations are dominated by

  6. Holocene mangrove swamps of West Africa sedimentology and soils

    Science.gov (United States)

    Marius, C.; Lucas, J.

    The mangrove swamps of West African Coast belong to the Atlantic type which is characterized by a small number of species. They colonize tidal environments which are dissected by numerous meandering tidal channels and are presently subject to a low rate of sediment accumulation. The mangrove vegetation exhibits a characteristic zonation pattern that basically reflects the adaptation of the various species to saline conditions. The typical zonation sequence is: Rhizophora racemosa (or Rh. mangle), Rh. mangle + Avicennia africana, Avicennia, flooded tanne, barren tanne, herbaceous tanne. The tannes are generated by aridic climatic conditions, heavy soil and water salt content, and are, in a way a peculiar feature of mangrove swamps in West Africa. The sediment colonized by the mangroves is relatively homogenous. Mineralogically, they are dominated by quartz and clay to which are associated halite, pyrite and jarosite. The clay suite is mainly composed of smectite and kaolinite. Smectite is predominant in the inlet areas and is replaced inland by kaolinite. Chemically, the sediments contain very low amounts of Ca, bases and trace elements. The mangrove swamp floodwaters have a chemical composition similar to that of seawater. It is dominated by sodium and chloride. Morphologically, the ripening of the soils appears with a chestnut mash colour horizon and buttery consistency in relation with the decomposition of fibrous roots of Rhizophora and also with pale yellow jarosite mottles in the top horizons of the tanne profiles due to the oxidation of pyrine. The two main properties of the mangrove soils of West Africa are acidity and salinity; the first is related to the high content of sulphur and the second to the sea influence. The acidity has to be connected mainly to the Rhizophora vegetation whose the root system is a real trap for catching the pyrites resulting from the reduction of the sulphates of sea water by the sulphate reducing bacteria, in a reduced

  7. MeshAtlantic - Mapping Atlantic Area Seabed Habitats For Better Marine Management

    Science.gov (United States)

    McGrath, F.

    2016-02-01

    MeshAtlantic is an EU funded project (INTERREG IVB, 2010-2013) which has provided a harmonised seabed habitat map of the coastal and shelf areas of the Northeast Atlantic. The primary aim of the project was to aid the development of sustainable marine management plans at both regional and European levels. It involved the collation of habitat mapping information across several countries, including Ireland, France, Spain and Portugal as well as acquisition of new data in MPAs in each country. MeshAtlantic has acted as a focal point for collation and standardization of these datasets at an international level. It has also resulted in improved interaction between the European agencies responsible for seabed mapping and stakeholders. The collation of these data has also resulted in close collaboration with other EU funded projects (e.g. EMODNET). The key outputs of the project are three different sets of maps harmonized and classified using EUNIS across the project area. These are: 1. Pre-existing habitat maps that have been enhanced and harmonized 2. Detailed national and transnational habitat maps covering a limited set of Natura 2000 sites 3. A broad-scale modelled habitat map extending from Ireland to Potrtugal (including the Azores) The outputs of the project in Ireland include acquisition of new data in Kenmare Bay, a EUNIS habitat map for Kenmare Bay, direct support of monitoring work in the WFD, a collated habitat map for a significant part of Irelands seabed, and collation of existing habitat maps and source data. MeshAtlantic was supported by INFOMAR, Irelands national seabed mapping programme. Involvement in MeshAtlantic has facilitated leveraging of extra resources in order to discharge a programme of data collation which otherwise could not have been carried out. This paper will focus on how MeshAtlantic promoted harmonised production and use of marine habitat maps covering the Atlantic Area, and look at the approaches adopted to delivering habitat maps for

  8. The North Atlantic Oscillation, Surface Current Velocities, and SST Changes in the Subpolar North Atlantic.

    Science.gov (United States)

    Flatau, Maria K.; Talley, Lynne; Niiler, Pearn P.

    2003-07-01

    Changes in surface circulation in the subpolar North Atlantic are documented for the recent interannual switch in the North Atlantic Oscillation (NAO) index from positive values in the early 1990s to negative values in 1995/96. Data from Lagrangian drifters, which were deployed in the North Atlantic from 1992 to 1998, were used to compute the mean and varying surface currents. NCEP winds were used to calculate the Ekman component, allowing isolation of the geostrophic currents. The mean Ekman velocities are considerably smaller than the mean total velocities that resemble historical analyses. The northeastward flow of the North Atlantic Current is organized into three strong cores associated with topography: along the eastern boundary in Rockall Trough, in the Iceland Basin (the subpolar front), and on the western flank of the Reykjanes Ridge (Irminger Current). The last is isolated in this Eulerian mean from the rest of the North Atlantic Current by a region of weak velocities on the east side of the Reykjanes Ridge.The drifter results during the two different NAO periods are compared with geostrophic flow changes calculated from the NASA/Pathfinder monthly gridded sea surface height (SSH) variability products and the Advanced Very High Resolution Radiometer (AVHRR) SST data. During the positive NAO years the northeastward flow in the North Atlantic Current appeared stronger and the circulation in the cyclonic gyre in the Irminger Basin became more intense. This was consistent with the geostrophic velocities calculated from altimetry data and surface temperature changes from AVHRR SST data, which show that during the positive NAO years, with stronger westerlies, the subpolar front was sharper and located farther east. SST gradients intensified in the North Atlantic Current, Irminger Basin, and east of the Shetland Islands during the positive NAO phase, associated with stronger currents. SST differences between positive and negative NAO years were consistent with

  9. Tropical Cyclone Activity in the North Atlantic Basin During the Weather Satellite Era, 1960-2014

    Science.gov (United States)

    Wilson, Robert M.

    2016-01-01

    This Technical Publication (TP) represents an extension of previous work concerning the tropical cyclone activity in the North Atlantic basin during the weather satellite era, 1960-2014, in particular, that of an article published in The Journal of the Alabama Academy of Science. With the launch of the TIROS-1 polar-orbiting satellite in April 1960, a new era of global weather observation and monitoring began. Prior to this, the conditions of the North Atlantic basin were determined only from ship reports, island reports, and long-range aircraft reconnaissance. Consequently, storms that formed far from land, away from shipping lanes, and beyond the reach of aircraft possibly could be missed altogether, thereby leading to an underestimate of the true number of tropical cyclones forming in the basin. Additionally, new analysis techniques have come into use which sometimes has led to the inclusion of one or more storms at the end of a nominal hurricane season that otherwise would not have been included. In this TP, examined are the yearly (or seasonal) and 10-year moving average (10-year moving average) values of the (1) first storm day (FSD), last storm day (LSD), and length of season (LOS); (2) frequencies of tropical cyclones (by class); (3) average peak 1-minute sustained wind speed () and average lowest pressure (); (4) average genesis location in terms of north latitudinal () and west longitudinal () positions; (5) sum and average power dissipation index (); (6) sum and average accumulated cyclone energy (); (7) sum and average number of storm days (); (8) sum of the number of hurricane days (NHD) and number of major hurricane days (NMHD); (9) net tropical cyclone activity index (NTCA); (10) largest individual storm (LIS) PWS, LP, PDI, ACE, NSD, NHD, NMHD; and (11) number of category 4 and 5 hurricanes (N4/5). Also examined are the December-May (D-M) and June-November (J-N) averages and 10-year moving average values of several climatic factors, including the (1

  10. 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.

  11. 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.

  12. Spatial and temporal distribution of North Atlantic tropical cyclones ...

    African Journals Online (AJOL)

    month of genesis and their lifecycles and to study the role of African Easterly Waves (AEWs) in North Atlantic cyclogenesis. Between 1980 and 2004, 269 tropical cyclones (TCs) were formed over the North Atlantic, 77% of which occurred during the August-October period and 95% of major hurricanes (TCs in which the ...

  13. K West Basin canister survey

    International Nuclear Information System (INIS)

    Pitner, A.L.

    1998-01-01

    A survey was conducted of the K West Basin to determine the distribution of canister types that contain the irradiated N Reactor fuel. An underwater camera was used to conduct the survey during June 1998, and the results were recorded on videotape. A full row-by-row survey of the entire basin was performed, with the distinction between aluminum and stainless steel Mark 1 canisters made by the presence or absence of steel rings on the canister trunions (aluminum canisters have the steel rings). The results of the survey are presented in tables and figures. Grid maps of the three bays show the canister lid ID number and the canister type in each location that contained fuel. The following abbreviations are used in the grid maps for canister type designation: IA = Mark 1 aluminum, IS = Mark 1 stainless steel, and 2 = Mark 2 stainless steel. An overall summary of the canister distribution survey is presented in Table 1. The total number of canisters found to contain fuel was 3842, with 20% being Mark 1 Al, 25% being Mark 1 SS, and 55% being Mark 2 SS. The aluminum canisters were predominantly located in the East and West bays of the basin

  14. North Atlantic octocorals: Distribution, Ecology and Phylogenetics

    OpenAIRE

    Morris, Kirsty Janet

    2011-01-01

    Most studies of deep-sea benthic fauna have concentrated on soft sediments with little sampling in rocky areas and even less on non-vent mid-ocean ridges and within submarine canyons, mainly as a result of difficulty accessing them. To assess the distribution and abundance of cold-water corals along an Axial Volcanic Ridges along the Mid-Atlantic ridge at 45oN 27oW, and within the Whittard Canyon along the Irish Margin video footage from the ROV Isis taken during a three scientific cruises wa...

  15. Whales before whaling in the North Atlantic.

    Science.gov (United States)

    Roman, Joe; Palumbi, Stephen R

    2003-07-25

    It is well known that hunting dramatically reduced all baleen whale populations, yet reliable estimates of former whale abundances are elusive. Based on coalescent models for mitochondrial DNA sequence variation, the genetic diversity of North Atlantic whales suggests population sizes of approximately 240,000 humpback, 360,000 fin, and 265,000 minke whales. Estimates for fin and humpback whales are far greater than those previously calculated for prewhaling populations and 6 to 20 times higher than present-day population estimates. Such discrepancies suggest the need for a quantitative reevaluation of historical whale populations and a fundamental revision in our conception of the natural state of the oceans.

  16. 78 FR 22193 - Special Local Regulations; West Palm Beach Triathlon Championship, Intracoastal Waterway; West...

    Science.gov (United States)

    2013-04-15

    ...-AA08 Special Local Regulations; West Palm Beach Triathlon Championship, Intracoastal Waterway; West Palm Beach, FL AGENCY: Coast Guard, DHS. ACTION: Temporary Final Rule. SUMMARY: The Coast Guard is establishing a special local regulation on the Intracoastal Waterway, in West Palm Beach, Florida, during the...

  17. 78 FR 2916 - Special Local Regulation; West Palm Beach Triathlon Championship, Intracoastal Waterway, West...

    Science.gov (United States)

    2013-01-15

    ... 1625-AA08 Special Local Regulation; West Palm Beach Triathlon Championship, Intracoastal Waterway, West Palm Beach, FL AGENCY: Coast Guard, DHS. ACTION: Notice of proposed rulemaking. SUMMARY: The Coast... Palm Beach, Florida, during the West Palm Beach Triathlon Championship, on Saturday, June 1, 2013...

  18. Growth and decay of the Equatorial Atlantic SST mode by means of closed heat budget in a coupled General Circulation Model

    Directory of Open Access Journals (Sweden)

    Irene ePolo

    2015-07-01

    Full Text Available Tropical Atlantic variability is strongly biased in coupled General Circulation Models (GCM. Most of the models present a mean Sea Surface Temperature (SST bias pattern that resembles the leading mode of inter-annual SST variability. Thus, understanding the causes of the main mode of variability of the system is crucial. A GCM control simulation with the IPSL-CM4 model as part of the CMIP3 experiment has been analyzed. Mixed layer heat budget decomposition has revealed the processes involved in the origin and development of the leading inter-annual variability mode which is defined over the Equatorial Atlantic (hereafter EA mode. In comparison with the observations, it is found a reversal in the anomalous SST evolution of the EA mode: from west equator to southeast in the simulation, while in the observations is the opposite. Nevertheless, despite the biases over the eastern equator and the African coast in boreal summer, the seasonality of the inter-annual variability is well reproduced in the model. The triggering of the EA mode is found to be related to vertical entrainment at the equator as well as to upwelling along South African coast. The damping is related to the air-sea heat fluxes and oceanic horizontal terms. As in the observation, this EA mode exerts an impact on the West African and Brazilian rainfall variability. Therefore, the correct simulation of EA amplitude and time evolution is the key for a correct rainfall prediction over tropical Atlantic. In addition to that, identification of processes which are responsible for the tropical Atlantic biases in GCMs is an important element in order to improve the current global prediction systems.

  19. Rb-Sr, 87Sr/86Sr isotope system as an index of provenance of continental dusts in the open Atlantic ocean

    International Nuclear Information System (INIS)

    Biscaye, P.E.; Chesselet, Roger; Prospero, J.M.

    1974-01-01

    The Rb-Sr, Sr-isotope system technique was applied to samples of water-insoluble atmospheric dust to test its utility in answering two questions: 1) the continental provenance of the dust, and 2) the relative importance of eolian versus other contributions to deep-sea sediments. Samples of atmospheric dust were taken on Whatman filters during two Atlantic cruises: a north-south section from May to October 1971 (Dakar-Walvis Bay-Azores) and an east-west section from September to October 1972 (Barbados-Dakar). In addition several other filter samples from the Equatorial Atlantic and mesh samples from Barbados were analyzed. The overall pattern of dust concentrations is consistent with the well-known strong Saharan plume at 10-15 deg N latitude and extends westward to the Caribbean with average concentrations in excess of 10 μg/m 3 . The north-south track was relatively near the African coast but permitted some definition of the decrease of dust concentrations north (to about 1 μg/m 3 ) and south (to 3 ) of the main plume. From the 87 Sr/ 86 Sr ratios we distinguish the dusts from the Saharan and a second plume, probably from the Kalahari Desert of southwestern Africa. The ratios of dusts in the Saharan plume are indistinguishable from deep-sea sediments in this latitude band. Adding Rb/Sr to the Sr-isotope ratios in an isochronous plot, however, permits distinction between the dusts and deep-sea sediments east of the Mid-Atlantic Ridge, and from the sediments underlying the Saharan plume but west of the Ridge. The authors conclude that, west of the Ridge, the colian dust contribution to the sediments is strongly diluted by non-eolian sediment sources, confirming with an independant provenance characteristic conclusions derived from sediment mineralogical data [fr

  20. Basement control in the development of the early cretaceous West and Central African rift system

    Science.gov (United States)

    Maurin, Jean-Christophe; Guiraud, René

    1993-12-01

    The structural framework of the Precambrian basement of the West and Central African Rift System (WCARS) is described in order to examine the role of ancient structures in the development of this Early Cretaceous rift system. Basement structures are represented in the region by large Pan-African mobile belts (built at ca. 600 Ma) surrounding the > 2 Ga West African, Congo and Sao Francisco cratons. Except for the small Gao trough (eastern Mali) located near the contact nappe of the Pan-African Iforas suture zone along the edge of the West African craton, the entire WCARS is located within the internal domains of the Pan-African mobile belts. Within these domains, two main structural features occur as the main basement control of the WCARS: (1) an extensive network of near vertical shear zones which trend north-south through the Congo, Brazil, Nigeria, Niger and Algeria, and roughly east-west through northeastern Brazil and Central Africa. The shear zones correspond to intra-continental strike-slip faults which accompanied the oblique collision between the West African, Congo, and Sao Francisco cratons during the Late Proterozoic; (2) a steep metamorphic NW-SE-trending belt which corresponds to a pre-Pan-African (ca. 730 Ma) ophiolitic suture zone along the eastern edge of the Trans-Saharian mobile belt. The post-Pan-African magmatic and tectonic evolution of the basement is also described in order to examine the state of the lithosphere prior to the break-up which occurred in the earliest Cretaceous. After the Pan-African thermo-tectonic event, the basement of the WCARS experienced a long period of intra-plate magmatic activity. This widespread magmatism in part relates to the activity of intra-plate hotspots which have controlled relative uplift, subsidence and occasionally block faulting. During the Paleozoic and the early Mesozoic, this tectonic activity was restricted to west of the Hoggar, west of Aïr and northern Cameroon. During the Late Jurassic

  1. The enigmatic whale: the North Atlantic humpback

    Directory of Open Access Journals (Sweden)

    Tim D Smith

    2009-09-01

    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.

  2. Fuzzy modelling of Atlantic salmon physical habitat

    Science.gov (United States)

    St-Hilaire, André; Mocq, Julien; Cunjak, Richard

    2015-04-01

    Fish habitat models typically attempt to quantify the amount of available river habitat for a given fish species for various flow and hydraulic conditions. To achieve this, information on the preferred range of values of key physical habitat variables (e.g. water level, velocity, substrate diameter) for the targeted fishs pecies need to be modelled. In this context, we developed several habitat suitability indices sets for three Atlantic salmon life stages (young-of-the-year (YOY), parr, spawning adults) with the help of fuzzy logic modeling. Using the knowledge of twenty-seven experts, from both sides of the Atlantic Ocean, we defined fuzzy sets of four variables (depth, substrate size, velocity and Habitat Suitability Index, or HSI) and associated fuzzy rules. When applied to the Romaine River (Canada), median curves of standardized Weighted Usable Area (WUA) were calculated and a confidence interval was obtained by bootstrap resampling. Despite the large range of WUA covered by the expert WUA curves, confidence intervals were relatively narrow: an average width of 0.095 (on a scale of 0 to 1) for spawning habitat, 0.155 for parr rearing habitat and 0.160 for YOY rearing habitat. When considering an environmental flow value corresponding to 90% of the maximum reached by WUA curve, results seem acceptable for the Romaine River. Generally, this proposed fuzzy logic method seems suitable to model habitat availability for the three life stages, while also providing an estimate of uncertainty in salmon preferences.

  3. Otolaryngology in Atlantic Canada: practitioners' perspectives.

    Science.gov (United States)

    Pelausa, E O

    1999-02-01

    A survey was conducted to assess practice conditions in Atlantic Canada for 1996. Otolaryngologists in Nova Scotia, New Brunswick, Prince Edward Island, and Newfoundland/Labrador with at least 1 year of practice experience in the area were canvassed regarding general work concerns, office and OR waiting lists, income, support services, job satisfaction, future plans and personal recommendations for improvement. Nineteen of 40 surveyed responded (47.5%). The results revealed that Atlantic Canadians had to wait considerably longer than average Canadians for ENT services. This was particularly true for Nova Scotians who had to wait often more than double the national average. Forty-seven and a half percent of practitioners were dissatisfied with the practice climate, with many merely trying to maintain status quo. Increasing government constraints and budget cuts have led to practice protectionism and the loss of collegiality. There is little optimism for the future, with 42% predicting continued deterioration in the next 5 years. As a result, up to 58% are considering relocating elsewhere. Despite diminishing returns, these specialists continue to provide the best possible care for their patient patients--hoping for a better tomorrow.

  4. Briefing : West Africa and its oil

    NARCIS (Netherlands)

    Ellis, S.

    2003-01-01

    The US war on terrorism and preparations for war against Iraq have enormously increased the strategic value of West African oil reserves. This comes at a time when there have been massive new discoveries in offshore waters. This article focuses on the increased US interests in West African oil. It

  5. Archives: West African Journal of Applied Ecology

    African Journals Online (AJOL)

    Items 1 - 30 of 30 ... Archives: West African Journal of Applied Ecology. Journal Home > Archives: West African Journal of Applied Ecology. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue ...

  6. West African Journal of Applied Ecology

    African Journals Online (AJOL)

    The focus of the West African Journal of Applied Ecologyis on ecology, agriculture and water pollution. It aims to serve as an avenue for lecturers and researchers in West Africa to publish their work. Other websites related to this journal are http://apps.ug.edu.gh/wajae/.

  7. 40 CFR 81.435 - West Virginia.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false West Virginia. 81.435 Section 81.435 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF... Visibility Is an Important Value § 81.435 West Virginia. Area name Acreage Public Law establishing Federal...

  8. Archives: West African Journal of Medicine

    African Journals Online (AJOL)

    Items 1 - 40 of 40 ... Archives: West African Journal of Medicine. Journal Home > Archives: West African Journal of Medicine. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives. 1 - 40 of ...

  9. West African Journal of Radiology: Submissions

    African Journals Online (AJOL)

    Author Guidelines. The West African Journal of Radiology (WAJR) is a publication and the official organ of the Association of Radiologists of West Africa. It is enlisted on AJOL (African Journals on-line). The Journal accepts for publication, original work in the science and technology of radiology, radiotherapy allied subjects, ...

  10. West Africanisms in Limonese Creole English.

    Science.gov (United States)

    Winkler, Elizabeth Grace; Obeng, Samuel Gyasi

    2000-01-01

    Discusses West Africanisms in Limonese Creole (LC), an English based creole language spoken in Costa Rica that shows substrate influence from the Kwa languages of West Africa, in particular from Akan (spoken in Ghana). Substrate influence is demonstrated through a comparison of LC and Akan morphophonology, morphosyntax, and lexicon. (Author/VWL)

  11. A founder mutation in LEPRE1 carried by 1.5% of West Africans and 0.4% of African Americans causes lethal recessive osteogenesis imperfecta.

    Science.gov (United States)

    Cabral, Wayne A; Barnes, Aileen M; Adeyemo, Adebowale; Cushing, Kelly; Chitayat, David; Porter, Forbes D; Panny, Susan R; Gulamali-Majid, Fizza; Tishkoff, Sarah A; Rebbeck, Timothy R; Gueye, Serigne M; Bailey-Wilson, Joan E; Brody, Lawrence C; Rotimi, Charles N; Marini, Joan C

    2012-05-01

    Deficiency of prolyl 3-hydroxylase 1, encoded by LEPRE1, causes recessive osteogenesis imperfecta (OI). We previously identified a LEPRE1 mutation exclusively in African Americans and contemporary West Africans. We hypothesized that this allele originated in West Africa and was introduced to the Americas with the Atlantic slave trade. We aimed to determine the frequency of carriers for this mutation among African Americans and West Africans, and the mutation origin and age. Genomic DNA was screened for the mutation using PCR and restriction digestion, and a custom TaqMan genomic single-nucleotide polymorphism assay. The mutation age was estimated using microsatellites and short tandem repeats spanning 4.2 Mb surrounding LEPRE1 in probands and carriers. Approximately 0.4% (95% confidence interval: 0.22-0.68%) of Mid-Atlantic African Americans carry this mutation, estimating recessive OI in 1/260,000 births in this population. In Nigeria and Ghana, 1.48% (95% confidence interval: 0.95-2.30%) of unrelated individuals are heterozygous carriers, predicting that 1/18,260 births will be affected with recessive OI, equal to the incidence of de novo dominant OI. The mutation was not detected in Africans from surrounding countries. All carriers shared a haplotype of 63-770 Kb, consistent with a single founder for this mutation. Using linkage disequilibrium analysis, the mutation was estimated to have originated between 650 and 900 years before present (1100-1350 CE). We identified a West African founder mutation for recessive OI in LEPRE1. Nearly 1.5% of Ghanians and Nigerians are carriers. The estimated age of this allele is consistent with introduction to North America via the Atlantic slave trade (1501-1867 CE).

  12. Human Rights in the West

    Directory of Open Access Journals (Sweden)

    Jorgen S. Nielsen

    1996-12-01

    Full Text Available One of the areas of conflict between Islam and the West in today’s world is the concern for human rights. This has sometimes been criticized in the Muslim world as a form of neo-imperialism. It is therefore necessary to understand the various dimensions of human rights, and the various phases through which this concern has grown. In the earliest form, it was an assertion of the rights of the landed aristocracy against those of the monarch. The French revolution, with its emphasis on "liberty, equality and fraternity," for all individuals, provided another dimension. There were many occasions on which individual and organized religion came into conflict during the Middle Ages. The experience of World War II, particularly the atrocities of the Nazis, led to the internationalization of individual rights.

  13. Westing in New Poems and three Persons

    Directory of Open Access Journals (Sweden)

    Ahmet Doğu

    2008-06-01

    Full Text Available Turkısh literature completes a long period effected by İslamic culture and cıvılızatıon in 19th century when it has tendency to west. Like empire, poets and writers also focus on west. They benefits from west in terms of literature and culture. In this way, they realize innovations in the field of literature and culture as beuracracy realizes in military, financial, administrative and maarif fields. This group of people who interest in the private journal sector in cultural field, French literature styles in literature and some sozcial topics evaluate “west issue” in the perspective of current political and social developments. In this context, Tevfik Fikret is in the favour of extention of borders related to westernism. He thinks of adopting west not only in terms of science, art and techniques but also in all social institutions. With the awakening of nation and nationalism, in the perod of National Literature emerging after II. Mesrutiyet besides the rejection of westernism (alafranga, westernism called civilization (muasırlaşma is also emphized. In this article west is evaluated from the point of view of Ziya Gökalp. According to Ziya Gökalp, west is a civilization circle which should be included in. Turkısh people should take their place in this circle by protecting national culture. Mehmet Akif, living in the same period and follwing Islamic style in his works, emphasizes that there should be limitations on the ınnovations taken from west. According to M. Akif, west can only be a model only in terms of science, art and technique. After 1912, M. Akif criticises west more severely

  14. Varied representation of the West Pacific pattern in multiple dynamical seasonal predictions of APCC-MME

    Science.gov (United States)

    Lee, Yun-Young

    2017-04-01

    West Pacific (WP) teleconnection pattern is one of the well-known primary modes of boreal winter low-frequency variability (LFV) resolved in 500 hPa geopotential height and its phase and amplitude strongly influence regional weather conditions including temperature and rainfall extremes [Baxter and Nigam, 2015; Hsu and Wallace, 1985; Linkin and Nigam, 2008; Mo and Livezey, 1986; Thompson and Wallace, 1998; Wallace and Gutzler, 1981]. This study primary aims to evaluate individual 11 GCMs seasonal hindcasts employed as members of multi-model ensemble (MME) produced in APEC Climate Center (APCC) in representing WP. For the extensive and comprehensive evaluation, this study applied seven verification metrics in three scopes: (a) temporal representation of observed indices, (b) spatial mode separation in the Northern Hemisphere (NH), and (c) regional mode isolated in the preset longitudinal domain. Verification results display quite large inter-model spread. Some models mimic observed index variability while others display large bias of index variability compared to climatology. Basic north-south dipole pattern is mostly well reproduced in both rotated and unrotated loading modes. However, each individual seasonal forecast model exhibits slightly different behavior (e.g. amplification/weakening, zonal and meridional shift, downstream extension and so forth) in representing spatial structure of WP. When taking all 7 metrics into account, one Europe (CMCC) model, one Oceania (POAMA) model and two North America (NASA and NCEP) models are classified as relatively good performers while PNU is classified as a matchless poor performer out of 11. Least WP representing skill of PNU is sort of consistent with the largest bias of NH total variability. This study further tries to examine winter mean biases of individual models and figure out how mean bias is linked to WP representation in model world. Model bias of winter climatology is investigated focusing on six large scale

  15. Frequency of Microplastics in Mesopelagic Fishes from the Northwest Atlantic

    Directory of Open Access Journals (Sweden)

    Alina M. Wieczorek

    2018-02-01

    Full Text Available Microplastics are a ubiquitous pollutant in our seas today and are known to have detrimental effects on a variety of organisms. Over the past decade numerous studies have documented microplastic ingestion by marine species with more recent investigations focussing on the secondary impacts of microplastic ingestion on ecosystem processes. However, few studies so far have examined microplastic ingestion by mesopelagic fish which are one of the most abundant pelagic groups in our oceans and through their vertical migrations are known to contribute significantly to the rapid transport of carbon and nutrients to the deep sea. Therefore, any ingestion of microplastics by mesopelagic fish may adversely affect this cycling and may aid in transport of microplastics from surface waters to the deep-sea benthos. In this study microplastics were extracted from mesopelagic fish under forensic conditions and analysed for polymer type utilising micro-Fourier Transform Infrared Spectroscopy (micro-FTIR analysis. Fish specimens were collected from depth (300–600 m in a warm-core eddy located in the Northwest Atlantic, 1,200 km due west of Newfoundland during April and May 2015. In total, 233 fish gut contents from seven different species of mesopelagic fish were examined. An alkaline dissolution of organic materials from extracted stomach contents was performed and the solution filtered over a 0.7 μm borosilicate filter. Filters were examined for microplastics and a subsample originating from 35 fish was further analysed for polymer type through micro-FTIR analysis. Seventy-three percent of all fish contained plastics in their gut contents with Gonostoma denudatum having the highest ingestion rate (100% followed by Serrivomer beanii (93% and Lampanyctus macdonaldi (75%. Overall, we found a much higher occurrence of microplastic fragments, mainly polyethylene fibres, in the gut contents of mesopelagic fish than previously reported. Stomach fullness, species and

  16. Basin-scale phenology and effects of climate variability on global timing of initial seaward migration of Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Otero, Jaime; L'Abée-Lund, Jan Henning; Castro-Santos, Ted; Leonardsson, Kjell; Storvik, Geir O; Jonsson, Bror; Dempson, Brian; Russell, Ian C; Jensen, Arne J; Baglinière, Jean-Luc; Dionne, Mélanie; Armstrong, John D; Romakkaniemi, Atso; Letcher, Benjamin H; Kocik, John F; Erkinaro, Jaakko; Poole, Russell; Rogan, Ger; Lundqvist, Hans; Maclean, Julian C; Jokikokko, Erkki; Arnekleiv, Jo Vegar; Kennedy, Richard J; Niemelä, Eero; Caballero, Pablo; Music, Paul A; Antonsson, Thorolfur; Gudjonsson, Sigurdur; Veselov, Alexey E; Lamberg, Anders; Groom, Steve; Taylor, Benjamin H; Taberner, Malcolm; Dillane, Mary; Arnason, Fridthjofur; Horton, Gregg; Hvidsten, Nils A; Jonsson, Ingi R; Jonsson, Nina; McKelvey, Simon; Naesje, Tor F; Skaala, Oystein; Smith, Gordon W; Saegrov, Harald; Stenseth, Nils C; Vøllestad, Leif Asbjørn

    2014-01-01

    Migrations between different habitats are key events in the lives of many organisms. Such movements involve annually recurring travel over long distances usually triggered by seasonal changes in the environment. Often, the migration is associated with travel to or from reproduction areas to regions of growth. Young anadromous Atlantic salmon (Salmo salar) emigrate from freshwater nursery areas during spring and early summer to feed and grow in the North Atlantic Ocean. The transition from the freshwater ('parr') stage to the migratory stage where they descend streams and enter salt water ('smolt') is characterized by morphological, physiological and behavioural changes where the timing of this parr-smolt transition is cued by photoperiod and water temperature. Environmental conditions in the freshwater habitat control the downstream migration and contribute to within- and among-river variation in migratory timing. Moreover, the timing of the freshwater emigration has likely evolved to meet environmental conditions in the ocean as these affect growth and survival of the post-smolts. Using generalized additive mixed-effects modelling, we analysed spatio-temporal variations in the dates of downstream smolt migration in 67 rivers throughout the North Atlantic during the last five decades and found that migrations were earlier in populations in the east than the west. After accounting for this spatial effect, the initiation of the downstream migration among rivers was positively associated with freshwater temperatures, up to about 10 °C and levelling off at higher values, and with sea-surface temperatures. Earlier migration occurred when river discharge levels were low but increasing. On average, the initiation of the smolt seaward migration has occurred 2.5 days earlier per decade throughout the basin of the North Atlantic. This shift in phenology matches changes in air, river, and ocean temperatures, suggesting that Atlantic salmon emigration is responding to the

  17. 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

    be measured directly but has to be estimated using the available data on light, temperature, pressure and salinity. The reconstructed locations based on advanced estimation techniques have been termed geolocations. Examples are discussed which illustrate the applicability of geolocations in individual path......-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...

  18. Spatiotemporal Analysis of the Ebola Hemorrhagic Fever in West Africa in 2014

    Science.gov (United States)

    Xu, M.; Cao, C. X.; Guo, H. F.

    2017-09-01

    Ebola hemorrhagic fever (EHF) is an acute hemorrhagic diseases caused by the Ebola virus, which is highly contagious. This paper aimed to explore the possible gathering area of EHF cases in West Africa in 2014, and identify endemic areas and their tendency by means of time-space analysis. We mapped distribution of EHF incidences and explored statistically significant space, time and space-time disease clusters. We utilized hotspot analysis to find the spatial clustering pattern on the basis of the actual outbreak cases. spatial-temporal cluster analysis is used to analyze the spatial or temporal distribution of agglomeration disease, examine whether its distribution is statistically significant. Local clusters were investigated using Kulldorff's scan statistic approach. The result reveals that the epidemic mainly gathered in the western part of Africa near north Atlantic with obvious regional distribution. For the current epidemic, we have found areas in high incidence of EVD by means of spatial cluster analysis.

  19. ATLANTIC BIRDS: a data set of bird species from the Brazilian Atlantic Forest.

    Science.gov (United States)

    Hasui, Érica; Metzger, Jean Paul; Pimentel, Rafael G; Silveira, Luís Fábio; Bovo, Alex A D A; Martensen, Alexandre C; Uezu, Alexandre; Regolin, André L; Bispo de Oliveira, Arthur Â; Gatto, Cassiano A F R; Duca, Charles; Andretti, Christian B; Banks-Leite, Cristina; Luz, Daniela; Mariz, Daniele; Alexandrino, Eduardo R; de Barros, Fabio M; Martello, Felipe; Pereira, Iolanda M D S; da Silva, José N; Ferraz, Katia M P M D B; Naka, Luciano N; Dos Anjos, Luiz; Efe, Márcio A; Pizo, Marco Aurélio; Pichorim, Mauro; Gonçalves, Maycon Sanyvan S; Cordeiro, Paulo Henrique Chaves; Dias, Rafael A; Muylaert, Renata D L; Rodrigues, Rodolpho C; da Costa, Thiago V V; Cavarzere, Vagner; Tonetti, Vinicius R; Silva, Wesley R; Jenkins, Clinton N; Galetti, Mauro; Ribeiro, Milton C

    2018-02-01

    South America holds 30% of the world's avifauna, with the Atlantic Forest representing one of the richest regions of the Neotropics. Here we have compiled a data set on Brazilian Atlantic Forest bird occurrence (150,423) and abundance samples (N = 832 bird species; 33,119 bird individuals) using multiple methods, including qualitative surveys, mist nets, point counts, and line transects). We used four main sources of data: museum collections, on-line databases, literature sources, and unpublished reports. The data set comprises 4,122 localities and data from 1815 to 2017. Most studies were conducted in the Florestas de Interior (1,510 localities) and Serra do Mar (1,280 localities) biogeographic sub-regions. Considering the three main quantitative methods (mist net, point count, and line transect), we compiled abundance data for 745 species in 576 communities. In the data set, the most frequent species were Basileuterus culicivorus, Cyclaris gujanensis, and Conophaga lineata. There were 71 singletons, such as Lipaugus conditus and Calyptura cristata. We suggest that this small number of records reinforces the critical situation of these taxa in the Atlantic Forest. The information provided in this data set can be used for macroecological studies and to foster conservation strategies in this biodiversity hotspot. No copyright restrictions are associated with the data set. Please cite this Data Paper if data are used in publications and teaching events. © 2017 by the Ecological Society of America.

  20. 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.

  1. North Atlantic Oscillation: Concept and an Application.

    Science.gov (United States)

    Lamb, Peter J.; Peppler, Randy A.

    1987-10-01

    An outline of the concept of the North Atlantic Oscillation (NAO), along with some of its history is presented. This is followed by a brief presentation of the results and implications of an encouraging new application of the NAO to a regional climate problem-the interannual variation of Moroccan winter-semester precipitation. That precipitation is shown to be inversely related to the concurrent state of the NAO, and the relationship is relatively strong by the standards of recent research into the mechanisms of tropical and subtropical precipitation fluctuations. It is suggested that the NAO is of particular significance for the important issue of the long-range prediction of Moroccan (and probably also Spanish, Portuguese, and Algerian) winter precipitation, and that further research on this subject is warranted. Several specific recommendations in the latter regard are made.

  2. Phylogeography of the West Indian manatee (Trichechus manatus): how many populations and how many taxa?

    Science.gov (United States)

    Garcia-Rodriguez, A I; Bowen, B W; Domning, D; Mignucci-Giannoni, A; Marmontel, M; Montoya-Ospina, A; Morales-Vela, B; Rudin, M; Bonde, R K; McGuire, P M

    1998-09-01

    To resolve the population genetic structure and phylogeography of the West Indian manatee (Trichechus manatus), mitochondrial (mt) DNA control region sequences were compared among eight locations across the western Atlantic region. Fifteen haplotypes were identified among 86 individuals from Florida, Puerto Rico, the Dominican Republic, Mexico, Columbia, Venezuela, Guyana and Brazil. Despite the manatee's ability to move thousands of kilometers along continental margins, strong population separations between most locations were demonstrated with significant haplotype frequency shifts. These findings are consistent with tagging studies which indicate that stretches of open water and unsuitable coastal habitats constitute substantial barriers to gene flow and colonization. Low levels of genetic diversity within Florida and Brazilian samples might be explained by recent colonization into high latitudes or bottleneck effects. Three distinctive mtDNA lineages were observed in an intraspecific phylogeny of T. manatus, corresponding approximately to: (i) Florida and the West Indies; (ii) the Gulf of Mexico to the Caribbean rivers of South America; and (iii) the northeast Atlantic coast of South America. These lineages, which are not concordant with previous subspecies designations, are separated by sequence divergence estimates of d = 0.04-0.07, approximately the same level of divergence observed between T. manatus and the Amazonian manatee (T. inunguis, n = 16). Three individuals from Guyana, identified as T. manatus, had mtDNA haplotypes which are affiliated with the endemic Amazon form T. inunguis. The three primary T. manatus lineages and the T. inunguis lineage may represent relatively deep phylogeographic partitions which have been bridged recently due to changes in habitat availability (after the Wisconsin glacial period, 10 000 B P), natural colonization, and human-mediated transplantation.

  3. Water type quantification in the Skagerrak, the Kattegat and off the Jutland west coast

    Directory of Open Access Journals (Sweden)

    Trond Kristiansen

    2015-04-01

    Full Text Available An extensive data series of salinity, nutrients and coloured dissolved organic material (CDOM was collected in the Skagerrak, the northern part of the Kattegat and off the Jutland west coast in April each year during the period 1996–2000, by the Institute of Marine Research in Norway. In this month, after the spring bloom, German Bight Water differs from its surrounding waters by a higher nitrate content and higher nitrate/phosphate and nitrate/silicate ratios. The spreading of this water type into the Skagerrak is of special interest with regard to toxic algal blooms. The quantification of the spatial distributions of the different water types required the development of a new algorithm for the area containing the Norwegian Coastal Current, while an earlier Danish algorithm was applied for the rest of the area. From the upper 50 m a total of 2227 observations of salinity and CDOM content have been used to calculate the mean concentration of water from the German Bight, the North Sea (Atlantic water, the Baltic Sea and Norwegian rivers. The Atlantic Water was the dominant water type, with a mean concentration of 79%, German Bight Water constituted 11%, Baltic Water 8%, and Norwegian River Water 2%. At the surface the mean percentages of these water types were found to be 68%, 15%, 15%, and 3%, respectively. Within the northern part of the Skagerrak, closer to the Norwegian coast, the surface waters were estimated to consist of 74% Atlantic Water, 20% Baltic Water, and 7% Norwegian River Water. The analysis indicates that the content of German Bight Water in this part is less than 5%.

  4. Atlantic continental margin of the United States

    Science.gov (United States)

    Grow, John A.; Sheridan, Robert E.; Palmer, A.R.

    1982-01-01

    The objective of this Decade of North American Geology (D-NAG) volume will be to focus on the Mesozoic and Cenozoic evolution of the U.S. Atlantic continental margin, including the onshore coastal plain, related onshore Triassic-Jurassic rift grabens, and the offshore basins and platforms. Following multiple compressional tectonic episodes between Africa and North America during the Paleozoic Era that formed the Appalachian Mountains, the Mesozoic and Cenozoic Eras were dominated by tensional tectonic processes that separated Africa and North America. Extensional rifting during Triassic and Early Jurassic times resulted in numerous tensional grabens both onshore and offshore, which filled with nonmarine continental red beds, lacustrine deposits, and volcanic flows and debris. The final stage of this breakup between Africa and North America occurred beneath the present outer continental shelf and continental slope during Early or Middle Jurassic time when sea-floor spreading began to form new oceanic crust and lithosophere between the two continents as they drifted apart. Postrift subsidence of the marginal basins continued in response to cooling of the lithosphere and sedimentary loading.Geophysical surveys and oil-exploration drilling along the U.S. Atlantic continental margin during the past 5 years are beginning to answer many questions concerning its deep structure and stratigraphy and how it evolved during the rifting and early sea-floor-spreading stages of the separation of this region from Africa. Earlier geophysical studies of the U.S. continental margin used marine refraction and submarine gravity measurements. Single-channel seismic-reflection, marine magnetic, aeromagnetic, and continuous gravity measurements became available during the 1960s.

  5. 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.

  6. 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.

  7. West German Jewry: Guilt, Power and Pluralism

    OpenAIRE

    Anthony d. Kauders

    2010-01-01

    The essay will address the history of West German Jewry using the concept of guilt as its guiding theme. Jews in West Germany had a bad conscience on account of living in the “land of the murderers.” This bad conscience not only distinguished them from other Jewish communities, it also explains much of what characterized West German Jewry from 1945 to 1989: its particular economic structure; its especially close ties to Israel; its preoccupation with democratization; its power arrangements; a...

  8. The transfer of reprocessing wastes from north-west Europe to the Arctic

    Science.gov (United States)

    Kershaw, Peter; Baxter, Amanda

    The discharge of radioactive waste, from nuclear fuel reprocessing facilities, into the coastal waters of north-west Europe has resulted in a significant increase in the inventories of a number of artificial radionuclides in the North Atlantic. Radiocaesium, 90Sr and 99Tc, which behave conservatively in seawater, have been used widely as tracers of water movement through the North Sea, Norwegian Coastal Current, Barents Sea, Greenland Sea, Fram Strait, Eurasian Basin, East Greenland Current and Denmark Strait overflow. These studies are summarised in the present paper. It has been estimated that 22% of the 137Cs Sellafield discharge has passed into the Barents Sea, en route to the Nansen Basin, via the Bjomoya-Fugloya Section, with another 13% passing through the Fram Strait. This amounts to 14 PBq 137Cs. Quantifying the influx of other radionuclides has been more problematic. The inflowing Atlantic water now appears to be diluting waters in the Arctic Basin, which were contaminated in the late 1970s and early 1980s as a result of the substantial decrease in the discharge of reprocessing wastes. Sellafield (U.K.) has dominated the supply of 134Cs, 137Cs, 90Sr, 99Tc and Pu, whereas La Hague (France) has contributed a larger proportion of 129I and 125Sb.

  9. Tiger sharks can connect equatorial habitats and fisheries across the Atlantic Ocean basin.

    Science.gov (United States)

    Afonso, André S; Garla, Ricardo; Hazin, Fábio H V

    2017-01-01

    Increasing our knowledge about the spatial ecology of apex predators and their interactions with diverse habitats and fisheries is necessary for understanding the trophic mechanisms that underlie several aspects of marine ecosystem dynamics and for guiding informed management policies. A preliminary assessment of tiger shark (Galeocerdo cuvier) population structure off the oceanic insular system of Fernando de Noronha (FEN) and the large-scale movements performed by this species in the equatorial Atlantic Ocean was conducted using longline and handline fishing gear and satellite telemetry. A total of 25 sharks measuring 175-372 cm in total length (TL) were sampled. Most sharks were likely immature females ranging between 200 and 260 cm TL, with few individuals shark size-distribution previously reported for coastal waters off the Brazilian mainland, where most individuals measured shark-1; SD = 65.6). These sharks exhibited a considerable variability in their horizontal movements, with three sharks showing a mostly resident behavior around FEN during the extent of the respective tracks, two sharks traveling west to the South American continent, and two sharks moving mostly along the middle of the oceanic basin, one of which ending up in the northern hemisphere. Moreover, one shark traveled east to the African continent, where it was eventually caught by fishers from Ivory Coast in less than 474 days at liberty. The present results suggest that young tiger sharks measuring sharks are able to connect marine trophic webs from the neritic provinces of the eastern and western margins of the Atlantic Ocean across the equatorial basin and that they may experience mortality induced by remote fisheries. All this information is extremely relevant for understanding the energetic balance of marine ecosystems as much as the exposure of this species to fishing pressure in this yet poorly-known region.

  10. Sources of iron and phosphate affect the distribution of diazotrophs in the North Atlantic

    Science.gov (United States)

    Ratten, Jenni-Marie; LaRoche, Julie; Desai, Dhwani K.; Shelley, Rachel U.; Landing, William M.; Boyle, Ed; Cutter, Gregory A.; Langlois, Rebecca J.

    2015-06-01

    Biological nitrogen fixation (BNF) supplies nutrient-depleted oceanic surface waters with new biologically available fixed nitrogen. Diazotrophs are the only organisms that can fix dinitrogen, but the factors controlling their distribution patterns in the ocean are not well understood. In this study, the relative abundances of eight diazotrophic phylotypes in the subtropical North Atlantic Ocean were determined by quantitative PCR (qPCR) of the nifH gene using TaqMan probes. A total of 152 samples were collected at 27 stations during two GEOTRACES cruises; Lisbon, Portugal to Mindelo, Cape Verde Islands (USGT10) and Woods Hole, MA, USA via the Bermuda Time Series (BATS) to Praia, Cape Verde Islands (USGT11). Seven of the eight diazotrophic phylotypes tested were detected. These included free-living and symbiotic cyanobacteria (unicellular groups (UCYN) A, B and C, Trichodesmium, the diatom-associated cyanobacteria Rhizoselinia-Richelia and Hemiaulus-Richelia) and a γ-proteobacterium (Gamma A, AY896371). The nifH gene abundances were analyzed in the context of a large set of hydrographic parameters, macronutrient and trace metal concentrations measured in parallel with DNA samples using the PRIMER-E software. The environmental variables that most influenced the abundances and distribution of the diazotrophic phylotypes were determined. We observed a geographic segregation of diazotrophic phylotypes between east and west, with UCYN A, UCYN B and UCYN C and the Rhizosolenia-Richelia symbiont associated with the eastern North Atlantic (east of 40°W), and Trichodesmium and Gamma A detected across the basin. Hemiaulus-Richelia symbionts were primarily found in temperate waters near the North American coast. The highest diazotrophic phylotype abundance and diversity were associated with temperatures greater than 22 °C in the surface mixed layer, a high supply of iron from North African aeolian mineral dust deposition and from remineralized nutrients upwelled at the

  11. Influence of particle composition on thorium cycling along the U.S. GEOTRACES North Atlantic Section

    Science.gov (United States)

    Lerner, Paul; Marchal, Olivier; Lam, Phoebe

    2017-04-01

    Our current knowledge about the behaviour of particle-reactive substances in the ocean stems largely from measurements of thorium radio-isotopes (Th-228, Th-230, Th-234) on seawater samples. The oceanic Th database has increased dramatically over the recent years, thanks in particular to the GEOTRACES program, an international study of the marine biogeochemical cycles of trace elements and their isotopes. Here we present an analysis of data collected at several stations of the U.S. GEOTRACES North Atlantic section (section GA03). Data originating from eleven stations situated west and east of the Middle-Atlantic Ridge are analyzed. First, at each station, the rate parameters of a single-particle class model of Th and particle cycling in the ocean water column are estimated from a least-squares fit to an eclectic data set, including (i) measurements of Th-228, Th-230, Th-234 activities in different size fractions, (ii) measurements of particle concentration, and (iii) measurements, or observational estimates, of the activities of the radio-active parents Ra-228, U-234, and U-238. Among our most salient results is a significant decrease in the apparent rate constant of Th adsorption (k1) with depth, with maxima in the meso-pelagic zone (ca. 100 - 1000 m) and minima below, at most stations. Second, we explore whether our k1 estimates can be related to changes in particle composition, both along the water column and laterally along GA03. We apply (i) multiple linear regression to quantify the amount of variance in k1 that can be explained by linear regression against particle composition data, and (ii) relative importance analysis to determine the relative contribution of different particulate phases to the explained variance in k1. Finally, the implications of our results for the interpretation of field Th isotope data and for the description of particle scavenging in ocean-biogeochemistry models are clarified.

  12. IAU South West Asian ROAD

    Science.gov (United States)

    Mickaelian, Areg; Azatyan, Naira; Farmanyan, Sona; Mikayelyan, Gor

    2016-10-01

    Armenia is hosting the IAU South West Asian (SWA) Regional Office of Astronomy for Development (ROAD). It is a county of ancient astronomy and is also rich in modern astronomical facilities and infrastructures, hence may successfully serve as a regional center for various activities. Byurakan Astrophysical Observatory (BAO) has 2.6m and 1m Schmidt, as well as a number of smaller telescopes that are an observational basis for joint projects and collaborations. Armenian Virtual Observatory (ArVO) is hosting astronomical databases, such as the Digitized First Byurakan Survey (DFBS) and may also serve as a basis for development of VO structures in this region. Recently we have conducted a number of new activities; a meeting on ``Relation of Astronomy to other Sciences, Culture and Society" (RASCS) was organized by BAO and Armenian Astronomical Society (ArAS) in Oct 2014 in Byurakan. Activities related to Archaeoastronomy and Astronomy in Culture (AAC) were initiated as well. Discussions on future Armenian-Iranian collaboration in astronomy were carried out, including an Armenian-Iranian Astronomical Workshop held in Oct 2015 in Byurakan. Similar workshops have been carried out between BAO and Abastumani Astronomical Observatory (AbAO, Georgia) since 1974.

  13. West Nile Virus Drug Discovery

    Directory of Open Access Journals (Sweden)

    Siew Pheng Lim

    2013-12-01

    Full Text Available The outbreak of West Nile virus (WNV in 1999 in the USA, and its continued spread throughout the Americas, parts of Europe, the Middle East and Africa, underscored the need for WNV antiviral development. Here, we review the current status of WNV drug discovery. A number of approaches have been used to search for inhibitors of WNV, including viral infection-based screening, enzyme-based screening, structure-based virtual screening, structure-based rationale design, and antibody-based therapy. These efforts have yielded inhibitors of viral or cellular factors that are critical for viral replication. For small molecule inhibitors, no promising preclinical candidate has been developed; most of the inhibitors could not even be advanced to the stage of hit-to-lead optimization due to their poor drug-like properties. However, several inhibitors developed for related members of the family Flaviviridae, such as dengue virus and hepatitis C virus, exhibited cross-inhibition of WNV, suggesting the possibility to re-purpose these antivirals for WNV treatment. Most promisingly, therapeutic antibodies have shown excellent efficacy in mouse model; one of such antibodies has been advanced into clinical trial. The knowledge accumulated during the past fifteen years has provided better rationale for the ongoing WNV and other flavivirus antiviral development.

  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 Oceanographic...

  15. 75 FR 28783 - South Atlantic Fishery Management Council; Public Meetings

    Science.gov (United States)

    2010-05-24

    ...: The meeting will be held at the Renaissance Orlando Airport Hotel, 5445 Forbes Place, Orlando, FL... Atlantic Fishery Management Council; Public Meetings AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce. ACTION: Notice of public meetings...

  16. Romania's Entrance into the North Atlantic Treaty Organization

    National Research Council Canada - National Science Library

    Pelesteanu, George M

    2006-01-01

    ... of the Euro-Atlantic area. Initiated in response to the new security architecture, the 1995 Study on NATO Enlargement established the principles and conditions to be accomplished by candidate states in order to become a full...

  17. Return of naturally sourced Pb to Atlantic surface waters

    NARCIS (Netherlands)

    Bridgestock, L.; van de Flierdt, T.; Rehkämper, M.; Paul, P.; Middag, R.; Milne, A.; Lohan, M.C.; Baker, A.; Chance, R.; Khondoker, R.; Strekopytov, S.; Humphreys-Williams, E.; Achterberg, E.P.; Rijkenberg, M.J.A.; Gerringa, L.J.A.; De Baar, H.J.W.

    2016-01-01

    Anthropogenic emissions completely overwhelmed natural marine lead (Pb) sources duringthe past century, predominantly due to leaded petrol usage. Here, based on Pb isotopemeasurements, we reassess the importance of natural and anthropogenic Pb sources to thetropical North Atlantic following the

  18. ON THE INFLUENCE OF GLOBAL WARMING ON ATLANTIC HURRICANE FREQUENCY

    Directory of Open Access Journals (Sweden)

    S. R. Hosseini

    2018-04-01

    Full Text Available In this paper, the possible connection between the frequency of Atlantic hurricanes to the climate change, mainly the variation in the Atlantic Ocean surface temperature has been investigated. The correlation between the observed hurricane frequency for different categories of hurricane’s intensity and Sea Surface Temperature (SST has been examined over the Atlantic Tropical Cyclogenesis Regions (ACR. The results suggest that in general, the frequency of hurricanes have a high correlation with SST. In particular, the frequency of extreme hurricanes with Category 5 intensity has the highest correlation coefficient (R = 0.82. In overall, the analyses in this work demonstrates the influence of the climate change condition on the Atlantic hurricanes and suggest a strong correlation between the frequency of extreme hurricanes and SST in the ACR.

  19. Fishermen's Energy Atlantic City Wind Farm

    Energy Technology Data Exchange (ETDEWEB)

    Wissemann, Chris [Fishermen' s Atlantic City Windfarm, LLC, Atlantic City, NJ (United States)

    2017-05-04

    Fishermen's Energy Atlantic City Wind Farm final report under US DOE Advanced Technology Demonstration project documents achievements developing a demonstration scale offshore wind project off the coast of New Jersey.

  20. 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...

  1. 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...

  2. 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...

  3. Photographic atlas of fish otoliths of the Northwest Atlantic Ocean

    National Research Council Canada - National Science Library

    Campana, Steven E

    2004-01-01

    This photographic atlas presents light and (or) scanning electron micrographs of 580 pairs of sagittal otoliths representing 288 species, 97 families, and 27 orders of fish from the northwest Atlantic...

  4. Structure and Evolution of Thermohaline Staircases in Tropical North Atlantic

    National Research Council Canada - National Science Library

    Wall, Steven

    2007-01-01

    .... Salt finger convection is generally observed in mid-latitude regions, particularly in the Atlantic Ocean and Mediterranean Sea, between the hase of the mixed layer and the top of the intermediate water...

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

    DEFF Research Database (Denmark)

    Bailey, J. C.; Gwozdz, R.

    1978-01-01

    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......, 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...... 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....

  6. New evidence for a South Atlantic stock of humpback whales ...

    African Journals Online (AJOL)

    New evidence for a South Atlantic stock of humpback whales wintering on the Northwest African continental shelf. Koen Van Waerebeek, Abdoulaye Djiba, Jens-Otto Krakstad, Abdellahi Samba Ould Bilal, Idrissa L. Bamy, Amadeu Almeida, Ebou Mass Mbye ...

  7. RESISTANCE EVALUATION ON POPULATIONS OF CROSSES BETWEEN TRANSGENIC POTATO KATAHDIN RB AND NON-TRANSGENIC ATLANTIC AND GRANOLA TO LATE BLIGHT (Phytophthora infestans IN CONFINED FIELD TRIAL

    Directory of Open Access Journals (Sweden)

    Alberta Dinar Ambarwati

    2011-04-01

    Full Text Available Late blight resistance gene (RB gene isolated from Solanum bulbocastanum, is a broad resistance gene against all races of Phytophthora infestans. The gene was transformed into Katah-din event SP904 and SP951 using Agrobacterium tumefaciens and these transgenic plants have been crossed with susceptible potato cultivars Atlantic and Granola. Populations of the crosses have been molecularly characterized for the integration of the RB transgene. The study aimed to evaluate the resistance of the populations of crosses between transgenic Katahdin RB  and susceptible non-transgenic parents (Atlantic and Granola to late blight in a confined field trial at Pasir Sarongge, Cianjur, West Java. A total of 84 clones originated from four popula-tions were evaluated for resistance to late blight. These included 22 clones of Atlantic x transgenic Katahdin SP904, 16 clones of Atlantic x transgenic Katahdin SP951, 19 clones of Granola x transgenic Katahdin SP904, and 27 clones of Granola x transgenic Katahdin SP951. Observations of the late blight infection were conducted when late blight symptoms were detected, i.e. at 56, 60, 63, 70, and 77 days after planting (DAP. The result showed there were high variations in the resistance level of all the 84 clones tested. Clones of crosses between susceptible parents (Atlantic or Granola and resistant parents (transgenic Katahdin SP904 or Katahdin SP951 showed a similar pattern based on the area under disease progress curve (AUDPC value, i.e. 377.2 greater than the AUDPC of the resistant parents (180.1, but smaller than that of the susceptible parents (670.7. Observation at 77 DAP resulted four resistant potato clones having resistance score of 7.0-7.6, higher than the transgenic parents Katahdin SP904 (4.6 and Katahdin SP951 (6.8, i.e. clone B8 (Atlantic x transgenic Katahdin SP951 with resistance score of 7.6 and clones B26 (Atlantic x transgenic Katahdin SP951, C183 (Granola x transgenic Katahdin SP904, and D89

  8. Remotely forced variability in the tropical Atlantic Ocean

    Energy Technology Data Exchange (ETDEWEB)

    Huang, B. [Center for Ocean-Land-Atmosphere Studies, Institute of Global Environment and Society, 4041 Powder Mill Road, Calverton, Maryland 20705 (United States)

    2004-08-01

    An ensemble of eight hindcasts has been conducted using an ocean-atmosphere general circulation model fully coupled only within the Atlantic basin, with prescribed observational sea surface temperature (SST) for 1950-1998 in the global ocean outside the Atlantic basin. The purpose of these experiments is to understand the influence of the external SST anomalies on the interannual variability in the tropical Atlantic Ocean. Statistical methods, including empirical orthogonal function analysis with maximized signal-to-noise ratio, have been used to extract the remotely forced Atlantic signals from the ensemble of simulations. It is found that the leading external source on the interannual time scales is the El Nino/Southern Oscillation (ENSO) in the Pacific Ocean. The ENSO signal in the tropical Atlantic shows a distinct progression from season to season. During the boreal winter of a maturing El Nino event, the model shows a major warm center in the southern subtropical Atlantic together with warm anomalies in the northern subtropical Atlantic. The southern subtropical SST anomalies is caused by a weakening of the southeast trade winds, which are partly associated with the influence of an atmospheric wave train generated in the western Pacific Ocean and propagating into the Atlantic basin in the Southern Hemisphere during boreal fall. In the boreal spring, the northern tropical Atlantic Ocean is warmed up by a weakening of the northeast trade winds, which is also associated with a wave train generated in the central tropical Pacific during the winter season of an El Nino event. Apart from the atmospheric planetary waves, these SST anomalies are also related to the sea level pressure (SLP) increase in the eastern tropical Atlantic due to the global adjustment to the maturing El Nino in the tropical Pacific. The tropical SLP anomalies are further enhanced in boreal spring, which induce anomalous easterlies on and to the south of the equator and lead to a dynamical

  9. 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

  10. Upper Triassic mafic dykes of Lake Nyos, Cameroon (West Africa) I: K-Ar age evidence within the context of Cameroon Line magmatism, and the tectonic significance

    Science.gov (United States)

    Aka, Festus Tongwa; Hasegawa, Takeshi; Nche, Linus Anye; Asaah, Asobo Nkengmatia Elvis; Mimba, Mumbfu Ernestine; Teitchou, Isidore; Ngwa, Caroline; Miyabuchi, Yasuo; Kobayashi, Tetsuo; Kankeu, Boniface; Yokoyama, Tetsuya; Tanyileke, Gregory; Ohba, Takeshi; Hell, Joseph Victor; Kusakabe, Minoru

    2018-05-01

    The hydrodynamic fragmentation that formed Lake Nyos in northwest Cameroon did not only make it the most unpopular lake in the world from a gas disaster perspective, it also opened a rare and formidable window through which much of the geology of Cameroon can be studied in a single locality. The Cambrian quartz monzonite cliff excavated by the maar-forming explosion and exposed in its northeastern shore is intruded by mafic dykes, two of which we dated. Even though close to one another, the dykes are different in composition. The alkaline dyke yields a slightly older (Carnian) K-Ar fedspar age of 231.1 ± 4.8 Ma, while the sub alkaline dyke yields an age of 224.8 ± 4.7 Ma (Norian). Based on radioisotopic age data available over the last 48 years (347 data) for the Cameroon Line magmatism comprising eruptives and volcano-plutonic complexes, the Nyos dykes are way older than the Cameroon Line, and even pre-date the Lower Cretaceous initiation of west Gondwana fragmentation in Equatorial Atlantic domain. They would therefore not have been directly linked to the formation of the Cameroon Line. Alternatively, they might be associated with the development of intra-continental rift systems in West Central Africa that pre-dated west Gondwana breakup to form the Atlantic Ocean.

  11. Erosional history of the Appalachians as recordeed in detrital zircon fission-track ages and lithic detritus in Atlantic Coastal Plain sediments

    Science.gov (United States)

    Naeser, C.W.; Naeser, N.D.; Edwards, Lucy E.; Weems, Robert E.; Southworth, C. Scott; Newell, Wayne L.

    2016-01-01

    and Maryland, sands of Early Cretaceous through late early Oligocene age do not yield any old zircons comparable in age to the old zircons found in bedrock in the western Appalachians. Very old zircons yielding FT ages >800 Ma are only encountered in Coastal Plain sands of middle early Miocene and younger age.Miocene and younger fluvial-deltaic deposits associated with the major mid-Atlantic Coastal Plain rivers that now head in the western Appalachians (the Hudson, Delaware, Susquehanna, Potomac, James, and Roanoke) contain abundant clasts of fossiliferous chert and quartzite and other distinctive rock types derived from Paleozoic rocks of the western Appalachians. These distinctive clasts have not been reported in older Coastal Plain sediments.The ZFT and lithic detritus data indicate that the drainage divide for one or more east-flowing mid-Atlantic rivers migrated west into the western Appalachians, and the river(s) began transporting western Appalachian detritus to the Atlantic Coastal Plain, sometime between the late early Oligocene and middle early Miocene. By no later than late middle Miocene most if not all of the major rivers that now head west of the Blue Ridge were transporting western Appalachian detritus to the Coastal Plain. Prior to the drainage divide migrating into the western Appalachians, the ZFT data are consistent with the dominant source of Atlantic Coastal Plain sediments being detritus from the Piedmont and main part of the Blue Ridge, with possible input from distant volcanic sources.The ZFT data suggest that the rapid increase in the rate of siliciclastic sediment accumulation in middle Atlantic margin offshore basins that peaked in the middle Miocene and produced almost 30 percent of the total volume of post-rift siliciclastic sediments in the offshore basins began in the early Miocene when Atlantic river(s) gained access to the relatively easily eroded Paleozoic sedimentary rocks of the western Appalachians.

  12. Characteristics of genetic factors that influence gender in Atlantic salmon

    OpenAIRE

    Cheung, Cliff

    2011-01-01

    Very little is currently known about how gender is established in Atlantic salmon, and environmental and commercial matters have increased interest in the life history strategies of this ancient fish. It is necessary to assess the sex ratios in populations of Atlantic salmon both before they head out to oceanic feeding grounds and when they return to spawn, before we can begin to understand the mechanisms that govern gender in this species. Much of the challenge faced by those studying gender...

  13. Atlantic effects on recent decadal trends in global monsoon

    OpenAIRE

    KAMAE, Youichi; LI, Xichen; XIE, Shang-Ping; UEDA, Hiroaki

    2017-01-01

    Natural climate variability contributes to recent decadal climate trends. Specifically the trends during the satellite era since 1979 include Atlantic and Indian Ocean warming and Pacific cooling associated with phase shifts of the Atlantic Multidecadal Oscillation and the Pacific Decadal Oscillation, and enhanced global monsoon (GM) circulation and rainfall especially in the Northern Hemisphere. Here we evaluate effects of the oceanic changes on the global and regional monsoon trends by part...

  14. Karakterisasi Kentang Varietas Granola, Atlantic, Dan Balsa Dengan Metode UPOV

    OpenAIRE

    Kusmana, nFN; Sofiari, Eri

    2007-01-01

    Characterization was carried out in Indonesian Vegetable Reserach Institute (IVEGRI), Lembang. Twenty plants/plot and three replications for each variety were arranged in Randomized Block Design. The objective of the experiment was to compile characters of potato varieties Granola, Atlantic, and Balsa by implementing UPOV methods. The result shown in the form of table containing descriptions of 50 characters of Granola, Atlantic, and Balsa varieties.

  15. Structure and Evolution of Thermohaline Staircases in Tropical North Atlantic

    Science.gov (United States)

    2007-12-01

    series of mixed layers separated by sharp interfaces. The discovery of these ‘ thermohaline staircases’ by Tait and Howe (1968) further stimulated...EVOLUTION OF THERMOHALINE STAIRCASES IN TROPICAL NORTH ATLANTIC by Steven Wall December 2007 Thesis Advisor: Timour Radko Second Reader...DATES COVERED Master’s Thesis 4. TITLE AND SUBTITLE Structure and Evolution of Thermohaline Staircases in Tropical North Atlantic 6. AUTHOR(S

  16. Legume Diversity Patterns in West Central Africa

    NARCIS (Netherlands)

    Estrella, de la M.; Mateo, M.A.; Wieringa, J.J.; Mackinder, B.; Munoz, J.

    2012-01-01

    Objectives - Species Distribution Models (SDMs) are used to produce predictions of potential Leguminosae diversity in West Central Africa. Those predictions are evaluated subsequently using expert opinion. The established methodology of combining all SDMs is refined to assess species diversity

  17. 2012 OLC Lidar DEM: West Metro, Oregon

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — WSI has collected Light Detection and Ranging (LiDAR) data of the Oregon West Metro Study Area for the Oregon Department of Geology and Mineral Industries (DOGAMI)....

  18. NNDSS - Table II. West Nile virus disease

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. West Nile virus disease - 2017. In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during the preceding year),...

  19. NNDSS - Table II. West Nile to Zika

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. West Nile to Zika - 2018. In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during the preceding year), and...

  20. West Bank Gaza Geo-MIS System

    Data.gov (United States)

    US Agency for International Development — The Geo-MIS System is USAID/West Bank and Gaza's primary system for capturing and managing projectrelated information. Its purpose is to assist USAID and its...

  1. NNDSS - Table II. West Nile virus disease

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. West Nile virus disease - 2016. In this Table, provisional* cases of selected† notifiable diseases (≥1,000 cases reported during the preceding...

  2. NNDSS - Table II. West Nile to Zika

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. West Nile to Zika - 2018. In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during the preceding year), and...

  3. NNDSS - Table II. West Nile virus disease

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. West Nile virus disease - 2015.In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during the preceding year),...

  4. Eighteenth annual West Coast theoretical chemistry conference

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-05-01

    Abstracts are presented from the eighteenth annual west coast theoretical chemistry conference. Topics include molecular simulations; quasiclassical simulations of reactions; photodissociation reactions; molecular dynamics;interface studies; electronic structure; and semiclassical methods of reactive systems.

  5. 2012 OLC Lidar: West Metro, Oregon

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — WSI has collected Light Detection and Ranging (LiDAR) data of the Oregon West Metro Study Area for the Oregon Department of Geology and Mineral Industries (DOGAMI)....

  6. West Coast Rockfish Conservation Areas, 2015

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data delineate Rockfish Conservation Areas (RCA) off the West Coast of the United States for 2015. There are three types of areas closures depicted in this...

  7. NNDSS - Table II. West Nile virus disease

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. West Nile virus disease - 2017. In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during the preceding...

  8. Future markers of the West Greenlandic

    DEFF Research Database (Denmark)

    Trondhjem, Naja Blytmann

    2010-01-01

    Abstract West Greenlandic, a polysynthetic language, belongs to Inuit languages. In Inuktitut (Canada) and West Greenlandic (Inuit languages) tense is marked by optional tense suffixes and in both languages the temporal systems are based on a future/ non-future opposition. In Inuktitut the tense...... suffixes have developed a complicated remoteness system. In West Greenlandic the future tense suffixes have a distinction between vague and inevitable future, and the past time suffixes have developed different perfect meanings. In Iñupiaq (Alaska), the temporal system is based on an opposition between...... past, present and future, where tense is marked in the flectional morpheme, but only in the indicative mood. There are only a few tense suffixes. The meanings of these tense suffixes are the same as those of the West Greenlandic tense suffixes. My current work is a typological investigation about...

  9. Hydrography and circulation west of Sardinia in June 2014

    Science.gov (United States)

    Knoll, Michaela; Borrione, Ines; Fiekas, Heinz-Volker; Funk, Andreas; Hemming, Michael P.; Kaiser, Jan; Onken, Reiner; Queste, Bastien; Russo, Aniello

    2017-11-01

    In the frame of the REP14-MED sea trial in June 2014, the hydrography and circulation west of Sardinia, observed by means of gliders, shipborne CTD (conductivity, temperature, depth) instruments, towed devices, and vessel-mounted ADCPs (acoustic doppler current profilers), are presented and compared with previous knowledge. So far, the circulation is not well-known in this area, and the hydrography is subject to long-term changes. Potential temperature, salinity, and potential density ranges as well as core values of the observed water masses were determined. Modified Atlantic Water (MAW), with potential density anomalies below 28.72 kg m-3, showed a salinity minimum of 37.93 at 50 dbar. Levantine Intermediate Water (LIW), with a salinity maximum of about 38.70 at 400 dbar, was observed within a range of 28.72ADCP measurements. Within the MAW, northward currents were observed over the shelf and offshore, while a southward transport of about 1.5 Sv occurred over the slope. A net northward transport of 0.38 Sv across the southern transect decreased to zero in the north. Within the LIW, northward transports of 0.6 Sv across the southern transects were mainly observed offshore, and decreased to 0.3 Sv in the north where they were primarily located over the slope. This presentation of the REP14-MED observations helps to further understand the long-term evolution of hydrography and circulation in the Western Mediterranean, where considerable changes occurred after the Eastern Mediterranean Transient and the Western Mediterranean Transition.

  10. Helminth parasites of the oceanic horse mackerel Trachurus picturatus Bowdich 1825 (Pisces: Carangidae) from Madeira Island, Atlantic Ocean, Portugal.

    Science.gov (United States)

    Costa, G; Melo-Moreira, E; Pinheiro de Carvalho, M A A

    2012-09-01

    The helminth parasite fauna of the oceanic horse mackerel Trachurus picturatus Bowdich 1825, caught off the Madeira Islands was composed of six different taxa. Prevalence and abundance of larval Anisakis sp. (Nematoda: Anisakidae) and Nybelinia lingualis (Trypanorhyncha: Tentaculariidae), the most common parasite taxa, were 24.3%, 0.9 and 37.9%, 0.7, respectively. Bolbosoma vasculosum (Acanthocephala: Polymorphidae) and the monogeneans Heteraxinoides atlanticus (Monogenea: Heteraxinidae) and Pseudaxine trachuri (Monogenea: Gastrocotylidae) were comparatively rare. The depauperate helminth fauna of the oceanic horse mackerel at Madeira compared to other geographical regions of the north-eastern Atlantic, namely the Azores banks and the West African coast, may be attributed to the paucity of nutrients off oceanic islands and to a low density of the fish population.

  11. Microbial keratitis in West and East Malaysia

    OpenAIRE

    Vanitha Ratnalingam; Thiageswari Umapathy; Kala Sumugam; Hanida Hanafi; Shamala Retnasabapathy

    2017-01-01

    AIM: To evaluate the epidemiological and etiological factors of microbial keratitis seen in tertiary hospitals in West and East Malaysia.METHODS: A total of 207 patients were enrolled. Patients referred for microbial keratitis to Sungai Buloh Hospital and Kuala Lumpur Hospital in West Malaysia and Queen Elizabeth Hospital and Kuching General Hospital in East Malaysia were recruited. Risk factors were documented. Corneal scrapings for microscopy and culture were performed.RESULTS: The most com...

  12. Wildlife resources of the West African savanna

    OpenAIRE

    Bie, de, S.

    1991-01-01

    The wild fauna in Africa is a renewable resource and its overexploitation has led to the depletion of animal populations. This thesis focusses on the ecological characterization of the ungulate community of the West African savanna, with special reference to the Biosphere Reserve 'Boucle du Baoulé' in Mali, and makes a contribution to the ecological knowledge required for the conservation and management of West African savanna ecosystems.

    Part I contains background informatio...

  13. Congenital defects of atlantal arch. A report of eight cases

    International Nuclear Information System (INIS)

    Tajima, Yosuke; Saeki, Naokatsu; Sugiyama, Ken; Masuda, Kosuke; Ishige, Satoshi; Yamauchi, Toshihiro; Miyata, Akihiro; Nakamura, Hiroshi; Kobayashi, Shigeki

    2010-01-01

    Atlantal arch defects are rare. The purpose of this paper is to investigate the incidence and clinical implications of these, using Cervical CT with traumatic patients. A retrospective review of 1,534 cervical spine computed tomography (CT) scans was performed to identify patients with atlantal arch defects. Posterior arch defects of the atlas were grouped in accordance with the classification of Currarino et al. Posterior arch defects were found in 7 (7/1534, 0.44%) and anterior arch defects were found in 2 (2/1534, 0.13%) of the 1,534 patients. The type A posterior arch defect was found in 5 patients and the type B posterior arch defect was found in 2 patients. No type C, D, or E defects were observed. One patient with a type B posterior arch defect had an anterior atlantal-arch midline cleft. Associated cervical spine anomaly was not observed in our cases. None of the reviewed patients had neurological deficits because of atlantal arch defects. Most congenital anomalies of the atlantal arch are found incidentally during investigation of neck mass, neck pain, radiculopathy, and after trauma. Almost cases of atlantal arch defects are not need to operate. But it is important to note some cases require surgical treatment. (author)

  14. Atlantic effects on recent decadal trends in global monsoon

    Science.gov (United States)

    Kamae, Youichi; Li, Xichen; Xie, Shang-Ping; Ueda, Hiroaki

    2017-11-01

    Natural climate variability contributes to recent decadal climate trends. Specifically the trends during the satellite era since 1979 include Atlantic and Indian Ocean warming and Pacific cooling associated with phase shifts of the Atlantic Multidecadal Oscillation and the Pacific Decadal Oscillation, and enhanced global monsoon (GM) circulation and rainfall especially in the Northern Hemisphere. Here we evaluate effects of the oceanic changes on the global and regional monsoon trends by partial ocean temperature restoring experiments in a coupled atmosphere-ocean general circulation model. Via trans-basin atmosphere-ocean teleconnections, the Atlantic warming drives a global pattern of sea surface temperature change that resembles observations, giving rise to the enhanced GM. The tropical Atlantic warming and the resultant Indian Ocean warming favor subtropical deep-tropospheric warming in both hemispheres, resulting in the enhanced monsoon circulations and precipitation over North America, South America and North Africa. The extratropical North Atlantic warming makes an additional contribution to the monsoon enhancement via Eurasian continent warming and resultant land-sea thermal gradient over Asia. The results of this study suggest that the Atlantic multidecadal variability can explain a substantial part of global climate variability including the recent decadal trends of GM.

  15. Impact of the Atlantic on multidecadal tropical Pacific Variability

    Science.gov (United States)

    Levine, A. F. Z.; McPhaden, M. J.; Frierson, D. M.

    2017-12-01

    Multidecadal shifts in ENSO variability have been observed, but it is unclear if this variability is just a random variation in the ENSO cycle or whether it is forced by other modes of climate variability. Recent studies have suggested that the observed mean state differences in the tropical Pacific from the first decade and a half of the new millennium were driven by changes in the Atlantic SSTs. Here, we will show that the impact of Atlantic SST forcing on the tropical Pacific mean state are expressed as asymmetric changes to the annual cycle. The asymmetric changes in the tropical Pacific annual cycle creates a distinct signature in the relationship between the ENSO and the tropical Pacific annual cycle that we observe in the multidecadal ENSO variability in reanalysis and proxy records and that this variability follows the Atlantic Multidecadal Variability. We further find that there are concurrent changes in the location of the tropical Pacific ITCZ on multidecadal timescales. The shifts in location of the ITCZ in response to a warmer north Atlantic are consistent with the predictions of an ITCZ shift forced by an enhanced interhemispheric energy gradient. Targeted coupled model experiments are then used to confirm the impact of Atlantic Multidecadal Variability on the tropical Pacific multidecadal variability and explore the impact of SST changes across different regions of the Atlantic.

  16. The Rockall Trough, NE Atlantic: An Extinct Young Ocean Basin or a Failed Breakup Basin?

    Science.gov (United States)

    Roberts, Alan; Kusznir, Nick; Alvey, Andy

    2017-04-01

    We investigate the crustal structure and composition of the Rockall Trough which is located in the NE Atlantic to the west of Ireland and the UK. The Rockall Trough is a large extensional basin formed in the Early Cretaceous and has dimensions of approximately 250 km in width and 1000 km in length. It is one of several basins formed during the complex Mesozoic northward propagation of rifting, continental breakup and sea-floor spreading initiation of the North Atlantic; other adjacent basins formed at this time include the Porcupine Trough to its east and the East and West Orphan Basins on the Canadian conjugate margin. To investigate the crustal structure of the Rockall Trough we have used three independent analyses of available 2D and 3D data: 1. 3D gravity inversion, using public-domain gravity and sediment-thickness information, has produced maps of (i) depth to Moho, (ii) crustal thickness (figure 1) and (iii) stretching/thinning factor across both margins. 2. Gravity inversion as above, but using public-domain gravity data combined with new proprietary 2D sediment-thickness information, has produced a series of cross-sections which show (i) depth to Moho, (ii) crustal thickness and (iii) stretching/thinning factor across both margins 3. Geodynamic modelling, comprising 2D flexural backstripping and forward modelling, has been used to produce (i) estimates of stretching/thinning factor, (ii) whole-crustal cross-sections and (iii) predictions of palaeobathymetry through time along a series of project-specific transects. Our analysis of the Rockall Trough shows a rapid shallowing of crustal basement thicknesses on the flanks of the basin with central values of crustal thickness typically 8-10 km consistent with previously published seismic estimates. An important question is whether this thin crust is hyper-extended continental crust or proto-oceanic crust. Locally isolated patches of crustal thicknesses as low as 3km are observed which are consistent with the

  17. Tiger sharks can connect equatorial habitats and fisheries across the Atlantic Ocean basin.

    Directory of Open Access Journals (Sweden)

    André S Afonso

    Full Text Available Increasing our knowledge about the spatial ecology of apex predators and their interactions with diverse habitats and fisheries is necessary for understanding the trophic mechanisms that underlie several aspects of marine ecosystem dynamics and for guiding informed management policies. A preliminary assessment of tiger shark (Galeocerdo cuvier population structure off the oceanic insular system of Fernando de Noronha (FEN and the large-scale movements performed by this species in the equatorial Atlantic Ocean was conducted using longline and handline fishing gear and satellite telemetry. A total of 25 sharks measuring 175-372 cm in total length (TL were sampled. Most sharks were likely immature females ranging between 200 and 260 cm TL, with few individuals < 200 cm TL being caught. This contrasts greatly with the tiger shark size-distribution previously reported for coastal waters off the Brazilian mainland, where most individuals measured < 200 cm TL. Also, the movements of 8 individuals measuring 202-310 cm TL were assessed with satellite transmitters for a combined total of 757 days (mean = 94.6 days∙shark-1; SD = 65.6. These sharks exhibited a considerable variability in their horizontal movements, with three sharks showing a mostly resident behavior around FEN during the extent of the respective tracks, two sharks traveling west to the South American continent, and two sharks moving mostly along the middle of the oceanic basin, one of which ending up in the northern hemisphere. Moreover, one shark traveled east to the African continent, where it was eventually caught by fishers from Ivory Coast in less than 474 days at liberty. The present results suggest that young tiger sharks measuring < 200 cm TL make little use of insular oceanic habitats from the western South Atlantic Ocean, which agrees with a previously-hypothesized ontogenetic habitat shift from coastal to oceanic habitats experienced by juveniles of this species in this region

  18. Contourite drift off Madeira Island (Northeast Atlantic) and implications to Cenozoic bottom-current circulation

    Science.gov (United States)

    Roque, Cristina; Hernández-Molina, F. Javier; Madureira, Pedro; Quartau, Rui; Magalhães, Vitor; Carrara, Gabriela; Santos de Campos, Aldino; Brandão, Filipe; Tomás Vázquez, Juan; Somoza, Luis

    2017-04-01

    During the last decades several works have been carried out on the morphosedimentary processes driven by bottom-currents in several continental margins and abyssal plains worldwide. However these processes still remain poorly understood on deep-water settings and particularly around oceanic islands. This study is focused on the offshore of Madeira Island (Portugal), which is located in the Northeast Atlantic at about 700 km west of NW Africa. The interpretation of a newly acquired dataset, composed of multibeam bathymetry, Parasound echosounder profiles and multichannel seismic reflection profiles, allowed to identify a giant (about 385 km long and over than 175 km wide) plastered contourite drift, called the "Madeira Drift", developing along the lower slope of the Madeira plateau. It formed on top of a major erosional unconformity that truncates the underlying pelagic deposits, which drape over faulted blocks of Cretaceous oceanic crust. The Madeira Drift is composed of three main regional seismic units showing a predominant aggradational stacking pattern, without evidence of major lateral migration thought time. Its internal configuration indicates that it was build-up by a northwards flowing deep bottom current. These characteristics suggests that an almost persistent and stable water mass has been responsible for its edification trough time. While the precise age of this contourite drift is undetermined, some chronostratigraphic constraints can be determined based upon published works regarding seafloor magnetic anomalies (e.g. Bird et al., 2007), DSDP Site 136drilling data (Hayes et al., 1978). Attending to this, we propose that the possible onset of Madeira Drift must have occurred after Late Cretaceous, within the tertiary period, and quite probably in the Late Eocene / Eocene-Oligocene transition. Based on them is commonly accepted that an enhanced proto-Antarctic Bottom Water (AABW) started to circulate at that time we considered this water mass as the

  19. Characterization of "dead-zone" eddies in the eastern tropical North Atlantic

    Science.gov (United States)

    Schütte, Florian; Karstensen, Johannes; Krahmann, Gerd; Hauss, Helena; Fiedler, Björn; Brandt, Peter; Visbeck, Martin; Körtzinger, Arne

    2016-10-01

    Localized open-ocean low-oxygen "dead zones" in the eastern tropical North Atlantic are recently discovered ocean features that can develop in dynamically isolated water masses within cyclonic eddies (CE) and anticyclonic mode-water eddies (ACME). Analysis of a comprehensive oxygen dataset obtained from gliders, moorings, research vessels and Argo floats reveals that "dead-zone" eddies are found in surprisingly high numbers and in a large area from about 4 to 22° N, from the shelf at the eastern boundary to 38° W. In total, 173 profiles with oxygen concentrations below the minimum background concentration of 40 µmol kg-1 could be associated with 27 independent eddies (10 CEs; 17 ACMEs) over a period of 10 years. Lowest oxygen concentrations in CEs are less than 10 µmol kg-1 while in ACMEs even suboxic (ocean. Here water mass properties and satellite eddy tracking both point to an eddy generation near the eastern boundary. In contrast, the oxygen-depleted eddies south of 12° N carry weak hydrographic anomalies in their cores and seem to be generated in the open ocean away from the boundary. In both regions a decrease in oxygen from east to west is identified supporting the en-route creation of the low-oxygen core through a combination of high productivity in the eddy surface waters and an isolation of the eddy cores with respect to lateral oxygen supply. Indeed, eddies of both types feature a cold sea surface temperature anomaly and enhanced chlorophyll concentrations in their center. The low-oxygen core depth in the eddies aligns with the depth of the shallow oxygen minimum zone of the eastern tropical North Atlantic. Averaged over the whole area an oxygen reduction of 7 µmol kg-1 in the depth range of 50 to 150 m (peak reduction is 16 µmol kg-1 at 100 m depth) can be associated with the dispersion of the eddies. Thus the locally increased oxygen consumption within the eddy cores enhances the total oxygen consumption in the open eastern tropical North

  20. 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...

  1. Current velocity and hydrographic observations in the Southwestern North Atlantic Ocean: Subtropical Atlantic Climate Studies (STACS), 1989 (NODC Accession 9100033)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The primary objective of the STACS program are to increase our understanding of the dynamics of the North Atlantic circulation and the role of the ocean circulation...

  2. 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 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.

  3. West Nile virus: North American experience

    Science.gov (United States)

    Hofmeister, Erik K.

    2011-01-01

    West Nile virus, a mosquito-vectored flavivirus of the Japanese encephalitis serogroup, was first detected in North America following an epizootic in the New York City area in 1999. In the intervening 11 years since the arrival of the virus in North America, it has crossed the contiguous USA, entered the Canadian provinces bordering the USA, and has been reported in the Caribbean islands, Mexico, Central America and, more recently, South America. West Nile virus has been reported in over 300 species of birds in the USA and has caused the deaths of thousands of birds, local population declines of some avian species, the clinical illness and deaths of thousands of domestic horses, and the clinical disease in over 30 000 Americans and the deaths of over 1000. Prior to the emergence of West Nile virus in North America, St. Louis encephalitis virus and Dengue virus were the only other known mosquito-transmitted flaviviruses in North America capable of causing human disease. This review will discuss the North American experience with mosquito-borne flavivirus prior to the arrival of West Nile virus, the entry and spread of West Nile virus in North America, effects on wild bird populations, genetic changes in the virus, and the current state of West Nile virus transmission.

  4. West European magnetic confinement fusion research

    International Nuclear Information System (INIS)

    McKenney, B.L.; McGrain, M.; Hogan, J.T.; Porkolab, M.; Thomassen, K.I.

    1990-01-01

    This report presents a technical assessment and review of the West European program in magnetic confinement fusion by a panel of US scientists and engineers active in fusion research. Findings are based on the scientific and technical literature, on laboratory reports and preprints, and on the personal experiences and collaborations of the panel members. Concerned primarily with developments during the past 10 years, from 1979 to 1989, the report assesses West European fusion research in seven technical areas: tokamak experiments; magnetic confinement technology and engineering; fusion nuclear technology; alternate concepts; theory; fusion computations; and program organization. The main conclusion emerging from the analysis is that West European fusion research has attained a position of leadership in the international fusion program. This distinction reflects in large measure the remarkable achievements of the Joint European Torus (JET). However, West European fusion prominence extends beyond tokamak experimental physics: the program has demonstrated a breadth of skill in fusion science and technology that is not excelled in the international effort. It is expected that the West European primacy in central areas of confinement physics will be maintained or even increased during the early 1990s. The program's maturity and commitment kindle expectations of dramatic West European advances toward the fusion energy goal. For example, achievement of fusion breakeven is expected first in JET, before 1995

  5. Do the Atlantic climate modes impact the ventilation of the eastern tropical North Atlantic oxygen minimum zones?

    Science.gov (United States)

    Burmeister, Kristin; Lübbecke, Joke F.

    2017-04-01

    Oxygen minimum zones (OMZs) exist in the upwelling regions of the eastern tropical Atlantic and Pacific at intermediate depth. They are a consequence of high biological productivity in combination with weak ventilation. The flow fields in the tropical Atlantic is characterized by Latitudinally Alternating Zonal Jets (LAZJs) with a large vertical scale. It has been suggested that LAZJs play an important role for the ventilation of the OMZ as eastward currents advect oxygen-rich waters from the western boundary towards the OMZ. In the Eastern Tropical North Atlantic (ETNA), the eastward flowing North Equatorial Undercurrent and North Equatorial Countercurrent (NECC) provide the main oxygen supply into the OMZ. Variability in the strength and location of the LAZJs is associated with oxygen variability in the ETNA OMZ. We here want to address the question whether the variability in the zonal current field can be partly attributed to the large-scale climate modes of the tropical Atlantic, namely the Atlantic zonal and meridional mode. An influence of these modes on the NECC has been found in previous studies. For the analysis we are using the output of a global ocean circulation model, in which a 1/10° nest covering the tropical Atlantic is embedded into a global 1/2° model, as well as reanalysis products and satellite data. The zonal current field and oxygen distribution from the high resolution model is compared to observational data. The location and intensity of the current bands during positive and negative phases of the Atlantic climate modes are compared by focusing on individual events and via composite analysis. Based on the results, the potential impact of the Atlantic climate modes on the ventilation of the ETNA OMZ is discussed.

  6. On the Currents and Transports Connected with the Atlantic Meridional Overtuning Circulation in the Subpolar North Atlantic

    Science.gov (United States)

    2013-08-14

    conveyor belt , Science, 328, 1507–1511. Lumpkin, R., K. G. Speer, and K. P. Koltermann (2008), Transport across 48N in the Atlantic Ocean, J. Phys...Fleet Numerical Meteorology and Oceanography Center 3 hourly, 0.5 Navy Operational Global Atmo- spheric Prediction System (NOGAPS [Rosmond et al...Smith (2007), Resolution convergence and sensitivity studies with North Atlantic circulation models. Part I: The western boundary current system

  7. Recent demographic history and present fine-scale structure in the Northwest Atlantic leatherback (Dermochelys coriacea turtle population.

    Directory of Open Access Journals (Sweden)

    Erica Molfetti

    Full Text Available The leatherback turtle Dermochelys coriacea is the most widely distributed sea turtle species in the world. It exhibits complex life traits: female homing and migration, migrations of juveniles and males that remain poorly known, and a strong climatic influence on resources, breeding success and sex-ratio. It is consequently challenging to understand population dynamics. Leatherbacks are critically endangered, yet the group from the Northwest Atlantic is currently considered to be under lower risk than other populations while hosting some of the largest rookeries. Here, we investigated the genetic diversity and the demographic history of contrasted rookeries from this group, namely two large nesting populations in French Guiana, and a smaller one in the French West Indies. We used 10 microsatellite loci, of which four are newly isolated, and mitochondrial DNA sequences of the control region and cytochrome b. Both mitochondrial and nuclear markers revealed that the Northwest Atlantic stock of leatherbacks derives from a single ancestral origin, but show current genetic structuration at the scale of nesting sites, with the maintenance of migrants amongst rookeries. Low nuclear genetic diversities are related to founder effects that followed consequent bottlenecks during the late Pleistocene/Holocene. Most probably in response to climatic oscillations, with a possible influence of early human hunting, female effective population sizes collapsed from 2 million to 200. Evidence of founder effects and high numbers of migrants make it possible to reconsider the population dynamics of the species, formerly considered as a metapopulation model: we propose a more relaxed island model, which we expect to be a key element in the currently observed recovering of populations. Although these Northwest Atlantic rookeries should be considered as a single evolutionary unit, we stress that local conservation efforts remain necessary since each nesting site hosts

  8. A new compilation of stomach content data for commercially important pelagic fish species in the northeast Atlantic

    Science.gov (United States)

    Pinnegar, J. K.; Goñi, N.; Trenkel, V. M.; Arrizabalaga, H.; Melle, W.; Keating, J.; Óskarsson, G.

    2015-02-01

    There is increasing demand for information on predator-prey interactions in the ocean as a result of legislative commitments aimed at achieving sustainable exploitation. However, comprehensive data sets are lacking for many fish species and this has hampered development of multispecies fisheries models and the formulation of effective food-web indicators. This work describes a new compilation of stomach content data for five pelagic fish species (herring, blue whiting, mackerel, albacore and bluefin tuna) sampled across the northeast Atlantic and submitted to the PANGAEA open-access data portal (blank">www.pangaea.de). We provide detailed descriptions of sample origin and of the corresponding database structures. We describe the main results in terms of diet composition and predator-prey relationships. The feeding preferences of small pelagic fish (herring, blue whiting, mackerel) were sampled over a very broad geographic area within the North Atlantic basin, from Greenland in the west, to the Lofoten Islands in the east and from the Bay of Biscay northwards to the Arctic. This analysis revealed significant differences in the prey items selected in different parts of the region at different times of year. Tunas (albacore and bluefin) were sampled in the Bay of Biscay and Celtic Sea. Dominant prey items for these species varied by location, year and season. This data compilation exercise represents one of the largest and most wide-ranging ever attempted for pelagic fish in the North Atlantic. The earliest data included in the database were collected in 1864, whereas the most recent were collected in 2012. Data sets are available at doi:10.1594/PANGAEA.820041 and doi:10.1594/PANGAEA.826992.

  9. A new compilation of stomach content data for commercially-important pelagic fish species in the Northeast Atlantic

    Science.gov (United States)

    Pinnegar, J. K.; Goñi, N.; Trenkel, V. M.; Arrizabalaga, H.; Melle, W.; Keating, J.; Óskarsson, G.

    2014-04-01

    There is increasing demand for information on predator-prey interactions in the ocean as a result of legislative commitments aimed at achieving sustainable exploitation. However, comprehensive datasets are lacking for many fish species and this has hampered development of multispecies fisheries models and the formulation of effective food-web indicators. This work describes a new compilation of stomach content data for five pelagic fish species (herring, blue whiting, mackerel, albacore and bluefin tuna) sampled across the northeast Atlantic and submitted to the PANGAEA open-access data portal (blank">www.pangaea.de). We provide detailed descriptions of sample origin and of the corresponding database structures. We describe the main results in terms of diet composition and predator-prey relationships. The feeding preferences of small pelagic fish (herring, blue whiting, mackerel) were sampled over a very broad geographic area within the North Atlantic basin, from Greenland in the west, to the Lofoten Islands in the east and from the Bay of Biscay northwards to the Arctic. This analysis revealed significant differences in the prey items selected in different parts of the region at different times of year. Tunas (albacore and bluefin) were sampled in the Bay of Biscay and Celtic Sea. Dominant prey items for these species varied by location, year and season. This data compilation exercise represents one of the largest and most wide-ranging ever attempted for pelagic fish in the north Atlantic. The earliest data included in the database were collected in 1864, whereas the most recent were collected in 2012.Datasets are available at blank">doi:10.1594/PANGAEA.820041 and blank">doi:10.1594/PANGAEA.826992.

  10. Diversity of late Neogene Monachinae (Carnivora, Phocidae) from the North Atlantic, with the description of two new species

    Science.gov (United States)

    Dewaele, Leonard; Peredo, Carlos Mauricio; Meyvisch, Pjotr; Louwye, Stephen

    2018-03-01

    While the diversity of `southern seals', or Monachinae, in the North Atlantic realm is currently limited to the Mediterranean monk seal, Monachus monachus, their diversity was much higher during the late Miocene and Pliocene. Although the fossil record of Monachinae from the North Atlantic is mainly composed of isolated specimens, many taxa have been erected on the basis of fragmentary and incomparable specimens. The humerus is commonly considered the most diagnostic postcranial bone. The research presented in this study limits the selection of type specimens for different fossil Monachinae to humeri and questions fossil taxa that have other types of bones as type specimens, such as for Terranectes parvus. In addition, it is essential that the humeri selected as type specimens are (almost) complete. This questions the validity of partial humeri selected as type specimens, such as for Terranectes magnus. This study revises Callophoca obscura, Homiphoca capensis and Pliophoca etrusca, all purportedly known from the Lee Creek Mine, Aurora, North Carolina, in addition to their respective type localities in Belgium, South Africa and Italy, respectively. C. obscura is retained as a monachine seal taxon that lived both on the east coast of North America and in the North Sea Basin. However, H. capensis from North America cannot be identified beyond the genus level, and specimens previously assigned to Pl. etrusca from North America clearly belong to different taxa. Indeed, we also present new material and describe two new genera of late Miocene and Pliocene Monachinae from the east coast of North America: Auroraphoca atlantica nov. gen. et nov. sp., and Virginiaphoca magurai nov. gen. et nov. sp. This suggests less faunal interchange of late Neogene Monachinae between the east and west coasts of the North Atlantic than previously expected.

  11. From transpression to trnstension along the west Barents margin: the Forlandsundet basin, W. Svalbard

    Science.gov (United States)

    Terje Osmundsen, Per; Redfield, Thomas F.; Ganerød, Morgan; Appleyard, Tyler; Peron-Pinvidic, Gwenn; Schaaf, Niklas

    2017-04-01

    The enigmatic and understudied Forlandsundet Basin in western Svalbard represents the outermost onshore Cenozoic basin along the NE Atlantic margin. It occupies a key location to understand the margińs tectono-sedimentary history as the margin switched from transpression to transtension in the late Paleogene. During Paleocene and Eocene time, the Barents segment of the NE Atlantic margin accommodated dextral shear between Svalbard and Greenland resulting in the formation of a transpressional orogen and associated foreland basin in western Spitsbergen. At anomaly 13 time (c. 33Ma), re-arrangement of the spreading system in the North Atlantic included formation of the obliquely ultraslow-spreading Knipovitch Ridge west of Spitsbergen. Ridge formation was preceded by a very dramatic reduction of crustal thickness west of Spitsbergen. The Forlandsundet Graben structure sits at the shoulder of a very narrow necking domain developed along parts of the sheared margin, where continental crust was thinned to a few kilometers or less over c. 100 km horizontal distance. The basin geometry is that of an asymmetric graben to half-graben filled with coarse continental-derived siliciclastics and finer-grained marine sediments. Parts of the outcropping stratigraphy represent continental-derived conglomeratic debris flows deposited into the marine environment. The basin is poorly dated but ages ranging from the Eocene to Early/Late Oligocene have been proposed by previous workers based on fossils and strontium isotope data. The basin is bound by normal/oblique faults that truncate the Paleocene-Eocene W. Spitsbergen fold and thrust belt, which may favor the Oligocene age. Both normal/oblique faults and contractional structures in the form of folds and thrusts are documented. Large-scale folds are oriented at an oblique to high angle compared with structures in the fold and thrust belt, but approximate the NW-SE maximum elongation trend as recorded by a number of oblique-slip and

  12. Climatic changes in the subtropical Southeast Atlantic: the St. Helena Island Climate Index (1893-1999) [review article

    Science.gov (United States)

    Feistel, Rainer; Hagen, Eberhard; Grant, Keith

    2003-10-01

    The Benguela upwelling system in the subtropical Southeast Atlantic is subject to dramatic interannual fluctuations sometimes termed ‘Benguela Niño’ events. The South Atlantic Anticyclone (SAA) is assumed to be the responsible climatic ‘activity centre’ for the south-east trade winds driving the upwelling processes along the Namibian and South-west African coasts. Air temperature and humidity signals of this region, modulated by upwelling-controlled sea surface temperature (SST), are carried by the trades towards St. Helena Island. The island’s 1893-1999 century-long monthly weather records of temperature, pressure and rainfall have been assembled and homogenized. They exhibit trends for decreasing precipitation (10 mm/100 year), increasing air temperature (0.9 °C/100 year), and decreasing air pressure (0.6 hPa/100 year). Their first empirical orthogonal eigenfunction (EOF) covers 46% of the total variance; its associated temporal coefficient is proposed as a ‘St. Helena Island Climate Index (HIX)’. Austral winter HIX has a 42% correlation with a remotely sensed SST-derived Benguela upwelling index, called intense Benguela upwelling, for the time period 1982-1999. Not yet identified Benguela Niños (1895, 1905, 1912, 1916, 1946) and years of strong Benguela upwelling (1911, 1922, 1967, 1976) are newly suggested by the HIX.

  13. A Roadmap for Future Security in the West Balkans

    National Research Council Canada - National Science Library

    Berzani, Roland

    2008-01-01

    ..., such as: the unlimited postponement and just definition of Kosovo's status, delays to the Euro- Atlantic integration process, minority and human rights issues, economic prosperity, and organized crime...

  14. Water Mass Variability at the Mid-Atlantic Ridge and in the Eastern North Atlantic

    Science.gov (United States)

    Köllner, Manuela; Klein, Birgit; Kieke, Dagmar; Klein, Holger; Roessler, Achim; Rhein, Monika

    2017-04-01

    The strong warming and salinification of the Eastern North Atlantic starting in the mid 1990s has been attributed to a westward contraction of the sub-polar gyre and stronger inflow of waters from the sub-tropical gyre. Temporal changes in the shape and strength of the two gyres have been related to the major mode of atmospheric variability in the Atlantic sector, the NAO. Hydrographic conditions along the Northwest European shelf are thus the result of different processes such as variations in transports, varying relative contributions of water masses from the two gyres and property trends in the source water masses. The North Atlantic Current (NAC) can be regarded as the southern border of the sub-polar gyre transporting water from the tropical regions northward. On its way towards the Mid Atlantic Ridge (MAR) the NAC has partly mixed with waters from the sub-polar gyre and crosses the MAR split into several branches. For the study we analyzed data of water mass variability and transport fluctuations from the RACE (Regional circulation and Global change) project (2012-2015) which provided time series of transports and hydrographic anomalies from moored instruments at the western flank of the MAR. The time depending positions of the NAC branches over the MAR were obtained from mooring time series and compared to sea surface velocities from altimeter data. The results show a high variability of NAC pathways over the MAR. Transition regimes with strong meandering and eddies could be observed as well as periods of strong NAC branches over the Fracture Zones affecting water mass exchange at all depth levels. A positive temperature trend at depths between 1000-2000 m was found at the Faraday Fracture Zone (FFZ). This warming trend was also detected by Argo floats crossing the MAR close to the FFZ region. During the second phase of RACE (RACE-II, 2016-2018) a mooring array across the eastern shelf break at Goban Spur was deployed to monitor the poleward Eastern Boundary

  15. West Nile Virus in the United States — A Historical Perspective

    Directory of Open Access Journals (Sweden)

    John T. Roehrig

    2013-12-01

    Full Text Available Prior to 1999, West Nile virus (WNV was a bit player in the screenplay of global vector-borne viral diseases. First discovered in the West Nile District of Uganda in 1937, this Culex sp.-transmitted virus was known for causing small human febrile outbreaks in Africa and the Middle East. Prior to 1995, the last major human WNV outbreak was in the 1950s in Israel. The epidemiology and ecology of WNV began to change in the mid-1990s when an epidemic of human encephalitis occurred in Romania. The introduction of WNV into Eastern Europe was readily explained by bird migration between Africa and Europe. The movement of WNV from Africa to Europe could not, however, predict its surprising jump across the Atlantic Ocean to New York City and the surrounding areas of the United States (U.S.. This movement of WNV from the Eastern to Western Hemisphere in 1999, and its subsequent dissemination throughout two continents in less than ten years is widely recognized as one of the most significant events in arbovirology during the last two centuries. This paper documents the early events of the introduction into and the spread of WNV in the Western Hemisphere.

  16. WEST CORNWALL IN THE LANDSCAPE ABSTRACTION OF THE ST IVES SCHOOL

    Directory of Open Access Journals (Sweden)

    Дина Николаевна Алёшина

    2014-05-01

    Full Text Available The article is devoted to the British abstract painting of the St Ives School, which is world-famous but uninvestigated in Russia. The St Ives School taken its name from a little fishing town was formed in the South-West of England in the 1940 – 1950s. An object for study is a peculiarity of the abstract painting of the St. Ives School, its concreteness. For the first time the article researches a perception of a special place, where a centre of the abstract painting appeared, that was distinctive for British artists after the World War II. An image of West Cornwall is investigated in abstract landscapes of Bryan Wynter (1915 – 1975, Peter Lanyon (1918 – 1964, Roger Hilton (1911 – 1975 and Terry Frost (1915 – 2003. Methods of research include a detailed figuratively-stylistic and a comparative analysis of works and collation with its natural sources – landscapes of Cornwall. The article first studies images of Zennor and Newlyn, two famous places on the Atlantic coast, in the British abstract painting of the St Ives School.DOI: http://dx.doi.org/10.12731/2218-7405-2014-2-15

  17. Contingent Pacific–Atlantic Ocean influence on multicentury wildfire synchrony over western North America

    Science.gov (United States)

    Kitzberger, Thomas; Brown, Peter M.; Heyerdahl, Emily K.; Swetnam, Thomas W.; Veblen, Thomas T.

    2007-01-01

    Widespread synchronous wildfires driven by climatic variation, such as those that swept western North America during 1996, 2000, and 2002, can result in major environmental and societal impacts. Understanding relationships between continental-scale patterns of drought and modes of sea surface temperatures (SSTs) such as El Niño-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and Atlantic Multidecadal Oscillation (AMO) may explain how interannual to multidecadal variability in SSTs drives fire at continental scales. We used local wildfire chronologies reconstructed from fire scars on tree rings across western North America and independent reconstructions of SST developed from tree-ring widths at other sites to examine the relationships of multicentury patterns of climate and fire synchrony. From 33,039 annually resolved fire-scar dates at 238 sites (the largest paleofire record yet assembled), we examined forest fires at regional and subcontinental scales. Since 1550 CE, drought and forest fires covaried across the West, but in a manner contingent on SST modes. During certain phases of ENSO and PDO, fire was synchronous within broad subregions and sometimes asynchronous among those regions. In contrast, fires were most commonly synchronous across the West during warm phases of the AMO. ENSO and PDO were the main drivers of high-frequency variation in fire (interannual to decadal), whereas the AMO conditionally changed the strength and spatial influence of ENSO and PDO on wildfire occurrence at multidecadal scales. A current warming trend in AMO suggests that we may expect an increase in widespread, synchronous fires across the western U.S. in coming decades. PMID:17197425

  18. Contingent Pacific-Atlantic Ocean influence on multicentury wildfire synchrony over western North America.

    Science.gov (United States)

    Kitzberger, Thomas; Brown, Peter M; Heyerdahl, Emily K; Swetnam, Thomas W; Veblen, Thomas T

    2007-01-09

    Widespread synchronous wildfires driven by climatic variation, such as those that swept western North America during 1996, 2000, and 2002, can result in major environmental and societal impacts. Understanding relationships between continental-scale patterns of drought and modes of sea surface temperatures (SSTs) such as El Niño-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and Atlantic Multidecadal Oscillation (AMO) may explain how interannual to multidecadal variability in SSTs drives fire at continental scales. We used local wildfire chronologies reconstructed from fire scars on tree rings across western North America and independent reconstructions of SST developed from tree-ring widths at other sites to examine the relationships of multicentury patterns of climate and fire synchrony. From 33,039 annually resolved fire-scar dates at 238 sites (the largest paleofire record yet assembled), we examined forest fires at regional and subcontinental scales. Since 1550 CE, drought and forest fires covaried across the West, but in a manner contingent on SST modes. During certain phases of ENSO and PDO, fire was synchronous within broad subregions and sometimes asynchronous among those regions. In contrast, fires were most commonly synchronous across the West during warm phases of the AMO. ENSO and PDO were the main drivers of high-frequency variation in fire (interannual to decadal), whereas the AMO conditionally changed the strength and spatial influence of ENSO and PDO on wildfire occurrence at multidecadal scales. A current warming trend in AMO suggests that we may expect an increase in widespread, synchronous fires across the western U.S. in coming decades.

  19. An overview of chemosynthetic symbioses in bivalves from the North Atlantic and Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    S. Duperron

    2013-05-01

    Full Text Available Deep-sea bivalves found at hydrothermal vents, cold seeps and organic falls are sustained by chemosynthetic bacteria that ensure part or all of their carbon nutrition. These symbioses are of prime importance for the functioning of the ecosystems. Similar symbioses occur in other bivalve species living in shallow and coastal reduced habitats worldwide. In recent years, several deep-sea species have been investigated from continental margins around Europe, West Africa, eastern Americas, the Gulf of Mexico, and from hydrothermal vents on the Mid-Atlantic Ridge. In parallel, numerous, more easily accessible shallow marine species have been studied. Herein we provide a summary of the current knowledge available on chemosymbiotic bivalves in the area ranging west-to-east from the Gulf of Mexico to the Sea of Marmara, and north-to-south from the Arctic to the Gulf of Guinea. Characteristics of symbioses in 53 species from the area are summarized for each of the five bivalve families documented to harbor chemosynthetic symbionts (Mytilidae, Vesicomyidae, Solemyidae, Thyasiridae and Lucinidae. Comparisons are made between the families, with special emphasis on ecology, life cycle, and connectivity. Chemosynthetic symbioses are a major adaptation to ecosystems and habitats exposed to reducing conditions. However, relatively little is known regarding their diversity and functioning, apart from a few "model species" on which effort has focused over the last 30 yr. In the context of increasing concern about biodiversity and ecosystems, and increasing anthropogenic pressure on oceans, we advocate a better assessment of the diversity of bivalve symbioses in order to evaluate the capacities of these remarkable ecological and evolutionary units to withstand environmental change.

  20. An overview of chemosynthetic symbioses in bivalves from the North Atlantic and Mediterranean Sea

    Science.gov (United States)

    Duperron, S.; Gaudron, S. M.; Rodrigues, C. F.; Cunha, M. R.; Decker, C.; Olu, K.

    2013-05-01

    Deep-sea bivalves found at hydrothermal vents, cold seeps and organic falls are sustained by chemosynthetic bacteria that ensure part or all of their carbon nutrition. These symbioses are of prime importance for the functioning of the ecosystems. Similar symbioses occur in other bivalve species living in shallow and coastal reduced habitats worldwide. In recent years, several deep-sea species have been investigated from continental margins around Europe, West Africa, eastern Americas, the Gulf of Mexico, and from hydrothermal vents on the Mid-Atlantic Ridge. In parallel, numerous, more easily accessible shallow marine species have been studied. Herein we provide a summary of the current knowledge available on chemosymbiotic bivalves in the area ranging west-to-east from the Gulf of Mexico to the Sea of Marmara, and north-to-south from the Arctic to the Gulf of Guinea. Characteristics of symbioses in 53 species from the area are summarized for each of the five bivalve families documented to harbor chemosynthetic symbionts (Mytilidae, Vesicomyidae, Solemyidae, Thyasiridae and Lucinidae). Comparisons are made between the families, with special emphasis on ecology, life cycle, and connectivity. Chemosynthetic symbioses are a major adaptation to ecosystems and habitats exposed to reducing conditions. However, relatively little is known regarding their diversity and functioning, apart from a few "model species" on which effort has focused over the last 30 yr. In the context of increasing concern about biodiversity and ecosystems, and increasing anthropogenic pressure on oceans, we advocate a better assessment of the diversity of bivalve symbioses in order to evaluate the capacities of these remarkable ecological and evolutionary units to withstand environmental change.

  1. 78 FR 70509 - Fisheries Off West Coast States; Modifications of the West Coast Commercial and Recreational...

    Science.gov (United States)

    2013-11-26

    ...: Modification of fishing seasons; request for comments. SUMMARY: NOAA Fisheries announces 23 inseason actions in... allowing fishers access to the available fish at the time the fish were available while ensuring that.... 130108020-3409-01] RIN 0648-XC964 Fisheries Off West Coast States; Modifications of the West Coast...

  2. Changes in North Atlantic nitrogen fixation controlled by ocean circulation.

    Science.gov (United States)

    Straub, Marietta; Sigman, Daniel M; Ren, Haojia; Martínez-García, Alfredo; Meckler, A Nele; Hain, Mathis P; Haug, Gerald H

    2013-09-12

    In the ocean, the chemical forms of nitrogen that are readily available for biological use (known collectively as 'fixed' nitrogen) fuel the global phytoplankton productivity that exports carbon to the deep ocean. Accordingly, variation in the oceanic fixed nitrogen reservoir has been proposed as a cause of glacial-interglacial changes in atmospheric carbon dioxide concentration. Marine nitrogen fixation, which produces most of the ocean's fixed nitrogen, is thought to be affected by multiple factors, including ocean temperature and the availability of iron and phosphorus. Here we reconstruct changes in North Atlantic nitrogen fixation over the past 160,000 years from the shell-bound nitrogen isotope ratio ((15)N/(14)N) of planktonic foraminifera in Caribbean Sea sediments. The observed changes cannot be explained by reconstructed changes in temperature, the supply of (iron-bearing) dust or water column denitrification. We identify a strong, roughly 23,000-year cycle in nitrogen fixation and suggest that it is a response to orbitally driven changes in equatorial Atlantic upwelling, which imports 'excess' phosphorus (phosphorus in stoichiometric excess of fixed nitrogen) into the tropical North Atlantic surface. In addition, we find that nitrogen fixation was reduced during glacial stages 6 and 4, when North Atlantic Deep Water had shoaled to become glacial North Atlantic intermediate water, which isolated the Atlantic thermocline from excess phosphorus-rich mid-depth waters that today enter from the Southern Ocean. Although modern studies have yielded diverse views of the controls on nitrogen fixation, our palaeobiogeochemical data suggest that excess phosphorus is the master variable in the North Atlantic Ocean and indicate that the variations in its supply over the most recent glacial cycle were dominated by the response of regional ocean circulation to the orbital cycles.

  3. Fires, East Falkland Island, South Atlantic

    Science.gov (United States)

    2007-01-01

    This near-nadir image (looking almost straight down) of the Falkland Islands in the South Atlantic was acquired at the southernmost extent of the International Space Station's latitudinal orbit range of approximately 52 degrees north to 52 degrees south relative to the surface of the Earth. The windy and relatively dry climate, which includes roughly 600 millimeters (24 inches) of precipitation annually, has given rise to natural vegetation comprised of treeless grassland with scattered bogs. The grasslands are ideal for sheep rearing--the dominant occupation until recent decades, when fishing (mainly squid for Spain) and tourism became the mainstays of the economy. These expanses of grassland provide ready fuel for fires, as indicated by the several long smoke plumes visible in this astronaut photograph. Astronaut photograph ISS015-E-30526 was acquired on September 25, 2007, with a Kodak 760C digital camera fitted with a 58 mm lens. The image was taken by the Expedition 15 crew, and is provided by the ISS Crew Earth Observations experiment and Image Science and Analysis Laboratory, Johnson Space Center. The image in this article has been cropped and enhanced to improve contrast. Lens artifacts have been removed.

  4. Trans Atlantic Infrasound Payload (TAIP) Operation Plan.

    Energy Technology Data Exchange (ETDEWEB)

    Bowman, Daniel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lees, Jonathan M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2018-01-01

    The Carolina Infrasound package, added as a piggyback to the 2016 ULDB ight, recorded unique acoustic signals such as the ocean microbarom and a large meteor. These data both yielded unique insights into the acoustic energy transfer from the lower to the upper atmosphere as well as highlighted the vast array of signals whose origins remain unknown. Now, the opportunity to y a payload across the north Atlantic offers an opportunity to sample one of the most active ocean microbarom sources on Earth. Improvements in payload capabilities should result in characterization of the higher frequency range of the stratospheric infrasound spectrum as well. Finally, numerous large mining and munitions disposal explosions in the region may provide \\ground truth" events for assessing the detection capability of infrasound microphones in the stratosphere. The flight will include three different types of infrasound sensors. One type is a pair of polarity reversed InfraBSU microphones (standard for high altitude flights since 2016), another is a highly sensitive Chaparral 60 modified for a very low corner period, and the final sensor is a lightweight, low power Gem infrasound package. By evaluating these configurations against each other on the same flight, we will be able to optimize future campaigns with different sensitivity and mass constraints.

  5. Transports along and across the north-west European shelf edge

    Science.gov (United States)

    Huthnance, J.; Hopkins, J.; Jones, S. C.; Loveday, B. R.; Miller, P. I.; Porter, M.; Simpson, J.; Spingys, C.; Stashchuk, N.; Vlasenko, V.; Guihou, K.; Inall, M. E.; Xu, W.

    2016-02-01

    The project FASTNEt - Fluxes across sloping topography of the North East Atlantic - has made a variety of measurements in three contrasted sectors of shelf edge: the Celtic Sea south-west of Britain, the Malin-Hebrides shelf west of Scotland and the West Shetland shelf north of Scotland. Previous studies established the existence of flow along the continental slope in these areas, more persistently poleward in more northern sectors. Modelling is under way to diagnose and estimate the contribution of various processes to transports and exchange along and across the slope. This presentation describes estimates obtained so far; overall transport estimates from drifters and moored current meters; effective "diffusivity" from drifter dispersion and salinity surveys; other estimates of velocity variance contributing to exchange. In addition to transport by the along-slope flow, possible process contributions which may be estimated include internal waves and their Stokes drift, tidal pumping, eddies and Ekman transports, in a wind-driven surface layer and in a bottom boundary layer. Overall estimates of exchange across the shelf edge are large, several m2/s (Sverdrups per 1000 km). However, the large majority of this is in tides and other motion of comparably short period, and is only effective for water properties that evolve on a time-scale of a day or less. Exchange due to motion with periods exceeding two days was of order 1 m2/s (2 m2/s) at the Celtic Sea (Malin) shelf edge from short-duration moorings: 11(12) days respectively. An 11-month mooring in deeper water (1000 m) off the Celtic Sea gave equivalent monthly values from 8 to 20 m2/s.

  6. 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.)

  7. 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.

  8. 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.

  9. Diel and seasonal variation in food habits of Atlantic salmon parr in a small stream

    Science.gov (United States)

    Grader, M.; Letcher, B.H.

    2006-01-01

    The diel and seasonal food habits of young-of-year (YOY) and post-young-of-year (PYOY) Atlantic salmon (Salmo salar) parr were assayed over the course of 11 months in the West Brook, Massachusetts USA. Gut fullness of YOY salmon did not vary significantly among months. PYOY salmon exhibited significant seasonal differences in gut fullness, with peak fullness occurring in the spring and late fall. Significant diel differences in PYOY gut fullness occurred in June and April, with peak fullness always occurring at dawn. Prey composition varied substantially among months. Dominant prey items of PYOY salmon were baetid mayflies in June, July, and August, limnephilid caddisflies in October and November, and ephemerellid mayflies in February and April. Few differences in prey composition between PYOY and YOY salmon were observed. Fish growth was unrelated to prey availability, but gut fullness explained up to 97% of growth variation across seasons. Results suggest that spring and fall are critical periods of feeding for PYOY salmon and that diel feeding intensity shifts seasonally.

  10. Millennial-scale northern Hemisphere Atlantic-Pacific climate teleconnections in the earliest Middle Pleistocene.

    Science.gov (United States)

    Hyodo, Masayuki; Bradák, Balázs; Okada, Makoto; Katoh, Shigehiro; Kitaba, Ikuko; Dettman, David L; Hayashi, Hiroki; Kumazawa, Koyo; Hirose, Kotaro; Kazaoka, Osamu; Shikoku, Kizuku; Kitamura, Akihisa

    2017-08-30

    Suborbital-scale climate variations, possibly caused by solar activity, are observed in the Holocene and last-glacial climates. Recently published bicentennial-resolution paleoceanic environmental records reveal millennial-scale high-amplitude oscillations postdating the last geomagnetic reversal in the Marine Isotope Stage (MIS) 19 interglacial. These oscillations, together with decoupling of post-reversal warming from maximum sea-level highstand in mid-latitudes, are key features for understanding the climate system of MIS 19 and the following Middle Pleistocene. It is unclear whether the oscillations are synchronous, or have the same driver as Holocene cycles. Here we present a high resolution record of western North Pacific submarine anoxia and sea surface bioproductivity from the Chiba Section, central Japan. The record reveals many oxic events in MIS 19, coincident with cold intervals, or with combined cold and sea-level fall events. This allows detailed correlations with paleoceanic records from the mid-latitude North Atlantic and Osaka Bay, southwest Japan. We find that the millennial-scale oscillations are synchronous between East and West hemispheres. In addition, during the two warmest intervals, bioproductivity follows the same pattern of change modulated by bicentennial cycles that are possibly related to solar activity.

  11. Ectoparasites of bats (Mammalia: Chiroptera) in Atlantic forest fragments in north-eastern Brazil.

    Science.gov (United States)

    Bezerra, Rayanna Hellem Santos; de Vasconcelos, Pedro Fonseca; Bocchiglieri, Adriana

    2016-10-01

    In Brazil, most studies involving parasites of bats (bat flies) treat the mid-west, south-east, and south of the country. This work aimed to characterize the ectoparasites community associated with bats in the Atlantic forest in the state of Sergipe, north-eastern Brazil. Sampling was conducted between January and June 2013 in the Serra de Itabaiana National Park (PNSI) and between November 2013 and June 2015 in the Wildlife Refuge Mata do Junco (RVSMJ). Parasitological indexes were determined, and the influence of host sex and the seasonality in prevalence rates and mean intensity for the most abundant parasites was evaluated. Some 129 parasites were collected in PNSI and 296 in RVSMJ, and 100 and 70.6 %, respectively, belong to the family Streblidae. The differences in parasitological rates in Sergipe in relation to other studies may be associated with the environmental characteristics and the composition of the host community. The influence of sex and the seasonal prevalence of Speiseria ambigua and Trichobius joblingi, associated with Carollia perspicillata, may be associated with a lower rate of female captures and low sampling in the dry season. This is a pioneer study in Sergipe that reveals the occurrence of 16 species of streblids and representatives of Acari and Basilia spp., highlighting the need for more studies to increase the wealth and understanding of host-parasite associations in the state.

  12. The uptake of macroplastic & microplastic by demersal & pelagic fish in the Northeast Atlantic around Scotland.

    Science.gov (United States)

    Murphy, Fionn; Russell, Marie; Ewins, Ciaran; Quinn, Brian

    2017-09-15

    This study reports plastic ingestion in various fish found from coastal and offshore sites in Scottish marine waters. Coastal samples consisted of three demersal flatfish species (n=128) collected from the East and West coasts of Scotland. Offshore samples consisted of 5 pelagic species and 4 demersal species (n=84) collected from the Northeast Atlantic. From the coastal fish sampled, 47.7% of the gastrointestinal tracts contained macroplastic and microplastic. Of the 84 pelagic and demersal offshore fish, only 2 (2.4%) individuals from different species had ingested plastic identified as a clear polystyrene fibre and a black polyamide fibre. The average number of plastic items found per fish from all locations that had ingested plastic was 1.8 (±1.7) with polyamide (65.3%), polyethylene terephthalate (14.4%) and acrylic (14.4%) being the three most commonly found plastics. This study adds to the existing data on macroplastic and microplastic ingestion in fish species. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  13. Central Atlantic Lithosphere-Asthenosphere Boundary Study (CAL-LAB): Massive Coast effects in MT data

    Science.gov (United States)

    Reyes Ortega, V.; Constable, S.; Bassett, D.

    2017-12-01

    The Lithosphere-Asthenosphere Boundary (LAB) is the largest plate boundary on Earth yet is still poorly understood, with temperature, hydration, composition, melting, strain rate, and anisotropy all candidates to explain the location and behavior of this transition from convecting asthenosphere to rigid lithosphere. Electrical conductivity, estimated from magnetotelluric (MT) data and combined with seismic measurements, is increasingly being seen as a way to improve our understanding of the LAB. The Integrated LAB (iLAB) experiment brings together three institutions from three countries to collect MT data along with passive and active seismic data in the central equatorial Atlantic, over lithosphere from 0 to 80 My old. Thirty-nine seafloor MT instruments were deployed alongside ocean-bottom seismometers for over one year, and recorded data for 70 to 100 days before the batteries expired. Good quality MT responses were obtained from 10 to nearly 100,000 seconds period, but many sites exhibited up to -180 degree phase shifts at the highest frequencies. Forward modeling shows that this behavior is consistent with a coast effect from the African coastline 500-1500 kilometers away. The conductive mid-ocean ridge system modifies the coast effect for sites west of the ridge. Inverting these data for LAB geology in the presence of such a strong coast effect presents a considerable challenge.

  14. Age and growth of the southern blue whiting Micromesistius australis in the SW Atlantic

    Directory of Open Access Journals (Sweden)

    Maria Cristina Cassia

    2000-09-01

    Full Text Available Age and growth of southern blue whiting Micromesistius australis are studied. Sagitta otoliths from 3650 specimens were used for age determination. These were taken during research surveys and commercial catches in the South West Atlantic during 1994 and 1995. The size of fishes ranged from 17 to 60 cm total length, corresponding to ages 0 to 23 years. Females attained a greater asymptotic length (L? 59.74 cm than males (L? 54.72 cm. Comparison of growth curves by the likelihood ratio showed that the differences among females and males were due to the asymptotic length, while the other parameters (K and t0 were not statistically different. The mean weight-at-age, mean length-at-age, and total mortality (Z were estimated. Growth parameters estimated by sex in the period 1994-95, mean size per age group, and the number of individuals per age in the catches show differences with those calculated when the population was in the early stage of exploitation. A predominance of 2 to 9 year old individuals was observed in the total catches in 1994-1995, whereas in the beginning of the fisheries total catches were basically fish 15 to 19 years old.

  15. Impacts of Tropical North Atlantic SST on Western North Pacific Landfalling Tropical Cyclones

    Science.gov (United States)

    Zhang, W.; Gao, S.; Chen, Z.

    2017-12-01

    This study examines the impacts of tropical North Atlantic (TNA) sea surface temperature (SST) anomaly (SSTA) on tropical cyclones (TCs) making landfall over East Asia. We find that TNA SSTA has significant negative correlations with the frequency of TCs making landfall over China, Vietnam, Korea and Japan, and the entire East Asia. TNA SST influences the frequency of TC landfalls over these regions by regulating TC genesis location and frequency and steering flow associated with modulated environmental conditions. During cold TNA SST years, larger low-level relative vorticity and weaker vertical wind shear lead to more TC formations in the northern SCS and to the east of Philippines, and larger low-level relative vorticity, higher mid-level relative humidity, and weaker vertical wind shear result in more TC formations over the eastern part of WNP. Anomalous northeasterly steering flow favors more TCs to move westward or west-northwestward and make landfall over Vietnam, South China and Taiwan Island and thus in the entire China, and more TCs take regular northeastward recurving tracks and make landfall over Korea and Japan because of insignificant steering flow anomalies in the vicinity. The modulation of large-scale environments by TNA SSTA may be through two possible pathways proposed in previous studies, i.e., Indian Ocean relaying effect and subtropical eastern Pacific relaying effect. Our results suggest that TNA SSTA is a potential predictor for the frequency of TCs making landfall over China, Vietnam, Korea and Japan, and the entire East Asia.

  16. Deepwater Horizon oil spill impacts on sea turtles could span the Atlantic.

    Science.gov (United States)

    Putman, Nathan F; Abreu-Grobois, F Alberto; Iturbe-Darkistade, Iñaky; Putman, Emily M; Richards, Paul M; Verley, Philippe

    2015-12-01

    We investigated the extent that the 2010 Deepwater Horizon oil spill potentially affected oceanic-stage sea turtles from populations across the Atlantic. Within an ocean-circulation model, particles were backtracked from the Gulf of Mexico spill site to determine the probability of young turtles arriving in this area from major nesting beaches. The abundance of turtles in the vicinity of the oil spill was derived by forward-tracking particles from focal beaches and integrating population size, oceanic-stage duration and stage-specific survival rates. Simulations indicated that 321 401 (66 199-397 864) green (Chelonia mydas), loggerhead (Caretta caretta) and Kemp's ridley (Lepidochelys kempii) turtles were likely within the spill site. These predictions compared favourably with estimates from in-water observations recently made available to the public (though our initial predictions for Kemp's ridley were substantially lower than in-water estimates, better agreement was obtained with modifications to mimic behaviour of young Kemp's ridley turtles in the northern Gulf). Simulations predicted 75.2% (71.9-76.3%) of turtles came from Mexico, 14.8% (11-18%) from Costa Rica, 5.9% (4.8-7.9%) from countries in northern South America, 3.4% (2.4-3.5%) from the United States and 1.6% (0.6-2.0%) from West African countries. Thus, the spill's impacts may extend far beyond the current focus on the northern Gulf of Mexico. © 2015 The Authors.

  17. Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Mid-Atlantic): Weakfish

    Science.gov (United States)

    1989-08-01

    IDENTIFICATION AIDS Class ............. ... Osteichthyes Oraer ............. ... Perciformes The following description is that of Family...Angler’s guide to the United fying western Atlantic Sciaenidae States Atlantic coast. Section II, (Teleostei: Perciformes ). U.S. Dep. Nantucket Shoals to

  18. 50 CFR 229.36 - Atlantic Pelagic Longline Take Reduction Plan (PLTRP).

    Science.gov (United States)

    2010-10-01

    ... the U.S. east coast, a component of the Atlantic Ocean, Caribbean, Gulf of Mexico large pelagics... and operator of any vessel that has been issued or is required to be issued an Atlantic HMS tunas...

  19. 77 FR 16811 - Mid-Atlantic Fishery Management Council (MAFMC); Public Meetings

    Science.gov (United States)

    2012-03-22

    ... Organizational Reports, the South Atlantic Liaison Report, Executive Director's Report, Science Report, Committee... from NOAA General Counsel, discuss integration of the Scientific and Statistical Committee (SSC) into... minutes, receive Organizational Reports, the South Atlantic Liaison Report, the Executive Director's...

  20. 75 FR 8673 - Mid-Atlantic Fishery Management Council; Public Meeting

    Science.gov (United States)

    2010-02-25

    ... Fishery Management Council; Public Meeting AGENCY: National Marine Fisheries Service (NMFS), National... Mid-Atlantic Fishery Management Council (Council) will conduct an educational workshop on catch shares in cooperation with the Fisheries Leadership and Sustainability Forum (FLSF), the Atlantic States...

  1. Overturn of the Oceasn Flow in the North Atlantic as a Trigger of Inertia Motion to Form a Meridional Ocean Circulation

    Science.gov (United States)

    Nakamura, Shigehisa

    2010-05-01

    This work is an introduction of a meridional ocean circulation. As for the zonal motions,there have been many contributions. Recent oceanographic works noticed an overturn of the ocean current in the North Atlantic. The author notices this overturn is a trigger to generate a meridional ocean circulation to have a track through the deep Atlantic, the deep circum-polar current, the deep branch flow to the Pacific between the Australian and the South America. The east part of the branch flow relates to the upwelling off Peru, and the west part relates to form a deep water in the Northwest Pacific. THe overturn of the North Atlantic suggests an outflow of the deep water and a storage of the old aged deep water in the Northwest Pacific. The storage water increase in the Northwest Pacific shoould be a trigger of the swelling up of the sea level mid Pacific to affect to the ocean front variations between the coastal waters and the ocean water. In order to keep a hydrodynamic balance on the earth, an increase of the deep water in the Pacific should flow through the Bering Sea and the Arctic Sea to get to the North Atlantic. It should be noted that a budget of the ocean water flow must be hold the condition of the water masses concservation on the earth surface. This inertia motion is maintained once induced after any natural effect or some man-made influences. At this stage, the author has to notice that there has been developed a meridional inertia path of the air particle as well as the ocean water parcel, nevertheless nobody has had pointed out this inertiamotion with a meridional path in the ocean. Air-sea interaction must be one of the main factors for driving the ocean water though the inertia motion in the global scale is more energetic. To the details, the scientists should pursue what geophysical dynamics must be developed in the future.

  2. The impact of different hydrographic conditions and zooplankton communities on provisioning Little Auks along the West coast of Spitsbergen

    Science.gov (United States)

    Kwasniewski, Slawomir; Gluchowska, Marta; Jakubas, Dariusz; Wojczulanis-Jakubas, Katarzyna; Walkusz, Wojciech; Karnovsky, Nina; Blachowiak-Samolyk, Katarzyna; Cisek, Malgorzata; Stempniewicz, Lech

    2010-10-01

    Composition and abundance of zooplankton were studied simultaneously with feeding ecology of planktivorous Little Auks ( Alle alle) in two different sea shelf areas of West Spitsbergen, Norway, in summer 2007. Zooplankton was collected adjacent to bird colonies in Magdalenefjorden (influenced by Atlantic West Spitsbergen Current) and Hornsund (dominated by the Arctic Sørkapp Current). In spite of different hydrological situations, the abundance of prey preferred by Little Auks, Arctic Calanus glacialis copepodids stage V, among zooplankton was similar in both localities. However, there was much more of Atlantic Calanus finmarchicus on the shelf outside Magdalenefjorden compared to Hornsund, resulting in different abundance ratios of Arctic to Atlantic copepods in the two areas (1:14 and 1:1, respectively). Even greater differences between the two areas occurred in the ratio of C. glacialis CV to other zooplankters, amounting to 1:40 in Magdalenefjorden and 1:6 in Hornsund. In both Little Auk colonies food brought by parents to their chicks contained mainly C. glacialis CV, albeit the proportion of this copepod in meals was significantly higher in Hornsund. Meals delivered to Little Auk chicks in Hornsund had also higher zooplankton numbers, biomass and energy content. In Magdalenefjorden, on the other hand, a higher number of feedings and longer duration of foraging trips were recorded. These differences became more apparent with increasing energy requirements of the fast growing nestlings. This was probably a consequence of lower relative abundance of the Little Auks’ preferred prey in the sea adjacent to Magdalenefjorden colony. It seems that searching for the preferred food items, such as C. glacialis, among abundant but less favored C. finmarchicus, may require more time and energy demanding foraging behavior. As a consequence, foraging effort of the Little Auk parents from Magdalenefjorden was higher, and feeding efficiency lower, than those of birds from

  3. West German Jewry: Guilt, Power and Pluralism

    Directory of Open Access Journals (Sweden)

    Anthony d. Kauders

    2010-04-01

    Full Text Available The essay will address the history of West German Jewry using the concept of guilt as its guiding theme. Jews in West Germany had a bad conscience on account of living in the “land of the murderers.” This bad conscience not only distinguished them from other Jewish communities, it also explains much of what characterized West German Jewry from 1945 to 1989: its particular economic structure; its especially close ties to Israel; its preoccupation with democratization; its power arrangements; and its communal life. The essay will address these issues, and trace a development that led from a close-knit, ideologically homogeneous group to one that became ever more pluralistic in the 1970s and 1980s.

  4. West African spatial patterns of economic activities

    DEFF Research Database (Denmark)

    Walther, Olivier; Howard, Allen; Retaillé, Denis

    2015-01-01

    Over the last 30 years, two different bodies of literature developed by both US historians and francophone geographers have moved toward similar conclusions regarding West African economic spatial patterns. Despite their different backgrounds, both the ‘spatial factor’ approach promoted by histor......Over the last 30 years, two different bodies of literature developed by both US historians and francophone geographers have moved toward similar conclusions regarding West African economic spatial patterns. Despite their different backgrounds, both the ‘spatial factor’ approach promoted...... traders, and where their differences lie. Finally, we show how a combined approach can make a significant contribution to the scholarly study of space in West Africa. We argue that continuing dialogue among fields can contribute to a reassessment of development policies....

  5. Sea Ice and Hydrographic Variability in the Northwest North Atlantic

    Science.gov (United States)

    Fenty, I. G.; Heimbach, P.; Wunsch, C. I.

    2010-12-01

    Sea ice anomalies in the Northwest North Atlantic's Labrador Sea are of climatic interest because of known and hypothesized feedbacks with hydrographic anomalies, deep convection/mode water formation, and Northern Hemisphere atmospheric patterns. As greenhouse gas concentrations increase, hydrographic anomalies formed in the Arctic Ocean associated with warming will propagate into the Labrador Sea via the Fram Strait/West Greenland Current and the Canadian Archipelago/Baffin Island Current. Therefore, understanding the dynamical response of sea ice in the basin to hydrographic anomalies is essential for the prediction and interpretation of future high-latitude climate change. Historically, efforts to quantify the link between the observed sea ice and hydrographic variability in the region has been limited due to in situ observation paucity and technical challenges associated with synthesizing ocean and sea ice observations with numerical models. To elaborate the relationship between sea ice and ocean variability, we create three one-year (1992-1993, 1996-1997, 2003-2004) three-dimensional time-varying reconstructions of the ocean and sea ice state in Labrador Sea and Baffin Bay. The reconstructions are syntheses of a regional coupled 32 km ocean-sea ice model with a suite of contemporary in situ and satellite hydrographic and ice data using the adjoint method. The model and data are made consistent, in a least-squares sense, by iteratively adjusting several model control variables (e.g., ocean initial and lateral boundary conditions and the atmospheric state) to minimize an uncertainty-weighted model-data misfit cost function. The reconstructions reveal that the ice pack attains a state of quasi-equilibrium in mid-March (the annual sea ice maximum) in which the total ice-covered area reaches a steady state -ice production and dynamical divergence along the coasts balances dynamical convergence and melt along the pack’s seaward edge. Sea ice advected to the

  6. Paintings in Atlantic Megalithic Art: Barnenez

    Directory of Open Access Journals (Sweden)

    Bueno Ramírez, Primitiva

    2012-06-01

    Full Text Available The use of technique is usually considered in European megalithic art as an indicator of the level of culture sophistication attained by a particular community. Traditionally, it was considered that only the Iberian Peninsula is home to painted dolmens. The analysis of chamber H of the Barnenez tumulus together with some information scattered over the continent, prove that painting was part of the graphic programs in the most archetypal Atlantic sites, such as Brittany. A highly rewarding panorama appears for European megalithic art with potential new readings. The most suitable method of detecting paintings and interpreting them in funerary contexts must be reviewed.

    La técnica ha venido estableciéndose en el arte megalítico europeo como una categoría cultural. Solo la Península Ibérica disponía de dólmenes pintados. Pero algunos datos dispersos en el resto del continente, junto con los análisis que se aportan procedentes de la cámara H del túmulo de Barnenez, certifican que la pintura formó parte de los programas gráfi cos de los más clásicos conjuntos atlánticos, como es el bretón. Se abre un panorama muy enriquecedor de nuevas lecturas para un arte megalítico europeo en el que habrá de contemplarse la metodología pertinente para la detección de pinturas y su interpretación en los discursos funerarios.

  7. 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.

  8. Middle Eocene paleocirculation of the southwestern Atlantic Ocean, the anteroom to an ice-house world: evidence from dinoflagellates

    Science.gov (United States)

    Raquel Guerstein, G.; Daners, Gloria; Palma, Elbio; Ferreira, Elizabete P.; Premaor, Eduardo; Amenábar, Cecilia R.; Belgaburo, Alexandra

    2016-04-01

    Middle Eocene dinoflagellate cyst organic walled assemblages from sections located in the Antarctic Peninsula, Tierra del Fuego, Santa Cruz province and south of Chile are mainly represented by endemic taxa, which are also dominant in several circum - Antarctic sites located southern 45° S. Some members of this endemic Antarctic assemblage, including especies of Enneadocysta, Deflandrea, Vozzhennikovia, and Spinidinium, have been recognised in sites along the Southwest Atlantic Ocean Shelf at Colorado (˜38° S), Punta del Este (˜36° S) and Pelotas (˜30° S) basins. Northern 30° S, at Jequitinhonha (˜17oS) and Sergipe (˜11° S) basins, there is no evidence of the endemic Antarctic members, except for Enneadocysta dictyostila, recorded in very low proportion. Based on its positive correlation with CaCO3 percentages we assume that this species is the unique member of the endemic assemblage apparently tolerant to warm surface waters. Previous research developed in the Tasman area has related the presence of endemic taxa at mid- latitudes to a strong clockwise subpolar gyre favoured by the partial continental blockage of the Tasmanian Gateways and the Drake Passage. In this work we propose that the dinoflagellate cyst distribution along the South Atlantic Ocean Shelf can be explained by a similar dynamical mechanism induced by a cyclonic subpolar gyre on the South Atlantic Ocean. The western boundary current of this gyre, starting on the west Antarctic continental slope, would follow a similar path to the present Malvinas Current on the Patagonian slope. Modelling and observational studies at the Patagonian shelf-break have shown that a cyclonic western boundary current promotes upwelling and intrusion of cold oceanic waters to the shelf and intensifies the northward shelf transport. In a similar way we hypothesize that during the Middle Eocene the western boundary current of a proto-Weddell Gyre transported the circum-antarctic waters and the endemic components

  9. Warm water events - Benguela Niños - in the southeast Atlantic Ocean since the beginning of the last century

    Science.gov (United States)

    Rathmann, J.; Jacobeit, J.

    2009-04-01

    The occasional occurrence of anomalous warm water events in the upwelling regions of the Benguela Current, so called Benguela Niños (BNs), has striking effects on regional rainfall and on the local ecosystem, hence on the fisheries. However, whereas BNs have been studied based on data for the recent years, long-term studies are still lacking. Long-term trend analyses demonstrate a strong increase in the SSTs of the southern Atlantic whereas precipitation shows a high variability but no significant long-term trend pattern in the region of Angola and Namibia. Thus, the study focuses on extreme precipitation events as a possible result of BNs. The present study is based on monthly observational data since 1901, including HadISST1.1 (1°x1° spatial resolution), HadSLP2 (5°x5°) and precipitation data (0.5°x0.5°), originally obtained from the Climatic Research Unit (Norwich) being updated and improved within the Potsdam Institute for Climate Impact Research. First, rotated s-mode Principal Component Analyses (PCA) are applied in order to show coherent regions of SST-variability. The resulting time coefficients are analysed by Canonical Correlation Analyses (CCA) in order to investigate the influence of the Atlantic Ocean SSTs on the precipitation of southern Africa. Additional CCAs show possible links of tropical SSTs between the Atlantic, Indian and Pacific Ocean basins. A useful BN-Index is described by the SST-PC time coefficients and compared to different SST indices. The normalized values of this index are used for composite analyses. The results confirm that BNs are generated by SLP-changes above the west-central equatorial Atlantic and show anomalously high SSTs in the Benguela Current and high coastal precipitation values. However, the CCA results clearly reveal that each BN has its own characteristic according to the amount of coastal precipitation. This makes BN forecasts difficult; additionally, regarding time series analyses, spectral and Wavelet

  10. Late Quaternary paleomagnetic secular variation recorded in deep-sea sediments from the Demerara Rise, equatorial west Atlantic Ocean

    Science.gov (United States)

    Lund, Steve; Oppo, Delia; Curry, William

    2017-11-01

    We have carried out a paleomagnetic/rock magnetic study of two gravity cores and two multicores from the Demerara Rise (∼8°N), adjacent to NE South America. The magnetic measurements indicate that there is a stable natural remanent magnetization (NRM) carried primarily by detrital magnetite/titanomagnetite that preserves the local pattern of paleomagnetic secular variation (PSV). The two gravity cores have consistent patterns of directional variability. The rock magnetic intensities in both gravity cores vary by less than a factor of three. Relative paleointensity estimates have been derived by normalizing the NRM to Chi, ARM, and SIRM. Both gravity cores show the same pattern of relative paleointensity variability. 27 calibrated radiocarbon dates from our studied gravity cores and one additional piston core (Huang et al., 2014) have been used to build chronologies for the two gravity cores. Core 25GGC has bulk sedimentation rates varying from 18 to 22 cm/ky and contains a PSV record for the last 19 ka; core 9GGC has bulk sedimentation rates of 9-17 cm/ky and contains a PSV record for the last 28 ka. There are no other published, good-quality, well-dated full-vector PSV records within 4000 km of the sites, a region which constitutes almost 20% of the Earth's surface area. Our relative paleointensity records are consistent with other global records under the assumption of field intensity being largely a global-scale process. We have compared our directional PSV data statistically with eight other good-quality, well-dated low-latitude PSV records. Our statistical analysis shows that our Demerara Rise directional PSV records are consistent with those other studies and that the Late Quaternary Equatorial field variability is significantly lower than much longer-duration (780 ka to 5 Ma) variability.

  11. Food habits of the broad nose skate, Bathyraja brachyurops (Chondrichthyes, Rajidae, in the south-west Atlantic

    Directory of Open Access Journals (Sweden)

    Mauro Belleggia

    2008-12-01

    Full Text Available Food habits of Bathyraja brachyurops were studied based on stomach content analyses of 346 specimens collected from research cruises carried out from 2003 to 2005 on the Argentinean continental shelf (36ºS-55ºS. A total of 265 stomachs (76.6% contained food, and thirty-five taxonomic levels of prey were identified. The most important prey were fishes followed by isopods. Trophic level analysis revealed that B. brachyurops is a tertiary consumer throughout its life history. There were no differences between sexes and regions in the diet composition, but dietary shifts with ontogeny were found. The Levins’ standardized index indicated wider niche breadth for small skates, whereas larger skate specimens showed a narrow niche breadth with a specialization in fishes.

  12. Feeding ecology of Bathyraja macloviana (Rajiformes, Arhynchobatidae: a polychaete-feeding skate from the South-west Atlantic

    Directory of Open Access Journals (Sweden)

    Ezequiel Mabragaña

    2005-09-01

    Full Text Available The present paper analyses the diet, feeding strategy and niche width of B. macloviana in a sector of the Argentinean Continental Shelf (ACS. Individuals (n = 147 were collected from 43 sampling stations in late summer and autumn 2001. Thirty one alimentary items in the gut contents were found, with a clear dominance of polychaetes. Crustaceans were secondary alimentary items. The polychaete Travisia kerguelensis was the main food item ingested, followed by Nepthyidae, Sabellidae and Lumbrineridae, while Gammaridae and Cirolanidae were the main items among crustaceans. The niche width and feeding strategy displayed by B. macloviana support the specialisation towards polychaetes throughout this study. Slow motile and infaunal species constitute major preys. The results suggest that this skate actively selects worms, reflecting, in some sense, the composition of the polychaete assemblage, and allowing a low dietary overlap with other sympatric skates of the ACS.

  13. Molecular identification of cetaceans from the West Atlantic using the E3-I5 region of COI.

    Science.gov (United States)

    Falcão, L H O; Campos, A S; Freitas, J E P; Furtado-Neto, M A A; Faria, V V

    2017-04-20

    Molecular identification is very useful in cases where morphology-based species identification is not possible. Examples for its application in cetaceans include the identification of carcasses of stranded animals in advanced state of decomposition and body parts that are illegally traded. One DNA region that is often used for molecular identification is the Folmer region of the mitochondrial gene cytochrome c oxidase subunit I (COI) (locus 48 to 705 bp). This locus has been used for the identification of several animal species, including whales and dolphins. The goal of the present study was to evaluate the usefulness of another region of COI, the E3-I5 (locus 685 to locus 1179; 495 bp) as a marker for identification of cetaceans from northeastern Canada and northeastern Brazil. The identification markers were successfully obtained for seven cetacean species after performing percent identity and Basic Local Alignment Search Tool analyses. The obtained markers are now publicly available and are useful for the identification of the endangered blue whale (Balaenoptera musculus), common minke whale (B. acutorostrata), vulnerable sperm whale (Physeter macrocephalus), harbor porpoise (Phocoena phocoena), common bottlenose dolphin (Tursiops truncatus), Guiana dolphin (Sotalia guianensis), and melon-headed whale (Peponocephala electra).

  14. Larvae and adults of Hysterothylacium aduncum (Rudolphi, 1802) (Nematoda: Anisakidae) in fishes and crustaceans in the south west Atlantic.

    Science.gov (United States)

    Navone, G T; Sardella, N H; Timi, J T

    1998-06-01

    Hysterothylacium aduncum (Rudolphi, 1802) is reported from five fishes and one invertebrate species. Third-stage larvae were found in the crustacean Themisto gaudichaudii and in mesenteries of the fishes Engraulis anchoita and Merluccius hubbsi; fourth-stage larvae were recovered from the digestive tract of M. hubbsi and Scomber japonicus and adult specimens were obtained from the stomach and intestine of M. hubbsi, S. japonicus, Genypterus blacodes and Genypterus brasiliensis. Nematodes are described, measured and illustrated. Parasitic prevalence, mean intensity and range were calculated in relation to different geographic zones, from the Argentinean-Uruguayan Common Fishing Zone to Patagonic areas. An increase of parasitism from the northern areas southwards was observed. The life-cycle of H. aduncum, involving the host species considered, is also postulated.

  15. Paleoceanography. Onset of Mediterranean outflow into the North Atlantic.

    Science.gov (United States)

    Hernández-Molina, F Javier; Stow, Dorrik A V; Alvarez-Zarikian, Carlos A; Acton, Gary; Bahr, André; Balestra, Barbara; Ducassou, Emmanuelle; Flood, Roger; Flores, José-Abel; Furota, Satoshi; Grunert, Patrick; Hodell, David; Jimenez-Espejo, Francisco; Kim, Jin Kyoung; Krissek, Lawrence; Kuroda, Junichiro; Li, Baohua; Llave, Estefania; Lofi, Johanna; Lourens, Lucas; Miller, Madeline; Nanayama, Futoshi; Nishida, Naohisa; Richter, Carl; Roque, Cristina; Pereira, Hélder; Sanchez Goñi, Maria Fernanda; Sierro, Francisco J; Singh, Arun Deo; Sloss, Craig; Takashimizu, Yasuhiro; Tzanova, Alexandrina; Voelker, Antje; Williams, Trevor; Xuan, Chuang

    2014-06-13

    Sediments cored along the southwestern Iberian margin during Integrated Ocean Drilling Program Expedition 339 provide constraints on Mediterranean Outflow Water (MOW) circulation patterns from the Pliocene epoch to the present day. After the Strait of Gibraltar opened (5.33 million years ago), a limited volume of MOW entered the Atlantic. Depositional hiatuses indicate erosion by bottom currents related to higher volumes of MOW circulating into the North Atlantic, beginning in the late Pliocene. The hiatuses coincide with regional tectonic events and changes in global thermohaline circulation (THC). This suggests that MOW influenced Atlantic Meridional Overturning Circulation (AMOC), THC, and climatic shifts by contributing a component of warm, saline water to northern latitudes while in turn being influenced by plate tectonics. Copyright © 2014, American Association for the Advancement of Science.

  16. Atlantic Meridional Overturning Circulation slowdown cooled the subtropical ocean.

    Science.gov (United States)

    Cunningham, Stuart A; Roberts, Christopher D; Frajka-Williams, Eleanor; Johns, William E; Hobbs, Will; Palmer, Matthew D; Rayner, Darren; Smeed, David A; McCarthy, Gerard

    2013-12-16

    [1] Observations show that the upper 2 km of the subtropical North Atlantic Ocean cooled throughout 2010 and remained cold until at least December 2011. We show that these cold anomalies are partly driven by anomalous air-sea exchange during the cold winters of 2009/2010 and 2010/2011 and, more surprisingly, by extreme interannual variability in the ocean's northward heat transport at 26.5°N. This cooling driven by the ocean's meridional heat transport affects deeper layers isolated from the atmosphere on annual timescales and water that is entrained into the winter mixed layer thus lowering winter sea surface temperatures. Here we connect, for the first time, variability in the northward heat transport carried by the Atlantic Meridional Overturning Circulation to widespread sustained cooling of the subtropical North Atlantic, challenging the prevailing view that the ocean plays a passive role in the coupled ocean-atmosphere system on monthly-to-seasonal timescales.

  17. 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.

  18. 78 FR 72070 - Notice of Availability of Record of Decision for Atlantic Fleet Training and Testing

    Science.gov (United States)

    2013-12-02

    ... Atlantic Fleet Training and Testing AGENCY: Department of the Navy, DoD. ACTION: Notice. SUMMARY: The... testing activities in the Atlantic Fleet study area as described in Alternative 2 for the proposed action... Impact Statement for Atlantic Fleet Training and Testing, dated August 2013 and supporting documents...

  19. 78 FR 71529 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; 2013 Commercial Accountability...

    Science.gov (United States)

    2013-11-29

    .... 130312235-3658-02] RIN 0648-XC982 Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; 2013 Commercial Accountability Measure and Closure for South Atlantic Red Porgy AGENCY: National Marine Fisheries...: The snapper-grouper fishery of the South Atlantic includes red porgy and is managed under the Fishery...

  20. 77 FR 52259 - Atlantic Highly Migratory Species; Lifting Trade Restrictive Measures

    Science.gov (United States)

    2012-08-29

    ... prohibit imports of Atlantic bigeye tuna and its products from Bolivia and Georgia. Specifically... Parties to lift import prohibitions on Atlantic bigeye tuna from Bolivia and Georgia as soon as possible... to remove the Atlantic bigeye tuna import prohibitions from Bolivia and Georgia (77 FR 38030), and...