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

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulations; Key West World Championship, Atlantic Ocean; Key West, FL AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast... Key West, Florida during the Key West World Championship, a series of high-speed boat races. The...

  2. Organic complexation of iron in the West Atlantic Ocean

    NARCIS (Netherlands)

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

    2015-01-01

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

  3. Atlantic forcing of persistent drought in West Africa.

    Science.gov (United States)

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

    2009-04-17

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

  4. Modeling the impact of changes in Atlantic sea surface temperature on the climate of West Africa

    Science.gov (United States)

    Adeniyi, Mojisola O.

    2016-08-01

    This study assesses the impacts of warming/cooling of the Atlantic sea surface temperature (SST) on the climate of West Africa using Version 4.4 of Regional Climate Model (RegCM4.4) of International Center for Theoretical Physics, Trieste, Italy. The 1-2 K cooling and warming of the Atlantic SST both result in tripole temperature and precipitation change structure, having a northwest-southeast orientation over West Africa. Findings reveal that the responses of precipitation and temperature to the Atlantic SST cooling are opposite to those for the Atlantic SST warming and these responses intensify with increased warming/cooling of the Atlantic SST. The structure of the change in climate is attributed to the response of atmospheric/soil moisture gradient and orientation of orography in West Africa.

  5. 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.)

  6. 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 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.

  7. 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

  8. 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...... nematode species regarding prevalence of infection and mean infection intensity was evident, and there was no relationship between fish condition and the intensity of nematode infections. Standardised for size, capelin-eating cod were in better condition and more heavily infected than fish subsisting...

  9. Genetic and morphometric differences between yellowtail snapper (Ocyurus chrysurus, Lutjanidae populations of the tropical West Atlantic

    Directory of Open Access Journals (Sweden)

    Anderson V. Vasconcellos

    2008-01-01

    Full Text Available Populations of Ocyurus chrysurus were compared genetically and morphometrically along the West Atlantic coast to test the null hypothesis of population homogeneity in the area. Brazilian populations were found to be differentiated in shape (canonical variates analysis; F[48,515] = 10.84, p < 0.0001. Analyses of mitochondrial DNA sequences (663 bp of the control region did not show any differences between Brazilian populations but could detect differences between Brazilian and Caribbean (Belize populations. The samples from Pernambuco differed significantly from the other Brazilian populations in allozyme frequencies (11 loci; F ST = 0.167; p < 0.05, but this may have resulted from the small number of samples analysed for that population. Sequence variation of Belize samples departed from neutral expectations (Fu's FS = -8.88; p < 0.001. A mismatch distribution analysis points to an ancient population expansion in that area. We conclude that the genetic data do not allow the rejection of the null hypothesis of panmixia for Brazilian yellowtail snapper populations which should be treated as a single genetic stock, with a latitudinal gradient on their morphology which probably results from phenotypic plasticity. On the other hand, there is a severe restriction to gene flow between O. chrysurus populations from the Caribbean and from the southwestern Atlantic.

  10. Stress pattern in Portugal mainland and the adjacent Atlantic region, West Iberia

    Science.gov (United States)

    Ribeiro, A.; Cabral, J.; Baptista, R.; Matias, L.

    1996-06-01

    The Portuguese mainland territory is located close to the Azores-Gibraltar plate boundary, in a tectonic setting responsible for significant neotectonic and seismic activities. However, few data concerning the present regional lithospheric stress field were available, as testified by recently published maps of stress indicators for the Europe and Mediterranean regions. One of the authors already presented a synthesis on this subject [Cabral, 1993], where geological and geophysical stress indicators were considered. In this paper we introduce new information, mainly a considerable amount of borehole breakout data. The updated data set comprises 32 reliable stress indicators showing a mean azimuth of 145° (standard deviation 21°) for the maximum horizontal stress direction (SHmax). On the average, the geological data are rotated clockwise and the focal mechanism data deviated anticlockwise to that azimuth, while the borehole elongation results are consistent with the mean SHmax trend. These differences in stress trend suggest a regional progressive rotation of the SHmax direction from NNW-SSE to WNW-ESE since the upper Pliocene. To estimate stress trajectories, new and published stress indicators in the adjacent Atlantic area and northern Africa were also investigated, showing a very uniform NW-SE SHmax trend in west Iberia. A high level of horizontal compressive stress acting oblique to the western Portuguese continental margin is inferred and interpreted in view of a proposed regional geodynamical model, of activation of this passive margin, with the nucleation of a subduction zone in the Atlantic SW of Iberia, at the Gorringe submarine bank, which is propagating northward along the base of the continental slope, at the transition between thinned and normal continental crust.

  11. 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

    2016-12-01

    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.

  12. Mixed-stock analysis in green turtles Chelonia mydas: mtDNA decipher current connections among west Atlantic populations.

    Science.gov (United States)

    Costa Jordao, Juliana; Bondioli, Ana Cristina Vigliar; Almeida-Toledo, Lurdes Foresti de; Bilo, Karin; Berzins, Rachel; Le Maho, Yvon; Chevallier, Damien; de Thoisy, Benoit

    2017-03-01

    The green turtle Chelonia mydas undertakes wide-ranging migrations between feeding and nesting sites, resulting in mixing and isolation of genetic stocks. We used mtDNA control region to characterize the genetic composition, population structure, and natal origins of C. mydas in the West Atlantic Ocean, at one feeding ground (State of Rio de Janeiro, Brazil), and three Caribbean nesting grounds (French Guiana, Guadeloupe, and Suriname). The feeding ground presented considerable frequency of common haplotypes from the South Atlantic, whereas the nesting sites presented a major contribution of the most common haplotype from the Caribbean. MSA revealed multiple origins of individuals at the feeding ground, notably from Ascension Island, Guinea Bissau, and French Guiana. This study enables a better understanding of the dispersion patterns and highlights the importance of connecting both nesting and feeding areas. Effective conservation initiatives need to encompass these ecologically and geographically distinct sites as well as those corridors connecting them.

  13. 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...... 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...

  14. 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.

  15. West African paleoclimates during the last climatic cycle inferred from an Atlantic deep-sea pollen record

    Science.gov (United States)

    Lezine, Anne-Marie

    1991-05-01

    Pollen studies of marine sediments from Atlantic deep-sea core V22-196 (13°50' N-18°57' W; 3728-m water depth) are used to reconstruct paleoclimates of north tropical west Africa since 140,000 yr B.P. High concentration of pollen, mainly from Saharan and arid littoral zones suggests a strengthened tradewind circulation since ca. 60,000 yr B.P. that became even stronger after 40,000 yr B.P. and reached a maximum 17,000 yr B.P. Periods of eolian transport of pollen to the Atlantic occurred about 94,000 and 105,000 yr B.P. and during Termination II. Conversely, high relative values of pollen from Sudanian and Guinean zones and from Mangrove and freshwater vegetation, coincident with maxima of dinocyst concentration, are interpreted as reflecting both strong fluvial inputs and the expansion of humid vegetation on the adjacent continent during wet periods dated between 140,000 and 118,000, 105,000 and 96,000, 92,000 and 73,000, 52,000 and 44,000 yr B.P. and 12,000 yr B.P. and the Holocene. The strong correlation of these results from the eastern tropical Atlantic with those from the Arabian Sea corroborates fluctuations of monsoon climate.

  16. Multiple 'Stable' States of Antarctic Intermediate Water: A Study from the Subantarctic South-West Atlantic.

    Science.gov (United States)

    Roberts, J.; Hodell, D. A.; Peck, V. L.; Kender, S.

    2014-12-01

    Modelling studies suggest that density changes in Antarctic Intermediate Water (AAIW) played a significant role in the reorganisation of Atlantic Meridional Overturning Circulation over the last glacial period. From its principal site of formation in the SE Pacific, a significant proportion of AAIW is entrained in the Antarctic circumpolar current and enters the Atlantic through Drake Passage. Air-sea interaction within the subAntarctic SW Atlantic modifies this AAIW further, producing a cooler and fresher Atlantic end member of AAIW. Our core site is located where this branch of AAIW subducts and travels northwards along the western margin of the Atlantic basin. We present the first high-resolution, multi-proxy study of AAIW in the sub-Antarctic SW Atlantic over the last 140 kyrs. Here, we focus on the temperature and salinity records over the last two glacial terminations and at the onset of the last glaciation. We use a combination of benthic stable isotopes and elemental ratios (Mg/Ca) on the shallow infaunal species Uvigerina peregrina to reconstruct AAIW temperature and salinity. Our records suggest that AAIW temperature both increased and decreased in a step-wise manner over the last 120 kyrs hinting at 3 'stable' states for AAIW through the last glacial cycle (see shaded areas within figure). Another common feature is a transient interval of apparently warm, saline AAIW observed at the onset of both glacial terminations - could this be evidence of the 'deep, salty blob' or of increased outflow of Pacific surface waters? We identify some fundamental differences between termination I and termination II; AAIW appears to have been markedly warmer during MIS6 than at the LGM. Furthermore, the glacial-interglacial potential density difference is much greater over termination I than termination II.

  17. 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

  18. 77 FR 75853 - Safety Zone; Bone Island Triathlon, Atlantic Ocean; Key West, FL

    Science.gov (United States)

    2012-12-26

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Bone Island Triathlon, Atlantic Ocean; Key... Island Triathlon on Saturday, January 12, 2013. The safety zone is necessary to provide for the safety of..., Questor Multisport, LLC is hosting the Bone Island Triathlon. The event will be held on the waters of...

  19. 78 FR 70901 - Safety Zone; Bone Island Triathlon, Atlantic Ocean; Key West, FL

    Science.gov (United States)

    2013-11-27

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Bone Island Triathlon, Atlantic Ocean; Key..., during the Bone Island Triathlon on Saturday, January 25, 2014. The safety zone is necessary to provide... Multisport, LLC. is hosting the Bone Island Triathlon. The event will be held on the waters of the...

  20. West Africa Extreme Rainfall Events and Large-Scale Ocean Surface and Atmospheric Conditions in the Tropical Atlantic

    Directory of Open Access Journals (Sweden)

    S. Ta

    2016-01-01

    Full Text Available Based on daily precipitation from the Global Precipitation Climatology Project (GPCP data during April–October of the 1997–2014 period, the daily extreme rainfall trends and variability over West Africa are characterized using 90th-percentile threshold at each grid point. The contribution of the extreme rainfall amount reaches ~50–90% in the northern region while it is ~30–50% in the south. The yearly cumulated extreme rainfall amount indicates significant and negative trends in the 6°N–12°N; 6°N–12°N; 17°W–10°W and 4°N–7°N; 4°N–7°N; 6°E–10°E 4°N–7°N; 6°E–10°E 4°N–7°N; 6°E–10°E domains, while the number of days exhibits nonsignificant trends over West Africa. The empirical orthogonal functions performed on the standardized anomalies show four variability modes that include all West Africa with a focus on the Sahelian region, the eastern region including the south of Nigeria, the western part including Guinea, Sierra Leone, Liberia, and Guinea-Bissau, and finally a small region at the coast of Ghana and Togo. These four modes are influenced differently by the large-scale ocean surface and atmospheric conditions in the tropical Atlantic. The results are applicable in planning the risks associated with these climate hazards, particularly on water resource management and civil defense.

  1. 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

  2. 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...

  3. Secondary microseism generation mechanisms and microseism derived ocean wave parameters, NE Atlantic, West of Ireland.

    Science.gov (United States)

    Donne, S. E.; Bean, C. J.; Lokmer, I.; Nicolau, M.; O'Neill, M.

    2014-12-01

    Ocean waves, driven by atmospheric processes, generate faint continuous Earth vibrations known as microseisms (Bromirski, 1999). Under certain conditions, ocean waves travelling in opposite directions may interact with one another producing a partial or full standing wave. This wave-wave interaction produces a pressure profile, unattenuated with depth, which exerts a pressure change at the seafloor, resulting in secondary microseisms in the 0.1-0.33 Hz band. There are clear correlations between microseism amplitude and storm and ocean wave intensity. We aim to determine ocean wave heights in the Northeast Atlantic offshore Ireland at individual buoy locations, using terrestrially recorded microseism signals. Two evolutionary approaches are used: Artificial Neural Networks (ANN) and Grammatical Evolution (GE). These systems learn to interpret particular input patterns and corresponding outputs and expose the often complex underlying relationship between them. They learn by example and are therefore entirely data driven so data selection is extremely important for the success of the methods. An analysis and comparison of the performance of these methods for a five month period in 2013 will be presented showing that ocean wave characteristics may be reconstructed using microseism amplitudes, adopting a purely data driven approach. There are periods during the year when the estimations made from both the GE and ANN are delayed in time by 10 to 20 hours when compared to the target buoy measurements. These delays hold important information about the totality of the conditions needed for microseism generation, an analysis of which will be presented.

  4. A genetic overview of Atlantic coastal populations from Europe and North-West Africa based on a 17 X-STR panel.

    Science.gov (United States)

    Prieto-Fernández, Endika; Díaz-de Usera, Ana; Baeta, Miriam; Núñez, Carolina; Chbel, Faiza; Nadifi, Sellama; Rouault, Karen; Férec, Claude; Hardiman, Orla; Pinheiro, Fátima; de Pancorbo, Marian M

    2017-03-01

    The forensic use of X-STRs requires the creation of allele and haplotype frequency databases in the populations where they are going to be used. Recently, an updated Spanish allele and haplotype frequency database for the new 17 X-STR panel has been created, being the only database available up to now for this new multiplex. In order to broaden the forensic applicability of the 17 X-STR panel, 513 individuals from four different populations located on the Atlantic Coast of Europe and North-West Africa have been studied, i.e. Brittany (France), Ireland, northern Portugal, and Casablanca (Morocco). Allele and haplotype frequency databases, as well as parameters of forensic interest for these populations are presented. The obtained results showed that the 17 X-STR panel constitutes a highly discriminative tool for forensic identification and kinship testing in the studied populations. Furthermore, we aimed to study if these populations located on the Atlantic coast actually share alike allele and haplotype frequency distributions since they have experienced genetic exchanges throughout history. This would allow creating larger forensic databases that include several genetically similar populations for its use in forensic casework. For this purpose, pairwise FST genetic distances between the analyzed populations and others from the Atlantic Coast previously studied with the 17 X-STR panel or the ten coincident markers included in the decaplex of the GHEP-ISFG were estimated. Our results suggest that certain nearby populations located on the European Atlantic coast could have underwent episodes of genetic interchange as they have not shown statistically significant differentiation between them. However, the population of Casablanca showed significant differentiation with the majority of the European populations. Likewise, the autochthonous Basque Country and Brittany populations have shown distinctive allele frequency distributions between them. Therefore, these

  5. 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

    ... Security FR Federal Register NPRM Notice of Proposed Rulemaking A. Regulatory History and Information The... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation; Annual Swim Around Key West... and the Gulf of Mexico surrounding the island of Key West, Florida during the Annual Swim around...

  6. 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)

  7. Field Signatures of the SE-Asian Mega-Tsunami along the West Coast of Thailand Compared to Holocene Paleo-Tsunami from the Atlantic Region

    Science.gov (United States)

    Kelletat, Dieter; Scheffers, Sander R.; Scheffers, Anja

    2007-03-01

    The Andaman-Sumatra Tsunami of Dec. 26, 2004, was by far the largest tsunami catastrophe in human history. An earthquake of 9 to 9.3 on the Richter scale, the extension of waves over more than 5000 km of ocean and run-ups up to 35 m are its key features. These characteristics suggest significant changes in coastal morphology and high sediment transport rates. A field survey along the west coast of Thailand (Phuket Island, Khao Lak region including some Similan Islands, Nang Pha mangrove areas and Phi Phi Don Islands) seven to nine weeks after the tsunami, however, discovered only small changes in coastal morphology and a limited amount of dislocated sediments, restricted to the lower meters of the tsunami waves. This is in striking contrast to many paleo-tsunami's events of the Atlantic region. Explanations for this discrepancy are sought in: a. Mechanics of the earthquake. A rather slow shock impulse on the water masses over the very long earthquake zone, b. Shallow water in the earthquake zone, and c. Bathymetry of the foreshore zone at the impacted sites. Shallow water west of Thailand has diminished wave energy significantly. The differences in geomorphological and sedimentological signatures of this tsunami compared with many paleo-tsunami worldwide makes it unsuitable to be used as a model for old and future tsunami imprints by an event of this extreme energy and extension.

  8. 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...

  9. Intraplate compressional deformation in West-Congo and the Congo basin: related to ridge-puch from the South Atlantic spreading ridge?

    Science.gov (United States)

    Delvaux, Damien; Everaerts, Michel; Kongota Isasi, Elvis; Ganza Bamulezi, Gloire

    2016-04-01

    After the break-up and separation of South America from Africa and the initiation of the South-Atlantic mid-oceanic ridge in the Albian, at about 120 Ma, ridge-push forces started to build-up in the oceanic lithosphere and were transmitted to the adjacent continental plates. This is particularly well expressed in the passive margin and continental interior of Central Africa. According to the relations of Wiens and Stein (1985) between ridge-push forces and basal drag in function of the lithospheric age of oceanic plates, the deviatoric stress reaches a compressional maximum between 50 and 100, Ma after the initiation of the spreading ridge, so broadly corresponding to the Paleocene in this case (~70-20 Ma). Earthquake focal mechanism data show that the West-Congo margin and a large part of the Congo basin are still currently under compressional stresses with an horizontal compression parallel to the direction of the active transform fracture zones. We studied the fracture network along the Congo River in Kinshasa and Brazzaville which affect Cambrian sandstones and probably also the late Cretaceous-Paleocene sediments. Their brittle tectonic evolution is compatible with the buildup of ridge-push forces related to the South-Atlantic opening. Further inland, low-angle reverse faults are found affecting Jurassic to Middle Cretaceous cores from the Samba borehole in the Congo basin and strike-slip movements are recorded as a second brittle phase in the Permian cores of the Dekese well, at the southern margin of the Congo basin. An analysis of the topography and river network of the Congo basin show the development of low-amplitude (50-100 m) long wavelengths (100-300 km) undulations that can be interpreted as lithospheric buckling in response to the compressional intraplate stress field generated by the Mid-Atlantic ridge-push. Wiens, D.A., Stein, S., 1985. Implications of oceanic intraplate seismicity for plate stresses, driving forces and theology. Tectonophysics

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

    Science.gov (United States)

    Amado-Filho, Gilberto M; Moura, Rodrigo L; Bastos, Alex C; Salgado, Leonardo T; Sumida, Paulo Y; Guth, Arthur Z; Francini-Filho, Ronaldo B; Pereira-Filho, Guilherme H; Abrantes, Douglas P; Brasileiro, Poliana S; Bahia, Ricardo G; Leal, Rachel N; Kaufman, Les; Kleypas, Joanie A; Farina, Marcos; Thompson, Fabiano L

    2012-01-01

    Rhodoliths are nodules of non-geniculate coralline algae that occur in shallow waters (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.

  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. Large differences in aerosol optical properties over the north-west Atlantic Ocean during the TCAP field campaign

    Science.gov (United States)

    Chand, D.; Berg, L. K.; Comstock, J. M.; Fast, J. D.; Flynn, C. J.; Hubbe, J. M.; Kassianov, E.; Mei, F.; Pekour, M. S.; Schmid, B.; Sedlacek, A. J., III; Tomlinson, J. M.; Shilling, J. E.; Wilson, J. M.; Zelenyuk, A.; Berkowitz, C. M.

    2014-12-01

    Aerosol radiative forcing is an important parameter in the Earth's radiation budget and can be an important driver of atmospheric circulation and the hydrological cycle. Accurate estimation of aerosol radiative forcing requires measurement of both the extensive and intensive optical properties of aerosols. While the intensive optical properties are independent of aerosol mass or number, they are critical inputs when calculating radiative forcing with applications to climate research, satellite remote sensing and model validations. The key aerosol intensive properties that need to be evaluated include single scattering albedo (SSA), the angstrom exponent, the asymmetry parameter, the radiative forcing efficiency, and the hygroscopic scattering factor. We report here on values of these variables over the Cape Cod and nearby northwest Atlantic Ocean during the Two Column Aerosol Project (TCAP). The average SSA shows a distinct profile having higher SSA values below the top of well-mixed residual layer (RL) and lower SSA above it. Aerosol in the free troposphere (FT) were found to have less spectral dependence in their optical properties, lower back scatter fraction and higher hygroscopic growth relative to aerosols found in the RL. Analysis of individual particle composition suggests that that ratio of aged to fresh aerosol numbers in the FT is 70% higher compared to aerosols measured in the RL, and that smoke from biomass burning contributed ~10% to this number. Single particle analysis also reveals that the fraction and variability of coated black carbon (BC) aerosol is higher in the FT relative to that measured in the residual layer. The daily radiative forcing efficiency of these aerosols in the FT is factor 2 higher than below RL. Seven years (2007-2013) of CALIPSO satellite observations show that the mean altitude of the top of smoke layers (~3.3 km) consistent with these in situ observations from TCAP. Overall, the long term CALIPSO observations characterizes

  13. The influence of biomass burning and transport on tropospheric composition over the tropical Atlantic Ocean and Equatorial Africa during the West African monsoon in 2006

    Directory of Open Access Journals (Sweden)

    J. E. Williams

    2010-10-01

    Full Text Available Biomass burning (BB in southern Africa is the largest emission source of CO and O3 precursors within Africa during the West African Monsoon (WAM between June and August. The long range transport and chemical processing of such emissions thus has the potential to exert a dominant influence on the composition of the tropical troposphere over Equatorial Africa (EA and the Tropical Atlantic Ocean (TAO. We have performed simulations using a three-dimensional global chemistry-transport model (CTM to quantify the effect that continental transport of such BB plumes has on the EA region. BB emissions from southern Africa were found to exert a significant influence over the TAO and EA between 10° S–20° N. The maximum concentrations in CO and O3 occur between 0–5° S near the position of the African Easterly Jet – South as placed by the European Centre for Medium range Weather Forecasts (ECMWF meteorological analysis data. By comparing co-located model output with in-situ measurements we show that the CTM fails to capture the tropospheric profile of CO in southern Africa near the main source region of the BB emissions, as well as the "extreme" concentrations of both CO and O3 seen between 600–700 hPa over EA around 6° N. For more northerly locations the model exhibits high background concentrations in both CO and O3 related to BB emissions from southern Africa. By altering both the temporal resolution and the vertical distribution of BB emissions in the model we show that changes in temporal resolution have the largest influence on the transport of trace gases near the source regions, EA, and in the outflow towards the west of Central Africa. Using a set of trajectory calculations we show that the performance of the CTM is heavily constrained by the ECMWF meteorological fields used to drive the CTM, which transport biomass burning plumes from southern Africa into the lower troposphere of the TAO rather

  14. West Africa

    Science.gov (United States)

    2002-01-01

    With its vast expanses of sand, framed by mountain ranges and exposed rock, northwestern Africa makes a pretty picture when viewed from above. This image was acquired by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra spacecraft. The Canary Islands can be seen on the left side of the image just off Africa's Atlantic shore. The light brown expanse running through the northern two thirds of the image is the Sahara Desert. The desert runs up against the dark brown Haut Atlas mountain range of Morocco in the northwest, the Atlantic Ocean to the west and the semi-arid (light brown pixels) Sahelian region in the South. The Sahara, however, isn't staying put. Since the 1960s, the desert has been expanding into the Sahelian region at a rate of up to 6 kilometers per year. In the 1980s this desert expansion, combined with over cultivation of the Sahel, caused a major famine across west Africa. Over the summer months, strong winds pick up sands from the Sahara and blow them across the Atlantic as far west as North America, causing air pollution in Miami and damaging coral reefs in the Bahamas and the Florida Keys. The white outlines on the map represent country borders. Starting at the top-most portion of the map and working clockwise, the countries shown are Morocco, Western Sahara, Mauritania, Senegal, Mali, Burkina Fasso, Nigeria, Mali (again), and Algeria. Image by Reto Stockli, Robert Simmon, and Brian Montgomery, NASA Earth Observatory, based on data from MODIS

  15. Coupled marine productivity and salinity and West African monsoon variability over the last 30,000 years in the eastern equatorial Atlantic Ocean

    Science.gov (United States)

    Marret, F.; Kim, S.-Y.; Scourse, J.; Kennedy, H.

    2009-04-01

    Marine cores collected off west equatorial Africa have highlighted transfer of terrigenous material in the close ocean that have had a deep influence on the marine productivity for the last 30,000 years. The strength of the West African Monsoon has varied though time, from weak during glacial periods to strong during interglacials. In consequence, the amount of precipitation on the continent had drastic effect on the vegetation cover and soil erosion. Studies of marine cores have enabled the observation of changes in vegetation cover, from extended equatorial rainforest to expansion of savannahs. In association with open grassland association, soil is open to erosion, although precipitation is less; conversely, during periods of extended rainforest in a context of strong monsoon, soil erosion is minimised to the presence of trees. In both cases, terrigenous material is flushed out to the adjacent marine domain and has a profound influence on the marine biota. Three marine cores were studied from a north south transect, from Cameroon to Angola (off Sanaga, off Ogouée, and off Congo rivers), for their palynomorph contents. All cores contain a robust chronology based on radiocarbon dates and two have stable isotope data, allowing comparison. Dinoflagellate cysts were studied for retracing sea-surface conditions such as temperature, salinity and productivity whereas pollen were used to assess changes in the vegetation on the close continent for the last 30,000 years (1). A number of pollen records from terrestrial sequences from equatorial central Africa document the dynamics of the lowland rainforest and savannah in relation to climatic changes during the Holocene. Prior to the Holocene, continental records are scarce in this vast region and/or only allow reconstruction of the local vegetation. In our records, terrestrial proxies (pollen, spores, and charred grass cuticles) signal changes in the expansion/regression of the lowland rainforest which we relate to the

  16. 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

  17. 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

  18. 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.)

  19. Transferrin gene polymorphisms and population genetic studies of Atlantic cod (Gadus morhua)

    Institute of Scientific and Technical Information of China (English)

    Berhan Asmamaw

    2016-01-01

    Objective:To detect single nucleotide polymorphisms (SNPs) in the cod transferrin gene by comparing the sequences from Norwegian (North East Atlantic Ocean) and Canadian (North West Atlantic Ocean) specimen, and to quantify the genetic variation and differentiation in East and West Atlantic cod populations. Methods:cDNA sequences between individuals of Canadian (North West Atlantic Ocean) and Norwegian (North East Atlantic Ocean) origin were aligned. Allele frequencies of theSNPs were used to discriminate the different Atlantic cod populations in West/East Atlantic Ocean, and the Baltic Sea. Results: The sequence alignment detected19SNPs, of which 18 of them resulted in amino acid changes in the transferrin protein. Nonsynonymous to synonymous site substitution ratio (dn/ds) was by far greater than 1 providing an evidence for the existence of positive selection. The West Atlantic cod populations showed high values of heterozygosity and the Baltic populations were found to be inbred. Conclusions: This study identified and indicated transferrin gene polymorphisms that can be used for population differentiations.

  20. Kinematics of the South Atlantic rift

    Directory of Open Access Journals (Sweden)

    C. Heine

    2013-01-01

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

  1. 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,...

  2. 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...

  3. GUIDE POUR L'INTERPRÉTATION DES ÉCAILLES ET L'ESTIMATION DE L'ÂGE CHEZ LES ALOSES (ALOSA SPP. DE LA FAÇADE ATLANTIQUE-EST ET DE LA MÉDITERRANÉE-OUEST. A GUIDE TO SCALE INTERPRETATION AND AGE ESTIMATION FOR THE EAST-ATLANTIC AND WEST-MEDITERRANEAN SHADS (ALOSA SPP..

    Directory of Open Access Journals (Sweden)

    BAGLINIÈRE J. L.

    2008-05-01

    Full Text Available L'objectif général de ce guide est de fournir un manuel d'utilisation et d'interprétation des écailles pour l'estimation de l'âge chez les aloses de l'Atlantique-Est et de Méditerranée-Ouest (Grande Alose, Alose feinte atlantique et méditerranéenne. Après un présentation rapide des espèces, populations et fleuves analysés, les écailles d'aloses et les méthodes de récolte, de préparation et de montage les concernant sont décrites en détail. Des définitions et un système de notation de l'âge standards sont donnés. La grande majorité des difficultés rencontrées pour l'interprétation des écailles sont analysées en proposant des solutions et en donnant certaines recommandations. L'ensemble de ce guide est largement illustré à l'aide d'exemples d'écailles typiques et atypiques choisis chez tous les taxons des différentes populations étudiées. The general objective of this guide is to provide a practical manual for interpreting scales and the estimation of age of Alosa from the East Atlantic and West-Mediterranean (Allis shad, Atlantic and Mediterranean shad. Following a brief presentation of the species, populations and rivers studied, the scales, sampling methods and their preparation for reading are described in detail. Definitions and a standard system of notating age are given. The majority of the difficulties encountered in the interpretation of scales are analysed, solutions proposed and some recommendations given. The whole guide is largely illustrative using examples of typical and atypical scales from the various taxons of the different populations studied.

  4. Frontal structures in the West Spitsbergen Current margins

    Directory of Open Access Journals (Sweden)

    W. Walczowski

    2013-07-01

    Full Text Available The structures of the hydrographic fronts separating the Atlantic origin waters from ambient waters in the northern Nordic Seas are discussed. Flows of the western and eastern branches of the West Spitsbergen Current create the Atlantic domain borders and maintain these fronts. The work is based on previous research and on investigations in the project DAMOCLES (Developing Arctic Modeling and Observational Capabilities for Long-term Environmental Studies. Most of the observational data were collected during the R/V Oceania cruises. The main focus of the paper is put on the western border of the Atlantic domain – the Arctic Front, along- and transfrontal transports, the front instability and variability. The baroclinic instability and advection of baroclinic eddies which occurs due to this instability were found as the main transfrontal transport processes. Most of the Atlantic Water transported by the western branch recirculates west and southward. The eastern branch of the West Spitsbergen Current provides most of the Atlantic Water entering the Arctic Ocean. Both processes are very important for the Arctic and global Thermohaline Circulation.

  5. Walruses in West Greenland: Where do they belong?

    DEFF Research Database (Denmark)

    Born, E. W.; Andersen, L. W.; Dietz, R.;

    Historically, Atlantic walruses (Odobenus rosmarus rosmarus) were heavily exploited on their wintering grounds in Central West Greenland (CWG; 67º-71º30´N). Walruses in this area are still exploited and the group is thought to be much below historical population size. However, the demographic...

  6. Implications of isolation and low genetic diversity in peripheral populations of an amphi-Atlantic coral.

    Science.gov (United States)

    Nunes, F; Norris, R D; Knowlton, N

    2009-10-01

    Limited dispersal and connectivity in marine organisms can have negative fitness effects in populations that are small and isolated, but reduced genetic exchange may also promote the potential for local adaptation. Here, we compare the levels of genetic diversity and connectivity in the coral Montastraea cavernosa among both central and peripheral populations throughout its range in the Atlantic. Genetic data from one mitochondrial and two nuclear loci in 191 individuals show that M. cavernosa is subdivided into three genetically distinct regions in the Atlantic: Caribbean-North Atlantic, Western South Atlantic (Brazil) and Eastern Tropical Atlantic (West Africa). Within each region, populations have similar allele frequencies and levels of genetic diversity; indeed, no significant differentiation was found between populations separated by as much as 3000 km, suggesting that this coral species has the ability to disperse over large distances. Gene flow within regions does not, however, translate into connectivity across the entire Atlantic. Instead, substantial differences in allele frequencies across regions suggest that genetic exchange is infrequent between the Caribbean, Brazil and West Africa. Furthermore, markedly lower levels of genetic diversity are observed in the Brazilian and West African populations. Genetic diversity and connectivity may contribute to the resilience of a coral population to disturbance. Isolated peripheral populations may be more vulnerable to human impacts, disease or climate change relative to those in the genetically diverse Caribbean-North Atlantic region.

  7. Life cycle assessment of Icelandic Atlantic salmon Aquaculture

    OpenAIRE

    2011-01-01

    This study analysed the environmental impacts of Atlantic salmon (Salmo salar) farmed in sea cages in Tálknafjörður, North West of Iceland. Methodologically the study was based on Life Cycle Assessment (LCA), and the functional unit was 1 metric tonne of the whole Atlantic salmon produced in sea cage system and delivered to a processing plant in Patreksfjörður. The life cycle model included the feed production (including feed raw materials production), hatchery, sea-cage farm, faming equipmen...

  8. Recent Decadal Trend in the North Atlantic Wind Energy Resources

    Directory of Open Access Journals (Sweden)

    Chong Wei Zheng

    2017-01-01

    Full Text Available This study presents the climatic trend of the North Atlantic wind energy using cross-calibrated, multiplatform (CCMP wind data for the period 1988–2011. Results show the following. (1 The North Atlantic WPD exhibited a significant increasing trend of 4.45  (W/m2/yr over the past 24 years. (2 The variation in the North Atlantic Ocean WPD shows a noticeable regional difference. More than half of the North Atlantic Ocean has a significantly increasing trend in WPD. The increasing trend in the mid-high latitudes is stronger than that in the low latitudes, and the trend is stronger in the west than in the east. The area with the strongest increasing trend is located along the southern coast of Greenland of 35 (W/m2/yr. (3 There is a noticeable seasonal difference in the variation of WPD. The strongest increasing trend occurs in December-January-February (DJF, followed by September-October-November (SON and March-April-May (MAM, and the weakest occurs in June-July-August (JJA. The increasing trend in different areas is dominated by different seasons. (4 There is no leading or lagging correlation between WPD and the North Atlantic Oscillation (NAO. However, there is a noticeable negative correlation between the Niño3 index and WPD in most of the North Atlantic.

  9. Atlantic Salmon Telemetry Monitoring

    Data.gov (United States)

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

  10. Woman Swims Atlantic

    Institute of Scientific and Technical Information of China (English)

    贾庆文

    2009-01-01

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

  11. Kinematics of the South Atlantic rift

    CERN Document Server

    Heine, Christian; Müller, R Dietmar

    2013-01-01

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

  12. Linkages of Remote Sea Surface Temperatures and Atlantic Tropical Cyclone Activity Mediated by the African Monsoon

    Energy Technology Data Exchange (ETDEWEB)

    Taraphdar, Sourav; Leung, Lai-Yung R.; Hagos, Samson M.

    2015-01-28

    Warm sea surface temperatures (SSTs) in North Atlantic and Mediterranean (NAMED) can influence tropical cyclone (TC) activity in the tropical East Atlantic by modulating summer convection over western Africa. Analysis of 30 years of observations show that the NAMED SST is linked to a strengthening of the Saharan heat low and enhancement of moisture and moist static energy in the lower atmosphere over West Africa, which favors a northward displacement of the monsoonal front. These processes also lead to a northward shift of the African easterly jet that introduces an anomalous positive vorticity from western Africa to the main development region (50W–20E; 10N–20N) of Atlantic TC. By modulating multiple processes associated with the African monsoon, this study demonstrates that warm NAMED SST explains 8% of interannual variability of Atlantic TC frequency. Thus NAME SST may provide useful predictability for Atlantic TC activity on seasonal-to-interannual time scale.

  13. 75 FR 57698 - Atlantic Highly Migratory Species; Atlantic Billfish Management, White Marlin (Kajikia albidus

    Science.gov (United States)

    2010-09-22

    ... western Atlantic Ocean, white marlin and blue marlin from the North Atlantic Ocean, and longbill spearfish from the entire Atlantic Ocean; described objectives for the Atlantic billfish fishery; and established... Conservation of Atlantic Tunas (ICCAT). Currently, Atlantic billfish managed by NMFS include Atlantic...

  14. 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...

  15. Mitochondrial genome of the bullet tuna Auxis rochei from Indo-West Pacific collection provides novel genetic information about two subspecies.

    Science.gov (United States)

    Li, Mingming; Guo, Liang; Zhang, Heng; Yang, Sen; Chen, Xinghan; Lin, Haoran; Meng, Zining

    2016-09-01

    Previously morphological studies supported the division of the bullet tuna into the two subspecies, Auxis rochei rochei and A. rochei eudorax. As a cosmopolitan species, A. rochei rochei ranges in the Indo-West Pacific and Atlantic oceans, while A. rochei eudorax inhabits in eastern Pacific region. Here, we used the HiSeq next-generation sequencing technique to determine the mitochondrial genome (mitogenome) of A. rochei from Indo-West Pacific collection, and then compared our data with mitogenomic sequences of the Atlantic and eastern Pacific retrieved from NCBI database. Results showed the mitogenome of A. rochei from three geographic collections shared the same genes and gene order, similar to typical teleosts. Also, we examined a low level of nucleotide diversity among these mitogenomic sequences. Interestingly, nucleotide diversity of intra-subspecies (Atlantic versus Indo-West) was higher than that of inter-subspecies (Atlantic versus eastern Pacific, Indo-West versus eastern Pacific).

  16. North Atlantic Circulation

    Science.gov (United States)

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

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

  17. West Nile virus

    Science.gov (United States)

    ... West Nile encephalitis or meningitis may lead to brain damage and death. 1 in 10 people with brain inflammation do ... Complications from severe West Nile virus infection include: Brain damage Permanent muscle weakness (sometimes similar to polio ) Death

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

    Science.gov (United States)

    Dacre, H.; Gray, S.

    2009-09-01

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

  19. Indian-atlantic transfer of thermocline water at the agulhas retroflection.

    Science.gov (United States)

    Gordon, A L

    1985-03-01

    During November and December 1983, two anticyclonic eddies were observed west of the Agulhas Retroflection, apparently spawned at the retroflection. The western eddy, centered 300 kilometers southwest of Cape Town, has a winter cooled core encircled by warm Indian Ocean water. Between Cape Town and the "Cape Town Eddy" is a net geostrophic transport of Indian Ocean thermocline water (14 x 10(6) cubic meters per second) into the South Atlantic Ocean. This circulation configuration, similar to that observed by earlier researchers, suggests that Indian-Atlantic thermocline exchange is a common occurrence. Such a warmwater link between the Atlantic and Indian oceans would strongly influence global climate patterns. The Indian Ocean water is warmer than the adjacent South Atlantic water and thus represents a heat input of 2.3 x 10(13) to 47 x 10(13) watts into the Atlantic. The large uncertainty arises from the unknown partition between two possible routes for the return flow from the Atlantic to the Indian Ocean: cooler South Atlantic thermocline water or much colder North Atlantic Deep Water. In either case, interocean mass and heat exchange of thermocline water at the Agulhas Retroflection is a distinct likelihood.

  20. 33 CFR 80.160 - Montauk Point, NY to Atlantic Beach, NY.

    Science.gov (United States)

    2010-07-01

    ... Light 322° true across the southwest tangent of the island on the north side of Jones Inlet to the... to Atlantic Beach, NY. (a) A line drawn from the Shinnecock Inlet East Breakwater Light to Shinnecock Inlet West Breakwater Light 1. (b) A line drawn from Moriches Inlet East Breakwater Light to...

  1. 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.

    Science.gov (United States)

    Larsen, A H; Sigurjónsson, J; Oien, N; Vikingsson, G; Palsbøll, P

    1996-11-22

    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 six microsatellite loci as well as the sequence of the first 288 nucleotides in the mitochondrial control region of 133 skin biopsies collected from humpback whales in the central North Atlantic (Iceland and Jan Mayen) and the northeastern North Atlantic (Bear Island and the northern coast of Norway). We detected no significant deviations from Hardy-Weinberg proportions nor any differences in genotype frequencies between localities at the nuclear loci. However, the mitochondrial analyses revealed two distinct matrilineal aggregations: the central and the northeastern North Atlantic. Our findings were not compatible with the idea of a separate eastern North Atlantic breeding ground unless one has been established recently. The proposed alternative hypothesis of a common North Atlantic panmictic population (wintering primarily in the West Indies) in which individual whales display maternally directed site-fidelity to specific feeding grounds was supported by re-sightings of two northeastern North Atlantic humpback whales in the West Indies.

  2. Mid-Atlantic Regional Wind Energy Institute

    Energy Technology Data Exchange (ETDEWEB)

    Courtney Lane

    2011-12-20

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

  3. 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...

  4. 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...

  5. 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.

  6. 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.

  7. 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...

  8. 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

    document late-Holocene climate variability in West Greenland as inferred from a marine sediment record from the outer Disko Bay. Organic-walled dinoflagellate cysts and other palynomorphs were used to reconstruct environmental changes in the area through the last c. 1500 years at 30–40 years resolution....... 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......Ribeiro, S., Moros, M., Ellegaard, M. & Kuijpers, A. 2012 (January): Climate variability in West Greenland during the past 1500 years: evidence from a high-resolution marine palynological record from Disko Bay. Boreas, Vol. 41, pp. 68–83. 10.1111/j.1502-3885.2011.00216.x. ISSN 0300-9483. Here we...

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

    CERN Document Server

    Dacie, Sally

    2015-01-01

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

  10. Identification of Atlantic Ocean Sea Surface Temperatures Drivers of French Streamflow

    Science.gov (United States)

    Aziz, O. A.; Tootle, G. A.; Anderson, S.

    2010-12-01

    The identification of Atlantic Ocean climatic drivers [e.g., Sea Surface Temperature (SST) variability] may be valuable in long lead-time forecasting of streamflow in France. Previous research efforts have identified the North Atlantic Oscillation (NAO) and the Atlantic Multidecadal Oscillation (AMO) as drivers of European hydrology. The current research applies, for the first time, the Singular Value Decomposition (SVD) statistical method to Atlantic Ocean SSTs and French streamflow to identify the primary Atlantic Ocean climatic driver of French streamflow. The use of Atlantic Ocean SSTs as a whole eliminates any biased that may be associated with using a predefined region of SSTs (e.g., AMO). Approximately 60 unimpaired streamflow stations with a period of record beginning around 1960 were evaluated and 25 were usable due to missing data. These data were obtained from the hydrology website of the Ministry of Ecology and Sustainable Development - Ministère de l’Ecologie et du Developpment Durable (http://www.hydro.eaufrance.fr). The Atlantic Ocean SST data cover the region spanning from 20° South to 60° North and 80° West to 2° West and were obtained from the National Climatic Data Center website (http://www.cdc.noaa.gov/cdc/data.noaa.erSST.html). AMO index values are available from the National Oceanic and Atmospheric Administration (NOAA) Climate Diagnostics Center (CDC) (http://www.cdc.noaa.gov/ClimateIndices/) and NAO index values were obtained from the National Center for Atmospheric Research (NCAR) website (http://www.cgd.ucar.edu/cas/jhurrell/indices.html). SVD has been used previously in similar studies, evaluating Pacific (should this be Pacific?), Atlantic, and global SSTs with various hydrologic responses including streamflow, precipitation, snowpack, and drought. Seasonal and yearly French streamflow are the hydrologic response while average Atlantic Ocean SSTs calculated for three different six month windows (January-June or JFMAMJ, April

  11. Call From China West

    Institute of Scientific and Technical Information of China (English)

    Yang Wei; Guo Jin

    2008-01-01

    @@ The 12th East-West China Cooperation and Investment and Trade Fair was held from April 5 to 8 at the International Conference and Exhibition Center in Qu-jiang,Xi'an.Shaanxi province,in the west of China.

  12. 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.)

  13. 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.)

  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. Blooming Seas West of Ireland

    Science.gov (United States)

    2007-01-01

    For several weeks in May and early June, daily satellite images of the North Atlantic Ocean west of Ireland have captured partial glimpses of luxuriant blooms of microscopic marine plants between patches of clouds. On June 4, 2007, the skies over the ocean cleared, displaying the sea's spring bloom in brilliant color. A bright blue bloom stretches north from the Mouth of the River Shannon and tapers off like a plume of blue smoke north of Clare Island. (In the large image, a second bloom is visible to the north, wrapping around County Donegal, on the island's northwestern tip.) The image was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite. Cold, nutrient-stocked water often wells up to the surface from the deeper ocean along coastal shelves and at the edges of ocean currents. When it does, it delivers a boost of nutrients that fuel large blooms of single-celled plants collectively known as phytoplankton. The plants are the foundation of the marine food web, and their proliferation in this area of the North Atlantic explains why the waters of western Ireland support myriad fisheries and populations of large mammals like seals, whales, and dolphins. Like plants on land, phytoplankton make their food through photosynthesis, harnessing sunlight for energy using chlorophyll and other light-capturing pigments. The pigments change the way light reflects off the surface water, appearing as colorful swirls of turquoise and green against the darker blue of the ocean. Though individually tiny, collectively these plants play a big role in Earth's carbon and climate cycles; worldwide, they remove about as much carbon dioxide from the atmosphere during photosynthesis as land plants do. Satellites are the only way to map the occurrence of phytoplankton blooms across the global oceans on a regular basis. That kind of information is important not only to scientists who model carbon and climate, but also to biologists and fisheries

  16. 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.

  17. JPRS Report, West Europe.

    Science.gov (United States)

    1988-07-12

    to lasting forms of energy, that a system to promote cleaner technologies, including pro- visions for recycling, be established together with an...Navas and Tania Juanes] [Text] Madrid—The North Atlantic Treaty Organization has sent the Spanish Government a letter in which it voices its

  18. Purge at West Valley

    Science.gov (United States)

    Mack, Warren

    1977-01-01

    Tells how the adviser of the student newspaper at West Valley College (Saratoga, California) was dismissed after the newspaper published stories based on investigations into alleged wrongdoings by administration members. (GW)

  19. 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...

  20. Dracaena in West Africa

    NARCIS (Netherlands)

    Bos, J.J.

    1984-01-01

    This taxonomic revision of the genus Dracaena L. (Liliaceae) in West Africa is another contribution towards a monograph on this group.Short general chapters contain historical, phytogeographical, morphological and phylogenetic observations. The taxonomic treatment contains a revised genus descriptio

  1. West Nile Virus

    Science.gov (United States)

    ... Respond to Pre-Award Requests Manage Your Award Negotiation & Initial Award After Award ... New Trial Launched in West Africa to Evaluate Three Vaccination Strategies , April 6, 2017 Monoclonal Antibody Cures Marburg Infection ...

  2. 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

  3. Eastern Culture Gone West

    Institute of Scientific and Technical Information of China (English)

    ZHANGHONG

    2005-01-01

    THE implication of one of British 19th century writer Rudyard Kipling's most famous quotations: “East is East,West is West and never the twain shall meet” is endorsed by contemporary scholar Dr Samuel Huntington in his work The Clash of Civilizations, in which he asserts that future wars will not be between individual states and political unions but between differing civilizations.

  4. Hydrography of the West Spitsbergen Current, Svalbard Branch: Autumn 2001

    Science.gov (United States)

    Cokelet, Edward D.; Tervalon, Nicole; Bellingham, James G.

    2008-01-01

    The Atlantic inflow is the primary source of water and heat to the Arctic Ocean. A large portion enters through Fram Strait where it splits into the Yermak and Svalbard Branches. In October to November 2001 the USCGC Healy occupied five oceanographic transects across the Svalbard Branch west and north of Spitsbergen. Temperature and salinity sections show the warm, salty Atlantic Water cooling and freshening as it flows along the continental slope for 553 km. The temperature in the upper 500 m of the water column decreased by 0.25°C/(100 km) implying a heat flux across the sea surface of up to 520 W/m2 if one assumes a nominal current of speed of 0.1 m/s. A temperature-salinity (T-S) analysis shows that the shape of the T-S curves can be explained in terms of the ratio of the atmospheric-to-ice-melt heat flux. The observations imply that ice melt accounts for progressively more surface cooling as the flow moves toward the Arctic Ocean. An autonomous underwater vehicle completed a vertical section in the region of maximum water mass gradient and revealed layer interleaving in fine detail. Data from this cruise extend a long time series of Atlantic layer source temperature beginning in 1910 (Saloranta and Haugan, 2001). The extended observations show that after the temperature of the Atlantic layer inflow reached a peak in 1992, it cooled to a minimum in 1998 and rose again through 2001.

  5. 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.

  6. Impact of the equatorial Atlantic on the El Nino Southern oscillation

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Hui; Keenlyside, Noel S.; Latif, Mojib [IFM-GEOMAR, Kiel (Germany)

    2012-05-15

    Observations indicate that the Atlantic zonal mode influences El Nino Southern oscillation (ENSO) in the Pacific, as already suggested in previous studies. Here we demonstrate for the first time using partial coupled experiments that the Atlantic zonal mode indeed influences ENSO. The partial coupling experiments are performed by forcing the coupled general circulation model (ECHAM5/MPI-OM) with observed sea surface temperature (SST) in the Tropical Atlantic, but with full air-sea coupling allowed in the Pacific and Indian Ocean. The ensemble mean of a five member simulation reproduces the observational results well. Analysis of observations, reanalysis, and coupled model simulations all indicate the following mechanism: SST anomalies associated with the Atlantic zonal mode affect the Walker Circulation, driving westward wind anomalies over the equatorial Pacific during boreal summer. The wind stress anomalies increase the east-west thermocline slope and enhance the SST gradient across the Pacific; the Bjerknes positive feedback acts to amplify these anomalies favouring the development of a La Nina-like anomalies. The same mechanisms act for the cold phase of Atlantic zonal mode, but with opposite sign. In contrast to previous studies, the model shows that the influence on ENSO exists before 1970. Furthermore, no significant influence of the Tropical Atlantic on the Indian Monsoon precipitation is found in observation or model. (orig.)

  7. 78 FR 64199 - Fisheries of the South Atlantic; South Atlantic Fishery Management Council; Public Meeting

    Science.gov (United States)

    2013-10-28

    .... SUMMARY: The South Atlantic Fishery Management Council's (Council) Scientific and Statistical Committee... Atlantic Fishery Management Council; Public Meeting AGENCY: National Marine Fisheries Service (NMFS...: (800) 445-8667 or (843) 308- 9330. Council address: South Atlantic Fishery Management Council,...

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

    Science.gov (United States)

    2011-09-16

    ... Species; Atlantic Shark Management Measures AGENCY: National Marine Fisheries Service (NMFS), National... Atlantic shark landings; request for comments. SUMMARY: This notice announces the National Marine Fisheries... Atlantic shark fisheries. NMFS published an Advanced Notice of Proposed Rulemaking (ANPR) on September...

  9. Extratropical North Atlantic SST influence on Sahel rainfall

    Science.gov (United States)

    Liu, Y.; Chiang, J. C.

    2013-12-01

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

  10. Atlantic Offshore Seabird Dataset Catalog

    Data.gov (United States)

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

  11. Atlantic Flyway Breeding Waterfowl Survey

    Data.gov (United States)

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

  12. Atlantic Flyway Sea Duck Survey

    Data.gov (United States)

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

  13. 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...

  14. 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...

  15. Contrasting patterns of α- and β-diversity in deep-sea bivalves of the eastern and western North Atlantic

    Science.gov (United States)

    Brault, Solange; Stuart, Carol T.; Wagstaff, Martine C.; McClain, Craig R.; Allen, John A.; Rex, Michael A.

    2013-08-01

    We analyzed patterns of α- and β-diversity in deep-sea bivalves collected by epibenthic sleds from the western North Atlantic south of New England, and from the eastern North Atlantic in the Rockall Trough, Porcupine Seabight and Porcupine Abyssal Plain. In the western North Atlantic, species diversity, measured as the normalized expected number of species, shows a unimodal bathymetric trend peaking at mid-bathyal depths. In the eastern North Atlantic, diversity increases monotonically with depth reaching a maximum at abyssal depths. We used Baselga's (2010) metrics to distinguish two separate components of β-diversity along depth gradients, species dissimilarity among sites due to spatial replacement (turnover) and species loss leading to nestedness. We also examined the rank order of nestedness with depth using Rodríguez-Gironés and Santamaría's (2006) BINMATNEST. The primary difference in β-diversity between west and east centers on the composition of abyssal communities. In the western North Atlantic, abyssal assemblages are nested subsets of bathyal assemblages. In the eastern North Atlantic, turnover dominates at all depths. These very fundamental differences in community structure between the basins may be attributable to differences in food supply, which is greater in the eastern North Atlantic region sampled. POC-flux to abyssal depths in the east may not reach levels low enough to depress species diversity as it does in the west. In the west, the abyssal fauna is largely an impoverished nested subset of the bathyal fauna that shows less endemism and may be maintained partly by source-sink dynamics.

  16. The North Atlantic Cold Bias

    Science.gov (United States)

    Greatbatch, Richard; Drews, Annika; Ding, Hui; Latif, Mojib; Park, Wonsun

    2016-04-01

    The North Atlantic cold bias, associated with a too zonal path of the North Atlantic Current and a missing "northwest corner", is a common problem in coupled climate and forecast models. The bias affects the North Atlantic and European climate mean state, variability and predictability. We investigate the use of a flow field correction to adjust the path of the North Atlantic Current as well as additional corrections to the surface heat and freshwater fluxes. Results using the Kiel Climate Model show that the flow field correction allows a northward flow into the northwest corner, largely eliminating the bias below the surface layer. A surface cold bias remains but can be eliminated by additionally correcting the surface freshwater flux, without adjusting the surface heat flux seen by the ocean model. A model version in which only the surface fluxes of heat and freshwater are corrected continues to exhibit the incorrect path of the North Atlantic Current and a strong subsurface bias. Removing the bias impacts the multi-decadal time scale variability in the model and leads to a better representation of the SST pattern associated with the Atlantic Multidecadal Variability than the uncorrected model.

  17. 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.

  18. Post-Glacial Development of Western North Atlantic - Labrador Sea Oceanographic Circulation

    DEFF Research Database (Denmark)

    Sheldon, Christina

    2015-01-01

    North Atlantic. A brief stratification event was recorded in Placentia Bay, likely tied to the drainage of glacial Lake Agassiz, after which the Labrador Current strengthened. The Labrador Current remained the major influence around Newfoundland and the western North Atlantic. During the late Holocene...... impact on the Greenland margins after the end of the last glacial period and through the Holocene, are examined based on analyses of sediment cores from the Uummannaq Trough, West Greenland. Marine sediment cores were taken from the Uummannaq Trough on the continental shelf of central West Greenland....... The core sites were chosen in an effort to track the retreat of the edge of the ice sheet after the Last Glacial Maximum. Similar to the other core sites, the cores were analysed using benthic foraminiferal assemblages in addition to bathymetry, quantitative x-ray diffraction analyses, and lithological...

  19. Convective lofting links Indian Ocean air pollution to paradoxical South Atlantic ozone maxima

    Science.gov (United States)

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

    2005-01-01

    We describe a broad resolution of the Atlantic Parado concerning the seasonal and geographic distribution, of tropical tropospheric ozone. We highlight periods of significant maximum tropospheric O3 for Jan.- April, 1999, exploiting satellite estimates and SHADOZ (Southern Hemisphere Additional Ozonesondes). Trajectory analyses connecting sondes and Total Tropospheric Ozone (TTO) maps suggest a complex influence from the Indian Ocean: beginning with mixed combustion sources, then low level transport, cumulonimbus venting, possible stratospheric input, and finally high-level transport to the west, with possible mixing over Africa. For the Jan.-March highest column-O3 periods in the Atlantic, distinct sounding peaks trace to specific NO sources, especially lightning, while in the same episodes, recurring every 20-50 days, more diffuse buildups of Indian-to-Atlantic pollution make important contributions.

  20. West Europe Report

    Science.gov (United States)

    2007-11-02

    Evils of Socialized Enterprises 84 ITALY Labor Outlines Platform for ENEL Contract Negotiations (Alessandra Urbano ; RASSEGNA SINDACALE, 8 Mar 85...Icelandic 3 May 85 p 36 [Article: ’"Nations of the North Atlantic Have Similar Interests in Fisheries, Marketing and Security Issues,’ says Geir...since they all have common interests in the area in fisheries protection, fisheries, marketing and, last but not least, security matters

  1. 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.

  2. Agulhas leakage into the Atlantic estimated with subsurface floats and surface drifters

    Science.gov (United States)

    Richardson, Philip L.

    2007-08-01

    Surface drifters and subsurface floats drifting at depths near 800 m were used to study the pathways of warm, salty Indian Ocean water leaking into the South Atlantic that is a component of the upper limb of the Atlantic meridional overturning circulation (MOC). Four drifters and 5 floats drifted from the Agulhas Current directly into the Benguela Current. Others looped for various amounts of time in Agulhas rings and cyclones, which translated westward into the Atlantic, contributing a large part of Indian Ocean leakage. Agulhas rings translated into the Benguela Current, where they slowly decayed. Some large, blob-like Agulhas rings with irregular shapes were found in the southeastern Cape Basin. Drifter trajectories suggest these rings become more circular with time, eventually evolving into the circular rings observed west of the Walvis Ridge. Agulhas cyclones, which form on the north side of the Agulhas Current south of Africa, translated southwestward (to 6°E) and contributed water to the southern Cape Basin. A new discovery is a westward extension from the mean Agulhas retroflection measured by westward drifting floats near 41°S out to at least 5°W, with some floats as far west as 25°W. The Agulhas extension appears to split the South Atlantic Current (SAC) into two branches and to transport Agulhas water westward, where it is mixed and blended with eastward-flowing water from the western Atlantic. The blended mixture flows northeastward in the northern branch of the SAC and into the Benguela Current. Agulhas leakage transport was estimated from drifters and floats to be at least 15 Sv in the upper 1000 m, which is equivalent to the transport of the upper layer MOC. It is suggested that the major component of the upper layer overturning circulation in the Atlantic is Agulhas leakage in the form of Agulhas rings.

  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 Atlantic Multi-Decadal Oscillation Impact on Regional Climate

    Science.gov (United States)

    Werner, Rolf; Valev, Dimitar; Atanassov, Atanas; Danov, Dimitar; Guineva, Veneta; Kirillov, Andrey S.

    2016-07-01

    The Atlantic multi-decadal oscillation (AMO) shows a period of about 60-70 years. Over the time span from 1860 up to 2014 the AMO has had a strong climate impact on the Northern Hemisphere. The AMO is considered to be related to the Atlantic overturning circulation, but the origin of the oscillation is not fully understood up till now. To study the AMO impact on climate, the Hadcrut4, Crut4 and HadSST3 temperature data sets have been employed in the current study. The influence of the AMO on the zonal and meridional temperature distribution has been investigated in detail. The strongest zonal AMO impact was obtained in the Arctic region. The results indicated that the AMO influence on temperature at Southern latitudes was opposite in phase compared to the temperature influence in the Northern Hemisphere, in agreement with the well known heat transfer phenomenon from South to North Atlantic. In the Northern Hemisphere the strongest AMO temperature impact was found over the Atlantic and America. In the West from American continent, over the Pacific, the AMO impact was the lowest obtained over the whole Northern Hemisphere. The Rocky Mountains and Sierra Madre, connected with it southwards, built up an atmospheric circulation barrier preventing a strong propagation of the AMO temperature signal westerly. The amplitude of the AMO index itself was greater during summer-fall. However stronger AMO influence on the Northern Hemisphere temperatures was found during the fall-winter season, when the differences between the Northern Hemisphere temperatures and the temperatures in the tropics were the greatest.

  5. 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,...

  6. West Virginia Community Colleges.

    Science.gov (United States)

    Miller, Eldon L.; Dziagwa, Constance E.

    1997-01-01

    Discusses efforts over the past 25 years to formalize the role of West Virginia's community colleges in the context of the state's rural character and low college graduation rates. Describes a reorganization following a 1987 study by the Carnegie Foundation and state legislation designed to fine tune the colleges' mission. (10 citations) (AJL)

  7. 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...

  8. 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).

  9. Invigorating West China

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The once-poor west China is growing at a faster rate than the east. The trend is set to continue over the next few years. This is good news for China as the country gears up to shrink the economic divide between eastern and western regions.

  10. Atlantic NAD 83 OCS Planning Areas

    Data.gov (United States)

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

  11. 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...

  12. FAQ: General Questions about West Nile Virus

    Science.gov (United States)

    ... Public Service Videos General Questions About West Nile Virus Recommend on Facebook Tweet Share Compartir On this ... West Nile virus cases? What is West Nile virus? West Nile virus is an arthropod-borne virus ( ...

  13. 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

  14. Atlantic CFC data in CARINA

    Directory of Open Access Journals (Sweden)

    R. Steinfeldt

    2010-01-01

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

  15. Physical and remineralization processes govern the cobalt distribution in the deep western Atlantic ocean

    Directory of Open Access Journals (Sweden)

    G. Dulaquais

    2013-10-01

    Full Text Available The distributions of the bio-essential trace element dissolved Co (DCo and the apparent particulate Co (PCo are presented along the GEOTRACES-A02 deep section from 64° N to 50° S in the West Atlantic Ocean. PCo was determined as the difference between total cobalt (TCo, unfiltered samples and DCo. DCo concentrations ranged from 14.7 pM to 94.3 pM, and PCo concentrations from undetectable values to 18.8 pM. The lowest DCo concentrations were observed in the subtropical domains, and the highest in the low-oxygenated Atlantic Central Waters (ACW that appeared to be the major reservoir of DCo in the West Atlantic. In the Antarctic Bottom Waters, the enrichment in DCo with ageing of the water-mass can be related to suspension and redissolution of bottom sediments a well as diffusion of DCo from abyssal sediments. Mixing and dilution of deep water-masses, rather than scavenging of DCo onto settling particles, generated the meridional decrease of DCo along the southward large-scale circulation in the deep West Atlantic. Furthermore the apparent scavenged profile of DCo observed in the deep waters likely resulted from the persistence of relatively high concentrations in intermediate waters and low DCo concentrations in underlaying bottom waters. We suggested that the 2010 Icelandic volcanic eruption can be a source of DCo that could have been transported in the core of the North-East Atlantic Deep Waters. At intermediate depths, the high concentrations of DCo recorded in the ACW linearly correlated with the apparent utilization of oxygen (AOU, indicating that remineralization of DCo can be significant (representing up to 29% of the DCo present. Furthermore the preferential remineralization of phosphate (P compared to Co in these low-oxygenated waters suggested a decoupling between the deep cycles of P and Co. The vertical diffusion of DCo from the ACW appeared to be a significant source of DCo into the surface waters of the equatorial domain

  16. West Candor Chasma

    Science.gov (United States)

    1996-01-01

    During its examination of Mars, the Viking 1 spacecraft returned images of Valles Marineris, a huge canyon system 5,000 km long, up to 240 km wide, and 6.5 km deep, whose connected chasma or valleys may have formed from a combination of erosional collapse and structural activity. The view shows west Candor Chasma, one of the connected valleys of Valles Marineris; north toward top of frame. The image is a composite of Viking high-resolution (about 80 m/pixel or picture element) images in black and white and low resolution (about 250 m/pixel) images in color. The Viking 1 craft landed on Mars in July of 1976. West Candor Chasma occupies the westernmost part of the large west-northwest-trending trough of Candor Chasma. This section is about 150 km wide. West Candor Chasma is bordered on the north and south by straight-walled cliffs, most likely faults, and on its west by two segments of north-northeast-trending cliffs. The north wall is dissected by landslide scars forming reentrants filled with landslide debris. The south wall shows spur-and-gully morphology and smooth sections. The high-standing central mesa, informally dubbed Red Mesa has several curvilinear reentrants carved into the caprock, whose anomalously colored layers were interpreted to be caused by young hydrothermal alteration products (Geissler et al., 1993, Icarus, v. 106, p. 380-391). Light-colored lobes flow away from the top of the interior stack and then flow around and embay the same layered stack from which they originated. One of these apparent flow features is composed of at least two or perhaps even three huge, superposed, vaguely layered, very rugged, light-colored lobes as much as 100 km long, 20 km wide, and over 2 km thick. The layered deposits below the caprock also merge with a chaotic material that has local lobate fronts and overlaps landslide deposits. Hummocky material, similar in hue to wall rock, fills the southwestern-most region of west Candor Chasma and is perhaps as much as 3

  17. JPRS Report, West Europe.

    Science.gov (United States)

    2007-11-02

    was no tabula rasa politically. He had worked with EEC Commissioners Sicco Mansholt and Henri Simonet, had represented the Young Socialists in the...OF GERMANY Civil-Military Facilitator Role Proposed for Territorial Army (Hans-Lothar Stegmann; TRUPPENPRAXIS, Mar 87) 80 FRANCE GIAT Problems...supportable. The attitude that Mikhail Gorbachev represents the same type of evil helps them to formulate a specific West German role in the Western world

  18. West Europe Report

    Science.gov (United States)

    1987-02-26

    WEST EUROPE REPORT CONTENTS POLITICAL EUROPEAN AFFAIRS Tindemans on Problems of Belgian EC Presidency ( Leo Tindemans Interview; LA LIBRE BELGIQUE...Interview with Minister of Foreign Relations Leo Tindemans; date and place not given] [Text] [Question] The implementation of the "Single Act," reform of...Izeboud was reelected in the party executive of 55 members, as were former members of the chamber Ina Brouwer , Marius Ernsting and Evelien Eshuis

  19. Distribution and drift of Atlantic cod ( Gadus morhua ) eggs and larvae in Greenland offshore waters

    DEFF Research Database (Denmark)

    Wieland, Kai; Hovgård, Holger

    2002-01-01

    Catches of Atlantic cod (Gadus morhua) eggs and larvae from 45 national and international ichthyoplankton surveys conducted in Greenland offshore waters during the period 1950 to 1984 have been compiled and re-analysed. Southeast and Southwest Greenland were identified as im- portant spawning areas...... from which eggs and early larvae drift towards the southern Davis Strait. Only a part of the larval population remained in the vicinity of favourable settling areas off West Greenland while a considerable part was obviously transported westward across the Davis Strait and thus did not contribute...... to the recruitment of the West Greenland cod stock. It is also shown that cod eggs and larvae occasionally drift from Southwest Iceland across the Denmark Strait to the East Greenland shelf from where a subsequent transport and immigration of juveniles to West Greenland waters can occur. Larval transport across...

  20. Drought in West Africa

    Science.gov (United States)

    2007-01-01

    Drought settled over West Africa's Ivory Coast region when wet season rains came late in 2007. Instead of beginning in February, the rainy season didn't start until March, and steady rains didn't start until late March, said the Famine Early Warning System Network. Though the rain had started to alleviate the drought, vegetation was still depressed in parts of Cote d'Ivoire (Ivory Coast) between March 22 and April 6, 2007, when the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite captured the data used to make this image. The image shows current vegetation conditions compared to average conditions recorded since 2000. Areas where plants are growing more slowly or more sparsely than average are brown, while areas where vegetation is denser than average are green. The brown tint that dominates the image indicates that plants through most of the country are more sparse than normal. Among the crops affected by the lack of rain was West Africa's cocoa crop. About 70 percent of the world's cocoa comes from West Africa, and Cote d'Ivoire is a top grower, said Reuters. Cocoa prices climbed as the crop fell short. Farmers called the drought the worst in living memory, Reuters said. The delay in rainfall also led to water shortages in parts of Cote d'Ivoire, according to the United Nations Office for the Coordination of Humanitarian Affairs.

  1. West and Central Africa.

    Science.gov (United States)

    Lydie, N; Robinson, N J

    1998-01-01

    This article reviews scientific and other literature during the 1990s that links migration and mobility with the spread of sexually transmitted diseases (STDs), including HIV/AIDS. The focus is on key population groups linked to the spread of HIV and STDs in West and Central Africa: migrant laborers, truck drivers, itinerant traders, commercial sex workers (CSWs), and refugees. Countries with high emigration and immigration tend to have high levels of HIV infection, with the exception of Senegal. The main destination of immigrants are Senegal, Nigeria, and Cote d'Ivoire in West Africa and Cameroon, Congo, Gabon, and Congo in Central Africa. The risk of infection and the spread of HIV is variable among migrants. There is little in the literature that substantiates hypotheses about the strong association between migration and HIV-positive status. Information is needed on the duration, frequency of return visits, living conditions, sexual activities with multiple partners, and information before departure, along the routes, at final destination, and at the time of returns. Action-based research in five West African countries (Burkina Faso, Cote d'Ivoire, Mali, Niger, and Senegal) should produce results in late 1998. Comparable studies in Central Africa are unknown. Regional studies should be complemented by local studies. Prevention would benefit from studies on the relative size of these five population groups by geographic location.

  2. Distribution patterns in Atlantic hydroids

    NARCIS (Netherlands)

    Medel, M.D.; López-González, P.J.

    1998-01-01

    The present study is a first attempt to comparing the hydroid faunas of the various Zoogeographie areas of the Atlantic Ocean. We restricted ourselves to species of the orders Antho- and Leptomedusae, of which 1050 species were taken into account. The classification of zoogeographic areas used follo

  3. Witches in the Atlantic World.

    Science.gov (United States)

    Breslaw, Elaine

    2003-01-01

    Presents a lesson plan that focuses on witchcraft in the Atlantic world. Describes each of the four sections of the lesson that encompasses learning about terms and religious views on witchcraft to the history of witchcraft in New England, in the United States, and the Salem (Massachusetts) witchcraft trials. (CMK)

  4. Marine biodiversity in the Atlantic and Pacific coasts of South America: knowledge and gaps.

    Directory of Open Access Journals (Sweden)

    Patricia Miloslavich

    Full Text Available The marine areas of South America (SA include almost 30,000 km of coastline and encompass three different oceanic domains--the Caribbean, the Pacific, and the Atlantic--ranging in latitude from 12∘N to 55∘S. The 10 countries that border these coasts have different research capabilities and taxonomic traditions that affect taxonomic knowledge. This paper analyzes the status of knowledge of marine biodiversity in five subregions along the Atlantic and Pacific coasts of South America (SA: the Tropical East Pacific, the Humboldt Current,the Patagonian Shelf, the Brazilian Shelves, and the Tropical West Atlantic, and it provides a review of ecosystem threats and regional marine conservation strategies. South American marine biodiversity is least well known in the tropical subregions (with the exception of Costa Rica and Panama. Differences in total biodiversity were observed between the Atlantic and Pacific oceans at the same latitude. In the north of the continent, the Tropical East Pacific is richer in species than the Tropical West Atlantic, however, when standardized by coastal length, there is very little difference among them. In the south, the Humboldt Current system is much richer than the Patagonian Shelf. An analysis of endemism shows that 75% of the species are reported within only one of the SA regions, while about 22% of the species of SA are not reported elsewhere in the world. National and regional initiatives focusing on new exploration, especially to unknown areas and ecosystems, as well as collaboration among countries are fundamental to achieving the goal of completing inventories of species diversity and distribution.These inventories will allow accurate interpretation of the biogeography of its two oceanic coasts and latitudinal trends,and will also provide relevant information for science based policies.

  5. The climate influence on the mid-depth Northeast Atlantic gyres viewed by cold-water corals

    Science.gov (United States)

    Montero-Serrano, Jean-Carlos; Frank, Norbert; Colin, Christophe; Wienberg, Claudia; Eisele, Markus

    2011-10-01

    The neodymium (Nd) isotopic composition (expressed in epsilon units, $\\varepsilon$Nd) of reef framework-forming cold-water corals provides unique measures of water mass provenance and mixing within the Northeast Atlantic today and in the past. A reconstruction of near thermocline water $\\varepsilon$Nd from cold-water corals of the Gulf of Cádiz and Porcupine Seabight spanning over the past 300,000 years, now revealed that climate cooling during Marine Isotope Stages (MIS) 7.2 and MIS 8/9 led to a retraction of the mid-depth Subpolar Gyre (mSPG) to the west. Conversely, Northern Hemisphere warming and increasing fresh water fluxes to the northwest (Labrador Sea) favor a stronger eastward extension of the mSPG blocking the northward flow of temperate Atlantic water as observed during the early MIS 1 and the early stage MIS 5.5. These changes are likely the result of large-scale south-north displacement of the westerlies similar to present-day observations that the North Atlantic Oscillation (NAO) is linked with mid-depth ocean circulation. Based on these observations, we hypothesize that further climate warming will also strengthen the mSPG leading to a salt and temperature decrease in the Northeast Atlantic whereas salinity and temperature will increase in the temperate Atlantic. However, the amplitude of such changes on North Atlantic overturning remains to be tested.

  6. JPRS Report, West Europe

    Science.gov (United States)

    2007-11-02

    in French 24 Jun 87 p 2 [Article by Ch. B.] [Text] A crisis? In the PSC? You’re dreaming . Or else you are seeking to destroy stability in the...partners. The ups and downs of recent weeks have done him harm, and it said that he dreams of distancing himself somewhat. If only Willy De Clercq were...a lucid and objective account of his subject matter. It is still quite common for more or less well-informed West Europeans to use the term

  7. Array Analysis of North Atlantic Microseisms

    Science.gov (United States)

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

    2016-04-01

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

  8. Long distance dispersal and connectivity in amphi-Atlantic corals at regional and basin scales.

    Directory of Open Access Journals (Sweden)

    Flavia L D Nunes

    Full Text Available Among Atlantic scleractinian corals, species diversity is highest in the Caribbean, but low diversity and high endemism are observed in various peripheral populations in central and eastern Atlantic islands and along the coasts of Brazil and West Africa. The degree of connectivity between these distantly separated populations is of interest because it provides insight into processes at both evolutionary and ecological time scales, such as speciation, recruitment dynamics and the persistence of coral populations. To assess connectivity in broadly distributed coral species of the Atlantic, DNA sequence data from two nuclear markers were obtained for six coral species spanning their distributional ranges. At basin-wide scales, significant differentiation was generally observed among populations in the Caribbean, Brazil and West Africa. Concordance of patterns in connectivity among co-distributed taxa indicates that extrinsic barriers, such as the Amazon freshwater plume or long stretches of open ocean, restrict dispersal of coral larvae from region to region. Within regions, dispersal ability appears to be influenced by aspects of reproduction and life history. Two broadcasting species, Siderastrea siderea and Montastraea cavernosa, were able to maintain gene flow among populations separated by as much as 1,200 km along the coast of Brazil. In contrast, brooding species, such as Favia gravida and Siderastrea radians, had more restricted gene flow along the Brazilian coast.

  9. Population structure of Squatina guggenheim (Squatiniformes, Squatinidae) from the south-western Atlantic Ocean.

    Science.gov (United States)

    Garcia, G; Pereyra, S; Gutierrez, V; Oviedo, S; Miller, P; Domingo, A

    2015-01-01

    Population genetic analyses based on both mitochondrial cytochrome b and the internal transcribed spacer 2 of recombinant (r)DNA genes were implemented to examine hypotheses of population differentiation in the angular angel shark Squatina guggenheim, one of the four most-widespread endemic species inhabiting coastal ecosystems in the south-western Atlantic Ocean. A total of 82 individuals of S. guggenheim from 10 sampling sites throughout the Río de la Plata mouth, its maritime front, the outer shelf at the subtropical confluence and the coastal areas of the south-west Atlantic Ocean, were included. The analysis of molecular variance (AMOVA) based on the second internal transcribed spacer (its-2) region supports that the samples from the outer shelf represent an isolated group from other sites. Historical gene flow in a coalescent-based approach revealed significant immigration and emigration asymmetry between sampling sites. Based on the low level of genetic diversity, the existence of a long-term population decline or a past recent population expansion following a population bottleneck could be proposed in S. guggenheim. This demographic differentiation suggests a degree of vulnerability to overexploitation in this endemic and endangered south-west Atlantic Ocean shark, given its longevity and low reproductive potential.

  10. African Easterly Waves and Cyclonic Activity over the Eastern Atlantic: Composite and Case Studies

    Directory of Open Access Journals (Sweden)

    Moctar Camara

    2011-01-01

    Full Text Available This study aims to understand the main differences over the African continent and the Eastern Atlantic Ocean between African Easterly Waves (AEWs associated with Atlantic cyclones (developing AEWs and non-developing AEWs. A statistical study showed that most of the named cyclones generated near the West African coast have a long lifecycle and all are associated with intense AEWs. Using NCEP/NCAR reanalyses, a composite study of the characteristics of developing AEWs is carried out and compared to those of non-developing AEWs. Developing AEWs exhibit the greatest baroclinic and barotropic conversions which are known to be the main processes involved in AEWs growth suggesting that these AEWs are stronger than the non-developing ones. Moreover, the developing AEWs are characterized by the existence of a relatively more unstable environment over West Africa and the Atlantic Ocean. A case study using rawinsonde data showed that the developing AEW is associated with dynamic and thermodynamic conditions conducive for deep convection and subsequent cyclogenesis compared to the non-developing AEW case.

  11. 78 FR 48653 - Fisheries of the South Atlantic; South Atlantic Fishery Management Council; Public Meeting

    Science.gov (United States)

    2013-08-09

    ... Fishery Management Council (SAFMC) Scientific and Statistical Committee (SSC). SUMMARY: The SAFMC will... Atlantic Fishery Management Council; Public Meeting AGENCY: National Marine Fisheries Service (NMFS...: South Atlantic Fishery Management Council, 4055 Faber Place Drive, Suite 201, N. Charleston, SC...

  12. The Biological Standard of Living in Early Nineteenth-century West Africa: New Anthropometric Evidence for Northern Ghana and Burkina Faso

    NARCIS (Netherlands)

    Austin, G.; Baten, J.; van Leeuwen, B.

    2011-01-01

    West Africans are on average shorter than Europeans today. Whether this was already the case at the end of the Atlantic slave trade is an important question for the history of nutrition and physical welfare. We present the first study of changing heights for people born mostly in what are now northe

  13. What role does crustal heterogeneity play on continental break-up; the interplay of a foldbelt, rift system and ocean basin in the South Atlantic

    Science.gov (United States)

    Paton, Douglas; Mortimer, Estelle; Hodgson, Neil

    2015-04-01

    Although extensively studied, two key questions remain unanswered regarding the evolution of the southern South Atlantic. Firstly, where is the Cape Foldbelt (CFB) in offshore South Africa? The CFB is part of the broader Gonwanian Orogeny that prior to South Atlantic rifting continued into the Ventana Foldbelt of Argentina but to date its location in the offshore part of South Africa remains enigmatic. Secondly, the conjugate rift basin to South Africa is the Colorado Basin in Argentina but why does it trend east-west despite its perpendicular orientation to the Atlantic spreading ridge? Current plate models and structural understands cannot explain these fundamental questions. We use newly acquired deep reflection seismic data in the Orange Basin, South Africa, to develop a new structural model for the southern South Atlantic. We characterise the geometry of the Cape Foldbelt onshore and for the first time correlate it into the offshore. We show that it has a north-south trend immediately to the north of the Cape Peninsula but then has a syntaxis (Garies syntaxis) that results in a change to an east-west orientation. This forms the missing jigsaw piece of the Atlantic reconstruction as this is directly beside the restored Colorado Basin. When considered within the pre-break up structural configuration our observations imply that prior to the main phase of Atlantic rifting in the Mezosoic there was significant variation in crustal geometry incorporating the Orange Basin of South Africa, the Colorado Basin and the Gariep Belt of Namibia. These faults were active during Gondwana rifting, but the Colorado rift failed resulting in the present day location of the South Atlantic. Not only do our results improve our understanding of the evolution of the South Atlantic ocean, they highlight the importance of differentiating between early rift evolution and strain localisation during the subsequent rift phase prior to seafloor spreading.

  14. 78 FR 59916 - Fisheries of the South Atlantic; South Atlantic Fishery Management Council; Public Meeting

    Science.gov (United States)

    2013-09-30

    .... SUMMARY: The South Atlantic Fishery Management Council (SAFMC) will hold a meeting of its Scientific and... Atlantic Fishery Management Council; Public Meeting AGENCY: National Marine Fisheries Service (NMFS...; fax: (843) 744- 4472. Council address: South Atlantic Fishery Management Council, 4055 Faber...

  15. 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...

  16. 76 FR 67121 - Atlantic Highly Migratory Species; 2012 Atlantic Shark Commercial Fishing Season

    Science.gov (United States)

    2011-10-31

    ... Species; 2012 Atlantic Shark Commercial Fishing Season AGENCY: National Marine Fisheries Service (NMFS... season for the Atlantic commercial shark fisheries. Quotas would be adjusted based on any over- and/or underharvests experienced during the 2010 and 2011 Atlantic commercial shark fishing seasons. In addition,...

  17. 77 FR 61562 - Atlantic Highly Migratory Species; 2013 Atlantic Shark Commercial Fishing Season

    Science.gov (United States)

    2012-10-10

    ... Species; 2013 Atlantic Shark Commercial Fishing Season AGENCY: National Marine Fisheries Service (NMFS... season for the Atlantic commercial shark fisheries. Quotas would be adjusted as allowable based on any over- and/or underharvests experienced during the 2011 and 2012 Atlantic commercial shark...

  18. 77 FR 3393 - Atlantic Highly Migratory Species; 2012 Atlantic Shark Commercial Fishing Season

    Science.gov (United States)

    2012-01-24

    ...; 2012 Atlantic Shark Commercial Fishing Season AGENCY: National Marine Fisheries Service (NMFS... season for the Atlantic commercial shark fisheries. Quotas were adjusted based on over- and/or underharvests experienced during the 2010 and 2011 Atlantic commercial shark fishing seasons. In addition,...

  19. Carbon Cycling in the Arctic Archipelago: The Export of Pacific Carbon to the North Atlantic

    Science.gov (United States)

    Shadwick, E. H.; Papakyriakou, T.; Prowe, A. E. F.; Leong, D.; Moore, S.; Thomas, H.

    2009-04-01

    The Arctic Ocean is expected to be disproportionately sensitive to climatic changes, and thought to be an area where such changes might be detected. The Arctic hydrological cycle is influenced by: runoff and precipitation, sea ice formation/melting, and the inflow of saline waters from Bering and Fram Straits and the Barents Sea Shelf. Pacific water is recognizable as low salinity water, with high concentrations of dissolved inorganic carbon (DIC), flowing from the Arctic Ocean to the North Atlantic via the Canadian Arctic Archipelago. We present DIC data from an east-west section through the Archipelago, as part of the Canadian International Polar Year initiatives. The fractions of Pacific and Arctic Ocean waters leaving the Archipelago and entering Baffin Bay, and subsequently the North Atlantic, are computed. The eastward transport of carbon from the Pacific, via the Arctic, to the North Atlantic is estimated. Altered mixing ratios of Pacific and freshwater in the Arctic Ocean have been recorded in recent decades. Any climatically driven alterations in the composition of waters leaving the Arctic Archipelago may have implications for anthropogenic CO2 uptake, and hence ocean acidification, in the subpolar and temperate North Atlantic.

  20. Emerging impact of Greenland meltwater on deepwater formation in the North Atlantic Ocean

    Science.gov (United States)

    Böning, Claus W.; Behrens, Erik; Biastoch, Arne; Getzlaff, Klaus; Bamber, Jonathan L.

    2016-07-01

    The Greenland ice sheet has experienced increasing mass loss since the 1990s. The enhanced freshwater flux due to both surface melt and outlet glacier discharge is assuming an increasingly important role in the changing freshwater budget of the subarctic Atlantic. The sustained and increasing freshwater fluxes from Greenland to the surface ocean could lead to a suppression of deep winter convection in the Labrador Sea, with potential ramifications for the strength of the Atlantic meridional overturning circulation. Here we assess the impact of the increases in the freshwater fluxes, reconstructed with full spatial resolution, using a global ocean circulation model with a grid spacing fine enough to capture the small-scale, eddying transport processes in the subpolar North Atlantic. Our simulations suggest that the invasion of meltwater from the West Greenland shelf has initiated a gradual freshening trend at the surface of the Labrador Sea. Although the freshening is still smaller than the variability associated with the episodic `great salinity anomalies', the accumulation of meltwater may become large enough to progressively dampen the deep winter convection in the coming years. We conclude that the freshwater anomaly has not yet had a significant impact on the Atlantic meridional overturning circulation.

  1. Carbon cycling in the Arctic Archipelago: the export of Pacific carbon to the North Atlantic

    Directory of Open Access Journals (Sweden)

    E. H. Shadwick

    2009-01-01

    Full Text Available The Arctic Ocean is expected to be disproportionately sensitive to climatic changes, and is thought to be an area where such changes might be detected. The Arctic hydrological cycle is influenced by: runoff and precipitation, sea ice formation/melting, and the inflow of saline waters from Bering and Fram Straits and the Barents Sea Shelf. Pacific water is recognizable as intermediate salinity water, with high concentrations of dissolved inorganic carbon (DIC, flowing from the Arctic Ocean to the North Atlantic via the Canadian Arctic Archipelago. We present DIC data from an east-west section through the Archipelago, as part of the Canadian International Polar Year initiatives. The fractions of Pacific and Arctic Ocean waters leaving the Archipelago and entering Baffin Bay, and subsequently the North Atlantic, are computed. The eastward transport of carbon from the Pacific, via the Arctic, to the North Atlantic is estimated.

    Altered mixing ratios of Pacific and freshwater in the Arctic Ocean have been recorded in recent decades. Any climatically driven alterations in the composition of waters leaving the Arctic Archipelago may have implications for anthropogenic CO2 uptake, and hence ocean acidification, in the subpolar and temperate North Atlantic.

  2. Coherent changes of the circulation in the deep North Atlantic from moored transport arrays

    CERN Document Server

    Frajka-Williams, E; Koelling, J; Send, U

    2016-01-01

    In situ boundary arrays have been installed in the North Atlantic to measure the large-scale ocean circulation. Here, we use measurements at the western edge of the North Atlantic at $16^\\circ$N and $26^\\circ$N to investigate low-frequency variations in deep densities and their associated influence on ocean transports. At both latitudes, deep waters (below 1100 dbar) at the western boundary are becoming fresher and less dense. The associated change in geopotential thickness is about $0.15$ $\\mbox{m}^2\\mbox{s}^{-2}$ between 2004-2009 and 2010-2014, with the shift occurring between 2009-2010 and earlier at $26^\\circ$N than $16^\\circ$N. Without a similar density change on the east of the Atlantic, a mid-depth reduction in water density at the west drives an increase in the shear between the upper and lower layers of North Atlantic Deep Water of about 2.6 Sv at $26^\\circ$N and 3.9 Sv at $16^\\circ$N. While these transport anomalies result in an intensifying tendency in the meridional overturning circulation (MOC) ...

  3. 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.

  4. Ice stream retreat following the LGM and onset of the west Greenland current in Uummannaq Trough, west Greenland

    Science.gov (United States)

    Sheldon, Christina; Jennings, Anne; Andrews, John T.; Ó Cofaigh, Colm; Hogan, Kelly; Dowdeswell, Julian A.; Seidenkrantz, Marit-Solveig

    2016-09-01

    The deglacial history and oceanography of Uummannaq Trough, central West Greenland continental shelf, was investigated using foraminiferal, sedimentological, and bathymetric records together with a radiocarbon chronology, providing a timeline for the retreat of glacial ice after the Last Glacial Maximum (LGM). To map ice stream retreat, data were collected from cores from the outer (JR175-VC45 and JR175-VC43) and inner (JR175-VC42) Uummannaq Trough. A large ice stream, fed by confluent glaciers draining the interior of the Greenland Ice Sheet, extended across the outer shelf during the LGM and was in retreat by 15.0 cal kyr BP. Foraminiferal data indicate that the 'warm' West Greenland Current (WGC) was established prior to 14.0 cal kyr BP, which is the hitherto earliest record of Atlantic Water found on the West Greenland shelf. For each of the cores, foraminifera indicate that ice sheet retreat was followed quickly by incursion of the WGC, suggesting that the warm water may have enhanced ice retreat. Prior to the Younger Dryas cold event, the radiocarbon chronology indicates that the ice sheet retreated to the mid-shelf, where it subsequently stabilised and formed a large grounding-zone wedge (GZW). After the Younger Dryas, around 11.5 cal kyr BP, the ice retreated rapidly from the GZW and into the fjords.

  5. On the relationship between east equatorial Atlantic SST and ISM through Eurasian wave

    Science.gov (United States)

    Yadav, Ramesh Kumar

    2017-01-01

    The dominant mode of July-August (JA) seasonal variability of Indian summer monsoon rainfall (ISMR) are obtained by performing empirical orthogonal function (EOF) analysis. The first dominant mode of ISMR and its relationships with the sea surface temperature (SST), pressure level wind and geopotential height (GPH) fields are examined using gridded datasets for the period 1979-2014. The principal component of the first leading mode (PC1) obtained in the EOF analysis of JA rainfall over Indian landmass is highly correlated with north-west and central India rainfall, and anti-correlated with east-equatorial Atlantic SST (EEASST). The positive EEASST anomaly intensifies the inter-tropical convergence zone over Atlantic and west equatorial Africa which generates stationary wave meridionally, as meridional transfer of energy is strong, as the influence of background jet-streams are minimal over North Africa and Europe. The anomalous positive and negative GPH are generated over sub-tropics and extra-tropics, respectively, due to the stationary wave. This increases the climatological background steep pressure gradient between sub-tropics and extra-tropics consisting of anomalous negative GPH field over north-west (NW) Europe and vice versa for negative EEASST anomaly. The anomalous positive GPH over NW Europe acts as center of action for the propagation of a Rossby wave train to NW India via Europe consisting of anomalous high over NW of India. This intensifies the Tibetan High westward which reinforces the outbreak of monsoon activities over central and NW India.

  6. On the relationship between east equatorial Atlantic SST and ISM through Eurasian wave

    Science.gov (United States)

    Yadav, Ramesh Kumar

    2016-03-01

    The dominant mode of July-August (JA) seasonal variability of Indian summer monsoon rainfall (ISMR) are obtained by performing empirical orthogonal function (EOF) analysis. The first dominant mode of ISMR and its relationships with the sea surface temperature (SST), pressure level wind and geopotential height (GPH) fields are examined using gridded datasets for the period 1979-2014. The principal component of the first leading mode (PC1) obtained in the EOF analysis of JA rainfall over Indian landmass is highly correlated with north-west and central India rainfall, and anti-correlated with east-equatorial Atlantic SST (EEASST). The positive EEASST anomaly intensifies the inter-tropical convergence zone over Atlantic and west equatorial Africa which generates stationary wave meridionally, as meridional transfer of energy is strong, as the influence of background jet-streams are minimal over North Africa and Europe. The anomalous positive and negative GPH are generated over sub-tropics and extra-tropics, respectively, due to the stationary wave. This increases the climatological background steep pressure gradient between sub-tropics and extra-tropics consisting of anomalous negative GPH field over north-west (NW) Europe and vice versa for negative EEASST anomaly. The anomalous positive GPH over NW Europe acts as center of action for the propagation of a Rossby wave train to NW India via Europe consisting of anomalous high over NW of India. This intensifies the Tibetan High westward which reinforces the outbreak of monsoon activities over central and NW India.

  7. FAQ: West Nile Virus and Dead Birds

    Science.gov (United States)

    ... Education Public Service Videos West Nile Virus & Dead Birds Recommend on Facebook Tweet Share Compartir On This ... dead bird sightings to local authorities. How do birds get infected with West Nile virus? West Nile ...

  8. Argo floats revealing bimodality of large-scale mid-depth circulation in the North Atlantic

    Institute of Scientific and Technical Information of China (English)

    CHU Peter C; IVANOV Leonid M; MELNICHENKO Oleg V; LI Rongfeng

    2008-01-01

    Analysis of Argo float trajectories at 1000 m and temperature at 950 m in the North Atlantic between November 2003 and January 2005 demonstrates the existence of two different circulation modes with fast transition between them. Each mode has a pair of cy-clonic - anticyclonic gyres. The difference is the location of the cyclonic gyre. The cyclonic gyre stretches from southeast to north-west in the first mode and from the southwest to the northeast in the second mode. The observed modes strongly affect the heat and salt transport in the North Atlantic. In particular, the second mode slows down the westward transport of the warm and saline water from the Mediterranean Sea.

  9. 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.

  10. Vertical plate motions in the West Siberian Basin

    Science.gov (United States)

    Vibe, Yulia

    2014-05-01

    The West Siberian Basin is a sedimentary basin situated between the Ural Mountains and the Siberian Craton. The Basin has experienced several periods of subsidence and uplift since the arrival of the Siberian Traps c. 250 Ma. Although the Basin is extensively explored and hosts large reserves of Oil and Gas, the forces driving the vertical motions are poorly understood. In this work we attempt to analyse the amount, timing and location of subsidence and uplift in the Basin to shed light on the possible causes of these motions. A detailed description of sedimentary layers is published in a number of Soviet-era books and articles and serves as a basis for our research. This data is first converted into sediment grids through time. Subsequently, the sediments, the sediment load and the compaction are taken into account ('backstripping') to produce the depth of the Basin at respective time steps. With this technique we calculate the tectonic component of subsidence. Uncertainties related to uplift events are estimated by the unconformities in the stratigraphic charts. One of the possible driving forces of vertical motions is a change of force balance arising at plate boundaries. Since active plate tectonics have been absent from West Siberia since the formation of the Urengoy and Khodosey Rifts, c. 250Ma, we study the far-field tectonic effects as a potential driving mechanism. Indeed, some of the significant vertical events in the West Siberian Basin coincide with the major tectonic events around Siberia. An example is the spreading in the Arctic (Eurasian Basin) in the Eocene (56 Ma) which was synchronous with initiation of uplift events in the northern part of West Siberia. In the middle Oligocene (33 Ma), the northern and eastern parts of the basin were subjected to uplift as subsidence migrated southwards and the Basin rose above the sea level. This was coincident with the changes of plate motions in the northern North Atlantic and Indo-European collision.

  11. 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...

  12. Port Development and Town Planning in North West England

    Science.gov (United States)

    Newman, Richard

    2013-12-01

    This paper examines the links between the development of harbour facilities and planned towns, especially in the head port area of Carlisle in North West England. Largely based on documentary research and field observation it examines the development of Whitehaven and other Atlantic ports it influenced in Cumberland, Westmorland and north Lancashire. It examines these developments in their international context and shows how they were initiated by local landowners to maximise the output of their estates and to enhance their personal prestige. Beginning in the seventeenth century the paper demonstrates how this tradition of town and harbour foundation continued on into the nineteenth century when it was adopted by corporate concerns, especially railway companies. The paper concludes by highlighting how harbour developments associated with town planning helped to urbanise and stimulate the economy of a previously under-developed area. Two maps identify the locations of the places discussed.

  13. Route Choice by the VLCCS from Middle East Gulf to North Atlantic

    Institute of Scientific and Technical Information of China (English)

    Risto Laulajainen

    2009-01-01

    <正>Three alternatives for round voyages between the Middle East Gulf and North Atlantic,Cape/Cape,Suez/Cape and Suez/Suez(laden/ballast),are compared from actor perspective.Ship owners benefit from long routes when rates are not rising steeply.Refineries minimize logistics costs by selecting short routes.Traders also should opt for them,provided that their investment horizontal equals the laden leg.In the real world,Northwest Europe selects 10 pet Suez and the US Gulf 10 pet Cape.East Coast Canada is route neutral.Cargos from West Africa tilt this equation in favor of the Cape/Cape alternative.

  14. 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.

  15. [West Nile virus infection].

    Science.gov (United States)

    Pérez Ruiz, Mercedes; Gámez, Sara Sanbonmatsu; Clavero, Miguel Angel Jiménez

    2011-12-01

    West Nile virus (WNV) is an arbovirus usually transmitted by mosquitoes. The main reservoirs are birds, although the virus may infect several vertebrate species, such as horses and humans. Up to 80% of human infections are asymptomatic. The most frequent clinical presentation is febrile illness, and neuroinvasive disease can occur in less than 1% of cases. Spain is considered a high-risk area for the emergence of WNV due to its climate and the passage of migratory birds from Africa (where the virus is endemic). These birds nest surrounding wetlands where populations of possible vectors for the virus are abundant. Diagnosis of human neurological infections can be made by detection of IgM in serum and/or cerebrospinal fluid samples, demonstration of a four-fold increase in IgG antibodies between acute-phase and convalescent-phase serum samples, or by detection of viral genome by reverse transcription-polymerase chain reaction (especially useful in transplant recipients). Since WNV is a biosafety level 3 agent, techniques that involve cell culture are restricted to laboratories with this level of biosafety, such as reference laboratories. The National Program for the Surveillance of WNV Encephalitis allows the detection of virus circulation among birds and vectors in areas especially favorable for the virus, such as wetlands, and provides information for evaluation of the risk of disease in horses and humans.

  16. Discourse Between East and West

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The first Chinese-hosted cultural dialogue between the East and the West was held in Nishan, Shandong Province The first Nishan Forum on World Civilizations kicked off on September 26 at Nishan Mountain, 25 km southeast

  17. Warm water events in the southeast Atlantic and their impact on regional and large-scale atmospheric conditions in the CMIP5 model output

    Science.gov (United States)

    Ott, Irena; Lutz, Karin; Rathmann, Joachim; Jacobeit, Jucundus

    2013-04-01

    Two types of El Niño-like events are described in the South Atlantic: the Atlantic Niño in the equatorial Atlantic and the Benguela Niño off the Namibian and Angolan coast. These warm water events are known to be associated with rainfall anomalies at the West and Southwest African coastal region and harm marine ecosystems and fish populations. The two phenomena are handled separately so far, but the identification of warm water events in our study - via similar variabilities of sea surface temperatures (SST) - based on observed SST data (HadISST1.1) as well as global climate model output from CMIP5, involved the definition of an area mean index that includes both Niño types from the Atlantic region. A multi-model ensemble of the CMIP5 output is used to investigate the impact of Atlantic Niño events on regional atmospheric conditions. Based on the Atlantic SST index, composite analyses give information about anomalous precipitation, air pressure, humidity, evaporation, horizontal wind and vertical air motion patterns over the African continent and the South Atlantic. The Atlantic variability mode is similar to the Pacific El Niño system, but more irregular and less intense. However, recent studies show that the Atlantic influences the El Niño Southern Oscillation (ENSO) in the Pacific Ocean by the modification of the Walker and Hadley circulations and associated wind stress, thermocline and SST anomalies, further amplified by the Bjerknes positive feedback. As a result, an Atlantic Niño is followed by a La Niña-like phenomenon in the Pacific area with a lag of six months. In our study, the CMIP5 output is considered with respect to its ability of describing the complex connection between the Atlantic and Pacific variability modes. For that purpose, the inter-ocean teleconnection is studied with correlation analyses of the ensemble members of the CMIP5 output by means of the Atlantic index, the Southern Oscillation (SOI) and the Pacific El Niño indices (Ni

  18. Diversity and distribution of microbial eukaryotes in the deep tropical and subtropical North Atlantic Ocean

    Science.gov (United States)

    Morgan-Smith, Danielle; Clouse, Melissa A.; Herndl, Gerhard J.; Bochdansky, Alexander B.

    2013-08-01

    Employing a combination of 4',6-diamidino-2-phenylindole and fluorescein isothiocyanate (DAPI-FITC) staining and catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH), we distinguished a variety of taxonomic and morphological types of eukaryotic microbes in the central and deep water masses of the tropical and subtropical North Atlantic Ocean. Samples were taken along a transect across the tropical Atlantic, along the equatorial upwelling and into the West-African upwelling region. Samples were collected as deep as 7000 m in the Romanche Fracture Zone within the Mid-Atlantic Ridge. Approximately 50-70% of FISH-identified eukaryotes in deep water masses belong to one of seven groups: kinetoplastids, labyrinthulomycetes, fungi, diplonemids, group II alveolates, MAST 4 (stramenopiles), and an unidentified organism with a peculiar nuclear morphology. A smaller percentage of total eukaryotes was identified in the Central Water, especially in the oxygen minimum zone, than in deep water masses. CARD-FISH probes designed to identify broad taxonomic groups revealed kinetoplastids and fungi were more abundant than noted in previous studies employing 18S rRNA gene clone libraries. Group II alveolates, in contrast, were much less prevalent than previously reported. On a second survey, eukaryotic microbes were enumerated in the deep-sea basins below the North Atlantic subtropical gyre including the Vema Fracture Zone, which is another prominent trench in the Mid-Atlantic Ridge. The abundance of eukaryotes and chlorophyll concentrations were significantly different between the two cruises, which covered very different hydrographic regimes with associated high and low levels of primary production, respectively.

  19. Glacial to Holocene changes in trans-Atlantic Saharan dust transport and dust-climate feedbacks.

    Science.gov (United States)

    Williams, Ross H; McGee, David; Kinsley, Christopher W; Ridley, David A; Hu, Shineng; Fedorov, Alexey; Tal, Irit; Murray, Richard W; deMenocal, Peter B

    2016-11-01

    Saharan mineral dust exported over the tropical North Atlantic is thought to have significant impacts on regional climate and ecosystems, but limited data exist documenting past changes in long-range dust transport. This data gap limits investigations of the role of Saharan dust in past climate change, in particular during the mid-Holocene, when climate models consistently underestimate the intensification of the West African monsoon documented by paleorecords. We present reconstructions of African dust deposition in sediments from the Bahamas and the tropical North Atlantic spanning the last 23,000 years. Both sites show early and mid-Holocene dust fluxes 40 to 50% lower than recent values and maximum dust fluxes during the deglaciation, demonstrating agreement with records from the northwest African margin. These quantitative estimates of trans-Atlantic dust transport offer important constraints on past changes in dust-related radiative and biogeochemical impacts. Using idealized climate model experiments to investigate the response to reductions in Saharan dust's radiative forcing over the tropical North Atlantic, we find that small (0.15°C) dust-related increases in regional sea surface temperatures are sufficient to cause significant northward shifts in the Atlantic Intertropical Convergence Zone, increased precipitation in the western Sahel and Sahara, and reductions in easterly and northeasterly winds over dust source regions. Our results suggest that the amplifying feedback of dust on sea surface temperatures and regional climate may be significant and that accurate simulation of dust's radiative effects is likely essential to improving model representations of past and future precipitation variations in North Africa.

  20. Atlantic hurricane response to geoengineering

    Science.gov (United States)

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

    2015-04-01

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

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

    Directory of Open Access Journals (Sweden)

    J. Park

    2010-03-01

    Full Text Available An energy-conservative metric based on the discrete wavelet transform is applied to assess the relative energy distribution of non-stationary 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 timescales at Key West, while at Pensacola the AMO-dependent changes in temporal event behaviour are less pronounced. Extreme events with increased temporal dynamics are 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.

  2. 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.

  3. 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

  4. Landscape evolution of West Kunlun

    Science.gov (United States)

    Wang, Bin; Chang, Hong

    2010-05-01

    Constituting the northwestern margin of the Tibetan Plateau, the present-day Western Kunlun is a spectacular mountain range, extending from the Pamir Plateau in the west to the Altyn Tagh fault and the Eastern Kunlun Range in the east. Dramatic climate variations have a significant control on the fluvial dissection, glacial erosion and wind transport. The West Kunlun Mountains is one of the key regions for understanding the uplift history of the Plateau and the climate change of Central Asia. The activities of tectonic and erosion make the topography of West Kunlun Mountains complex and varied. However, due to its remote location, there is still limited knowledge about the geomorphologic and geological features in West Kunlun Mountains .This paper tries to figure out the geomorphologic and geological features of this region qualitatively through studying the data of Shuttle Reader Topography Mission (SRTM) and topographic maps by digital elevation models (DEMs) and constructing profiles, aiming to make clear what functions the tectonics and climate exert on the topography of the West Kunlun Mountains. The West Kunlun Mountains, the northwestern margin of the Qinghai-Tibet Plateau, have strong tectonic activities. From south to north,West Kunlun Mountains developed three major faults: Kangxiwar fracture, North West Kunlun fault and Iron Creek fault. At about 25 Ma B.P., the West Kunlun began to uplift, and from about 5 Ma B.P., the West Kunlun began to grow rapidly. By using topographic analyzing software to make more than 10 vertical profiles across the main faults from south to north, it is obvious that there is a height difference between the upper and lower plate fracture, and the elevation of terrain profiles generally decreases from south to north. There is ~4,500m elevation difference between the main ridge of the West Kunlun Mountains out of Kangxiwar (5500-6000m) and the northern foot of the Tarim Basin (1200-1300m). The same progressively decreasing

  5. Dual annual spawning races in Atlantic sturgeon.

    Directory of Open Access Journals (Sweden)

    Matthew T Balazik

    Full Text Available Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus, Acipenseridae populations in the United States were listed as either endangered or threatened under the Endangered Species Act in 2012. Because of the endangered/threatened status, a better understanding of Atlantic sturgeon life-history behavior and habitat use is important for effective management. It has been widely documented that Atlantic sturgeon reproduction occurs from late winter to early summer, varying clinally with latitude. However, recent data show Atlantic sturgeon also spawn later in the year. The group that spawns later in the year seems to be completely separate from the spring spawning run. Recognition of the later spawning season has drastically modified estimates of the population status of Atlantic sturgeon in Virginia. With the combination of new telemetry data and historical documentation we describe a dual spawning strategy that likely occurs in various degrees along most, if not all, of the Atlantic sturgeon's range. Using new data combined with historical sources, a new spawning strategy emerges which managers and researchers should note when determining the status of Atlantic sturgeon populations and implementing conservation measures.

  6. 75 FR 27219 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

    Science.gov (United States)

    2010-05-14

    ... United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications...), Commerce. ACTION: Final rule. SUMMARY: NMFS issues final specifications for the 2010 Atlantic deep- sea red..., the NMFS Assistant Administrator has determined that this rule is consistent with the Atlantic...

  7. 75 FR 49420 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

    Science.gov (United States)

    2010-08-13

    ... United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications In... (TAC) and corresponding fleet days-at-sea (DAS) allocation for the Atlantic deep- sea red crab fishery... the implementing regulations for the Atlantic Deep- Sea Red Crab Fishery Management Plan...

  8. 75 FR 7435 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

    Science.gov (United States)

    2010-02-19

    ... United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications... Atlantic deep-sea red crab fishery, including a target total allowable catch (TAC) and a fleet-wide days-at-sea (DAS) allocation. The implementing regulations for the Atlantic Deep-Sea Red Crab...

  9. 75 FR 35435 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

    Science.gov (United States)

    2010-06-22

    ... United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications In... finalized 2010 specifications for the Atlantic deep-sea red crab fishery, including a target total allowable... Atlantic Deep-Sea Red Crab Fishery Management Plan (FMP) allow NMFS to make an in-season adjustment to...

  10. Life history tactics of Atlantic salmon in Newfoundland

    OpenAIRE

    Gibson, John; Haedrich, Richard

    2006-01-01

    Popular articles about the Atlantic salmon (Salmo salar) usually state that ‘the Atlantic salmon is an anadromous species’, e.g. publications by the Atlantic Salmon Federation (North America), Atlantic Salmon Trust (UK), and WWF (World Wildlife Fund), and the life history is depicted as migration of juveniles from fresh water to the marine environment, with a return to where the fish were born as spawning adults. This article reviews the life history tactics of Atlantic salmon in Newfoundland...

  11. Implications of climate change on flow regime affecting Atlantic salmon

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available The UKCIP02 climate change scenarios (2070–2100 suggest that the UK climate will become warmer (an overall increase of 2.5–3°C, with temperature increases being greater in the summer and autumn than in the spring and winter seasons. In terms of precipitation, winters are expected to become wetter and summers drier throughout the UK. The effect of changes in the future climate on flow regimes are investigated for the Atlantic salmon, Salmo salar, in a case study in an upland UK river. Using a hydraulic modelling approach, flows simulated across the catchment are assessed in terms of hydraulic characteristics (discharge per metre width, flow depths, flow velocities and Froude number. These, compared with suitable characteristics published in the literature for various life stages of Atlantic salmon, enable assessment of habitat suitability. Climate change factors have been applied to meteorological observations in the Eden catchment (north-west England and effects on the flow regime have been investigated using the SHETRAN hydrological modelling system. High flows are predicted to increase by up to 1.5%; yet, a greater impact is predicted from decreasing low flows (e.g. a Q95 at the outlet of the study catchment may decrease to a Q85 flow. Reliability, Resilience and Vulnerability (RRV analysis provides a statistical indication of the extent and effect of such changes on flows. Results show that future climate will decrease the percentage time the ideal minimum physical habitat requirements will be met. In the case of suitable flow depth for spawning activity at the outlet of the catchment, the percentage time may decrease from 100% under current conditions to 94% in the future. Such changes will have implications for the species under the Habitats Directive and for catchment ecological flow management strategies.

  12. 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.)

  13. 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...

  14. Atlantic NAD 83 SLA Baseline Tangents

    Data.gov (United States)

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

  15. Northwest Atlantic Regional Climatology (NCEI Accession 0155889)

    Data.gov (United States)

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

  16. 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 NAD 83 SLA Baseline Points

    Data.gov (United States)

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

  18. Decadal cyclone variability in the North Atlantic

    Energy Technology Data Exchange (ETDEWEB)

    Luksch, U.; Blender, R.; Fraedrich, K. [Meteorological Inst., Univ. of Hamburg (Germany); Raible, C.C. [Climate and Environmental Physics, Physics Inst., Univ. of Bern (Switzerland)

    2005-12-01

    The unstable midlatitude ocean-atmosphere coupling motivates the definition of two decadal regimes with distinct implications for the North Atlantic cyclone variability. Phases with low (high) decadal variability of the North Atlantic Oscillation, which are connected with an annular (sectoral) spatial scale of the geopotential height teleconnection pattern, are identified as a hemispheric (regional) regime. In the hemispheric regime during a positive El Nino/Southern Oscillation (ENSO) index (warm event), the North Atlantic cyclones and the regions of enhanced precipitation shift southward while over northern Europe the cyclone activity and the rainfall are reduced. During the regional regime this impact of ENSO on the Atlantic storm track is extremely small and a clear interpretation over Europe is inhibited. (orig.)

  19. 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...

  20. Atlantic NAD 83 Continental Shelf Boundary (CSB)

    Data.gov (United States)

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

  1. 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...

  2. ENSO components of the Atlantic multidecadal oscillation and their relation to North Atlantic interannual coastal sea level anomalies

    Directory of Open Access Journals (Sweden)

    J. Park

    2012-11-01

    Full Text Available The El Niño Southern Oscillation (ENSO and the Atlantic Multidecadal Oscillation (AMO are known to influence coastal water levels along the east coast of the United States. By identifying empirical orthogonal functions (EOFs which coherently contribute from the Multivariate ENSO Index (MEI to the AMO index (AMOI, we characterize both the expression of ENSO in the unsmoothed AMOI, and coherent relationships between these indices and interannual sea level anomalies at six stations in the Gulf of Mexico and Western North Atlantic. Within the ENSO band (2–7 yr periods the total contribution of MEI to unsmoothed AMOI variability is 79%. Cross correlation suggests that the MEI leads expression of the ENSO signature in the AMOI by six months, consistent with the mechanism of an atmospheric bridge. Within the ENSO band, essentially all of the coupling between the unsmoothed AMOI and sea level anomalies is the result of ENSO expression in the AMOI. At longer periods we find decadal components of sea level anomalies linked to the AMOI at three southern stations (Key West, Pensacola, Charleston, but not at the northern stations (Baltimore, Boston, Portland, with values of coherence ranging from 20 to 50%. The coherence of MEI to coastal sea level anomalies has a different structure and is generally weaker than that of the ENSO expressed AMOI influence, suggesting distinct physical mechanisms are influencing sea level anomalies due to a direct ENSO teleconnection when compared to teleconnections based on ENSO expression in the AMOI. It is expected that applying this analysis to extremes of sea level anomalies will reveal additional influences.

  3. NAO and extreme ocean states in the Northeast Atlantic Ocean

    Science.gov (United States)

    Gleeson, Emily; Gallagher, Sarah; Clancy, Colm; Dias, Frédéric

    2017-02-01

    Large scale atmospheric oscillations are known to have an influence on waves in the North Atlantic. In quantifying how the wave and wind climate of this region may change towards the end of the century due to climate change, it is useful to investigate the influence of large scale oscillations using indices such as the North Atlantic Oscillation (NAO: fluctuations in the difference between the Icelandic low pressure system and the Azore high pressure system). In this study a statistical analysis of the station-based NAO index was carried out using an ensemble of EC-Earth global climate simulations, where EC-Earth is a European-developed atmosphere ocean sea-ice coupled climate model. The NAO index was compared to observations and to projected changes in the index by the end of the century under the RCP4.5 and RCP8.5 forcing scenarios. In addition, an ensemble of EC-Earth driven WAVEWATCH III wave model projections over the North Atlantic was analysed to determine the correlations between the NAO and significant wave height (Hs) and the NAO and extreme ocean states. For the most part, no statistically significant differences were found between the distributions of observed and modelled station-based NAO or in projected distributions of the NAO. Means and extremes of Hs are projected to decrease on average by the end of this century. The 95th percentile of Hs is strongly positively correlated to the NAO. Projections of Hs extremes are location dependent and in fact, under the influence of positive NAO the 20-year return levels of Hs were found to be amplified in some regions. However, it is important to note that the projected decreases in the 95th percentile of Hs off the west coast of Ireland are not statistically significant in one of the RCP4.5 and one of the RCP8.5 simulations (me41, me83) which indicates that there is still uncertainty in the projections of higher percentiles.

  4. 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.

  5. Sedimentary cover deformations in the equatorial Atlantic and their comparison with geophysical fields

    Science.gov (United States)

    Sokolov, S. Yu.

    2017-01-01

    The deformations of the sedimentary cover at near-latitudinal geotraverses west and east of the Mid-Atlantic Ridge in the equatorial part of ocean are compared with potential fields and variations of the V p/ V s attribute at a depth of 470 km. The features of sedimentary cover deformations in abyssal basins are formulated, as well as their differences from the undisturbed bedding of sediments. The elements of chain of phenomena with common spatial manifestations and cause-and-effect relationships have been established, including heterogeneous horizontal movements, which make up macrojointing above "cold" mantle blocks at a depth of 470 km; serpentinization of upper-mantle rocks; the formation of superposed magnetic anomalies; the release of the fluids, which acoustically bleach out the sedimentary sequence in seismic imaging; and decompaction of rocks leading to vertical motions and forced folding. The origin of the Atlantic marginal dislocation zone is explained. The coincidence of the deformation boundary in the equatorial Atlantic with the zero contour line of the V p/ V s attribute is revealed. This coincidence is an indicator of the rheological state of the upper mantle.

  6. 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.

  7. Aridity changes in the Sahel and their relation to Atlantic-Ocean circulation

    Science.gov (United States)

    Stuut, Jan-Berend; Mulitza, Stefan; Zabel, Matthias; Prange, Matthias

    2010-05-01

    Life in the semiarid Sahel belt of tropical North Africa strongly depends on the availability of water and has, at least since the Pliocene, been frequently affected by shifts to more arid climate. A recent example of abrupt droughts occurred in the early 70's and 80's of the last century. Here we present grain-size distribution data, analysed with an end-member modelling algorithm (Weltje 1997) as well as bulk chemical data of a sediment core collected from the continental slope offshore Senegal, covering the last 57 kyr. These data suggest that during this time interval there were several periods where a relatively humid climate changed abruptly to dry conditions. These dry conditions, which lasted up to several millennia, occurred synchronously with cold sea surface temperatures (SSTs) in the North Atlantic and reductions in the meridional overturning circulation in the Atlantic Ocean, suggesting that Atlantic Ocean circulation could be closely related to climate conditions in the Sahel. Climate modeling suggests that this drying is induced by a southward shift of the West African monsoon trough in conjunction with an intensification and southward expansion of the midtropospheric African Easterly Jet.

  8. Uniform climate development between the subtropical and subpolar Northeast Atlantic across marine isotope stage 11

    Directory of Open Access Journals (Sweden)

    J. P. Helmke

    2008-04-01

    Full Text Available Proxy records from a core site off Northwest Africa were generated and compared with data from the subpolar Northeast Atlantic to unravel some main climatic features of interglacial marine isotope stage (MIS 11 (423–362 ka. The records point to an almost 25 kyr lasting full interglacial period during stage 11 that was preceded by a considerably long glacial-interglacial transition (Termination V. Off NW Africa, a strong reduction of terrestrially derived iron input is noted after 420 ka suggesting a pronounced increase in continental humidity and vegetation cover over Northwest Africa. In analogy to the Holocene climate of the region, this early wet phase of MIS 11 was likely associated with enhanced influence of the West African monsoon system on the Saharan-Sahel region which led to both a reduction in trade wind intensity off NW Africa and the formation of sapropel S11 in the Mediterranean Sea. A detailed comparison with data from the subpolar North Atlantic indicates a remarkable coherent timing for the main environmental changes in both regions giving evidence for strong interglacial climate connectivity between the low and high latitude North Atlantic. Although our records of MIS 11 compare well with the Holocene in terms of some major climate characteristics there are distinct differences in the temporal evolution of each peak warm interval. This suggests that care should be taken when using MIS 11 as analogue to forecast future interglacial conditions.

  9. Sea surface height variability in the North East Atlantic from satellite altimetry

    Science.gov (United States)

    Sterlini, Paul; de Vries, Hylke; Katsman, Caroline

    2016-08-01

    Data from 21 years of satellite altimeter measurements are used to identify and understand the major contributing components of sea surface height variability (SSV) on monthly time-scales in the North East Atlantic. A number of SSV drivers is considered, which are categorised into two groups; local (wind and sea surface temperature) and remote (sea level pressure and the North Atlantic oscillation index). A multiple linear regression model is constructed to model the SSV for a specific target area in the North Sea basin. Cross-correlations between candidate regressors potentially lead to ambiguity in the interpretation of the results. We therefore use an objective hierarchical selection method based on variance inflation factors to select the optimal number of regressors for the target area and accept these into the regression model if they can be associated to SSV through a direct underlying physical forcing mechanism. Results show that a region of high SSV exists off the west coast of Denmark and that it can be represented well with a regression model that uses local wind, sea surface temperature and sea level pressure as primary regressors. The regression model developed here helps to understand sea level change in the North East Atlantic. The methodology is generalised and easily applied to other regions.

  10. The Atlantic Inflow through the Barents Sea from the high-resolution simulations

    Science.gov (United States)

    Aksenov, Y.; Bacon, S.; Coward, A. C.; Nurser, A. J. G.

    2009-04-01

    Atlantic Water is an important component of the Arctic Ocean circulation. To study Atlantic Water pathways we used the results of a high-resolution global sea ice-ocean simulations for the period 1985 - 2006. The simulations also included passive tracers and ventilation tracer analysis which demonstrated high ventilation of the Barents Sea at few localized sites. Mode waters of Barents Sea Water were identified: the first mode is formed at the shallow convective sites in the northern Barents Sea and contributes in the formation of the Arctic cold halocline water; the second mode is the source of the Arctic low halocline water and is formed in the southeastern Barents Sea; the third dense mode is formed west of Novaya Zemlya. The mode waters continue into the Eurasian Arctic through the northwestern Barents Sea and along the northern Barents Sea shelf, and, via the other route, through the southeastern Barents Sea and the St.Anna Trough. The formation rates of the mode waters along with the heat ans salt transports through the Barents Sea have been estimated and compared to observations. Keywords Arctic Ocean, Barents Sea, Atlantic Water, mode waters, ocean modelling

  11. ENSO components of the Atlantic Multidecadal Oscillation and their relation to North Atlantic interannual coastal sea level anomalies

    Science.gov (United States)

    Park, J. C.; Dusek, G.

    2012-12-01

    The El Niño Southern Oscillation (ENSO) and the Atlantic Multidecadal Oscillation (AMO) are known to influence coastal water levels along the East Coast of the United States. By identifying empirical orthogonal functions (EOFs) which coherently contribute from the Multivariate ENSO Index (MEI) to the AMO index (AMOI), we characterize both the expression of ENSO in the unsmoothed AMOI, and coherent relationships between these indices and interannual sea level anomalies at six stations in the Gulf of Mexico and western North Atlantic. We find that from 1871-2011, 40 to 50% of unsmoothed AMOI variability is coherent with the MEI at periods between 2.5 and 4 years. When integrated over the ENSO band of periods from 2 to 7 years, the total power contributed from the MEI to AMOI is 79%. Further, cross correlation finds that the MEI leads expression of the ENSO signature in the AMOI by six months. Within the ENSO band, essentially all of the forcing identified between the unsmoothed AMOI and sea level anomalies are the result of ENSO expression in the AMOI. Broadband couplings are centered at 3.2, 2.8 and 2.2 years with varying levels of coherence across the six stations. At longer periods we find decadal components of sea level anomalies linked to the AMOI at three southern stations (Key West, Pensacola, Charleston), but not at the northern stations (Baltimore, Boston, Portland). Coherence of MEI with coastal sea level anomalies has a different structure and is generally weaker than that of the ENSO expressed AMOI influence, suggesting distinct physical mechanisms are influencing sea level anomalies due to a direct ENSO teleconnection when compared to teleconnections based on ENSO expression in the AMOI. The analysis is based on linear systems theory, and it is cautioned that this model is likely insufficient to fully characterize the links and feedbacks of the complex dynamics expressed in the analyzed indices. Nonetheless, within the constraints of the model, the

  12. Examining Pacific and Atlantic Hurricane Stage Duration and Length Since 1980

    Science.gov (United States)

    Wachtel, C. J.; Godek, M. L.

    2015-12-01

    Examining Pacific and Atlantic Hurricane Stage Duration and Length Since 1980Cassidy Wachtel and Melissa L. GodekDepartment of Earth and Atmospheric Sciences, State University of New York College at Oneonta, New York 13820 Abstract:Each year hurricanes impact thousands of people and over time changes in hurricane characteristics, such as intensity and frequency, have been identified. This study aims to examine changes in hurricane stage duration and track length of West Atlantic and eastern North Pacific hurricanes between 1980 and 2013. Category 2 through 5 hurricanes are analyzed as they evolved through the full life cycle of a hurricane (tropical depression to tropical storm to category). The NOAA National Ocean Service hurricane reanalysis datasets are used to identify 286 storms which are statistically analyzed by category for 1) temporal changes in stage duration with time and 2) temporal changes in stage track lengths with time. NOAA Earth System Research Laboratory daily mean composites of variables such as vertical wind shear and sea surface temperatures are then examined to explain the temporal tendencies that may be related to climate change. Preliminary results indicate that category 2, 4 and 5 storms experienced an overall decrease in stage duration since 1980. For storms of these magnitudes, generally more rapid intensification to category has occurred over time. Contrarily, increased stage duration is detected for hurricanes that reached category 3 status, showing that these storms have strengthened more slowly with time. In all categories, a few unique cases occurred that exhibited stage durations greater than 1 standard deviation from the mean of the long term trend. These cases require further scrutiny for the environmental conditions that might explain the anomalous departures. Keywords: Hurricanes, West Atlantic Ocean, North Pacific Ocean, Storm Tracks, Tropical Storm, Tropical Depression, Hurricane Stage

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

    NARCIS (Netherlands)

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

    2002-01-01

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

  14. 75 FR 30483 - Atlantic Highly Migratory Species; Atlantic Shark Management Measures; Amendment 3

    Science.gov (United States)

    2010-06-01

    ... Species; Atlantic Shark Management Measures; Amendment 3; Final Rule #0;#0;Federal Register / Vol. 75 , No... Species; Atlantic Shark Management Measures; Amendment 3 AGENCY: National Marine Fisheries Service (NMFS... management alternatives available to rebuild blacknose sharks and end overfishing of blacknose and...

  15. 77 FR 75896 - Atlantic Highly Migratory Species; 2013 Atlantic Shark Commercial Fishing Season

    Science.gov (United States)

    2012-12-26

    ... Species; 2013 Atlantic Shark Commercial Fishing Season AGENCY: National Marine Fisheries Service (NMFS... the Atlantic commercial shark fisheries (sandbar sharks, non-sandbar large coastal sharks, blue sharks, porbeagle sharks, and pelagic sharks (other than porbeagle and blue sharks), non-blacknose small...

  16. 76 FR 53652 - Atlantic Highly Migratory Species; Atlantic Shark Management Measures

    Science.gov (United States)

    2011-08-29

    ... Species; Atlantic Shark Management Measures AGENCY: National Marine Fisheries Service (NMFS), National... sharks in the family Sphyrnidae (except for Sphyrna tiburo) and oceanic whitetip sharks (Carcharhinus...-427-8503 or by fax: 301-713-1917. SUPPLEMENTARY INFORMATION: The U.S. Atlantic shark fisheries...

  17. 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...

  18. 78 FR 52487 - Atlantic Highly Migratory Species; 2014 Atlantic Shark Commercial Fishing Season

    Science.gov (United States)

    2013-08-23

    ... Species; 2014 Atlantic Shark Commercial Fishing Season AGENCY: National Marine Fisheries Service (NMFS... season for the Atlantic commercial shark fisheries. Quotas would be adjusted as allowable based on any..., fishing opportunities for commercial shark fishermen in all regions and areas. The proposed measures...

  19. 75 FR 22103 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; Atlantic Coastal Shark Fishery

    Science.gov (United States)

    2010-04-27

    ... Management Act Provisions; Atlantic Coastal Shark Fishery AGENCY: National Marine Fisheries Service (NMFS... Atlantic Coastal Sharks (Plan) and that the measures New Jersey has failed to implement and enforce are necessary for the conservation of the shark resource. This determination is consistent with the findings...

  20. 78 FR 70500 - Atlantic Highly Migratory Species; 2014 Atlantic Shark Commercial Fishing Seasons

    Science.gov (United States)

    2013-11-26

    ...; 2014 Atlantic Shark Commercial Fishing Seasons AGENCY: National Marine Fisheries Service (NMFS... for the Atlantic commercial shark fisheries. The quota adjustments are based on over- and/or... for commercial shark fishermen in all regions and areas. These actions could affect...

  1. 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...

  2. 76 FR 65673 - Atlantic Highly Migratory Species; Atlantic Shark Management Measures; Correction

    Science.gov (United States)

    2011-10-24

    ... Species; Atlantic Shark Management Measures; Correction AGENCY: National Marine Fisheries Service (NMFS... several Atlantic shark stocks and announced NMFS' intent to amend the 2006 Consolidated Highly Migratory Species (HMS) Fishery Management Plan (FMP) via the rulemaking process to rebuild these shark stocks...

  3. Atlantic salmon, Salmo salar L. are broadly susceptible to isolates representing the North American genogroups of infectious hematopoietic necrosis virus.

    Science.gov (United States)

    Kurath, G; Winton, J R; Dale, O B; Purcell, M K; Falk, K; Busch, R A

    2016-01-01

    Beginning in 1992, three epidemic waves of infectious hematopoietic necrosis, often with high mortality, occurred in farmed Atlantic salmon Salmo salar L. on the west coast of North America. We compared the virulence of eleven strains of infectious hematopoietic necrosis virus (IHNV), representing the U, M and L genogroups, in experimental challenges of juvenile Atlantic salmon in freshwater. All strains caused mortality and there was wide variation within genogroups: cumulative mortality for five U-group strains ranged from 20 to 100%, four M-group strains ranged 30-63% and two L-group strains varied from 41 to 81%. Thus, unlike Pacific salmonids, there was no apparent correlation of virulence in a particular host species with virus genogroup. The mortality patterns indicated two different phenotypes in terms of kinetics of disease progression and final per cent mortality, with nine strains having moderate virulence and two strains (from the U and L genogroups) having high virulence. These phenotypes were investigated by histopathology and immunohistochemistry to describe the variation in the course of IHNV disease in Atlantic salmon. The results from this study demonstrate that IHNV may become a major threat to farmed Atlantic salmon in other regions of the world where the virus has been, or may be, introduced.

  4. Atlantic salmon, Salmo salar L. are broadly susceptible to isolates representing the North American genogroups of infectious hematopoietic necrosis virus

    Science.gov (United States)

    Kurath, Gael; Winton, James R.; Dale, Ole Bendik; Purcell, Maureen K.; Falk, Knut; Busch, Robert D.

    2016-01-01

    Beginning in 1992, three epidemic waves of infectious hematopoietic necrosis, often with high mortality, occurred in farmed Atlantic salmon Salmo salar L. on the west coast of North America. We compared the virulence of eleven strains of infectious hematopoietic necrosis virus (IHNV), representing the U, M and L genogroups, in experimental challenges of juvenile Atlantic salmon in freshwater. All strains caused mortality and there was wide variation within genogroups: cumulative mortality for five U-group strains ranged from 20 to 100%, four M-group strains ranged 30-63% and two L-group strains varied from 41 to 81%. Thus, unlike Pacific salmonids, there was no apparent correlation of virulence in a particular host species with virus genogroup. The mortality patterns indicated two different phenotypes in terms of kinetics of disease progression and final per cent mortality, with nine strains having moderate virulence and two strains (from the U and L genogroups) having high virulence. These phenotypes were investigated by histopathology and immunohistochemistry to describe the variation in the course of IHNV disease in Atlantic salmon. The results from this study demonstrate that IHNV may become a major threat to farmed Atlantic salmon in other regions of the world where the virus has been, or may be, introduced.

  5. 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…

  6. 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.

  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 medi

  8. 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.

  9. Suggested revision for west mexican archeological sequences.

    Science.gov (United States)

    Long, S V; Taylor, R E

    1966-12-16

    A review of the radiocarbon dates and published and unpublished archeological data from the West Mexican states of Sinaloa, Nayarit, Jalisco, and Colima has resulted in a revised tentative chronology for West Mexico.

  10. 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)

  11. The Atlantic Multi-Decadal Oscillation Climate Impact - Zonal and Meridional Coupling

    Science.gov (United States)

    Werner, Rolf; Kirillov, Andrey; Valev, Dimitar; Atanassov, Atanas; Danov, Dimitar; Guineva, Veneta

    2016-07-01

    The Atlantic multi-decadal oscillation (AMO) shows a period of about 60-70 years. Over the time span from 1860 up to 2014 the AMO has had a strong climate impact on the Northern Hemisphere. The AMO is considered to be related to the Atlantic overturning circulation, but the origin of the oscillation is not fully understood up till now. To study the AMO impact on climate, the Hadcrut4, Crut4 and HadSST3 temperature data sets have been employed in the current study. The influence of the AMO on the zonal and meridional temperature distribution has been investigated in detail. The strongest zonal AMO impact was obtained in the Arctic region. The results indicated that the AMO influence on temperature at Southern latitudes was opposite in phase compared to the temperature influence in the Northern Hemisphere, in agreement with the well known heat transfer phenomenon from South to North Atlantic. In the Northern Hemisphere the strongest AMO temperature impact was found over the Atlantic and America. In the West from American continent, over the Pacific, the AMO impact was the lowest obtained over the whole Northern Hemisphere. The Rocky Mountains and Sierra Madre, connected with it southwards, built up an atmospheric circulation barrier preventing a strong propagation of the AMO temperature signal westerly. The amplitude of the AMO index itself was greater during summer-fall. However stronger AMO influence on the Northern Hemisphere temperatures was found during the fall-winter season, when the differences between the Northern Hemisphere temperatures and the temperatures in the tropics were the greatest.

  12. The Atlantic Water boundary current in the Nansen Basin: Transport and mechanisms of lateral exchange

    Science.gov (United States)

    Vâge, Kjetil; Pickart, Robert S.; Pavlov, Vladimir; Lin, Peigen; Torres, Daniel J.; Ingvaldsen, Randi; Sundfjord, Arild; Proshutinsky, Andrey

    2016-09-01

    Data from a shipboard hydrographic survey near 30°E in the Nansen Basin of the Arctic Ocean are used to investigate the structure and transport of the Atlantic Water boundary current. Two high-resolution synoptic crossings of the current indicate that it is roughly 30 km wide and weakly middepth-intensified. Using a previously determined definition of Atlantic Water, the transport of this water mass is calculated to be 1.6 ± 0.3 Sv, which is similar to the transport of Atlantic Water in the inner branch of the West Spitsbergen Current. At the time of the survey a small anticyclonic eddy of Atlantic Water was situated just offshore of the boundary current. The data suggest that the feature was recently detached from the boundary current, and, due to compensating effects of temperature and salinity on the thermal wind shear, the maximum swirl speed was situated below the hydrographic property core. Two other similar features were detected within our study domain, suggesting that these eddies are common and represent an effective means of fluxing warm and salty water from the boundary current into the interior. An atmospheric low-pressure system transiting south of our study area resulted in southeasterly winds prior to and during the field measurements. A comparison to hydrographic data from the Pacific Water boundary current in the Canada Basin under similar atmospheric forcing suggests that upwelling was taking place during the survey. This provides a second mechanism related to cross-stream exchange of heat and salt in this region of the Nansen Basin.

  13. What caused the 2009 cold event in the Atlantic cold tongue region?

    Science.gov (United States)

    Burmeister, Kristin; Brandt, Peter; Lübbecke, Joke F.

    2016-04-01

    The tropical Atlantic (TA) exhibits sea surface temperature (SST) variability on seasonal to inter-annual time scales. This variability is associated with changes of atmospheric dynamics, linking it to severe flooding or droughts in South America and West Africa. This study investigates processes in the TA that might have caused the extreme cold event in the Atlantic cold tongue (ACT) region in 2009. During boreal spring, a strong negative Atlantic meridional mode event developed in the TA associated with northwesterly wind anomalies along the equator. Contrary to what would be expected from ENSO-like dynamics, these wind anomalies did not lead to a warming in the eastern equatorial Atlantic in boreal summer. Instead, from May to August 2009, an abrupt cooling took place in the ACT region resulting in the coldest August ACT SST on record. In the literature, two processes - equatorial wave reflection and meridional advection of subsurface temperatures - are discussed as potential causes of such an event. Whereas previous studies are mainly based on satellite data, reanalysis products and model output, we here use in situ measurements (data from Argo floats, PIRATA buoys, and TACE moorings, as well as CTD data of various ship cruises) in addition to satellite and reanalysis products to investigate the contribution of both processes to the strong surface cooling in the ACT region in 2009. Results based on the Argo float data confirm previous findings that equatorial wave reflection contributed to the cold event in the ACT region in 2009. They further indicate that higher baroclinic mode waves played an important role. The analysis of in situ and reanalysis temperature and velocity data does not suggest a significant contribution of meridional advection of subsurface temperatures for the onset of the 2009 cold event. The results indicate an asymmetry in the importance of meridional advection for non-ENSO-like cold and warm events with warm events more strongly affected

  14. Iberian Atlantic Margins Group investigates deep structure of ocean margins

    Science.gov (United States)

    The Iberian Atlantic Margins Group; Banda, Enric; Torne, Montserrat

    With recent seismic reflection data in hand, investigators for the Iberian Atlantic Margins project are preparing images of the deep continental and oceanic margins of Iberia. In 1993, the IAM group collected near vertical incidence seismic reflection data over a total distance of 3500 km along the North and Western Iberian Margins, Gorringe Bank Region and Gulf of Cadiz (Figure 1). When combined with data on the conjugate margin off Canada, details of the Iberian margin's deep structure should aid in distinguishing rift models and improve understanding of the processes governing the formation of margins.The North Iberian passive continental margin was formed during a Permian to Triassic phase of extension and matured during the early Cretaceous by rotation of the Iberian Peninsula with respect to Eurasia. From the late Cretaceous to the early Oligocene period, Iberia rotated in a counterclockwise direction around an axis located west of Lisbon. The plate boundary between Iberia and Eurasia, which lies along the Pyrenees, follows the north Spanish marginal trough, trends obliquely in the direction of the fossil Bay of Biscay triple junction, and continues along the Azores-Biscay Rise [Sibuet et al., 1994]. Following the NE-SW convergence of Iberia and Eurasia, the reactivation of the North Iberian continental margin resulted in the formation of a marginal trough and accretionary prism [Boillot et al., 1971].

  15. 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.

  16. 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

  17. 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 d

  18. Upslope deposition of extremely distal turbidites: an example from the Tiburon Rise, west-central Atlantic

    Science.gov (United States)

    Dolan, J.; Beck, C.; Ogawa, Y.

    1989-01-01

    These terrigenous silt and sand turbidities represent an unprecedented example of upslope turbidite deposition in an extremely distral setting. Flow thickness was the dominant control on deposition of these beds, rather than true upslope flow. -from Authors

  19. Assessing sewage impact in a South-West Atlantic rocky shore intertidal algal community.

    Science.gov (United States)

    Becherucci, Maria Eugenia; Santiago, Lucerito; Benavides, Hugo Rodolfo; Vallarino, Eduardo Alberto

    2016-05-15

    The spatial and seasonal variation of the specific composition and community parameters (abundance, diversity, richness and evenness) of the intertidal algal assemblages was studied at four coastal sampling sites, distributed along an environmental gradient from the sewage water outfall of Mar del Plata, Buenos Aires, Argentina. Two of them were located close to the sewage outfall (<800m) (impacted area) and the two other were 8 and 9km distant (non-impacted area). The algal abundance was monthly analyzed from October 2008 to May 2009. The algal assemblages varied according to the pollution gradient in spring, summer and autumn, being autumn the season when the highest difference was observed. Ceramium uruguayense was recognized as an indicator species for the non-impacted areas, while Berkeleya sp. represented an indicator species for the sewage outfall impact. Ulva spp. did not reflect the typical pattern observed for other sewage pollution areas.

  20. 75 FR 17463 - Key West Bank, Key West, Florida; Notice of Appointment of Receiver

    Science.gov (United States)

    2010-04-06

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF THE TREASURY Office of Thrift Supervision Key West Bank, Key West, Florida; Notice of Appointment of Receiver Notice... sole Receiver for Key West Bank, Key West, Florida, (OTS No. 14929) on March 26, 2010. Dated: March...

  1. 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....

  2. 33 CFR 117.622 - West Bay

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false West Bay 117.622 Section 117.622 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Massachusetts § 117.622 West Bay The draw of the West Bay Bridge, mile...

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

    Science.gov (United States)

    WAIS Divide Project Members,; 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.; Chen, Hai; Clow, Gary D.; Cole-Dai, Jihong; Conway, Howard; Fitzpatrick, Joan J.; Hargreaves, Geoffrey; ,

    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.

  4. Atlantic reef fish biogeography and evolution

    Science.gov (United States)

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

    2008-01-01

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

  5. Monazite in Atlantic shore-line features

    Science.gov (United States)

    Dryden, Lincoln; Miller, Glen A.

    1954-01-01

    This report is a survey of present and potential production of monazite from part of the Maryland-Florida section of the Atlantic Coastal Plain. The part of the Coastal Plain covered here is the outer (shore-ward) half. In this area, all the large heavy-mineral placers so far discovered occur in sand bodies that, by their shape, size, orientation, and lithology, appear to be ancient beaches, spits, bars, or dunes. Smaller placers have produced from recent shore-line features. The inner part of the Coastal Plain, to be treated in another report, is underlain generally by older rocks, ranging in age from Cretaceous to older Pleistocene. Only two large heavy-mineral placers are now in production at Trail Ridge, and near Jacksonville, both in Florida. Production is planned for the near future near Yulee, Fla.: in Folkston, Ga.: and at one or two localities in eastern North Carolina. Each of these three will produce monazite as a byproduct; the total new reserve for the three placers is about 33,000 tons of monazite. In large heavy-mineral placers of this type, monazite has not been found to run more than about 1 percent of total heavy minerals. In some large placers, notably Trail Ridge, it is almost or completely lacking. No reason for its sporadic occurrence has been found in this investigation. Two placers of potential economic value have been found by this project in Virginia, one west and one east of Chesapeake Bay. Neither is of promise for monazite production, but if they serve to open up exploration or production in the area, there is a chance for monazite as a byproduct from other placers. A discovery of considerable scientific interest has to do with the occurrence of two different suites of heavy minerals in the Coastal Plain, at least south of Virginia. One, an “older” suite, lacks epidote, hornblende, and garnet; this suite occurs in all older formations and in Pleistocene deposits lying above about 50 or 60 feet above sea level. The other,

  6. Atlantic meridional overturning circulation and the prediction of North Atlantic sea surface temperature

    Science.gov (United States)

    Klöwer, M.; Latif, M.; Ding, H.; Greatbatch, R. J.; Park, W.

    2014-11-01

    The Atlantic Meridional Overturning Circulation (AMOC), a major current system in the Atlantic Ocean, is thought to be an important driver of climate variability, both regionally and globally and on a large range of time scales from decadal to centennial and even longer. Measurements to monitor the AMOC strength have only started in 2004, which is too short to investigate its link to long-term climate variability. Here the surface heat flux-driven part of the AMOC during 1900-2010 is reconstructed from the history of the North Atlantic Oscillation, the most energetic mode of internal atmospheric variability in the Atlantic sector. The decadal variations of the AMOC obtained in that way are shown to precede the observed decadal variations in basin-wide North Atlantic sea surface temperature (SST), known as the Atlantic Multidecadal Oscillation (AMO) which strongly impacts societally important quantities such as Atlantic hurricane activity and Sahel rainfall. The future evolution of the AMO is forecast using the AMOC reconstructed up to 2010. The present warm phase of the AMO is predicted to continue until the end of the next decade, but with a negative tendency.

  7. 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

    2002-01-01

    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 is

  8. The Atlantic Multidecadal Oscillation in models and observations

    NARCIS (Netherlands)

    Frankcombe, L.M.

    2010-01-01

    We use a simplified model of the North Atlantic ocean to study the Atlantic Multidecadal Oscillation (AMO), which is a low-frequency variation found in sea surface temperatures (SST) over the North Atlantic ocean. A mechanism for the AMO has previously been described; here we study the excitation of

  9. 22 CFR 120.31 - North Atlantic Treaty Organization.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false North Atlantic Treaty Organization. 120.31 Section 120.31 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS PURPOSE AND DEFINITIONS § 120.31 North Atlantic Treaty Organization. North Atlantic Treaty Organization (NATO)...

  10. 76 FR 166 - Fresh and Chilled Atlantic Salmon From Norway

    Science.gov (United States)

    2011-01-03

    ... COMMISSION Fresh and Chilled Atlantic Salmon From Norway AGENCY: United States International Trade Commission... on fresh and chilled Atlantic salmon from Norway. SUMMARY: The Commission hereby gives notice that it... and chilled Atlantic salmon from Norway would be likely to lead to continuation or recurrence...

  11. 77 FR 70551 - Highly Migratory Species; Atlantic Shark Management Measures

    Science.gov (United States)

    2012-11-26

    ... Part 635 Highly Migratory Species; Atlantic Shark Management Measures; Proposed Rule #0;#0;Federal...; Atlantic Shark Management Measures AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and... shark stock assessments that were completed from 2009 to 2012. The assessments for Atlantic...

  12. 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...... of The Postsouthern Sense of Place in Contemporary Fiction. William A. Link, Richard J. Milbauer Professor of History at the University of Florida, is the author of Links: My Family in American History....

  13. CARINA: nutrient data in the Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    T. Tanhua

    2009-07-01

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

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

    Science.gov (United States)

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

    2016-10-01

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

  15. Cenozoic uplift on the West Greenland margin: active sedimentary basins in quiet Archean terranes.

    Science.gov (United States)

    Jess, Scott; Stephenson, Randell; Brown, Roderick

    2016-04-01

    The North Atlantic is believed by some authors to have experienced tectonically induced uplift within the Cenozoic. Examination of evidence, onshore and offshore, has been interpreted to imply the presence of kilometre scale uplift across the margins of the Barents Sea, North Sea, Baffin Bay and Greenland Sea. Development of topography on the West Greenland margin (Baffin Bay), in particular, has been subject to much discussion and dispute. A series of low temperature thermochronological (AFT and AHe) studies onshore and interpretation of seismic architecture offshore have suggested uplift of the entire margin totalling ~3km. However, challenges to this work and recent analysis on the opposing margin (Baffin Island) have raised questions about the validity of this interpretation. The present work reviews and remodels the thermochronological data from onshore West Greenland with the aim of re-evaluating our understanding of the margin's history. New concepts within the discipline, such as effect of radiation damage on Helium diffusivity, contemporary modelling approaches and denudational mapping are all utilised to investigate alternative interpretations to this margins complex post rift evolution. In contrast to earlier studies our new approach indicates slow protracted cooling across much of the region; however, reworked sedimentary samples taken from the Cretaceous Nuussuaq Basin display periods of rapid reheating and cooling. These new models suggest the Nuussuaq Basin experienced a tectonically active Cenozoic, while the surrounding Archean basement remained quiet. Faults located within the basin appear to have been reactivated during the Palaeocene and Eocene, a period of well-documented inversion events throughout the North Atlantic, and may have resulted in subaerial kilometre scale uplift. This interpretation of the margin's evolution has wider implications for the treatment of low temperature thermochronological data and the geological history of the North

  16. Tropical Cyclones and Climate Controls in the Western Atlantic Basin during the First Half of the Nineteenth Century

    Science.gov (United States)

    Mock, C. J.; Dodds, S. F.; Rodgers, M. D.; Patwardhan, A.

    2008-12-01

    This study describes new comprehensive reconstructions of individual Western Atlantic Basin tropical cyclones for each year of the first half of the nineteenth century in the Western Atlantic Basin that are directly compatible and supplement the National Hurricane Center's HURDAT (Atlantic basin hurricane database). Data used for reconstructing tropical cyclones come from ship logbooks, ship protests, diaries, newspapers, and early instrumental records from more than 50 different archival repositories in the United States and the United Kingdom. Tropical cyclone strength was discriminated among tropical storms, hurricanes, major hurricanes, and non-tropical lows at least at tropical storm strength. The results detail the characteristics of several hundred storms, many of them being newly documented, and tracks for all storms were mapped. Overall, prominent active periods of tropical cyclones are evident along the western Atlantic Ocean in the 1830s but Caribbean and Gulf coasts exhibit active periods as being more evident in the 1810s and 1820s. Differences in decadal variations were even more pronounced when examining time series of activity at the statewide scale. High resolution paleoclimate and historical instrumental records of the AMO, NAO, ENSO, Atlantic SSTs, West African rainfall, and volcanic activity explain how different modes in these forcing mechanisms may explain some of the multidecadal and interannual variations. The early nineteenth century active hurricane activity appears to be particularly unique in corresponding with a low (negative index) AMO period, and as they relate to particular synoptic-scale patterns in the latter part of the Little Ice Age. Model simulations offer some hypotheses on such patterns, perhaps suggesting increased baroclinic-related storms and a slight later possible shift in the seasonal peak of tropical cyclones for some areas at times. Some years, such as 1806, 1837, 1838, 1842, and 1846 have particularly very active

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

    Science.gov (United States)

    2012-07-31

    ... practical effect on the legal supply chain. Swordfish are monitored for compliance with minimum size... the supply chain and limit NOAA's ability to enforce minimum size requirements. Miscellaneous Comment... Atlantic swordfish quotas and implement the management measures contained in Recommendation...

  18. 78 FR 36685 - Atlantic Highly Migratory Species; 2013 Atlantic Bluefin Tuna Quota Specifications

    Science.gov (United States)

    2013-06-19

    ... discard estimate used to set the specifications is wrong, especially if it is too high and as a result the... the Federal Register, emailing individuals who have subscribed to the Atlantic HMS News...

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

    Science.gov (United States)

    2013-01-18

    .... Receive an update on the Atlantic States Marine Fisheries Communication Group Social Media Workshop. 3... Airport Hotel, 4381 Tanger Outlet Boulevard, North Charleston, SC 29418; telephone: (800) 503-5762 or...

  20. 76 FR 23935 - Atlantic Highly Migratory Species; Atlantic Shark Management Measures

    Science.gov (United States)

    2011-04-29

    ... Species; Atlantic Shark Management Measures AGENCY: National Marine Fisheries Service (NMFS), National..., or selling of hammerhead sharks in the family Sphyrnidae (except for Sphyrna tiburo) and oceanic whitetip sharks (Carcharhinus longimanus) caught in association with ICCAT fisheries. This rule...

  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...

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

    Science.gov (United States)

    2013-02-20

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-08-15

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

  4. 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...

  5. William D. Stevenson: Atlantic Canada's first neurosurgeon.

    Science.gov (United States)

    Mukhida, Karim; Mendez, Ivar

    2007-12-01

    The origins of neurosurgical services in Atlantic Canada are tied to the individual efforts of William D. Stevenson. Born in Hamilton, Ontario, Stevenson completed his senior matriculation in Dunnville, Ontario, before studying medicine at the University of Toronto. He completed the Gallie surgical course in Toronto and then spent 1 year training with Edward Archibald at McGill University. After working for 2 years with the Canadian Mobile Neurosurgical Unit in Europe during the Second World War, Stevenson undertook formal neurosurgical training with Kenneth G. McKenzie, Canada's first neurosurgeon. Stevenson was thereafter recruited to Halifax to start the neurosurgical service at the Victoria General Hospital in January 1948, and he remained head of the division for the next 26 years. His pioneering work laid the foundations for the establishment of a major academic neurosurgical service at Dalhousie University and was crucial for the establishment of neurosurgery in Atlantic Canada. After his retirement, Stevenson moved back to Ontario and began his second career, transferring his passion for neurosurgery to oil painting. His legacy to neurosurgery in Atlantic Canada will be remembered in perpetuity with the annual Neurosurgery Resident Research Award at Dalhousie University, established and named in his honour. This paper focuses on Stevenson's life and work in neurosurgery as Atlantic Canada's first neurosurgeon.

  6. 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

  7. 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.

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

    Science.gov (United States)

    Diasso, Ulrich; Abiodun, Babatunde J.

    2015-12-01

    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.

  9. In Search of Patagonian Dust: Atmospheric Deposition of Micronutrients to the Southern Atlantic

    Science.gov (United States)

    Chance, R.; Baker, A. R.; Jickells, T. D.

    2012-12-01

    as those extracted using an ammonium acetate (pH 4.7) leach. On Carcass island in 2010-2011, median (range in parentheses) dry deposition fluxes of 7 (2-23), 39 (9-90), 3 (0.7-7), 0.2 (0.06-0.5), 3.5 (0.4-15), 0.03 (0.01-0.1), 0.05 (0.01-0.2), 0.9 (0.3-5) and 0.1 (0.01-0.3) nmol m-2 day-1 were observed for soluble iron, aluminium, manganese, vanadium, zinc, titanium, cobalt, nickel and lead respectively. With the exception of vanadium, corresponding fluxes observed in the eastern south Atlantic were typically an order of magnitude lower. Conversely, concentrations of trace metals in rain were higher in the eastern Atlantic than in the west. For example, the volume weighted mean concentration of iron was 1382 nM for samples collected during D357, compared to 634 nM for samples collected on Carcass Island. This is thought to be because rain events were rare and short-lived during cruise D357, while larger volumes of more dilute rain were collected on Carcass Island. During the second year of sampling, volcanic ash from Puyehue-Cordon Caulle eruption in Chile fell on the Falklands. Preliminary results concerning the composition and nutrient flux arising from this are also discussed.

  10. West Nile virus and "poliomyelitis".

    Science.gov (United States)

    Sejvar, James J

    2004-07-27

    West Nile virus (WNV) has recently been associated with a syndrome of acute flaccid paralysis. Most cases of WNV-associated weakness have clinical, histopathologic, and electrophysiologic characteristics indistinguishable from those of poliomyelitis caused by infection with poliovirus. There is debate about the nomenclature of this manifestation of WNV infection. An historical perspective of the term "poliomyelitis" suggests that the term "WNV poliomyelitis" seems appropriate, but members of the neurologic and infectious disease communities should engage in discussion regarding the terminology of this syndrome.

  11. Does reservoir host mortality enhance transmission of West Nile virus?

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    Foppa Ivo M

    2007-05-01

    Full Text Available Abstract Background Since its 1999 emergence in New York City, West Nile virus (WNV has become the most important and widespread cause of mosquito-transmitted disease in North America. Its sweeping spread from the Atlantic to the Pacific coast was accompanied by widespread mortality among wild birds, especially corvids. Only sporadic avian mortality had previously been associated with this infection in the Old World. Here, we examine the possibility that reservoir host mortality may intensify transmission, both by concentrating vector mosquitoes on remaining hosts and by preventing the accumulation of "herd immunity". Results Inspection of the Ross-Macdonald expression of the basic reproductive number (R0 suggests that this quantity may increase with reservoir host mortality. Computer simulation confirms this finding and indicates that the level of virulence is positively associated with the numbers of infectious mosquitoes by the end of the epizootic. The presence of reservoir incompetent hosts in even moderate numbers largely eliminated the transmission-enhancing effect of host mortality. Local host die-off may prevent mosquitoes to "waste" infectious blood meals on immune host and may thus facilitate perpetuation and spread of transmission. Conclusion Under certain conditions, host mortality may enhance transmission of WNV and similarly maintained arboviruses and thus facilitate their emergence and spread. The validity of the assumptions upon which this argument is built need to be empirically examined.

  12. Background NO/x/ mixing ratios in air masses over the North Atlantic Ocean

    Science.gov (United States)

    Helas, G.; Warneck, P.

    1981-08-01

    Measurements of nitrogen oxide concentrations in clean air masses over the North Atlantic Ocean are reported. The measurements were performed on the west coast of Ireland using the NO-O3 chemiluminescence technique with NO2 reduced to NO by chemical converters. The average NO2 mixing ratio for a three-week period is found to be 101 + or 87 pptv, with significantly lower values in pure marine air masses. A diurnal variation is also observed in the marine air, with nighttime values of 37 + or - 6 pptv and average values of 87 + or - 47 pptv. Under such conditions, the NO mixing ratio was immeasurably small, while the excess NO(x), i.e. other nitrogen oxides, is also found to be higher during the day compared to nighttime values of about 70 pptv.

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

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    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.

  14. UK Atlantic Margin Environmental Survey: Introduction and overview of bathyal benthic ecology

    Science.gov (United States)

    Bett, Brian J.

    2001-05-01

    The recent expansion of the Oil and Gas Industry in to the deep waters of the UK Atlantic Frontier prompted the industry and its regulator to reappraise the needs and means of environmental monitoring. In concert, deep-sea academics, specialist contractors, the regulator and the Industry, through the Atlantic Frontier Environmental Network (AFEN), devised and implemented a large-scale environmental survey of the deep waters to the north and west of Scotland. The AFEN-funded survey was carried out during the summers of 1996 and 1998, and involved two steps; an initial sidescan sonar mapping of the survey areas, followed up with direct seabed investigations by coring and photography. This contribution deals with the latter step. Seabed samples were collected to assess sediment type, organic content, heavy metals, hydrocarbons and macrobenthos. Photographic and video observations were employed to provide both 'routine' seabed assessments and to investigate particular sidescan features of note. Although essentially intended as a 'baseline' environmental survey, anthropogenic impacts are already evident throughout the areas surveyed. Indications of the effects of deep-sea trawling were frequently encountered (seabed trawl marks and areas of disturbed sediments), being present in almost all of the areas studied and extending to water depths in excess of 1000 m. Evidence of localised contamination of the seabed by drilling muds was also detected, though background hydrocarbon contamination is predominantly of terrestrial origin or derived from shipping. The benthic ecology of the UK Atlantic Margin is dominated by the marked differences in the hydrography of the Faroe-Shetland Channel (FSC) and the Rockall Trough (RT). Comparatively warm North Atlantic Water is common to both areas; however, in the FSC, cold (subzero) waters occupy the deeper parts of the channel (>600 m). The extreme thermal gradient present on the West Shetland Slope has a substantial influence on the

  15. Distribution of intermediate water masses in the subtropical northeast Atlantic

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    I. Bashmachnikov

    2015-05-01

    Full Text Available This work presents the quantitative study of climatological distributions of mid-depth Source Water Types in the NE Atlantic by the Optimum Multiparameter analysis (OMP, merging a~number of regional results from particular synoptic sections. The cores of the Mediterranean Water (MW, the modified Antarctic Intermediate Water (mAAIW and the Subarctic Intermediate Water (SAIW are detected and spatial variations of their depth/density are obtained: as expected, spreading of the source water types is predominantly isopycnic and follows the major mid-depth circulation patterns. In some areas the turbulent transport should also be considered. The MW in the Atlantic spreads as 3 cores of different density: the upper MW core (northwest of the first transition line between 28° W, 35° N and 14° W, 44° N is found in the neutral density range of 27.65–27.70 kg m−3 and depths of 900–1000 m; the main MW core (northwest of the second transition line between 35° W, 28° N and 10° W, 37° N has neutral density around 27.75 kg m−3 and is found at 1000–1100 m; the lower MW core (southeast of the second transition has neutral density around 27.80 kg m−3 and is found at 1250–1350 m. The upper MW core has comparatively low MW contents (below 30% and is speculated to be transported by the mean flow from the northern Iberian Peninsula and the Bay of Biscay to the northern Azores. The main MW core contains the most of the MW. It primarily originates from the MUC between Cape St. Vincent and Estremadura Promontory, where the strongest local decrease of the topographic β-effect is detected and is transported west by a flow at around 39° N. The lower MW core originates in the Gulf of Cadiz and is translated southwestwards by dominating flows. The SAIW (the core between 27.70 and 27.75 kg m−3 is found to spread south along both slopes of the MAR. The SAIW east of the MAR mixes with the upper and the main MW cores and re-circulates in a cyclonic gyre

  16. Surface winds over West Antarctica

    Science.gov (United States)

    Bromwich, David

    1993-01-01

    Five winter months (April-August 1988) of thermal infrared satellite images were examined to investigate the occurrence of dark (warm) signatures across the Ross Ice Shelf in the Antarctic continent. These features are inferred to be generated by katabatic winds that descend from southern Marie Byrd Land and then blow horizontally across the ice shelf. Significant mass is added to this airstream by katabatic winds blowing from the major glaciers that flow through the Transantarctic Mountains from East Antarctica. These negatively buoyant katabatic winds can reach the northwestern edge of the shelf - a horizontal propagation distance of up to 1,000 km - 14 percent of the time. Where the airstream crosses from the ice shelf to the ice-covered Ross Sea, a prominent coastal polynya is formed. Because the downslope buoyancy force is near zero over the Ross Ice Shelf, the northwestward propagation of the katabatic air mass requires pressure gradient support. The study shows that the extended horizontal propagation of this atmospheric density current occurred in conjunction with the passage of synoptic cyclones over the southern Amundsen Sea. These cyclones can strengthen the pressure gradient in the interior of West Antarctica and make the pressure field favorable for northwestward movement of the katabatic winds from West Antarctica across the ice shelf in a geostrophic direction. The glacier winds from East Antarctica are further accelerated by the synoptic pressure gradient, usually undergo abrupt adjustment beyond the exit to the glacier valley, and merge into the mountain-parallel katabatic air mass.

  17. West Nile Virus and wildlife

    Science.gov (United States)

    Marra, P.P.; Griffing, S.; Caffrey, C.; Kilpatrick, A.M.; McLean, R.; Brand, C.; Saito, E.; Dupuis, A.P.; Kramer, Laura; Novak, R.

    2004-01-01

    West Nile virus (WNV) has spread rapidly across North America, resulting in human deaths and in the deaths of untold numbers of birds, mammals, and reptiles. The virus has reached Central America and the Caribbean and may spread to Hawaii and South America. Although tens of thousands of birds have died, and studies of some bird species show local declines, few regionwide declines can be attributed to WNV. Predicting future impacts of WNV on wildlife, and pinpointing what drives epidemics, will require substantial additional research into host susceptibility, reservoir competency, and linkages between climate, mosquitoes, and disease. Such work will entail a collaborative effort between scientists in governmental research groups, in surveillance and control programs, and in nongovernmental organizations. West Nile virus was not the first, and it will not be the last, exotic disease to be introduced to the New World. Its spread in North America highlights the need to strengthen animal monitoring programs and to integrate them with research on disease ecology.

  18. 78 FR 79061 - Noise Exposure Map Notice; Key West International Airport, Key West, FL

    Science.gov (United States)

    2013-12-27

    ... Federal Aviation Administration Noise Exposure Map Notice; Key West International Airport, Key West, FL... Administration (FAA) announces its determination that the Noise Exposure Maps submitted by Monroe County for the Key West International Airport under the provisions of the Aviation Safety and Noise Abatement Act...

  19. 78 FR 2916 - Special Local Regulation; West Palm Beach Triathlon Championship, Intracoastal Waterway, West...

    Science.gov (United States)

    2013-01-15

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation; West Palm Beach Triathlon... Intracoastal Waterway, in West Palm Beach, Florida, during the West Palm Beach Triathlon Championship, on Saturday, June 1, 2013. Approximately 1,500 participants are anticipated to participate in the...

  20. Mesozoic Source-to-Sink of the African margin of the Equatorial Atlantic

    Science.gov (United States)

    ye, jing; Chardon, Dominique; rouby, delphine; Guillocheau, François; Robin, Cecile; Loparev, Artiom; Huyghe, damien; Dall'Asta, Massimo; Brown, Roderick; wildman, mark; webster, david

    2016-04-01

    The objective of the Transform Source to Sink Project (TS2P) is to link the dynamics of the erosion of the West African Craton to the offshore sedimentary basins of the African margin of the Equatorial Atlantic at geological time scales. This margin, alternating transform and oblique segments from Guinea to Nigeria, shows a strong structural variability in the margin width, continental geology and relief, drainage networks and subsidence/accumulation patterns. We analyzed this system combining onshore geology and geomorphology as well as offshore sub-surface data. We produced paleogeographic maps at the scale of West Africa spanning the continental domain and offshore basins since 200 Ma. Mapping spatial and temporal distribution of domains either in erosion (sources) or in accumulation (sinks) document the impact of the successive rifting of Central and Equatorial Atlantic on the physiography of the area. We use low temperature thermochronology dating along three transects perpendicular to the margin (Guinea, Ivory Coast and Benin) to determine periods and domains of denudation in that framework. We compare these data to the Mesozoic accumulation histories in passive margin basins and discuss their stratigraphic expression according to the type of margin segment they are preserved in. Syn-rift architectures (Early Cretaceous) are largely impacted by transform faults that define sub-basins with contrasted width of crustal necking zone (narrower in transform segments than in oblique/normal segments). During the Late Cretaceous post-rift, sedimentary wedges record a transgression along the all margin. Proximal parts of the sedimentary wedge are preserved in basins developing on segments with wide crustal necking zone while they were eroded away in basins developing on narrow segments. As a difference, the Cenozoic wedge is everywhere preserved across the whole width of the margin.

  1. An 854-Year Tree-Ring Chronology of Scots Pine for South-West Finland

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    Helama Samuli

    2014-04-01

    Full Text Available A near-millennial tree-ring chronology (AD 1147-2000 is presented for south-west Finland and analyzed using dendroclimatic methods. This is a composite chronology comprising samples both from standing pine trees (Pinus sylvestris L. and subfossil trunks as recovered from the lake sediments, with a total sample size of 189 tree-ring sample series. The series were dendrochronologically cross-dated to exact calendar years to portray variability in tree-ring widths on inter-annual and longer scales. Al though the studied chronology correlates statistically significantly with other long tree-ring width chronologies from Finland over their common period (AD 1520-1993, the south-west chronology did not exhibit similarly strong mid-summer temperature or spring/early-summer precipitation signals in comparison to published chronologies. On the other hand, the south-west chronology showed highest correlations to the North Atlantic Oscillation indices in winter/spring months, this association following a dendroclimatic feature common to pine chronologies over the region and adjacent areas. Paleoclimatic comparison showed that tree-rings had varied similarly to central European spring temperatures. It is postulated that the collected and dated tree-ring material could be studied for wood surface reflectance (blue channel light intensity and stable isotopes, which both have recently shown to correlate notably well with summer temperatures.

  2. Pan-African Paleostresses and Reactivation of the Eburnean Basement Complex in Southeast Ghana (West Africa

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    Mahaman Sani Tairou

    2012-01-01

    Full Text Available This faulting tectonics analysis concerns the southernmost segment of the Dahomeyide Orogen and the West-African craton eastern margin in southeast Ghana. The analysis of strike-slip faults in the frontal units of the Dahomeyide Belt indicates that four distinct compressive events (NE-SW, ENE-WSW to E-W, ESE-WNW to SE-NW and SE-NW to SSE-NNW originated the juxtaposition of the Pan-African Mobile Zone and the West-African craton. These paleostress systems define a clockwise rotation of the compressional axis during the structuring of the Dahomeyide Orogen (650–550 Ma. The SE-NW and SSE-NNW to N-S compressional axes in the cratonic domain and its cover (Volta Basin suggest that the reactivation of the eastern edge of the West African craton is coeval with the last stages of the Pan-African tectogenesis in southeast Ghana. An extensional episode expressed as late normal faulting is also recorded in this study. This E-W to SE-NW extension, which is particular to the southernmost part of the Dahomeyide Belt, appears to be post-Pan-African. This extension probably contributed to the formation of a major Jurassic rifting zone that originated the Central Atlantic and the Benue Trough.

  3. The Connemara Fan: a major glacial grounding line fan west of Ireland

    Science.gov (United States)

    McCarron, Stephen; Praeg, Daniel; Monteys, Xavier; Scott, Gill

    2014-05-01

    Glacigenic topography on the mid-shelf (~130-350 m water depth) west of Galway, Ireland appears to have the morphological form, internal architecture and sediments associated with a large glacial grounding-line fan. Seismic data collected in 2009 and 2012 (during the GLAMAR and GATEWAYS 1 campaigns) reveal that the broad, arcuate ridges of the 'Olex moraine' form the landward part of a fan system which prograded beyond the mid-shelf break (defining the outer margin of the 'Clare Platform') westwards into the Porcupine Seabight. The topography is comparable to larger shelf-edge trough-mouth fans found further north along the same margin, however no discernible 'trough' has been identified on the Clare Platform. The ridge and fan topographic assemblage is renamed the 'Connemara Fan' in its entirety, based on its genetic relations and geographic location due west of Connemara, western Ireland. A macrofossil recovered from within a debris flow on the outer fan slope comprised of remobilised plumites dates to ~ 20 ka Cal B.P., indicating sediment reworking downslope following deglacial sediment input to at least that time. The Connemara Fan is the most southerly glacigenic fan identified along the north-east Atlantic margin. Its identification also adds to our knowledge of possibly multiple generations of ice sheets feeding onto the Irish shelf from west-central Ireland and the occurrence of ice sheet geometries and dynamics that evacuated ice, melt-water and sediment (ice streams?) westwards across the Clare Platform during past glaciations.

  4. Abrupt Holocene climate change as an important factor for human migration in West Greenland.

    Science.gov (United States)

    D'Andrea, William J; Huang, Yongsong; Fritz, Sherilyn C; Anderson, N John

    2011-06-14

    West Greenland has had multiple episodes of human colonization and cultural transitions over the past 4,500 y. However, the explanations for these large-scale human migrations are varied, including climatic factors, resistance to adaptation, economic marginalization, mercantile exploration, and hostile neighborhood interactions. Evaluating the potential role of climate change is complicated by the lack of quantitative paleoclimate reconstructions near settlement areas and by the relative stability of Holocene temperature derived from ice cores atop the Greenland ice sheet. Here we present high-resolution records of temperature over the past 5,600 y based on alkenone unsaturation in sediments of two lakes in West Greenland. We find that major temperature changes in the past 4,500 y occurred abruptly (within decades), and were coeval in timing with the archaeological records of settlement and abandonment of the Saqqaq, Dorset, and Norse cultures, which suggests that abrupt temperature changes profoundly impacted human civilization in the region. Temperature variations in West Greenland display an antiphased relationship to temperature changes in Ireland over centennial to millennial timescales, resembling the interannual to multidecadal temperature seesaw associated with the North Atlantic Oscillation.

  5. Population genetics and demographic history of red seaweed, Palmaria palmata, from the Canada–northwest Atlantic

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    Jingjing Li

    2013-05-01

    Full Text Available The paleoclimate change (e.g. the glacial fluctuation in the late Pleistocene played an important role in shaping species’ population genetic structure, geographic distribution patterns, and gradient of diversity and composition. In this study, we sampled eight populations (138 individuals of Palmaria palmata, a commercially and ecologically important red macroalga found on both sides of the North Atlantic coast, aiming to assess the genetic structure and demographic history through the integration of mitochondrial cox2–3 spacer and RAPD variation. Eleven mtDNA cox2–3 haplotypes were detected, one of which (C3 was common and located centrally in a haplotype network. It is shared by all populations and is regarded as ancestral. Two northern populations from the Gulf of St. Lawrence had highest levels of genetic diversity, and were significantly divergent from all other populations. AMOVA showed that highest genetic variation for cox2–3 occurred within populations, while less existed among groups. This was consistent with the results of a STRUCTURE clustering analysis of RAPD data. Our genetic diversity and haplotype network analyses indicated that multiple glacial refugia might have existed for the species along the Canada–north- west Atlantic coast. Furthermore, Bayesian skyline plot analysis based on cox2–3 spacer sequences indicated that population size underwent a slight increase over temporal and spatial scales. This occurred in approximately 0.18–0.13 million years ago. Pairwise genetic distance (K2P between populations from the Gulf of St. Lawrence and the Bay of Fundy was 0.2%, indicating that they diverged from their common ancestor since about 0.36 million years ago. The evidence from our study suggests that climatic oscillations during the late Pleistocene had a drastic influence on the demography and genetic diversity of P. palmata in the Canada–northwest Atlantic.

  6. Decadal changes in North Atlantic atmospheric circulation patterns recorded by sand spits since 1800 CE

    Science.gov (United States)

    Poirier, Clément; Tessier, Bernadette; Chaumillon, Éric; Bertin, Xavier; Fruergaard, Mikkel; Mouazé, Dominique; Noël, Suzanne; Weill, Pierre; Wöppelmann, Guy

    2017-03-01

    Present-day coastal barriers represent around 15% of the world's oceanic shorelines, and play an important role as early warning indicators of environmental change. Among them, wave-dominated barriers are dynamic landforms that tend to migrate landward in response to storms and sea-level change. High rates of sediment supply can locally offset the global retrogradation trend, providing valuable records of past environmental change occurring on transgressive coasts. However, geochronological control limits the temporal resolution of such records to millennial or centennial timescales, and the decadal or even faster response of wave-built barriers to historical climate changes is therefore poorly understood. In this study, we show that shoreline dynamics of sand spits reconstructed from old cartographic documents has been synchronous on both margins of the North Atlantic Ocean since about 1800 CE. Spit growth accelerated drastically during three periods lasting about 15 years, characterised by positive North Atlantic Oscillation (NAO) and negative East Atlantic-West Russia (EA-WR) atmospheric circulation patterns. These changes are in phase with periods of increased volcanic activity. We use a high-resolution wave hindcast (1948-2014 CE) in a reference area to confirm the association between NAO and EA-WR as a proxy for offshore and nearshore wave height and for associated longshore sediment transport (LST) involved in spit growth. A 24-month lagged correlation between sediment transport and volcanic aerosol optical thickness (concentration of ashes in the atmosphere) is observed, suggesting that spit shoreline dynamics at the decadal timescale is partially forced by external climate drivers via cascading effects on atmospheric circulation patterns and wave climate. Our results imply that NAO variability alone is not sufficient to understand the evolution of wave-built coastal environments. The associated sediment record can be used to reconstruct multi

  7. The Sensitivity of African Easterly Waves to Eastern Tropical Atlantic Sea-Surface Temperatures

    Science.gov (United States)

    Druyan, Leonard M.; Fulakeza, Matthew

    2011-01-01

    The results of two regional atmospheric model simulations are compared to assess the influence of the eastern tropical Atlantic sea-surface temperature maximum on local precipitation, transient easterly waves and the West African summer monsoon. Both model simulations were initialized with reanalysis 2 data (US National Center for Environmental Prediction and Department of Energy) on 15 May 2006 and extended through 6 October 2006, forced by synchronous reanalysis 2 lateral boundary conditions introduced four times daily. One simulation uses 2006 reanalysis 2 sea-surface temperatures, also updated four times daily, while the second simulation considers ocean forcing absent the sea-surface temperature maximum, achieved here by subtracting 3 K at every ocean grid point between 0 and 15 N during the entire simulation. The simulation with 2006 sea-surface temperature forcing produces a realistic distribution of June-September mean precipitation and realistic westward propagating swaths of maximum rainfall, based on validation against Tropical Rainfall Measuring Mission (TRMM) estimates. The simulation without the sea-surface temperature maximum produces only 57% of the control June-September total precipitation over the eastern tropical Atlantic and about 83% of the Sahel precipitation. The simulation with warmer ocean temperatures generates generally stronger circulation, which in turn enhances precipitation by increasing moisture convergence. Some local precipitation enhancement is also attributed to lower vertical thermal stability above the warm water. The study shows that the eastern tropical Atlantic sea-surface temperature maximum enhances the strength of transient easterly waves and broadens the spatial extent of associated precipitation. However, large-scale circulation and its interaction with the African continent, and not sea-surface temperatures, control the timing and trajectories of the waves.

  8. North Atlantic migratory bird flyways provide routes for intercontinental movement of avian influenza viruses

    Science.gov (United States)

    Dusek, Robert J.; Hallgrimsson, Gunnar T.; Ip, Hon S.; Jónsson, Jón E.; Sreevatsan, Srinand; Nashold, Sean W.; TeSlaa, Joshua L.; Enomoto, Shinichiro; Halpin, Rebecca A.; Lin, Xudong; Federova, Nadia; Stockwell, Timothy B.; Dugan, Vivien G.; Wentworth, David E.; Hall, Jeffrey S.

    2014-01-01

    Avian influenza virus (AIV) in wild birds has been of increasing interest over the last decade due to the emergence of AIVs that cause significant disease and mortality in both poultry and humans. While research clearly demonstrates that AIVs can move across the Pacific or Atlantic Ocean, there has been no data to support the mechanism of how this occurs. In spring and autumn of 2010 and autumn of 2011 we obtained cloacal swab samples from 1078 waterfowl, gulls, and shorebirds of various species in southwest and west Iceland and tested them for AIV. From these, we isolated and fully sequenced the genomes of 29 AIVs from wild caught gulls (Charadriiformes) and waterfowl (Anseriformes) in Iceland. We detected viruses that were entirely (8 of 8 genomic segments) of American lineage, viruses that were entirely of Eurasian lineage, and viruses with mixed American-Eurasian lineage. Prior to this work only 2 AIVs had been reported from wild birds in Iceland and only the sequence from one segment was available in GenBank. This is the first report of finding AIVs of entirely American lineage and Eurasian lineage, as well as reassortant viruses, together in the same geographic location. Our study demonstrates the importance of the North Atlantic as a corridor for the movement of AIVs between Europe and North America.

  9. Export of Pacific carbon through the Arctic Archipelago to the North Atlantic

    Science.gov (United States)

    Shadwick, E. H.; Thomas, H.; Gratton, Y.; Leong, D.; Moore, S. A.; Papakyriakou, T.; Prowe, A. E. F.

    2011-05-01

    During an east-to-west transect through the Canadian Arctic Archipelago, dissolved inorganic carbon (DIC) and total alkalinity (TA) were measured. The watermass composition throughout the Archipelago is determined using TA and the seawater oxygen isotope fractionation ( δ18O) data, and the carbon characteristics of these waters are examined. The influence of the Mackenzie River is primarily limited to the upper water column in the western Archipelago while the fraction of sea-ice melt water in the surface waters increases eastward with maximum values at the outflows of Jones and Lancaster Sounds. The depth of Pacific-origin upper halocline waters increases eastward through the Archipelago. In the western Archipelago, non-conservative variations in deep water DIC are used to compute a subsurface carbon surplus, which appears to be fueled by organic matter produced in the surface layer and by benthic respiration. The eastward transport of carbon from the Pacific, via the Arctic Archipelago, to the North Atlantic is estimated, and the impact of increased export of sea-ice melt water to the North Atlantic is discussed.

  10. A novel betaproteobacterial agent of gill epitheliocystis in seawater farmed Atlantic salmon (Salmo salar.

    Directory of Open Access Journals (Sweden)

    Elena R Toenshoff

    Full Text Available Epitheliocystis, a disease characterised by cytoplasmic bacterial inclusions (cysts in the gill and less commonly skin epithelial cells, has been reported in many marine and freshwater fish species and may be associated with mortality. Previously, molecular and ultrastructural analyses have exclusively associated members of the Chlamydiae with such inclusions. Here we investigated a population of farmed Atlantic salmon from the west coast of Norway displaying gill epitheliocystis. Although 'Candidatus Piscichlamydia salmonis', previously reported to be present in such cysts, was detected by PCR in most of the gill samples analysed, this bacterium was found to be a rare member of the gill microbiota, and not associated with the observed cysts as demonstrated by fluorescence in situ hybridization assays. The application of a broad range 16 S rRNA targeted PCR assay instead identified a novel betaproteobacterium as an abundant member of the gill microbiota. Fluorescence in situ hybridization demonstrated that this bacterium, tentatively classified as 'Candidatus Branchiomonas cysticola', was the cyst-forming agent in these samples. While histology and ultrastructure of 'Ca. B. cysticola' cysts revealed forms similar to the reticulate and intermediate bodies described in earlier reports from salmon in seawater, no elementary bodies typical of the chlamydial developmental cycle were observed. In conclusion, this study identified a novel agent of epitheliocystis in sea-farmed Atlantic salmon and demonstrated that these cysts can be caused by bacteria phylogenetically distinct from the Chlamydiae.

  11. PBDEs in the atmosphere over the Asian marginal seas, and the Indian and Atlantic oceans

    Science.gov (United States)

    Li, Jun; Li, Qilu; Gioia, Rosalinda; Zhang, Yanlin; Zhang, Gan; Li, Xiangdong; Spiro, Baruch; Bhatia, Ravinder S.; Jones, Kevin C.

    2011-12-01

    Air samples were collected from Jan 16 to Mar 14, 2008 onboard the Oceanic II- The Scholar Ship which navigated an east-west transect from Shanghai to Cape Verde, and polybrominated diphenyl ethers (PBDEs) were analyzed in these samples. PBDE concentrations in the atmosphere over the open seas were influenced by proximity to source areas and land, and air mass origins. The concentrations of Σ 21PBDEs over the East and South China Seas, the Bay of Bengal and the Andaman Sea, the Indian Ocean, and the Atlantic Ocean were 10.8 ± 6.13, 3.22 ± 1.57, 5.12 ± 3.56, and 2.87 ± 1.81 pg m -3, respectively. BDE-47 and -99 were the dominant congeners in all the samples, suggesting that the widely used commercial penta-BDE products were the original sources. Over some parts of Atlantic and Indian Ocean, daytime concentrations of BDE-47 and BDE-99 were higher than the concentrations at night. The strong atmospheric variability does not always coincide with a diurnal cycle, but the variability in air concentrations in such remote areas of the ocean remains strong. No significant trends were found for each of PBDE congener with latitude.

  12. 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.)

  13. Can the name Mugil cephalus (Pisces: Mugilidae) be used for the species occurring in the north western Atlantic?

    Science.gov (United States)

    Pacheco-Almanzar, Eloísa; Simons, James; Espinosa-Pérez, Héctor; Chiappa-Carrara, Xavier; Ibáñez, Ana L

    2016-05-09

    Menezes et al. (2010) show that Mugil cephalus Linnaeus, 1758 is different from Mugil liza Valenciennes 1836, the latter being the mullet found along the Atlantic coast of South America. They also suggest that individuals identified as M. cephalus from the northwest Atlantic could represent a population of M. liza in this region, since they doubt the presence of M. cephalus in waters colder than the ones of the West Indies. In order to clarify the presence of M. cephalus in the northwest Atlantic, this study compares meristic and morphometric measurements of M. cephalus and M. liza from the Gulf of Mexico with those obtained by Menezes et al. (2010) for M. liza from South America and for M. cephalus in the Mediterranean Sea. Results show that there are differences in both morphometric and meristic data between the two species. The morphometric measure that differentiates these species is the distance from the snout to the dorsal fin, which is positioned backwards in M. liza compared with M. cephalus. The body width is consistently greater in M. cephalus than M. liza. The meristic character that discriminates between both species is the number of scales in the longitudinal series that, in M. cephalus, ranges from 38 to 43 while in M. liza between 32 to 39. The information presented in this work confirms the presence of M. cephalus in the Gulf of Mexico and the sympatric presence of M. liza is established, even if its abundance is quite low.

  14. Response of the North Atlantic subpolar gyre to persistent North Atlantic oscillation like forcing

    Energy Technology Data Exchange (ETDEWEB)

    Lohmann, Katja; Bentsen, Mats [Nansen Environmental and Remote Sensing Center, Bergen (Norway); Bjerknes Center for Climate Research, Bergen (Norway); Drange, Helge [Nansen Environmental and Remote Sensing Center, Bergen (Norway); Bjerknes Center for Climate Research, Bergen (Norway); University of Bergen, Geophysical Institute, Bergen (Norway); Nansen-Zhu International Research Center, Beijing (China)

    2009-02-15

    The response of the North Atlantic subpolar gyre (SPG) to a persistent positive (or negative) phase of the North Atlantic oscillation (NAO) is investigated using an ocean general circulation model forced with idealized atmospheric reanalysis fields. The integrations are analyzed with reference to a base-line integration for which the model is forced with idealized fields representing a neutral state of the NAO. In the positive NAO case, the results suggest that the well-known cooling and strengthening of the SPG are, after about 10 years, replaced by a warming and subsequent weakening of the SPG. The latter changes are caused by the advection of warm water from the subtropical gyre (STG) region, driven by a spin-up of the Atlantic meridional overturning circulation (AMOC) and the effect of an anomalous wind stress curl in the northeastern North Atlantic, which counteracts the local buoyancy forcing of the SPG. In the negative NAO case, however, the SPG response does not involve a sign reversal, but rather shows a gradual weakening throughout the integration. The asymmetric SPG-response to the sign of persistent NAO-like forcing and the different time scales involved demonstrate strong non-linearity in the North Atlantic Ocean circulation response to atmospheric forcing. The latter finding indicates that analysis based on the arithmetic difference between the two NAO-states, e.g. NAO+ minus NAO-, may hide important aspects of the ocean response to atmospheric forcing. (orig.)

  15. Modes of winter precipitation variability in the North Atlantic

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-07-01

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

  16. 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.)

  17. Coherent water transport across the South Atlantic

    CERN Document Server

    Wang, Y; Beron-Vera, F J

    2015-01-01

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

  18. Wind Stress Increases Glacial Atlantic Overturning

    Science.gov (United States)

    Muglia, J.; Schmittner, A.

    2015-12-01

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

  19. Environmental History in the American West.

    Science.gov (United States)

    Rothman, Hal K.

    1994-01-01

    Asserts that environmental history is an important component of the history of the American west. Discusses the historiography of the American west in relationship to environmental issues. Concludes that environmental history opened the door for scholars to study the way human beings interact with the physical world around them. (CFR)

  20. PETROCHINA WEST EAST GAS PIPELINE & SALES COMPANY

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ PetroChina West East Gas Pipeline & Sales Company, a regional company directly under PetroChina Company Limited (PetroChina), is responsible for the construction and operation of the West-East Gas Pipeline Project, and the gas marketing and sales of the natural gas market in China.

  1. Paintings in Atlantic Megalithic Art: Barnenez

    OpenAIRE

    Bueno Ramírez, Primitiva; de Balbín Behrmann, Rodrigo; Laporte, Luc; Gouezin, Philippe; Barroso Bermejo, Rosa; Hernanz Gismero, Antonio; Gavira-Vallejo, José M.; Iriarte Cela, Mercedes

    2012-01-01

    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 pan...

  2. Cyclic growth in Atlantic region continental crust

    Science.gov (United States)

    Goodwin, A. M.

    1986-01-01

    Atlantic region continental crust evolved in successive stages under the influence of regular, approximately 400 Ma-long tectonic cycles. Data point to a variety of operative tectonic processes ranging from widespread ocean floor consumption (Wilson cycle) to entirely ensialic (Ampferer-style subduction or simple crustal attenuation-compression). Different processes may have operated concurrently in some or different belts. Resolving this remains the major challenge.

  3. 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...

  4. NEFSC 2003 Atlantic Herring Acoustic/Midwater Trawl Survey (DE0308, 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...

  5. 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...

  6. 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...

  7. NEFSC 1998 Atlantic Herring Acoustic/Midwater Trawl Survey (DE9809, EK500)

    Data.gov (United States)

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

  8. NEFSC 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...

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

    Data.gov (United States)

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

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

    Data.gov (United States)

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

  11. 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...

  12. 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...

  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 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...

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

    Data.gov (United States)

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

  17. 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...

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

    Data.gov (United States)

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

  19. 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

  20. Plankton respiration in the Eastern Atlantic Ocean

    Science.gov (United States)

    Robinson, Carol; Serret, Pablo; Tilstone, Gavin; Teira, Eva; Zubkov, Mikhail V.; Rees, Andrew P.; Woodward, E. Malcolm S.

    2002-05-01

    Concurrent measurements of dark community respiration (DCR), gross production (GP), size fractionated primary production ( 14C PP), nitrogen uptake, nutrients, chlorophyll a concentration, and heterotrophic and autotrophic bacterial abundance were collected from the upper 200 m of a latitudinal (32°S-48°N) transect in the Eastern Atlantic Ocean during May/June 1998. The mean mixed layer respiration rate was 2.5±2.1 mmol O 2 m -3 d -1 ( n=119) for the whole transect, 2.2±1.1 mmol O 2 m -3 d -1 ( n=32) in areas where chlorophyll a was dissolved oxygen consumption, was 0.8 ( n=11). At the time of the study, plankton community respiration exceeded GP in the picoautotroph dominated oligotrophic regions (Eastern Tropical Atlantic [15.5°S-14.2°N] and North Atlantic Subtropical Gyre [21.5-42.5°N]), which amounted to 50% of the stations sampled along the 12,100 km transect. These regions also exhibited high heterotrophic: autotrophic biomass ratios, higher turnover rates of phytoplankton than of bacteria and low f ratios. However, the carbon supply mechanisms required to sustain the rates of respiration higher than GP could not be fully quantified. Future research should aim to determine the temporal balance of respiration and GP together with substrate supply mechanisms in these ocean regions.

  1. 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......, Kangerlussuaq, Sisimiut and Nuuk. They are situated in continuous, discontinuous and sporadic permafrost zones. We will show examples of detoriation of permafrost related to present local scale climate observations and large scale climate and permafrost simulations modeled numerically with the GIPL model driven...... by HIRHAM climate projections for Greenland up to 2075. The engineering modelling is based on a risk assessment methodology based on a flow diagram which classify the risk of permafrost degradation causing settlement and stability problems for buildings and infrastructures based on relatively simple...

  2. Arctic Outflow West Of Greenland: Nine Years Of Volume And Freshwater Transports From Observations In Davis Strait

    Science.gov (United States)

    Curry, B.; Lee, C.; Petrie, B.; Moritz, R. E.; Kwok, R.

    2014-12-01

    Recent Arctic changes suggest alterations in the export of freshwater from the Arctic to the North Atlantic, with conceivable impacts on the Atlantic Meridional Overturning circulation. Approximately 50% of the Arctic outflow exits west of Greenland, traveling through the Canadian Arctic Archipelago (CAA) and into Baffin Bay before crossing Davis Strait. The CAA outflow contributes over 50% of the net southward freshwater outflow through Davis Strait. The remainder is deeper outflow from Baffin Bay, flow from the West Greenland Current and runoff from West Greenland and CAA glaciers. Since September 2004, an observational program in Davis Strait has quantified volume and freshwater transport variability. The year-round program includes velocity, temperature and salinity measurements from 15 moorings spanning the full width (330 km) of the strait accompanied by autonomous Seagliders surveys (average profile separation = 4 km) and autumn ship-based hydrographic sections. Over the shallow Baffin Island and West Greenland shelves, moored instrumentation provides temperature and salinity measurements near the ice-ocean interface. From 2004-2013, the average net volume and liquid freshwater transports are -1.6 ± 0.2 Sv, -94 ± 7 mSv, respectively (salinity referenced to 34.8 and negative indicates southward transport); sea ice contributes an additional -10 ± 1 mSv. Over this period, volume and liquid freshwater transports show significant interannual variability and no clear trends, but a comparison with reanalyzed 1987-90 data indicate a roughly 40% decrease in net southward liquid volume transport and a corresponding an almost 30% decrease in freshwater transport. Connections between the Arctic are also captured, e.g., a unique yearlong Davis Strait freshening event starting September 2009 that was likely driven by an earlier freshening (January 2009 - April/May 2010) in the Canadian Arctic. The Davis Strait autumn 2009 salinity minimum was fresher (by about 0

  3. Anomalous opening of the Equatorial Atlantic due to an equatorial mantle thermal minimum

    Science.gov (United States)

    Bonatti, Enrico

    1996-09-01

    The geology of the Equatorial Atlantic is dominated by a broad east-west megashear belt where a cluster of large fracture zones offsets anomalously deep segments of the Mid-Atlantic Ridge (MAR). The origin and evolution of this megashear region may lie ultimately in an equatorial mantle thermal minimum. The notion of a mantle thermal minimum in the Equatorial Atlantic is supported by an equatorial minimum of zero-age topography, a maximum in mantle shear waves seismic velocity and a minimum in the degree of melting, indicated by the chemistry of MAR basalts and peridotites. This thermal minimum has probably been a stable feature since before the Cretaceous separation of Africa from South America; it caused a pre-opening equatorial continental lithosphere thicker and colder than normal. The Cretaceous Benue Trough in western Africa and the Amazon depression in South America are interpreted as morphostructural depressions created or rejuvenated by strike-slip, transpressional and transtensional tectonics ducing extension of the cold/thick equatorial lithosphere. The oceanic rift propagating northward from the South Atlantic impinged against the equatorial thicker, colder and, therefore, stronger than normal continental, lithosphere that consequently acted as a 'locked zone'. This, and a low magmatic budget due to the cold upper mantle, caused a lower than normal rate of propagation of the oceanic rift into the equatorial belt, with diffuse deformation during mostly amagmatic extension. The thick/cold lithosphere prevented major Cretaceous igneous activity from the St. Helena plume. Eventually initial 'weak' isolated nuclei oceanic lithosphere were emplaced, separated by E-W continent/continent transforms. Opening occurred largely by strike-slip motion along these initial transforms. The consequences were that the Equatorial Atlantic opened prevalently along an E-W direction, in contrast to the N-S opening of the North and South Atlantic, and that sheared continental

  4. 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

  5. Decadal variability in the Eastern North Atlantic

    Science.gov (United States)

    Köllner, Manuela; Klein, Birgit; Kieke, Dagmar; Klein, Holger; Rhein, Monika; Roessler, Achim; Denker, Claudia

    2016-04-01

    The strong warming and salinification of the Eastern North Atlantic starting in the mid 1990s has been attributed to a westward contraction of the subpolar gyre and stronger inflow of waters from the subtropical 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. We examine the decadal variability in the eastern North Atlantic based on Argo data from 2000-2015 and have constructed time series for four water masses (Subpolar Mode Water (SPMW), Intermediate Water (IW), upper Labrador Sea Water (uLSW) and deep Labrador Sea Water (dLSW)) at selected locations along the Northwest European shelf. Data from the Rockall Trough and the Iceland Basin are chosen to represent advective pathways in the subpolar gyre at two major branches of the North Atlantic Current towards the Nordic Seas and the Arctic Ocean. Temporal variability of subtropical waters transported northward along the eastern boundary is studied at Goban Spur around 48°N. The Argo data are extended in time with long-term hydrographic observations such as the Extended Ellet Line data and other climatological sources in the region. For the study of transport fluctuations time series from the RACE (Regional circulation and Global change) program (2012-2015) and predecessor programs have been used. These programs have monitored the subpolar gyre in the western basin and provide time series of transports and hydrographic anomalies from moored instruments at the western flank of the Mid Atlantic Ridge (MAR). First results show that the temperatures and salinities remained at high levels for the upper waters (SPMW and IW) until 2010 and have been decreasing since

  6. CARINA oxygen data in the Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    I. Stendardo

    2009-12-01

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

  7. 77 FR 32914 - Snapper-Grouper Fishery of the South Atlantic; 2012 Recreational Accountability Measure and...

    Science.gov (United States)

    2012-06-04

    ... the South Atlantic; 2012 Recreational Accountability Measure and Closure for South Atlantic Golden... (NOAA), Commerce. ACTION: Temporary rule; closure. SUMMARY: NMFS implements accountability measures...

  8. 78 FR 32995 - Snapper-Grouper Fishery of the South Atlantic; 2013 Recreational Accountability Measure and...

    Science.gov (United States)

    2013-06-03

    ... the South Atlantic; 2013 Recreational Accountability Measure and Closure for South Atlantic Golden... (NOAA), Commerce. ACTION: Temporary rule; closure. SUMMARY: NMFS implements accountability measures...

  9. 78 FR 30779 - Snapper-Grouper Fishery of the South Atlantic; 2013 Recreational Accountability Measure and...

    Science.gov (United States)

    2013-05-23

    ... the South Atlantic; 2013 Recreational Accountability Measure and Closure for South Atlantic Snowy... (NOAA), Commerce. ACTION: Temporary rule; closure. SUMMARY: NMFS implements accountability measures...

  10. Climate and vegetation changes around the Atlantic Ocean resulting from changes in the meridional overturning circulation during deglaciation

    Directory of Open Access Journals (Sweden)

    D. Handiani

    2012-07-01

    Full Text Available The Bølling-Allerød (BA, starting ~ 14.5 ka BP is one of the most pronounced abrupt warming periods recorded in ice and pollen proxies. The leading explanation of the cause of this warming is a sudden increase in the rate of deepwater formation in the North Atlantic Ocean and the resulting effect on the heat transport by the Atlantic Meridional Overturning Circulation (AMOC. In this study, we used the University of Victoria (UVic Earth System-Climate Model (ESCM to run simulations, in which a freshwater perturbation initiated a BA-like warming period. We found that under present climate conditions, the AMOC intensified when freshwater was added to the Southern Ocean. However, under Heinrich event 1 (HE1, ~ 16 ka BP climate conditions, the AMOC only intensified when freshwater was extracted from the North Atlantic Ocean, possibly corresponding to an increase in evaporation or a decrease in precipitation in this region. The intensified AMOC led to a warming in the North Atlantic Ocean and a cooling in the South Atlantic Ocean, resembling the bipolar seesaw pattern typical of the last glacial period.

    In addition to the physical response, we also studied the simulated vegetation response around the Atlantic Ocean region. Corresponding with the bipolar seesaw hypothesis, the rainbelt associated with the Intertropical Convergence Zone (ITCZ shifted northward and affected the vegetation pattern in the tropics. The most sensitive vegetation area was found in tropical Africa, where grass cover increased and tree cover decreased under dry climate conditions. An equal but opposite response to the collapse and recovery of the AMOC implied that the change in vegetation cover was transient and robust to an abrupt climate change such as during the BA period, which is also supported by paleovegetation data. The results are in agreement with paleovegetation records from Western tropical Africa, which also show a reduction in forest cover during this

  11. 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

  12. West Nile virus and the climate.

    Science.gov (United States)

    Epstein, P R

    2001-06-01

    West Nile virus is transmitted by urban-dwelling mosquitoes to birds and other animals, with occasional "spillover" to humans. While the means by which West Nile virus was introduced into the Americas in 1999 remain unknown, the climatic conditions that amplify diseases that cycle among urban mosquitoes, birds, and humans are warm winters and spring droughts. This information can be useful in generating early warning systems and mobilizing timely and the most environmentally friendly public health interventions. The extreme weather conditions accompanying long-term climate change may also be contributing to the spread of West Nile virus in the United States and Europe.

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

    Energy Technology Data Exchange (ETDEWEB)

    Jung, T.

    2000-07-01

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

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

    Science.gov (United States)

    2011-01-14

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

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

    Science.gov (United States)

    2012-12-06

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

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

    Science.gov (United States)

    2010-03-08

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

  17. 75 FR 57235 - Atlantic Highly Migratory Species; Atlantic Shark Management Measures

    Science.gov (United States)

    2010-09-20

    ... Caribbean Sea under authority of the Magnuson-Stevens Act (16 U.S.C. 1811, 16 U.S.C. 1854(f)(3)). The... Atlantic sharks be offloaded with fins naturally attached; and Collecting shark life history information... proactive in management and explore methods to establish more flexible regulations that would consider...

  18. 76 FR 65700 - Atlantic Highly Migratory Species; Advisory Panel for Atlantic Highly Migratory Species Southeast...

    Science.gov (United States)

    2011-10-24

    ... fisheries, related industries, research, teaching, writing, conservation, or management of marine organisms... environmental community active in the conservation and management of Atlantic HMS, and the academic community... requirements of participating in the data and/or assessment workshop, the designee must receive...

  19. 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 a

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

    Science.gov (United States)

    2012-05-29

    ... Species; Atlantic Shark Management Measures AGENCY: National Marine Fisheries Service (NMFS), National... considering the inclusion of Gulf of Mexico blacktip sharks in an amendment to the 2006 Consolidated Highly..., sandbar, and blacknose sharks. A new stock assessment is ongoing for Gulf of Mexico blacktip sharks,...

  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,...

  2. 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...

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

    NARCIS (Netherlands)

    Calder, D.R.; Vervoort, W.

    1998-01-01

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

  4. 75 FR 42378 - Fisheries of the South Atlantic; Southeast Data, Assessment, and Review (SEDAR); South Atlantic...

    Science.gov (United States)

    2010-07-21

    ... conditions, and recommends research and monitoring needs. The assessment is independently peer reviewed at...: August 6, 2010: 12 p.m. - 4 p.m. Assessment panelists will (1) discuss red snapper model base runs, (2... Data, Assessment, and Review (SEDAR); South Atlantic red snapper AGENCY: National Marine...

  5. 33 CFR 166.500 - Areas along the Atlantic Coast.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Areas along the Atlantic Coast. 166.500 Section 166.500 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... Anchorages § 166.500 Areas along the Atlantic Coast. (a) Purpose. Fairways, as described in this section...

  6. 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...

  7. Are North Atlantic Multidecadal SST Anomalies Westward Propagating?

    NARCIS (Netherlands)

    Feng, Qingyi; Dijkstra, Hendrik

    2014-01-01

    The westward propagation of sea surface temperature (SST) anomalies is one of the main characteristics of one of the theories of the Atlantic Multidecadal Oscillation. Here we use techniques from complex network modeling to investigate the existence of the westward propagation in the North Atlantic

  8. Salinity effects on Atlantic sturgeon growth and osmoregulation

    Science.gov (United States)

    The Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus Mitchill, 1815) is an anadromous sturgeon species, yet little is known with regard to its osmoregulatory ability and habitat use at early life stages. In order to examine whether salinity poses a physiological challenge to juvenile Atlantic stur...

  9. 77 FR 10772 - Fresh and Chilled Atlantic Salmon From Norway

    Science.gov (United States)

    2012-02-23

    ... COMMISSION Fresh and Chilled Atlantic Salmon From Norway Determination On the basis of the record \\1... countervailing duty order and antidumping duty order on fresh and chilled Atlantic salmon from Norway would not... from Norway: Investigation Nos. 701-TA-302 and 731-TA-454 (Third Review). Issued: February 17, 2012....

  10. 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.

  11. DOLLY SODS WILDERNESS, WEST VIRGINIA.

    Science.gov (United States)

    Englund, Kenneth J.; Hill, James J.

    1984-01-01

    Coal, the principal mineral resource of the Dolly Sods Wilderness, West Virginia is in at least seven beds of low- to medium-volatile bituminous rank. Of these beds, four are of sufficient thickness, quality, and extent to contain demonstrated coal resources which are estimated to total about 15. 5 million short tons in areas of substantiated coal resource potential. A Small-scale development of the coal resources of the Dolly Sods Wilderness has been by several shallow adits which provided fuel for locomotives during early logging operations and by a one truck mine. All mine entries are now abandoned. Peat, shale, clay, and sandstone, occur in the area but because of remoteness of markets and inaccessability they are not classified as resources in this report. Natural gas may occur in rocks underlying the area, but because of a lack of subsurface information an estimate of resource potential has not been made. No evidence of metallic-mineral resources was found during this investigation.

  12. 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.

  13. 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.

  14. 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.

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

    Science.gov (United States)

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

    2016-04-01

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

  16. A 1700-year history of West African multidecadal sea surface temperature and rainfall variability

    Science.gov (United States)

    Kuhnert, Henning; Stefan, Mulitza; Gesine, Mollenhauer

    2010-05-01

    Tropical Atlantic sea surface temperatures (SST) exert a major influence on the latitudinal position and intensity of the West African Monsoon and the tropical rainbelt. The impact of the Atlantic Multidecadal Oscillation (AMO) in particular has previously been demonstrated, but little information is available beyond the instrumental time period. We have reconstructed summer-fall SST and relative changes in the discharge of the Senegal River from a sediment core off southern Mauritania. Time series of SST and seawater-d18O (a measure of salinity and hence discharge) were estimated from planktonic foraminiferal Mg/Ca and d18O. The records are sufficiently resolved to infer multidecadal variability over the past 1700 years and centennial variability over the past 3300 years. River discharge increases slightly over the entire time series. This can be brought into agreement with the general Sahel drying trend indicated by previous studies, when we assume a southward migration of the rainbelt that leads to locally enhanced rainfall over the southernmost Senegal River catchment area in Guinea. SST cooled by 1-1.5 °C between AD 1250 and 1500, more pronounced and somewhat earlier compared with the North Atlantic mean. Spectral analysis reveals several multidecadal periods (38, ~45 and ~62 years) where SST and Senegal River discharge are tightly coupled and are driven by the AMO. The exception is a 30-year periodicity in discharge that has no counterpart in SST, and is potentially linked to meridional tropical SST gradient anomalies. AMO signatures are present throughout the past 1700 years, but vary in amplitude. The most recent and persistent phase of enhanced AMO variability commences around AD 1250 contemporaneous with the transition from the Medieval Climate Anomaly to the Little Ice Age.

  17. 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%.

  18. Drought May Beckon Bigger West Nile Outbreaks

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_163495.html Drought May Beckon Bigger West Nile Outbreaks Dry environment ... found that epidemics were larger during years of drought. There were also bigger outbreaks in areas that ...

  19. Libraries in West Virginia: MedlinePlus

    Science.gov (United States)

    ... this page: https://medlineplus.gov/libraries/westvirginia.html Libraries in West Virginia To use the sharing features ... enable JavaScript. Bridgeport United Hospital Center Health Sciences Library 327 Medical Park Dr Bridgeport, WV 26330 681- ...

  20. 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 withi

  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 - 2015.In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during the preceding...

  2. 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...

  3. 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...

  4. 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...

  5. West Coast Observing System (WCOS) Temperature Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The West Coast Observing System (WCOS) project provides access to temperature and currents data collected at four of the five National Marine Sanctuary sites,...

  6. 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.

  7. Seafloor Asymmetry in the Atlantic Ocean

    Institute of Scientific and Technical Information of China (English)

    S.S.Gao; K.H.Liu

    2004-01-01

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

  8. Inorganic and stable isotope geochemistry of tropical Atlantic/Caribbean planktonic foraminifera : implications for the reconstruction of upper ocean temperatures and stratification

    OpenAIRE

    Regenberg, Marcus

    2007-01-01

    Planktonic foraminifera from tropical Atlantic and Caribbean sediment-surface samples (0-1 cm) show general westward-directed increasing calcification depths depending on the east-west increase in thermocline depth. Positively related planktonic foraminiferal Mg/Ca and carbonate ion concentration in the Caribbean show well preserved Mg/Ca down to depths about 1.5 km above the lysocline, which equals a carbonate ion concentration of 26-18 µmol/kg. Species-specific calibrations of Mg/Ca with d1...

  9. West Nile virus and the climate

    OpenAIRE

    Epstein, Paul R.

    2001-01-01

    West Nile virus is transmitted by urban-dwelling mosquitoes to birds and other animals, with occasional “spillover” to humans. While the means by which West Nile virus was introduced into the Americas in 1999 remain unknown, the climatic conditions that amplify diseases that cycle among urban mosquitoes, birds, and humans are warm winters and spring droughts. This information can be useful in generating early warning systems and mobilizing timely and the most environmentally friendly public h...

  10. Parasites as biological tags to track an ontogenetic shift in the feeding behaviour of Gadus morhua off West and East Greenland.

    Science.gov (United States)

    Münster, Julian; Klimpel, Sven; Fock, Heino O; MacKenzie, Ken; Kuhn, Thomas

    2015-07-01

    Parasites, being an integral part of every ecosystem and trophically transmitted along the food webs, can provide detailed insights into the structure of food webs and can close the information gap between short-term stomach content analyses and long-term fish otolith analyses. They are useful for tracking ontogenetic shifts in the host's diet, the occurrence of specific organisms or migratory behaviour of their hosts, even in inaccessible environments. In the present study, stomach content analyses and parasitological examinations were performed on 70 Atlantic cod Gadus morhua, one of the most important high-level predators of small fish in the North Atlantic, caught during one research vessel cruise from West and East Greenlandic waters. Analyses revealed significant differences in fish size with higher values for East Greenland (average total length (TL) of 50.5 cm) compared to West Greenland (average TL of 33.3 cm). Clear differences were also present in prey and parasite composition. Crustacea was the main food source for all fish (IRI = 10082.70), while the importance of teleosts increased with fish size. With a prevalence of 85 % in West Greenland and 100 % in East Greenland, Nematoda were the most abundant parasite group. The results indicate an ontogenetic shift in the diet, which are discussed in the context of the common distribution theory, stock dynamics and migratory behaviour.

  11. Deep ocean exchange with west-European shelf seas

    Directory of Open Access Journals (Sweden)

    J. M. Huthnance

    2009-06-01

    Full Text Available We review mechanisms and studies of exchange between the north-east Atlantic and the adjacent shelf sea. Mechanisms include: well-developed summer upwelling and associated filaments off Portugal and north-west Spain giving exchange O(3 m2/s per unit length of shelf; prevailing westerly winds further north driving exchange O(1 m2/s; poleward flow along most of the upper slope with associated secondary circulation O(1 m2/s; meanders and eddies in this poleward flow; eddies shed from slope waters into the Bay of Biscay; local exchanges at shelf spurs and depressions or canyons (e.g. dense-water cascading of order 1 m2/s. Tidal transports are larger; their reversal every six hours makes exchange largely ineffective except where internal tides are large and non-linear, as in the Celtic Sea where solitons carry water with exchange O(1 m2/s. These various physical exchanges amount to an estimated 2–3 m2/s per unit length of shelf, between ocean and shelf; a numerical model estimate is comparable: 2.5×106 m3/s onto and off the shelf from Brittany to Norway. Mixing controls the seasonal thermocline, affecting primary production and hence fluxes and fate of organic matter. Specifically, CO2 take-up by primary production, settling below the thermocline before respiration, and then off-shelf transport, make an effective shelf-sea "pump" (for CO2 from the atmosphere to the deep ocean. However, knowledge of biogeochemical fluxes is generally sparse; there is scope for more measurements, model validation and estimates from models.

  12. Potential seaways across West Antarctica

    Science.gov (United States)

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

    2011-10-01

    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 climate, and would broadly define the de-glacial state, but they may also have left evidence of their existence in the coastal seas they once connected. We show the most likely routes for such seaways, and that a direct seaway between Weddell and Ross seas, which did not pass through the Amundsen Sea sector, is unlikely. Continued ice-loss at present rates would open seaways between Amundsen and Weddell seas (A-W), and Amundsen and Bellingshausen seas (A-B), in around one thousand years. This timescale indicates potential future vulnerability, but also suggests seaways may have opened in recent interglacial periods. We attempt to test this hypothesis using contemporary bryozoan species assemblages around Antarctica, concluding that anomalously high similarity in assemblages in the Weddell and Amundsen seas supports recent migration through A-W. Other authors have suggested opening of seaways last occurred during Marine Isotope Stage 7a (209 ka BP), but we conclude that opening could have occurred in MIS 5e (100 ka BP) when Antarctica was warmer than present and likely contributed to global sea levels higher than today.

  13. 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

  14. 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.

  15. An Anatomy of the 1960s Atlantic Cooling.

    Science.gov (United States)

    Hodson, Dan; Robson, Jon; Sutton, Rowan

    2014-05-01

    North Atlantic Sea Surface Temperatures (SSTs) exhibited pronounced multidecadal variability during the 20th Century. In particular, the North Atlantic SSTs exhibited a rapid warming between 1920 and 1940 followed by a rapid cooling between 1960 and 1980. SSTs outside the North Atlantic display a much smaller level of decadal variability over the 20th Century. This pattern of North Atlantic warming and cooling has been linked to subsequent changes in rainfall over the Sahel and Nordeste Brazil, Summertime North American Climate and Atlantic Hurricane Genesis. Several hypotheses for the rapid 1960s Atlantic cooling have been proposed, including a reduction in northward ocean heat transport due to a reduced Atlantic Meridional Overturning Circulation (AMOC) and the significant rise in anthropogenic sulphur dioxide emissions during the latter half of the 20th century. Here we examine the observed 1960s Atlantic cooling in more detail. We describe the evolution of the rapid cooling by constructing a detailed multivariate anatomy of the cooling period in order to illuminate the possible explanations and mechanisms involved. We show that the observed 1960s cooling began around 1964-68 in the Greenland-Iceland-Norway (GIN) seas, later spreading to the Atlantic Sub Polar Gyre and much of the subtropical Atlantic. This initial cooling of the Sub Polar Gyre is associated with a marked reduction in salinity (the Great Salinity Anomaly). The cooling peaked between 1972-76, extending into the Tropical North Atlantic. This period also saw the development of a significant Winter North-South Dipole Mean Sea Level Pressure dipole pattern reminiscent of a positive NAO (High over the Azores, Low over Iceland). The cooling then retreated back to higher latitudes during 1976:80. Our analysis demonstrates that the cooling of the North Atlantic during the 1960s cannot be understood as a simple thermodynamic response to aerosol induced reductions in shortwave radiation. Dynamical changes

  16. On Universal Telecommunication Service and West China Development

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    This paper aims at studying the relationship between universal telecommunication service and West China development. It, firstly, introduces our country's demands for universal telecommunication service; secondly, analyses the demand of West China development for the universal telecommunication service; thirdly, depicts the development status of telecommunication industry of the west region; fourthly, points out the significance of universal telecommunication service to the west area; and lastly, brings forward the connotation of universal telecommunication service of west area.

  17. Jurassic domes in the North Sea - northern North Atlantic region

    Energy Technology Data Exchange (ETDEWEB)

    Surlyk, F. [Univ. of Copenhagen, Geological Inst., Copenhagen (Denmark)

    1996-12-31

    The stratigraphic and tectonic evolution of the Jurassic of East Greenland, the Norwegian Shelf and the North Sea is remarkably similar. A major Middle Jurassic unconformity occurs in all three areas. In the North Sea it is commonly termed the `Mid-Cimmerian Unconformity` and is characterized by progressive truncation of the underlying section towards a centre at the triple junction between the Central Graben, Viking Graben and Moray Firth. Strata above the unconformity show a progressive Late Aalenian-Early Kimmeridgian onlap in the same direction. These relations have been interpreted as caused by Early Jurassic uplift and of a major thermal dome in the central North Sea, followed by Medial and Late Jurassic rifting, erosion, deflation and transgression of the dome. The East Greenland unconformity shows progressive truncation of underlying strata from south to north, and Bajocian to Callovian onlap in the same direction. The same pattern seems to be developed on the conjugate Norwegian margin. This suggests the possibility that the three unconformities have similar causes for their development. It is proposed that major rift domes formed in the Central North Sea and in the Greenland-Norway seaway in Early Jurassic times. The domes were eroded and gradually deflated during Medial Jurassic times and were finally submerged by the Late Oxfordian-Kimmeridgian. They were associated with volcanism and rifting which was delayed with respect to dome initiation. Roughly contemperaneous domes were present west of Britain, north of the Porcupine Seabight, and in Scania, southern Sweden, as reflected by development of asymmetrical unconformities showing progressive truncation of underlying strata, onlap of overlying Jurassic strata, and associated intrusive and extrusive volcanism. The domes are related to impingement of the heads of transient mantle plumes at the base of the lithosphere. The associated unconformities are thus of non-eustatic nature. Domal uplift and

  18. Quantitative reconstruction of Holocene sea ice and sea surface temperature off West Greenland from the first regional diatom data set

    Science.gov (United States)

    Krawczyk, D. W.; Witkowski, A.; Moros, M.; Lloyd, J. M.; Høyer, J. L.; Miettinen, A.; Kuijpers, A.

    2017-01-01

    Holocene oceanographic conditions in Disko Bay, West Greenland, were reconstructed from high-resolution diatom records derived from two marine sediment cores. A modern data set composed of 35 dated surface sediment samples collected along the West Greenland coast accompanied by remote sensing data was used to develop a diatom transfer function to reconstruct April sea ice concentration (SIC) supported by July sea surface temperature (SST) in the area. Our quantitative reconstruction shows that oceanographic changes recorded throughout the last 11,000 years reflect seasonal interplay between spring (April SIC) and summer (July SST) conditions. Our records show clear correlation with climate patterns identified from ice core data from GISP2 and Agassiz-Renland for the early to middle Holocene. The early Holocene deglaciation of western Greenland Ice Sheet was characterized in Disko Bay by initial strong centennial-scale fluctuations in April SIC with amplitude of over 40%, followed by high April SIC and July SST. These conditions correspond to a general warming of the climate in the Northern Hemisphere. A decrease in April SIC and July SST was recorded during the Holocene Thermal Optimum reflecting more stable spring-summer conditions in Disko Bay. During the late Holocene, high April SIC characterized the Medieval Climate Anomaly, while high July SST prevailed during the Little Ice Age, supporting previously identified antiphase relationship between surface waters in West Greenland and climate in NW Europe. This antiphase pattern might reflect seasonal variations in regional oceanographic conditions and large-scale fluctuations within the North Atlantic Oscillation and Atlantic Meridional Overturning Circulation.

  19. Evolution of the West Siberian Basin

    Energy Technology Data Exchange (ETDEWEB)

    Vyssotski, A.V. [Chevron, 1500 Louisiana Street, Houston (United States); Vyssotski, V.N. [TNK-BP, 1 Arbat St, Moscow 119019 (Russian Federation); Nezhdanov, A.A. [OOO TyumenNIIgiprogas, 2 Vorovskogo Str., Tyumen 625019 (Russian Federation)

    2006-01-01

    The West Siberian Basin is one of the largest intra-cratonic basins of the world and an important hydrocarbon province of Russia. Perhaps the most important geologic event in Siberia was the emplacement of basalts around {approx} 250Ma (i.e. Permo-Triassic boundary) covering an area of about 5x10{sup 6} km{sup 2}. This volcanism may be responsible for a mass extinction that occurred around Permian-Triassic time. The pre-basaltic rifting event was limited to the north-northeastern sector of the basin. Initial basin wide subsidence took place in the Jurassic as a result of which the western part of Siberia became the West Siberian Basin bounded by uplifts to the east and to the west. One of the surprising aspects of the West Siberian Basin is the abundance of sub-vertical faults believed to be result of strike-slip movement. While intra-plate inversions and fault reactivation structures have been observed in many cratons, sub-vertical faults observed in the West Siberian Basin are unique because of their geometries and abundance. The differentiation between the effects of tectonics and eustasy in cratonic basins is simple-the global eustatic signal is basin-wide with regional and local tectonics playing an overprinting role. Thus, the Middle Jurassic-Turonian 1st, 2nd, and 3rd order cycles in the West Siberian Basin were primarily driven by eustasy. The Middle Jurassic-Turonian series can be subdivided into two second-order and 16 third-order transgressive-regressive cycles (within dataset extent). Fourth-order cycles appear to be controlled by delta shifting. Although extensively studied, a number of fundamental questions regarding the origin and evolution of the West Siberian Basin remain unresolved or poorly documented in the literature. [Author].

  20. Origin of Quasi-decadal North Atlantic Oscillation Variability

    Science.gov (United States)

    Reintges, Annika; Latif, Mojib; Park, Wonsun

    2015-04-01

    The North Atlantic Oscillation (NAO) is the leading mode of internal atmospheric variability in the North Atlantic sector. It depicts significant quasi-decadal variability that is well documented, but the underlying mechanism is still under discussion. Other quantities in the North Atlantic sector such as sea surface temperature (SST) exhibit variability on a similar timescale. Here we present results from a global climate model which simulates the quasi-decadal NAO and North Atlantic SST variability consistent with observations. The quasi-decadal NAO variability is suggested to originate from large-scale air-sea interactions, where the Atlantic Meridional Overturning Circulation (AMOC) basically sets the timescale. Wind-driven ocean circulation changes provide a fast positive feedback on North Atlantic SST through anomalous Ekman currents and the establishment of an "intergyre" gyre. A delayed negative feedback on SST is accomplished through surface heat flux-driven changes of the AMOC and associated heat transport. The results stress the importance of both wind-induced and thermohaline-induced changes in the ocean circulation for quasi-decadal climate variability in the North Atlantic sector.

  1. Grizzly West: A Failed Attempt to Reintroduce Grizzly Bears in the Mountain West

    Directory of Open Access Journals (Sweden)

    Douglas M. Richardson

    2016-05-01

    Full Text Available Reviewed: Grizzly West: A Failed Attempt to Reintroduce Grizzly Bears in the Mountain West. By Michael M. Dax. Lincoln, NE: University of Nebraska Press, 2015. x + 289 pp. US$ 37.50. ISBN 978-0-8032-6673-5.

  2. 77 FR 56125 - Approval and Promulgation of Air Quality Implementation Plans; West Virginia; Amendments to West...

    Science.gov (United States)

    2012-09-12

    ..., EPA published a notice of proposed rulemaking (NPR) for West Virginia. 77 FR 10423. The ] NPR proposed... adopted a PSD program under 45 CSR 14, and the program became part of the West Virginia SIP. See 51 FR... review by the Office of Management and Budget under Executive Order 12866 (58 FR 51735, October 4,...

  3. 78 FR 22193 - Special Local Regulations; West Palm Beach Triathlon Championship, Intracoastal Waterway; West...

    Science.gov (United States)

    2013-04-15

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulations; West Palm Beach Triathlon... Palm Beach, Florida, during the West Palm Beach Triathlon Championship, on Saturday, June 1, 2013. Approximately 1,500 participants are anticipated to participate in the triathlon. The special local...

  4. Prevalence of West Nile virus in migratory birds during spring and fall migration

    Science.gov (United States)

    Dusek, R.J.; McLean, R.G.; Kramer, L.D.; Ubico, S.R.; Dupuis, A.P.; Ebel, G.D.; Guptill, S.C.

    2009-01-01

    To investigate the role of migratory birds in the dissemination of West Nile virus (WNV), we measured the prevalence of infectious WNV and specific WNV neutralizing antibodies in birds, principally Passeriformes, during spring and fall migrations in the Atlantic and Mississippi flyways from 2001-2003. Blood samples were obtained from 13,403 birds, representing 133 species. Specific WNV neutralizing antibody was detected in 254 resident and migratory birds, representing 39 species, and was most commonly detected in northern cardinals (Cardinalis cardinalis) (9.8%, N = 762) and gray catbirds (Dumetella carolinensis) (3.2%,N = 3188). West Nile virus viremias were detected in 19 birds, including 8 gray catbirds, and only during the fall migratory period. These results provide additional evidence that migratory birds may have been a principal agent for the spread of WNV in North America and provide data on the occurrence of WNV in a variety of bird species. Copyright ?? 2009 by The American Society of Tropical Medicine and Hygiene.

  5. Holocene cooling and Neoglacial sea ice fluctuations in the subpolar North Atlantic

    Science.gov (United States)

    Mueller, J.; Werner, K.; Stein, R. H.; Moros, M.

    2011-12-01

    The reconstruction of palaeo sea ice coverage in the Arctic realm gained increasing interest throughout the past decades and the approaches to identify ancient sea ice occurrences are manifold. By means of organic geochemical biomarker studies and IRD analyses we reconstruct Holocene sea ice conditions in the subpolar North Atlantic, where the spatial and temporal distribution of sea ice is mainly controlled by the advection of warm Atlantic Water via the West Spitsbergen Current and the export of polar water and sea ice from the Arctic Ocean via the East Greenland Current (Rudels et al., 2005). Variations in the strength of this oceanic circulation regime may either stimulate or reduce the sea ice extent. With high-resolution analyses of sediment cores from the western continental margin of Spitsbergen and the East Greenland shelf we provide new evidence for the highly variable character of the sea ice conditions in this area. The combination of the sea ice proxy IP25 (Belt et al., 2007) with phytoplankton-derived biomarkers (e.g. brassicasterol, dinosterol; Volkman, 2006) enables a reliable reconstruction of sea ice and sea surface conditions, respectively (Müller et al., 2009; 2011). By means of these biomarkers, we identify gradually increasing sea ice occurrences from the Mid to the Late Holocene. These are also traceable in the IRD data and align with the Neoglacial cooling trend. Throughout the past ca. 3,000 years BP we observe a significant short-term variability in the biomarker records, which points to rapid advances and retreats of sea ice at the continental margin of West Spitsbergen. To what extent a seesawing of temperate Atlantic Water advection may account for these sea ice fluctuations requires further investigation. Concurrent variations in Siberian river discharge (Stein et al., 2004) and varying glacier extents in Scandinavia and Spitsbergen (Nesje et al., 2001; Svendsen and Mangerud, 1997), however, strengthen that these fluctuations may be

  6. Interaction between the Pacific and Atlantic storm tracks and its implication on the North Atlantic Oscillation.

    Science.gov (United States)

    Drouard, M.; Rivière, G.; Arbogast, P.

    2012-04-01

    In this study, the connection between the Pacific and Atlantic storm tracks is investigated to better understand the influence of the Pacific flow on the North Atlantic Oscillation (NAO). The type of wave breaking in the North Atlantic area and the phase of the NAO have been shown to depend on the properties of the Pacific atmospheric flow (Franzke et al. 2004; Rivière and Orlanski 2007), but the key ingredients in the Pacific flow that influence the NAO are not well identified. The purpose of this study is to analyse the influence of the Pacific flow on the NAO by performing numerical experiments with the Marshall and Molteni (1993) three-level quasi-geostrophic model and by comparing our results with ECMWF data reanalysis. The NAO, defined by the first EOF of the geopotential height in the North Atlantic area, is well reproduced by long term simulations of the model forced by ERA40 data. Similar properties appear in the observed NAO and simulated NAO, in particular, the nature of the waves breaking (more anticyclonic during positive phase events and more cyclonic during negative phase events), their spatial scale (large-scale waves dominate during positive phase events and small-scale waves dominate during negative phase events) and the presence of a large-scale ridge in the eastern Pacific that reaches its maximum four days before the maximum of the positive phase events. In order to investigate the influence of this ridge onto the NAO, diagnostic tools (such as the refractive index) are first used. Then, different strategies of sensitivity numerical experiments (such as initial-value problems) are considered to confirm the role played by the Pacific ridge.

  7. Atlante project; Progetto atlante. Quadro di riferimento, analisi degli strumenti esistenti, implementazione metodologica e applicazione prototipale

    Energy Technology Data Exchange (ETDEWEB)

    Baratozzi, L.; Cagnoli, P.; Filippi, N.; Gherardi, L.; Montaletti, V.; Poli, G.; Scarelli, M. [Regione Emilia Romagna, Assessorato Territorio, Programmazione e Ambiente, Servizio Paesaggio, Parchi e Patrimonio Naturale, Bologna (Italy); Basili, M.; Battista, A.; Colonna, R.; Del Cellio, R.; Forni, A.; Olivetti, I.; Regina, P.; Zarlenga, F. [ENEA, Divisione Caratterizzazione dell' Ambiente e del Territorio, Centro Ricerche della Casaccia, S. Maria di Galeria, RM (Italy)

    2001-07-01

    This paper presents the Atlante project a joint program of Emilia Romagna region and Italian ENEA based on the concept of substantiality and the most important methods and models used in the territorial planning. [Italian] La redazione del presente volume e' stata articolata in modo da bilanciare, da un lato l'esigenza di rispettare il programma di attivita' previsto nell'ambito della Convenzione fra Regione Emilia Romagna ed ENEA.

  8. Estimation of Atlantic-Mediterranean netflow variability

    Science.gov (United States)

    Guerreiro, Catarina; Peliz, Alvaro; Miranda, Pedro

    2016-04-01

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

  9. Atlantic Hurricane Activity: 1851-1900

    Science.gov (United States)

    Landsea, C. W.

    2001-12-01

    This presentation reports on the second year's work of a three year project to re-analyze the North Atlantic hurricane database (or HURDAT). The original database of six-hourly positions and intensities were put together in the 1960s in support of the Apollo space program to help provide statistical track forecast guidance. In the intervening years, this database - which is now freely and easily accessible on the Internet from the National Hurricane Center's (NHC's) Webpage - has been utilized for a wide variety of uses: climatic change studies, seasonal forecasting, risk assessment for county emergency managers, analysis of potential losses for insurance and business interests, intensity forecasting techniques and verification of official and various model predictions of track and intensity. Unfortunately, HURDAT was not designed with all of these uses in mind when it was first put together and not all of them may be appropriate given its original motivation. One problem with HURDAT is that there are numerous systematic as sell as some random errors in the database which need correction. Additionally, analysis techniques have changed over the years at NHC as our understanding of tropical cyclones has developed, leading to biases in the historical database that have not been addressed. Another difficulty in applying the hurricane database to studies concerned with landfalling events is the lack exact location, time and intensity at hurricane landfall. Finally, recent efforts into uncovering undocumented historical hurricanes in the late 1800s and early 1900s led by Jose Fernandez-Partagas have greatly increased our knowledge of these past events, which are not yet incorporated into the HURDAT database. Because of all of these issues, a re-analysis of the Atlantic hurricane database is being attempted that will be completed in three years. As part of the re-analyses, three files will be made available: {* } The revised Atlantic HURDAT (with six hourly intensities

  10. Political struggle and West Indies cricket

    Directory of Open Access Journals (Sweden)

    Jay R. Mandle

    1996-01-01

    Full Text Available [First paragraph] An Area of Conquest: Popular Democracy and West Indies Cricket Supremacy. HILARY McD BECKLES (ed.. Kingston: Ian Randle, 1995. xviii + 154 pp. (Paper n.p. Liberation Cricket: West Indies Cricket Culture. HILARY McD BECKLES & BRIAN STODDART (eds.. Kingston: Ian Randle, 1995. xii + 403 pp. (Paper n.p. We discovered cricket's importance in the English-speaking Caribbean nearly thirty years ago when we took up our first post in the West Indies. Exploring the Mona campus of the University of the West Indies, we were alarmed to observe so many people who appeared to be hearing-disabled. Wherever we went we found people with ear-pieces who were slightly distracted and at the same time prone to violent mood swings, ranging from the depths of despair to enormous elation. Uncertain about the meaning of what we observed, but reluctant, as newcomers, to reveal our ignorance of public health problems in the region, we delayed inquiring about hearing disabilities until we could confide our concerns to a trusted friend. At first convulsed with laughter, she finally recovered sufficiently to assure us that the people of the West Indies did not suffer disproportionately from hearing loss. Rather, the large numbers of people with ear-pieces were listening to a cricket test match!

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

    Directory of Open Access Journals (Sweden)

    K. Ljung

    2007-05-01

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

  12. The Two Branches of the Recirculation of Atlantic Water in Fram Strait

    Science.gov (United States)

    von Appen, Wilken-Jon; Schauer, Ursula; Hattermann, Tore; Albretsen, Jon

    2016-04-01

    The Fram Strait between Greenland and Svalbard is one of the two gateways by which warm Atlantic Water enters the Arctic Ocean providing oceanic heat. The West Spitsbergen Current advects the warm water northward in the eastern Fram Strait. However, only some of this water stays in the boundary current and enters the Arctic Ocean. Another part leaves the boundary current and flows westward across Fram Strait before turning southward in the East Greenland Current. This recirculation of Atlantic Water corresponds with the ice edge in Fram Strait and the two likely depend on each other. Here we present results from a high resolution regional numerical model that shows the recirculation to consist of two branches. The northern branch depends on eddy fluxes while the southern branch exhibits less high frequency variability. We also present a compilation of different observational data in the center of Fram Strait around 0°EW that give insight into the structure of the southern recirculation branch near the ice edge. A glider section resolves the small horizontal scale over which the geostrophic flow occurs. Several meridional CTD sections capture the differences and similarities between different summers. Moorings and Argo floats provide information in winter as well. These observations are compared to the representation of the recirculation in the numerical model. We show that the southern recirculation occurs over a small horizontal distance of about 20km in the vicinity of 79°N and is significantly stronger in winter than in summer. While there is cold freshwater at the surface north of the front, the temperature down to 500m is much higher in the recirculation than further south.

  13. Occurrence and characteristics of mesoscale eddies in the tropical northeast Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    F. Schütte

    2015-12-01

    Full Text Available Coherent mesoscale features (referred to here as eddies in the tropical northeast Atlantic (between 12–22° N and 15–26° W are examined and characterised. The eddies' surface signatures are investigated using 19 years of satellite derived sea level anomaly (SLA data. Two automated detection methods are applied, the geometrical method based on closed streamlines around eddy cores, and the Okubo–Weiß method based on the relation between vorticity and strain. Both methods give similar results. Mean eddy surface signatures of SLA, sea surface temperature (SST and salinity (SSS are obtained from composites of all snapshots around identified eddy cores. Anticyclones/cyclones are associated with elevation/depression of SLA and enhanced/reduced SST and SSS patterns. However, about 20 % of all detected anticyclones show reduced SST and reduced SSS instead. These kind of eddies are classified as anticyclonic mode-water eddies (ACMEs. About 146 ± 4 eddies per year are identified (52 % cyclones, 39 % anticylones, 9 % ACMEs with rather similar mean radii of about 56 ± 12 km. Based on concurrent in-situ temperature and salinity profile data (from Argo float, shipboard and mooring data inside of the three eddy types, their distinct differences in vertical structure is determined. Most eddies are generated preferentially in boreal summer and along the West African coast at three distinct coastal headland region and carry South Atlantic Central Water that originates from the northward transport within the Mauretania coastal current system. Westward eddy propagation (on average about 3.00 ± 2.15 km d−1 is confined to distinct corridors with a small meridional deflection dependent on the eddy type (anticyclones – equatorward, cyclones – poleward, ACMEs – no deflection. Heat and salt flux out of the coastal region and across the Cap Verde Frontal Zone, which separates the shadow zone from the ventilated gyre, are calculated.

  14. Occurrence and characteristics of mesoscale eddies in the tropical northeastern Atlantic Ocean

    Science.gov (United States)

    Schütte, Florian; Brandt, Peter; Karstensen, Johannes

    2016-05-01

    Coherent mesoscale features (referred to here as eddies) in the tropical northeastern Atlantic Ocean (between 12-22° N and 15-26° W) are examined and characterized. The eddies' surface signatures are investigated using 19 years of satellite-derived sea level anomaly (SLA) data. Two automated detection methods are applied, the geometrical method based on closed streamlines around eddy cores, and the Okubo-Weiß method based on the relation between vorticity and strain. Both methods give similar results. Mean eddy surface signatures of SLA, sea surface temperature (SST) and sea surface salinity (SSS) anomalies are obtained from composites of all snapshots around identified eddy cores. Anticyclones/cyclones are identified by an elevation/depression of SLA and enhanced/reduced SST and SSS in their cores. However, about 20 % of all anticyclonically rotating eddies show reduced SST and reduced SSS instead. These kind of eddies are classified as anticyclonic mode-water eddies (ACMEs). About 146 ± 4 eddies per year with a minimum lifetime of 7 days are identified (52 % cyclones, 39 % anticyclones, 9 % ACMEs) with rather similar mean radii of about 56 ± 12 km. Based on concurrent in situ temperature and salinity profiles (from Argo float, shipboard, and mooring data) taken inside of eddies, distinct mean vertical structures of the three eddy types are determined. Most eddies are generated preferentially in boreal summer and along the West African coast at three distinct coastal headland regions and carry South Atlantic Central Water supplied by the northward flow within the Mauretanian coastal current system. Westward eddy propagation (on average about 3.00 ± 2.15 km d-1) is confined to distinct zonal corridors with a small meridional deflection dependent on the eddy type (anticyclones - equatorward, cyclones - poleward, ACMEs - no deflection). Heat and salt fluxes out of the coastal region and across the Cape Verde Frontal Zone, which separates the shadow zone from

  15. Does the Fukushima NPP disaster affect the caesium activity of North Atlantic Ocean fish?

    Directory of Open Access Journals (Sweden)

    G. Kanisch

    2013-08-01

    Full Text Available Fillet samples of marine fish collected from the East/West Greenland currents (GC and from the Baltic Sea (BS have been investigated by gamma-ray spectrometry within the regular German monitoring programme. In samples of the second half of 2011, 134Cs traces have been detected that are suggested to originate from the Fukushima fallout that was deposited in March/April 2011 over the northern North Atlantic and accumulated by fish. The radionuclide 134Cs (half-life 2 yr was indeed detected with quite small activities at about 0.0036 Bq kg−1 w.w. Existing box models describing the transport of Cs within seawater boxes of the northeast Atlantic allowed for estimation of 134Cs contributions from other sources, i.e. from the Chernobyl fallout and from discharges by the two major European nuclear reprocessing plants; both were negligible around Greenland, while for the Chernobyl fallout a small 134Cs background contribution to BS fish was estimated. Model results confirmed the level of 134C measured in BS fish and showed its maximum to have occurred in winter 2011/2012 followed by a continuous decrease. It was also determined that 134Cs activity, but not that of 134Cs, showed a significant negative correlation with sampling depth (150–400 m of GC fish; this strengthens our Fukushima fallout assumption. As a result, the Fukushima fallout in these sea areas only marginally enhanced (GC: 4%; BS: 0.1% pre-Fukushima levels of individual dose rates received by human fish consumers; the addition was around 0.001 μSv following the consumption of 10 kg of fish per year, which is not expected to cause concern according to present guidelines for radiation protection.

  16. Ocean station data collected using bottle casts from ALMIRANTE SALDANHA From Northwest Atlantic and Southwest Atlantic Ocean from 30 October 1980 to 21 August 1982 (NODC Accession 9000164)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Ocean station data were collected using seechi disk, meteorological sensors, and bottle casts in the Northwest Atlantic Ocean (limit-40 W) and Southwest Atlantic...

  17. Atmospheric transmission of North Atlantic Heinrich events

    Science.gov (United States)

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

    1999-01-01

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

  18. Population structure of Atlantic Mackerel (Scomber scombrus)

    DEFF Research Database (Denmark)

    Jansen, Teunis; Gislason, Henrik

    2013-01-01

    between the North Sea and Celtic Sea, which indicates that the two spawning components may be connected by straying individuals. This finding is based on unique larvae samples collected before the collapse of North Sea component, thus showing that the exchange is not a recent phenomenon due...... to the collapse. The analyses of old as well as more recent age distributions show that strong year classes spread into other areas where they spawn as adults (“twinning”). Our findings are in accordance with the lack of solid evidence for stock separation from previous analyses of tagging data, genetics...... 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...

  19. Searching for the Onset of Seafloor Spreading West of Galicia: Wide-Angle Seismic Constraints

    Science.gov (United States)

    Davy, R. G.; Minshull, T. A.; Bayrakci, G.; Bull, J. M.; Sawyer, D. S.; Klaeschen, D.; Papenberg, C. A.; Reston, T. J.; Shillington, D. J.; Ranero, C.; Zelt, C. A.

    2014-12-01

    Rifting and the subsequent breakup of continental lithosphere has given rise to the magma-poor Galicia Bank rifted margin in the North Atlantic Ocean. Hyperextension of continental crust is observed at the deep Galicia margin (west of Spain) and has been accommodated by the rotation of continental fault blocks, which are underlain by the S-reflector, an interpreted detachment fault, which has exhumed serpentinized mantle peridotite. West of these features is the enigmatic Peridotite Ridge (PR) which has been suggested to delimit the western extent of the ocean-continent transition. An outstanding question at this margin is where unequivocal oceanic crust begins, with little existing data to constrain this boundary. We present results from a 160-km-long wide-angle seismic profile, which encompasses the S-reflector to the east, the PR, and the unidentified basement west of the PR. This profile consists of 32 OBS/H recording wide angle seismic data from coincident multichannel seismic surveying. First-arrival travel time tomography models of the crustal velocity structure were produced using two algorithms, with the best fit model having a RMS travel time misfit of 38ms, a χ2 of 0.99 and strong correlation with the structure observed in seismic reflection images. East of the PR, the 3.0-3.5 kms-1 velocity contours match top of crust and the S-reflector generally lies between the 6.0-6.5 kms-1 velocity contours, giving a crustal thickness of 1.5-3.5 km and an average velocity gradient of 0.75 s-1. Similarly, west of the PR we observe a basement layer which is 2.0-4.0 km thick and has an average velocity gradient of 0.72 s-1. High velocity gradients, an absence of velocities typical of oceanic layer 3 and no clear mantle reflections suggest the continued presence of exhumed, serpentinized mantle peridotite west of the PR, which could be analogous to the large expanses of mantle peridotite exposed at the seafloor on the flanks of the ultra-slow Southwest Indian ridge.

  20. Redescription of Liza bandialensis (Teleostei: Mugilidae) with an identification key to mullet species of Eastern Central Atlantic.

    Science.gov (United States)

    Trape, Sébastien; Harrison, Ian J; Diouf, Papa Samba; Durand, Jean-Dominique

    2012-02-01

    Liza bandialensis Diouf 1991 is redescribed because previous descriptions have not been in well-distributed publications and have lacked sufficient detail or reference to voucher specimens. The description provided here is based on specimens from the Sine Saloum estuary, Senegal (West Africa), from where the species was originally described. The distinctness of the species is confirmed both by meristic and molecular criteria. L. bandialensis presents a unique combination of characters with a low number of scales in the longitudinal series (32-33), 10.5-12 transverse scale rows, and distinctly yellowish dorsal, anal, and caudal fins. The currently known distribution of L. bandialensis includes coastal waters of Senegal, Gambia and Guinea Bissau. Finally, we provide a morphological identification key for the sixteen species of Mugilidae species occurring along the eastern central Atlantic coast of Africa.

  1. 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.

  2. 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.

  3. 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......, and it is used when none of the others can be used. It seems that some of the tense suffixes i.e. past (-sima, perfective, perfect, preterite) and future (-ler, begin, be about to, near future) originally had a more or less concrete aspectual meanings and have developed into more abstract tense meanings...... 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...

  4. 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...

  5. Atlantic City, New Jersey Tsunami Forecast Grids for MOST Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Atlantic City, New Jersey Forecast Model Grids provides bathymetric data strictly for tsunami inundation modeling with the Method of Splitting Tsunami (MOST)...

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

    Data.gov (United States)

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

  7. Physiography for the Mid-Atlantic Coastal Plain

    Data.gov (United States)

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

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

    Data.gov (United States)

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

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

    Science.gov (United States)

    Sudarskis, Michel

    1983-01-01

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

  10. Subcropping Geology for the Mid-Atlantic Coastal Plain

    Data.gov (United States)

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

  11. 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...

  12. Economic Assessment of the Atlantic Coast Horseshoe Crab Fishery

    Data.gov (United States)

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

  13. Outer Continental Shelf Lease Blocks - Atlantic Region NAD83

    Data.gov (United States)

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

  14. 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...

  15. 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...

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

    Science.gov (United States)

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

    2016-09-01

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

  17. Hydroclimatology of Extreme Precipitation and Floods Originating from the North Atlantic Ocean

    Science.gov (United States)

    Nakamura, Jennifer

    from the tropical Atlantic Ocean and the Gulf of Mexico. The typical flow conditions are governed by an anomalous semi-stationary ridge situated east of the US East Coast, which steers the moisture and converges it into the Ohio Valley. Significantly, the moisture path common to all the 20 cases studied here as well as the case of April 2011 is distinctly different from the normal path of Atlantic moisture during spring, which occurs further west. It is shown further that the Ohio basin moisture convergence responsible for the floods is caused primarily by the atmospheric circulation anomaly advecting the climatological mean moisture field. Transport and related convergence due to the covariance between moisture anomalies and circulation anomalies are of secondary but non-negligible importance. The importance of atmospheric circulation anomalies to floods is confirmed by conducting a similar analysis for a series of winter floods on the River Eden in northwest England.

  18. 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

  19. Introduction to the Mid-Atlantic Education Review

    Directory of Open Access Journals (Sweden)

    Kevin Crouse

    2013-04-01

    Full Text Available The Mid-Atlantic Education Review is a peer-reviewed, online journal that provides a forum for studies pertaining to educational issues of interest to educators and researchers in the Mid-Atlantic region. The Review publishes articles that contribute to the knowledge base of researchers, policy-makers, teachers, and administrators. To appeal to a broad educational audience, articles cover a spectrum in their level of analysis, subject focus, and methodological approach.

  20. Introduction to the Mid-Atlantic Education Review

    OpenAIRE

    Kevin Crouse

    2013-01-01

    The Mid-Atlantic Education Review is a peer-reviewed, online journal that provides a forum for studies pertaining to educational issues of interest to educators and researchers in the Mid-Atlantic region. The Review publishes articles that contribute to the knowledge base of researchers, policy-makers, teachers, and administrators. To appeal to a broad educational audience, articles cover a spectrum in their level of analysis, subject focus, and methodological approach.

  1. North Atlantic Treaty Organization, the United States, and International Legitimacy

    Science.gov (United States)

    2014-05-22

    8. 42Following the signing of the Treaty of Versailles in 1919, the Albanian State was created but with only one-half of the Albanian population...NORTH ATLANTIC TREATY ORGANIZATION, THE UNITED STATES, AND INTERNATIONAL LEGITIMACY A Monograph by MAJ Mark Van Gelder...North Atlantic Treaty Organization, The United States, and International Legitimacy 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT

  2. Remote acoustic monitoring of North Atlantic right whales (Eubalaena glacialis) reveals seasonal and diel variations in acoustic behavior.

    Science.gov (United States)

    Matthews, Leanna P; McCordic, Jessica A; Parks, Susan E

    2014-01-01

    Remote acoustic monitoring is a non-invasive tool that can be used to study the distribution, behavior, and habitat use of sound-producing species. The North Atlantic right whale (Eubalaena glacialis) is an endangered baleen whale species that produces a variety of stereotyped acoustic signals. One of these signals, the "gunshot" sound, has only been recorded from adult male North Atlantic right whales and is thought to function for reproduction, either as reproductive advertisement for females or as an agonistic signal toward other males. This study uses remote acoustic monitoring to analyze the presence of gunshots over a two-year period at two sites on the Scotian Shelf to determine if there is evidence that North Atlantic right whales may use these locations for breeding activities. Seasonal analyses at both locations indicate that gunshot sound production is highly seasonal, with an increase in the autumn. One site, Roseway West, had significantly more gunshot sounds overall and exhibited a clear diel trend in production of these signals at night. The other site, Emerald South, also showed a seasonal increase in gunshot production during the autumn, but did not show any significant diel trend. This difference in gunshot signal production at the two sites indicates variation either in the number or the behavior of whales at each location. The timing of the observed seasonal increase in gunshot sound production is consistent with the current understanding of the right whale breeding season, and our results demonstrate that detection of gunshots with remote acoustic monitoring can be a reliable way to track shifts in distribution and changes in acoustic behavior including possible mating activities.

  3. 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

  4. 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 (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.

  5. Remote acoustic monitoring of North Atlantic right whales (Eubalaena glacialis reveals seasonal and diel variations in acoustic behavior.

    Directory of Open Access Journals (Sweden)

    Leanna P Matthews

    Full Text Available Remote acoustic monitoring is a non-invasive tool that can be used to study the distribution, behavior, and habitat use of sound-producing species. The North Atlantic right whale (Eubalaena glacialis is an endangered baleen whale species that produces a variety of stereotyped acoustic signals. One of these signals, the "gunshot" sound, has only been recorded from adult male North Atlantic right whales and is thought to function for reproduction, either as reproductive advertisement for females or as an agonistic signal toward other males. This study uses remote acoustic monitoring to analyze the presence of gunshots over a two-year period at two sites on the Scotian Shelf to determine if there is evidence that North Atlantic right whales may use these locations for breeding activities. Seasonal analyses at both locations indicate that gunshot sound production is highly seasonal, with an increase in the autumn. One site, Roseway West, had significantly more gunshot sounds overall and exhibited a clear diel trend in production of these signals at night. The other site, Emerald South, also showed a seasonal increase in gunshot production during the autumn, but did not show any significant diel trend. This difference in gunshot signal production at the two sites indicates variation either in the number or the behavior of whales at each location. The timing of the observed seasonal increase in gunshot sound production is consistent with the current understanding of the right whale breeding season, and our results demonstrate that detection of gunshots with remote acoustic monitoring can be a reliable way to track shifts in distribution and changes in acoustic behavior including possible mating activities.

  6. 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

  7. Non-lethal approach identifies variability of δ15N values in the fin rays of Atlantic Goliath Grouper, Epinephelus itajara

    Directory of Open Access Journals (Sweden)

    Orian E. Tzadik

    2015-06-01

    Full Text Available The Atlantic Goliath Grouper, Epinephelus itajara, is critically endangered throughout its range but has begun to show initial signs of recovery in Florida state waters. As the population continues to rebound, researchers face a pressing need to fill the knowledge gaps about this iconic species. Here, we examined the δ15N isotopic records in fin rays collected from Atlantic Goliath Grouper, and related changes of isotopic ratios over time to life history characteristics. Fin-ray analysis was used as a non-lethal technique to sample individuals from two locations at similar latitudes from the west and east coasts of Florida, USA. δ15N data were acquired by mechanically separating the annuli of each fin ray and then analyzing the material in an Irradiance Elemental Analyzer Mass Spectrometer. The δ15N values were consistent among individuals within populations from each coast of Florida, and mirrored the expected changes over the lives of the fish. Overall, differences were found between δ15N values at juvenile life history phases versus adult phases, but the patterns associated with these differences were unique to each coastal group. We demonstrated, for the first time, that δ15N values from fin rays can be used to assess the life histories of Atlantic Goliath Grouper. The non-lethal strategies outlined here can be used to acquire information essential to the management of species of concern, such as those that are threatened or endangered.

  8. Non-lethal approach identifies variability of δ15N values in the fin rays of Atlantic Goliath Grouper, Epinephelus itajara

    Science.gov (United States)

    Goddard, Ethan A.; Hollander, David J.; Koenig, Christopher C.; Stallings, Christopher D.

    2015-01-01

    The Atlantic Goliath Grouper, Epinephelus itajara, is critically endangered throughout its range but has begun to show initial signs of recovery in Florida state waters. As the population continues to rebound, researchers face a pressing need to fill the knowledge gaps about this iconic species. Here, we examined the δ15N isotopic records in fin rays collected from Atlantic Goliath Grouper, and related changes of isotopic ratios over time to life history characteristics. Fin-ray analysis was used as a non-lethal technique to sample individuals from two locations at similar latitudes from the west and east coasts of Florida, USA. δ15N data were acquired by mechanically separating the annuli of each fin ray and then analyzing the material in an Irradiance Elemental Analyzer Mass Spectrometer. The δ15N values were consistent among individuals within populations from each coast of Florida, and mirrored the expected changes over the lives of the fish. Overall, differences were found between δ15N values at juvenile life history phases versus adult phases, but the patterns associated with these differences were unique to each coastal group. We demonstrated, for the first time, that δ15N values from fin rays can be used to assess the life histories of Atlantic Goliath Grouper. The non-lethal strategies outlined here can be used to acquire information essential to the management of species of concern, such as those that are threatened or endangered. PMID:26082864

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

    Science.gov (United States)

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

    2016-08-01

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

  10. Atlantic effects on recent decadal trends in global monsoon

    Science.gov (United States)

    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 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.

  11. 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...

  12. Current velocity and hydrographic observations in the Southwestern North Atlantic Ocean: Subtropical Atlantic Climate Studies (STACS), 1989 (NCEI 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...

  13. 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.

  14. An overview of chemosynthetic symbioses in bivalves from the North Atlantic and Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    S. Duperron

    2012-11-01

    Full Text Available Deep-sea bivalves found at hydrothermal vents, cold seeps and organic falls are sustained by chemosynthetic bacteria which 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, East America, the Gulf of Mexico, and from hydrothermal vents on the Mid-Atlantic Ridge. In parallel, numerous more easily accessible shallow marine species were studied. We here provide a summary of the current knowledge available on chemosymbiotic bivalves in the area ranging west-to-east from the Gulf of Mexico to Marmara Sea, and north-to-south from the Arctic to the Gulf of Guinea. Characteristics of symbioses in 51 species from the area are summarized for each of the five bivalve families documented to harbor chemosynthetic symbionts (Mytilidae, Vesicomyidae, Solemyidae, Thyasiridae and Lucinidae, and compared among families with special emphasis on ecology, life cycle, and connectivity. Chemosynthetic symbioses are a major adaptation to ecosystems and habitats exposed to reducing conditions, yet 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 for a better assessment of bivalve symbioses diversity in order to evaluate the capacities of these remarkable ecological and evolutionary units to withstand environmental change

  15. 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.

  16. Recent space shuttle observations of the South Atlantic anomaly and the radiation belt models

    Science.gov (United States)

    Konradi, A.; Badhwar, G. D.; Braby, L. A.

    1994-01-01

    Active ingredients consisting of Tissue Equivalent Proportional Counter (TEPC) and a Proton and Heavy Ion Detector (PHIDE) have been carried on a number of Space Shuttle flights. These instruments have allowed us to map out parts of the South Atlantic Particle Anomaly (SAA) and to compare some of it's features with predictions of the AP-8 energetic proton flux models. We have observed that consistent with the generally observed westward drift of the surface features of the terrestial magnetic field of the SAA has moved west by about 6.9 degrees longitude between the epoch year 1970 of the AP-8 solar maximum model and the Space Shuttle observations made twenty years later. However, calculations indicate that except for relatively brief periods following very large magnetic storms the SAA seems to occupy the same position in L-space as in 1970. After the great storm of 24 March 1991 reconfiguration of the inner radiation belt and/or proton injection into the inner belt, a second energetic proton belt was observed to form at approximately equal to 2. As confirmed by a subsequent flight observations, this belt was shown to persist at least for six months. Our measurements also indicate an upward shift in the L location of the primary belt from L = 1.4 to L = 1.5. In addition we confirm through direct real time observations the existence and the approximate magnitude of the East-West effect. If the need exists for improved and updated radiation belt models in the Space Station era, these observations point out the specific features that should be considered and incorporated when this task is undertaken.

  17. Tectono-stratigraphic evolution and crustal architecture of the Orphan Basin during North Atlantic rifting

    Science.gov (United States)

    Gouiza, Mohamed; Hall, Jeremy; Welford, J. Kim

    2016-06-01

    The Orphan Basin is located in the deep offshore of the Newfoundland margin, and it is bounded by the continental shelf to the west, the Grand Banks to the south, and the continental blocks of Orphan Knoll and Flemish Cap to the east. The Orphan Basin formed in Mesozoic time during the opening of the North Atlantic Ocean between eastern Canada and western Iberia-Europe. This work, based on well data and regional seismic reflection profiles across the basin, indicates that the continental crust was affected by several extensional episodes between the Jurassic and the Early Cretaceous, separated by events of uplift and erosion. The preserved tectono-stratigraphic sequences in the basin reveal that deformation initiated in the eastern part of the Orphan Basin in the Jurassic and spread towards the west in the Early Cretaceous, resulting in numerous rift structures filled with a Jurassic-Lower Cretaceous syn-rift succession and overlain by thick Upper Cretaceous to Cenozoic post-rift sediments. The seismic data show an extremely thinned crust (4-16 km thick) underneath the eastern and western parts of the Orphan Basin, forming two sub-basins separated by a wide structural high with a relatively thick crust (17 km thick). Quantifying the crustal architecture in the basin highlights the large discrepancy between brittle extension localized in the upper crust and the overall crustal thinning. This suggests that continental deformation in the Orphan Basin involved, in addition to the documented Jurassic and Early Cretaceous rifting, an earlier brittle rift phase which is unidentifiable in seismic data and a depth-dependent thinning of the crust driven by localized lower crust ductile flow.

  18. American Indian Studies in West Germany.

    Science.gov (United States)

    Bartelt, H. Guillermo

    1986-01-01

    Interest in the American Indian in West Germany is high. Romantic notions, derived from the novels of 19th century German writer Karl May and American westerns shown on German television, combined with a subtle anti-Americanism might be responsible for the American Indian Movement (AIM) support groups that have been forming among students and…

  19. Education and Koranic Literacy in West Africa

    OpenAIRE

    Easton, Peter

    1999-01-01

    The note examines the practical, and literate skills that students acquire at different levels in West African Koranic schools. It is a long-standing parallel system of education, yet, relatively unknown to development planers, thus seldom taken into explicit account in their policies, and strategies. Islamic educational systems have been present since the seventh century, and by the tenth ...

  20. West Point student drops out / Jorgen Johansson

    Index Scriptorium Estoniae

    Johansson, Jorgen

    2001-01-01

    Läti kohus mõistis välja kahjutasu Juris Matusevics'ilt, kes rikkus Läti kaitsejõududega sõlmitud kokkulepet, mis kohustas teda pärast USA West Pointi sõjaväeakadeemia lõpetamist teenima viis aastat Läti armees

  1. Hangzhou:EAST CITY,WEST LAKE

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ View over West Lake,Hangzhou is in Zhejiang Province,eastern coast area of China.It is one of the most important tourism cities here,famous for its natural beauty and historical and cultural heritages,and the political,economic and cultural center of Zhejiang province as well.

  2. West Virginia State Budgeting for Education.

    Science.gov (United States)

    Meckley, Richard

    County school districts in West Virginia are facing a funding crisis. Significant outmigration resulting in decreased school enrollment has caused the state legislature to change the state school aid formula, forcing school districts to lay off large numbers of low-seniority employees. The state legislature's perception that public schools are…

  3. Transcending Communication Barriers with West Africa.

    Science.gov (United States)

    Ampadu, Lena

    Americans doing business with West Africans are limited in their ability to communicate successfully in that part of the world because of language, stereotyping, and ethnocentrism. Americans must become accustomed to British patterns of speech and writing. Stereotypes of Africa, its people, and its cultures perpetuated by the media keep Americans…

  4. Vaccines in Development against West Nile Virus

    Directory of Open Access Journals (Sweden)

    Frederic Tangy

    2013-09-01

    Full Text Available West Nile encephalitis emerged in 1999 in the United States, then rapidly spread through the North American continent causing severe disease in human and horses. Since then, outbreaks appeared in Europe, and in 2012, the United States experienced a new severe outbreak reporting a total of 5,387 cases of West Nile virus (WNV disease in humans, including 243 deaths. So far, no human vaccine is available to control new WNV outbreaks and to avoid worldwide spreading. In this review, we discuss the state-of-the-art of West Nile vaccine development and the potential of a novel safe and effective approach based on recombinant live attenuated measles virus (MV vaccine. MV vaccine is a live attenuated negative-stranded RNA virus proven as one of the safest, most stable and effective human vaccines. We previously described a vector derived from the Schwarz MV vaccine strain that stably expresses antigens from emerging arboviruses, such as dengue, West Nile or chikungunya viruses, and is strongly immunogenic in animal models, even in the presence of MV pre-existing immunity. A single administration of a recombinant MV vaccine expressing the secreted form of WNV envelope glycoprotein elicited protective immunity in mice and non-human primates as early as two weeks after immunization, indicating its potential as a human vaccine.

  5. Writing the New West: A Critical Review

    Science.gov (United States)

    Robbins, Paul; Meehan, Katharine; Gosnell, Hannah; Gilbertz, Susan J.

    2009-01-01

    A vast and growing interdisciplinary research effort has focused on the rise of the so-called New West, purportedly the product of regional socioeconomic, political, and ecological upheavals in states like Montana and Colorado. Reviewing the growing research on this problem in sociology, economics, geography, and conservation science, this article…

  6. West Indian Sojourners in Guatemala and Honduras

    Directory of Open Access Journals (Sweden)

    Ronald N. Harpelle

    2012-12-01

    Full Text Available Review of: Race, Nation, and West Indian Immigration to Honduras, 1890-1940. Glenn A. Chambers. Baton Rouge: Louisiana State University Press, 2010. xii +202 pp. (Cloth US$ 35.00Black Labor Migration in Caribbean Guatemala, 1882-1923. Frederick Douglass Opie. Gainesville: University Press of Florida, 2009. 145 pp. (Cloth US$ 65.00

  7. Design and manufacturing of WEST Baffle

    Energy Technology Data Exchange (ETDEWEB)

    Batal, Tristan, E-mail: tristan.batal@cea.fr [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Firdaouss, Mehdi; Richou, Marianne; Ferlay, Fabien; Larroque, Sébastien; Gargiulo, Laurent [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Dupas, Timothée [SODITECH Ingénierie SA, 1 bis allée des gabians, 06150 Cannes la Bocca (France); Verger, Jean-Marc; Doceul, Louis; Samaille, Franck; Bucalossi, Jérôme [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Salami, Michael [AVANTIS groupe, 12 route de Saint Mathieu, 06130 Grasse (France)

    2015-10-15

    Highlights: • Disruption's torque in the PFC was simulated thanks to ANSYS. • The ANSYS thermal results comply with WEST project requirements. • The cycling analysis complies with WEST project requirements. • 316L components comply with A level RCC-MRx criteria. - Abstract: The Tore Supra tokamak is being transformed in an X-point divertor fusion device in the frame of the WEST project, launched in support to the Iter tungsten divertor strategy. The WEST Baffle aims to evacuate particles by creating a toroidal pumping throat. It also protects the lower divertor cooling pipes and the passive stabilization plate from heat fluxes. The Baffle is made of actively cooled plasma facing components (PFCs), with underneath a passive stabilization plate and a support beam. The Baffle design is presented in a first part. In a second time the different ANSYS simulations are described: electromagnetic, thermal and mechanical results are presented. The design choices are justified for the different results obtained thanks to the simulation. In a final part, some aspects of the PFC manufacturing are presented.

  8. Epidemiology: Malaria in a warmer West Africa

    Science.gov (United States)

    Caminade, C.; Jones, A. E.

    2016-11-01

    Malaria risk in West Africa is expected to fall (western region) or remain the same (eastern region) in response to climate change over the twenty-first century. This is primarily due to extreme temperature conditions projected under a high greenhouse gas emissions scenario.

  9. 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 kimbe...... into the reworked Archean North of the Naqssugtoqidian deformation front....

  10. Why We Need West Nile Virus Testing

    Centers for Disease Control (CDC) Podcasts

    2016-09-27

    Dr. Rodrigo Hasbun, a professor of infectious diseases at McGovern Medical School at UT Health, discusses the need for West Nile virus testing in Texas.  Created: 9/27/2016 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 9/27/2016.

  11. 76 FR 37996 - West Virginia Regulatory Program

    Science.gov (United States)

    2011-06-29

    ... surface coal mining and reclamation operations on non- Federal and non-Indian lands within its borders by... of approval of the West Virginia program in the January 21, 1981, Federal Register (46 FR 5915). You... actual language of State regulatory programs and program amendments because each program is drafted...

  12. West Florida shelf upwelling: Origins and pathways

    Science.gov (United States)

    Weisberg, Robert H.; Zheng, Lianyuan; Liu, Yonggang

    2016-08-01

    Often described as oligotrophic, the west Florida continental shelf supports abundant fisheries, experiences blooms of the harmful alga, Karenia brevis, and exhibits subsurface chlorophyll maxima evident in shipboard and glider surveys. Renewal of inorganic nutrients by the upwelling of deeper ocean water onto the shelf may account for this, but what are the origins and pathways by which such new water may broach the shelf break and advance toward the shoreline? We address these questions via numerical model simulations of pseudo-Lagrangian, isopycnic water parcel trajectories. Focus is on 2010, when the west Florida shelf was subjected to an anomalously protracted period of upwelling caused by Gulf of Mexico Loop Current interactions with the shelf slope. Origins and pathways are determined by integrating trajectories over successive 45 day intervals, beginning from different locations along the shelf break and at various locations and depths along the shelf slope. Waters upwelling across the shelf break are found to originate from relatively shallow depths along the shelf slope. Even for the anomalous 2010 year, much of this upwelling occurs from about 150 m and above, although waters may broach the shelf break from 300 m depth, particularly in the Florida Panhandle. Such interannual renewal of west Florida shelf waters appears to have profound effects on west Florida shelf ecology.

  13. Large Acrobatic Play Pilgrimage to the West

    Institute of Scientific and Technical Information of China (English)

    马洁

    2006-01-01

    Hosted by Ministry of Culture and Guangzhou Municipal People's Government,Guangzhou Bureau of Culture organized a list of first-class singing and dancing and acrobatic plays in Guangzhou in September 2006. Among these plays, large original acrobatic play Pilgrimage to the West of Guangzhou Acrobatic Troupe went on the stage during October 12th and November 5th.

  14. 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...

  15. Mastomys natalensis and Lassa fever, West Africa.

    Science.gov (United States)

    Lecompte, Emilie; Fichet-Calvet, Elisabeth; Daffis, Stéphane; Koulémou, Kékoura; Sylla, Oumar; Kourouma, Fodé; Doré, Amadou; Soropogui, Barré; Aniskin, Vladimir; Allali, Bernard; Kouassi Kan, Stéphane; Lalis, Aude; Koivogui, Lamine; Günther, Stephan; Denys, Christiane; ter Meulen, Jan

    2006-12-01

    PCR screening of 1,482 murid rodents from 13 genera caught in 18 different localities of Guinea, West Africa, showed Lassa virus infection only in molecularly typed Mastomys natalensis. Distribution of this rodent and relative abundance compared with M. erythroleucus correlates geographically with Lassa virus seroprevalence in humans.

  16. Coeliac disease in children of West Indian origin.

    OpenAIRE

    Hung, J C; Phillips, A D; Walker-Smith, J A

    1995-01-01

    Coeliac disease is uncommon in populations of non-European origin. Two English born West Indian children with coeliac disease are presented. The diagnosis should be considered in children of West Indian origin with chronic diarrhoea.

  17. Characteristics of waves off Goa, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    SanilKumar, V.; AshokKumar, K.; Anand, N.M.

    Directional wave measurements were carried out using Datawell directional waverider buoy off Goa along west coast of India during the south west monsoon period in 1996 and the results are presented. Theoretical joint distribution of wave height...

  18. West Coast DA Event data - West Coast Toxic Pseudo-nitzschia bloom

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Beginning in the spring of 2015 the US West Coast began to experience the most wide-spread toxic Pseudo-nitzschia bloom to date, after approximately eight years...

  19. 78 FR 59841 - Approval and Promulgation of Air Quality Implementation Plans; West Virginia; West Virginia's...

    Science.gov (United States)

    2013-09-30

    ..., disproportionate human health or environmental effects, using practicable and legally permissible methods, under... Environmental protection, Air pollution control, Incorporation by reference, Nitrogen dioxide, Particulate... Environmental Protection, Division of Air Quality, 601 57th Street SE., Charleston, West Virginia 25304....

  20. 77 FR 10423 - Approval and Promulgation of Air Quality Implementation Plans; West Virginia; Amendments to West...

    Science.gov (United States)

    2012-02-22

    ... address, as appropriate, disproportionate human health or environmental effects, using practicable and... preempt tribal law. List of Subjects in 40 CFR Part 52 Environmental protection, Air pollution control...; Amendments to West Virginia's Ambient Air Quality Standards AGENCY: Environmental Protection Agency...

  1. Optimal for difficult roofs. East-west orientation; Optimal fuer schwierige Daecher. Ost-West-Ausrichtung

    Energy Technology Data Exchange (ETDEWEB)

    Bouattour, Mohamed Ali [Solar Frontier Europe GmbH, Muenchen (Germany)

    2013-10-01

    With the help of CIS solar modules the unfavorable east-west roofs can be also use efficiently and profitably, since the good weak-light performance almost compensates the weak light components characterized irradiation conditions. [German] Mit Hilfe der CIS-Solarmodule lassen sich auch die unguenstige Ost-West-Daecher effizient und profitabel nutzen, da das gute Schwachlichtverhalten die hier von schwachen Lichtanteilen gepraegten Einstrahlungsverhaeltnisse nahezu kompensiert.

  2. West Virginia Interpretive Guide Training: A Collaborative Effort

    Science.gov (United States)

    Balcarczyk, Kelly; McKenney, Kathryn; Smaldone, Dave; Arborgast, Doug

    2013-01-01

    West Virginia University's Extension Service partnered with the Recreation, Parks, and Tourism Resources Program to improve guide performance in West Virginia's tourism industry. The result of this partnership is a West Virginia Interpretive Guide Training program aimed at providing low-cost, widely available training to guides…

  3. 78 FR 51199 - West Virginia; Major Disaster and Related Determinations

    Science.gov (United States)

    2013-08-20

    ... SECURITY Federal Emergency Management Agency West Virginia; Major Disaster and Related Determinations... Presidential declaration of a major disaster for the State of West Virginia (FEMA-4132-DR), dated July 26, 2013...''), as follows: I have determined that the damage in certain areas of the State of West...

  4. 75 FR 18517 - West Virginia; Major Disaster and Related Determinations

    Science.gov (United States)

    2010-04-12

    ... SECURITY Federal Emergency Management Agency West Virginia; Major Disaster and Related Determinations... Presidential declaration of a major disaster for the State of West Virginia (FEMA-1893-DR), dated March 29... Act''), as follows: I have determined that the damage in certain areas of the State of West...

  5. 75 FR 25873 - West Virginia; Major Disaster and Related Determinations

    Science.gov (United States)

    2010-05-10

    ... SECURITY Federal Emergency Management Agency West Virginia; Major Disaster and Related Determinations... Presidential declaration of a major disaster for the State of West Virginia (FEMA-1903-DR), dated April 23... Act''), as follows: I have determined that the damage in certain areas of the State of West...

  6. 75 FR 39560 - West Virginia; Major Disaster and Related Determinations

    Science.gov (United States)

    2010-07-09

    ... SECURITY Federal Emergency Management Agency West Virginia; Major Disaster and Related Determinations... Presidential declaration of a major disaster for the State of West Virginia (FEMA-1918-DR), dated June 24, 2010... follows: I have determined that the damage in certain areas of the State of West Virginia resulting...

  7. 77 FR 46103 - West Virginia; Major Disaster and Related Determinations

    Science.gov (United States)

    2012-08-02

    ... SECURITY Federal Emergency Management Agency West Virginia; Major Disaster and Related Determinations... Presidential declaration of a major disaster for the State of West Virginia (FEMA-4071-DR), dated July 23, 2012...''), as follows: I have determined that the damage in certain areas of the State of West...

  8. 77 FR 76061 - West Virginia; Major Disaster and Related Determinations

    Science.gov (United States)

    2012-12-26

    ... SECURITY Federal Emergency Management Agency West Virginia; Major Disaster and Related Determinations... Presidential declaration of a major disaster for the State of West Virginia (FEMA-4093-DR), dated November 27... West Virginia resulting from Hurricane Sandy during the period of October 29 to November 8, 2012, is...

  9. 75 FR 11902 - West Virginia; Major Disaster and Related Determinations

    Science.gov (United States)

    2010-03-12

    ... SECURITY Federal Emergency Management Agency West Virginia; Major Disaster and Related Determinations... Presidential declaration of a major disaster for the State of West Virginia (FEMA-1881-DR), dated March 2, 2010... follows: I have determined that the damage in certain areas of the State of West Virginia resulting from...

  10. Excerpt from East Is West and West Is East: Gender, Culture, and Interwar Encounters between Asia and America

    OpenAIRE

    Kuo, Karen

    2013-01-01

    Excerpted from Karen Kuo, East Is West and West Is East: Gender, Culture, and Interwar Encounters between Asia and America (Philadelphia: Temple University Press, 2012). Reprinted with permission from Temple University Press.

  11. Excerpt from East Is West and West Is East: Gender, Culture, and Interwar Encounters between Asia and America

    Directory of Open Access Journals (Sweden)

    Karen Kuo

    2013-09-01

    Full Text Available Excerpted from Karen Kuo, East Is West and West Is East: Gender, Culture, and Interwar Encounters between Asia and America (Philadelphia: Temple University Press, 2012.Reprinted with permission from Temple University Press.

  12. Role of the Convective Scheme in Modeling Initiation and Intensification of Tropical Depressions over the North Atlantic

    Science.gov (United States)

    Duvel, Jean Philippe; Camargo, Suzana; Sobel, Adam

    2016-04-01

    Modifications of the large-scale environment related to intraseasonal (MJO) and interannual (ENSO) time-scale variability or to global climate warming may have important impacts on the tropical cyclonic activity. This sensitivity of tropical cyclones (TC) on environmental changes can now be studied using General Circulation Models (GCM). Before doing sensitivity studies with a GCM, it is interesting to assess the representation of the TC activity for different configurations (resolution, parameterization) of the GCM in present climate conditions and to trace possible causes of bias in TC number, location or strength. A possible approach to do this assessment is to separate initiation and intensification processes. By using either GCM output, or meteorological analysis combined to TC observation databases, it is possible to study the condition of formation of tropical depressions vortices (TDV) at an early stage and their possible intensification into a TC (say the Tropical Storm stage). We use the LMDZ GCM to study the sensitivity of TDV characteristics to different entrainment and closure formulations of the convective scheme. The study focuses on the Tropical North Atlantic using the "zoom" capability of the LMDZ GCM. The horizontal resolution of the model is set to 0.75° over a large region of the North Atlantic and West Africa. The GCM is free to run in this region and is tied to ERA-Interim reanalysis outside that region, with intermediate relaxation times in-between. We use the Tiedtke convective scheme with entrainment and closure based on the moisture convergence, or with an entrainment based on the relative humidity of the environment, and additionally a closure based on CAPE. Each configuration is run for 10 years between 2000 and 2009 with prescribed SST. In summary, the convective entrainment based on the relative humidity in the environment deepens the TDV in LMDZ, resulting in more TDV and TC. The convective closure mitigates this tendency and

  13. Combating Narco-Terrorism in West Africa

    Science.gov (United States)

    2012-06-15

    n Maritime ~c<.:urity improvements hoth on the American side of the Atlantic and along European coa’lta l water ~ have deterred trafficker~ from...Working with African nations on transnational i ssue ~ ~uch a!> drug smuggling , money I au ntlcri ng, iII icit <Hill’-. and trafficking in person...maritime ’>alcty :111d ’l’l’lll’il) along ih territorial and <.:P:hlal water -.. It j-, a ol African na\\ ie:-.. eoa’t guanb ami mariner .... 1\\PS g11al i

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

    DEFF Research Database (Denmark)

    Malanski, Evandro

    feeding on prey sizes of about 5% of their own size (Paper I) and consequently the prey preference spectra covered calanoid nauplii, cladocerans and calanoid copepodites with increasing larval size. In the Godthåbsfjord system and Fyllas Bank area, 4 hydrographic zones were defined; in each zone distinct...... is linked to the break-up of ice cover and the subsequent irradiance increase in the water column, climatic changes in Arctic regions could lead to a mismatch between larval emergence and optimal conditions for their feeding and growth. Thus it would be feasible to investigate the capelin stock genetic...

  15. A new climate index controlling winter wave activity along the Atlantic coast of Europe: The West Europe Pressure Anomaly

    Science.gov (United States)

    Castelle, Bruno; Dodet, Guillaume; Masselink, Gerd; Scott, Tim

    2017-02-01

    A pioneering and replicable method based on a 66-year numerical weather and wave hindcast is developed to optimize a climate index based on the sea level pressure (SLP) that best explains winter wave height variability along the coast of western Europe, from Portugal to UK (36-52°N). The resulting so-called Western Europe Pressure Anomaly (WEPA) is based on the sea level pressure gradient between the stations Valentia (Ireland) and Santa Cruz de Tenerife (Canary Islands). The WEPA positive phase reflects an intensified and southward shifted SLP difference between the Icelandic low and the Azores high, driving severe storms that funnel high-energy waves toward western Europe southward of 52°N. WEPA outscores by 25-150% the other leading atmospheric modes in explaining winter-averaged significant wave height, and even by a largest amount the winter-averaged extreme wave heights. WEPA is also the only index capturing the 2013/2014 extreme winter that caused widespread coastal erosion and flooding in western Europe.

  16. 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

    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...... where other data (such as egg surveys) are drawn in to compensate for the spatial issues could prove to be the way forward. Crown Copyright (C) 2015 Published by Elsevier Ltd....

  17. 77 FR 74119 - Snapper-Grouper Fishery of the South Atlantic; 2012 Commercial Accountability Measure and Closure...

    Science.gov (United States)

    2012-12-13

    ... the South Atlantic; 2012 Commercial Accountability Measure and Closure for South Atlantic Snowy... (NOAA), Commerce. ACTION: Temporary rule; closure. SUMMARY: NMFS implements accountability measures...

  18. 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.

  19. Abundance and distribution of major groups of diazotrophic cyanobacteria and their potential contribution to N₂ fixation in the tropical Atlantic Ocean.

    Science.gov (United States)

    Goebel, Nicole L; Turk, Kendra A; Achilles, Katherine M; Paerl, Ryan; Hewson, Ian; Morrison, Amanda E; Montoya, Joseph P; Edwards, Christopher A; Zehr, Jonathan P

    2010-12-01

    The abundances of six N₂-fixing cyanobacterial phylotypes were profiled at 22 stations across the tropical Atlantic Ocean during June 2006, and used to model the contribution of the diazotrophs to N₂ fixation. Diazotroph abundances were measured by targeting the nifH gene of Trichodesmium, unicellular groups A, B, C (UCYN-A, UCYN-B and UCYN-C), and diatom-cyanobiont symbioses Hemiaulus-Richelia, Rhizosolenia-Richelia and Chaetoceros-Calothrix. West to east gradients in temperature, salinity and nutrients [NO₃⁻ + NO₂⁻, PO₄³⁻, Si(OH)₄] showed the influence of the Amazon River plume and its effect on the distributions of the diazotrophs. Trichodesmium accounted for more than 93% of all nifH genes detected, dominated the warmer waters of the western Atlantic, and was the only diazotroph detected at the equatorial upwelling station. UCYN-A was the next most abundant (> 5% of all nifH genes) and dominated the cooler waters of the eastern Atlantic near the Cape Verde Islands. UCYN-C was found at a single depth (200 m) of high salinity and low temperature and nutrients, whereas UCYN-B cells were widespread but in very low abundance (6.1 × 10¹ ± 4.6 × 10² gene copies l⁻¹). The diatom-cyanobionts were observed primarily in the western Atlantic within or near the high Si(OH)₄ input of the Amazon River plume. Overall, highest diazotroph abundances were observed at the surface and declined with depth, except for some subsurface peaks in Trichodesmium, UCYN-B and UCYN-A. Modelled contributions of Trichodesmium, UCYN-B and UCYN-A to total N₂ fixation suggested that Trichodesmium had the largest input, except for the potential of UCYN-A at the Cape Verde Islands.

  20. A Multivariate Analysis of Freshwater Variability over West Africa

    Science.gov (United States)

    Andam-Akorful, S. A.; He, X.; Ferreira, V. G.; Quaye-Ballard, J. A.

    2015-12-01

    As one of the most vulnerable regions to climate change, West Africa (WA) has since the 1970s suffered sustained reduction in rainfall amounts, leading to droughts and associated negative impacts on its water resources. Although rainfall rates have been reported to have experienced a degree of recovery, dry conditions persist. Additionally, the region faces perennial flooding, thus resulting in a highly variable hydrologic regime due to the extreme climate conditions. This therefore necessitates routine monitoring of the WA's freshwater reserves and its response to climate variations at the short and long term scales to aid sustainable use and management. However, this monitoring is hampered by data deficiency issues within the region. Consequently, dynamics leading to changes in water availability over the region are not completely understood. In this work, the recent flux and state of freshwater availability over WA from 1979 to 2013 is assessed by investigating the coupled variability of GRACE-derived terrestrial water storage (TWS) and its changes (TWSC) estimates with rainfall, evapotranspiration, and land surface air temperature (LSAT), as well as, major global and regional teleconnection indices using complex principal component analysis and wavelet transforms. Since GRACE covers a relatively short period, and thereby present challenges for long to medium term analyses, Artificial Neural Network (ANN) is employed to extend the GRACE series to 1979. The results from the ANN proved to be robust upon evaluation; spatially-averaged series for major basins and sub-climatic zones, as well as, the whole of WA presented RMSE, Nash-Sutcliffe efficient, and coefficient of determination (R2) of 11.83 mm, 0.76 and 0.89 respectively. Overall, the results obtained from this study indicate that, sustained increase in water flux, in terms of TWSC, contributed to a resurgence in freshwater reserves in the 21st century over WA from the low levels in the late 20th century

  1. Issues of Sustainability of Coastal Groundwater Resources: Benin, West Africa

    Directory of Open Access Journals (Sweden)

    Andrew D. Mullen

    2010-08-01

    Full Text Available The largest city in Benin, West Africa (Cotonou, is reliant upon groundwater for its public water supply. This groundwater is derived from the Godomey well field which is located approximately 5 Km north of the coast of the Atlantic Ocean and in close proximity to Lake Nokoue—a shallow lake containing water with elevated concentration of chloride and other elements. Historical data indicate increased chloride concentration in a number of wells nearest to the lake, with unknown contribution from groundwater encroachment from the coastal area. Hence, there is substantial interest in better characterizing this groundwater system for the purpose of determining appropriate management practices and degree of sustainability. Among the efforts attempted to date are a series of numerical models ranging from assessment of flow to a recent effort to include density-dependent transport from the lake. In addition, substantial field characterization has been pursued including assessment of shallow water chemistry along the region of the coastal lagoon and border of the lake, characterization of hydraulic response to pumpage in the aquifer system, estimation of the distribution of electrical resistivity with depth along the coastal lagoons, and installation of multi-level piezometers at seven locations in the lake. When integrated across methods, these numerical and field results indicate that the lake remains a primary concern in terms of a source of salinity in the aquifer. Further, the coastal region appears to be more complex than previously suggested and may represent a future source of salt-water encroachment as suggested by current presence of saline waters at relatively shallow depths along the coast. Finally, hydraulic testing suggests that both natural and pumping-based fluctuations in water levels are present in this system. Substantial additional characterization and modeling efforts may provide a significantly greater understanding of the

  2. Effects of highway construction on stream water quality and macroinvertebrate condition in a Mid-Atlantic Highlands watershed, USA

    Science.gov (United States)

    Chen, Y.; Viadero, R.C.; Wei, X.; Fortney, Ronald H.; Hedrick, Lara B.; Welsh, S.A.; Anderson, James T.; Lin, L.-S.

    2009-01-01

    Refining best management practices (BMPs) for future highway construction depends on a comprehensive understanding of environmental impacts from current construction methods. Based on a before-after-control impact (BACI) experimental design, long-term stream monitoring (1997-2006) was conducted at upstream (as control, n = 3) and downstream (as impact, n = 6) sites in the Lost River watershed of the Mid-Atlantic Highlands region, West Virginia. Monitoring data were analyzed to assess impacts of during and after highway construction on 15 water quality parameters and macroinvertebrate condition using the West Virginia stream condition index (WVSCI). Principal components analysis (PCA) identified regional primary water quality variances, and paired t tests and time series analysis detected seven highway construction-impacted water quality parameters which were mainly associated with the second principal component. In particular, impacts on turbidity, total suspended solids, and total iron during construction, impacts on chloride and sulfate during and after construction, and impacts on acidity and nitrate after construction were observed at the downstream sites. The construction had statistically significant impacts on macroinvertebrate index scores (i.e., WVSCI) after construction, but did not change the overall good biological condition. Implementing BMPs that address those construction-impacted water quality parameters can be an effective mitigation strategy for future highway construction in this highlands region. Copyright ?? 2009 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

  3. Extension and inversion structures in the Tethys-Atlantic linkage zone, Algarve Basin, Portugal

    Science.gov (United States)

    Ramos, Adrià; Fernández, Oscar; Terrinha, Pedro; Muñoz, Josep Anton

    2016-07-01

    The Algarve Basin is a Meso-Cenozoic sedimentary basin overlying Carboniferous basement, located in the southwestern margin of the Iberian Peninsula. Its structure reveals a protracted tectonic history comprising various pulses of Mesozoic extension followed by Cenozoic compression. This work deals with the structure along the northern margin, where the Mesozoic extensional structures and Cenozoic inversion structures crop out. The strike of the extensional structures ranges from E-W to N-S, as controlled by a shift from Tethyan-dominated extension in the east to Atlantic-dominated extension in the west. Contractional structures are inverted extensional structures, following their same trends. It is argued that the thickness of the Hettangian evaporite layer exerts a strong control on the structural style throughout the basin during the extensional and inversion episodes. The basin is affected by thick-skinned deformation along the northern margin, where salt is thin or absent, basement involved fault systems and short-cut structures. Basinward, as the Hettangian salt thickens, the margin is affected by thin-skinned deformation, with listric and down-to-the-basin growth faults, diapirism and salt-cored detachment folds. The aim was to discuss the key tectonic features, the relevance of salt, and understand the nature, timing, and significance of all these structures in the regional tectonic evolution.

  4. RETHINKING THE BLACK SEA: BETWEEN THE TRANS-ATLANTIC AND THE EURASIAN PROJECTS

    Directory of Open Access Journals (Sweden)

    Şerban Filip Cioculescu

    2013-06-01

    Full Text Available The Black Sea region as a buffer between great powers and cordon sanitaire was and still is important in European history. After the 18th century, the Russian empire began a gradual but unstoppable move towards the conquest of the region, leading to a setback for Turkish influence. The Crimean War enabled Western powers to contain Russian expansion for some decades. For small and medium-sized countries like Romania, it is difficult to erase historic experiences from their collective memory. During the Cold War, the Black Sea was a virtual “Soviet lake” from a military point of view. The West controlled only the straits “owned” by Turkey following the Montreux Convention. After the implosion of the USSR, this strategic area was neglected by the Western powers and viewed by the Russian Federation as a traditional sphere of influence. Since 1991, Ukraine holds about 30% of the northern shore of the Black Sea, Georgia controls roughly 12% of the maritime littoral (including the separatist territories while Russia owns about 13% of the Black Sea shores. Turkey and Ukraine hold the biggest share of the Black Sea shore. Generally speaking, during the two last decades, there have been two competing visions about the future: the Euro-Atlantic one, which insists on opening and internationalising the sea, and the Eurasian vision, which wants the Black Sea to remain closed and impenetrable to foreign interferences. This article deals with these issues.doi: 10.5787/41-1-1051

  5. Zschokkella hildae Auerbach, 1910: phylogenetic position, morphology, and location in cultured Atlantic cod.

    Science.gov (United States)

    Holzer, Astrid Sibylle; Wootten, Rod; Sommerville, Christina

    2010-06-01

    The myxozoan Zschokkella hildae Auerbach, 1910, was detected with a prevalence of 100% in cultured Atlantic cod, Gadus morhua L. aged 1+ from a culture facility on the west coast of Scotland. Sporogonic stages of Z. hildae, plasmodia producing 2-5 mature spores, were located predominantly in the collecting ducts and ureters of the kidney, and spores were present in the urine collected from the bladder. Less frequently, plasmodia were detected in the interstitial tissue of the kidney. The parasite prevalence in cultured fish was considerably higher than reported in wild fish but no obvious signs of pathology were detected. SSU rDNA sequencing and phylogenetic analysis showed that Z. hildae is closely related to a Sinuolinea sp. from the urinary system of turbot, Psetta maxima (L.), and that these two species, together with other myxozoans from the urinary system of marine fish cluster together in a sub-clade of the recognised marine clade of myxozoans. This sub-clade is characterised by a specific linear expansion segment, helix E23_15 in the secondary structure of variable region V4 of the SSU rDNA. Z. hildae and Sinuolinea sp. show extraordinary large linear expansion segment in both V4 and V7 and an important number of complementary base changes in the conservative regions of the SSU rDNA, indicating considerable evolutionary changes in the SSU rDNA of these species when compared with other myxozoans from the marine environment.

  6. 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.

  7. Instrumental evidence of an unusually strong West African Monsoon in the 19th century

    Science.gov (United States)

    Gallego, David; Ordoñez, Paulina; Ribera, Pedro; Peña-Ortiz, Cristina; Garcia-Herrera, Ricardo; Vega, Inmaculada; Gomez, Francisco de Paula

    2016-04-01

    The precipitation in the Sahel -which is mainly controlled by the dynamics of the West African Monsoon-, has been in the spot of the climate community for the last three decades due to the persistence of the drought period that started in the 1970s. Unfortunately, reliable meteorological series in this area are only available since the beginning of the 20th Century, thus limiting our understanding of the significance of this period from a long term perspective. Currently, our knowledge of what happened in times previous to the 20th Century essentially relies in documentary or proxy sources. In this work, we present the first instrumental evidence of a 50 year-long period characterised by an unusually strong West African monsoon in the19th Century. Following the recent advances in the generation of climatic indices based on data from ship's logbooks, we used historical wind observations to compute a new index (the so-called ASWI) for characterising the strength of the West African Monsoon. The ASWI is based in the persistence of the southwesterly winds in the [29°W-17°W;7°N-13°N] area and it has been possible to compute it since 1790 for July and since 1839 for August and September. We show that the ASWI is a reliable measure of the monsoon's strength and the Sahelian rainfall. Our new series clearly shows the well-known drought period starting in the 1970s. During this dry period, the West African Monsoon was particularly weak and interestingly, we found that since then, the correlations with different climatic patterns such as the Pacific and Atlantic "El Niño" changed significantly in relation to those of the previous century. Remarkably, our results also show that the period 1839-1890 was characterised by an unusually strong and persistent monsoon. Notwithstanding, two of the few dry years within this period were concurrent with large volcanic eruptions in the Northern Hemisphere. This latter result supports the recently suggested relationship between major

  8. West Africa land use and land cover time series

    Science.gov (United States)

    Cotillon, Suzanne E.

    2017-02-16

    Started in 1999, the West Africa Land Use Dynamics project represents an effort to map land use and land cover, characterize the trends in time and space, and understand their effects on the environment across West Africa. The outcome of the West Africa Land Use Dynamics project is the production of a three-time period (1975, 2000, and 2013) land use and land cover dataset for the Sub-Saharan region of West Africa, including the Cabo Verde archipelago. The West Africa Land Use Land Cover Time Series dataset offers a unique basis for characterizing and analyzing land changes across the region, systematically and at an unprecedented level of detail.

  9. The Influence of the West in American Civil War

    Institute of Scientific and Technical Information of China (English)

    张铂

    2016-01-01

    After the 19th century, the West was no longer an appendage of the South and the North. During the Civil War, the North had superiority in both economy and politics. This owed much to the West. The share of the same labour system laid the foundation of the union between the North and the West. The victory of the North linked closely to the support of the West. The essay analyzed the contribution made by the West from the perspectives of economy and politics.

  10. 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.)

  11. Rare earth elements (REEs) in the tropical South Atlantic and quantitative deconvolution of their non-conservative behavior

    Science.gov (United States)

    Zheng, Xin-Yuan; Plancherel, Yves; Saito, Mak A.; Scott, Peter M.; Henderson, Gideon M.

    2016-03-01

    This study presents new concentration measurements of dissolved rare earth elements (dREEs) along a full-depth east-west section across the tropical South Atlantic (∼12°S), and uses these data to investigate the oceanic cycling of the REEs. Enrichment of dREEs, associated with the redox cycling of Fe-Mn oxides, is observed in the oxygen minimum zone (OMZ) off the African shelf. For deeper-waters, a multi-parameter mixing model was developed to deconvolve the relative importance of physical transport (i.e., water mass mixing) from biogeochemical controls on the dREE distribution in the deep Atlantic. This approach enables chemical processes involved in REE cycling, not apparent from the measurements alone, to be distinguished and quantified. Results show that the measured dREE concentrations below ∼1000 m are dominantly controlled (>75%) by preformed REE concentrations resulting from water mass mixing. This result indicates that the linear correlation between dREEs and dissolved Si observed in Atlantic deep waters results from the dominantly conservative behavior of these tracers, rather than from similar chemical processes influencing both dREEs and Si. Minor addition of dREEs (∼10% of dNd and ∼5% of dYb) is observed in the deep (>∼4000 m) Brazil Basin, resulting from either remineralization of particles in-situ or along the flow path. Greater addition of dREEs (up to 25% for dNd and 20% for dYb) is found at ∼1500 m and below ∼4000 m in the Angola Basin near the African continental margin. Cerium anomalies suggest that different sources are responsible for these dREE addition plumes. The 1500 m excess is most likely attributed to dREE release from Fe oxides, whereas the 4000 m excess may be due to remineralization of calcite. Higher particulate fluxes and a more sluggish ocean circulation in the Angola Basin may explain why the dREE excesses in this basin are significantly higher than that observed in the Brazil Basin. Hydrothermal venting over the

  12. 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

  13. 77 FR 70149 - Mid-Atlantic Fishery Management Council (MAFMC); Public Meetings

    Science.gov (United States)

    2012-11-23

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

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

    Data.gov (United States)

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

  15. 76 FR 31941 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; Horseshoe Crabs; Application...

    Science.gov (United States)

    2011-06-02

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

  16. 75 FR 31421 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; Application for Exempted...

    Science.gov (United States)

    2010-06-03

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

  17. 78 FR 29331 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; Horseshoe Crabs; Application...

    Science.gov (United States)

    2013-05-20

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

  18. 77 FR 55457 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; Horseshoe Crabs; Application...

    Science.gov (United States)

    2012-09-10

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

  19. 75 FR 34092 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; Weakfish Fishery

    Science.gov (United States)

    2010-06-16

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

  20. 77 FR 38775 - Schedules for Atlantic Shark Identification Workshops and Protected Species Safe Handling...

    Science.gov (United States)

    2012-06-29

    ... National Oceanic and Atmospheric Administration RIN 0648-XC042 Schedules for Atlantic Shark Identification... Shark Identification workshop originally scheduled for August 9, 2012, in Rosenberg, TX, has been... 77471. The July and September workshop dates remain unchanged. Atlantic Shark Identification...

  1. EU habitats of interest: an insight into Atlantic and Mediterranean beach and foredunes

    NARCIS (Netherlands)

    Feola, S.; Carranza, M.L.; Schaminee, J.H.J.; Acosta, A.T.R.; Janssen, J.A.M.

    2011-01-01

    Abstract We compared the Atlantic and Mediterranean beach and foredune habitats of European interest, focusing on floristic, structural and ecological features. We selected two representative sites of Atlantic (The Netherlands) and Mediterranean (Italy) coastal dunes. From a georeferenced vegetation

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

    Data.gov (United States)

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

  3. 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.

  4. 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.

  5. Tectonics in the Northwestern West Philippine Basin

    Institute of Scientific and Technical Information of China (English)

    Ni Xianglong; Wu Shiguo; Shinjo Ryuichi

    2008-01-01

    The West Philippine basin (WPB) is a currently inactive marginal basin belonging to Philippine Sea plate, which has a complex formation history and various crust structures. Based on gravity, magnetic and seismic data, the tectonics in West Philippine basin is characterized by amagnma spreading stage and strike slip fractures. NNE trending Okinawa-Luzon fracture zone is a large fracture zone with apparent geomorphology and shows a right-handed movement. The results of joint gravity-magnetic-seismic inversion suggest that the Okinawa-Luzon fracture zone has intensive deformation and is a transform fault. Western existence of the NW trending fractures under Ryukyu Islands Arc is the main cause of the differences between south and north Okinawa Trough. The Urdaneta plateau is not a remained arc, but remnant of mantle plume although its lava chemistry is similar to oceanic island basalt (OIB).

  6. Aerial view of the West Area complex

    CERN Multimedia

    1976-01-01

    The SPS lies below ground beyond the top of the picture, and the proton beam from it enters the large West Hall from the right. All hadronic beams but one were concentrated in this hall. The neutrino beam from the underground target Passes through BEBC in the tall structure left of centre. The light-coloured building further left houses the neutrino counter experiments WA1 and WA18, and at the left end of the line, in the small block near the edge of the picture sits Gargamelle on a pedestal, since the beam is rising at an angle of about 2 deg. From right to left: West Hall - Bld 180; BEBC - Bld 191; Neutrino - Bld 182; Gargamelle - Bld 185.

  7. Multiculturalism and Minority Rights: West and East

    Directory of Open Access Journals (Sweden)

    Will Kymlicka

    2002-10-01

    Full Text Available Are Western models of multiculturalism and minority rights relevant for the post-Communist countries of Central and Eastern Europe? This article describes a range of Western models, and explores the social and political conditions that have led to their adoption in the West. It then considers various factors which might make the adoption of these models difficult in Eastern Europe, and considers the potential role of the international community in overcoming these obstacles.

  8. Developing Pipeline Transportation in West China

    Institute of Scientific and Technical Information of China (English)

    Yang Chenghan; Wang Wei

    1997-01-01

    @@ Since the late 1980s, focus of exploration and development for oil & gas has been diverted to thewest of China, resulting in the discovery and development of Shaanbei gas field followed by large-scale exploration and development of Tarim,Turpan and Hami basins. Responding to this situation, pipeline construction focus has also been transferred to west China where large-scale development of pipeline transportation, an opportunity as well as a challenge, is expected.

  9. WEST COAST REGIONAL CARBON SEQUESTRATION PARTNERSHIP

    Energy Technology Data Exchange (ETDEWEB)

    Larry Myer; Terry Surles; Kelly Birkinshaw

    2004-01-01

    The West Coast Regional Carbon Sequestration Partnership is one of seven partnerships which have been established by the US Department of Energy (DOE) to evaluate carbon dioxide capture, transport and sequestration (CT&S) technologies best suited for different regions of the country. The West Coast Region comprises Arizona, California, Nevada, Oregon, Washington, and the North Slope of Alaska. Led by the California Energy Commission, the West Coast Partnership is a consortium of over thirty five organizations, including state natural resource and environmental protection agencies; national labs and universities; private companies working on CO{sub 2} capture, transportation, and storage technologies; utilities; oil and gas companies; nonprofit organizations; and policy/governance coordinating organizations. In an eighteen month Phase I project, the Partnership will evaluate both terrestrial and geologic sequestration options. Work will focus on five major objectives: (1) Collect data to characterize major CO{sub 2} point sources, the transportation options, and the terrestrial and geologic sinks in the region, and compile and organize this data via a geographic information system (GIS) database; (2) Address key issues affecting deployment of CT&S technologies, including storage site permitting and monitoring, injection regulations, and health and environmental risks (3) Conduct public outreach and maintain an open dialogue with stakeholders in CT&S technologies through public meetings, joint research, and education work (4) Integrate and analyze data and information from the above tasks in order to develop supply curves and cost effective, environmentally acceptable sequestration options, both near- and long-term (5) Identify appropriate terrestrial and geologic demonstration projects consistent with the options defined above, and create action plans for their safe and effective implementation A kickoff meeting for the West Coast Partnership was held on Sept 30-Oct

  10. Visual examinations of K west fuel elements

    Energy Technology Data Exchange (ETDEWEB)

    Pitner, A.L., Fluor Daniel Hanford

    1997-02-03

    Over 250 fuel assemblies stored in sealed canisters in the K West Basin were extracted and visually examined for damage. Substantial damage was expected based on high cesium levels previously measured in water samples taken from these canisters. About 11% of the inner elements and 45% of the outer elements were found to be failed in these examinations. Canisters that had cesium levels of I curie or more generally had multiple instances of major fuel damage.

  11. Whither Unified Korea? East, West or Center?

    Science.gov (United States)

    2015-02-17

    unified Korea has three broadly defined alignment options—tilt West towards the United States and Japan, tilt East towards the People’s Republic of China...PRC), or pursue neutrality /nonalignment, each with their own advantages, disadvantages, and nuanced variations. Given the range of strategic...alignment options and its tumultuous history, culture and existing security dilemma, Korea will likely opt for neutrality /nonalignment as the best option

  12. Collaborative work between the West and Asia.

    Science.gov (United States)

    Hser, Yih-Ing; Bart, Gavin; Li, Li; Giang, Le Minh

    2013-12-01

    The "Collaborative Work between the West and Asia" session was chaired by Dr. Yih-Ing Hser and had three speakers. The speakers (and their topics) were: Dr. Gavin Bart (Collaborative Addiction Research in Asian Populations Home and Abroad), Dr. Li Li (Implementing Intervention Research Projects in Asia), and Dr. Le Minh Giang (Building Research Infrastructure for International Collaborative Studies on Substance Use Disorder and HIV: The Case of Hanoi Medical University/Vietnam).

  13. WEST PIONEER WILDERNESS STUDY AREA, MONTANA.

    Science.gov (United States)

    Berger, Byron R.; Benham, John R.

    1984-01-01

    The West Pioneer Wilderness Study Area is in the Pioneer Mountains, Beaverhead County, Montana. A mineral-resource study of the area identified eight areas with molybdenum potential, four areas with gold-silver potential, one area with tungsten potential, and one area with barite potential. Several small mines were encountered, but none were accessible for the purposes of resource evaluation. No energy resources were identified in the study.

  14. SPS beam to the West Hall

    CERN Multimedia

    1976-01-01

    One of the two target stations feeding the West Hall (see Annual Report 1976). After the proton beam was split into three branches, the outer two were directed on to targets in the cast iron shielding box, the centre one passing through the box to another target station downstream. Five different targets could be put in each beam, controlled by the mechanism seen on top.

  15. The northern North Atlantic Ocean mean circulation in the early 21st century

    Science.gov (United States)

    Daniault, Nathalie; Mercier, Herlé; Lherminier, Pascale; Sarafanov, Artem; Falina, Anastasia; Zunino, Patricia; Pérez, Fiz F.; Ríos, Aida F.; Ferron, Bruno; Huck, Thierry; Thierry, Virginie; Gladyshev, Sergey

    2016-08-01

    The decadal mean circulation in the northern North Atlantic was assessed for the early 21st century from repeated ship-based measurements along the Greenland-Portugal OVIDE line, from satellite altimetry and from earlier reported transports across 59.5°N and at the Greenland-Scotland sills. The remarkable quantitative agreement between all data sets allowed us to draw circulation pathways with a high level of confidence. The North Atlantic Current (NAC) system is composed of three main branches, referred to as the northern, central and southern branches, which were traced from the Mid-Atlantic Ridge (MAR), to the Irminger Sea, the Greenland-Scotland Ridge and the subtropical gyre. At OVIDE, the northern and central branches of the NAC fill the whole water column and their top-to-bottom integrated transports were estimated at 11.0 ± 3 Sv and 14.2 ± 6.4 Sv (1 Sv = 106 m3 s-1), respectively. Those two branches feed the cyclonic circulation in the Iceland Basin and the flow over the Reykjanes Ridge into the Irminger Sea. This cross-ridge flow was estimated at 11.3 ± 4.2 Sv westward, north of 58.5°N. The southern NAC branch is strongly surface-intensified and most of its top-to-bottom integrated transport, estimated at 16.6 ± 2 Sv, is found in the upper layer. It is composed of two parts: the northern part contributes to the flow over the Rockall Plateau and through the Rockall Trough toward the Iceland-Scotland Ridge; the southern part feeds the anticyclonic circulation toward the subtropical gyre. Summing over the three NAC branches, the top-to-bottom transport of the NAC across OVIDE was estimated at 41.8 ± 3.7 Sv. Because of the surface-intensification of the southern NAC branch, the intermediate water is transported to the northeast Atlantic mostly by the northern and central branches of the NAC (11.9 ± 1.8 Sv eastward). This water circulates cyclonically in the Iceland Basin and anticyclonically in the West European Basin, with similar transport

  16. IR thermography diagnostics for the WEST project

    Energy Technology Data Exchange (ETDEWEB)

    Courtois, X., E-mail: xavier.courtois@cea.fr [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Aumeunier, M.H. [OPTIS, ZE de La Farlède, F-83078 Toulon Cedex 9 (France); Joanny, M.; Roche, H.; Micolon, F.; Salasca, S.; Balorin, C.; Jouve, M. [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France)

    2014-10-15

    Highlights: • The WEST project requires a set of three infrared diagnostics. • The tungsten divertor will be monitored by the existing diagnostic renewed. • The antennas monitoring require the development of an innovative diagnostic. • A fiber bundle will be used as image transport for the antennas monitoring. • A wide angle tangential view of the upper divertor and the first wall is studied. - Abstract: To operate long plasma discharge in tokamak equipped with actively cooled plasma facing components (PFC), infrared (IR) thermography is a key diagnostic. Indeed IR data are used for both PFC safety monitoring, to avoid material degradation and water leak, and various physics studies on plasma-wall interaction. The IR monitoring is becoming even more crucial with today metallic PFCs. This is the case for the WEST project (Tungsten (W) Environment for Steady State Tokamak), which aims at installing a W divertor in Tore Supra (TS), in order to operate the 1st tokamak with a full W actively cooled divertor in long plasma discharges. The IR thermography system for the WEST project described in this paper will consist of a set of 3 different diagnostics: (1) Six cameras located in upper ports viewing the full W divertor, which reuse a part of the existing diagnostic of TS. (2) Five novel views located behind the inner protection panels for the antennas monitoring, based on an innovative imaging fibers bundle technology. (3) A tangential wide angle view located in a median port, for the upper divertor and first wall monitoring.

  17. Cause of East-West Earth Asymmetry

    CERN Document Server

    Scalera, Giancarlo

    2015-01-01

    The different slope of the Wadati-Benioff zones oriented towards east and west is considered a main asymmetry of the Earth's globe. Under the Americas they have angles of about 30o, while under the Pacific east coasts (Asia, Japan) the angles are steeper. In the framework of plate tectonics geodynamics the cause of this difference can be identified in the tidal drag that would cause a global shift of the lithosphere towards west. But this solution has been many times criticized on the basis of the irrelevance of the tidal forces with respect to viscous friction. Instead, it is possible to show that in a different framework, in which sudden extrusions of mantle materials occur by local phase change toward a more unpacked lattice, the value of the Coriolis fictitious force can rise of several magnitude orders, becoming the main cause of the east-west asymmetry of the Wadati-Benioff zones, which might be ascribed entirely to internal causes of the planet (its rotation and geodynamics) and not to external causes ...

  18. Poverty and health in West Germany.

    Science.gov (United States)

    Helmert, U; Mielck, A; Shea, S

    1997-01-01

    The relationship between poverty and several health-related characteristics in West Germany was investigated. Data were derived from the National and Regional Health Surveys conducted in West Germany from 1984 to 1992. 25,544 males and 25,719 females with German nationality aged 25-69 years were examined. Poverty was defined as a household income of 50% less than the mean for West Germany. Multiple logistic regression analysis was used to analyze the relationship between poverty and four health variables: individual health behavior, subjective assessment of health status, cardiovascular disease risk factors, and self-reported prevalence of lifetime chronic diseases. 10.2% of males and 12.8% of females were classified as being below the poverty line. For most but not all health parameters, less favourable results were found for the segment of the population with a household income below the poverty line. The most striking poverty-related differences were observed for lack of regular sport activities, subjective health satisfaction, obesity and myocardial infarction/stroke. Significantly lower prevalence rates for study subjects below the poverty line were observed for hypercholesterolemia in females only. Allergic disorders were the only chronic diseases reported significantly less often in males and females below the poverty line. Poverty has strong effects on individual health status and the prevalence of chronic diseases. Due to the rising unemployment rates in Germany in the last years it is very likely that the strong negative consequences of poverty for health are increasing.

  19. Enhanced integrators for WEST magnetic diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Spuig, Pascal, E-mail: pascal.spuig@cea.fr [CEA IRFM, F-13108 Saint-Paul-lez-Durance (France); Kumari, Praveena [Institute for Plasma Research (IPR), Bhat, Gandhinagar District 382428 (India); Moreau, Michel; Moreau, Philippe; Le-luyer, Alain; Malard, Philippe [CEA IRFM, F-13108 Saint-Paul-lez-Durance (France)

    2015-10-15

    Highlights: • On Tokamaks, analogue integrators are key instruments. • Our analogue integrators is reliable and fast, thus relevant for fusion facilities. • Our integrator fulfils requirements for long time pulses of WEST Tokamak. • The performances are amongst the best never obtained for analogue integrators. - Abstract: The WEST project consists of implementing a divertor configuration in the Tore Supra Tokamak. This modification requires to renew the magnetic diagnostics and especially adding new magnetic sensors in the divertor region. This has provided an opportunity to consider some enhancements to the existing integrator modules of the magnetic diagnostics. Two prototypes have been produced using different combinations of technical solutions, aiming to achieve lower drift and higher common mode rejection ratio (CMRR). This paper presents the explored and tested ways we followed in order to create enhanced analogue integrators for long pulses. The results of extensive and comprehensive tests are summarized. The achieved performances are analyzed regarding the WEST project specifications and furthermore, the latest ITER requirements for magnetic diagnostics integrators are also considered.

  20. Seasonal Variability of South Atlantic Central Water

    Science.gov (United States)

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

    2013-05-01

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