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Sample records for luzon strait westward

  1. Structure and Variability of Internal Tides in Luzon Strait

    Science.gov (United States)

    2016-09-14

    Sponsor ON R. (I) .2- 2,6— approval obtained yes X no Title of Parer or Presentation Structure and Variability of Internal Tides in Luzon Strait...ision, Div v Author, Code HQ-NRL 55118 (Rev. 12-98) (e) THIS FORM CANCELS AND SUPERSEDES ALL PREVIOUS VERSIONS Structure and Variability of Internal ... internal tides that radiate westward into the South China Sea and eastward into the western Pacific. Intrusions of the Kuroshio and strong mesoscale

  2. An updated examination of the Luzon Strait transport

    Science.gov (United States)

    Hsin, Yi-Chia; Wu, Chau-Ron; Chao, Shenn-Yu

    2012-03-01

    Despite numerous previous estimates of Luzon Strait transport (LST), we attempt an update using a fine-resolution model. With these improvements, the circulation in and around Luzon Strait shows up rather realistically. Intrusion of a Kuroshio meander into the South China Sea (SCS) is seasonally varying. The LST, especially in the upper ocean, caused by a small difference between the large meander inflow and outflow, is also seasonally varying and subject to large standard deviation. The annual mean LST is estimated to be westward (-4.0 ± 5.1 Sv) along 120.75°E. We have also conducted process of elimination experiments to assess the relative importance of open ocean inflow/outflow, wind stress, and surface heat flux in regulating LST and its seasonality. The East Asian monsoon winds stand out as the predominant forcing. Without it, the upper ocean LST changes from westward to eastward (ranging up to 4 Sv) and, with misaligned seasonality, triggering an inflow from the Mindoro Strait to the SCS to replenish the water mass loss. Discounting monsoon winds, sea level in the Sulu Sea is generally higher because it receives the Indonesian Throughflow before the SCS, which causes an inflow from the Sulu Sea to the SCS. On the other hand, the annual mean wind from the northeast invites outflow from the SCS to the Sulu Sea (or inflow from the Luzon Strait). Weighing the two competing factors together, we see the cessation of northeast monsoon as a condition favorable for the Luzon Strait outflow or the Mindoro Strait inflow.

  3. Optimal estimation of zonal velocity and transport through Luzon Strait using variational data assimilation technique

    Institute of Scientific and Technical Information of China (English)

    LAN Jian; BAO Xianwen; GAO Guoping

    2004-01-01

    A P-vector method was optimized using variational data assimilation technique, with which the vertical structures and seasonal variations of zonal velocities and transports were investigated. The results showed that westward and eastward flowes occur in the Luzon Strait in the same period in a year. However the net volume transport is westward. In the upper level (0m - -500m),the westward flow exits in the middle and south of the Luzon Strait, and the eastward flow exits in the north. There are two centers of westward flow and one center of eastward flow. In the middle of the Luzon Strait, westward and eastward flowes appear alternately in vertical direction. The westward flow strengthens in winter and weakens in summer. The net volume transport is strong in winter (5.53 Sv) but weak in summer (0.29 Sv). Except in summer, the volume transport in the upper level accounts for more than half of the total volume transport (0m - bottom). In summer, the net volume transport in the upper level is eastward (1.01 Sv), but westward underneath.

  4. Optimal estimation of absolute geostrophic velocity field in vicinity of the Luzon Strait using variational data assimilation technique

    Institute of Scientific and Technical Information of China (English)

    兰健; 王东晓

    2002-01-01

    A P - vector method is opt'inized using the variational data assimilation technique (VDAT). The absolute geostrophic velocity fields in the vicinity of the Luzon Strait (LS) are calculated, the spatial structures and seasonal variations o{ the absolute geostrophic velocity field are investigated. Our results show that the Kuroshio enters the South China Sea (SCS) in the south and middle of the Luzon Strait and flows out in the north, so the Kuroshio makes a slight clockwise curve in the Luzon Strait, and the curve is strong in winter and weak in summer. During the winter, a westward current appears in the surface, and locates at the west of the Luzon Strait. It is the north part of a cyclonic gyre which exits in the northeast of the SCS; an anti-cyclonic gyre occurs on the intermediate level, and it exits in the northeast of the SCS, and an eastward current exits in the southeast of the anti-cyclonic gyre.

  5. The bimodality of the Luzon Strait deep water

    Institute of Scientific and Technical Information of China (English)

    WU Qingsong; ZHAO Jianru; ZHANG Junbiao; SHI Weiyong; LIU Chunqiu

    2014-01-01

    Combined conductivity-temperature-depth (CTD) casts and Argo profiles, 3 086 historical hydrocasts were used to quantify the water column characteristics in the northern South China Sea (SCS) and its adjacent waters. Based on a two-dimensional“gravest empirical mode”(GEM), a gravitational potential (׋, a verti-cally integrated variable) was used as proxy for the vertical temperature profiles TG(p,׋).׋integrated from 8 MPa to the surface shows a close relationship with the temperature, except in the deep layer greater than 15 MPa, which was caused by the bimodal deep water in the region. The GEM temperature profiles successfully revealed the bimodality of the Luzon Strait deep water, that disparate hydrophic vertical profiles can pro-duce distinct specific volume anomaly (į) in the SCS and the western Philippine Sea (WPS), but failed in the Luzon Strait, where different temperature profiles may produce a sameį. A significant temperature diver-gence between the SCS water and the WPS water confirmed that the bimodal structure is strong. The deep-water bifurcation starts at about 15 MPa, and gets stronger with increasing depth . As the only deep channel connecting the bimodal-structure waters, water column characteristics in the Luzon Strait is in between, but much closer to the SCS water because of its better connectivity with the SCS. A bimodal temperature structure below 15 MPa reveals that there was a persistent baroclinic pressure gradient driving flow through the Luzon Strait. A volume flux predicted through the Bashi Channel with the hydraulic theory yields a value of 5.62×106 m3/s using all available profiles upstream and downstream of the overflow region, and 4.03×106 and 2.70×106 m3/s by exclusively using the profiles collected during spring and summer, respectively. No volume flux was calculated during autumn and winter because profiles are only available for the upstream of the Bashi Channel during the corresponding period.

  6. Three-dimensional numerical simulation of M2 internal tides in the Luzon Strait

    Institute of Scientific and Technical Information of China (English)

    LI Bingtian; CAO Anzhou; LV Xianqing

    2015-01-01

    A three-dimensional isopycnic-coordinate internal tidal model is employed to investigate the generation, propagation, vertical structure and energy conversion of M2 internal tides in the Luzon Strait (LS) with mooring observations. Simulated results, especially the tidal current amplitudes, agree well with observations, demonstrating the reasonability and accuracy of the model. Results indicate that M2 internal tides mainly propagate into three directions horizontally, i.e., eastward towards the western Pacific Ocean, westward towards the Dongsha Island and southwestward towards the South China Sea Basin. In the horizontal direction, tidal current amplitudes decrease as distance increases away from the LS; in the vertical direction, they show an obvious decreasing tendency with depth. Between the double ridges of the LS, a clockwise gyre of M2 baroclinic energy flux appears, which is caused by reflections of M2 internal tides at supercritical topographies, and resonance of M2 internal tides happens along 19.5° and 21.5°N due to the heights and separation distance of the double ridges. The total energy conversion in the LS is about 14.20 GW.

  7. Generation and Evolution of Internal Waves in Luzon Strait

    Science.gov (United States)

    2015-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Generation and Evolution of Internal Waves in Luzon...inertial waves , nonlinear internal waves (NLIWs), and turbulence mixing––in the ocean and thereby help develop improved parameterizations of mixing for...ocean models. Mixing within the stratified ocean is a particular focus as the complex interplay of internal waves from a variety of sources and

  8. Numerical study on the interactions between the Kuroshio current in the Luzon Strait and a mesoscale eddy

    Science.gov (United States)

    Kuo, Yi-Chun; Chern, Ching-Sheng; Zheng, Zhe-Wen

    2017-02-01

    The Luzon Strait (LS) connects the northwestern Pacific Ocean and the South China Sea (SCS) and is the western boundary gap for the Kuroshio current (KC). Satellite observations indicate that a cyclonic mesoscale eddy can trigger westward extension of the KC into the SCS and shed a smaller anticyclonic eddy to the west of the LS. We used a nonlinear reduced-gravity (primitive equation) model to study this phenomenon and analyzed the dynamic process. The location of the collision between the eddy and the KC could be critical for varying the circulation in the LS. The eddy's deformation rate, associated with its decaying speed, is also closely related to the location of the eddy during collision. When a cyclonic eddy moved from a region to the east of the Luzon Island toward the LS, the KC intruded into the SCS with growing negative vorticity during the collision of the eddy and KC. This tendency for negative vorticity is attributed to the beta effect and squeezing of the planetary vorticity caused by the flow divergence. As the eddy dissipated, the KC in the LS recovered its original pattern. When the collision of the eddy occurred at the center of the LS, the momentum balance of the KC loop was dominated by the inertial term, and the circulation in the LS remained in a leaping state.

  9. State analysis using the Local Ensemble Transform Kalman Filter (LETKF) and the three-layer circulation structure of the Luzon Strait and the South China Sea

    Science.gov (United States)

    Xu, Fang-Hua; Oey, Lie-Yauw

    2014-06-01

    A new circulation model of the western North Pacific Ocean based on the parallelized version of the Princeton Ocean Model and incorporating the Local Ensemble Transform Kalman Filter (LETKF) data assimilation scheme has been developed. The new model assimilates satellite data and is tested for the period January 1 to April 3, 2012 initialized from a 24-year simulation to estimate the ocean state focusing in the South China Sea (SCS). Model results are compared against estimates based on the optimum interpolation (OI) assimilation scheme and are validated against independent Argo float and transport data to assess model skills. LETKF provides improved estimates of the western North Pacific Ocean state including transports through various straits in the SCS. In the Luzon Strait, the model confirms, for the first time, the three-layer transport structure previously deduced in the literature from sparse observations: westward in the upper and lower layers and eastward in the middle layer. This structure is shown to be robust, and the related dynamics are analyzed using the results of a long-term (18 years) unassimilated North Pacific Ocean model. Potential vorticity and mass conservations suggest a basin-wide cyclonic circulation in the upper layer of the SCS ( z > -570 m), an anticyclonic circulation in the middle layer (-570 m ≥ z > -2,000 m), and, in the abyssal basin (reduced-gravity model as being caused by overflow over the deep sill of the Luzon Strait, coupled with intense, localized upwelling west of the strait.

  10. Eddy formation and surface flow field in the Luzon Strait area during the summer of 2009

    Science.gov (United States)

    Liu, Ze; Hou, Yijun; Xie, Qiang

    2015-09-01

    The formation of mesoscale eddies and the structure of the surface flow field in the Luzon Strait area were examined using in-situ CTD data, Argo float data, and multi-satellite remote sensing data collected from May to August 2009. The results show that vigorous water exchange between Kuroshio water and South China Sea (SCS) water began to emerge over the 200 m water column throughout the strait. Based on an objective definition of surface currents, float A69 tracked an anti-cyclonic eddy southwest of Taiwan Island under a Lagrangian current measurement. The salinity inside the anti-cyclonic eddy was higher than in typical SCS water but lower than in Kuroshio mainstream water, indicating that this eddy was induced by Kuroshio frontal intrusion through the Luzon Strait and into the SCS. From hydrographic data, we propose that continuous horizontal diffusion with high-salinity characteristics in the subsurface layer could extend to 119°E or even further west. The high-temperature filament, large positive sea level anomaly and clockwise geostrophic current all confirmed the existence of this warm eddy in May and June. A strongly negative wind stress curl maintained the eddy until it died. The surface flow field during July and August was rather complicated. Float A83 described an east-west orientated shuttle run in the 20°N section that was not reported by previous studies. At the same time, float A80 indicated a Kuroshio bend into the north-central region of Luzon Strait but it did not cross 120.5°E. The water mass rejoining the Kuroshio mainstream from the southern tip of Taiwan Island was less saline, indicating an entrainment of water from SCS by the Kuroshio bend.

  11. A numerical study of the South China Sea deep circulation and its relation to the Luzon Strait transport

    Institute of Scientific and Technical Information of China (English)

    袁东亮

    2002-01-01

    A fine-resolution MOM code is used to study the South China Sea basin-scale circulation and its relation to the mass transport through the Luzon Strait. The modal domain includes the South China Sea, part of the East China Sea, and part of the Philippine Sea so that the currents in the vicinity of the Luzon Strait are free to evolve. In addition, all channels between the South China ,Sea and the Indonesian seas are closed so that the focus is on the Luzon Strait transport. The model is driven by specified Philippine Sea currents and by surface heat and salt flux conditions. For simplicity, no windstress is applied at the surface.The simulated Luzon Strait transport and the South China Sea circulation feature a sandwich vertical structure from the surface to the bottom. The Philippine Sea water is simulated to enter the South China Sea at the surface and in the deep ocean and is carried to the southern basin by western boundary currents. At the intermediate depth, the net Luzon Strait transport is out of the South China Sea and is fed by a western boundary current flowing to the north at the base of the thermocline. Corresponding to the western boundary currents, the basin circulation of the South China Sea is cyclonic gyres at the surface and in the abyss but an anti-cyclonic gyre at the intermediate depth. The vorticity balance of the gyre circulation is between the vortex stretching and the meridional change of the planetary vorticity.Based on these facts, it is hypothesized that the Luzon Strait transports are determined by the diapycnal mixing inside the entire South China Sea. The South China Sea plays the role of a "mixing mill" that mixes the surface and deep waters to return them to the Luzon Strait at the intermediate depth. The gyre structures are consistent with the Stommel and Arons theory (1960), which suggests that the mixlng-induced circulation inside the South China Sea should be cyclonic gyres at the surface and at the bottom but an anti

  12. Large-scale, realistic laboratory modeling of M2 internal tide generation at the Luzon Strait

    CERN Document Server

    Mercier, Matthieu J; Helfrich, Karl; Sommeria, Joël; Viboud, Samuel; Didelle, Henri; Saidi, Sasan; Dauxois, Thierry; Peacock, Thomas

    2015-01-01

    The complex double-ridge system in the Luzon Strait in the South China Sea (SCS) is one of the strongest sources of internal tides in the oceans, associated with which are some of the largest amplitude internal solitary waves on record. An issue of debate, however, has been the specific nature of their generation mechanism. To provide insight, we present the results of a large-scale laboratory experiment performed at the Coriolis platform. The experiment was carefully designed so that the relevant dimensionless parameters, which include the excursion parameter, criticality, Rossby, and Froude numbers, closely matched the ocean scenario. The results advocate that a broad and coherent weakly nonlinear, three-dimensional, M2 internal tide that is shaped by the overall geometry of the double-ridge system is radiated into the South China Sea and subsequently steepens, as opposed to being generated by a particular feature or localized region within the ridge system.

  13. Analysis of longer period variation of the Kuroshio Current intrusion into the Luzon Strait using rectified wavelet power spectra

    Science.gov (United States)

    Yuan, Yaochu; Yang, Chenghao; Tseng, Yu-heng; Zhu, Xiao-Hua; Wang, Huiqun; Chen, Hong

    2017-08-01

    Longer period variation of the Kuroshio into the Luzon Strait (LS) was identified using acoustic Doppler current profiler (ADCP) observations as well as pressure and temperature time series data recorded by two TDs (manufactured by the RBR Ltd.) at mooring station N2 (20°40.441‧N, 120°38.324‧E). The ADCP was deployed at depths of 50-300 m between July 7, 2009 and April 10, 2011, and the TDs at around 340 and 365 m between July 9, 2009 and July 9, 2011. Observations provide strong evidence of longer period variation of the Kuroshio into the LS using the Vector rotary spectra (VRS) and Rectified wavelet power spectra analysis (RWPSA). RWPSA of the observations allowed the identification of two types of dominant periods. The first type, with the strongest power spectral density (PSD), had a dominant period of 112 d and was found throughout the upper 300 m. For example, the maximum PSD for western and northern velocity components time series were 3800 and 3550 at 50 m, respectively. The maximum power spectral density decrease with deeper depths, i.e., the depth dependence of maximum PSD. The 112 d period was also identified in the pressure and temperature time series data, at 340 m and 365 m. Combined RWPSA with VRS and mechanism analysis, it is clear that the occurrence of the most dominant period of 112 d in the upper 300 m is related to the clockwise meandering of the Kuroshio into the LS, which is caused by westward propagating stronger anticyclonic eddies from the interior ocean due to the interaction of Rossby eddies with the Kuroshio. The second type of dominant period, for example a 40 d period, is related to the anticlockwise meandering of the Kuroshio. The final dominant period of 14 d coincides with the fortnightly spring-neap tidal period.

  14. A double-index method to classify Kuroshio intrusion paths in the Luzon Strait

    Science.gov (United States)

    Huang, Zhida; Liu, Hailong; Hu, Jianyu; Lin, Pengfei

    2016-06-01

    A double index (DI), which is made up of two sub-indices, is proposed to describe the spatial patterns of the Kuroshio intrusion and mesoscale eddies west to the Luzon Strait, based on satellite altimeter data. The area-integrated negative and positive geostrophic vorticities are defined as the Kuroshio warm eddy index (KWI) and the Kuroshio cold eddy index (KCI), respectively. Three typical spatial patterns are identified by the DI: the Kuroshio warm eddy path (KWEP), the Kuroshio cold eddy path (KCEP), and the leaking path. The primary features of the DI and three patterns are further investigated and compared with previous indices. The effects of the integrated area and the algorithm of the integration are investigated in detail. In general, the DI can overcome the problem of previously used indices in which the positive and negative geostrophic vorticities cancel each other out. Thus, the proportions of missing and misjudged events are greatly reduced using the DI. The DI, as compared with previously used indices, can better distinguish the paths of the Kuroshio intrusion and can be used for further research.

  15. Response of the Kuroshio Current to Eddies in the Luzon Strait

    Institute of Scientific and Technical Information of China (English)

    ZHAO Jie; LUO De-Hai

    2010-01-01

    The impact of eddies on the Kuroshio Current in the Luzon Strait(LS)area is investigated by using the sea surface height anomaly(SSHA)satellite observation data and the sea surface height(SSH)assimilation data.The influence of the eddies on the mean current depends upon the type of eddies and their relative position.The mean current is enhanced(weakened)as the cyclonic(anticyclonic)eddy becomes slightly far from it,whereas it is weakened(enhanced)as the cyclonic(anticyclonic)eddy moves near or within the position of the mean current;this is explained as the eddy-induced meridional velocity and geostrophic flow relationship.The anticyclonic(cyclonic)eddy can increase(decrease)the mean meridional flow due to superimposition of the eddy-induced meridional flow when the eddy is within the region of the mean current.However,when the eddy is slightly far from the mean current region,the anticyclonic(cyclonic)eddy tends to decrease(increase)the zonal gradient of the SSH,which thus results in weakening(strengthening)of the mean current in the LS region.

  16. Variability of the currents in the Luzon Strait during spring of 2002 obtained from observations and satellite geostrophic currents and spectral analyses

    Institute of Scientific and Technical Information of China (English)

    YUAN YaoChu; LIAO GuangHong; WANG HuiQun; LOU RuYun; CHEN Hong

    2009-01-01

    The structure and variability of the currents in the Luzon Strait during spring of 2002 are studied, based on the current measurements at the average position of the mooring station (20°49'57"N, 120°48'12"E) from 03 17 to 04 15, 2002, satellite geostrophic currents in the Luzon Strait, and the spectral analyses, using the maximum entropy method. The subtidal currents at the mooring station show de-creased amplitudes downward with an anti-cyclonic rotation, suggesting that the currents enter and exit the South China Sea in the upper and intermediate layers, respectively. The vertical structure of the currents in the Luzon Strait suggests strongly the sandwiched structure of the LST, even though the bottom part of the profile is not resolved by the observational grid. The spectral analyses show the following periods of significant spectral peaks: (1) the tidal currents variability in the vertical direction; (2) the period about 4-6 d for the two cases of frequency f>0 and f0 and f<0 at the 200, 500 and 800 m levels, namely the Luzon Strait currents exhibit significant synoptical variability throughout the water column up to 800 m deep. Both direct current measurements and in situ hydrographic and satellite survey suggest no Kuroshio loop current in the Luzon Strait during the spring of 2002.

  17. Variability of the currents in the Luzon Strait during spring of 2002 obtained from observations and satellite geostrophic currents and spectral analyses

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The structure and variability of the currents in the Luzon Strait during spring of 2002 are studied, based on the current measurements at the average position of the mooring station (20°49′57"N, 120°48′12"E) from March 17 to April 15, 2002, satellite geostrophic currents in the Luzon Strait, and the spectral analyses, using the maximum entropy method. The subtidal currents at the mooring station show de-creased amplitudes downward with an anti-cyclonic rotation, suggesting that the currents enter and exit the South China Sea in the upper and intermediate layers, respectively. The vertical structure of the currents in the Luzon Strait suggests strongly the sandwiched structure of the LST, even though the bottom part of the profile is not resolved by the observational grid. The spectral analyses show the following periods of significant spectral peaks: (1) the tidal currents variability in the vertical direction; (2) the period about 4-6 d for the two cases of frequency f >0 and f<0 at the 200 and 500 m levels, but at the 800 m level only for the case of f >0; (3) The fluctuation in the period range is about 2-3 days for the two cases of f >0 and f<0 at the 200, 500 and 800 m levels, namely the Luzon Strait currents exhibit significant synoptical variability throughout the water column up to 800 m deep. Both direct current measurements and in situ hydrographic and satellite survey suggest no Kuroshio loop current in the Luzon Strait during the spring of 2002.

  18. Summer Kuroshio Intrusion through the Luzon Strait confirmed from observations and a diagnostic model in summer 2009

    Science.gov (United States)

    Yuan, Yaochu; Liao, Guanghong; Yang, Chenghao; Liu, Zenghong; Chen, Hong; Wang, Zhang-Gui

    2014-02-01

    Based on current measurements recorded at Mooring Station N2 (20°40.441‧N, 120°38.324‧E), hydrographic data and Argo observations in the period starting from July 2009, a diagnostic model with a modified inverse method is used to study the circulation in the Luzon Strait (LS). A number of new circulation features in the LS are found as follows. (1) Both observed and modeled currents show that the intruded Kuroshio flow northwestward through the LS into the South China Sea (SCS) in the upper 400 m during July 2009. (2) The diagnostic model confirms that the Kuroshio is located in the area east of 121°20‧E and west of 122°20‧E at 20°00‧N. There is a meso-scale cyclonic eddy at both the surface and 1000 m depth in the area west of the Kuroshio near 20°00‧N. The meso-scale cyclonic eddy forced the Argo float 1 to make the cyclonic trajectory. Then, the Argo float 1 went into the area of the western Kuroshio. The Argo float 1 was tracked as the flow moved northwestward into the SCS across the LS in July and August, 2009, reflecting the northwestward flow at both the surface and 1000 m depth, which coincided with modeled currents. These results confirm the northwestward Kuroshio intrusion into the SCS across the LS in summer 2009 for the first time. (3) From the dimensional analysis for the equation of stream function, it is seen that the joint effect of the baroclinity and relief (JEBAR) and the β-effect are two important mechanisms on the Kuroshio intrusion into the SCS in this period. This summer Kuroshio intrusion results from the weaker upstream Kuroshio transport in summer 2009 (El Niño initiating period) due to inertia effects and is associated with a weak volume transport across the LS (2.15 × 106 m3 s-1 westward). (4) After comparison of the dynamics of the Kuroshio intrusion during October 2008 and summer 2009, it is clear that these were influenced by the seasonal variability due to the monsoon winds and the interannual variation resulting

  19. Preliminary study of zooplankton community in the Luzon strait%吕宋海峡浮游动物群落结构的初步研究

    Institute of Scientific and Technical Information of China (English)

    连喜平; 谭烨辉; 刘永宏; 黄良民; 陈清潮; 周林滨

    2013-01-01

    Different water masses have distinct natural physical and chemical properties, which may influence the zooplankton community structure. In order to improve our understanding of the relationship between zooplankton and water mass, zooplankton was sampled at 14 stations between 15th August, and 19th September, 2008 in the Luzon Strait. A total of 257 species and 12 groups of planktonic larvae were identified. Copepod was the most dominant species, followed by medusa. Species richness and diversity indices in the west of Luzon Strait were higher than that in the east of Luzon Strait. The average abundance of zooplankton in Luzon strait was 16.76 11.36 ind./m3. Zooplankton abundance in the west of Luzon Strait was higher than that in the east of Luzon Strait. Cluster analysis showed that there was difference in zooplankton community between the both sides of Luzon strait. The differences of zooplankton communities indicated that different water masses can influences zooplankton species composition and spatial distribution.%不同理化性质的水团影响浮游动物种类组成和群落结构.为了探讨吕宋海峡的环境对浮游动物群落结构的影响,于2008年8月15日至9月15日对吕宋海峡浮游动物的种类组成和丰度分布进行了调查和分析.共鉴定出浮游动物257种和浮游幼虫12个类群,吕宋海峡西部海域浮游动物种类数和多样性比中东部海域的高.浮游动物平均丰度为(16.76±11.36) ind./m3 .其中,吕宋海峡西部海域浮游动物平均丰度高于吕宋海峡中东部海域.聚类分析结果表明,吕宋海峡浮游动物可分为两个类群,一类为分布于吕宋海峡的中东部,受黑潮水影响的类群;另一类为分布于吕宋海峡西部,受南海水影响的类群.吕宋海峡浮游动物群落结构反映了该海域浮游动物的种类组成和分布受不同性质水团的调控.

  20. Currents in the Luzon Strait during the spring of 2002: observation and computation by modified inverse model

    Institute of Scientific and Technical Information of China (English)

    YUAN Yaochu; LOU Ruyun; LIU Yonggang; SU Jilan; WANG Kangshan; CHEN Hong

    2005-01-01

    On the basis of the current measurements at 200,500 and 800 m from moored current meters with the time series data from March 17 to April 15 at the mooring station (20°49′57″N, 120°48' 12″E ) and the hydrographic data obtained in the Luzon Strait during the spring of 2002 cruise, the circulation in the investigated area is computed by using the modified inverse method. The major observed results are as follows: (1) the average velocity and the flow direction in the observing days are (47.4 cm/s, 346°) at the 200 m level. The aver age velocity in the observing days is (20.3 cm/s, 350°) at the 500 m level. These mean that the Kuroshio intrudes into the South Chin Sea to flow northwestward through the Luzon Strait at 200 and 500 m levels. (2) The average velocity in the observing days is (1.2cm/s, 35°) at the 800 m level, I. E., its direction is northeastward. This means that the flow condition at the 800 m level very differs from that at the 200 and 500 m levels. (3) There is the high density and cold water (HDCW) in the middle of western part of in the investigated region, and its center is located near the hydrological station 3 at Section A. (4) There is the lower density and warm water (LDWW) in the southeastern part of investigated region. (5) The currents in April 2002 are stronger than those in March 2002.The major computed results are as follows: (1) The northwestward and southeastward VTs through Section B are 32.48×106 m3/s (inclusive of VT ofanticyclonic eddy) and 3.34×106m3/s, respectively. The net northwestward VT through Section B in the investigated area is about 29.14×106 m3/s. (2) The eastern and western VTs through Section A are about 16.71× 106 and 8.57×106 m3/s, respectively. Thus,the net eastward VT through Section A is about 8.14×106 m3/s. (3) The net northward VT through Section M is about 24.68×106 m3/s.(4) After about 24.68×106 m3/s flows through Section M, most of it, about 16.54×106 m3/s, flows northward through the

  1. The diel vertical migration of sound scatterers observed by an acoustic Doppler current profiler in the Luzon Strait from July 2009 to April 2011

    Institute of Scientific and Technical Information of China (English)

    YANG Chenghao; LIAO Guanghong; YUAN Yaochu; CHEN Hong; ZHU Xiaohua

    2013-01-01

    Acoustic Doppler current profiler (ADCP) receives echoes from sound scatterers, then their speed is calcu-lated by the Doppler effect. In the open ocean, most of these backscatterers are from the plankton. The sound scatterers descend down to depth at around dawn, their mean speed is 2.9 cm/s, then they ascend up to the surface layer at around dusk with a mean speed of 2.1 cm/s, in the Luzon Strait. The descending speed is faster, which suggests that this zooplankton population may accelerate its downward migration under the action of the gravity. The vertical distribution of a mean volume backscattering strength (MVB-S) in the nighttime has two peaks, which locate near the upper and lower boundary layers of halocline, respectively. However, the backscatterers only aggregate near the surface layer in the daytime. The diel ver-tical migration (DVM) of sound scatterers has several characteristic patterns, it is stronger in summer, but weaker in winter, and the maximum peak occurs in September. The DVM occurrence is synchronous with the seawater temperature increasing at around dawn and dusk, it may affect the ocean mixing and water stratification.

  2. Ra-228, Ra-226, Pb-210 and Po-210 variations in the water columns and the surface water plankton in the Luzon Strait and northern South China Sea

    Science.gov (United States)

    Chung, Y.; Lin, C.; Wang, P.; Su, Y.

    2006-12-01

    Profiles of Ra-228, Ra-226, Pb-210 and Po-210 were measured in the Luzon Strait (LS) and northern South China Sea (SCS) areas to delineate the exchanges between the western Philippine Sea (WPS) and the northern SCS waters across the LS. Plankton samples were also collected for Po-210 and Pb-210 measurements to assess the balance between the Po-210 excess over Pb-210 in the plankton and the deficit in the surface water. Profiles of Ra-228 and Ra-226 seem to indicate the out flow of the SCS water below the salinity minimum and above around 1500m depth, below which the WPS water flows into the SCS through the LS above a sill depth of about 2600m. This is consistent with previous studies conducted in the area. All the Pb-210 profiles show a strong subsurface maximum with higher activity in the LS area. This maximum is in large excess over its parent, Ra-226 due to atmospheric input. Po-210 profiles generally follow the associated Pb-210 profiles but with lower activities, showing Po-210 deficiency. Po-210 is strongly enriched over Pb-210 in the plankton samples with an activity ratio generally over 10 and up to 40. Both nuclides in the plankton are higher in the LS area, a trend similar to the surface water. The Po-210 excess in the plankton can account for at least 70 percent of the surface water deficit, part of which may be removed by sinking particles.

  3. The Battle for Leyte Gulf. October 1944. Strategical and Tactical Analysis. Volume V. Battle of Surigao Strait October 24th-25th

    Science.gov (United States)

    1958-01-01

    320 PT 328 reports sighting gunfire south in Surigao Strait 320 (b) Operations of MB’s Mindanao Sea uneventful 320 f CHAPTER XII - JAPANESE OPERATIONS...embracing Luzon Strait and extending westward to Hainan] island- Plate XII ) that (a) China-based planes reported shipping along the boundary between the...war proceeding to close TG 38.2 at twenty- six knots and would launch a deck-load strike against the "Jap fleet vicinity Tablas Island."* At 1324 he

  4. Solitary Wave Generation Dynamics at Luzon Strait

    Science.gov (United States)

    2009-08-27

    ð2LÞ for the wes- tern stratification are close to those for case 1 shown in Fig. 21(b). Comparisons of weakly nonlinear KdV with extended KdV , Miy...and Camasa, 1999 exhibit less decrease in wavelength versus amplitude relative to KdV or extended KdV . KdV and extended KdV models exhibit a decrease...as a function of amplitude between the extended KdV and nonlinear models can be as large as 50% less for extended KdV Brandt et al., 1997. 5

  5. Generation and Evolution of Internal Waves in Luzon Strait

    Science.gov (United States)

    2012-09-30

    S9 (19.34° N, 121.03° E) taken by Matthew Alford. The diurnal tidal energy flux is 14 kW/m at mooring S9 and 16 kW/m at the TOWCTD site. The...the oceanic response to and recovery from tropical cyclones in the western Pacific using long-term mooring observations and an array of EM-APEX floats...between model predictions (black arrows: Harper Simmons), S9 mooring observations (blue arrows: Matthew Alford), and TOWCTD observations (red arrows

  6. Generation and Evolution of Internal Waves in Luzon Strait

    Science.gov (United States)

    2016-03-01

    represent isopycnals. REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704-0188 Public reporting burden for this collection of information is...2. REPORT TYPE Final Technical 3. DATES COVERED (From - To) 1 Jan 2009 – 31 Dec 2015 4. TITLE AND SUBTITLE Generation and Evolution of

  7. Laboratory Modeling of Internal Wave Generation in Straits

    Science.gov (United States)

    2014-06-13

    Peacock 2010). 3. The suitability of the double ridge configuration of the Luzon Strait to give rise to resonant forcing of the semi-diurnal...Figure 6. 6 Figure 6: PIV visualization of the magnitude of the in-plane velocity of the 3D conical internal wave field generated by a...Visualization of the conical 3D internal wave field generated by an oscillating sphere using stereo-PIV, Experiments in Fluids, 54, 1454. Mathur

  8. STRAIT REVIEW

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Relations across the Taiwan Strait got off the ground last year with direct flights between the mainland and Taipei, though interaction at an official level remained turbulent. The cross-strait relationship, which continues to be an unrelenting focus of government attention, has a complicated background and unclear future, a situation echoed in recent Chinese media reports on topics relating to Taiwan. While seemingly innocuous in subject matter-charter flights, cuddly pandas- the back-story to the headl...

  9. Strait Stance

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Despite rebukes against pro-independence Taiwan leader Chen Shui-bian's move to disrupt peace and stability across the Taiwan Strait, the mainland remains active in pushing forward links with the island. Sun Shengliang, a research fellow at the Institute of Taiwan Studies under the Chinese Academy of Social Sciences, analyzes the mainland's stance and efforts in cross-strait relations. Following are excerpts of his article carried in the People's Daily Overseas Edition:

  10. What processes control the net currents through shallow straits? A review with application to the Bohai Strait, China

    Science.gov (United States)

    Li, Yanfang; Wolanski, Eric; Zhang, Hua

    2015-06-01

    We review the key processes controlling the net water circulation in shallow straits. The circulation is mainly barotropic, driven by the difference in mean sea level and tides on either side of the strait, the wind, the meandering of the currents in the adjoining seas, the bathymetry including the shape and width of the mouths and the presence of narrows, shoals, sills, islands, and lateral embayments. As the oceanography forcing can be non-synchronised on either side of the strait, the resulting net currents through the strait may appear chaotic. We apply these findings to the net circulation through the Bohai Strait in China using local wind, remote-sensing data of currents and sea level, and a hydrodynamic model. The net currents through the Bohai Strait were episodic. They were largest during winter storms when the wind generated a cyclonic coastal current in the northern Yellow Sea that flowed across the width of the Bohai Strait. Like the Luzon Strait, this current meandered and a branch of the current intruded into the northern Bohai Strait along the deeper channel. The wind set-up in the Bohai Sea and the wind-driven longshore current in the southern Bohai Sea generated a seaward flow through the southern Bohai Strait, somewhat like in Irbe Strait. As with the straits of the Seto Inland Sea, stagnation occurred in some embayments. As in the Torres Strait, the islands in the southern Bohai Strait retarded the net flow and increased the width of the outflow zone. These flows were also modulated at very long periods (∼60 days) by long waves in the Yellow Sea, possibly generated by meandering of the Kuroshio Current that created an additional sea level slope through the strait. The transit time in the Bohai Strait was 60 and 10 days, respectively, during calm weather and winter storms. The residence time in the Bohai Sea was estimated to be about 1.68 years by the LOICZ model and 1.56 years by the hydrodynamic model, and the influence of the river runoff

  11. Early westward flow across the Tasman Gateway

    Directory of Open Access Journals (Sweden)

    W. P. Sijp

    2015-10-01

    Crucially, in this situation where Australia is still situated far south and almost attached to Antarctica, the Drake Passage must be sufficiently restricted to allow the prevailing easterly wind pattern to set up this southerly restricted westward flow. In contrast, an open Drake Passage, to 517 m depth, leads to an eastward flow, even when the Tasman Gateway and the Australo-Antarctic gulf are entirely contained within the latitudes of easterly wind.

  12. Lagrangian study of temporal changes of a surface flow through the Kamchatka Strait

    CERN Document Server

    Prants, S V; Uleysky, M Yu; Budyansky, M V

    2014-01-01

    Using Lagrangian methods we analyze a 20-year-long estimate of water flux through the Kamchatka Strait in the northern North Pacific based on AVISO velocity field. It sheds new light on the flux pattern and its variability on annual and monthly time scales. Strong seasonality in surface outflow through the strait could be explained by temporal changes in the wind stress over the northern and western Bering Sea slopes. Interannual changes in a surface outflow through the Kamchatka Strait correlate significantly with the Near Strait inflow and Bering Strait outflow. Enhanced westward surface flow of the Alaskan Stream across the $174^\\circ$ E section in the northern North Pacific is accompanied by an increased inflow into the Bering Sea through the Near Strait. In summer, the surface flow pattern in the Kamchatka Strait is determined by passage of anticyclonic and cyclonic mesoscale eddies. The wind stress over the Bering basin in winter - spring is responsible for eddy generation in the region.

  13. The summer-fall anticyclonic eddy west of Luzon: Structure and evolution in 2012 and interannual variability

    Science.gov (United States)

    Wang, Xia; Fang, Wendong; Chen, Rongyu; Cai, Shuqun

    2017-08-01

    The Conductivity-Temperature-Depth (CTD) and acoustic Doppler current profiler (ADCP) measurements along 18°N off the western Luzon in the South China Sea (SCS), collected during a cruise from August 12-14, 2012, were used to explore the vertical structure of an anticyclonic eddy (AE) during the observational period. Further, the French Archiving, Validation and Interpretation of Satellite Oceanographic data (AVISO) sea level anomaly (SLA) and corresponding anomalous surface geostrophic velocity were used to study the temporal evolution of the AE. The vertical structure of the AE along 18°N in August 2012 showed a trough located near 117.5°E. The AE extended vertically downward and its distinct feature was identifiable to 200 m depth. Seasonal variations of SLA indicate that the AE lasted for 5 months (June to early November), going through the growth and nearly stationary period from mid-June to late August and then propagating westward along 18°N with varying phase speeds and shapes to the continental slope off the southeastern Hainan Island during late September to November. Furthermore, T-S characteristics suggest that the AE was generated off the western Luzon. Interannual variations of the summer (July-September) SLA presented by Empirical Orthogonal Function analysis, indicates that the local circulation was enhanced by the anomalous anticyclonic eddy along 18°N in the years of 2008, 2010, 2012 and 2013 during the period from1993 to 2014.

  14. On M2 tidal amplitude enhancement in the Taiwan Strait and its asymmetry in the cross-strait direction

    Science.gov (United States)

    Yu, Haiqing; Yu, Huaming; Ding, Yang; Wang, Lu; Kuang, Liang

    2015-10-01

    Enhanced M2 tidal amplitude in the Taiwan Strait (TS) and asymmetric M2 tidal amplitude in the cross-strait direction have been found and reproduced in numerical simulations. In this study, Finite Volume Coastal Ocean Model (FVCOM) is applied to investigate the mechanisms behind these features. Model results show that the linear interaction of waves from the East China Sea (ECS) and the Luzon Strait (LS) can explain the formation of the co-amplitude and co-phase lines of the M2 tide in the nodal point area, while the waves from the ECS dominate the tidal motion in the TS according to a basic linear wave superposition. Model simulation also show that wave reflection and transition occur when the M2 tidal waves from the ECS propagate through the TS and encounter an sharply deepened topography. The interaction of these induced reflection waves and the incident waves from the ECS is the main cause for the enhanced M2 tidal amplitude in the TS. The distribution of the sharply deepened topography, rather than the Coriolis effect, is the main reason for the asymmetry of the M2 tidal amplitude in the cross-strait direction in the TS. These findings provide some references for tidal dynamics in other areas, especially where long waves propagate through the shallow water to the deep sea.

  15. Vegetation types on Mount Akiki, Northern Luzon, Philippines

    NARCIS (Netherlands)

    Bout, I.E.

    2002-01-01

    Mount Akiki (16° 37’ N, 120° 53’ E, c. 2760 m alt.) is one of the highest mountain peaks in the Cordillera mountain range, Luzon Island, Philippines. It is situated in the municipality of Benguet, north-east of Baguio City (a world famous tourist city in the region) and is north-west of Mt Pulog, Lu

  16. Nepenthes ultra (Nepenthaceae), a new species from Luzon, Philippines

    NARCIS (Netherlands)

    Cheek, M.; Jebb, M.

    2013-01-01

    Nepenthes ultra is described from low altitude, ultramafic coastal scrub in Luzon, Philippines. It is placed in the Nepenthes alata group and is assessed as Endangered using the IUCN 2001 standard. Open cast mining and touristic development are threats to this species.

  17. Internal Gravity Waves in the Strait of Luzon: Dispersion Studies Using Fourier and Continuous Wavelet Transforms

    Science.gov (United States)

    2009-10-09

    are compared to results from Korteweg D’Vries theory. Good agreement is obtained for dispersion estimates using wavelet analysis and those from KdV ...analysis and those from KdV theory. 1 Background Internal waves (IWs) occur throughout the world’s oceans and seas. Well known examples in- clude IWs...recognize that KdV theory describes a two-layer model and the IWs under Understanding the Earth as a Complex System 235 investigation occur in a

  18. Moored Observations of Internal Waves in Luzon Strait: 3-D Structure, Dissipation, and Evolution

    Science.gov (United States)

    2016-03-01

    dramatically over the 50 day observation period, much more so than accounted for by the barotropic forcing. Hypotheses for this variability include 1...only) projects. Launch and recovery positions are indicated by the triangles and circles, respectively. Figure 10: Top left: Phase

  19. 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

  20. Study on the Tidal Wave System and Formation Mechanism of M2 Tide in the Taiwan Strait

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wei-sheng; SONG Zhi-yao; ZHANG Jin-shan; ZHANG Hong-gui; KONG Jun; WANG Yan-hong

    2008-01-01

    To study the Taiwan Strait (TS), an unusual sea area, the numerical model in marginal seas of China is used to simulate and analyze the tidal wave motion in the strait. The numerical modeling experiments reproduce the amphidromic system of the M2 tide in the south end of the Taiwan strait, and consequently confirm the existence of the degenerate amphidromic system. On this basis, further discussion is conducted on the M2 system and its formation mechanism. It can be concluded that the tidal waves of the TS is consisted of the progressing wave from the north entrance and the degenerate amphidromic system from the south entrance, in which the progressing wave from the north entrance dominates the tidal wave motion in the strait. Except for the convergent effect caused by the landform and boundary, the degenerate amphidromic system produced in the south of the strait is another important factor for the following phenomena: the large tidal range in the middle of the strait, the concentrative zone of co-amplitude and co-phase line in the south of the strait. The degenerate amphidromic system is mainly produced by the incident Pacific Ocean tidal wave from the Luzon strait and the action by the shoreline and landform. The position of the amphidromic point is compelled to move toward southwest until degenerating by the powerful progressing wave from the north entrance.

  1. Climate cycles and dissolved oxygen variability off eastern Luzon, Philippines

    Science.gov (United States)

    Escobar, M.; San Diego-McGlone, M.; Jacinto, G.; Siringan, F.; Villanoy, C.; Gordon, A. L.

    2013-12-01

    We assess the effect of El Niño Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO) on the variability of dissolved oxygen off eastern Luzon, Philippines. In this area, bifurcation of the North Equatorial Current (NEC) into the Kuroshio and Mindanao Currents occurs. Hydrographic parameters and sediment cores obtained during the oceanographic cruises in 2011 and 2012, and data from the World Ocean Atlas 2009 (WOA09) were used in the study. Variability in dissolved oxygen (DO) concentration was observed from surface to the thermocline between the neutral (2011) and La Niña (2012) phase. Based on optimum multiparameter analysis, there was a change in the fraction of water masses in the area. Under neutral conditions, waters off eastern Luzon consist mainly of water (NPSW) from the Kuroshio recirculation gyre that contain higher DO. In contrast, during La Niña conditions the North Equatorial Current becomes stronger bringing in water (NPTW) with lower DO. Thus, variability in DO off eastern Luzon is influenced by the change in the source of the water mass arising from the shift in bifurcation latitude that is linked to ENSO. Longer-term variability in DO was examined using a 2.15m sediment core taken in the shelf off eastern Luzon. The sediment record was used to reconstruct the depositional redox environment in the last 1000 years. The elements V, Ni, Cr, Mn and Fe were normalized to Ti and used as chemical proxies to track DO variability. Results show that DO fluctuations have occurred in the past, and these changes are in agreement with DO variability driven by the Pacific Decadal Oscillation.

  2. Leptospira-rat-human relationship in Luzon, Philippines.

    Science.gov (United States)

    Villanueva, Sharon Yvette Angelina M; Saito, Mitsumasa; Baterna, Rubelia A; Estrada, Crystal Amiel M; Rivera, Ana Kriselda B; Dato, Micaella C; Zamora, Pia Regina Fatima C; Segawa, Takaya; Cavinta, Lolita L; Fukui, Takashi; Masuzawa, Toshiyuki; Yanagihara, Yasutake; Gloriani, Nina G; Yoshida, Shin-ichi

    2014-11-01

    Leptospirosis is a zoonotic infection that is caused by the pathogenic species of Leptospira. Rats are the most important reservoirs of these organisms. Our study aimed to characterize Leptospira isolates from humans and rats and elucidate the Leptospira-rat-human relationship in Luzon, Philippines. Forty strains were isolated from humans and rats. The isolates were confirmed to be Leptospira and pathogenic through rrl- and flaB-PCR, respectively. Around 73% of the isolates were found to be lethal to hamsters. Serotyping showed that there were mainly three predominant leptospiral serogroups in the study areas namely Pyrogenes, Bataviae, and Grippotyphosa. Gyrase B gene sequence analysis showed that all the isolates belonged to Leptospira interrogans. Most had 100% similarity with serovar Manilae (15/40), serovar Losbanos (8/40), and serogroup Grippotyphosa (8/40). Strains from each group had highly identical pulsed-field gel electrophoresis patterns and were further grouped as A (Pyrogenes, 14), B (Bataviae, 8), and C (Grippotyphosa, 10). Results further revealed that similar serotypes were isolated from both humans and rats in the same areas. It is suggested that these three predominant groups with highly similar intra-group PFGE patterns may have been primarily transmitted by rats and persistently caused leptospirosis in humans particularly in the Luzon islands.

  3. Strike up Student Interest through Song: Technology and Westward Expansion

    Science.gov (United States)

    Steele, Meg

    2014-01-01

    Sheet music, song lyrics, and audio recordings may not be the first primary sources that come to mind when considering ways to teach about changes brought about by technology during westward expansion, but these sources engage students in thought provoking ways. In this article the author presents a 1917 photograph of Mountain Chief, of the Piegan…

  4. Students' misconceptions about U.S. westward migration.

    Science.gov (United States)

    Ferretti, Ralph P; MacArthur, Charles A; Okolo, Cynthia M

    2007-01-01

    Fifth-grade students with learning disabilities (LD) and their typically achieving (TA) peers participated in an 8-week investigation about 19th-century U.S. westward migration. During their investigations, the students analyzed primary and secondary sources to understand the experiences of these emigrants and Native peoples. The analysis of source material was preceded by teacher-led discussions about the possibility of bias in evidence that affects the trustworthiness of historical documentation. Quantitative analyses showed that these investigations were associated with gains in students' knowledge about the period of westward expansion and a better understanding of historical content and historical inquiry; however, these gains were not always comparable for students with LD and their TA peers. Furthermore, misconceptions about this historical period and the processes of historical investigation were evident in students' responses before and after instruction. We discuss how design features of the instruction and its implementation may have contributed to the development and persistence of these misconceptions.

  5. Un-optimistic Prospects for the Westward Movement of Aluminium

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    <正>The westward movement of aluminium is essential for the industrial development.Up till now,the northwestern area has planned to construct more than 40 aluminium projects with a total production capacity of over 20 million tons.The future rate of progress of newly constructed projects are directly related to the supplies of the aluminium market,having critical guiding meaning for the trends of

  6. IMF BY dependence of the extent of substorm westward electrojet

    Indian Academy of Sciences (India)

    T Arun; Ajay Dhar; K Emperumal; B M Pathan

    2005-04-01

    In this paper the duskward extension of the westward auroral electrojet is investigated for substorm intervals on the basis of magnetograms recorded at the Indian Antarctic station, Maitri. The database comprises three years from 1998-2000. Based on an initial study of the magnetograms, an arbitrary local time of 2030 MLT is fixed to define the early manifestation of the substorm westward electrojet. Using this criterion 12 substorms are identified and the possible causes examined. Many of these events are observed to be associated with a moderate to intense ring current.The hourly average of the GSM BY-component of the interplanetary magnetic field (IMF) for the hour preceding the substorm onset at Maitri is negative for most of the events. It is suggested that the azimuthal shift of the auroral electrojets in the southern hemisphere resulting from a negative BY-component of the IMF influences the extent of the substorm westward electrojet. This finding implies that the IMF may have a role in controlling the longitudinal extent of substorm occurrence.

  7. Auroral radio absorption and the westward travelling surge

    Energy Technology Data Exchange (ETDEWEB)

    Collis, P.N.; Korth, A.

    1983-11-01

    Measurements from a network of riometers during the passage of an auroral westward traveling surge are presented. These show that the energetic precipitation producing the radio absorption expands in an almost identical fashion to the softer precipitation associated with the visible surge; but it is delayed by about two minutes with respect to the surge. The delay is interpreted as a hardening of the precipitating electron spectrum as the surge goes by. Simultaneous observations of electrons at synchronous orbit are shown to support this conclusion. 24 references.

  8. Paleoproductivity during the Younger Dryas off northeastern Luzon, Philippines

    Science.gov (United States)

    Quevedo, J. M. D.; Siringan, F. P.; Villanoy, C.

    2014-12-01

    The influence of the Younger Dryas (YD) event on primary production off the northeast shelf of Luzon, Philippines is examined using sediment cores from two deep sea sites north of the Bicol shelf and with varying relative influence from terrestrial sediment input and the Kuroshio Current. Core A is immediately west of the Kuroshio feeder current and is off the slope while Core B is from a bathymetric high located almost west of Core A. XRF-, CHN- and LOI-derived geochemical proxies are utilized for reconstruction. A decrease in sediment input from ~12.9 to ~11.6 kyr BP corresponding to the YD event is indicated by the proxies, Ti, Al, and Al/Ti, in both cores. This is consistent with the drier climate during this period. Primary productivity indicators in the cores show opposing trends during the YD; Core A shows an increasing trend while Core B shows a decreasing trend. The decreasing trend in Core B can be due to a decrease in terrestrial nutrient input due to a decrease in precipitation. On the other hand, the increasing trend in Core A can be due to a swifter Kuroshio Current caused by a swifter and more southerly NEC bifurcation which in turn is due to a southerly shift of the ITCZ during YD. A swifter Kuroshio would have enhanced upwelling induced by steeper sea surface across the current and by more intense cyclonic gyres due to flow separation where the shelf width suddenly decreases north of the Bicol Shelf.

  9. The Davis Strait

    DEFF Research Database (Denmark)

    The Bureau of Minerals and Petroleum (BMP) is planning for further exclusive licences for exploration and exploitation of hydrocarbons in the Greenland off shore areas of Davis Strait. To support the decision process BMP has asked DCE - Danish Centre for Environment and Energy and the Greenland...... with the existing licence blocks, the SEIA describes the physical and biological environment including protected areas and threatened species, contaminent levels, and natural resource use. This description of the existing situation then forms the basis for assessment of the potential impacts of oil activities...

  10. SAPS onset timing during substorms and the westward traveling surge

    Science.gov (United States)

    Mishin, Evgeny, V.

    2016-07-01

    We present multispacecraft observations in the magnetosphere and conjugate ionosphere of the onset time of subauroral polarization streams (SAPS) and tens of keV ring current injections on the duskside in three individual substorms. This is probably the first unequivocal determination of the substorm SAPS onset timing. The time lag between the SAPS and substorm onsets is much shorter than the gradient-curvature drift time of ˜10 keV ions in the plasmasphere. It seemingly depends on the propagation time of substorm-injected plasma from the dipolarization onset region to the plasmasphere, as well as on the SAPS position. These observations suggest that fast onset SAPS and ring current injections are causally related to the two-loop system of the westward traveling surge.

  11. Westward propagating twin gyres in the equatorial Indian Ocean

    Science.gov (United States)

    Reddy, P. Rahul Chand; Salvekar, P. S.; Deo, A. A.; Ganer, D. W.

    2004-01-01

    A reduced-gravity (1$\\frac{1}{2-layer) model forced by daily climatological winds simulates twin, anticyclonic gyres, which propagate westward on either side of the equator. The gyres form at the beginning of both the Southwest Monsoon and the Northeast monsoon in the equatorial eastern Indian Ocean, and subsequently propagate across the basin. Their existence is supported by velocity observations taken during WOCE in 1995 and by TOPEX/Poseidon sea-level observations during 1993. They are also present in the ECCO model/data product. They form at the front of a Rossby-wave packet generated by the reflection of the equatorial jet (EJ) from the eastern boundary of the basin. They are likely either Rossby solitons or result from the nonlinear interaction between the EJ and the Rossby-wave front.

  12. Tidal propagation and dissipation in the Taiwan Strait

    Science.gov (United States)

    Yu, Haiqing; Yu, Huaming; Wang, Lu; Kuang, Liang; Wang, Hui; Ding, Yang; Ito, Shin-ichi; Lawen, Johannes

    2017-03-01

    Previous research on tides and tidal dynamics in the Taiwan Strait (TS) is reviewed in this paper. Tidal dynamics, which is the basic and dominant hydrodynamics in this area, attracts much interest in the last 30 years and till now its physical mechanism is still in debate. In this study, the major research methods and findings of previous works on barotropic tides in the TS are summarized. Based on Finite Volume Coastal Ocean Model (FVCOM), the main tidal constituents (M2, S2, K1, O1) are well simulated with the mean root-mean-square (RMS) errors of 4.7, 2.0, 1.3 and 0.7 cm between the observed and simulated tidal constants, respectively. It has been proved that semi-diurnal tidal movement is mainly determined by the waves from the East China Sea (ECS), while waves from the ECS and the Luzon Strait (LS) play comparable roles in diurnal tidal movement in the TS by linear superposition and the interaction of these two waves is the main cause for the progressive diurnal tidal waves in the TS. Furthermore, energy analysis revealed that the M2 tidal wave system in the TS and its adjacent area south to the shoal is an standing wave system and the anti-node appears in the central TS while the wave node locates in the shoal area, which can be contributed to the interaction of the incident waves from the ECS and the topography step south to Taiwan island, while the shoal also has an impact on the whole semi-diurnal tidal wave system in the TS. This standing wave system is consistent with the little energy dissipation in the central TS and much energy dissipation in the southern TS, where the shallow water effect also contributes to the local dissipation to some extent.

  13. amphibians and reptiles of luzon island, philippines, Ⅵ:the herpetofauna of the subic bay area

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    we present detailed species accounts for 55 species of amphibians and reptiles (14 species of frogs,24 snakes,16 lizards,one turtle) from 24 localities in the vicinity of subic bay,southern zambales province,luzon island,philippines.although we note numerous species that are conspicuously absent in subic bay (and which we expect will eventually be recorded in the region),our many new records plus a summary of the available historical museum specimen data depict a diverse subset of species diversity known from the southern zambales mountains of southwestern luzon.we compare our data to several other recent herpetofunal surveys from luzon,discuss biogeographic regionalism of this complex island,and report on numerous new natural history observations for many included species.with the absence of any protected areas in the entire province,the amphibians and reptiles of zambales should be a particularly important future conservation priority.

  14. The Davis Strait

    DEFF Research Database (Denmark)

    The Bureau of Minerals and Petroleum (BMP) is planning for further exclusive licences for exploration and exploitation of hydrocarbons in the Greenland off shore areas of Davis Strait. To support the decision process BMP has asked DCE - Danish Centre for Environment and Energy and the Greenland...... with the existing licence blocks, the SEIA describes the physical and biological environment including protected areas and threatened species, contaminent levels, and natural resource use. This description of the existing situation then forms the basis for assessment of the potential impacts of oil activities....... If more licences are granted in the assessment area implementation of an environmental background study programme is planned to fi ll the data gaps that have been identifi ed and provide information required to support the environmental planning and regulation of the oil activities. The new information...

  15. Chromite deposits of the north-central Zambales Range, Luzon, Philippines

    Science.gov (United States)

    Rossman, D.L.

    1970-01-01

    Peridotite and gabbro form an intrusive complex which is exposed over an area about 35 km wide and 150 km long in the center of the Zambales Range of western Luzon. The Zambales Complex is remarkable for its total known resources, mined and still remaining, of about 15 million metric tons of chromite ore. Twenty percent of Free World production was obtained from this area between 1950 and the end of 1964; in 1960 production reached a high of 606,103 metric tons of refractory-grade ore, mostly from the Coto mine near Masinloc, and 128,426 metric tons of metallurgical ore from the Acoje mine. The United States imports 80 to 90 percent of its refractory-grade chromite from the Philippines, and its basic refractory technology has been designed upon the chemical and physical characteristics of Coto high-alumina chromite ore. Continuation of this pattern will depend upon discovery of additional ore reserves to replace those depleted by mining. The Zambales Ultramafic Complex is of the alpine type in which lenticular or podiform deposits of chromite lie in peridotite or dunite, mostly near Contacts with gabbroic rocks. Layered structures, foliation, and lineation commonly are well developed and transect boundaries between major rock units, including chromite deposits, at any angle. Accordingly, these structures cannot be used as guides in exploration and mining as they are used in stratiform complexes such as the Bushveld, where chromite layers extend for many miles. Probably 90 percent of the known deposits in the Zambales Complex are located in two belts in its northern part. One zone containing high-aluminua refractory-grade deposits extends northeast from the Coto mine and Chromite Reservation No. I along a peridotite contact with olivine gabbro, and another of high-chromium metallurgical grade chromite extends south through the Zambales and Acoje properties, and swings westward around the south side of Mount Lanai along a peridotite contact with norite. The textures

  16. On two species of Archipelothelphusa Bott, 1969 (Crustacea: Decapoda: Brachyura: Sundathelphusidae) from Luzon, Philippines

    NARCIS (Netherlands)

    Ng, P.K.L.

    1991-01-01

    The taxonomic problems concerning freshwater crabs of the genus Archipelothelphusa Bott, 1969 (Gecarcinucoidea: Sundathelphusidae) are discussed. The identity of Para-Bary-thelphusa grapsoides subsp. longipes Balss, 1937, is clarified, and a new species, A. celer spec. nov. is described from Luzon,

  17. Taiwan strait dispute

    Directory of Open Access Journals (Sweden)

    Kastrati Bilbil

    2015-12-01

    Full Text Available The end of the Cold War resulted in a diffusion of the level of threat worldwide and concluded the system of bipolarity in the world. Beside the European continent, where the rivalries were at the highest level, the consequences of the end of the Cold War were especially visible in North-East Asia. A decrease of military activities of Russia and China, and the retreat of the USA from the region, give way for improvement of political and economical relations between the countries of the region. The end of hostilities produced by the Cold War no doubt have relaxed relations between countries in the region and opened ways for a new more peaceful co-existence. However, this does not mean that the region is not vulnerable to some of the hot spots such as North Korea, Spratly Parcels and especially Taiwan Strait. The latter is considered to be the most dangerous potential Asian zone of crisis in the twenty-first century.

  18. Coral-based Holocene sea level of Paraoir, western Luzon, Philippines

    Science.gov (United States)

    Siringan, Fernando P.; Shen, Chuan-Chou; Lin, Ke; Abigania, Maria Isabel T.; Gong, Shou-Yeh

    2016-06-01

    Shallow-water corals are crucial natural archives for reconstructing deglacial sea-level changes. However, significant discrepancies exist between sea-level records from different places. Here we present recently acquired 230Th-dated coral ages between 10,256 ± 50 yr BP and 6654 ± 29 yr BP (before 1950 AD) from Paraoir, western Luzon, Philippines to document deglacial sea-level rise of the western Pacific. The results indicate that the Paraoir reef started growing 10.3 kyr BP from about 29 m below present sea level, and reached 8 m below the PSL at 7.2 kyr BP. The Paraoir sea-level records are consistent with those of northwestern Luzon and the western Australia coast; both of which are coral-based records in continental or island arc settings. But sea levels of Luzon are significantly higher than those of Tahiti, a basaltic island on oceanic crust. We propose that the differences in sea level between the Philippine and Tahiti result from spatial variations of glacial isostatic adjustment of the two sites.

  19. 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.

  20. Mediterranean waters along and across the Strait of Gibraltar, characterization and zonal modification

    Science.gov (United States)

    Naranjo, Cristina; Sammartino, Simone; García-Lafuente, Jesús; Bellanco, María J.; Taupier-Letage, Isabelle

    2015-11-01

    Hydrological data collected in the Strait of Gibraltar have been used to examine the distribution and spatial-temporal evolution of the water masses in the area. The spatial variability has been addressed by means of a clustering method that determines the affinity of a collection of temperature-salinity samples to one of the water masses involved in the exchange. The method, which has been applied to a nearly-synoptic data set, highlights the clear evolution of the Mediterranean Waters as they flow westward through the Strait. While up to four different Mediterranean Waters are spatially distinguishable east of the main sill of Camarinal in the Strait, most of their differentiating characteristics are eroded after flowing over this restrictive topography due to mixing. West of the sill, therefore, speaking of a unique Mediterranean Water seems more appropriate. The same applies to the North Atlantic Central Water flowing in the opposite direction, which is noticeably modified along its path to the Mediterranean Sea, most of its transformation taking place in the Camarinal sill surroundings. A series of repeated transects carried out in the eastern and western sides of the Strait, provided a temporal analysis of the water masses evolution: the temporal variability manifests seasonality in the surface waters, while interannual signal is mainly detected in the deeper water masses. It is worth remarking the statistically significant positive trend of Western Mediterranean Deep Water (0.009 °C/year) and Winter Intermediate Water (0.03 °C/year), with the latter showing also intermittent occurrence in the Strait.

  1. Quantifying submarine landslide processes driven by active tectonic forcing: Cook Strait submarine canyon, New Zealand.

    Science.gov (United States)

    Mountjoy, J. J.; Barnes, P. M.; Pettinga, J. R.

    2006-12-01

    The Cook Strait submarine canyon system is a multi-branched, deeply incised and highly sinuous feature of New Zealand's active margin, covering some 1500km2 of sea floor between the North and South Islands and spanning water depths of between 50 and 2700m. The canyon occurs at the transition from the westward dipping oblique subduction zone adjacent to the SE North Island and the zone of continental transpression in NE South Island. The recent acquisition of high resolution (5-10m) SIMRAD EM300 bathymetric data allows active tectonic and geomorphic processes to be assessed and quantified at a level of detail previously not possible. While multiple active submarine fault traces have been identified in the Cook Strait by previous studies, quantitative information on their activity has been limited. Cook Strait is structurally characterized by westward dipping thrust faults and E-W trending dextral strike slip faults. The multiple large magnitude high frequency earthquake sources define zones of very high ground shaking expected to contribute to triggering of extensive submarine slope failures. Landslide activity within the canyon system is widespread and represents the dominant mass movement process affecting canyon heads and walls, redistributing material into valley fills. Complexes of large (km3) multi-stepped, deep-seated (100m) translational bedding plane failures represented by gently sloping (<3°) evacuated slide-scar areas with associated blocky valley fill deposits are numerous. Steep catchment heads, channel walls and the leading edges of asymmetric thrust-fault driven anticlines are dominated by gulley and rill systems with associated eroded and/or incipient slump features. Large (107m3+) slide blocks are recognized in discrete failures with quantifiable displacement vectors. Tsunamigenic landslides in this environment are inevitable. This study will provide quantification of landslide models including triggering mechanisms, discrete geometries and

  2. Stratigraphic units overlying the Zambales Ophiolite Complex (ZOC) in Luzon, (Philippines): Tectonostratigraphic significance and regional implications

    Science.gov (United States)

    Queaño, Karlo L.; Dimalanta, Carla B.; Yumul, Graciano P.; Marquez, Edanjarlo J.; Faustino-Eslava, Decibel V.; Suzuki, Shigeyuki; Ishida, Keisuke

    2017-07-01

    The Zambales Ophiolite Complex (ZOC) on the island of Luzon, Philippines is one of the most well-studied crust-mantle sequences in the region. Several massifs comprise the ZOC, one of which is the Coto Block overlain by clastic sedimentary units previously dated as Eocene. Geochronologic studies from diabase, granodiorites and other late-stage magmatic products similarly yielded the same age. Succeeding tectonic models have therefore all been grounded on the assumption that the entire ZOC is Eocene. Recent investigations, however, revealed the presence of chert blocks within the Early to Middle Miocene clastic formation overlying the Acoje Block in the northern part of the ophiolite complex. Radiolarians extracted from the cherts yielded a stratigraphic range that suggests a Late Jurassic to Early Cretaceous age. The recognition of a much older age than previously reported of the ZOC warrants a re-examination of its actual distribution and genesis. Correlating with other similarly-aged ophiolites, we suggest defining a western Mesozoic ophiolite belt, largely extending from the west-central portion of the archipelago to the northeastern tip of Luzon island. Tentatively, we attribute the Mesozoic ophiolitic and associated rocks in western Luzon to an arc-continent collision involving the Philippine Mobile Belt and the Palawan Microcontinental Block. In addition, differences in the clastic compositions of the Cenozoic sedimentary formations provide material not only for deciphering the ZOC's unroofing history but also for constraining the timing of province linkage. The intermittent appearance of lithic fragments and detrital minerals from the ophiolite in the units of the Middle Miocene Candelaria Limestone and the Late Miocene to Early Pliocene Sta. Cruz Formation indicates significant but geographically variable contributions from the ophiolite complex. In the northern Zambales Range, the Sta. Cruz Formation caps the Coto Block and the Acoje Block of the ZOC

  3. FEEDING ECOLOGY OF TREE-CLIMBING MANGROVE SESARMID CRABS FROM LUZON, PHILIPPINES

    Directory of Open Access Journals (Sweden)

    JIMMY TEVAR MASAGCA

    2009-01-01

    Full Text Available Despite the large ecological study of tree-climbing mangrove sesarmid crabs in other countries, the Philippine representatives appear to have not been investigated extensively. This paper presents the feeding ecology as to dependence on mangrove trees of sesarmids in different mangrove areas of southern Luzon. This is biased on the nature of the crab habitats, arboreal climbing skills and burrowing behavior of the sesarmids: Selatium elongatum and Episesarma versicolor − exclusive mangrove tree climbers (EMTC; Sarmatium germaini − occasional mangrove tree climber (OMTC; and the non-mangrove tree-climbing (NMTC sesarmids- Neosarmatium smithii, Perisesarma bidens and Perisesarma eumolpe

  4. Cretaceous to Recent extension in the Bering Strait region, Alaska

    Science.gov (United States)

    Dumitru, Trevor A.; Miller, Elizabeth L.; O'Sullivan, Paul B.; Amato, Jeffrey M.; Hannula, Kimberly A.; Calvert, Andrew T.; Gans, Phillip B.

    1995-06-01

    completed by the Late Cretaceous and thus that the present-day thinner crust of the Bering Strait region developed primarily in the Cretaceous. Regional tilting and at least several more kilometers of local erosion followed in Eocene-early Oligocene time as documented by fission-track ages from deeper levels of the crustal section exposed in the Kigluaik Mountains. This event is generally coeval with development of the offshore transtensional Hope and Norton Basins which flank the Seward Peninsula to the north and south. Modern seismicity, active normal faults, and basin-range topography document Pliocene(?) to Recent north-south extension across the region. Fission-track data indicate that exhumation during this period was quite limited, less than 2-3 km. This inferred history of protracted extension in the Bering Strait region stands in sharp contrast to well-documented Cretaceous and Tertiary north-south shortening in interior Alaska. This contrast in tectonic histories suggests a model in which contraction and westward extrusion of crustal fragments from interior Alaska by strike-slip faulting were accommodated by north-south extension in the Bering Strait region. This resulted in the counterclockwise rotation of extruded crustal blocks, the extensional thinning of the western part of the Brooks Range crustal root, and the formation of transtensional basins and unusually broad continental shelves between Alaska and Russia.

  5. Development of the Philippine Mobile Belt in northern Luzon from Eocene to Pliocene

    Science.gov (United States)

    Suzuki, Shigeyuki; Peña, Rolando E.; Tam, Tomas A.; Yumul, Graciano P.; Dimalanta, Carla B.; Usui, Mayumi; Ishida, Keisuke

    2017-07-01

    The origin of the Philippine Archipelago is characterized by the combination of the oceanic Philippine Mobile Belt (PMB) and the Palawan Continental Block (PCB). This paper is focused on the geologic evolution of the PMB in northern Luzon from Eocene to Pliocene. The study areas (northern Luzon) are situated in the central part of the PMB which is occupied by its typical components made up of a pre-Paleocene ophiolitic complex, Eocene successions, Eocene to Oligocene igneous complex and late Oligocene to Pliocene successions. Facies analysis of the middle Eocene and late Oligocene to early Pliocene successions was carried out to understand the depositional environment of their basins. Modal sandstone compositions, which reflect the basement geology of the source area, were analyzed. Major element geochemistry of sediments was considered to reconstruct the tectonic settings. The following brief history of the PMB is deduced. During the middle Eocene, the PMB was covered by mafic volcanic rocks and was a primitive island arc. In late Eocene to late Oligocene time, the intermediate igneous complex was added to the mafic PMB crust. By late Oligocene to early Miocene time, the PMB had evolved into a volcanic island arc setting. Contributions from alkalic rocks are detected from the rock fragments in the sandstones and chemical composition of the Zigzag Formation. During the middle Miocene to Pliocene, the tectonic setting of the PMB remained as a mafic volcanic island arc.

  6. Indonesian Maritime Security Cooperation In the Malacca Straits

    Science.gov (United States)

    2015-06-01

    Straits compared to other littoral states since the majority of Indonesia’s trade is conducted through the Lombok and the Sunda Straits. He argues...Weight Tonnage (DWT) should not be allowed to pass through the Malacca Straits and should be re-routed through the Lombok -Makassar Straits.107

  7. Deep Mediterranean Water footprint measured in the Strait of Gibraltar during the last decade.

    Science.gov (United States)

    Naranjo Rosa, Cristina; García Lafuente, Jesús; Sammartino, Simone; Sánchez Garrido, José Carlos

    2016-04-01

    Deep Mediterranean Water is formed during winter in the Mediterranean Sea due to atmospheric cooling of salty Mediterranean waters. When it reaches the Strait of Gibraltar it finally flows westward into the Atlantic, from where it begins to descend the continental slope by gravity while it mixes with the overlying waters and becomes lighter. Far beyond the strait itself it maintains a recognizable signal and so affects the thermohaline circulation of the Atlantic Ocean. Thus, the Strait of Gibraltar is the perfect site to monitor the interannual changes occurring over the whole Mediterranean Sea just before Mediterranean Waters incorporate to the Atlantic circulation. From October 2004 until today the Temperature and Salinity of the Mediterranean outflow through the Strait of Gibraltar have been monitored, resulting in a long-term temporal series with more than 11 years of measurements. A Conductivity-Temperature sensor is placed around 12 meters above the seafloor in the Espartel Sill (35°56'N 5°45'W), the last constriction the Mediterranean deep water finds before leaving the Mediterranean, and is configured to take measurements every 30 minutes. The instrument has been collecting data almost continuously from 2004, except for a 2.5 month gap in 2009 and a 5 months gap during 2011. This record allows the study of the long-term trend and the interannual changes occurring over the whole Mediterranean during the last 11 years. First results show a mean temperature of the deep Mediterranean waters of 13.20±0.06 °C and a mean salinity of 38.39±0.02. It is noteworthy the cold signals registered in 2006 and 2013, which could be the result of the severe winters of 2005 and 2012 in Europe, and the positive trend in 2015 toward warmer values. No significant trends have been found for the whole period. On the other hand, the time series exhibits a noticeable interannual variability that merits a deeper analysis.

  8. Model simulations of early westward flow across the Tasman Gateway during the early Eocene

    NARCIS (Netherlands)

    Sijp, Willem P.; von der Heydt, A.S.|info:eu-repo/dai/nl/245567526; Bijl, P.K.|info:eu-repo/dai/nl/314028110

    2016-01-01

    The timing and role in ocean circulation and climate of the opening of Southern Ocean gateways is as yet elusive. Recent micropalaeontological studies suggest the onset of westward throughflow of surface waters from the SW Pacific into the Australo-Antarctic Gulf through a southern shallow opening o

  9. Latitude-dependence and dispersion of the westward drift in the geomagnetic field

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The main geomagnetic field models of IGRF1900---2000 are used to study the latitude-dependence of the westward drift in the main field. The results show that the latitude-dependence exists in the magnetic components with different wavelengths (m=l-10). The globai-average westward drift rate of the component of m=l is 0.189°/a with the maximum of 0.295°/a at latitudes 40°-45°. The component of m=2 has an average drift rate of 0.411°/a with the maximum of 1.305°/a at latitude -60°. As for the components with further shorter wavelengths, the drift is generally restricted in a limited latitude range, and has many smaller drift rates. This latitude-dependence of westward drift can not be explained by rigid rotation of the earth's core. The results of this note also show that there is a negative dispersion in the westward drift, namely the components of long wavelengths drift faster than those of short wavelengths.This dispersion feature is not in agreement with Hide's MHD model. It is likely needed to find a new mechanism for explaining the observed feature of dispersion.

  10. A MILESTONE IN CROSS-STRAITS RELATIONS

    Institute of Scientific and Technical Information of China (English)

    DENG YUNGUANG; DING XING

    2010-01-01

    @@ Chongqing, the southwestern municipality that served as China's capital during World War Ⅱ, will be remembered again for hosting a landmark event in the Chinese history on June 29. On that day, Chen Yunlin,President of the mainland's Association for Relations Across the Taiwan Straits,and Chiang Pin-kung, Chairman of Taiwan's Straits Exchange Foundation,signed the long-awaited Economic Cooperation Framework Agreement (ECFA) in Chongqing, a move hailed by many as a milestone in cross-Straits relations.

  11. On Flow Variability in the Bosphorus Strait

    Science.gov (United States)

    2011-08-27

    Atlantic Treaty Organization (NATO) Undersea Research Center ( NURC ) in collaboration with the Turkish Navy Office of Navigation, Hydrography, and...Oceanography deployed two mooring sections in the Bosphorus Strait (at the Black Sea and Sea of Marmara entrances) from the R/V Alliance (a NATO- NURC ...research vessel) as a part of TSS08 ( NURC project) and "Exchange Processes in Ocean Straits" (EPOS, NRL project) programs in September 2008 (Figure 1

  12. Intraspecific rearrangement of duplicated mitochondrial control regions in the Luzon Tarictic Hornbill Penelopides manillae (Aves: Bucerotidae).

    Science.gov (United States)

    Sammler, Svenja; Ketmaier, Valerio; Havenstein, Katja; Tiedemann, Ralph

    2013-12-01

    Philippine hornbills of the genera Aceros and Penelopides (Bucerotidae) are known to possess a large tandemly duplicated fragment in their mitochondrial genome, whose paralogous parts largely evolve in concert. In the present study, we surveyed the two distinguishable duplicated control regions in several individuals of the Luzon Tarictic Hornbill Penelopides manillae, compare their characteristics within and across individuals, and report on an intraspecific mitochondrial gene rearrangement found in one single specimen, i.e., an interchange between the two control regions. To our knowledge, this is the first observation of two distinct mitochondrial genome rearrangements within a bird species. We briefly discuss a possible evolutionary mechanism responsible for this pattern, and highlight potential implications for the application of control region sequences as a marker in population genetics and phylogeography.

  13. Predisposition Factors of Students’ Choice in Agriculture, Fisheries and Natural Resources (AFNR Courses (Luzon Area

    Directory of Open Access Journals (Sweden)

    DR. ROMEO C. CLEMENTE

    2014-02-01

    Full Text Available This study is an inquiry into the motivational, personality, and extrinsic variables as factors affecting students’ predisposition in their career choice for agriculture, fisheries and forestry. It features empirical facts generally reflective of the recent conditions of public and private Higher Education Institutions (as NUCAFs, PIAs and PIFs identified by NAFES-CHED and DA of Luzon, Philippines vis-à-vis problems and reasons of continuous decline in the subscription of Filipino students for AFNR courses. Subsumed in the notable findings for Luzon area (i.e., most enrollees and their parents are marginalized; most mothers who are mere housekeepers heavily influence children’s disposition; most professional AFNR parents and enrollees’ siblings who are now AFNR professionals poorly influence them to take the same course; scholarship grants or free tuition fee as a prime way out to finish college education; personal ideal expectation of students for the government to provide promising local employment; common social motive to participate in addressing problems on food security for the continuously increasing population; economic motive to shorter waiting time for employment; SUCs feel obliged to expand curriculum offering to non-AFNR courses to survive institutional fiscal constraints; dearth of educationally qualified faculty and administrators; campaign for the AFNR curriculum programs as effective strategy to improve enrolment rate; low passing rate in AFNR board examinations due to low participation rate, expensive requirements of review, generic contents of examination, and deficiency on the quality and quantity of facilities/equipment and library holdings in most AFNR State Colleges/Universities served as framework of reference for the formulation of proposed education policy reforms/measures and advocacy interventions designed to spur interest in AFNR courses.

  14. Electromagnetically driven westward drift and inner-core superrotation in Earth’s core

    Science.gov (United States)

    Livermore, Philip W.; Hollerbach, Rainer; Jackson, Andrew

    2013-01-01

    A 3D numerical model of the earth’s core with a viscosity two orders of magnitude lower than the state of the art suggests a link between the observed westward drift of the magnetic field and superrotation of the inner core. In our model, the axial electromagnetic torque has a dominant influence only at the surface and in the deepest reaches of the core, where it respectively drives a broad westward flow rising to an axisymmetric equatorial jet and imparts an eastward-directed torque on the solid inner core. Subtle changes in the structure of the internal magnetic field may alter not just the magnitude but the direction of these torques. This not only suggests that the quasi-oscillatory nature of inner-core superrotation [Tkalčić H, Young M, Bodin T, Ngo S, Sambridge M (2013) The shuffling rotation of the earth’s inner core revealed by earthquake doublets. Nat Geosci 6:497–502.] may be driven by decadal changes in the magnetic field, but further that historical periods in which the field exhibited eastward drift were contemporaneous with a westward inner-core rotation. The model further indicates a strong internal shear layer on the tangent cylinder that may be a source of torsional waves inside the core. PMID:24043841

  15. Electromagnetically driven westward drift and inner-core superrotation in Earth's core.

    Science.gov (United States)

    Livermore, Philip W; Hollerbach, Rainer; Jackson, Andrew

    2013-10-01

    A 3D numerical model of the earth's core with a viscosity two orders of magnitude lower than the state of the art suggests a link between the observed westward drift of the magnetic field and superrotation of the inner core. In our model, the axial electromagnetic torque has a dominant influence only at the surface and in the deepest reaches of the core, where it respectively drives a broad westward flow rising to an axisymmetric equatorial jet and imparts an eastward-directed torque on the solid inner core. Subtle changes in the structure of the internal magnetic field may alter not just the magnitude but the direction of these torques. This not only suggests that the quasi-oscillatory nature of inner-core superrotation [Tkalčić H, Young M, Bodin T, Ngo S, Sambridge M (2013) The shuffling rotation of the earth's inner core revealed by earthquake doublets. Nat Geosci 6:497-502.] may be driven by decadal changes in the magnetic field, but further that historical periods in which the field exhibited eastward drift were contemporaneous with a westward inner-core rotation. The model further indicates a strong internal shear layer on the tangent cylinder that may be a source of torsional waves inside the core.

  16. Closing the Mass Budget between Bering Strait and the Arctic Basin: The Chukchi Slope Current

    Science.gov (United States)

    Corlett, W. B.; Pickart, R. S.

    2016-02-01

    After passing through Bering Strait, Pacific-origin water flows across the Chukchi Sea in different branches that ultimately exit the shelf and provide heat, freshwater, and nutrients to the interior basin. It is important, therefore, to understand where and by what mechanisms the water is fluxed offshore. We have compiled all known shipboard hydrographic sections occupied across the Chukchi shelfbreak and slope that include direct velocity measurements (shipboard ADCP or lowered ADCP). In all, there are 46 sections occupied during the months of May-October from 2002 to 2014, spanning the region from Barrow Canyon to approximately 168°W. The data reveal the presence of a surface-intensified, westward-flowing current over the continental slope, situated offshore of the eastward-flowing shelfbreak jet. We call this feature the Chukchi slope current, which exists under all wind conditions. Using these data plus previously published transport values in Bering Strait and the Beaufort shelfbreak jet, we attempt to close the mass budget of the Chukchi shelf. The mean heat transport of the Chukchi slope current during the summer months is estimated, which has the potential to melt a substantial amount of pack-ice in the Canada Basin and influence the geographical distribution of the ice melt.

  17. Timing of Surface-Rupturing Earthquakes on the Philippine Fault Zone in Central Luzon Island, Philippines

    Science.gov (United States)

    Tsutsumi, H.; Daligdig, J. A.; Goto, H.; Tungol, N. M.; Kondo, H.; Nakata, T.; Okuno, M.; Sugito, N.

    2006-12-01

    The Philippine fault zone is an arc-parallel left-lateral strike-slip fault zone related to oblique subduction of the Philippine Sea plate beneath the Philippine island arc. The fault zone extends for about 1300 km from the Luzon Island southward to the Mindanao Island. This fault zone has been seismically active with more than 10 earthquakes greater than M7 in the last century. The July 16, 1990, Luzon earthquake was the largest event that produced 120-km-long surface rupture along the Digdig fault. The coseismic displacement was predominantly left-lateral strike-slip with maximum slip of about 6 m. The Philippine fault zone in the Luzon Island consists of four left-stepping en echelon faults: the San Manuel, San Jose, Digdig, and Gabaldon faults from north to south. Historical documents and geomorphic data suggest that the San Manuel and Gabaldon faults ruptured most recently during historical earthquakes in 1796 and 1645, respectively. However, paleoseismic activities and slip rates for these faults were poorly constrained. In order to reconstruct chronology of surface-rupturing earthquakes, we excavated multiple trenches across these faults in the past three years. We have excavated two sites, San Gregorio and Puncan sites, across the Digdig fault. At the both sites, we identified near vertical fault zones that contain evidence for four surface-rupturing earthquakes during the past 2000 years, including the 1990 rupture. The timing of the penultimate earthquake is constrained to prior to 1400 AD, suggesting that the Digdig fault did not rupture during the 1645 earthquake. The average recurrence interval of the Digdig fault is about 600 years. A left-lateral slip rate of 8-13 mm/yr was obtained for the Digdig fault based on stream offsets and age of alluvial fan at San Juan in the central portion of the fault. For the San Jose fault, we excavated two trenches north of downtown San Jose. The sediments exposed on the trench walls were warped into a monocline by

  18. Isotopic and geochemical signatures of Late Quaternary sediments in the Fram Strait area

    Science.gov (United States)

    Maccali, J.; Hillaire-Marcel, C.; Carignan, J.; Reisberg, L. C.

    2010-12-01

    Arctic freshwater/sea-ice export through Fram Strait contributes to the Atlantic Meridional Overturning Circulation (AMOC) and acts as a trigger or feedback mechanism in the climate/ocean system. Here, geochemical and isotopic analyses of cores raised along a transect through the Strait are used to document changes in sediment sources and sea-ice transport since the LGM. Radiogenic isotope and elemental data in leachable fractions vs residues are used as proxies for water mass vs sediment source signatures, respectively. Unequivocal linkage between leachates and water-mass properties are illustrated by the anthropogenic-lead overprint in leachates from core-top sediments. Below this polluted layer, leachates and residues from late Holocene sediments carry distinct geochemical signatures E and W of the Strait. Eastward, below the North Atlantic Water (NAW) mass flowing northward, Th/Zr and Th/Pb concentration ratios ranging 0.040-0.041 and 0.85-0.90, respectively, label GIN seas and western Spitzbergen sediment-sources. Westward, below outflowing Arctic waters and sea-ice routes, these ratios range 0.032-0.035 and 0.72-0.75, respectively, and label NE Greenland and Arctic sediment sources. Pb-isotopes exhibit a similar pattern with sediment carrying a mixed Variscan-Pan-African signature below the NAW route, and a mixture of less radiogenic sources in sediments deposited below the outflowing Arctic waters and sea-ice route. Back in time, divergent trends in some radiogenic isotope values are recorded westward, below the outflowing Arctic waters and sea-ice route. Whereas isotopic properties of residues suggest sedimentary supplies originating from the Canadian Arctic and/or the NW Greenland margin, lead data from leachates bear an "Arctic Ocean" signature illustrating variable relative contributions from the Russian vs Canadian ice-margins and/or rivers. During deglacial times, a significant change in sedimentary supplies is recorded at ~ 14 ka along with some

  19. Westward migration of oceanic ridges and related asymmetric upper mantle differentiation

    Science.gov (United States)

    Chalot-Prat, Françoise; Doglioni, Carlo; Falloon, Trevor

    2017-01-01

    Combining geophysical, petrological and structural data on oceanic mantle lithosphere, underlying asthenosphere and oceanic basalts, an alternative oceanic plate spreading model is proposed in the framework of the westward migration of oceanic spreading ridges relative to the underlying asthenosphere. This model suggests that evolution of both the composition and internal structure of oceanic plates and underlying upper mantle strongly depends at all scales on plate kinematics. We show that the asymmetric features of lithospheric plates and underlying upper asthenosphere on both sides of oceanic spreading ridges, as shown by geophysical data (seismic velocities, density, thickness, and plate geometry), reflect somewhat different mantle compositions, themselves related to various mantle differentiation processes (incipient to high partial melting degree, percolation/reaction and refertilization) at different depths (down to 300 km) below and laterally to the ridge axis. The fundamental difference between western and eastern plates is linked to the westward ridge migration inducing continuing mantle refertilization of the western plate by percolation-reaction with ascending melts, whereas the eastern plate preserves a barely refertilized harzburgitic residue. Plate thickness on both sides of the ridge is controlled both by cooling of the asthenospheric residue and by the instability of pargasitic amphibole producing a sharp depression in the mantle solidus as it changes from vapour-undersaturated to vapour-saturated conditions, its intersection with the geotherm at 90 km, and incipient melt production right underneath the lithosphere-asthenosphere boundary (LAB). Thus the intersection of the geotherm with the vapour-saturated lherzolite solidus explains the existence of a low-velocity zone (LVZ). As oceanic lithosphere is moving westward relative to asthenospheric mantle, this partially molten upper asthenosphere facilitates the decoupling between lower asthenosphere

  20. Observational evidence for westward propagation of temperature inversions in the southeastern Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Shankar, D; Gopalakrishna, V.V.; Shenoi, S.S.C.; Durand, F; Shetye, S.R.; Rajan, C.K.; Johnson, Z.; Araligidad, N.; Michael, G.S.

    -1 GEOPHYSICAL RESEARCH LETTERS, VOL. ???, XXXX, DOI:10.1029/, Observational evidence for westward propagation of temperature inversions in the southeastern Arabian Sea D. Shankar,1 V. V. Gopalakrishna,1 S. S. C. Shenoi,1 F. Durand,1 S. R. Shetye,1 C. K. Rajan,2.... Ocean. Syst., 4, 1?29, 1996. Brandt, P., L. Stramma, F. Schott, J. Fischer, M. Dengler, and D. Quad- fasel, Annual Rossby waves in the Arabian Sea from TOPEX/Poseidon altimeter and in situ data, Deep-Sea Res. II, 49, 1197?1210, 2002. Bruce, J. G., D. R...

  1. Tectonic evolution of Bransfield Strait, West Antarctica

    Science.gov (United States)

    Barker, Daniel Hugh Njal

    Bransfield Strait is a young (Rocas Verdes basin supports the contention that Bransfield Strait rifting is in a transitional stage between continental/arc rifting and organized sea-floor spreading, and that it is a useful modern analog for the Rocas Verdes basin. Furthermore, it suggests that detachment faulting may be a common feature of backarc basins. Recognition of low-angle detachment faulting and simple-shear extension is essential for estimating basin extension, and the amount of crustal shortening and thickening that may occur during inversion of a basin such as the Rocas Verdes basin.

  2. Inner Core Rotation from Geomagnetic Westward Drift and a Stationary Spherical Vortex in Earth's Core

    Science.gov (United States)

    Voorhies, C. V.

    1999-01-01

    The idea that geomagnetic westward drift indicates convective leveling of the planetary momentum gradient within Earth's core is pursued in search of a differentially rotating mean state, upon which various oscillations and secular effects might be superimposed. The desired state conforms to roughly spherical boundary conditions, minimizes dissipative interference with convective cooling in the bulk of the core, yet may aide core cooling by depositing heat in the uppermost core and lower mantle. The variational calculus of stationary dissipation applied to a spherical vortex within the core yields an interesting differential rotation profile akin to spherical Couette flow bounded by thin Hartmann layers. Four boundary conditions are required. To concentrate shear induced dissipation near the core-mantle boundary, these are taken to be: (i) no-slip at the core-mantle interface; (ii) geomagnetically estimated bulk westward flow at the base of the core-mantle boundary layer; (iii) no-slip at the inner-outer core interface; and, to describe magnetic locking of the inner core to the deep outer core, (iv) hydrodynamically stress-free at the inner-outer core boundary. By boldly assuming the axial core angular momentum anomaly to be zero, the super-rotation of the inner core is calculated to be at most 1.5 degrees per year.

  3. Batek: Traditional Tattoos and Identities in Contemporary Kalinga, North Luzon Philippines

    Directory of Open Access Journals (Sweden)

    Analyn Ikin V. Salvador-Amores

    2002-06-01

    Full Text Available In the early 16th century, traditional tattooing is widespread in the Philippines, but very little is known or written about the practice. Sources for the study of traditional tattoos in Northern Luzon are very inadequate and merely make vague statements on the function and symbolic meaning of tattoos, as well as the relationship between the practice and culture as a whole. The statements likewise reveal a distinctly ethnocentric deportment. Until today, tattooing and tattoo designs in the Cordilleras are best understood within the context of headhunting. Headhunting was the only known reason for tattooing, and, to this day, no one knows exactly what tattoos signify. This paper provides insights into the roles and functions of the tattoos, and how the tattoos (batek become cultural symbols of the intricate rituals brought about by community regimens of the Ilubo, Kalinga. No longer practiced, the batek of the Ilubo is a visually powerful rendering of symmetry and unity of designs. Batek now serve as an archive of culture for the group.

  4. Indigenous Knowledge and Sustainable Pest Management in Rice Farming Communities of southeastern Luzon, Philippines

    Directory of Open Access Journals (Sweden)

    Amelia R. Nicolas

    2015-01-01

    Full Text Available The paper presents the traditional pest management systems in the rice-growing areas of the southeastern part of Luzon, Philippines, particularly in the province of Camarines Sur. These systems have been proven to be productive, sustainable, ecologically sound, and attuned to the social, economic, and cultural features of the food-poor small farmers in the said province. The various indigenous pest control strategies were recorded and classified into cultural, physical, biological, mechanical, and chemical. A mixture of qualitative techniques such as interview guides and Focus Group Discussions were used in the survey. Results indicate that, despite the increasing modernization and commercialization of agriculture, the great majority of respondents who are peasants or marginal farmers still strongly embrace and patronize the use of Indigenous Knowledge (IK that they have inherited from their ancestors many decades ago. IK on pest management have helped them control and sustainably manage pest problems and meet their subsistence needs without depending on costly energy-based inputs. IK should therefore be recorded and used to devise innovative research for agricultural researchers, extension workers, development practitioners, and environmentalists for sustainable pest management before this wealth of practical knowledge is lost forever since most of the indigenous management techniques for rice pest control are rapidly disappearing as affected by major social, economic, and political pressures.

  5. An ethnomycological survey of macrofungi utilized by Aeta communities in Central Luzon, Philippines

    Directory of Open Access Journals (Sweden)

    De Leon AM

    2012-04-01

    Full Text Available Questionnaires and formatted interviews were used to determine mushrooms used as food and as materials for societal rituals and beliefs among six Aeta communities in three provinces of Central Luzon, Northern Philippines. Thirty-eight different fungi were utilized by the Aeta communities: 21 in Pampanga, 10 in Tarlac, and 19 in Zambales. Fourteen fungal species were collected and identified based on their morphological characters: Auricularia auricula, A. polytricha, Calvatia sp., Ganoderma lucidum, Lentinus tigrinus, L. sajor-caju, Mycena sp., Pleurotus sp., Schizophyllum commune, Termitomyces clypeatus, T. robustus, Termitomyces sp. 1, Termitomyces sp. 2, and Volvariella volvacea. Twelve of the identified macrofungi were consumed as food while Ganoderma lucidum and Mycena sp. were used as house decoration and medicine, respectively. The Aeta communities also performed rituals prior to the collection of these mushrooms, including tribal dancing, praying and kissing the ground. Their indigenous beliefs regarding mushrooms are also documented. This is the most extensive enthnomycological study on the Aeta communities in the Philippines.

  6. OCCURRENCE AND DISTRIBUTIONAL RANGE OF MANGROVE VASCULAR FLORA OF CATANDUANES ISLAND, LUZON, PHILIPPINES

    Directory of Open Access Journals (Sweden)

    JIMMY TEVAR MASAGCA

    2008-01-01

    Full Text Available Mangroves play very significant roles not only on the economic aspects but also on the ecological aspects as biobelting for tidal surges and tsunamis. The loss of human lives due to the deadly tsunamis in East Asia and the unabated destruction of coastal vegetation have resulted in a renewed focus on the mangrove resources. The purpose of this paper is to report the existing mangrove database of the typhoon-prone island province of Catanduanes in Luzon, Philippines which will be used as bases in determining the appropriate educational management initiatives of various sectors for mangrove rehabilitation and regeneration. A total of 37 species of mangrove vascular flora (13 species of major mangrove elements, 10 species of minor mangrove elements and 14 associated mangrove species were identified in the island under study. Two species of the genus Avicennia ( A. marina and A. officinalis were noted in the island. The other genera ( Bruguiera , Ceriops , Sonneratia and Rhizophora are well distributed in the designated eco-zones. Nypa fruticans is the most important mangrove plant species and a member of the screwpine family (Pandanaceae, Pandanus tectorius which is an associated mangrove species is well-distributed all throughout the island.

  7. Evidence for Active Westward Tilting of Fortymile Wash, Nye County, Nevada

    Science.gov (United States)

    McKague, H. L.; Sims, D. W.; Waiting, D. J.

    2006-12-01

    Fortymile Wash is located east and south of a potential high-level nuclear waste repository at Yucca Mountain, Nevada. Several lines of evidence suggest that this may be an area of active westward tilting associated with the continued development of Crater Flat basin and slip on the Bare Mountain normal fault. Near the southern end of Busted Butte, the incised channel of Fortymile Wash changes trend downgradient from south to south-southwest. Further southward, the incised main channel grades to a divergent distributary channel system that shows evidence of increasingly westward tilt. Viewed in profiles oriented normal to the incised channel and across the Fortymile Wash distributary system, topographic elevation of the western margin of the fan decreases southward, resulting in the elevation of the western margin of Fortymile Basin being as much as 18 m [59 ft] lower than the channel system on the eastern fan margin. Mapping of the surficial deposits within the distributary channel system (Pelletier, et al., 2005; Geophy. Res. Ltr., Vol. 32) may be interpreted to show a westward shift (downslope) of the locus of erosional activity toward the topographically lower western fan margin. Most of the older alluvium (Qa3 {86±40-16 ka}) has been eroded from the eastern portion, while incipient incision into the older alluvium is occurring on the western side of the distributary channel system. The results from level-line benchmark surveys (Gilmore, 1992; USGS OFR 92- 450) from 1915 and 1984 show gradual and systematic elevation changes east of the Bare Mountain fault to just east of Amargosa City, Nevada, where a step-like increase occurs. The level-line surveys are near and along the path of U.S. Highway 95, which traverses the distributary channel system of the Fortymile Wash alluvial fan in the southern portion of the Fortymile Wash basin. These lines of evidence indicate disequilibrium in the channel system that would result from active westward tilting of the

  8. Observed Volume Fluxes in the Bosphorus Strait

    Science.gov (United States)

    2011-01-01

    Tugrul et al, 2002]. [4] The United States Naval Research Laboratory (NRL) and the NATO Undersea Research Center ( NURC ) in col- laboration with the...Turkish Navy Office of Navigation, Hydrography and Oceanography deployed two mooring sections in the Bosphorus Strait as a part of the TSS08 ( NURC

  9. Bottom fauna of the Malacca Strait

    Digital Repository Service at National Institute of Oceanography (India)

    Parulekar, A.H.; Ansari, Z.A.

    Bottom fauna of Malacca Strait (connecting the Indian Ocean with Pacific) in the depth range of 80 to 1350 m, is dominated by meiofauna which exceeds macrofauna by 12.5 times in weight and by more than 780 times in population density. Standing crop...

  10. Gliders in the Fram Strait Observatory

    Science.gov (United States)

    Beszczynska-Möller, Agnieszka; Fahrbach, Eberhard; Schauer, Ursula; Rohr, Harald; Lee, Craig

    2013-04-01

    Variability of oceanic advective fluxes through Fram Strait, one of the main gateways to the Arctic Ocean, has been monitored since 1997 by the array of 16 moorings and summer hydrographic sections. The main focus is on the inflow of warm Atlantic waters from the Nordic Seas, the only source of heat for the Arctic Ocean, and on the freshwater outflow to the North Atlantic. However, spatial resolution of the moored array, which varies from 10 to 30 km, is not sufficient to resolve the mesoscale variability of the complex, topographically flow through the strait. In the recently established multidisciplinary Fram Strait Observatory a combination of oceanographic observations by moorings and gliders with acoustic tomography measurements and the eddy-resolving numerical model will provide a new tool to assess the contribution of mesoscale dynamics to the variability of oceanic fluxes through Fram Strait. Since 2007, in the framework of the EU DAMOCLES and ACOBAR projects, the long-term moored observations in Fram Strait have been complemented with repeated glider sections. During eight summer and autumn missions the oceanographic data with high spatial resolution were collected down to 1000 m by Seagliders profiling along the moored array. Here we report on the results from five years of gliders measurements and a comparison of glider data to observations from moorings and ship-borne CTD sections. The special attention is paid to measurements in the West Spitsbergen Current, where gliders have to operate in the strong current regime (occasional events up to 1 m/s). Spatially averaged glider data were also applied in the finite element inverse model FEMSECT and preliminary results are presented. Future plans envisage a substitution of the upper part of moored array with repeated glider sections to achieve year-round glider operations in the partially sea-ice covered region. Since 2010 the array of RAFOS sources and tomographic sources providing RAFOS signal with

  11. Contraction of westward-travelling nonlocal modons due to the vorticity filament emission

    Directory of Open Access Journals (Sweden)

    D. Berson

    2002-01-01

    Full Text Available Long-term evolution of westward-travelling non-local modons on the β-plane, i.e. dipolar vortices imbedded in slowly damping Rossby wave fields, is studied numerically. In the framework of the nondivergent (barotropic model, two stages of the evolution are observed. At the first stage (for about 30 synoptic periods, the parameters and the form of the vortex practically remain constant, whereas at the second stage, vorticity filaments are emitted. Due to the filamentation, the vortex core contracts, the potential vorticity peaks of the vortex pair get closer, and the modon speeds up. In the divergent (equivalent-barotropic model, nonlocal modons and the Lamb modon (that has no wave field outside the dipolar core evolve much more slowly, essentially preserving the initial shape and propagation speed until about 100 synoptic periods.

  12. Wind-driven coastal upwelling and westward circulation in the Yucatan shelf

    Science.gov (United States)

    Ruiz-Castillo, Eugenio; Gomez-Valdes, Jose; Sheinbaum, Julio; Rioja-Nieto, Rodolfo

    2016-04-01

    The wind-driven circulation and wind-induced coastal upwelling in a large shelf sea with a zonally oriented coast are examined. The Yucatan shelf is located to the north of the Yucatan peninsula in the eastern Gulf of Mexico. This area is a tropical shallow body of water with a smooth sloping bottom and is one of the largest shelves in the world. This study describes the wind-driven circulation and wind-induced coastal upwelling in the Yucatan shelf, which is forced by easterly winds throughout the year. Data obtained from hydrographic surveys, acoustic current profilers and environmental satellites are used in the analysis. Hydrographic data was analyzed and geostrophic currents were calculated in each survey. In addition an analytical model was applied to reproduce the currents. The results of a general circulation model were used with an empirical orthogonal function analysis to study the variability of the currents. The study area is divided in two regions: from the 40 m to the 200 m isobaths (outer shelf) and from the coast to the 40 m isobath (inner shelf). At the outer shelf, observations revealed upwelling events throughout the year, and a westward current with velocities of approximately 0.2 m s-1 was calculated from the numerical model output and hydrographic data. In addition, the theory developed by Pedlosky (2007) for a stratified fluid along a sloping bottom adequately explains the current's primary characteristics. The momentum of the current comes from the wind, and the stratification is an important factor in its dynamics. At the inner shelf, observations and numerical model output show a wind-driven westward current with maximum velocities of 0.20 m s-1. The momentum balance in this region is between local acceleration and friction. A cold-water band is developed during the period of maximum upwelling.

  13. KARYOMORPHOLOGY OF TH E PHILIPPINE ROCK GOBY, Glossogobius giuris (GOBIIDAE FROM LAKE TAAL AND SOME RIVERS OF CAVITE, LUZON ISLAND

    Directory of Open Access Journals (Sweden)

    JOSE A. ORDONEZ

    2003-01-01

    Full Text Available The karyomorphology of Glossogobius giuris (Gobiidae obtained from Lake Taal and some rivers of Cavite in Luzon Island, Philippines was described. Metaphase chromosome analysis (colchicine-sodium citrate-Carnoy's fixation-Giemsa staining procedures of the hematopoitetic cells in the anterior kidneys revealed that the diploid chromosome number was 2n=46 (46A. Fundamental Number (FN is also 46, since all chromosomal morphology were acrocentrics without any distinguishable heteromorphic pair of chromosomes in the metaphase spreads from both dry and wet preparations. This study confirms previous reports on the chromosomal sets of G. giuris from India.

  14. THE STATUS OF MOLLUSK DIVERSITY AND PHYSICAL SETTING OF THE MANGROVE ZONES IN CATANDUANES ISLAND, LUZON, PHILIPPINES

    Directory of Open Access Journals (Sweden)

    JIMMY T. MASAGCA

    2010-09-01

    Full Text Available The status of mollusk diversity and physical setting of mangrove areas in Catanduanes island, Luzon (Philippines are described. A total of 57 species of mollusks, consisting of 27 gastropods and 30 bivalves were recorded in the island. Registering higher values of species diversity indices (Margalef and species richness (Menhinick are the prosobranch, Terebralia sulcata; corbiculid bivalve, Geloina coaxans; potamidiids, Cerithidea cingulata and Cerithidea rhizophorarum; and two other species of the genus Littorina (Littorinopsis. Using the physiographic model, majority of the mangrove areas under study follow the composite river and wave-dominated setting with some few areas having the wave-dominated, tide-dominated allochthonous setting.

  15. Knowledge hubs along the straits of Malacca

    OpenAIRE

    Evers, Hans-Dieter; Hornidge, Anna-Katharina

    2007-01-01

    World history has known areas of relative isolation and areas of high intensity of cultural interaction. The Mediterranean Sea, the Silk Road or the Straits of Malacca can be cited as such crucial contact zones. Within these areas, centres sprung up that served as interfaces between cultures and societies. These “hubs” as we would like to call them, emerged at various points throughout the contact zones, rose to prominence and submerged into oblivion due to a variety of natural calamities or ...

  16. Nearshore bedform instability in the eastern entrance to the Qiongzhou Strait,South China Sea

    Institute of Scientific and Technical Information of China (English)

    Heqin CHENG; Jiufa LI; Daowei YIN; Maotian LI; Baocan WANG

    2008-01-01

    Six bathymetric transect profiles were drawn from the nautical charts of 1942,1962 and 1992 to show that the nearshore seabed remained unstable during the recent 50 Vears in the middie channel of the eastern entrance to the Oiongzhou Strait,South China Sea.Our results dem onstrate that the multi-year averaged seabed aggradational rate was 25 cm/a and erosion rate was 12.5 cm/a.Lateral migration rate of the sea bedform identified from the his torical contours was about 100 m/a in the SE direction. Bedform measurements were made using GPY Shallow Seismic Profiler in 1994 in the study area.The records revealed four types of distinctive bedforins that were com.Posed of fine and medium sands.The average spacing of large and small-scale sand dunes is 416 m and 144 m and the average height remains 8.8 m and 4.9 m.The spatial and temporal equilibrium-range spectra of numerical bedform records were applied to estimate short term celerity of bed form movement.Results indicate that large and small dunes migrated at an average celerity of 0.02 cm/hr eastward and 0.09 cm/hr westward in the calm sea weather,while their celerity can reach 53 cm/hr eastward during typhoon season and iS only 0.008 cm/hr westward when NNE winds prevail.The results also show that the larger the temporal and spa tial scale is.the smaller the bedform movement celerity appears.On the other hand,the smaller-scale bedform celerity of the present study is much greater than that of flume,empirical and theoretical data,but close to the wind tunnel and field-measured data of similar grain size.

  17. Nearshore bedform instability in the eastern entrance to the Qiongzhou Strait,South China Sea

    Institute of Scientific and Technical Information of China (English)

    Barendra PURKAIT; Amitava MUKHERJEE

    2008-01-01

    Six bathymetric transect profiles were drawn from the nautical charts of 1942,1962 and 1992 to show that the nearshore seabed remained unstable during the recent 50 Vears in the middie channel of the eastern entrance to the Oiongzhou Strait,South China Sea.Our results dem onstrate that the multi-year averaged seabed aggradational rate was 25 cm/a and erosion rate was 12.5 cm/a.Lateral migration rate of the sea bedform identified from the his torical contours was about 100 m/a in the SE direction. Bedform measurements were made using GPY Shallow Seismic Profiler in 1994 in the study area.The records revealed four types of distinctive bedforins that were com. Posed of fine and medium sands.The average spacing of large and small-scale sand dunes is 416 m and 144 m and the average height remains 8.8 m and 4.9 m.The spatial and temporal equilibrium-range spectra of numerical bedform records were applied to estimate short term celerity of bed form movement.Results indicate that large and small dunes migrated at an average celerity of 0.02 cm/hr eastward and 0.09 cm/hr westward in the calm sea weather,while their celerity can reach 53 cm/hr eastward during typhoon season and iS only 0.008 cm/hr westward when NNE winds prevail. The results also show that the larger the temporal and spa tial scale is.the smaller the bedform movement celerity appears.On the other hand,the smaller-scale bedform celer ity of the present study is much greater than that of flume, empirical and theoretical data,but close to the wind tunnel and field-measured data of similar grain size.

  18. On the dynamics of strait flows: an ocean model study of the Aleutian passages and the Bering Strait

    Science.gov (United States)

    Ezer, Tal; Oey, Lie-Yauw

    2013-03-01

    A high-resolution numerical ocean circulation model of the Bering Sea (BS) is used to study the natural variability of the BS straits. Three distinct categories of strait dynamics have been identified: (1) Shallow passages such as the Bering Strait and the Unimak Passage have northward, near barotropic flow with periodic pulses of larger transports; (2) wide passages such as Near Straits, Amukta Pass, and Buldir Pass have complex flow patterns driven by the passage of mesoscale eddies across the strait; and (3) deep passages such as Amchitka Pass and Kamchatka Strait have persistent deep return flows opposite in direction to major surface currents; the deep flows persist independent of the local wind. Empirical orthogonal function analyses reveal the spatial structure and the temporal variability of strait flows and demonstrate how mesoscale variations in the Aleutian passages influence the Bering Strait flow toward the Arctic Ocean. The study suggests a general relation between the barotropic and baroclinic Rossby radii of deformations in each strait, and the level of flow variability through the strait, independent of geographical location. The mesoscale variability in the BS seems to originate from two different sources: a remote origin from variability in the Alaskan Stream that enters the BS through the Aleutian passages and a local origin from the interaction of currents with the Bowers Ridge in the Aleutian Basin. Comparisons between the flow in the Aleutian passages and flow in other straits, such as the Yucatan Channel and the Faroe Bank Channel, suggest some universal topographically induced dynamics in strait flows.

  19. Gravity is indeed the driving force for fault pattern formation and westward displacement of the lithosphere

    CERN Document Server

    Papa, A R R

    2005-01-01

    Gravity influence of the Sun and the Moon on the Earth is the cause of the fault pattern on Earth's surface we observe nowadays and also of the westward displacement of the lithosphere. A somewhat related hypotheses advanced in the past have been that tidal torque of the Moon may be significant. However, it has been argued that it is untenable essentially on the grounds that the viscosity of the Earth's mantle is far too high in comparison with the forces involved. To state this it was assumed that the Earth's relevant characteristic is that of two spherical shells separated by a viscous liquid, the external shell rotating at a constant angular velocity with respect to the inner shell. Here I show that this picture is not quite right and that a more careful look leads us to one in which both shells rotates at different mean angular velocities and with a forward-backward sequence of movements relative to each other. In this way what was supposed to be the principal factor against gravity influence becomes the ...

  20. Offshore finfish mariculture in the Strait of Juan de Fuca

    Energy Technology Data Exchange (ETDEWEB)

    Rensel, Jack; Kiefer, Dale; Forster, John R.; Woodruff, Dana L.; Evans, Nathan R.

    2007-10-07

    Finfish mariculture has existed in the U.S. Pacific Northwest for over thirty years, but for the past 15 years most effort has focused on culture of Atlantic salmon in protected, inshore cage sites. The Strait of Juan de Fuca (the "Strait") is a large area with relatively sparce shoreline development and several apparent advantages for mariculture using offshore technology.

  1. 33 CFR 80.1385 - Strait of Juan de Fuca.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Strait of Juan de Fuca. 80.1385 Section 80.1385 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Thirteenth District § 80.1385 Strait of Juan de Fuca. The 72 COLREGS shall apply on all waters of...

  2. Assessment Of Trophic Status In Bali Strait

    Directory of Open Access Journals (Sweden)

    Umi Zakiyah

    2016-04-01

    Full Text Available The nutrient content in Banyuwangi coastal environment mostly caused by human activities along the coastal area of Bali strait especially in Banyuwangi surrounding areas. The change of organic element content in waters will directly affect plankton community structure and the aquatic trophic level. The aimed of this research were to analyze the plankton community structure, and to observe the quality of aquatic and determine Bali Strait especially Banyuwangi coastal area trophic level. This research was done in October 2015 at Banyuwangi coastal area. Methods used in this research was descriptive with seawater sampling for water quality analysis of several parameter such as nitrates (NO3, phosphates (PO4, TOM (Total Organic Matter and Chlorophyll-a, meanwhile other parameters were, temperature, pH, Dissolved Oxygen dan salinity from three different depth of three different stations, coastal area of Bangsring, Tandjung Wangi and Muncar. The results for water quality parameters showed that Bangsring coastal area was the most  healthy waters compared to Bangsring and Muncar. Meanwhile, there were tendency that the concentration mostly high in the surface and decrease along with the deeper depth. This condition presumed caused by the ARLINDO current that passed through Bali strait. Phytoplankton identified and calculated consisted of 3 division, namely Chlorophyta, Chrysophyta, and Cyanophyta with total density ranges between 4-2888 ind/ml. The value of diversity index phytoplankton (H’ ranges between 0,3-0,7. Based on the result it can be concluded that Banyuwangi coastal areas were at throphic level of  oligotrophic tended to mesotrophic in northern part and eutrophic especially in Muncar. Thus, it was suggested for the Government to prevent this area becoming more polluted in the future.

  3. Morphology, seismic characteristics and development of the sediment dispersal system along the Taiwan-Luzon convergent margin

    Science.gov (United States)

    Hsiung, Kan-Hsi; Su, Chih-Chieh; Yu, Ho-Shing; Chang, Jih-Hsin

    2015-12-01

    The sediment dispersal system along the convergent margin between Taiwan and Luzon links the terrestrial and shallow marine sediments from the source areas nearby Taiwan orogen to the ultimate sink in the northern Manila Trench. Using seismic reflection profiles and bathymetry mapping we determine three distinct morpho-tectonic features of the Penghu Submarine Canyon, deep-sea Penghu Channel and oceanic Manila Trench which are linearly interconnected to form a longitudinal sediment route. Seismic profiles show characteristic features of truncated strata along canyon walls and cut-and-fills in canyon bottom. Deformed and uplifted bathymetric ridges and troughs and volcanic intrusions with unstratified and chaotic seismic facies are associated with the Penghu Channel. The seismic facies of the trench wedge are characterized by sub-horizontal and conformable layers of sediment stacking upwards to the trench floor. The sediment wedge adjacent to the inner lower slope is deformed to blind folds and thrust faults as precursors of the accretionary prism. The most prominent seismic characteristics is wide-spread undulating reflectors on the seafloor along the west edge of the sediment dispersal system and the toe of the South China Sea Basin floor, suggesting a large sediment wave field with a turbidity currents origin. The location, orientation and geometry of this sediment routing system are mainly controlled by underlying tectonics in progressive changes from arc-continental collision in transition to subduction. The deep-sea Penghu Channel is formed by compression in transitional zone of the North Luzon Ridge region, neither subduction nor channel erosion. The sediments in northern Manila Trench are mainly transported by turbidity currents via the upslope deep-sea Penghu Channel and Penghu Canyon and trench axis is filled up to a flat-floor trench wedge without sediment ponding. A four-stage development of sediment dispersal system in Taiwan-Luzon convergent margin

  4. Biogeochemical cycling in the Taiwan Strait

    Digital Repository Service at National Institute of Oceanography (India)

    Naik, H.; Chen, C-T.A.

    is attributed to the retreat of remnant winter water that flows northward (Chen and Sheu, 2006) and in the northern transect (NTS) to topographically driven upwelling (Hu et al., 1980). The upwelling feature in the mid-strait 3.1. Hydrography and Parsons, 1972...-distilled, Millipore water contain- ing 1% MgCO 3 and then stored at C020 C14 C for further analysis in the shore laboratory. A Turner Designs model 10-AU fluo- rometer measured Chl a after extraction with 90% acetone (Strickland and Parsons, 1972). 3. Results The data...

  5. Two new species of freshwater crabs of the genus Sundathelphusa Bott, 1969 (Decapoda: Brachyura: Gecarcinucidae) from caves in Luzon, Philippines.

    Science.gov (United States)

    Husana, Daniel Edison M; Yamamuro, Masumi; Ng, Peter K L

    2014-06-17

    Two cave species of Sundathelphusa are described from a karst area in southern Luzon, Philippines. Both species have elongated ambulatory legs but the eyes and carapace pigmentation are well developed, indicating they are not troglobites. Sundathelphusa danae sp. nov. is superficially more similar to S. longipes (Balss, 1937) than to S. holthuisi Ng, 2010, which was described from the same locality. Sundathelphusa danae sp. nov. is distinguished from its closest congeners by its strongly convex anterolateral margin, more swollen branchial regions, possession of a complete frontal median triangle, laterally inflated subbranchial region and the more slender ambulatory legs. Sundathelphusa vienae sp. nov. is unusual among Sundathelphusa species in that its carapace is more quadrate, with the slender and almost straight male first gonopod tapered and having a pointed terminal segment. 

  6. Ichthyoplankton gut analysis with relevance to prey availability in the waters of Lamon Bay, northeastern Luzon, Philippines

    Science.gov (United States)

    Bollozos, I.; Yniguez, A. T.; Palermo, J. H.; Cabrera, O. C.; Villanoy, C. L.

    2013-12-01

    The waters in the eastern part of Luzon are highly influenced by the western boundary current system of the western Pacific brought about by the bifurcation of the North Equatorial Current into the Kuroshio and Mindanao Current. Eddies are formed with varying intensities as an effect of the ENSO cycle. Three spatial zones were identified according to prominent current movements and circulations observed during the summer 2011 and 2012 oceanographic cruises. These events also affect the productivity in the surrounding waters. Plankton samples were collected to determine the relative abundances of major groups representing three trophic levels. The abundance and composition of phyto- and zooplankton major groups slightly varied among the zones. Gut analysis of fish larvae was then conducted to determine potential prey preference and linked to the phyto- and zooplankton densities.

  7. Zircon U-Pb Age Determination of Volcanic Eruptions in Lutao and Lanyu in the Northern Luzon Magmatic Arc

    Directory of Open Access Journals (Sweden)

    Wen-Yu Shao

    2014-01-01

    Full Text Available This paper reports for the first time zircon U-Pb ages of volcanic rocks and sands from Lutao and Lanyu, two islets off SE Taiwan in the north Luzon arc. The samples include (1 seven andesites from four volcanic units and three river/beach sands from Lutao and (2 five basaltic andesites from four volcanic units and two river/beach sands from Lanyu. The Lutao andesites contain abundant magmatic zircons, aging from ~1.54 to ~1.24 Ma for individual sample, which yielded an overall mean 206Pb/238U age of 1.31 ±± 0.03 Ma (n = 190, MSWD = 2.6. This is slightly older than, or broadly coincident with, a mean 206Pb/238U age of 1.23 ±± 0.03 Ma (n = 103, MSWD = 1.9 given by detrital zircons from the three sands. The Lanyu volcanics appear to have less abundant magmatic zircons, aging from ~2.72 to ~2.35 Ma for individual sample, which yielded an overall mean 206Pb/238U age of 2.61 ±± 0.13 Ma (n = 11, MSWD = 1.8. This accords with a mean 206Pb/238U age of 2.69 ±± 0.11 Ma (n = 34, MSWD = 4.7 obtained by detrital zircons from the two sands. The age data suggest that in Lutao and Lanyu the major volcanic eruptions occurred at ~1.3 and ~2.6 Ma, respectively. Moreover, volcanic samples from both islets contain various amounts of older inherited zircons, ~11% in Lutao and up to ~82% in Lanyu, which together with detrital zircons from the sands show main age peaks at ~150 Ma and ~1.9 and ~2.5 Ga, consistent with the notion for a _ continental crust involved in the genesis of the northern Luzon magmatic arc.

  8. The bottom water exchange between the Singapore Strait and the West Johor Strait

    Science.gov (United States)

    Sun, Yunfang; Eltahir, Elfatih; Malanotte-Rizzoli, Paola

    2017-08-01

    As a part of the border between Singapore and Malaysia, the West Johor Strait (WJS) suffered newly from harmful algal blooms. There is no previous study showing the source of the nutrients in the WJS. This paper is investigating the possible water exchange between the water in the WJS and the bottom water in Singapore Strait. This paper adopts a two-level nesting atmosphere-ocean coupled models to downscale the global atmosphere-ocean model into the Singapore coastal water, keeping the large-scale and long-term ocean and climate circulation signals and the advantages of the high-resolution. Based on the high-resolution ocean circulation fields, a Lagrangian particle tracking model is used to trace the Singapore Strait's bottom water movement and the water mixing in the WJS. The results showed that the numerical models well resolved the Singapore coastal water regional circulation. There is a small but significant bottom water (1.25%) transport from the Singapore Strait to the WJS, which occurs from the southwest coastline of Singapore. The bottom water in the Singapore Strait prefers to enter the WJS during the spring tide and the flood period, and stay in Johor Strait for 6.4 days. The spring tide is the first-order factor for the water vertical mixing in the WJS, the wind is also very important for the vertical mixing especially in neap tide condition. An overall very important factor is the light perturbation. With the strongest vertical mixing of nutrients and bottom sediments due to the spring tide, the latter ones may inhibit the light penetration during the spring tide and reduce the algal bloom. The light penetration otherwise is greater during the neap tide, when the winds are the most important factor and hence favor the algal bloom. With the strongest wind in February and the longest permanence time in June and the sufficient nutrient supply in February and June, the most serious algal blooms may happen in February and June in the WJS.

  9. On the current-voltage relationship in auroral breakups and westwards-travelling surges

    Directory of Open Access Journals (Sweden)

    A. Olsson

    Full Text Available Auroral precipitating electrons pass through an acceleration region before entering the atmosphere. Regardless of what produces it, a parallel electric field is assumed to cause the acceleration. It is well known that from kinetic theory an expression for the corresponding upward field-aligned current can be calculated, which under certain assumptions can be linearized to j=KV. The K constant, referred to as the Lyons-Evans-Lundin constant, depends on the source density and thermal energy of the magnetospheric electrons; it is an important parameter in magnetosphere-ionosphere coupling models. However, the K parameter is still rather unknown, and values are found in a wide range of 10–8–10–10 S m–2. In this study, we investigated how the type of auroral structure affects the K values. We look at onset and westwards-travelling surge (WTS events and make comparisons with earlier results from observations of more stable auroral arcs. A new analysis technique for studying those magnetospheric parameters using ground-based measurements is introduced. Electron density measurements are taken with the EISCAT radar, and through an inversion technique the flux-energy spectra are calculated. Source densities, thermal energies and potential drops are estimated from fittings of accelerated Maxwellian distributions. With this radar technique we have the possibility to study the changes of the mentioned parameters during the development of onsets and the passage of surges over EISCAT. The study indicates that the linearization of the full Knight formulation holds even for the very high potential drops and thermal temperatures found in the dynamic onset and WTS events. The values of K are found to be very low, around 10–11 S m–2 in onset cases as well as WTS events. The results may establish a new technique where ionospheric

  10. Depth dependence of westward-propagating North Atlantic features diagnosed from altimetry and a numerical 1/6° model

    Directory of Open Access Journals (Sweden)

    R. Tailleux

    2008-03-01

    Full Text Available A 1/6° numerical simulation is used to investigate the vertical structure of westward propagation between 1993 and 2000 in the North Atlantic ocean. The realism of the simulated westward propagating signals, interpreted principally as the signature of first-mode baroclinic Rossby waves (RW, is first assessed by comparing the simulated amplitude and zonal phase speeds of Sea Level Anomalies (SLA against TOPEX/Poseidon-ERS satellite altimeter data. Then, the (unobserved subsurface signature of RW phase speeds is investigated from model outputs by means of the Radon Transform which was specifically adapted to focus on first-mode baroclinic RW. The analysis is performed on observed and simulated SLA and along 9 simulated isopycnal displacements spanning the 0–3250 m depth range. Simulated RW phase speeds agree well with their observed counterparts at the surface, although with a slight slow bias. Below the surface, the simulated phase speeds exhibit a systematic deceleration with increasing depth, by a factor that appears to vary geographically. Thus, while the reduction factor is about 15–18% on average at 3250 m over the region considered, it appears to be much weaker (about 5–8% in the eddy-active Azores Current, where westward propagating structures might be more coherent in the vertical. In the context of linear theories, these results question the often-made normal mode assumption of many WKB-based theories that the phase speed is independent of depth. Alternatively, these results could also suggest that the vertical structure of westward propagating signals may significantly depend on their degree of nonlinearity, with the degree of vertical coherence possibly increasing with the degree of nonlinearity.

  11. 美国西进运动的经济意义%Economic Significance of American Westward Movement

    Institute of Scientific and Technical Information of China (English)

    陈雪

    2012-01-01

    The westward movement is an epoch-making event in the development of American civilization. Using the capitalist productive way, the westward movement explores the American West. Although it is accompanied by crimes against the native Indians, many of whom are killed off or driven to the western areas, the westward movement extends its far-reaching influence to the economic development It not only improves the scale and level of agriculture, provides possibilities and needs of transportation, but also brings enormous advancement to the industrial expansion, and thus lead to the bloom of American economy and the power of the United States.%美国的西进运动在美国的文明发展史上有着划时代的意义,它运用资本主义的生产方式开发了美国西部,尽管西进运动对于印第安人造成了精神上和肉体上的迫害,但是从经济意义上看,它深入到美国农业,交通运输业和工业方面,从而促进了美国经济的全面繁荣,增强了美国的经济实力.

  12. Atmospheric forcing of salinity in the overflow of Denmark Strait

    Directory of Open Access Journals (Sweden)

    J. Holfort

    2007-09-01

    Full Text Available The temporal evolution of the characteristics of Denmark Strait Overflow Water (DSOW is reconstructed using hydrographic data and compared with possible atmospheric forcing mechanisms. It is concluded that the main factor influencing the DSOW characteristics at a time scale of one to several years is the difference in mean sea level pressure across Denmark Strait or, in other words, the wind along Denmark Strait. At these time scales upstream changes in the characteristics of the different water masses involved in the formation of DSOW are only of minor importance. The main process responsible for the observed salinity changes in the DSOW is mixing in Denmark Strait. Triggered by the wind, different water masses contribute with changing amounts to the formation of DSOW, leading to the observed changes in the salinity of DSOW.

  13. Strait of Juan de Fuca 1 arc-second DEM

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 1-second Strait of Juan de Fuca Washington Elevation Grid provides bathymetric data in ASCII raster format of 1-second resolution in geographic coordinates. This...

  14. Strait of Juan de Fuca 6 arc-second DEM

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 6-second Strait of Juan de Fuca Washington Elevation Grid provides bathymetric data in ASCII raster format of 6-second resolution in geographic coordinates. This...

  15. Strait of Juan de Fuca 36 arc-second DEM

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 36-second Strait of Juan de Fuca Washington Elevation Grid provides bathymetric data in ASCII raster format of 36-second resolution in geographic coordinates....

  16. The amphibians and reptiles of Luzon Island, Philippines, VIII: the herpetofauna of Cagayan and Isabela Provinces, northern Sierra Madre Mountain Range

    OpenAIRE

    2013-01-01

    Abstract We provide the first report on the herpetological biodiversity (amphibians and reptiles) of the northern Sierra Madre Mountain Range (Cagayan and Isabela provinces), northeast Luzon Island, Philippines. New data from extensive previously unpublished surveys in the Municipalities of Gonzaga, Gattaran, Lasam, Santa Ana, and Baggao (Cagayan Province), as well as fieldwork in the Municipalities of Cabagan, San Mariano, and Palanan (Isabela Province), combined with all available historica...

  17. Westward moving dynamic substorm features observed with the IMAGE magnetometer network and other ground-based instruments

    Directory of Open Access Journals (Sweden)

    H. Lühr

    Full Text Available We present the ground signatures of dynamic substorm features with particular emphasis on the event interpretation capabilities provided by the IMAGE magnetometer network. This array covers the high latitudes from the sub-auroral to the cusp/cleft region. An isolated substorm on 11 Oct. 1993 during the late evening hours exhibited many of well-known features such as the Harang discontinuity, westward travelling surge and poleward leap, but also discrete auroral forms, known as auroral streamers, appeared propagating westward along the centre of the electrojet. Besides the magnetic field measurements, there were auroral observations and plasma flow and conductivity measurements obtained by EISCAT. The data of all three sets of instruments are consistent with the notion of upward field-aligned currents associated with the moving auroral patches. A detailed analysis of the electrodynamic parameters in the ionosphere, however, reveals that they do not agree with the expectations resulting from commonly used simplifying approximations. For example, the westward moving auroral streamers which are associated with field-aligned current filaments, are not collocated with the centres of equivalent current vortices. Furthermore, there is a clear discrepancy between the measured plasma flow direction and the obtained equivalent current direction. All this suggests that steep conductivity gradients are associated with the transient auroral forms. Also self-induction effects in the ionosphere may play a role for the orientation of the plasma flows. This study stresses the importance of multi-instrument observation for a reliable interpretation of dynamic auroral processes.

    Keywords. Ionosphere (Auroral ionosphere; Electric fields and currents; Ionosphere-magnetosphere interactions.

  18. Seasonal Variability of Transport Through Gibraltar, Sicily and Corsica Straits

    Science.gov (United States)

    Béranger, K.; Mortier, L.; Crépon, M.

    We have investigated the transport variability through three major straits of the Mediterranean Sea (Gibraltar, Sicily, Corsica) with a very high resolution model of the Mediterranean Sea. A numerical simulation of the Mediterranean circulation has been done with a 1/16o horizontal grid mesh, 43 vertical z-level model. Initial hydrological conditions were provided by the Mediterranean MODB5 climatology. The model has been run eleven years. It has been forced in a yearly perpetual mode by the daily sea surface fluxes from European Centre for Medium-range Weather Forecasts analysis during the year March 1998 - February 1999. This study has been supported by the french MERCA- TOR project and SHOM. We grateful the PAM team of CERFACS (Toulouse, France). Analysis is focused on three major straits which play an important role in control- ling the circulation through mass transport exchanges. Model results are compared to recent observations and good agreement is obtained. It demonstrates advantages to improve resolution in numerical models. Gibraltar and Sicily strait transports are largely baroclinic. The transport through the Gibraltar Strait is forced by density difference between the Atlantic Ocean and the Mediterranean Sea. Atlantic water (AW) penetrates the Mediterranean Sea while Mediterranean Outflow Water flows into the Atlantic Ocean. This transport is hy- draulically maximal, with a semi-annual signal, and its seasonal variation is weak. The Sicily Strait transport is probably first forced by the AW coming from the West rather than the density gradient between the western and eastern mediterranean seas. AW inflow (i.e. Eastern Mediterranean Overflow Water outflow) is maximum in late Fall and minimum in late Winter. In opposite to previous straits, the northward Cor- sica Strait transport presents strong seasonal variability, and thus a strong barotropic component related to the wind stress curl.

  19. Evidence of the AMOC interdecadal mode related to westward propagation of temperature anomalies in CMIP5 models

    Science.gov (United States)

    Muir, Les C.; Fedorov, Alexey V.

    2017-03-01

    Climate models show a broad diversity in the simulations of the Atlantic meridional overturning circulation (AMOC) with its leading modes of variability having different amplitudes, periods and driving mechanisms. Theoretical considerations and computations using ocean GCMs suggest that on interdecadal timescales this variability can be controlled by an internal weakly-damped oceanic mode associated with westward propagation of large-scale density anomalies in the North Atlantic Ocean. These anomalies are dominated by temperature with some compensation from salinity. The quadrature phases of this mode include the strengthening of the AMOC, followed a quarter-period later by the development of a broad warm temperature anomaly in the northern Atlantic extending to about 1000 m, then followed by the weakening of the AMOC, and then the upper-ocean cooling. Here, we investigate whether this mode is present in the simulations of Coupled Model Intercomparison Project 5 (CMIP5). Out of the 25 models investigated, we find that more than half of the models exhibit variability consistent with this mode. Some of the relevant modal features includes statistically significant spectral peaks in the band between 15 and 35 years, the westward propagation of density anomalies in the 40°N-60°N latitudinal band, which sets the period of the mode, the existence of the distinct quadrature phases of the AMOC variability, and the predominant effect of temperature on density anomalies.

  20. Geodetic surveys in Messina straits area

    Science.gov (United States)

    Baldi, P.; Achilli, V.; Mulargia, F.; Broccio, F.

    1983-03-01

    By using the fit of theoretical displacements on a fault according to Mindlin and Cheng (1950) dislocation theory, the vertical deformation field (maximum subsidence of 70 cm) associated to the Dec. 28 1908 Messina M=7.0 earthquake is compared to the results of a spirit levelling survey that we performed in the Messina Straits area in 1981 1982. The differences in level from the last levelling campaign in the area, completed in 1970, show that the coastlines have undergone a moderate differential subsidence of about 1 mm/year in the last decade. This is in agreement with the trend observed around 1908 and with the data of the Messina tide-gauge relative to the period 1897 1908 and 1910 1918. The lack of data in the period 1918 1970 does not allow definite conclusions about the vertical tectonic deformations in the area. Recent data on planimetric deformations have shown a South-North relative motion of Sicily. A comparison with the theoretical displacements indicates that a pure dip-slip of 4 cm on the 1908 fault system does explain the observed vertical deformation, but not the horizontal.

  1. On the lifetime and extent of an auroral westward flow channel (AWFC observed during a magnetospheric substorm

    Directory of Open Access Journals (Sweden)

    M. L. Parkinson

    Full Text Available A -190-nT negative bay in the geomagnetic X component measured at Macquarie Island ( -65° L showed that an ionospheric substorm occurred during 09:58 to 11:10 UT on 27 February 2000. Signatures of an auroral westward flow channel (AWFC were observed nearly simultaneously in the backscatter power, LOS Doppler velocity, and Doppler spectral width measured using the Tasman International Geospace Environment Radar (TIGER, a Southern Hemisphere HF SuperDARN radar. Many of the characteristics of the AWFC were similar to those occurring during a polarisation jet (PJ, or subauroral ion drift (SAID event, and suggest that it may have been a pre-cursor to a fully developed, intense westward flow channel satisfying all of the criteria defining a PJ/SAID. A beam-swinging analysis showed that the westward drifts (poleward electric field associated with the flow channel were very structured in time and space, but the smoothed velocities grew to ~ 800 ms-1 (47 mVm-1 during the 22-min substorm onset interval 09:56 to 10:18 UT. Maximum west-ward drifts of >1.3 km s-1 (>77 mVm-1 occurred during a ~ 5-min velocity spike, peaking at 10:40 UT during the expansion phase. The drifts decayed rapidly to ~ 300 ms-1 (18 mVm-1 during the 6-min recovery phase interval, 11:04 to 11:10 UT. Overall, the AWFC had a lifetime of 74 min, and was located near -65° L in the evening sector west of the Harang discontinuity. The large westward drifts were confined to a geographic zonal channel of longitudinal ex-tent >20° (>1.3 h magnetic local time, and latitudinal width ~2° L. Using a half-width of ~ 100 km in latitude, the peak electric potential was >7.7 kV. However, a transient velocity of >3.1 km s-1 with potential >18.4 kV was observed further poleward at the end of the recovery phase. Auroral oval boundaries determined

  2. Changes in the Composition of the Fram Strait Freshwater Outflow

    Science.gov (United States)

    Dodd, Paul; Granskog, Mats; Fransson, Agneta; Chierici, Melissa; Stedmon, Colin

    2016-04-01

    Fram Strait is the largest gateway and only deep connection between the Arctic Ocean and the subpolar oceans. Monitoring the exchanges through Fram Strait allows us to detect and understand current changes occurring in the Arctic Ocean and to predict the effects of those changes on the Arctic and Subarctic climate and ecosystems. Polar water, recirculating Atlantic Water and deeper water masses exported from the Arctic Ocean through western Fram Strait are monitored year-round by an array of moored instruments along 78°50'N, continuously maintained by the Norwegian Polar Institute since the 1990s. Complimentary annual hydrographic sections have been repeated along the same latitude every September. This presentation will focus on biogeochemical tracer measurements collected along repeated sections from 1997-2015, which can be used to identify freshwater from different sources and reveal the causes of variations in total volume of freshwater exported e. g.: pulses of freshwater from the Pacific. Repeated tracer sections across Fram Strait reveal significant changes in the composition of the outflow in recent years, with recent sections showing positive fractions of sea ice meltwater at the surface near the core of the EGC, suggesting that more sea ice melts back into the surface than previously. The 1997-2015 time series of measurements reveals a strong anti-correlation between run-off and net sea ice meltwater inventories, suggesting that run-off and brine may be delivered to Fram Strait together from a common source. While the freshwater outflow at Fram Strait typically exhibits a similar run-off to net sea ice meltwater ratio to the central Arctic Ocean and Siberian shelves, we find that the ratio of run-off to sea ice meltwater at Fram Strait is decreasing with time, suggesting an increased surface input of sea ice meltwater in recent years. In 2014 and 2015 measurements of salinity, δ18O and total alkalinity were collected from sea ice cores as well as the

  3. Peaceful development of cross-strait relations,"one country two systems"Horizon

    Institute of Scientific and Technical Information of China (English)

    YanDekuan

    2015-01-01

    " one country, peaceful reunification" policy put forward, which has existed for more than 30 set. People have proposed the development of cross-strait peace framework. It is necessary for the development of cross-strait peace framework related to cross-strait cultural environment factors, international factors, the development of cross-strait past and future context, strategic and realistic basis for cross-strait interaction were analyzed and discussed. Made more scientific framework for peaceful development of cross-strait on this basis. The paper carried a Taiwanese perspective Islanders psychological and related factors. Unified attitude on the mainland were scanned. For cross-strait peace development context briefly comb. On this basis a simple thinking related factors. Peaceful development of cross-strait relations proposed framework Opinion.

  4. Reading the Planetary Archipelago of the Torres Strait

    Directory of Open Access Journals (Sweden)

    Elizabeth McMahon

    2013-05-01

    Full Text Available This essay makes use of the Western concept of the archipelago as a starting point for an examination of island to island relations in the Torres Strait, Australia, as they are rehearsed in the imaginary domain of story, in both its written and oral modes. The essay deploys Spivak’s notions of planetarity and Bloch’s concept of utopianism as ways of charting the relationship between two Torres Strait stories, one old, one new. In so doing, the essay seeks to identify the capacity of Torres Strait literature and storytelling to re-conceive relations of space and time and to acknowledge a spatial and temporal mobility running parallel to the circumscribed trajectories of late modernity.

  5. Tide and tidal current observation in the Karimata Strait

    Science.gov (United States)

    Wei, Zexun; Fang, Guohong; Sulistiyo, Budi; Dwi Susanto, R.; Setiawan, Agus; Rameyo Adi, Tukul; Qiao, Fangli; Fan, Bin; Li, Shujiang

    2013-04-01

    It is believed that the water exchanges between the South China Sea and the Indonesian Seas are significant, and play an important role in the water mass formation and air-sea interactions of both the South China Sea and Indonesian Seas. It has also been found that the current in Sunda Strait has been obvious seasonal variation, which indicates the water exchange between West Indonesian Seas and India Ocean. In order to make quantitative evaluation of the magnitudes of the exchange, the First Institute of Oceanography (FIO), China, the Agency for Marine and Fisheries Research, Indonesia, and the Lamont-Doheries Earth Observatory, USA established a collaborative program, "The South-China Sea-Indonesian Seas Transport/Exchange (SITE) and Impacts on Seasonal Fish Migration" in 2006. And, they extend and expand the cooperation to Sunda Strait in 2008, the title of the collaborative program was changed to "The South China Sea - Indonesian Seas Transport/Exchange (SITE) and Dynamics of Sunda and Lombok Straits, and Their Impacts on Seasonal Fish Migration". Till now, 12 joint cruises have been conducted since December, 2007. Ten Trawl-Resistant Bottom Mounts (TRBM) have been deployed in the Karimata and Sunda Straits. The TRBMs are equipped with ADCPs and tide gauges for measuring current profiles and sea levels, respectively. The temperature-salinity profiles were measured with ship-board CTD during the cruises. Data obtained in Karimata Strait revealed that a significant water mass transport. This indicates that the Karimata Strait throughflow can greatly impacts the circulation of both the South China Sea and the Indonesian Seas. The data obtained at the 5 stations alone the two sections in the Karimata Strait were used to study the tide and tidal currents in the Karimata Strait. 2 TRBMs were deployed at Section A, as well as 3 at Section B, which lies at the southeast of Section A. Station B1 is in the Gaspar Strait between Bangka Island and Belitung Island, Stations

  6. A Bibliography of the Physical Oceanography of Straits.

    Science.gov (United States)

    1986-11-01

    Kelley (eds.), Univer- description of currents in the Glebinka Strait in Puck sity of Alaska, Fairbanks, pp. 3-37. Bay (Poland). Oceanografia , Gdansk 5...3742. Archivio di Oceanografia E Limnologia 19:65-82. Whitworth, T. and R. G. Peterson (1985). Volume Waldichuk, M. (1957). Physical oceanography of

  7. Readjustments in U.S. Cross-Taiwan Strait Policy

    Institute of Scientific and Technical Information of China (English)

    Sun Shengliang; Ma Zongshi

    2008-01-01

    Washington had all along followed an ambiguity policy over its possible military intervention in a Taiwan contingency. However, recent years have witnessed readjustments towards "double clarity" of a possible military response in case of a Chinese-initiated use of force and potential inaction in the event of a conflict derived from Taiwanese provocations to change the status quo by seeking de jure independence. In other words, it spells a policy shift toward "dual deterrence," namely to deter the Chinese mainland from using force in seeking national reunification and to deter Taiwan from moving toward de jure independence. To prevent such eventuality, Washington made direct appeal to the Taiwan public to make clear its opposition to Taiwan independence.The reasons behind the readjustments are not far to seek. They reflect shifts in U.S. strategic focus, changes in its China policy, political developments on both sides of the Taiwan Strait and President Bush's personal disgust with former Taiwan leader Chen Shuibian's cunning tricks.However, resumption of Cross-Strait dialogue in the wake of the return to power of the Kuomintang (National Party) through the ballot in March may bring about new worries and possible further readjustments in U.S. cross-strait policy after the November presidential elections. Though uncertainties remain, in the pipeline may be an endeavor to prevent excessive cross-strait warmth and a possible tilt of Taiwan to the Chinese Mainland.

  8. Microbial ecological associations in the surface sediments of Bohai strait

    Science.gov (United States)

    Wang, Bin; Liu, Hongmei; Tang, Haitian; Hu, Xiaoke

    2017-09-01

    Microbial communities play key roles in the marine ecosystem. Despite a few studies on marine microbial communities in deep straits, ecological associations among microbial communities in the sediments of shallow straits have not been fully investigated. The Bohai Strait in northern China (average depth less than 20 m) separates the Bohai Sea from the Yellow Sea and has organic-rich sediments. In this study, in the summer of 2014, six stations across the strait were selected to explore the taxonomic composition of microbial communities and their ecological associations. The four most abundant classes were Gammaproteobacteria, Deltaproteobacteria, Bacilli and Flavobacteriia. Temperature, total carbon, depth, nitrate, fishery breeding and cold water masses influenced the microbial communities, as suggested by representational difference and composition analyses. Network analysis of microbial associations revealed that key families included Flavobacteriaceae, Pirellulaceae and Piscirickettsiaceae. Our findings suggest that the families with high phylogenetic diversity are key populations in the microbial association network that ensure the stability of microbial ecosystems. Our study contributes to a better understanding of microbial ecology in complex hydrological environments.

  9. Age, geochemical and isotopic variations in volcanic rocks from the Coastal Range of Taiwan: Implications for magma generation in the Northern Luzon Arc

    Science.gov (United States)

    Lai, Yu-Ming; Song, Sheng-Rong; Lo, Ching-Hua; Lin, Te-Hsien; Chu, Mei-Fei; Chung, Sun-Lin

    2017-02-01

    This paper reports the first systematic analysis of age and geochemical variations in volcanic rocks from the Coastal Range of Taiwan, the Northern Luzon Arc. The rocks, recovered from four main volcanoes, vary from low-K tholeiitic to medium-K calc-alkaline basalts to dacites. The rocks are typical of arc magmatic products, exhibiting enrichment in the large ion lithophile elements and depletion in the high field strength elements. Our new 40Ar/39Ar age data constrain the youngest eruption time in each of the four volcanoes, i.e., from north to south, at 7.2 Ma (Yuemei), 4.2 Ma (Chimei), 6.2 Ma (Chengkuang'ao) and 8.5 Ma (Tuluanshan), respectively. These data indicate that volcanism in the Northern Luzon Arc did not cease progressively from north to south, as previously alleged. The high and broadly uniform Nd isotope ratios [εNd = + 10.1 to + 8.8] and trace element characteristics of the rocks suggest a principal magma source from the depleted mantle wedge. Their overall geochemical variations are ascribed to magma chamber processes. The effects of magmatic differentiation and crustal contamination differ among each volcano, most likely owing to the discrepancy of residence time in individual magma chambers. Consequently, we propose a binary mixing model for the magma generation that involves arc magmas sourced from the depleted mantle wedge and up to 5% crustal contamination with a continental fragment split off from the Eurasian margin.

  10. Influence of a narrow strait connecting a large ocean and a small sea on magnetotelluric data: Gibraltar Strait

    Science.gov (United States)

    González-Castillo, Lourdes; Junge, Andreas; Galindo-Zaldívar, Jesús; Löwer, Alexander

    2015-11-01

    Long period magnetotelluric (LMT) data are generally used as the prime tool to shed light on the conductivity of the deep crust and upper mantle structure. Naturally, LMT data are sensitive to the influence of highly conductive bodies even at far distances. Sea water constitutes the main widespread electrical conductor at shallow levels of the Earth's crust. Its low resistivity values, around 0.25 Ωm, contrast sharply with most geological structures of solid earth. Consequently, the presence of irregular continental borders and varying bathymetries significantly influences LMT parameter, such as phase tensor and tipper vectors. This effect is especially important in areas where large and small oceans are connected by narrow gateways. The Gibraltar Strait (southern Spain) connects the vast Atlantic Ocean with the irregular and relatively small Mediterranean Sea. Several 3D models have been developed in the region nearby the Strait, some featuring a roughly simplified geological structure, to show the influence of seawater on tipper and phase tensor. Here, detailed bathymetry (General Bathymetric Chart of the Oceans, GEBCO) including the coastline is considered in a model that enables us to analyze the influence of the Strait of Gibraltar on LMT data. We stress the significance of the Sea for LMT data interpretation and the development of 3D conductivity models, especially in regions involving complex coastline geometries and bathymetry near narrow straits. Forward modeling studies are essential to accurately appraise the sea influence, which may mask 3D geological structures.

  11. Genetic legacy of the deep subsurface recorded in the outflow channel of a terrestrial serpentinizing seep (Luzon, the Philippines)

    Science.gov (United States)

    Woycheese, K. M.; Meyer-Dombard, D. R.; Cardace, D.; Arcilla, C. A.

    2014-12-01

    The deep subsurface microbial community represents the largest biome on Earth, yet accessing this deep biosphere is challenging. Fluids seep along fractures from aquifers that may support diverse microbial communities, living off hydrogen gas generated by radiolysis, serpentinization, or thermogenic reactions. A serpentinizing seep, emanating fluids as high as pH 11.27, was found to accrete meters-long carbonate terraces in the Zambales ophiolite range (Luzon, the Philippines). Samples were collected at several locations along the Poon Bato (PB) River, focusing primarily on the pools and terraces formed by carbonate rimstone (Figure 1). As serpentinizing fluids are exposed to the atmosphere, dynamic niches are established in surface sediments. We propose that the high pH, reducing, high Ca+2 fluid pool terraces reflect remnants of deep subsurface microbial communities, based on high-throughput 16S rRNA sequencing data. In total, eight samples were collected for environmental DNA analysis. Post-sequence analysis revealed a total of 927126 counts, with an average of 115890.75 counts per sample. Many taxa aligned with cultured representatives of serpentinizing seep-associated taxa, including Bacteroidetes, Clostrida, Chloroflexi, Methylococcales, and Xanthomonadales. Geochemical data indicates an average fluid temperature of 28.9°C, and pH that varies from 9.22-11.27. Total carbon wt.% of solids was highest in a shallow pool shaped by boulders, where calcite precipitation occurred over nearly every surface. Dissolved oxygen (DO%) was highest at PB1 main pool (60%), although a calcite skin had formed along the air-water interface. Dissolved inorganic carbon (DIC) at PB1 main pool was 1.3 ppm, while at PB2 main pool, the DIC was higher (6.0 ppm). The lack of calcite skin may allow more direct access to atmospheric carbon dioxide at PB2. The isotopic value of carbon-13 was depleted at PB1 relative to PB2 (δ13C VPDB -25.4 ‰ versus δ13C VPDB ‰ -17.5, respectively

  12. Textural and chemical variation in phenocrysts from the early eruptions of Lutao volcanic island, the northern Luzon arc

    Science.gov (United States)

    Liu, Y.; Iizuka, Y.; Huang, K.

    2012-12-01

    The Lutao volcanic island at the northern end of Luzon arc was formed by the subduction of South China Sea Plate beneath the Philippine Sea plate. Three edifices on the island were built up by pyroclastic deposits from different eruption stages. In this study, the textural and chemical zonings in phenocrysts are used to characterize the subvolcanic magma chamber for the earliest eruption stage (1.4-2.0 Ma). The high 143Nd/144Nd and 176Hf/177Hf ratios of six volcanic breccias collected from the lowermost layer indicate that they were derived from a common depleted mantle source. However, their compositional variations cannot be explained by simple fractional crystallization. The textures and compositions of the phenocrysts reveal the complication in the magma chamber processes. Compared to the average primitive arc basalts, two basaltic andesites have similar major element compositions with higher incompatible trace element abundances. The un-zoned or normally zoned olivine, plagioclase, and pyroxenes indicate the relatively undisturbed processes (961-1011°C and 2.8-5.5 kb) at the earlier crystallization stage. The peritectic olivine and abundance melt inclusions accompanied by abrupt XAn increase at the rims of plagioclase inferred recharge of H2O-rich mafic melt at later stage, which also triggered rapid eruption. The cryptic magma mixing had limited effect on isotopic signatures and major element variations, but had great chance to modify the bulk trace element abundances. In contrast, plagioclase phenocrysts in four low-mg# basaltic samples contain An-rich dissolved or resorbed cores with abundant melt inclusions, which were formed from rapid decompression of volatile-rich magma at H2O-undersaturated conditions. The calcic plagioclase and minor Mg-rich olivine formed at greater depth were rapidly brought to magma chamber to crystallized sodic plagioclase rim, clinopyroxene, and minor orthopyroxene (954-994°C and 2.1-4.1 kb). The normally zoned clinopyroxene

  13. Anisotropic macroturbulence and diffusion associated with a westward zonal jet: From laboratory to planetary atmospheres and oceans

    Science.gov (United States)

    Galperin, Boris; Hoemann, Jesse; Espa, Stefania; Di Nitto, Gabriella; Lacorata, Guglielmo

    2016-12-01

    Turbulence with inverse energy cascade and its transport properties are investigated experimentally in a flow associated with a westward propagating jet. Turbulence and the jet were produced by an electromagnetic force in a rotating tank filled with an electrolytic saline solution. The parabolic free surface emulated the topographic β effect which evoked the zonation. The spectral and transport flow characteristics were highly anisotropic. Turbulence is diagnosed by exploring the analogy between vertical and horizontal turbulent overturns in, respectively, stably stratified and quasigeostrophic flows which gives rise to a method of potential vorticity (PV) monotonizing. The anisotropization of transport properties of the flow is investigated using the finite scale Lyapunov exponent technique. After initial exponential particle separation, radial (meridional in geophysical and planetary applications) diffusion attains a short-ranged Richardson regime which transitions to the Taylor (scale-independent diffusivity) one. The azimuthal (zonal) diffusion exhibits a double-plateau structure which attains a superdiffusive regime on large scales. The transition to the Taylor regime for the radial diffusion takes place at a scale of turbulence anisotropization. The radial eddy diffusivity in both regimes as well as the transition scale are all determined by the rate of the inverse energy cascade, ɛ , that can be diagnosed by the PV monotonizing. Conversely, ɛ can be deduced from the scale of the Richardson-Taylor regime transition in the radial eddy diffusivity which, thus, provides an additional tool of diagnosing anisotropic macroturbulence with inverse energy cascade.

  14. Anisotropic macroturbulence and diffusion associated with a westward zonal jet: From laboratory to planetary atmospheres and oceans.

    Science.gov (United States)

    Galperin, Boris; Hoemann, Jesse; Espa, Stefania; Di Nitto, Gabriella; Lacorata, Guglielmo

    2016-12-01

    Turbulence with inverse energy cascade and its transport properties are investigated experimentally in a flow associated with a westward propagating jet. Turbulence and the jet were produced by an electromagnetic force in a rotating tank filled with an electrolytic saline solution. The parabolic free surface emulated the topographic β effect which evoked the zonation. The spectral and transport flow characteristics were highly anisotropic. Turbulence is diagnosed by exploring the analogy between vertical and horizontal turbulent overturns in, respectively, stably stratified and quasigeostrophic flows which gives rise to a method of potential vorticity (PV) monotonizing. The anisotropization of transport properties of the flow is investigated using the finite scale Lyapunov exponent technique. After initial exponential particle separation, radial (meridional in geophysical and planetary applications) diffusion attains a short-ranged Richardson regime which transitions to the Taylor (scale-independent diffusivity) one. The azimuthal (zonal) diffusion exhibits a double-plateau structure which attains a superdiffusive regime on large scales. The transition to the Taylor regime for the radial diffusion takes place at a scale of turbulence anisotropization. The radial eddy diffusivity in both regimes as well as the transition scale are all determined by the rate of the inverse energy cascade, ε, that can be diagnosed by the PV monotonizing. Conversely, ε can be deduced from the scale of the Richardson-Taylor regime transition in the radial eddy diffusivity which, thus, provides an additional tool of diagnosing anisotropic macroturbulence with inverse energy cascade.

  15. Variation of the cold intermediate water in the Black Sea exit of the Strait of Istanbul (Bosphorus and its transfer through the strait

    Directory of Open Access Journals (Sweden)

    Huseyin Yuce

    2012-04-01

    Full Text Available The cold intermediate water (CIW, T < 8°C entering the Strait of Istanbul and its variation along the strait have been studied by using monthly conductivity-temperature-depth (CTDdata sets collected during the period from 1996 to 2000. In the northern exit of the strait, CIW is located between the seasonal thermocline and Mediterranean water originating from the lowerlayer of the Sea of Marmara. The thickness of CIW decreases fromApril to October. In the Strait of Istanbul, CIW is observedas a layer of temperature < 14$^{circ}$C. The thickness of thismodified cold intermediate water flowing southwards with the upper layer decreases, while its temperature increases along thestrait due to mixing with adjacent water. In the southern exit of the strait, the modified cold intermediate water is observed during the period from May to October. If CIW exists in the Black Sea exit region of the strait, modified cold water is found inthe Marmara exit region during the same period. The distribution of CIW in the Strait of Istanbul contributes to our understanding of the dynamics of the strait, especially in the summer months.

  16. Human genetic differentiation across the Strait of Gibraltar

    Directory of Open Access Journals (Sweden)

    Sanchez-Mazas Alicia

    2010-08-01

    Full Text Available Abstract Background The Strait of Gibraltar is a crucial area in the settlement history of modern humans because it represents a possible connection between Africa and Europe. So far, genetic data were inconclusive about the fact that this strait constitutes a barrier to gene flow, as previous results were highly variable depending on the genetic locus studied. The present study evaluates the impact of the Gibraltar region in reducing gene flow between populations from North-Western Africa and South-Western Europe, by comparing formally various genetic loci. First, we compute several statistics of population differentiation. Then, we use an original simulation approach in order to infer the most probable evolutionary scenario for the settlement of the area, taking into account the effects of both demography and natural selection at some loci. Results We show that the genetic patterns observed today in the region of the Strait of Gibraltar may reflect an ancient population genetic structure which has not been completely erased by more recent events such as Neolithic migrations. Moreover, the differences observed among the loci (i.e. a strong genetic boundary revealed by the Y-chromosome polymorphism and, at the other extreme, no genetic differentiation revealed by HLA-DRB1 variation across the strait suggest specific evolutionary histories like sex-mediated migration and natural selection. By considering a model of balancing selection for HLA-DRB1, we here estimate a coefficient of selection of 2.2% for this locus (although weaker in Europe than in Africa, which is in line with what was estimated from synonymous versus non-synonymous substitution rates. Selection at this marker thus appears strong enough to leave a signature not only at the DNA level, but also at the population level where drift and migration processes were certainly relevant. Conclusions Our multi-loci approach using both descriptive analyses and Bayesian inferences lead to

  17. Tidal and residual currents in the Bransfield Strait, Antarctica

    Directory of Open Access Journals (Sweden)

    O. López

    Full Text Available During the 1992-1993 oceanographic cruise of the Spanish R/V Hespérides, recording equipment was deployed in the Bransfield Strait. Six Aanderaa RCM7 current meters and three Aanderaa WLR7 tide gauges were successfully recovered after an operation period of 2.5 months. Relevant features of the time series obtained are presented and discussed in this paper. The emphasis is placed on the tidal character of the currents and the relative importance of tidal flow in the general hydrodynamics of the strait. For these purposes a dense grid of hydrographic stations, completed during the BIOANTAR 93 cruise, is used. Preliminary geostrophic calculations relative to a 400 m depth, yield current velocities of around 0.20 m s-1 in the study area, whereas the magnitude of tidal currents is seen to be 0.30-0.40 m s-1.

  18. Management and control of pollution in Inner Johore Strait.

    Science.gov (United States)

    Koh, H L; Lim, P E; Midun, Z

    1991-10-01

    Coastal waters in South Johore, Malaysia are polluted to various degrees. The major pollution sources are domestric wastes from human settlements, agro-based wastes from palm oil mills and rubber processing factories, industrial effluents from industrial estates and discharges from animal farms. These pollution problems have adversely affected resources such as fisheries, recreational potential as well as the general aesthetic quality of the coastal environment particularly the Inner Johore Strait. Hence proper management and control measures are urgently needed to protect and further enhance the water quality to ensure environmentally sustainable development. This study examines various management options to control the pollution in the Inner Johore Strait. The options involve partial opening as well as complete removal of the Causeway to improve the tidal flow for more effective dilution and dispersion of pollutants. Computer simulation models are used to assess the impacts of the proposed options.

  19. Shared medical appointments for Aboriginal and Torres Strait Islander men.

    Science.gov (United States)

    Stevens, John A; Dixon, John; Binns, Andrew; Morgan, Bob; Richardson, Jeff; Egger, Garry

    2016-06-01

    Aboriginal and Torres Strait Islander health is generally the worst of any population group in Australia. Inaccessibility to health services is one possible cause of this. Shared medical appointments (SMAs) appear to be a culturally competent and appropriate way of improving access to, and the quality of, primary healthcare services for Aboriginal and Torres Strait Islander peoples. The objective of this article is to assess the acceptability and appropriateness of SMAs as an adjunct process in primary care for Aboriginal and Torres Strait Islander men. As part of a broader study on SMAs, three SMA sessions were delivered at an Aboriginal men's health centre in northern New South Wales. One-day training sessions in SMA facilitation were also provided to two groups of 12-14 Aboriginal health workers (AHWs). Mixed methods were used to assess patient and provider satisfaction, subjective outcomes, and operational procedures in the SMA groups, as well as interest in the SMA process by AHWs. Satisfaction with SMAs among Aboriginal men was unanimously positive, with the numbers in the group increasing over time. Patients most enjoyed the 'yarn up' nature of SMAs with peer support, which reduced the 'scary' and culturally 'unnatural' nature of one-on-one consultations with a general practitioner (GP). AHWs who were trained to a level to conduct SMAs saw this as an effective way of improving cultural competence in, and accessibility of, their various Aboriginal health services. The results, though not generalisable, suggest that SMAs may offer a culturally safe and appropriate tool to enhance Aboriginal and Torres Strait Islander peoples' access to primary care.

  20. On summer stratification and tidal mixing in the Taiwan Strait

    Institute of Scientific and Technical Information of China (English)

    Jia ZHU; Jianyu HU; Zhiyu LIU

    2013-01-01

    On continental shelves,a front that separates the sea into well-mixed and stratified zones is usually formed in warm seasons due to spatial variations of tidal mixing.In this paper,using eight years of in situ hydrographic observations,satellite images of sea surface temperature (SST) and chlorophyll-a (Chl-a) concentration,and results of a tidal model,we investigate summer stratification in the Taiwan Strait and its dependence on tidal mixing,upwelling,and river diluted water plumes.In most regions of the strait the dominant role of tidal mixing in determining the thermohaline structure is confirmed by the correlation between the two; there are some regions,however,where thermohaline structttre varies in different ways owing to significant influences ofupwelling and river diluted water plumes.The well-mixed regions are mainly distributed on the Taiwan Bank and in the offshore regions offthe Dongshan Island,Nanao Island,and Pingtan Island,while the northern and central Taiwan Strait and the region south of the Taiwan Bank are stratified.The critical Simpson-Hunter parameter for the region is estimated to be 1.78.

  1. Large sea ice outflow into the Nares Strait in 2007

    DEFF Research Database (Denmark)

    Kwok, R.; Pedersen, L.T.; Gudmandsen, Preben

    2010-01-01

    ice in the 13-year record between 1997 and 2009. The 2007 area and volume outflows of 87 x 10(3) km(2) and 254 km(3) are more than twice their 13-year means. This contributes to the recent loss of the thick, multiyear Arctic sea ice and represents similar to 10% of our estimates of the mean ice export......Sea ice flux through the Nares Strait is most active during the fall and early winter, ceases in mid- to late winter after the formation of ice arches along the strait, and re-commences after breakup in summer. In 2007, ice arches failed to form. This resulted in the highest outflow of Arctic sea...... at Fram Strait. Clearly, the ice arches control Arctic sea ice outflow. The duration of unobstructed flow explains more than 84% of the variance in the annual area flux. In our record, seasonal stoppages are always associated with the formation of an arch near the same location in the southern Kane Basin...

  2. Formation of wind-driven ice bridges in narrow straits

    Science.gov (United States)

    Rallabandi, Bhargav; Zheng, Zhong; Winton, Michael; Stone, Howard A.

    2016-11-01

    An ice bridge is a static arch made of tightly packed ice that can be formed when sea ice flows through a narrow strait between landmasses. The formation of a stable ice arch prevents the further flow of sea ice into warmer oceans, and therefore plays an important role in the regulation of the local climate and ecology and to an extent, the mass balance of Arctic ice. While ice bridges are a seasonal phenomenon in many parts of the Canadian Archipelago, the process of their formation and breakup is poorly understood. Using thin-layer theory along with dynamic sea ice models widely used in climate modeling, we develop a reduced-order description of wind-driven ice bridge formation in long, narrow straits. Our theory predicts a critical static condition for arrested flow that involves the ice properties (thickness and compactness), the geometry of the channel, and the magnitude of the wind stress. Further, we show that in a channel of varying shape and under a constant wind stress, a spatially uniform ice field evolves towards a steady state with discontinuities in its properties, consistent with observed mechanisms of ice bridge formation. The reduced-order model thus provides a predictive tool for the flow and stoppage of sea ice in straits.

  3. Tidal energy resource complexity in a large strait: The Karori Rip, Cook Strait

    Science.gov (United States)

    Stevens, C. L.; Smith, M. J.; Grant, B.; Stewart, C. L.; Divett, T.

    2012-02-01

    Successful extraction of tidal stream energy will require a good understanding of flow at a range of scales, including those relating to average energy, variability in energy supply and fatigue. Current and turbulence measurements from the Karori Rip area of Cook Strait, the prime focal region of open-water tidal stream electricity generation in New Zealand, are described. A key issue is that a significant portion of the energy is contained in waters deeper than normally considered for energy extraction. Here we compare shallow and deep sites. Velocity data were derived from acoustic Doppler current profiler moorings, as well as spatial surveys and show flow magnitudes reaching 3.4 m s -1 in the shallow regions. The maximum speeds in both shallow and deep sites were typically located in the upper part of the measured water column although moored acoustic Doppler current profiler (ADCP) observations showed some complexity in this regard. Benthic boundary-layers were resolved in the bottom ˜20 m of the water column. Measured turbulent kinetic energy dissipation rates ɛ exceeded 10 -5 m 2 s -3 and estimated maximum ɛ is a factor of 10 greater. This was not distributed evenly through the water column, with stratification and velocity shear clearly persisting, especially around the turn of the tide. The implications for tidal stream energy are that (i) there is sufficient energy resource in the region for a moderate sized array of turbines, (ii) the vertical variability in the flow speed suggests turbines that can operate near the surface would be more effective at accessing the resource, (iii) stratification may persist and influence the scales of turbulence and (iv) wave-current interaction effects will influence any near-surface structure as well as vessel operations.

  4. Xenarcturus spinulosus Sheppard, 1957 (Crustacea, Isopoda, Valvifera): Redescription of a specimen from the Strait of Magellan

    NARCIS (Netherlands)

    Park, Ja-Yang

    1995-01-01

    A redescription of a primitive arcturid species, Xenarcturus spinulosus, from the Strait of Magellan is presented with discussion of the systematic position of the monotypical subfamily Xenarcturinae.

  5. A Strait Comparison: Lessons Learned from the 1915 Dardanelles Campaign in the Context of a Strait of Hormuz Closure Event

    Science.gov (United States)

    2011-09-01

    the Dardanelles through the lens of such an event, distill a number of recommendations for the United States and its Coalition partners relevant to...knots going against the current of the Straits, were to steam past the minefields, turn, and sweep them coming back downstream. Seven trawlers set...principle, be increased to 11 MBD using drag -reducing agents [23]. 37 Saudi Arabia and the UAE, and Iran has a large, restive population that, in

  6. Recirculation in the Fram Strait and transports of water in and north of the Fram Strait derived from CTD data

    Directory of Open Access Journals (Sweden)

    M. Marnela

    2013-05-01

    Full Text Available The volume, heat and freshwater transports in the Fram Strait are estimated from geostrophic computations based on summer hydrographic data from 1984, 1997, 2002 and 2004. In these years, in addition to the usually sampled section along 79° N, a section between Greenland and Svalbard was sampled further north. Quasi-closed boxes bounded by the two sections and Greenland and Svalbard can then be formed. Applying conservation constraints on these boxes provides barotropic reference velocities. The net volume flux is southward and varies between 2 and 4 Sv. The recirculation of Atlantic water is about 2 Sv. Heat is lost to the atmosphere and the heat loss from the area between the sections averaged over the four years is about 10 TW. The net heat (temperature transport is 20 TW northward into the Arctic Ocean, with large interannual differences. The mean net freshwater added between the sections is 40 mSv and the mean freshwater transport southward across 79° N is less than 60 mSv, indicating that most of the liquid freshwater leaving the Arctic Ocean through Fram Strait in summer is derived from sea ice melt in the northern vicinity of the strait. In 1997, 2001 and 2003 meridional sections along 0° longitude were sampled and in 2003 two smaller boxes can be formed, and the recirculation of Atlantic water in the strait is estimated by geostrophic computations and continuity constraints. The recirculation is weaker close to 80° N than close to 78° N, indicating that the recirculation is mainly confined to the south of 80° N. This is supported by the observations in 1997 and 2001, when only the northern part of the meridional section, from 79° N to 80° N, can be computed with the constraints applied. The recirculation is found strongest close to 79° N.

  7. Recirculation in the Fram Strait and transports of water in and north of the Fram Strait derived from CTD data

    Directory of Open Access Journals (Sweden)

    M. Marnela

    2012-10-01

    Full Text Available The volume, heat and freshwater transports in the Fram Strait are estimated from geostrophic computations based on summer hydrographical data from 1984, 1997, 2002 and 2004. In these years, in addition to the usually sampled section along 79° N, a section between Greenland and Svalbard was sampled further north. Quasi-closed boxes bounded by the two sections and Greenland and Svalbard can then be formed and conservation constraints applied on the boxes. The net volume flux is southward and varies between 2 and 4 Sv. The recirculation of Atlantic water is about 2 Sv. Heat is lost to the atmosphere and the heat loss averaged for the four boxes is about 10 TW and the net heat (temperature transport is 20 TW northward into the Arctic Ocean, with large interannual differences. The mean net freshwater added between the sections is 40 mSv and the mean freshwater transport southward across 79° N is less than 60 mSv, indicating that most of the liquid freshwater leaving the Arctic Ocean through Fram Strait in summer derives from sea ice melt in the northern vicinity of the strait.

    In 1997, 2001 and 2003 meridional sections along 0° longitude were sampled and in 2003 two smaller boxes can be formed, and the recirculation of Atlantic water in the strait is estimated by geostrophic computations and continuity constraints. The recirculation is weaker close to 80° N than close to 78° N, indicating that the recirculation is mainly confined to south of 80° N. This is supported by the observations in 1997 and 2001, when only the northern part of the meridional section, from 79° N to 80° N, can be computed with the constraints applied. The recirculation is found strongest close to 79° N.

  8. Glacimarine sedimentation in Petermann Fjord and Nares Strait, NW Greenland

    Science.gov (United States)

    Hogan, Kelly; Jakobsson, Martin; Mayer, Larry; Mix, Alan; Nielsen, Tove; Kamla, Elina; Reilly, Brendan; Heirman, Katrina An; Stranne, Christian; Mohammed, Rezwan; Eriksson, Bjorn; Jerram, Kevin

    2017-04-01

    Here we build on preliminary results from 6500 line-km of high-resolution chirp sub-bottom profiles (2-7 kHz) acquired in Petermann Fjord and Nares Strait during the Petermann 2015 Expedition of the Swedish icebreaker Oden. We map the unlithified sediment cover in Peterman Fjord, which consists of up to 3 conformable "drape" units and calculate volumes of this assumed "post-glacial" fill. In Nares Strait we have mapped sediment volumes in local basins just beyond the sill at the Petermann Fjord-mouth: do these sediments represent material flushed out from the grounding zone of Petermann Glacier when it was grounded at the sill? In this vein, and interestingly, some of the thickest sediments that we observe are found close to a grounding-zone wedge (GZW) in Nares Strait that represents a former grounding zone of ice retreating southwards through the strait. We also map conformable units across Nares Strait and consider the similarities between these and the sediment units in the fjord. Do the strong reflections between the units represent the same climatic, oceanographic or process-shift both inside and outside the fjord? We also aim to tie our new acoustic stratigraphy to sediment-core data (lithofacies, dates) and, therefore, to comment on the age of the mapped sediment units and present ideas on the glacimarine flux of material to the Petermann-Nares system. Primary sediment delivery to the seafloor in this environment is thought to be predominantly through sedimentation from meltwater plumes but also of iceberg-rafted debris (IRD). However, sediment redeposition by slope failures on a variety of scales also occurs and has focussed sediments into discrete basins where the seafloor is rugged. This work - which aims to relate past sediment, meltwater and iceberg fluxes to changes in climate - will help us to identify how the system has responded to a past global warming event, namely the last deglaciation. This is particularly relevant in light of the recent

  9. Hydrological, plankton and pigment observations in the Makassar Strait, Madura Strait and Eastern Java Sea by the R.V. Samudera, April 16 to May 19, 1975 (NODC Accession 7700306)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Zooplankton and chemical data were collected using net and bottle casts from the R.V. SAMUDERA in the Makassar Strait, Madura Strait and Eastern Java Sea from 16...

  10. Middle-Miocene (Serravallian) temperate carbonates in a seaway connecting the Atlantic Ocean and the Mediterranean Sea (North Betic Strait, S Spain)

    Science.gov (United States)

    Braga, Juan C.; Martín, José M.; Aguirre, Julio; Baird, Catherine D.; Grunnaleite, Ivar; Jensen, Niels Bo; Puga-Bernabéu, Angel; Sælen, Gunnar; Talbot, Michael R.

    2010-03-01

    Miocene deposits in the contact area between the Prebetic and Subbetic domains (Betic Cordillera, S Spain) record the last stages of marine deposition on the southern Iberian margin and the final closure of the North Betic Strait in the early Tortonian (Late Miocene). Serravallian (Middle Miocene) shallow-water carbonates and mixed carbonate-siliciclastics formed on a platform at the southern margin of the North Betic Strait. These shallow-water deposits, informally termed the La Escalera Formation, onlap an erosion surface carved into underlying Miocene and older rocks. Carbonate components are mainly bryozoans, coralline red algae, molluscs, and benthic and planktonic foraminifers, typical of heterozoan lithofacies. Several facies types can be distinguished based on different grain sizes and sedimentary structures. Large-scale geometries and stratigraphic facies relationships indicate that the La Escalera Formation was deposited on a homoclinal ramp attached to a deeply eroded, emergent relief to the south. A beach system developed at the southern margin, with backshore lagoons and local incursions of coarse terrigenous sediments. Seawards of the beach system was a submarine-dune belt that extended over several square kilometres at the northeastern end of the La Escalera Formation. Longshore currents shifted submarine dunes to the northeast. Maximum production of carbonate skeletons took place seawards of the dune field. From this factory area, skeletal debris was moved landwards and incorporated into the dunes and beaches, whereas other skeletal particles were transported downslope by storms and fed a facies belt with hummocky and swaley cross-stratified sediments. The finest-grained particles accumulated below a storm-wave base, along with significant planktic debris. Carbonate deposits change laterally westwards to terrigenous sediments formed in similar facies belts. Terrigenous influx limited carbonate production on the western part of the ramp by disturbing

  11. Sexual maturity cycle and spawning of Greenland halibut Reinhardtius hippoglossoides in the Davis Strait

    DEFF Research Database (Denmark)

    Gundersen, A. C.; Stenberg, Claus; Fossen, I.

    2010-01-01

    Female sexual maturation cycle and the main spawning time of Greenland halibut Reinhardtius hippoglossoides in the Davis Strait were studied through regularly collected samples during 1 year starting in spring 2003. Samples were collected from the southern slope of the Davis Strait Ridge between ...

  12. 33 CFR 117.169 - Mare Island Strait and the Napa River.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Mare Island Strait and the Napa River. 117.169 Section 117.169 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Strait and the Napa River. (a) The draw of the Mare Island Drawbridge, mile 2.8, at Vallejo shall open...

  13. Improving the Participation and Engagement of Aboriginal and Torres Strait Islander Students in Business Education

    Science.gov (United States)

    Dang, Thi Kim Anh; Vitartas, Peter; Ambrose, Kurt; Millar, Hayley

    2016-01-01

    Most Australian universities have among their goals to increase the number of Aboriginal and Torres Strait Islander students at their institutions. In the Australian higher education context, Aboriginal and Torres Strait Islander students are seriously under-represented, particularly in business education compared to other disciplines. An…

  14. The Holocene History of Nares Strait: Transition from Glacial Bay to Arctic-Atlantic Throughflow

    DEFF Research Database (Denmark)

    Jennings, Anne; Sheldon, Christina; Cronin, Thomas

    2011-01-01

    Retreat of glacier ice from Nares Strait and other straits in the Canadian Arctic Archipelago after the end of the last Ice Age initiated an important connection between the Arctic and the North Atlantic Oceans, allowing development of modern ocean circulation in Baffin Bay and the Labrador Sea. ...

  15. 75 FR 70818 - Traffic Separation Schemes: In the Strait of Juan de Fuca and Its Approaches; in Puget Sound and...

    Science.gov (United States)

    2010-11-19

    ... sight-obscured, right-angle turn in the presence of strong currents and numerous small craft. 7... Fuca and Its Approaches; in Puget Sound and Its Approaches; and in Haro Strait, Boundary Pass, and the... Strait of Juan de Fuca and its approaches, in Puget Sound and its approaches, and in Haro Strait...

  16. Taiwan’s Security Calculus of Cross-­Strait Migration

    Directory of Open Access Journals (Sweden)

    Ching Chang

    2015-08-01

    Full Text Available Migration across the Taiwan Strait is relatively insignificant by its scale but it is indeed indisputably politically sensitive. Given the long-term political separation and military rivalry across the Taiwan Strait in the past six decades while both sides of the Taiwan Strait nevertheless intensively engaged each other economically, commercially and culturally, a social trend of cross-Strait migration inevitably results. There are various interpretations on such a demographic development which has raised security concerns, which are in turn creating a biased judiciary arrangement on the migration activities. What are the factors behind the security calculus of cross-Strait migration? How can the security calculus justify its arguments and subsequently maintain unequal treatments with respect to cross-Strait immigrants? Are the rationales for maintaining a tight grip on cross-Strait migration in line with the political ideal proclaimed by the political factions in Taiwan still sensible? What is the potential for the trend of cross-Strait migration affecting the security calculus in the future? On the other hand, for the migration from Taiwan to Mainland China, how influential can it be on the security decision-making process of the Beijing leadership? Is there any impact possibly caused by cross-Strait migration – and is it essentially overstated? Or alternatively, is the overstated influence potentially caused by cross-Strait migration an intentionally staged political myth? What are the substantial impacts actually ever achieved by cross-Strait migration on the security dimension? What is the self-fulfilled conviction of cross-Strait migration? For all the inquiries noted above, the author of this paper would like to scrutinize the truth and separate it from numerous myths ever advocated by the different factions in Taiwan politics. A sound and neutral judgment to tell the exact influences likely enacted by cross-Strait migration would

  17. Observed Volume Fluxes and Mixing in the Dardanelles Strait

    Science.gov (United States)

    2013-10-04

    Laboratory (NRL) and the NATO Undersea Research Center ( NURC ; cur- rently known as the NATO Center for Maritime Research and Experimentation, CMRE...Dardanelles Strait as a part of the TSS08 ( NURC project) and EPOS (NRL project) programs. The deployment began at the end of August 2008 and ended at...previously known as the NATO NURC ) who sup- ported and helped to organi/e and fund cruises to the TSS on the R.’V Alli- ance. We arc also grateful for

  18. How can GPs drive software changes to improve healthcare for Aboriginal and Torres Strait Islanders peoples?

    Science.gov (United States)

    Kehoe, Helen

    2017-01-01

    Changes to the software used in general practice could improve the collection of the Aboriginal and Torres Strait Islander status of all patients, and boost access to healthcare measures specifically for Aboriginal and Torres Strait Islander peoples provided directly or indirectly by general practitioners (GPs). Despite longstanding calls for improvements to general practice software to better support Aboriginal and Torres Strait Islander health, little change has been made. The aim of this article is to promote software improvements by identifying desirable software attributes and encouraging GPs to promote their adoption. Establishing strong links between collecting Aboriginal and Torres Strait Islander status, clinical decision supports, and uptake of GP-mediated health measures specifically for Aboriginal and Torres Strait Islander peoples - and embedding these links in GP software - is a long overdue reform. In the absence of government initiatives in this area, GPs are best placed to advocate for software changes, using the model described here as a starting point for action.

  19. Oil spills prediction in the Bonifacio strait area, western Mediterranean

    Directory of Open Access Journals (Sweden)

    A. Cucco

    2012-02-01

    Full Text Available An innovative forecasting system of the coastal marine circulation has been implemented in the Bonifacio Strait area, between Corsica and Sardinia, using a numerical approach to facilitate the rapid planning and coordination of remedial actions to oil spill emergencies at sea by local authorities. Downscaling and nesting techniques from regional to coastal scale and a 3-D hydrodynamic numerical model, coupled with a wind wave model, are the core of the integrated Bonifacio Strait system. Such a system is capable to predict the sea state and the dispersion of hydrocarbon spills in the area, providing the forecasts on oil spills through an easy-to-use graphical user interface. Scenarios and risk maps have been created to identify the most risky areas to oil pollution in relation to vessels traffic. The backward investigation technique has been exploited to trace the most probable area from which pollution was generated. The system has been operationally verified in January 2011 when an oil spill occurred in the area. Finally output data are daily released providing forecasting services to end-users through the web.

  20. On locating local earthquakes at the Messina Strait network

    Directory of Open Access Journals (Sweden)

    G. NERI

    1980-06-01

    Full Text Available A computer program (HYPOSTRE has been elaborated to determine
    the hypocentral parameters of local earthquakes, even when they are recorded
    by a small number of stations. These are the most frequent conditions
    prevailing around the Strait of Messina.
    The program employs the first arrivals of P and S waves, a model of
    local crust consisting of four plane and parallel layers, and an algorithm
    based on that of Geiger.
    HYPOSTRE can determine simultaneously the four unknowns X, cp, h
    and H (HYPOSTRE 4 and can calculate the epicentral coordinate separately
    from focal depth (HYPOSTRE 2. In both cases the program follows
    an iterative process. In particular, HYPOSTRE 2 shows convergence towards
    a final solution, through a series of « damped » approximations.
    The application of HYPOSTRE to about twenty earthquakes, which
    have occured in the Strait of Messina and in the Gulf of Patti, demonstrates
    a good convergence and a general stability of results.
    Finally, comparison with analogous determinations — carried out by
    other programs, with different crustal models and using a greater number
    of recorded data — confirms the reliability of HYPOSTRE.

  1. Anomalous dispersion of sea ice in the Fram Strait region

    Science.gov (United States)

    Gabrielski, A.; Badin, G.; Kaleschke, L.

    2015-03-01

    The single-particle dispersion of sea ice in the Fram Strait region is investigated using ice drift buoys deployed from 2002 to 2009 within the Fram Strait Cyclones and the Arctic Climate System Study campaigns. A new method to estimate the direction of the mean flow, based on a satellite drift product, is introduced. As a result, the bias in the dispersion introduced by the mean flow is eliminated considering only the displacements of the buoys in the cross-stream direction. Results show an absolute dispersion growing quadratically in time for the first 3 days and an anomalous dispersion regime exhibiting a strongly self-similar scaling following a 5/4 power law for time scales larger than 6 days persisting over the whole time series of length 32 days. The non-Gaussian distribution of the velocity fluctuations with a skewness of -0.15 and a kurtosis of 7.33 as well as the slope of the Lagrangian frequency spectrum between -2 and -1 are in agreement with the anomalous diffusion regime. Comparison with data from the International Arctic Buoy Program yields similar results with an anomalous dispersion starting after 10 days and persisting over the whole time series of length 50 days. The results suggest the presence of deformation and shear acting on the sea ice dispersion. The high correlation between the cross-stream displacements and the cross-stream wind velocities shows the important role of the wind as a source for the anomalous dispersion.

  2. Oil spills prediction in the Bonifacio strait area, western Mediterranean

    Science.gov (United States)

    Cucco, A.; Ribotti, A.; Olita, A.; Fazioli, L.; Sorgente, B.; Sinerchia, M.; Satta, A.; Perilli, A.; Borghini, M.; Schroeder, K.; Sorgente, R.

    2012-02-01

    An innovative forecasting system of the coastal marine circulation has been implemented in the Bonifacio Strait area, between Corsica and Sardinia, using a numerical approach to facilitate the rapid planning and coordination of remedial actions to oil spill emergencies at sea by local authorities. Downscaling and nesting techniques from regional to coastal scale and a 3-D hydrodynamic numerical model, coupled with a wind wave model, are the core of the integrated Bonifacio Strait system. Such a system is capable to predict the sea state and the dispersion of hydrocarbon spills in the area, providing the forecasts on oil spills through an easy-to-use graphical user interface. Scenarios and risk maps have been created to identify the most risky areas to oil pollution in relation to vessels traffic. The backward investigation technique has been exploited to trace the most probable area from which pollution was generated. The system has been operationally verified in January 2011 when an oil spill occurred in the area. Finally output data are daily released providing forecasting services to end-users through the web.

  3. Sensitivity analysis of the physical dynamics of the Fly River plume in Torres Strait

    Science.gov (United States)

    Li, Yanfang; Martins, Flavio; Wolanski, Eric

    2017-07-01

    The intrusion in the Torres Strait of the Fly River plume polluted by mine tailings is an international water issue. To investigate the physical mechanisms involved in the intrusion process, numerical simulations were conducted to assess the relative influence of the bathymetry and the external forcing, namely the tides, the mean sea level slope across the strait, river runoff and wind forcing. The wind data from Horn Island, the only long-term wind station in the Torres Strait, is shown to be unreliable due to orographic effects. Mean sea level data from altimetry compare well with those from tide gauges in these shallow, reef-studded waters. The wind has a dominant effect on the mean sea level at seasonal and inter-annual periods. The resulting mean sea level difference across the strait fluctuated seasonally and strongly influenced the intrusion of the Fly River plume in the Torres Strait. The 3D finite-volume MOHID model reproduced the observation that the river plume starts by being stratified in the Gulf of Papua where it originates, and it mixes vertically when it enters the Torres Strait. The MOHID and the SLIM models were applied with different resolution to the Torres Strait and responded similarly to the external forcings. The predicted and observed Fly River plume intrusion in the eastern Torres Strait agreed well with each other, including the formation of patches due to flow reversals. However, the two models predicted a widely different Fly River plume in its far field in the western Torres Strait, the differences were attributed to the different bathymetry in the Australian and British-US bathymetry data for these poorly charted waters, which demonstrated the importance of the details of the bathymetry in controlling the extent of plume intrusion.

  4. Beach morphology and coastline evolution in the southern Bohai Strait

    Science.gov (United States)

    Zhang, Wei; Wu, Jianzheng; Li, Weiran; Zhu, Longhai; Hu, Rijun; Jiang, shenghui; Sun, Yonggen; Wang, Huijuan

    2015-10-01

    The beach studied in this paper spans a length of 51 km and is one of several long sandy beaches in the southern Bohai Strait. Due to the obstruction of islands in the northeast and the influence of the underwater topography, the wave environment in the offshore area is complex; beach types and sediment transport characteristics vary along different coasts. The coastlines extracted from six aerial photographs in different years were compared to demonstrate the evolving features. Seven typical beach profiles were selected to study the lateral beach variation characteristics. Continuous wind and wave observation data from Beihuangcheng ocean station during 2009 were employed for the hindcast of the local wave environment using a regional spectral wave model. Then the results of the wave hindcast were incorporated into the LITDRIFT model to compute the sediment transport rates and directions along the coasts and analyze the longshore sand movement. The results show that the coastline evolution of sand beaches in the southern Bohai Strait has spatial and temporal variations and the coast can be divided into four typical regions. Region (I), the north coast of Qimudao, is a slightly eroded and dissipative beach with a large sediment transport rate; Region (II), the southwest coast of Gangluan Port, is a slightly deposited and dissipative beach with moderate sediment transport rate; Region (III), in the central area, is a beach that is gradually transformed from a slightly eroded dissipative beach to a moderately or slightly strong eroded bar-trough beach from west to east with a relatively moderate sediment transport rate. Region (IV), on the east coast, is a strongly eroded and reflective beach with a weak sediment transport rate. The wave conditions exhibit an increasing trend from west to east in the offshore area. The distribution of the wave-induced current inside the wave breaking region and the littoral sediment transport in the nearshore region exhibit a gradual

  5. Aqueous fluids and sedimentary melts as agents for mantle wedge metasomatism, as inferred from peridotite xenoliths at Pinatubo and Iraya volcanoes, Luzon arc, Philippines

    Science.gov (United States)

    Yoshikawa, Masako; Tamura, Akihiro; Arai, Shoji; Kawamoto, Tatsuhiko; Payot, Betchaida D.; Rivera, Danikko John; Bariso, Ericson B.; Mirabueno, Ma. Hannah T.; Okuno, Mitsuru; Kobayashi, Tetsuo

    2016-10-01

    Mantle xenoliths entrained in subduction-zone magmas often record metasomatic signature of the mantle wedge. Such xenoliths occur in magmas from Iraya and Pinatubo volcanoes, located at the volcanic front of the Luzon arc in the Philippines. In this study, we present the major element compositions of the main minerals, trace element abundances in pyroxenes and amphiboles, and Nd-Sr isotopic compositions of amphiboles in the peridotite xenoliths from Pinatubo volcano. The data indicate enrichment in fluid-mobile elements, such as Rb, Ba, U, Pb, and Sr, and Nd-Sr isotopic ratios relative to those of mantle. The results are considered in terms of mixing of asthenospheric mantle and subducting oceanic crustal components. The enrichments observed in the Pinatubo mantle xenoliths are much less pronounced than those reported for the Iraya mantle xenoliths. This disparity suggests differences in the metasomatic agents contributing to the two suites; i.e., aqueous fluids infiltrated the mantle wedge beneath the Pinatubo volcano, whereas aqueous fluids and sediment-derived melts infiltrated the mantle wedge beneath the Iraya volcano.

  6. The amphibians and reptiles of Luzon Island, Philippines, VIII: the herpetofauna of Cagayan and Isabela Provinces, northern Sierra Madre Mountain Range

    Science.gov (United States)

    Brown, Rafe M.; Siler, Cameron D.; Oliveros, Carl. H; Welton, Luke J.; Rock, Ashley; Swab, John; Weerd, Merlijn Van; van Beijnen, Jonah; Jose, Edgar; Rodriguez, Dominic; Jose, Edmund; Diesmos, Arvin C.

    2013-01-01

    Abstract We provide the first report on the herpetological biodiversity (amphibians and reptiles) of the northern Sierra Madre Mountain Range (Cagayan and Isabela provinces), northeast Luzon Island, Philippines. New data from extensive previously unpublished surveys in the Municipalities of Gonzaga, Gattaran, Lasam, Santa Ana, and Baggao (Cagayan Province), as well as fieldwork in the Municipalities of Cabagan, San Mariano, and Palanan (Isabela Province), combined with all available historical museum records, suggest this region is quite diverse. Our new data indicate that at least 101 species are present (29 amphibians, 30 lizards, 35 snakes, two freshwater turtles, three marine turtles, and two crocodilians) and now represented with well-documented records and/or voucher specimens, confirmed in institutional biodiversity repositories. A high percentage of Philippine endemic species constitute the local fauna (approximately 70%). The results of this and other recent studies signify that the herpetological diversity of the northern Philippines is far more diverse than previously imagined. Thirty-eight percent of our recorded species are associated with unresolved taxonomic issues (suspected new species or species complexes in need of taxonomic partitioning). This suggests that despite past and present efforts to comprehensively characterize the fauna, the herpetological biodiversity of the northern Philippines is still substantially underestimated and warranting of further study. PMID:23653519

  7. The amphibians and reptiles of Luzon Island, Philippines, VIII: the herpetofauna of Cagayan and Isabela Provinces, northern Sierra Madre Mountain Range.

    Science.gov (United States)

    Brown, Rafe M; Siler, Cameron D; Oliveros, Carl H; Welton, Luke J; Rock, Ashley; Swab, John; Weerd, Merlijn Van; van Beijnen, Jonah; Jose, Edgar; Rodriguez, Dominic; Jose, Edmund; Diesmos, Arvin C

    2013-01-01

    We provide the first report on the herpetological biodiversity (amphibians and reptiles) of the northern Sierra Madre Mountain Range (Cagayan and Isabela provinces), northeast Luzon Island, Philippines. New data from extensive previously unpublished surveys in the Municipalities of Gonzaga, Gattaran, Lasam, Santa Ana, and Baggao (Cagayan Province), as well as fieldwork in the Municipalities of Cabagan, San Mariano, and Palanan (Isabela Province), combined with all available historical museum records, suggest this region is quite diverse. Our new data indicate that at least 101 species are present (29 amphibians, 30 lizards, 35 snakes, two freshwater turtles, three marine turtles, and two crocodilians) and now represented with well-documented records and/or voucher specimens, confirmed in institutional biodiversity repositories. A high percentage of Philippine endemic species constitute the local fauna (approximately 70%). The results of this and other recent studies signify that the herpetological diversity of the northern Philippines is far more diverse than previously imagined. Thirty-eight percent of our recorded species are associated with unresolved taxonomic issues (suspected new species or species complexes in need of taxonomic partitioning). This suggests that despite past and present efforts to comprehensively characterize the fauna, the herpetological biodiversity of the northern Philippines is still substantially underestimated and warranting of further study.

  8. The amphibians and reptiles of Luzon Island, Philippines, VIII: the herpetofauna of Cagayan and Isabela Provinces, northern Sierra Madre Mountain Range

    Directory of Open Access Journals (Sweden)

    Rafe Brown

    2013-02-01

    Full Text Available We provide the first report on the herpetological biodiversity (amphibians and reptiles of the northern Sierra Madre Mountain Range (Cagayan and Isabela provinces, northeast Luzon Island, Philippines. New data from extensive previously unpublished surveys in the Municipalities of Gonzaga, Gattaran, Lasam, Santa Ana, and Baggao (Cagayan Province, as well as fieldwork in the Municipalities of Cabagan, San Mariano, and Palanan (Isabela Province, combined with all available historical museum records, suggest this region is quite diverse. Our new data indicate that at least 101 species are present (29 amphibians, 30 lizards, 35 snakes, two freshwater turtles, three marine turtles, and two crocodilians and now represented with well-documented records and/or voucher specimens, confirmed in institutional biodiversity repositories. A high percentage of Philippine endemic species constitute the local fauna (approximately 70%. The results of this and other recent studies signify that the herpetological diversity of the northern Philippines is far more diverse than previously imagined. Thirty-eight percent of our recorded species are associated with unresolved taxonomic issues (suspected new species or species complexes in need of taxonomic partitioning. This suggests that despite past and present efforts to comprehensively characterize the fauna, the herpetological biodiversity of the northern Philippines is still substantially underestimated and warranting of further study.

  9. Magnetic signature of river sediments drained into the southern and eastern part of the South China Sea (Malay Peninsula, Sumatra, Borneo, Luzon and Taiwan)

    Science.gov (United States)

    Kissel, Catherine; Liu, Zhifei; Li, Jinhua; Wandres, Camille

    2017-01-01

    Magnetic properties of 22 river samples collected in the Malay Peninsula, Sumatra, Borneo, Luzon and Taiwan have been investigated in order to magnetically characterize the sediments drained and deposited into the South China Sea. The geological formations as well as the present climatic conditions are different from one region to another. Laboratory analyses include low-field magnetic susceptibility, anhysteretic (ARM) and isothermal (IRM) remanent magnetizations acquisition and decay, back-field acquisition, thermal demagnetization of three-axes IRM, hysteresis cycles and low-temperature magnetic measurements. The magnetic properties indicate that the sediments are a mixture of hematite, magnetite and pyrrhotite in different proportions depending on the region. Combined with results previously reported for the three main Asian rivers (Pearl, Red and Mekong rivers), the new data indicate that, in general, hematite-rich sediments are delivered to the southern basin of the South China Sea while the northern basin is fed with magnetite and pyrrhotite-rich sediments. In addition to this general picture, some variability is observed at smaller geographic scales. Indeed, the magnetic assemblages are closely related to the geology of the various catchments while clay minerals, previously reported for the same samples, are more representative of the climatic conditions under which the parent rocks have evolved within each catchment. The magnetic fraction, now well characterized in the main river sediments drained into the South China Sea, can be used as a tracer for changes in precipitation on land and in oceanic water mass transport and exchange.

  10. Strait of Gibraltar, Perspective with Landsat Image Overlay

    Science.gov (United States)

    2003-01-01

    This perspective view shows the Strait of Gibraltar, which is the entrance to the Mediterranean Sea from the Atlantic Ocean. Europe (Spain) is on the left. Africa (Morocco) is on the right. The Rock of Gibraltar, administered by Great Britain, is the peninsula in the back left.The Strait of Gibraltar is the only natural gap in the topographic barriers that separate the Mediterranean Sea from the world's oceans. The Sea is about 3700 kilometers (2300 miles) long and covers about 2.5 million square kilometers (one million square miles), while the Strait is only about 13 kilometers (8 miles) wide. Sediment samples from the bottom of the Mediterranean Sea that include evaporite minerals, soils, and fossil plants show that about five million years ago the Strait was topographically blocked and the Sea had evaporated into a deep basin far lower in elevation than the oceans. Consequent changes in the world's hydrologic cycle, including effects upon ocean salinity, likely led to more ice formation in polar regions and more reflection of sunlight back to space, resulting in a cooler global climate at that time. Today, topography plays a key role in our regional climate patterns. But through Earth history, topographic change, even perhaps over areas as small as 13 kilometers across, has also affected the global climate.This image was generated from a Landsat satellite image draped over an elevation model produced by the Shuttle Radar Topography Mission (SRTM). The view is eastward with a 3-times vertical exaggeration to enhance topographic expression. Natural colors of the scene (green vegetation, blue water, brown soil, white beaches) are enhanced by image processing, inclusion of some infrared reflectance (as green) to highlight the vegetation pattern, and inclusion of shading of the elevation model to further highlight the topographic features.Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter (99-feet

  11. Analysis of upwelling event in Southern Makassar Strait

    Science.gov (United States)

    Utama, F. G.; Atmadipoera, A. S.; Purba, M.; Sudjono, E. H.; Zuraida, R.

    2017-01-01

    The southeast monsoon (SEM) winds which blow in southern Makassar Strait, generate the coastal upwelling phenomenon. The wind data for one year, which is equipped with CTD data from MAJAFLOX cruise results, is used to analyze the phenomenon of upwelling in this region. During the SEM 2015 occurrence, the southeasterly winds speed were in average of 6 m/s, while the highest speed appeared in August and September. Using the Ekman theory’s analysis of upwelling during this monsoon period, we could estimate the Ekman transport was about 8.50 m2/s toward offshore (to the Southwest direction); the upwelled water, occurred from deeper layer, started from the coastal area with vertical velocity was about 6.87 x 10-5 m/s – 7.84 x 10-5 m/s; and The Ekman layer depth in the upwelling region was approximately 60 m and these were good agreement with CTD observation result.

  12. Fram Strait Spring Ice Export and September Arctic Sea Ice

    Science.gov (United States)

    Smedsrud, Lars H.; Halvorsen, Mari H.; Stroeve, Julienne; Zhang, Rong; Kloster, Kjell

    2016-04-01

    The Arctic Basin exports between 600 000 - 1 million km² of it's sea ice cover southwards through Fram Strait each year, comparing to about 10% of the ice covered area inside the basin. During winter ice export results in growth of new and relatively thin ice inside the basin, while during summer or spring export contributes directly to open water further north. A new updated time series from 1935 to 2014 of Fram Strait sea ice area export shows that the long-term annual mean export is about 880,000 km², with large annual and decadal variability and no long-term trend over the past 80 years. Nevertheless, the last decade has witnessed increased annual ice export, with several years having annual ice export exceed 1 million km². Evaluating the trend onwards from 1979, when satellite based sea ice coverage became more readily available, reveals an increase in annual export of about +6% per decade. This increase is caused by higher southward ice drift speeds due to stronger southward geostrophic winds, largely explained by increasing surface pressure over Greenland. Spring and summer area export increased more (+11% per decade) than in autumn and winter. Contrary to the last decade the 1950 - 1970 period had low export during spring and summer, and mid-September sea ice extent was consistently higher than both before and after these decades. We thus find that export anomalies during spring have a clear influence on the following September sea ice extent in general, and that for the recent decade the export may be partially responsible for the accelerating decline in Arctic sea ice extent.

  13. Wind forcing of salinity anomalies in the Denmark Strait overflow

    Directory of Open Access Journals (Sweden)

    S. Hall

    2011-06-01

    Full Text Available The overflow of dense water from the Nordic Seas to the North Atlantic through Denmark Strait is an important part of the global thermohaline circulation. The salinity of the overflow plume has been measured by an array of current meters across the continental slope off the coast of Angmagssalik, southeast Greenland since September 1998. During 2004 the salinity of the overflow plume changed dramatically, with the entire width of the array (70 km freshening between January 2004 and July 2004, with a significant negative salinity anomaly of about 0.06 in May. The event in May represents a fresh anomaly of over 3 standard deviations from the mean since recording began in 1998. We show that the OCCAM 1/12° Ocean General Circulation Model not only reproduces the 2004 freshening event (r=0.96, p<0.01, but also correlates well with salinity observations over a previous 6 year period (r=0.54, p<0.01. Consequently the physical processes causing the 2004 anomaly and prior variability in salinity are investigated using the model output. Our results reject the hypotheses that the anomaly is caused by processes occurring between the overflow sill and the moorings, or by an increase in upstream net freshwater input. Instead, we show that the 2004 salinity anomaly is caused by an increase in volume flux of low salinity water, with a potential density greater than 27.60 kg m−3, flowing towards the Denmark Strait sill in the East Greenland Current. This is caused by an increase of southward wind stress upstream of the sill at around 75° N 20° W four and a half months earlier, and an associated spin-up of the Greenland Sea Gyre.

  14. The vulnerability of the Strait of Georgia (Canada) to future hypoxia and ocean acidification

    Science.gov (United States)

    Ianson, Debby; Allen, Susan; Moore-Maley, Ben; Haigh, Rowan; Johannessen, Sophia; Macdonald, Robie; Krogh, Jeremy; Simpson, Eleanor; Kohfeld, Karen; Hamme, Roberta

    2016-04-01

    The Canadian Pacific coast is filled with fjords and islands. Circulation in the region is dynamic, so that large changes in acidity (pH) and oxygen may occur both in space and time. The Strait of Georgia (Canada) is a large (200 X 30 km) semi-enclosed basin, that has relatively low pH with respect to the adjacent outer coast and yet hosts a lucrative aquaculture industry. On the other hand this region is relatively well oxygenated due to gas exchange in the turbulent (tidal) flow in the narrow Straits with sills connecting it with the outer coast. We investigate the role that this intense gas exchange plays in protecting the Strait of Georgia from future hypoxia and ocean acidification. Finally, we contrast surface water properties (including dissolved inorganic carbon and total alkalinity) measured on large ships with those measured nearshore and at shore-based aquaculture sites within the Strait.

  15. Cultural safety and maternity care for Aboriginal and Torres Strait Islander Australians.

    Science.gov (United States)

    Kruske, Sue; Kildea, Sue; Barclay, Lesley

    2006-09-01

    To discuss cultural safety and critique the provision of culturally appropriate maternity services to remote Aboriginal and Torres Strait Islander women in Australia. The literature and policies around 'culture' and 'cultural safety' are discussed and applied to the provision of maternity services to Aboriginal and Torres Strait Islander women in remote areas of Australia. The current provision of maternity services to Aboriginal and Torres Strait Islander women, particularly those living in remote Australia, appears largely inadequate. The provision of culturally safe maternity care requires health system reform at all levels including: the individual practitioner response; the educational preparation of practitioners; the delivery of maternity services and the development of policy at local, state and national level. This paper considers the changes that can be made from the individual practitioner through to the design and implementation of maternity services. Cultural safety provides a useful framework to improve the delivery of maternity services to remote Aboriginal and Torres Strait Islander women and their families.

  16. Gravity cores from San Pablo Bay and Carquinez Strait, San Francisco Bay, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data release contains information on gravity cores that were collected by the U.S. Geological Survey in the area of San Pablo Bay and Carquinez Strait,...

  17. Seasonal and interannual variability of the water exchange in the Turkish Straits System estimated by modelling

    Directory of Open Access Journals (Sweden)

    V. MADERICH

    2015-07-01

    Full Text Available A chain of simple linked models is used to simulate the seasonal and interannual variability of the Turkish Straits System. This chain includes two-layer hydraulic models of the Bosphorus and Dardanelles straits simulating the exchange in terms of level and density difference along each strait, and a one-dimensional area averaged layered model of the Marmara Sea. The chain of models is complemented also by the similar layered model of the Black Sea proper and by a one-layer Azov Sea model with the Kerch Strait. This linked chain of models is used to study the seasonal and interannual variability of the system in the period 1970-2009. The salinity of the Black Sea water flowing into the Aegean Sea increases by approximately 1.7 times through entrainment from the lower layer. The flow entering into the lower layer of the Dardanelles Strait from the Aegean Sea is reduced by nearly 80% when it reaches the Black Sea. In the seasonal scale, a maximal transport in the upper layer and minimal transport in the bottom layer are during winter/spring for the Bosphorus and in spring for the Dardanelles Strait, whereas minimal transport in upper layer and maximal undercurrent are during the summer for the Bosphorus Strait and autumn for the Dardanelles Strait. The increase of freshwater flux into the Black Sea in interannual time scales (41 m3s-1 per year is accompanied by a more than twofold growth of the Dardanelles outflow to the North Aegean (102 m3s-1 per year.

  18. Seasonally Resolved Surface Water (delta)14C Variability in the Lombok Strait: A Coralline Perspective

    Energy Technology Data Exchange (ETDEWEB)

    Guilderson, T P; Fallon, S J; Moore, M D; Schrag, D P; Charles, C D

    2008-04-23

    We have explored surface water mixing in the Lombok Strait through a {approx}bimonthly resolved surface water {Delta}{sup 14}C time-series reconstructed from a coral in the Lombok Strait that spans 1937 through 1990. The prebomb surface water {Delta}{sup 14}C average is -60.5{per_thousand} and individual samples range from -72{per_thousand} to 134{per_thousand}. The annual average post-bomb maximum occurs in 1973 and is 122{per_thousand}. The timing of the post-bomb maximum is consistent with a primary subtropical source for the surface waters in the Indonesian Seas. During the post-bomb period the coral records regular seasonal cycles of 5-20{per_thousand}. Seasonal high {Delta}{sup 14}C occur during March-May (warm, low salinity), and low {Delta}{sup 14}C occur in September (cool, higher salinity). The {Delta}{sup 14}C seasonality is coherent and in phase with the seasonal {Delta}{sup 14}C cycle observed in Makassar Strait. We estimate the influence of high {Delta}{sup 14}C Makassar Strait (North Pacific) water flowing through the Lombok Strait using a two endmember mixing model and the seasonal extremes observed at the two sites. The percentage of Makassar Strait water varies between 16 and 70%, and between 1955 and 1990 it averages 40%. During La Nina events there is a higher percentage of Makassar Strait (high {Delta}{sup 14}C) water in the Lombok Strait.

  19. Physical characteristic of brown algae (Phaeophyta) from madura strait as irreversible hydrocolloid impression material

    OpenAIRE

    Prihartini Widiyanti; Siswanto Siswanto

    2012-01-01

    Background: Brown algae is a raw material for producing natrium alginates. One type of brown algae is Sargassum sp, a member of Phaeophyta division. Sargassum sp could be found in Madura strait Indonesia. Natrium alginate can be extracted from Sargassum sp. The demand of alginate in Indonesia is mainly fulfilled from abroad, meanwhile Sargassum sp is abundantly available. Purpose: The purpose of study were to explore the potency of brown alga Sargassum sp from Madura strait as hydrocolloid im...

  20. The importance of sub-mesoscale processes for the exchange of properties through the Strait of Gibraltar

    Science.gov (United States)

    Bruno, M.; Chioua, J.; Romero, J.; Vázquez, A.; Macías, D.; Dastis, C.; Ramírez-Romero, E.; Echevarria, F.; Reyes, J.; García, C. M.

    2013-09-01

    This article presents a detailed analysis of the sub-mesoscale transport processes in the Strait of Gibraltar. The interest is focussed on the Camarinal Sill region, and special attention is paid to the across-strait transport processes, the divergences and convergences in the central zone, and the small-scale circulation patterns along the northern coastal margin. The analysis is based on high-resolution (7 m) SST images acquired by an air-borne hyper-spectral scanner, and has been complemented with a rhodamine-release experiment, continuous thermo-salinograph records, acoustic Doppler current (ADCP) profiles from both moorings and vessel-mounted experiments, and numerical modelling. It is deduced from the analysis that the coupling between the upwelling processes, induced by the internal tide and the generation of large-amplitude internal waves, and the cyclonic eddies formed on the coastal margin, seems to be the mechanism that explains the chlorophyll maxima frequently found on the coastal margin of the studied area. Further, as a consequence of the small-scale patterns of circulation induced by the internal waves, the suspended substances are displaced from the coastal margins toward the central zones and later are carried by the westward current toward the convergence zones created by the internal waves, where they may be retained and accumulate. Then, in the eastward phase of the tidal current over the Camarinal Sill, these nuclei of concentrated substances (nutrients, chlorophyll, and plankton) are transported toward the Alboran Sea, where they must contribute, in part, to the primary productivity there. High-resolution (7 m) SST images acquired by an Airborne Hyper-spectral Scanner (AHS) provided by the Spanish Institute of Aerospace Techniques (INTA). Measurements made along vessel transects crossing the studied zone, of current velocity and echo-intensity profiles acquired by ADCP, and sea surface temperature, salinity and released rhodamine (see Fig. 1

  1. Cropping Pattern Detection and Change Analysis in Central Luzon, Philippines Using Multi-Temporal MODIS Imagery and Artificial Neural Network Classifier

    Science.gov (United States)

    dela Torre, D. M.; Perez, G. J. P.

    2016-12-01

    Cropping practices in the Philippines has been intensifying with greater demand for food and agricultural supplies in view of an increasing population and advanced technologies for farming. This has not been monitored regularly using traditional methods but alternative methods using remote sensing has been promising yet underutilized. This study employed multi-temporal data from MODIS and neural network classifier to map annual land use in agricultural areas from 2001-2014 in Central Luzon, the primary rice growing area of the Philippines. Land use statistics derived from these maps were compared with historical El Nino events to examine how land area is affected by drought events. Fourteen maps of agricultural land use was produced, with the primary classes being single-cropping, double-cropping and perennial crops with secondary classes of forests, urban, bare, water and other classes. Primary classes were produced from the neural network classifier while secondary classes were derived from NDVI threshold masks. The overall accuracy for the 2014 map was 62.05% and a kappa statistic of 0.45. 155.56% increase in single-cropping systems from 2001 to 2014 was observed while double cropping systems decreased by 14.83%. Perennials increased by 76.21% while built-up areas decreased by 12.22% within the 14-year interval. There are several sources of error including mixed-pixels, scale-conversion problems and limited ground reference data. An analysis including El Niño events in 2004 and 2010 demonstrated that marginally irrigated areas that usually planted twice in a year resorted to single cropping, indicating that scarcity of water limited the intensification allowable in the area. Findings from this study can be used to predict future use of agricultural land in the country and also examine how farmlands have responded to climatic factors and stressors.

  2. A new species of limestone karst inhabiting forest frog, genus Platymantis (Amphibia: Anura: Ceratobatrachidae: subgenus Lupacolus) from southern Luzon Island, Philippines.

    Science.gov (United States)

    Brown, Rafe M; De Layola, Louise Abigail; Lorenzo, Antonio; Diesmos, Mae Lowe L; Diesmos, Arvin C

    2015-11-25

    We describe a new species of limestone karst dwelling forest frog of the genus Platymantis from the Quezon Protected Landscape in southeastern Luzon Island, Philippines. We assign Platymantis quezoni, sp. nov., to the diverse assemblage of terrestrial species in the Platymantis dorsalis Group, subgenus Lupacolus on the basis of its body size and proportions, only slightly expanded terminal discs of the fingers and toes, and its terrestrial microhabitat. The new species is distinguished from these and all other Philippine congeners by features of its external morphology, its restriction to a distinctive limestone karst microhabitat, and its advertisement call, which is unique among frogs of the family Ceratobatrachidae. Several distinguishing morphological characters include its moderate body size (22.1-33.9 mm SVL for 16 adult males and 32.4-39.7 mm SVL for five adult females), slightly expanded terminal discs of the fingers and toes, smooth skin with limited dermal tuberculation, and a dorsal color pattern of mottled tan to dark brown with black blotches. The new species is the sixth Philippine Platymantis known to occur exclusively on limestone karst substrates (previously known karst-obligate species include: P. bayani, P. biak, P. insulatus, P. paengi, and P. speleaus). Recently accelerated discovery of limestone karst anurans across the Philippines suggests that numerous additional species may await discovery on the hundreds of scattered karst formations throughout the archipelago. This possibility suggests that a major conservation priority in coming years will be to study, characterize, describe, and preserve the endemic species supported by this patchy, unique and imperiled type of forest ecosystem in the Philippines.

  3. Discussion in the Research on American History of Westward Development%美国西部开发史研究综述

    Institute of Scientific and Technical Information of China (English)

    王储; 蒋涛

    2012-01-01

    19世纪美国西部开发取得巨大成就,成为世界上对欠发达地区成功开发的典型。自上世纪90年代以来,我国学术界充分认识到研究美国西部开发史的现实意义,对该课题进行了卓有成效的探讨,取得了较为丰硕的成果,主要集中在美国西部开发中的土地政策、交通革命和城市化等领域。本文对这些成果加以综述,较为完整地描述了我国学术界对美国西部开发史的研究现状。%The western part of the United States has made a great progress in the development in 19th century known as "the westward expansion". This became an ideal model and was subsequ ently applied to the exploration of the undeveloped areas. Since the 1990s, scholars in China have increasingly recognized the international significance of the history of America~ development of the West. By the highly effective discussion of this study, scholars have a- chieved a lot which focus on the field of land policy, transportation revolution and urbanization under the development of western regions in America. In this paper, the author offers an deep review of these advancements. This is followed by a discussion of the current developments in the research of Chinese academics and their analysis of the American his- tory of westward development.

  4. 浅析“一带一路”与中国向西开放%One Belt One Road Initiative and China's Westward Opening up

    Institute of Scientific and Technical Information of China (English)

    黄勇

    2015-01-01

    To open westward has practical significance for China in paving a shortcut way for trades between China and neighboring coun-tries in Asia and Europe, facilitating trade and investment, realizing transnational productivity cooperation and upgrade of equipment man-ufacturing industry, and safeguarding a smooth energy passageway. To propel the initiative of One Belt One Road is an important content of China's 13th five year plan. Through the joint development, China is going to advance regional cooperation, fueling the strategic mutual trust, economic and trade cooperation and cultural and educational exchange between countries along the line. Finally, a free trade zone for the countries will be built, which is China's key strategy for opening up westward.%向西开放,对打通中国与亚欧邻国贸易的快捷通道、促进贸易投资便利化、实现跨国产能合作与装备制造业升级、保障中国的能源通道的畅通具有现实意义。推进一带一路是十三五规划的重要内容,中国将通过共建“一带一路”推动区域合作,努力达成沿线国家战略互信、经贸合作、人文交流,最终会整合出一带一路沿线国家自贸区,这是中国向西开放的重大战略。

  5. Characteristics of Marine Recreational Fishing in the anakkale Strait (Turkey

    Directory of Open Access Journals (Sweden)

    V. UNAL

    2012-12-01

    Full Text Available The economic and harvest impacts of Marine Recreational Fishing (MRF in Çanakkale Strait were analysed along with fishing policy, sociology and habits of fishers. Data sources included field survey data carried out along the entire length of the Çanakkale strait and policy information gathered from published sources. MRF policy is commendable, even in the fishing tourism sector, and is better developed than that in many other European countries. In Çanakkale, 9.9% of the population is recreational fishers. Recreational fishers are typically men (90%, primarily those between the ages of 25 and 49 yrs. The occupation of the recreational fishers ranged from self-employed (28%, students (28%, retired persons (22% and public employees (15%, to currently-unemployed persons (7%. An analysis of diel behaviour showed that most recreational fishers preferred fishing during the day (56.1%, while the evening was the next most preferred time for fishing (18%, followed by the night-time (9.8%, while a substantial number of recreational fishers (16.1% reported that they fished at any time of day. The most popular type of fishing was shore-based (68%, followed by boat-based (21%, and underwater fishing (11%. The mean daily fishing times were 6.07 h d-1, 6.18 h d-1 4.75 d-1 for boat-based, underwater and shore-based fishing, respectively. Summer and autumn were the preferred seasons for shore-based and underwater fishing, while autumn and winter were preferred for boat-based fishing. The highest Catch per Unit Effort (CPUE was observed for boat-based fishing (2.77 kg h-1, followed by underwater (0.97 kg h-1 and shore-based fishing (0.81 kg h-1. The catch composition included 51 species, though the catch composition of each fishing type was mostly comprised of only 3 or 4 species. The impact of the MRF harvest was high (30% of commercial fishing, particularly for bluefish (Pomatomus saltatrix and picarel (Spicara smaris species. The economic impact of MRF was

  6. Water, heat and salt transport through the Strait of Otranto

    Science.gov (United States)

    Yari, Sadegh; Gačić, Miroslav; Kovačević, Vedrana; Cardin, Vanessa

    2010-05-01

    The water, heat and salt transports through the Strait of Otranto are estimated applying direct method to historical current and hydrographical data (from December 94 through November 95). A variational inverse method based on a variational principle and a finite element solver is used to reconstruct the current, temperature and salinity fields across the Strait section from sparse measurements. The mean annual inflow and outflow water transport rates are estimated as 0.901±0.039 Sv and -0.939±0.315 Sv, respectively, and the net transport for the period of study is equal to -0.032±0.208 Sv. Thus, on a yearly time interval, the inflow and the outflow are practically compensated. The heat and salt transports due to advection process are estimated for five monthly periods, namely December 1994, February, May, August and November 1995. Considering these five periods representative of the seasonal cycle during the year, their average values show that there is a net heat advection into the Adriatic Sea on a yearly basis. The estimated value of advected heat and the corresponding error are 2.408±0.490 TW, which is equivalent to a heat gain of 17.37±3.53 W m-2 for the whole basin. This value is compared to the heat loss of -36±152 (std) W m-2 through the air-sea interface calculated by means of bulk formulas over the Adriatic Sea. The two values are expected to be balance each other in order to close the heat budget of the basin. The possible reasons for this difference to occur are discussed. On a yearly basis, the salt transport is estimated as an input of salt equal to 0.05×106 Kg s-1. The average annual fresh water budget is estimated as -0.002 Sv, equivalent to the mass of fresh water of 2.00×106Kg s-1 or to the level of 0.45 m yr-1 for the entire Adriatic Sea. The import of salt that is less than the gain of fresh water is in agreement with the fact that the Adriatic Sea is a dilution basin.

  7. Characteristics of Marine Recreational Fishing in the anakkale Strait (Turkey

    Directory of Open Access Journals (Sweden)

    V. UNAL

    2010-11-01

    Full Text Available The economic and harvest impacts of Marine Recreational Fishing (MRF in Çanakkale Strait were analysed along with fishing policy, sociology and habits of fishers. Data sources included field survey data carried out along the entire length of the Çanakkale strait and policy information gathered from published sources. MRF policy is commendable, even in the fishing tourism sector, and is better developed than that in many other European countries. In Çanakkale, 9.9% of the population is recreational fishers. Recreational fishers are typically men (90%, primarily those between the ages of 25 and 49 yrs. The occupation of the recreational fishers ranged from self-employed (28%, students (28%, retired persons (22% and public employees (15%, to currently-unemployed persons (7%. An analysis of diel behaviour showed that most recreational fishers preferred fishing during the day (56.1%, while the evening was the next most preferred time for fishing (18%, followed by the night-time (9.8%, while a substantial number of recreational fishers (16.1% reported that they fished at any time of day. The most popular type of fishing was shore-based (68%, followed by boat-based (21%, and underwater fishing (11%. The mean daily fishing times were 6.07 h d-1, 6.18 h d-1 4.75 d-1 for boat-based, underwater and shore-based fishing, respectively. Summer and autumn were the preferred seasons for shore-based and underwater fishing, while autumn and winter were preferred for boat-based fishing. The highest Catch per Unit Effort (CPUE was observed for boat-based fishing (2.77 kg h-1, followed by underwater (0.97 kg h-1 and shore-based fishing (0.81 kg h-1. The catch composition included 51 species, though the catch composition of each fishing type was mostly comprised of only 3 or 4 species. The impact of the MRF harvest was high (30% of commercial fishing, particularly for bluefish (Pomatomus saltatrix and picarel (Spicara smaris species. The economic impact of MRF was

  8. Eddies spatial variability at Makassar Strait – Flores Sea

    Science.gov (United States)

    Nuzula, F.; Syamsudin, M. L.; Yuliadi, L. P. S.; Purba, N. P.; Martono

    2017-01-01

    This study was aimed to get the distribution of eddies spatially and temporally from Makassar Waters (MW) to Flores Sea (FS), as well as its relations with the upwelling, the downwelling, and chlorophyll-a concentration. The study area extends from 115º–125º E to 2.5º–8º S. The datasets were consisted of monthly geostrophic currents, sea surface heights, sea surface temperatures, and chlorophyll-a from 2008 – 2012. The results showed that eddies which found at Makassar Strait (MS) has the highest diameter and speed of 255.3 km and 21.4 cm/s respectively, while at the southern MW has 266.4 km and 15.6 cm/s, and at FS has 182.04 km and 11.4 cm/s. From a total of 51 eddies found, the majority of eddies type was anticyclonic. At MS and FS, eddies formed along the year, whereas at southern MW were found missing in West Season. Moreover, the chlorophyll-a concentration was consistently higher at the eddies area. Even though, the correlation among eddies and the upwelling downwelling phenomena was not significantly as shown by sea surface temperatures value.

  9. Mixing and transformation in the Denmark Strait Overflow

    Science.gov (United States)

    Koszalka, Inga; Haine, Thomas; Magaldi, Marcello

    2014-05-01

    The Denmark Strait Overflow (DSO) is one of the major export routes for the dense waters from the Nordic Seas to the North Atlantic. However, the observations of the DSO are limited to a few locations and poorly resolve mixing processes that transform the dense waters and hence influence propagation of hydrographic signals from the Arctic to the Atlantic. We use a high resolution circulation model to diagnose mixing processes involving the DSO in the Irminger Basin. We focus on mesoscale (10-100km) processes, the most prominent being dense cyclonic boluses making up the overflow plume. The subgrid turbulent processes are represented by the K-profile parameterization. We map the horizontal and vertical eddy diffusivities derived from Lagrangian particles, the model vertical mixing coefficient and eddy fluxes. Our results are consistent with observations suggesting enhanced vertical mixing during the initial (~ 200km) descent of the dense plume and increasing importance of horizontal mixing downstream. The model also shows enhanced mixing along the dense water pathways in the Kangerdlugssuaq Trough on the East Greenland Shelf involving fresh Polar Waters. However, the most intense mixing is induced by mesoscale boluses of dense water cascading down the sill and the associated internal wave field. Frequent occurrence of a neutrally stratified mixed layer in the dense plume poses a challenge for the turbulent scheme of the model. We advocate for an observational campaign that would corroborate these results and help develop novel parametrizations of the vertical mixing processes in the DSO.

  10. Legally invisible: stewardship for Aboriginal and Torres Strait Islander health.

    Science.gov (United States)

    Howse, Genevieve; Dwyer, Judith

    2016-04-01

    The need to improve access to good health care for Aboriginal and Torres Strait Islander people has been the subject of policy debate for decades, but progress is hampered by complex policy and administrative arrangements and lack of clarity about the responsibilities of governments. This study aimed to identify the current legal basis of those responsibilities and define options available to Australian governments to enact enduring responsibility for Aboriginal health care. This study used a framework for public health law research and conducted a mapping study to examine the current legal underpinnings for stewardship and governance for Aboriginal health and health care. More than 200 pieces of health legislation were analysed in the context of the common and statutory law and health policy goals. Very little specific recognition of the needs of Aboriginal people was found, and nothing that creates responsibility for stewardship and governance. The continuing absence of a legislative framework to address and protect Aboriginal health can be traced back to the founding doctrine of terra nullius (unoccupied land). We considered the results applying both a human rights perspective and the perspective of therapeutic jurisprudence. We suggest that national law for health stewardship would provide a strong foundation for progress, and should itself be based on recognition of Australia's First Peoples in the Australian Constitution, as is currently proposed. © 2015 The Authors.

  11. Tide at the eastern section of the Strait of Gibraltar

    Science.gov (United States)

    Lafuente, Jesús Garcia; Vargas, Juan Miguel; Plaza, Francisco; Sarhan, Tarek; Candela, Julio; Bascheck, Burkard

    2000-06-01

    From October 1995 to April 1996, three mooring lines were deployed at the eastern entrance of the Strait of Gibraltar. The spatial coverage of the mooring array allows for a good description of the tides. They exhibit a dominant semidiurnal nature and a noticeable baroclinic structure that matches the one of the mean exchange. Tidal currents in the upper layer are irregular and usually too weak to reverse the mean upper layer flow that keeps on flowing east. Lower layer flow reverses with semidiurnal periodicity because of the smallness of the mean flow and the appreciable amplitude of the regular semidiurnal oscillation of tidal currents in this layer. Tidal transports can be satisfactorily compared with previous estimates of Bryden et al. [1994] if we allow for strong internal divergences associated with the internal tide. No significant eddy flux of water transport (tidal rectification) is observed at the eastern section, contrary to the almost 50% of the total layer transport found by Bryden et al. [1994] in Camarinal Sill section. Time-dependent hydraulic theory provides a good scenario for interpreting these two independent sets of observations despite the fact that the composite Froude number does not reach the critical values predicted in the hydraulic models most of the time.

  12. Analysis of turbulent mixing in Dewakang Sill, Southern Makassar Strait

    Science.gov (United States)

    Risko; Atmadipoera, A. S.; Jaya, I.; Sudjono, E. H.

    2017-01-01

    Dewakang Sill is located in southern Makassar Strait, conveying major path of Indonesian Throughflow (ITF), as a confluence region of different water masses, such as salty Pacific water and fresh Java Sea water. Its depth is about 680 m which blocks the ITF flow below this depth into Flores Sea. This research aimed to estimate turbulent mixing in the Dewakang Sill by applying Thorpe analysis using 24 hours “yoyo” CTD data sets, acquired from MAJAFLOX Cruise in August 2015. The results showed that stratification of water masses is dominated by Pacific water origin. Those are North Pacific Subtropical thermocline and Intermediate water masses. Mean dissipation of turbulent kinetic energy (ɛ) and turbulent vertical diffusivity (Kρ ) value in the Dewakang Sill are of O(1.08 × 10‑6)Wkg‑1, and O(2.84 × 10‑4) m2s‑1 respectively. High correlation between epsilon and internal waves oscillation suggested that internal tidal waves activities are the major forcing for turbulent mixing in the study area.

  13. Abundance of walruses in Eastern Baffin Bay and Davis Strait

    Directory of Open Access Journals (Sweden)

    Mads Peter Heide-Jørgensen

    2014-12-01

    Full Text Available Walruses (Odobenus rosmarus are exploited for subsistence purposes in West Greenland. However, current information about the abundance of walruses subject to harvest in eastern Baffin Bay subject to harvest has been unavailable despite being critical for maintaining sustainable catch levels. Three visual aerial surveys were conducted in 2006 (21 March to 19 April 2006, 2008 (3 to 12 April and 2012 (24 March to 14 April to estimate the number of walruses on the wintering grounds in eastern Baffin Bay and Davis Strait. Data on the fraction of walruses that were submerged below a 2m detection threshold during the surveys were obtained from 24 walruses instrumented with satellite-linked-time-depth-recorders in northern Baffin Bay in May-June 2010-2012. An availability correction factor was estimated at 36.5% (cv=0.08 after filtering of data for an observed drift of the pressure transducer of more than 2.5 m. The surveys resulted in walrus abundance estimates that were corrected for walruses submerged below a detection threshold and for walruses that were missed by the observers. The estimates of abundance were 1,105 (cv=0.31, 95% CI 610-2,002 in 2006, 1,137 (0.48, 468-2,758 in 2008 and 1,408 (0.22, 922-2,150 in 2012.

  14. 231Pa/230Th records of Arctic/Atlantic interchange in Fram Strait

    Science.gov (United States)

    Hoffmann, S. S.; McDermott, K. J.; McManus, J. F.; Mukasa, S. B.

    2014-12-01

    Fram Strait, the Arctic Ocean's only deep passage for exchange with lower latitude oceans, today serves as a conduit for waters flowing north into the Arctic Ocean and south into the Atlantic. Reconstruction of circulation patterns and strength at depth in the strait can help to clarify the history of Arctic/Atlantic deep water exchange and Arctic contributions to global meridional overturning circulation. We will present new sedimentary measurements of radioisotopes 231Pa and 230Th to provide information on this exchange in the past and its relationship to sedimentation and climatic events. Coretop and downcore 231Pa/230Th ratios from Arctic sediments indicate that 231Pa has been exported from the central Arctic basin throughout the Holocene and deglaciation. Fram Strait represents a possible sink for this "missing" 231Pa. Preliminary results from ODP Holes 908A and 909A, at 1274 m and 2519 m water depths respectively in the central strait, suggest that ratios in this region during the Holocene have varied between ~0.106 (above the 231Pa/230Th production ratio of 0.093 in seawater, indicating net import of 231Pa)and ~0.055 (well below the production ratio, indicating net export of 231Pa). Further measurements in cores from the Greenland and Svalbard continental slopes will give a fuller regional picture of 231Pa deposition and transport across the strait.

  15. Risk Assessment in the Istanbul Strait Using Black Sea MOU Port State Control Inspections

    Directory of Open Access Journals (Sweden)

    Esma Gül Emecen Kara

    2016-04-01

    Full Text Available The Istanbul Strait has intense maritime traffic while, at the same time, it poses significant navigational challenges. Due to these properties, there is always a high risk arising from maritime shipping in this region. Especially, substandard ships threaten life, as well as the marine environment. In this aspect, Black Sea Memorandum of Understanding (MOU Port State Control Inspections are important for maritime safety in the Istanbul Strait, because they directly reflect the performance of ships passing through the Istanbul Strait. Stringent and effective inspections assist in the enhancement of navigation safety and help to develop sustainable environment management. In this context, this study aims to assess maritime safety for the Strait region concerning passing flag states. Firstly, to assess the performance of flag states in general, the Black Sea MOU Black-Grey-White lists were generated for the period 2004–2014 and the change in the performance of these flags was examined. Secondly, the risk level of each flag state passing from the Strait region was determined using the method of weighted points based on the Black-Grey-White List, deficiency index level, casualty index level, and passing index level.

  16. Geophysical study of a crustal section across the Straits of Messina

    Directory of Open Access Journals (Sweden)

    D. SCHIAVONE

    1979-06-01

    Full Text Available This paper presents the results of geophysical researches which can
    contribute to a better definition of a structural model for the Straits of
    Messina. It is part of the seismological researches, particularly of seismic
    microzonation, which are being carried out in the area of the Straits.
    The crustal model proposed for a cross section of the Straits has
    been based, for its upper part, on data of dipole electrical soundings
    and, for its deeper structures, on seismological observations and on their
    comparison with data of active seismic.
    the Graben structure of the Straits recently proposed, with the Calabrian
    The obtained section emphasize, with some detail in the upper part, block structurally in a higher position than the Sicilian one. Such structural
    character has been put in evidence by refraction seismic sections
    to a depth of about 18 Km.
    The correlation between the structures of the area surrounding the
    Straits and the hypocentral distribution for the heaviest earthquakes with
    focus in the area is pointed out.

  17. Is the Gibraltar strait a barrier to gene flow for the bat Myotis myotis (Chiroptera: Vespertilionidae)?

    Science.gov (United States)

    Castella, V; Ruedi, M; Excoffier, L; Ibáñez, C; Arlettaz, R; Hausser, J

    2000-11-01

    Because of their role in limiting gene flow, geographical barriers like mountains or seas often coincide with intraspecific genetic discontinuities. Although the Strait of Gibraltar represents such a potential barrier for both plants and animals, few studies have been conducted on its impact on gene flow. Here we test this effect on a bat species (Myotis myotis) which is apparently distributed on both sides of the strait. Six colonies of 20 Myotis myotis each were sampled in southern Spain and northern Morocco along a linear transect of 1350 km. Results based on six nuclear microsatellite loci reveal no significant population structure within regions, but a complete isolation between bats sampled on each side of the strait. Variability at 600 bp of a mitochondrial gene (cytochrome b) confirms the existence of two genetically distinct and perfectly segregating clades, which diverged several million years ago. Despite the narrowness of the Gibraltar Strait (14 km), these molecular data suggest that neither males, nor females from either region have ever reproduced on the opposite side of the strait. Comparisons of molecular divergence with bats from a closely related species (M. blythii) suggest that the North African clade is possibly a distinct taxon warranting full species rank. We provisionally refer to it as Myotis cf punicus Felten 1977, but a definitive systematic understanding of the whole Mouse-eared bat species complex awaits further genetic sampling, especially in the Eastern Mediterranean areas.

  18. Moho Depth Derived from Gravity Data in the Taiwan Strait Area

    Directory of Open Access Journals (Sweden)

    Hsien-Hsiang Hsieh

    2010-01-01

    Full Text Available We have constructed are gional Bouguer gravity anomaly map using marine and land data from Tai wan and the Chinese province of Fuchien, as well as SEASAT altimetry-de rived gravity data for the Tai wan Strait and its surrounding area. The map shows isogals trending generally in a NE-SW direction, conforming with the over all shallower geo logical strike of the strait. Removing gravity effects generated by the water layer and seafloor to pography, the regional Bouguer gravity anomaly is obtained, reflecting the subsurface structure. Moho depth is then computed by the Parker-Oldenburg iterative method from the regional Bouguer gravity data set. Over the strait area, the geometry of the Moho relief is smooth with an average depth of about 30 km, except for the Penghu up lift. Moho depth is shallower in the Taiwan Strait and thickens to ward both sides of the strait. The relatively shallower Moho depth, reaching up to 28 km, is convex up ward underneath the Penghu uplift.

  19. Moho Depth Derived from Gravity Data in the Taiwan Strait Area

    Directory of Open Access Journals (Sweden)

    Hsien-Hsiang Hsieh

    2010-01-01

    Full Text Available We have constructed are gional Bouguer gravity anomaly map using marine and land data from Tai wan and the Chinese province of Fuchien, as well as SEASAT altimetry-de rived gravity data for the Tai wan Strait and its surrounding area. The map shows isogals trending generally in a NE-SW direction, conforming with the over all shallower geo logical strike of the strait. Removing gravity effects generated by the water layer and seafloor to pography, the regional Bouguer gravity anomaly is obtained, reflecting the subsurface structure. Moho depth is then computed by the Parker-Oldenburg iterative method from the regional Bouguer gravity data set. Over the strait area, the geometry of the Moho relief is smooth with an average depth of about 30 km, except for the Penghu up lift. Moho depth is shallower in the Taiwan Strait and thickens to ward both sides of the strait. The relatively shallower Moho depth, reaching up to 28 km, is convex up ward underneath the Penghu uplift.

  20. Species composition and distribution of marine nematode community in the North Taiwan Strait

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Marine free-living nematodes were investigated at 13 sampling stations divided into three transects in the northern Taiwan Strait in February 1998. One hundred species of marine nematodes belonging to 91 Genera 28 Families 3 Orders were identified and were first recorded in the northern Taiwan Strait. The dominant species were Vasostoma sp., Sabatieria sp. 1, Linhystera sp. 1, Spilophorella sp., Daptonema sp., Halalaimus sp. and Dorylaimopsis variabilis. Their mean densities were all over 4 950 ind./m2. According to mean density at transects, marine nematode density decreased from coastal Weitou to off Minjiang Estuary, which was similar to polychaete distribution in the northern Taiwan Strait. The selective deposit feeder (1A) was the dominant food type of marine nematodes in the northern Taiwan Strait, but non-selective deposit feeders (1B) and epigrowth feeders (2A) occupied high proportion, indicating diverse feeding types of marine nematodes in the northern Taiwan Strait.Some environmental factors such as currents are discussed.

  1. Transport estimates in the Strait of Gibraltar with a tidal inverse model

    Science.gov (United States)

    Baschek, Burkard; Send, Uwe; Lafuente, Jesus Garcia; Candela, Julio

    2001-12-01

    To estimate the volume transport through the Strait of Gibraltar and to study the spatial structure of the time-variable flow, a varying number of current meter moorings were maintained at the eastern entrance of the strait between October 1994 and April 1998, and was complemented with intensive shipboard measurements during the European Union project Canary Island Azores Gibraltar Experiment (CANIGO). A tidal inverse model is used to merge these data sets in order to investigate the flow at the eastern entrance of the strait. The two-dimensional structure of the tidal flow was described by simple analytical functions. Harmonics with the seven most important tidal frequencies were used as temporal functions. With this model, the tidal currents can be predicted for any time and location at the eastern entrance of the strait, and more than 92% of the variance of the lower layer flow is explained. It was used to remove the tidal currents from the individual measurements and to calculate the mean flow through the strait from the residuals. Combined with a similar inverse model for determining the depth of the interface between Mediterranean and Atlantic water, the volume transport was estimated to be 0.81±0.07 Sv for the upper layer and -0.76±0.07 Sv for the lower layer. The correlation of the tidal currents and the fluctuations of the interface accounts for ˜7% of the transport at the eastern entrance.

  2. Effective communication tools to engage Torres Strait Islanders in scientific research

    Science.gov (United States)

    Jones, A.; Barnett, B.; Williams, A. J.; Grayson, J.; Busilacchi, S.; Duckworth, A.; Evans-Illidge, E.; Begg, G. A.; Murchie, C. D.

    2008-09-01

    Often, research activities in Torres Strait have not delivered full benefit to Torres Strait Islanders due to a lack of consultation, ineffectual communication of research information and lack of empathy for the needs of Islander communities. As for other stakeholder groups, integration of Islanders into the research process through practical involvement in research may overcome these problems. Three case studies from research projects conducted in Torres Strait are discussed to highlight a variety of communication and engagement activities carried out by non-Indigenous researchers. How these communication and extension activities facilitate collaboration between Torres Strait Islander and non-Indigenous researchers provides insight in the importance of these activities to the relative success of research projects. The benefits for Islanders in collaborating with researchers may be: improved understanding of the research and how it contributes to natural resource management; a sense of control in future management decisions; a greater likelihood of successful self-regulatory management systems; enhanced skills; and increased employment opportunities. The potential benefits for researchers are enhanced support for research projects resulting in increased access to data and logistic support that may ultimately impact the successful completion of projects. Such an approach will require researchers to take time to develop relationships with Torres Strait Islanders, effectively involve Islanders in research on an equitable basis and be flexible. This will ultimately require funding organisations to recognise the importance of such activities in research proposals and provide support through sufficient funding to enable these activities to be carried out.

  3. Australia's Efforts to Improve Food Security for Aboriginal and Torres Strait Islander Peoples.

    Science.gov (United States)

    Davy, Deanna

    2016-12-01

    Australia is a wealthy country; however, available evidence suggests that food security among Aboriginal and Torres Strait Islander peoples has not yet been achieved. Aboriginal and Torres Strait Islander peoples living in remote, regional, and urban parts of Australia experience food insecurity for a number of reasons that usually include low income and a lack of access to affordable and healthy food. The much higher rate of illness and disease that this population experiences compared to non-indigenous Australians is directly related to food insecurity. This paper examines the food insecurity among Aboriginal and Torres Strait Islander peoples and recent Australian government efforts to combat this problem. The paper first considers what constitutes a human rights-based approach to achieving food security. Second, it describes the food insecurity that currently exists among Aboriginal and Torres Strait Islander peoples across the three pillars of food access, food availability, and food use. Third, the paper critically examines recent and current Australian government policy aimed at improving food security. The paper concludes with some reflections regarding how the Australian government can improve its efforts to achieve food security for Aboriginal and Torres Strait Islander peoples.

  4. Study on respiratory electron transport system (ETS) of phytoplankton in Taiwan Strait and Xiamen Harbour

    Institute of Scientific and Technical Information of China (English)

    HUANG Bangqin; HONG Huasheng; XU Xiangzhong; LIU Yuan

    2005-01-01

    Phytoplankton respiratory electron transport system (P-ETS) activities were studied in two cruises in Taiwan Strait (Aug. 1997 and Feb. -Mar. 1998) and two cruises in Xiamen Harbour (Oct., 1997 and Apr.,1998). Results showed that P-ETS activity in the surface water of southern Taiwan Strait in summer was homogeneous [mean value of 0.106 μlO2/(L.h)], inhomogeneous in northern Taiwan Strait in winter. Variation of P-ETS activity in middle part of the Strait was not obvious between summer and winter. Mean P-ETS activity of Xiamen Harbour in autumn was 0.255 μlO2/(L.h) with a little higher value in Jiulong River estuary areas. In spring, P-ETS activity was more homogeneously distributed and the mean value was 1.076 μlO2/(L.h). P-ETS activity in spring was obviously higher than in autumn in Xiamen Harbour. Vertical distribution of P-ETS in Taiwan Strait was homogeneous at some stations in winter and in summer. An obvious daily variation of P-ETS activity was recorded at Stn 9837, high at midnight and low in the early morning. Significant correlation between P-ETS activity and Chl-a was observed. Results also showed that the ratio of estimated respiratory rate to photosynthetic rate varied seasonally, high in winter (0.41) and low in summer (0.12).

  5. IMPACT OF CLIMATE ANOMALY ON CATCH COMPOSITION OF NERITIC TUNA IN SUNDA STRAIT

    Directory of Open Access Journals (Sweden)

    Khairul Amri

    2013-12-01

    Full Text Available Tongkol komo/kawakawa (Euthynnus affinis and tenggiri (Scomberomerus guttatus are commonly caught by mini purseiners operated in Sunda Straits and landed in Labuan, West Java. This species inhabits coastal water and has preference staying in relatively warm water. Oceanography parameters commonly influencing the distribution of Euthynnus affinis are temperature, current, and salinity. The oceanography of Sunda Strait is influenced by water masses coming from the north that mainly originated from the Java Sea and water masses from the south mainly originated from Indian Ocean. The internal oceanography of Sunda Strait is also influenced by upwelling and monsoon as regional climate anomaly (ENSO and Indian Ocean Dipole Mode. This paper describes the influence of Dipole Mode (positive and negative event and ENSO (El- Nino/La-Nina to the catch dynamics of neritic tuna particularly in Sunda Straits waters. The results shown that regional climate anomaly influenced neritic tuna catch and its composition. The catches Euthynnus affinis in phase negative dipole mode or La-Nina were higher and dominated the catch composition of pelagic fishes of Sunda Strait. Similar situation also is showen by Scomberomorus commerson.

  6. An auroral westward flow channel (AWFC and its relationship to field-aligned current, ring current, and plasmapause location determined using multiple spacecraft observations

    Directory of Open Access Journals (Sweden)

    M. L. Parkinson

    2007-02-01

    Full Text Available An auroral westward flow channel (AWFC is a latitudinally narrow channel of unstable F-region plasma with intense westward drift in the dusk-to-midnight sector ionosphere. AWFCs tend to overlap the equatorward edge of the auroral oval, and their life cycle is often synchronised to that of substorms: they commence close to substorm expansion phase onset, intensify during the expansion phase, and then decay during the recovery phase. Here we define for the first time the relationship between an AWFC, large-scale field-aligned current (FAC, the ring current, and plasmapause location. The Tasman International Geospace Environment Radar (TIGER, a Southern Hemisphere HF SuperDARN radar, observed a jet-like AWFC during ~08:35 to 13:28 UT on 7 April 2001. The initiation of the AWFC was preceded by a band of equatorward expanding ionospheric scatter (BEES which conveyed an intense poleward electric field through the inner plasma sheet. Unlike previous AWFCs, this event was not associated with a distinct substorm surge; rather it occurred during an interval of persistent, moderate magnetic activity characterised by AL~−200 nT. The four Cluster spacecraft had perigees within the dusk sector plasmasphere, and their trajectories were magnetically conjugate to the radar observations. The Waves of High frequency and Sounder for Probing Electron density by Relaxation (WHISPER instruments on board Cluster were used to identify the plasmapause location. The Imager for Magnetopause-to-Aurora Global Exploration (IMAGE EUV experiment also provided global-scale observations of the plasmapause. The Cluster fluxgate magnetometers (FGM provided successive measurements specifying the relative location of the ring current and filamentary plasma sheet current. An analysis of Iridium spacecraft magnetometer measurements provided estimates of large-scale ionospheric FAC in relation to the AWFC evolution. Peak flows in the AWFC were located close to the peak of a Region 2

  7. 33 CFR 334.1180 - Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. 334.1180 Section 334.1180 Navigation and Navigable... REGULATIONS § 334.1180 Strait of Juan de Fuca, Wash.; air-to-surface weapon range, restricted area. (a) The...

  8. Multi-model ensemble estimation of volume transport through the straits of the East/Japan Sea

    Science.gov (United States)

    Han, Sooyeon; Hirose, Naoki; Usui, Norihisa; Miyazawa, Yasumasa

    2016-01-01

    The volume transports measured at the Korea/Tsushima, Tsugaru, and Soya/La Perouse Straits remain quantitatively inconsistent. However, data assimilation models at least provide a self-consistent budget despite subtle differences among the models. This study examined the seasonal variation of the volume transport using the multiple linear regression and ridge regression of multi-model ensemble (MME) methods to estimate more accurately transport at these straits by using four different data assimilation models. The MME outperformed all of the single models by reducing uncertainties, especially the multicollinearity problem with the ridge regression. However, the regression constants turned out to be inconsistent with each other if the MME was applied separately for each strait. The MME for a connected system was thus performed to find common constants for these straits. The estimation of this MME was found to be similar to the MME result of sea level difference (SLD). The estimated mean transport (2.43 Sv) was smaller than the measurement data at the Korea/Tsushima Strait, but the calibrated transport of the Tsugaru Strait (1.63 Sv) was larger than the observed data. The MME results of transport and SLD also suggested that the standard deviation (STD) of the Korea/Tsushima Strait is larger than the STD of the observation, whereas the estimated results were almost identical to that observed for the Tsugaru and Soya/La Perouse Straits. The similarity between MME results enhances the reliability of the present MME estimation.

  9. Sea level trend and variability in the Singapore Strait

    Directory of Open Access Journals (Sweden)

    P. Tkalich

    2013-03-01

    Full Text Available Sea level in the Singapore Strait (SS exhibits response to various scale phenomena, from local to global. Longest tide gauge records in SS are analysed to derive local sea level trend and annual, inter-annual and multi-decadal sea level variability, which then are attributed to regional and global phenomena. Annual data gaps are reconstructed using functions correlating sea level variability with ENSO. At annual scale, sea level anomalies in SS are (quasi-periodic monsoon-driven, of the order of ±20 cm, the highest during northeast monsoon and the lowest during southwest monsoon. Interannual regional sea level drops are associated with El Niño events, while the rises are correlated with La Niña episodes; both variations are in the range of ±5 cm. At multi-decadal scale, annual measured sea levels in SS are varying with global mean sea level, rising at the rate 1.2–1.7 mm yr−1 for 1975–2009, 1.8–2.3 mm yr−1 for 1984–2009 and 1.9–4.6 mm yr−1 for 1993–2009. When SS rates are compared with the global trends (2.0, 2.4 and 2.8 mm yr−1, respectively derived from tide gauge measurements for the same periods, they are smaller in the earlier era and considerably larger in the recent one. Taking into account the first estimate of land subsidence rate, 1–1.5 mm yr−1 in Singapore, the recent trend of absolute sea level rise in SS follows regional tendency.

  10. Application of INCSEA principles to the Taiwan Strait.

    Energy Technology Data Exchange (ETDEWEB)

    Wen-Chung, Chai (Taiwan Navy, Taiwan)

    2003-06-01

    The waters surrounding Taiwan are important international waterways. In addition to merchant ships of every nation, the warships of the United States, Japan, Russia, and China may appear in these waters. No hostility is expected between Taiwan and the United States, Japan, or Russia; however, Taiwan and China have a tense relationship, and both sides face a potential for naval incidents. As Taiwan and China expand their naval capability, the International Maritime Organization Convention for the lnternational Regulations for Preventing Collisions at Sea may not be sufficient to prevent naval incidents, any of which might develop into conflict or war. Therefore, China and Taiwan need to develop maritime confidence building measures (CBMs) that could reduce the chance of naval incidents and strengthen mutual trust and confidence. Among the variety of maritime CBM concepts for military purposes, the most successful and effective measure has been the 1972 U.S.-Soviet Union Agreement on the Prevention of Incidents On and Over the High Seas (INCSEA). The success of the agreement demonstrates that CBMs represent a workable alternative to traditional arms controls. The purpose of this paper is to suggest a concrete approach to the constraint of naval activities between China and Taiwan to reduce accidents and misunderstandings. This paper outlines the categories and characteristics of incidents at sea. Next, the author identifies the successful factors of the U.S.-Soviet INCSEA and applies the INCSEA concept to the Taiwan Strait. Finally, the author develops a framework of options and a step-by-step approach for establishing an INCSEA between Taiwan and China.

  11. The freshwater composition of the Fram Strait outflow derived from a decade of tracer measurements

    DEFF Research Database (Denmark)

    Dodd, Paul A.; Rabe, Benjamin; Hansen, Edmond

    2012-01-01

    are also the first to show positive fractions of sea ice meltwater at the surface near the core of the EGC. Sections from September 2009–2011 show an increased input of sea ice meltwater at the surface relative to older September sections. This suggests that more sea ice now melts back into the surface...... meltwater inventories, suggesting that meteoric water and brine may be delivered to Fram Strait together from a common source. We find that the freshwater outflow at Fram Strait exhibits a similar meteoric water to net sea ice meltwater ratio as the central Arctic Ocean and Siberian shelves, suggesting......The composition of the Fram Strait freshwater outflow is investigated by comparing 10 sections of concurrent salinity, δ18O, nitrate and phosphate measurements collected between 1997 and 2011. The largest inventories of net sea ice meltwater are found in 2009, 2010 and 2011. The 2009–2011 sections...

  12. Preliminary crustal model from seismological observations at the Messina Straits network

    Directory of Open Access Journals (Sweden)

    B. FEDERICO

    1979-06-01

    Full Text Available Starting from a general tectonic description of the Strait of Messina,
    what follows is an explanation of the criteria adopted in choosing
    sites for seismic stations of the Straits network.
    The main lithological and mechanical characteristics of the terrains
    where the stations are been located, together with the equipment used,
    are mentioned, are looked at in relation to the positions of the main
    centres of seismic activity both actual and in recent past, and to the
    microseismic energy threshold.
    A number of observations regarding the seismic crisis in the Gulf
    of Patti (1978 are analized, with the aim of suggesting a crustal model
    compatible with the area of the Messina Straits.

  13. Preliminary result of 3-D attenuation tomography beneath Sunda Strait and western part of Java

    Science.gov (United States)

    Anshori, Muhajir; Nugraha, Andri Dian; Puspito, Nanang T.

    2017-07-01

    Sunda strait lies in the transition zone of two different subduction system that is almost perpendicular to the subduction in southern Java and oblique subduction in western Sumatra. The series of major disasters such as earthquakes and volcanic eruptions is a manifestation of its tectonic setting complexity. We used selected waveform data from724 earthquakes that occurred around the Sunda strait and western part of Java from 2009 - 2015 recorded by 21 MCGA network stations to construct three dimensional image of seismic attenuation. Frequency independent attenuation operators (t*) was determined using spectral fitting method for P and S wave arrivals, respectively. The inversion was performed using simul2000 algorithm to image the lateral and vertical variations of Qp and Qs value in the Sunda Strait and western part of Java. Some interesting features such as subducting slab, mantle wedge, magma chamber under volcanos and fault zones can be imaged well.

  14. Polycyclic aromatic hydrocarbons in coastal sediment of klang strait, Malaysia: distribution pattern, risk assessment and sources.

    Directory of Open Access Journals (Sweden)

    Seyedeh Belin Tavakoly Sany

    Full Text Available Concentration, source, and ecological risk of polycyclic aromatic hydrocarbons (PAHs were investigated in 22 stations from surface sediments in the areas of anthropogenic pollution in the Klang Strait (Malaysia. The total PAH level in the Klang Strait sediment was 994.02±918.1 µg/kg dw. The highest concentration was observed in stations near the coastline and mouth of the Klang River. These locations were dominated by high molecular weight PAHs. The results showed both pyrogenic and petrogenic sources are main sources of PAHs. Further analyses indicated that PAHs primarily originated from pyrogenic sources (coal combustion and vehicular emissions, with significant contribution from petroleum inputs. Regarding ecological risk estimation, only station 13 was moderately polluted, the rest of the stations suffered rare or slight adverse biological effects with PAH exposure in surface sediment, suggesting that PAHs are not considered as contaminants of concern in the Klang Strait.

  15. POTENTIAL PRODUCTION OF DEMERSAL FISH STOCK IN THE MALACCA STRAIT OF INDONESIA

    Directory of Open Access Journals (Sweden)

    Purwanto Purwanto

    2015-06-01

    Full Text Available Malacca Strait is one of the main fishing areas for demersal fishery in Indonesia. To support the management of that fishery, an assessment of the demersal fish stock was conducted. This study estimated that the maximum sustainable yield and the optimal catch per unit effortof demersal fishery in the Malacca Strait were about 106.8 thousand tons/year and 28.5 tons per unit of Danish seine, respectively, resulting from the operation of 3,752 Danish seines. Unfortunately, fishing effort was higher than its optimum level and the fish stock was over-exploited since 2003. To recover the demersal fish stock to its optimum level and to ensure the optimal fish production from demersal fishery in the Malacca Strait, it was necessary to reduce fishing effort at about 67% from its level in 2011.

  16. Performance assessment for an operational ocean model of the Taiwan Strait

    Science.gov (United States)

    Lin, Xinyou; Yan, Xiao-Hai; Jiang, Yuwu; Zhang, Zhenchang

    2016-06-01

    The Taiwan Strait Nowcast/Forecast System (TFOR), which is based on the Regional Ocean Modeling System, may be the first operational ocean model to include both tide and circulation processes in the Taiwan Strait. In this study, we assessed the performance of TFOR by investigating the differences between observational data and the results obtained by TFOR, thereby illustrating the ability of TFOR to reproduce significant physical processes. We also evaluated the utility and reliability of TFOR products for successful applications in maritime search and rescue. The mean bias, root mean-squared difference, correlation coefficient (CC), and Willmott skill for the differences in temperature between the cruise observations and the TFOR results were -0.01°C, 1.2°C, 0.87, and 0.92, respectively, and those for the corresponding salinity results were 0.06 PSU, 0.4 PSU, 0.74, and 0.83, respectively. The distributions of the TFOR M2 harmonic constants indicated that TFOR simulates the tidal characteristics well in the Taiwan Strait. The CC between the Taiwan Strait volume transport based on the TFOR results and the along-strait wind stress was 0.77, thereby indicating that monsoon winds exert an important influence on the variability in volume transport through the Taiwan Strait. Statistical analyses of the TFOR results showed that the annual, spring, summer, autumn, and winter mean transport volumes were 1.16, 1.28, 2.52, 0.80, and 0.04 Sv, respectively. In conclusion, the TFOR is robust and it can simulate the temperature, salinity, and velocity in a reasonable and stable manner.

  17. The influence of the Bering Strait on the circulation in a coarse resolution global ocean model

    Science.gov (United States)

    Reason, C. J. C.; Power, S. B.

    1994-05-01

    An ocean general circulation model of global domain, full continental geometry and bottom topography, is used to study the influence of the Bering Strait on the general circulation by comparing equilibrium solutions obtained with and without a land-bridge between Siberia and Alaska. The model is integrated with restoring boundary conditions (BC) on temperature and salinity, and later, with mixed BC in which a restoring BC on temperature is maintained but a specified flux condition on salinity is imposed. In both cases, the effect of the Bering Strait is to allow a flow of about 1.25 1.5 Sv from the North Pacific to the Arctic Ocean and, ultimately, back to the North Pacific along the western boundary current regions of the Atlantic and Indian Oceans. When a restoring BC on salinity is used, the overturning associated with North Atlantic Deep Water and Antarctic Intermediate Water formation are increased if the Bering Strait is present in the model geometry. The result of switching to a specified flux BC on salinity is to cause a transition in the THC in which the overturning associated with North Atlantic Deep Water formation increases from about 12 Sv to about 22 Sv. This transition occurs in an essentially smooth fashion with no significant variability and is about 12% smaller in magnitude if the Bering Strait is present in the model geometry. Because the Bering Strait appears to exert some influence on the general circulation and the formation of deep water masses, it is recommended that this Strait be included in the geometry of similar resolution models designed to study the deep ocean and potential changes in climate.

  18. Flow, waves and water exchange in the Suur Strait, Gulf of Riga, in 2008:

    Directory of Open Access Journals (Sweden)

    Tarmo Kõuts

    2011-03-01

    Full Text Available Wind, flow and wave measurements were performed in November-December in 2008 in the relatively narrowand shallow Suur Strait connecting the waters of the Väinameri and the Gulf of Riga.During the measurement period wind conditions were extremely variable, including a severe storm on 23 November. The flow speedalong the strait varied between ±0.2 m s-1, except for the 0.4 m s-1 that occurred after the storm as a result of the sealevel gradient. The mean and maximum significant wave heights were 0.53 m and 1.6 m respectively. Because of their longer fetch, southerlywinds generated higher waves in the strait than winds from the north. All wave events caused by the stronger southerly windsinduced sediment resuspension, whereas the current-induced shear velocity slightly exceeded the critical value for resuspensiononly when the current speed was 0.4 m s-1. A triple-nested two-dimensional high resolution (100 m in the Suur Strait circulation model and the SWANwave model were used to simulate water exchange in 2008 and the wave-induced shear velocity field in the Suur Strait respectively. Circulation model simulations demonstrated that water exchange was highly variable, that cumulative transport followed an evident seasonal cycle, and that there was an grossannual outflow of 23 km3 from the Gulf of Riga. The horizontal distribution of wave-induced shear velocityduring the strong southerly wind event indicated large shear velocities and substantial horizontal variability. The shearvelocities were less than the critical value for resuspension in the deep area of the Suur Strait.

  19. Dextral strike-slip along the Kapıdağ shear zone (NW Turkey): evidence for Eocene westward translation of the Anatolian plate

    Science.gov (United States)

    Türkoğlu, Ercan; Zulauf, Gernold; Linckens, Jolien; Ustaömer, Timur

    2016-10-01

    The northern part of the Kapıdağ Peninsula (Marmara Sea, NW Turkey) is affected by the E-W trending Kapıdağ shear zone, which cuts through calc-alkaline granitoids of the Ocaklar pluton resulting in mylonitic orthogneiss. Macroscopic and microscopic shear-sense indicators, such as SC fabrics, shear bands, σ-clasts and mica fish, unequivocally suggest dextral strike-slip for the Kapıdağ shear zone. Based on petrographic data, deformation microfabrics of quartz and feldspar, and the slip systems in quartz, the dextral shearing should have been active at T = 500-300 °C and P < 5 kbar. Published K-Ar and 39Ar-40Ar cooling ages of hornblende and biotite suggest that cooling below 500-300 °C occurred during the Eocene (ca. 45-ca. 35 Ma), meaning that the Kapıdağ shear zone should have been active during Middle to Late Eocene times. The differential stress related to the shearing was <50 MPa as is indicated by the size of recrystallized quartz grains. Based on the new and published data, it is concluded that the westward movement of the Anatolian plate might have been active almost continuously from the Middle Eocene until recent times.

  20. Description of gravity cores from San Pablo Bay and Carquinez Strait, San Francisco Bay, California

    Science.gov (United States)

    Woodrow, Donald L.; John L. Chin,; Wong, Florence L.; Fregoso, Theresa; Jaffe, Bruce E.

    2017-06-27

    Seventy-two gravity cores were collected by the U.S. Geological Survey in 1990, 1991, and 2000 from San Pablo Bay and Carquinez Strait, California. The gravity cores collected within San Pablo Bay contain bioturbated laminated silts and sandy clays, whole and broken bivalve shells (mostly mussels), fossil tube structures, and fine-grained plant or wood fragments. Gravity cores from the channel wall of Carquinez Strait east of San Pablo Bay consist of sand and clay layers, whole and broken bivalve shells (less than in San Pablo Bay), trace fossil tubes, and minute fragments of plant material.

  1. Satellite estimate of freshwater exchange between the Indonesian Seas and the Indian Ocean via the Sunda Strait

    Science.gov (United States)

    Potemra, James T.; Hacker, Peter W.; Melnichenko, Oleg; Maximenko, Nikolai

    2016-07-01

    The straits in Indonesia allow for low-latitude exchange of water between the Pacific and Indian Oceans. Collectively known as the Indonesian Throughflow (ITF), this exchange is thought to occur primarily via the Makassar Strait and downstream via Lombok Strait, Ombai Strait, and Timor Passage. The Sunda Strait, between the islands of Sumatra and Java, is a very narrow (≈10 km) and shallow (≈20 m) gap, but it connects the Java Sea directly to the Indian Ocean. Flow through this strait is presumed to be small, given the size of the passage; however, recent observations from the Aquarius satellite indicate periods of significant freshwater transport, suggesting the Sunda Strait may play a more important role in Pacific to Indian Ocean exchange. The nature of this exchange is short-duration (several days) bursts of freshwater injected into the eastern Indian Ocean superimposed on a mean seasonal cycle. The mean volume transport is small averaging about 0.1 Sv toward the Indian Ocean, but the freshwater transport is nonnegligible (estimated at 5.8 mSv). Transport through the strait is hydraulically controlled and directly correlates to the along-strait pressure difference. The episodic low-salinity plumes observed by Aquarius do not, however, appear to be forced by this same mechanism but are instead controlled by convergence of flow at the exit of the Strait in the Indian Ocean. Numerical model results show the fate of this freshwater plume varies with season and is either advected to the northwest along the coast of Sumatra or southerly into the ITF pathway.

  2. Abrupt Atmospheric Methane Increases Associated With Hudson Strait Heinrich Events

    Science.gov (United States)

    Rhodes, R.; Brook, E.; Chiang, J. C. H.; Blunier, T.; Maselli, O. J.; McConnell, J. R.; Romanini, D.; Severinghaus, J. P.

    2015-12-01

    The drivers of abrupt climate change during the Last Glacial Period are not well understood. While Dansgaard-Oeschger (DO) cycles are thought to be linked to variations in the strength of the Atlantic Meridional Ocean Circulation (AMOC), it is not clear how or if Heinrich Events—extensive influxes of icebergs into the North Atlantic Ocean that impacted global climate and biogeochemistry—are related. An enduring problem is the difficultly in dating iceberg rafted debris deposits that typically lack foraminifera. Here we present an ultra-high resolution record of methane from the West Antarctic Ice Sheet Divide ice core at unprecedented, continuous temporal resolution from 67.2-9.8 ka BP, which we propose constrains the timing of Heinrich events. Our methane record essentially mirrors Greenland ice core stable isotope variability across D-O events, except during Heinrich stadials 1, 2, 4 and 5. Partway through these stadials only, methane increases abruptly and rapidly, as at the onset of a D-O event but Greenland temperature exhibits no equivalent response. Speleothem records exhibit signatures of drought in the Northern extra-tropics and intensified monsoonal activity over South America at these times. We use a simple heuristic model to propose that cold air temperatures and extensive sea ice in the North, resulting from Heinrich events, caused extreme reorganization of tropical hydroclimate. This involved curtailment of the seasonal northerly migration of tropical rain belts, leading to intensification of rainfall over Southern Hemisphere tropical wetlands, thus allowing production of excess methane relative to a 'normal' Greenland stadial. We note that this mechanism can operate if AMOC is already in a slowed state when a Heinrich event occurs, as paleo-evidence suggests it was. Heinrich events and associated sea ice cover would therefore act to prolong the duration of this AMOC state. Our findings place the big four Heinrich events of Hudson Strait origin

  3. Single-ping ADCP measurements in the Strait of Gibraltar

    Science.gov (United States)

    Sammartino, Simone; García Lafuente, Jesús; Naranjo, Cristina; Sánchez Garrido, José Carlos; Sánchez Leal, Ricardo

    2016-04-01

    In most Acoustic Doppler Current Profiler (ADCP) user manuals, it is widely recommended to apply ensemble averaging of the single-pings measurements, in order to obtain reliable observations of the current speed. The random error related to the single-ping measurement is typically too high to be used directly, while the averaging operation reduces the ensemble error of a factor of approximately √N, with N the number of averaged pings. A 75 kHz ADCP moored in the western exit of the Strait of Gibraltar, included in the long-term monitoring of the Mediterranean outflow, has recently served as test setup for a different approach to current measurements. The ensemble averaging has been disabled, while maintaining the internal coordinate conversion made by the instrument, and a series of single-ping measurements has been collected every 36 seconds during a period of approximately 5 months. The huge amount of data has been fluently handled by the instrument, and no abnormal battery consumption has been recorded. On the other hand a long and unique series of very high frequency current measurements has been collected. Results of this novel approach have been exploited in a dual way: from a statistical point of view, the availability of single-ping measurements allows a real estimate of the (a posteriori) ensemble average error of both current and ancillary variables. While the theoretical random error for horizontal velocity is estimated a priori as ˜2 cm s-1 for a 50 pings ensemble, the value obtained by the a posteriori averaging is ˜15 cm s-1, with an asymptotical behavior starting from an averaging size of 10 pings per ensemble. This result suggests the presence of external sources of random error (e.g.: turbulence), of higher magnitude than the internal sources (ADCP intrinsic precision), which cannot be reduced by the ensemble averaging. On the other hand, although the instrumental configuration is clearly not suitable for a precise estimation of turbulent

  4. A westward propagating slab tear model for Late Triassic Qinling Orogenic Belt geodynamic evolution: Insights from the petrogenesis of the Caoping and Shahewan intrusions, central China

    Science.gov (United States)

    Hu, Fangyang; Liu, Shuwen; Zhang, Wanyi; Deng, Zhengbin; Chen, Xu

    2016-10-01

    temperature (TZr = 770-817 °C, comparing with Caoping intrusion of TZr = 727-773 °C), together with the magma mixing and isothermal decompression processes. Integrated with previous regional data, the SQB shows that mantle-derived magmatic activations initiated at ~ 234 Ma near Wudang in the east, and westward systematically decreased to ~ 222-219 Ma near Caoping and to 212-208 Ma near Yangba. We attribute this temporal-spatial distribution of mantle-derived magmatism within the SQB to the progressive tear of the subducted oceanic slab. Combined with sedimentary studies on the foreland basins, paleomagnetic studies as well as numerical and seismic tomography models of slab break-off, we propose that the ~ 225-205 Ma magmatism in the SQB resulted from a westward slab tear following the collision between the NCC and YZC.

  5. Greater circadian disadvantage during evening games for the National Basketball Association (NBA), National Hockey League (NHL) and National Football League (NFL) teams travelling westward.

    Science.gov (United States)

    Roy, Jonathan; Forest, Geneviève

    2017-06-01

    We investigated the effects of a circadian disadvantage (i.e. playing in a different time zone) on the winning percentages in three major sport leagues in North America: the National Basketball Association, the National Hockey League and the National Football League. We reviewed 5 years of regular season games in the National Basketball Association, National Hockey League and National Football League, and noted the winning percentage of the visiting team depending on the direction of travel (west, east, and same time zone) and game time (day and evening games). T-tests and analysis of variance were performed to evaluate the effects of the circadian disadvantage, its direction, the number of time zones travelled, and the game time on winning percentages in each major league. The results showed an association between the winning percentages and the number of time zones traveled for the away evening games, with a clear disadvantage for the teams travelling westward. There was a significant difference in the teams' winning percentages depending on the travelling direction in the National Basketball Association (F2,5908  = 16.12, P < 0.0001) and the National Hockey League (F2,5639  = 4.48, P = 0.011), and a trend was found in the National Football League (F2,1279  = 2.86, P = 0.058). The effect of the circadian disadvantage transcends the type of sport and needs to be addressed for greater equity among the western and eastern teams in professional sports. These results also highlight the importance of circadian rhythms in sport performance and athletic competitions. © 2017 European Sleep Research Society.

  6. Magnetospheric solitary structure maintained by 3000 km/s ions as a cause of westward moving auroral bulge at 19 MLT

    Directory of Open Access Journals (Sweden)

    M. Yamauchi

    2009-07-01

    Full Text Available In the evening equatorial magnetosphere at about 4 RE geocentric distance and 19 MLT, the four Cluster spacecraft observed a solitary structure with a width of about 1000~2000 km in the propagation direction. The solitary structure propagates sunward with about 5~10 km/s carrying sunward electric field (in the propagation direction of up to about 10 mV/m (total potential drop of about 5~10 kV, depletion of magnetic field of about 25%, and a duskward E×B convection up to 50 km/s of He+ rich cold plasma without O+. At the same time, auroral images from the IMAGE satellite together with ground based geomagnetic field data showed a westward (sunward at this location propagating auroral bulge at the magnetically conjugate ionosphere with the solitary structure. The solitary structure is maintained by flux enhancement of selectively 3000 km/s ions (about 50 keV for H+, 200 keV for He+, and 750 keV for O+. These ions are the main carrier of the diamagnetic current causing the magnetic depletion, whereas the polarization is maintained by different behavior of energetic ions and electrons. Corresponding to aurora, field-aligned accelerated ionospheric plasma of several keV appeared at Cluster from both hemispheres simultaneously. Together with good correspondence in location and propagation velocity between the auroral bulge and the solitary structure, this indicates that the sunward moving auroral bulge is caused by the sunward propagation of the solitary structure which is maintained by energetic ions. The solitary structure might also be the cause of Pi2-like magnetic variation that started simultaneously at Cluster location.

  7. Carbon flows in the benthic food web at the deep-sea observatory HAUSGARTEN (Fram Strait)

    NARCIS (Netherlands)

    Van Oevelen, D.; Bergmann, M.; Soetaert, K.E.R.; Bauerfeind, E.; Hasemann, C.; Klages, M.; Schewe, I.; Soltwedel, T.; Budaeva, N.E.

    2011-01-01

    The HAUSGARTEN observatory is located in the eastern Fram Strait (Arctic Ocean) and used as long-term monitoring site to follow changes in the Arctic benthic ecosystem. Linear inverse modelling was applied to decipher carbon flows among the compartments of the benthic food web at the central

  8. Water mass of the northward throughflow in the Bering Strait in the summer of 2003

    Institute of Scientific and Technical Information of China (English)

    ZHAO Jinping; SHI Jiuxin; GAO Guoping; JIAO Yutian; ZHANG Hongxin

    2006-01-01

    The temperature and salinity data obtained by the Chinese national arctic research expedition (CHINARE2003) are used to study the water structure in the Bering Strait and ambient regions. Four water masses appeared in the research region: the intermediate Bering Sea water mass (IBWM), the Alaska coastal water (ACW), the Anadyr water (AW) and the Bering shelf water (BSW). The AW originates from the IBWM, but the upper layer water has been greatly altered. In the cruise on 28/29 July 2003, there were only the BSW and ACW in a section across the Bering Strait (BS section), but in the September 12/13 cruise, the AW, BSW and ACW flowed parallelly into the Bering Strait. The upper waters of these water masses were all altered due to ice melting, runoff, solar radiation, and wind mixing. The waters in the central and northern parts of Bering Strait stratified by two uniform layers,were expressed as the typical feature of the water masses originating from the pacific. A two-layer structure also dominated the vertical stratification in most part of the Chukchi Sea. An obvious subseasonal variation was observed in the BS section, which caused varying transportation of fresh water,heat, and substance, and produced a long-term and extensive impact on the Arctic Ocean.

  9. 33 CFR 100.1307 - Special Local Regulations, Strait Thunder Performance, Port Angeles, WA.

    Science.gov (United States)

    2010-07-01

    ... Thunder Performance, Port Angeles, WA. 100.1307 Section 100.1307 Navigation and Navigable Waters COAST... § 100.1307 Special Local Regulations, Strait Thunder Performance, Port Angeles, WA. (a) Regulated Areas... located near Port Angeles, Washington: Point 1: 48°07′24″ N, 123°25′32″ W; Point 2: 48°07′26″ N,...

  10. Too Distant Shores: The Strait of Gibraltar and the Space of Exception

    Science.gov (United States)

    Gluhovic, Milija

    2008-01-01

    Focusing on "The Sheep and the Whale" ("Le mouton et la baleine," 2001) by Moroccan-Canadian playwright Ahmed Ghazali, this essay examines political and ethical issues concerning human migration from Africa to Europe. The play's representation of human rights abuses in the Strait of Gibraltar and the dilemmas facing illegal…

  11. Plumularian hydroids (Cnidaria: Hydrozoa) from the Strait of Gibraltar and nearby areas

    NARCIS (Netherlands)

    Medel, M.D.; Vervoort, W.

    1995-01-01

    Twenty-four species of plumularian hydroids (Cnidaria: Hydrozoa) from the Strait of Gibraltar area are described and figured, including material from the coasts of southern Spain (between El Portil near the Spanish-Portuguese border and Adra, Mediterranean coast of Granada, c. 3°W) and from Ceuta in

  12. A particle-tracking model for simulating pollutant dispersion in the Strait of Gibraltar.

    Science.gov (United States)

    Periáñez, R

    2004-10-01

    A particle-tracking model to simulate the dispersion of contaminants in the Strait of Gibraltar has been developed. The model solves the hydrodynamic equations off-line and tidal analysis is carried out to determine tidal constants for the two main constituents. Tidal constants and residuals are stored in files that are read by the dispersion model. A lagrangian approach is used to solve dispersion; diffusion and decay are simulated by a Monte Carlo method. A method for assessing the areas of the Strait with higher probability of being affected by contamination occurring after an accident in the shipping routes is given. Generally speaking, the fate of a pollutant discharge strongly depends on wind conditions. Winds from the east tend to retain contamination into the Strait. As a consequence, transverse mixing occurs and both Spain and Morocco coasts are affected by contamination. Under calm conditions and west winds, contaminants are flushed out of the Strait faster and transverse mixing does not occur. Thus, only part of Morocco coast has a higher probability of being affected by contamination.

  13. The family Haleciidae (Cnidaria: Hydrozoa) from the Strait of Gibraltar and nearby areas

    NARCIS (Netherlands)

    Medel, M.D.; García, F.G.; Vervoort, W.

    1998-01-01

    A faunistic study of the family Haleciidae from the Strait of Gibraltar and nearby areas has been made; seven species are described, figured and discussed. Information about the zoogeographical distribution, and conditions of substrates are contributed. A key to distinguish the species of this famil

  14. 76 FR 21330 - Lynn Canal/Icy Straits Resource Advisory Committee

    Science.gov (United States)

    2011-04-15

    ...The Lynn Canal/Icy Straits Resource Advisory Committee will meet in Juneau, Alaska, April 25, 2011. The purpose of this meeting is to orient the new appointees as to the Secure Rural Schools and Community Self-Determination Act of 2008, provide operational guidelines, discuss and adopt specific bylaws for the RAC, and elect a RAC...

  15. Indigenous Language Learning and Maintenance among Young Australian Aboriginal and Torres Strait Islander Children

    Science.gov (United States)

    Verdon, Sarah; McLeod, Sharynne

    2015-01-01

    Internationally, cultural renewal and language revitalisation are occurring among Indigenous people whose lands were colonised by foreign nations. In Australia, the Aboriginal and Torres Strait Islander people are striving for the re-voicing of their mother tongue and the re-practicing of their mother culture to achieve cultural renewal in the…

  16. Plumularian hydroids (Cnidaria: Hydrozoa) from the Strait of Gibraltar and nearby areas

    NARCIS (Netherlands)

    Medel, M.D.; Vervoort, W.

    1995-01-01

    Twenty-four species of plumularian hydroids (Cnidaria: Hydrozoa) from the Strait of Gibraltar area are described and figured, including material from the coasts of southern Spain (between El Portil near the Spanish-Portuguese border and Adra, Mediterranean coast of Granada, c. 3°W) and from Ceuta in

  17. The family Haleciidae (Cnidaria: Hydrozoa) from the Strait of Gibraltar and nearby areas

    NARCIS (Netherlands)

    Medel, M.D.; García, F.G.; Vervoort, W.

    1998-01-01

    A faunistic study of the family Haleciidae from the Strait of Gibraltar and nearby areas has been made; seven species are described, figured and discussed. Information about the zoogeographical distribution, and conditions of substrates are contributed. A key to distinguish the species of this famil

  18. Carbon flows in the benthic food web at the deep-sea observatory HAUSGARTEN (Fram Strait)

    NARCIS (Netherlands)

    Van Oevelen, D.; Bergmann, M.; Soetaert, K.E.R.; Bauerfeind, E.; Hasemann, C.; Klages, M.; Schewe, I.; Soltwedel, T.; Budaeva, N.E.

    2011-01-01

    The HAUSGARTEN observatory is located in the eastern Fram Strait (Arctic Ocean) and used as long-term monitoring site to follow changes in the Arctic benthic ecosystem. Linear inverse modelling was applied to decipher carbon flows among the compartments of the benthic food web at the central HAUSGAR

  19. Report on the Hydroida collected by the "BALGIM" expedition in and around the Strait of Gibraltar

    NARCIS (Netherlands)

    Ramil, F.; Vervoort, W.

    1992-01-01

    A total of 102 species and varieties of hydroids and three unidentifiable species are described or mentioned in the present report, which deals principally with hydroids collected in the IberoMoroccan Bay (and adjacent Atlantic), the Strait of Gibraltar, and the Alboran Sea; for revisionary purposes

  20. Hydraulic theory of sea straits applied to the onset of the Messinian Salinity Crisis

    NARCIS (Netherlands)

    Meijer, P.Th.

    2012-01-01

    Theory for the dynamics of flow in sea straits holds promise to provide, in addition to geological evidence, insight into the configuration of the connection between the Mediterranean Sea and the Atlantic Ocean at the onset of the Messinian Salinity Crisis. This paper, for the first time, systematic

  1. Indigenous Language Learning and Maintenance among Young Australian Aboriginal and Torres Strait Islander Children

    Science.gov (United States)

    Verdon, Sarah; McLeod, Sharynne

    2015-01-01

    Internationally, cultural renewal and language revitalisation are occurring among Indigenous people whose lands were colonised by foreign nations. In Australia, the Aboriginal and Torres Strait Islander people are striving for the re-voicing of their mother tongue and the re-practicing of their mother culture to achieve cultural renewal in the…

  2. The Competition of Tidal Mixing and Freshwater Forcing in Shaping the Outflow from Hudson Strait

    Science.gov (United States)

    2011-04-01

    Strait outflow. Journal of Marine Systems , special issue on Hudson Bay, in press. St. Laurent, P., F. Straneo, J.F. Dumais, D.G. Barber, 2011 What...is the fate of the river waters of Hudson Bay? Journal of Marine Systems , special issue on Hudson Bay, in press. Straneo, F., D. Sutherland, D

  3. Managing Stability in the Taiwan Strait: Non-Military Policy towards Taiwan under Hu Jintao

    Directory of Open Access Journals (Sweden)

    Wu-ueh Chang

    2009-10-01

    Full Text Available China’s Taiwan policy has been one of coupling intimidation (the “stick” approach with coercion (the “carrot” approach, a policy mix which, in the near term, is not likely to change, as is evidenced by the passage of the “Anti-Secession Law” in March, 2005. However, under Hu Jintao, the focus has been on pragmatism. The warm atmosphere that presently reigns in the Taiwan Strait area is unprecedented. Further talks are expected before the two cross-Strait leaders are slated to step down, simultaneously, in 2012. An era of reconciliation and negotiations has dawned. For the first time there is consensus regarding norms of interaction between the two sides. Cross-Strait relations have stabilized after years of tumult. More open, stable and predictable cross-Strait relations are in the interests of both sides. Difficulties surely lie ahead, but they will be dealt with in a different manner than what has been witnessed in the past.

  4. The Hormuz Strait Dam Macroproject— 21st Century Electricity Development Infrastructure Node (EDIN)?

    NARCIS (Netherlands)

    Schuiling, R.D.; Badescu, V.; Cathcart, R.B.; Overveld, P.A.L.C.

    2005-01-01

    Ocean gulfs offer a means of artificially creating a depression, which can be used for a regionally significant hydroelectric macroproject. We examine here the case for a dam at the Strait of Hormuz that blocks a large gulf situated in an arid region. A 35 m evaporation of this concentration basin

  5. Report on the Hydroida collected by the "BALGIM" expedition in and around the Strait of Gibraltar

    NARCIS (Netherlands)

    Ramil, F.; Vervoort, W.

    1992-01-01

    A total of 102 species and varieties of hydroids and three unidentifiable species are described or mentioned in the present report, which deals principally with hydroids collected in the IberoMoroccan Bay (and adjacent Atlantic), the Strait of Gibraltar, and the Alboran Sea; for revisionary purposes

  6. Too Distant Shores: The Strait of Gibraltar and the Space of Exception

    Science.gov (United States)

    Gluhovic, Milija

    2008-01-01

    Focusing on "The Sheep and the Whale" ("Le mouton et la baleine," 2001) by Moroccan-Canadian playwright Ahmed Ghazali, this essay examines political and ethical issues concerning human migration from Africa to Europe. The play's representation of human rights abuses in the Strait of Gibraltar and the dilemmas facing illegal migrants, refugees and…

  7. Last Glacial - Holocene stratigraphic development at the Marmara Sea exit of the Bosphorus Strait, Turkey

    Science.gov (United States)

    Köprülü, Kerem; Alpar, Bedri; Vardar, Denizhan

    2016-03-01

    High resolution Chirp and Sparker data allowed definition and mapping of distinct seismic units in the shallow sediment record (~100 ms) acquired from the southern exit of the Bosphorus Strait; a dynamic depositional environment. The bottommost unit observed in the Chirp data (unit-3) is made up of marine-lacustrine sediments thinning seaward and onlaps the basement rocks which are represented by folded strata in the Sparker data, possibly lower to middle Pleistocene age. It is overlain by a series of prograding deposits along the shelf (unit-2) referring to sediment input from the northern sector depending on the water levels of the paleo Marmara lake's during MIS 3. The uppermost deposits (unit-1) close to the Bosphorus Strait were represented by three separate subunits, unlike to relatively thin drape of sediments observed at the other places in the surrounding regions. The detailed definition of these subunits deduced from the closely-spaced reflection profiles and available radiocarbon ages helped to explain the history of the latest stratigraphic development depending on the connections between the Black Sea and the Sea of Marmara. In addition to the previously proposed major conduits, which controlled the sedimentary deposition at the southern exit of the Bosphorus, namely the Bosphorus Strait and Kurbağalıdere River, another submarine sedimentary pathway at the eastern bank of the strait's channel seems to have delivered sediments directly into the basin.

  8. Too Distant Shores: The Strait of Gibraltar and the Space of Exception

    Science.gov (United States)

    Gluhovic, Milija

    2008-01-01

    Focusing on "The Sheep and the Whale" ("Le mouton et la baleine," 2001) by Moroccan-Canadian playwright Ahmed Ghazali, this essay examines political and ethical issues concerning human migration from Africa to Europe. The play's representation of human rights abuses in the Strait of Gibraltar and the dilemmas facing illegal…

  9. Genetic relationship of Sardinella lemuru from lombok strait with fish rich in omega-3 fatty acid.

    Science.gov (United States)

    Mahrus; Sumitro, Sutiman Bambang; Utomo, Didik Huswo; Sartimbul, Aida; Toha, Abdul Hamid; Widodo, Nashi

    2012-01-01

    Lombok Strait has abundance of Sardine, Sardinella lemuru, which contains such high amount of omega-3 fatty acid (omega-3). However, the genetic relationship of S. lemuru with other commercial fish rich in omega-3 has not been widely studied yet. Studies on genetic proximity of S. lemuru with the other marine fish using 12S rRNA gene is very important in order to obtain genetic information of the Sardine to develop an appropriate strategy for future conservation of the fish in Lombok Strait. The aim of this study was to find out the genetic relationship of Sardinella lemuru living in Lombok Strait with the economically valuable fish and its correlation with omega-3 production. Sardinella lemuru were collected from Lombok Strait, the phylogenetic tree was done based on 12S rRNA gene through a neighbor-joining method to identify the relationship of Sardines and fish rich in omega-3 fatty acid. The phylogenetic tree showed that Sardinella lemuru is similar to Sardinella aurita and has a close similarity with Sardinella maderensis. However, the relationship did not correspond to omega-3 production. Based on the results of the study, it is suggested that the production of omega-3 is not specifically based on the proximity of the species, but it is more associated with conserved domain of Δ6-desaturase. Nevertheless, detailed mechanisms still need to be elucidated.

  10. Invasive pneumococcal disease in New South Wales, Australia: reporting Aboriginal and Torres Strait Islander status improves epidemiology

    Directory of Open Access Journals (Sweden)

    David N Durrheim

    2011-07-01

    Full Text Available The aim of this work was to determine the feasibility of improving Aboriginal and Torres Strait Islander status recording for notifiable diseases using all Invasive Pneumococcal Disease (IPD notifications in a regional area of New South Wales, Australia.In Australia people with IPD are nearly always admitted to hospital and their Aboriginal and Torres Strait Islander status is recorded. Aboriginal and Torres Strait Islander status was determined for IPD notifications by referring to the routine hospital admission data, in a regional area of New South Wales, Australia.There were 234 notifications in the regional area of Hunter New England during the period 2007–2009. Initially, 168 (72% notifications had Aboriginal and Torres Strait Islander status recorded. After referring to the routine hospital admission data the recorded status increased to 232 (99%. Updating the surveillance data required less than five minutes per notification.Referring to routine hospital admission data proved a useful and time-efficient surveillance strategy to increase the proportion of notifications with Aboriginal and Torres Strait Islander status. These data can then be used to better understand the current epidemiology of IPD. Aboriginal and Torres Strait Islander children aged 0–4 years have a two- to threefold higher rate of invasive pneumococcal disease than non-Aboriginal children, thus high levels of timely pneumococcal immunization coverage remain important for young Aboriginal and Torres Strait Islander children.

  11. Piracy in the Horn of Africa: A Comparative Study with Southeast Asia

    Science.gov (United States)

    2009-12-01

    the link between the Indian Ocean and the South China Sea, and other important waterways, such as the Singapore, Lombok and the Sunda Straits. The...The Strait of Malacca in Southeast Asia and lesser known straits, such as the Sumba, Lombok , Luzon, Singapore and Makassar Straits, have long been

  12. Seasonal variability of phytoplankton fluorescence in relation to the Straits of Messina (Sicily tidal upwelling

    Directory of Open Access Journals (Sweden)

    F. Azzaro

    2007-05-01

    Full Text Available In the Straits of Messina the large gradients of tidal displacements as well as the topographic constrictions determine the upwelling of deeper waters in the surface layer. This work describes the seasonal variability of surface distribution of phytoplankton biomass depending on upwelling phenomena. Temperature, salinity, nitrates and phytoplankton fluorescence were measured in 1994 and 1995 by continuous underway surface real-time measurements on board dedicated research boats. Each survey was performed following the dynamic phases of flooding and ebbing tides. Tidal currents are essentially southward during the high tide and northward during the low tide.

    During the low water slack, large spatial gradients of physical-chemical and biological parameters were mainly found, while in the high water slack a diffused phytoplankton fluorescence was observed only in autumn, in coincidence of a seasonal thermocline. Salinity, nitrate and chlorophyll-a fluorescence data revealed a significant positive intercorrelation, whereas they are inversely correlated with temperature. Generally, during winter, the upwelling distribution was limited to narrow zones, while in summer it involved the middle of the Straits and southern zones. During spring in the southern zone of the Straits, maximum of chlorophyll-a fluorescence was detected (May 1995, 0.32 µg-Chla l-1; in summer, when back and forth tidal movements become intense between the Tyrrhenian and the Ionian seas, values was everywhere lower.

    The data set from continuous and repeatable acquisition has allowed the study of different time-space scales in the Straits of Messina, a very strong dynamic environment.

    The Straits system can be compared to an "intermittent pump" which, during the different seasons, before enriched itself and then it provides nutrients to the surrounding basins.

  13. Anthropogenic and natural CO2 exchange through the Strait of Gibraltar

    Directory of Open Access Journals (Sweden)

    J. Ruíz

    2009-01-01

    Full Text Available The exchange of both anthropogenic and natural inorganic carbon between the Atlantic Ocean and the Mediterranean Sea through Strait of Gibraltar was studied for a period of two years under the frame of the CARBOOCEAN project. A comprehensive sampling program was conducted, which was design to collect samples at eight fixed stations located in the Strait in successive cruises periodically distributed through the year in order to ensure a good spatial and temporal coverage. As a result of this monitoring, a time series namely GIFT (GIbraltar Fixed Time series has been established, allowing the generation of an extensive data set of the carbon system parameters in the area. Data acquired during the development of nine campaigns were analyzed in this work. Total inorganic carbon concentration (CT was calculated from alkalinity-pHT pairs and appropriate thermodynamic relationships, with the concentration of anthropogenic carbon (CANT being also computed. Applying a two-layer model of water mass exchange through the Strait and using the transport of the outflowing Mediterranean water recorded in situ during the considered period, a net export of inorganic carbon from the Mediterranean Sea to the Atlantic was obtained, which amounted to 0.025 Pg C yr−1. In contrast, the Atlantic water was found to contain a higher concentration of anthropogenic carbon than the Mediterranean water, resulting in a net flux of CANT towards the Mediterranean basin of 4.2 Tg C yr−1. A carbon balance through the Strait was assessed and fluxes are discussed in relation to the highly diverse estimates available in the literature for the area. This work unequivocally confirms the relevant role of the Strait of Gibraltar as a controlling point for the biogeochemical exchanges occurring between the Mediterranean Sea and the Atlantic Ocean and emphasizes the influence of the Mediterranean basin in the carbon inventories of the North Atlantic.

  14. Geological Features Inferred from Local Seismic Tomography in the Sunda Strait and West Java regions, Indonesia

    Science.gov (United States)

    Nugraha, A. D.; Sakti, A. P.; Rohadi, S.; Widiyantoro, S.

    2012-12-01

    We have conducted seismic tomographic inversions to obtain a P-wave seismic velocity structure beneath the Sunda Strait and West Java regions, Indonesia. The Sunda Strait is located in a complex geological system i.e. in the transition from the oblique subduction beneath Sumatra to the nearly perpendicular subduction below Java. The Krakatau active volcano is located in the Sunda Strait. In this study, we have used selected P-wave arrival times from the data catalogs of the SeisComP-BMKG network (from 2009 to 2011) and the BMKG BALAI II network (from 1992 to 2011) compiled by Badan Meteorologi,Klimatologi dan Geofisika (BMKG), Indonesia. In total, there are 1,598 local earthquakes and 10,366 P-wave phases from 25 seismographic stations that have been used for the tomographic inversions. We have also relocated the hypocenter locations along with velocity inversions simultaneously. Our preliminary results depict some prominent geological features that include: (1) a low velocity anomaly beneath north of the Ujung Kulon region, which coincides with a low gravity anomaly resulting from a previous study, (2) a low velocity anomaly alignment beneath the Krakatau volcano in the Sunda Strait, (3) a sharp contrast in velocity anomalies extending from Pelabuhan Ratu towards Jakarta with a strike of SW-NE, and (4) a low velocity anomaly in the offshore of Pelabuhan Ratu that may be correlated with the continuation of the Cimandiri fault zone. More detailed information will be presented during the meeting. Keywords: tomography, Sunda Strait, West Java, velocity anomaly

  15. Multidecadal freshening and lightening in the deep waters of the Bransfield Strait, Antarctica

    Science.gov (United States)

    Dotto, Tiago S.; Kerr, Rodrigo; Mata, Mauricio M.; Garcia, Carlos A. E.

    2016-06-01

    The deep waters of the Bransfield Strait receive considerable amounts of water from the Weddell Sea continental shelf. The restricted connections to the surrounding ocean and relatively easier access makes the Bransfield Strait an important proxy region for monitoring changes in the dense Weddell Sea shelf water masses, which are an important precursor of Antarctic Bottom Water (AABW). Long-term hydrographic data from the period 1960s-2010s showed freshening and lightening of the deep water masses of the Bransfield Strait, which was likely caused by large freshwater inputs originating from the western shelf of the Weddell Sea. The rates of freshening and lightening were -0.0010 ± 0.0005 yr-1 and -0.0016 ± 0.0014 kg m-3 yr-1 for the central basin, respectively, and -0.0010 ± 0.0006 yr-1 and -0.0029 ± 0.0013 kg m-3 yr-1 for the eastern basin, respectively. The deep waters showed a high degree of interannual thermohaline variability, which appeared to be caused by changes in the proportions of source water mass mixing between the years. Statistically significant negative correlations between salinity/neutral density fields and the Southern Annular Mode (SAM) were observed (-0.56 and -0.62 for the central basin, respectively, and -0.58 and -0.68 for the eastern basin, respectively) between 1980 and 2014. During SAM positive phases, communication between the Weddell Sea and the Bransfield Strait is reduced, which leads to less saline and lighter water masses in the Bransfield Strait; however, the opposite trends are observed during SAM negative phases.

  16. Geodiversity of a large meander bend in the Little Belt strait in the inner Danish waters

    Science.gov (United States)

    Brandbyge Ernstsen, Verner; Øbro Hansen, Lars; Becker, Marius; Brivio, Lara; Vang, Torben; Lynnerup Trinhammer, Per; Andresen, Katrine Juul; Seidenkrantz, Marit-Solveig; Boldreel, Lars Ole; Bartholdy, Jesper

    2017-04-01

    The Little Belt strait in the inner Danish waters is characterised by a high biodiversity, and continuous monitoring of flora and fauna and the water quality is undertaken by the authorities. However, the surface sedimentology and geomorphology, i.e. elements of the geodiversity, are less well-constrained. The aim of this study is to investigate the surface sediment and morphology of a large meander bend (with a channel width of 1 km) located between the two bridges crossing the strait (a channel reach of 4 km) in order to assess a potential coupling between geodiversity and biodiversity. More specifically, the objectives are 1) to identify and classify morphological units for creating a geomorphological map, 2) to quantify surface material characteristics for creating a surface material map, and 3) to develop a conceptual model of the substrate and the morphology and morphodynamics in the meander bend between the two bridges in the strait. Preliminary results reveal a diverse morphology in the meander bend; and the annual morphological changes reveal complex sediment transport patterns along and across the bend. Likewise significant sediment sorting trends exist along and across the meander bend. Hence, the preliminary results indicate a high geodiversity in the strait. Acknowledgements The data were collected as part of the MSc course Marine Geoscience, a joint MSc course between the Department of Geosciences and Natural Resource Management at the University of Copenhagen and the Department of Geoscience at Aarhus University. Additional data were included from the research project Control in the Danish Straits 1 (CiDS-1) funded by the Danish Centre for Marine Research (PI Morten Holtegaard). Thanks to the crew on board RV Aurora.

  17. Introduced marine species: Management arrangements of consideration for the Torres Strait

    Science.gov (United States)

    Neil, Kerry M.; Hilliard, Robert; Russell, Barry; Clark, Paul

    2008-09-01

    Introduced marine species (IMS) can have significant impacts on economic, ecological, social and cultural aspects of coastal marine environments. There is, therefore, a need to minimise these impacts through the implementation of comprehensive and consistent management strategies and monitoring processes that work towards preventing introductions, detecting introductions if they were to occur and managing incursions should they be detected. There is also the need to ensure that approaches taken are comparable to provide consistency of IMS management effort, particularly across areas that are multi-jurisdictional (e.g. spanning State or Territory borders). A number of studies have examined IMS, their vectors and management arrangements for the Torres Strait region, a multi-jurisdictional area between Queensland, Australia and Papua New Guinea. This paper presents information from a baseline survey conducted in the Torres Strait for marine pests in conjunction with a synthesis of information from other studies on IMS risks, their vectors and management strategies of relevance to the Torres Strait region. A number of strengths, but also gaps, between the various jurisdictions have been identified and discussed. Processes such as the establishment of Biosecurity Queensland as a specialist group and the development of the National System for the Prevention and Management of Marine Pest Incursions are occurring. However, the Torres Strait region is at current risk of marine pest inoculation, particularly for species such as Perna viridis, and management strategies to minimise this risk are lacking. The information presented here will assist management groups in their ability to work towards mitigating the risk of an IMS being translocated to and negatively impacting the unique and diverse ecology of the marine systems, and the industries, people and customs that rely on the coastal marine environment for food, recreation and commerce in the Torres Strait.

  18. The Holocene history of Nares Strait: Transition from glacial bay to Arctic-Atlantic throughflow

    Science.gov (United States)

    Jennings, Anne E.; Sheldon, Christina; Cronin, Thomas M.; Francus, Pierre; Stoner, Joseph; Andrews, John

    2011-01-01

    Retreat of glacier ice from Nares Strait and other straits in the Canadian Arctic Archipelago after the end of the last Ice Age initiated an important connection between the Arctic and the North Atlantic Oceans, allowing development of modern ocean circulation in Baffin Bay and the Labrador Sea. As low-salinity, nutrient-rich Arctic Water began to enter Baffin Bay, it contributed to the Baffin and Labrador currents flowing southward. This enhanced freshwater inflow must have influenced the sea ice regime and likely is responsible for poor calcium carbonate preservation that characterizes the Baffin Island margin today. Sedimentologic and paleoceanographic data from radiocarbon-dated core HLY03-05GC, Hall Basin, northern Nares Strait, document the timing and paleoenvironments surrounding the retreat of waning ice sheets from Nares Strait and opening of this connection between the Arctic Ocean and Baffin Bay. Hall Basin was deglaciated soon before 10,300 cal BP (calibrated years before present) and records ice-distal sedimentation in a glacial bay facing the Arctic Ocean until about 9,000 cal BP. Atlantic Water was present in Hall Basin during deglaciation, suggesting that it may have promoted ice retreat. A transitional unit with high ice-rafted debris content records the opening of Nares Strait at approximately 9,000 cal BP. High productivity in Hall Basin between 9,000 and 6,000 cal BP reflects reduced sea ice cover and duration as well as throughflow of nutrient-rich Pacific Water. The later Holocene is poorly resolved in the core, but slow sedimentation rates and heavier carbon isotope values support an interpretation of increased sea ice cover and decreased productivity during the Neoglacial period.

  19. Seasonal variability of phytoplankton fluorescence in relation to the Straits of Messina (Sicily) tidal upwelling

    Science.gov (United States)

    Azzaro, F.; Decembrini, F.; Raffa, F.; Crisafi, E.

    2007-10-01

    In the Straits of Messina, large gradients of tidal displacements, as well as the topographic constrictions, determine the upwelling of deeper waters in the surface layer. This work describes the seasonal variability in the surface distribution of phytoplankton biomass depending on the upwelling phenomena. Temperature, salinity, nitrates and phytoplankton fluorescence were measured in 1994 and 1995 by continuous underway surface real-time measurements onboard dedicated research boats. Each survey was performed following the dynamic phases of flooding and ebbing tides. Tidal currents are essentially southward during high tide and northward during low tide. During the low water slack tide, large spatial gradients of physical-chemical and biological parameters were found, while at the high water slack tide, a diffused phytoplankton fluorescence was observed only in autumn due to a seasonal thermocline. Salinity, nitrate and chlorophyll-a fluorescence data revealed a significant positive intercorrelation, whereas they were inversely correlated with temperature. Generally, the upwelling distribution was limited to narrow zones during winter, while in summer it was found in the middle of the Straits and in the southern zones. During spring in the southern zone of the Straits, the maximum chlorophyll-a fluorescence was detected (May 1995, 0.32 μg-Chla l-1); in summer, when back and forth tidal movements between the Tyrrhenian and the Ionian seas intensify, decreased values were observed throughout the study area. The data set obtained through continuous and repeatable samplings has allowed the study of different time-space scales in the Straits of Messina, a very strong and dynamic environment. The Straits system could be compared to an "intermittent pump" which, during the different seasons, initially enriches itself and subsequently provides nutrients to the surrounding basins.

  20. Sediment quality in depositional areas of Shelikof Strait and outermost Cook Inlet, July 1997 - July 1998 (NCEI Accession 0000702)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Minerals Management Service (MMS) program "Sediment Quality in Depositional Areas of Shelikof Strait and Outermost Cook Inlet," consisted of a two-year study...

  1. Derelict Gear - Impacts of derelict fishing gear on marine fauna in Puget Sound and the Northwest Straits

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Puget Sound and the Northwest Straits have experienced a long history of commercial fishing activity. Although much of this fishing activity no longer takes place,...

  2. Volume transport data from a submarine cable in the Florida Strait from 1982 to 1998 (NODC Accession 0087879)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Daily mean volume transport data of the Florida Current collected with a submarine cable spanning from South Florida to the Grand Bahama Island in the Florida Strait...

  3. Taxonomy and distribution of benthic foraminifera from the sediments of Palk Strait, Tamil Nadu, east coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Gandhi, S.; Rajamanickam, G.V.; Nigam, R.

    A systematic study of benthic foraminifera has been made on 42 sediment samples collected between Mandapam and Kodiyakkarai, off Palk Strait, Tamil Nadu, India. A total of 102 benthic foraminiferal species belonging to 52 genera, 38 families, 23...

  4. Anthropogenic and natural CO2 exchange through the Strait of Gibraltar

    Directory of Open Access Journals (Sweden)

    J. Ruíz

    2009-04-01

    Full Text Available The exchange of both anthropogenic and natural inorganic carbon between the Atlantic Ocean and the Mediterranean Sea through Strait of Gibraltar was studied for a period of two years under the frame of the CARBOOCEAN project. A comprehensive sampling program was conducted, which was design to collect samples at eight fixed stations located in the Strait in successive cruises periodically distributed through the year in order to ensure a good spatial and temporal coverage. As a result of this monitoring, a time series namely GIFT (GIbraltar Fixed Time series has been established, allowing the generation of an extensive data set of the carbon system parameters in the area. Data acquired during the development of nine campaigns were analyzed in this work. Total inorganic carbon concentration (CT was calculated from alkalinity-pHT pairs and appropriate thermodynamic relationships, with the concentration of anthropogenic carbon (CANT being also computed using two methods, the ΔC* and the TrOCA approach. Applying a two-layer model of water mass exchange through the Strait and using a value of −0.85 Sv for the average transport of the outflowing Mediterranean water recorded in situ during the considered period, a net export of inorganic carbon from the Mediterranean Sea to the Atlantic was obtained, which amounted to 25±0.6 Tg C yr−1. A net alkalinity output of 16±0.6 Tg C yr−1 was also observed to occur through the Strait. In contrast, the Atlantic water was found to contain a higher concentration of anthropogenic carbon than the Mediterranean water, resulting in a net flux of CANT towards the Mediterranean basin of 4.20±0.04 Tg C yr−1 by using the ΔC* method, which constituted the most adequate approach for this environment. A carbon balance in the Mediterranean was assessed and fluxes through the Strait are discussed in relation to the highly diverse estimates available in the literature for the area and the different approaches

  5. An overview of the theta - S correlations in Fram Strait based on the MIZEX 84 data

    Directory of Open Access Journals (Sweden)

    Pawel Schlichtholz

    2002-06-01

    Full Text Available The water masses in Fram Strait have been analyzed on the basis of hydrographic casts taken in summer 1984 during the MIZEX 84 experiment. In particular, theta-S diagrams for 16 areas, each 5o in longitude and 1o in latitude, covering the strait from 77oN to 81oN are used to characterize the water masses and discuss their possible origin. Near the surface, the East Greenland Polar Front clearly separates the lighter, cold and fresh Polar Water (PW from the heavier, warm and saline Atlantic Water (AW. In the upper ocean, the data show a large spreading of the temperature maximum in the theta-S space associated with different modes of the AW recirculating southward below the PW. Two geographically distinct salinity minima are found in the intermediate layer below the AW. The denser one, in the Boreas Basin, is a feature typical of the Arctic Intermediate Water (AIW formed by winter convection to the south of the strait, while the lighter one is sandwiched in the Arctic Ocean outflow between the AW layer and the Upper Polar Deep Water (UPDW characterized by a downward salinity increase. In the deep layer, two salinity maxima are present. The shallower (and warmer one, associated with the Canadian Basin Deep Water (CBDW, appears all along the East Greenland Slope. A similar but weaker maximum is also found in the southeastern part of the strait. This maximum is perhaps a remnant of the maximum in the East Greenland Current after it has been recirculated back to the strait around the cyclonic gyres of the Nordic Seas. The deeper one appears typically as a near-bottom salinity jump characteristic of the Eurasian Basin Deep Water (EBDW. The jump is found in two distinct areas of the strait, to the north-west in the Lena Trough and to the south-east in the rift valley of the Knipovich Ridge. The maximum in the former area should have been advected from the Arctic Ocean below the CBDW, while the maximum in the latter area might have originated from

  6. Impact of Moving Westward on the Economic and Cultural Development of Hetao Area%走西口对河套地区经济文化发展的影响

    Institute of Scientific and Technical Information of China (English)

    李欢; 张磊

    2012-01-01

    As the large-scale immigration process in modern Chinese history, the movements of moving westward created a huge impact on agriculture which was based on a single animal husbandry, promoted the integration of agriculture and animal husbandry, and strengthened complementary of animal husbandry and farming between mainland China and foreign countries. The difference before and after the movement of moving westward was discussed from several aspects of reclaim process, land system and population growth. At last, the far-reaching impact on the economic and cultural development of Hetao caused by the movement of moving westward was pointed out.%走西口作为我国近代史上规模宏大的移民进程,对河套地区以单一牧业经济为基础的农牧业体系形成了巨大冲击,同时也促进了农业与牧业的融合,加强了内地与口外的农牧互补.从垦荒进程、土地制度、人口增长几个方面对比了走西口前后的差异,指出走西口对河套地区经济文化发展产生了深远影响.

  7. Comparison of seasonal variability of Aquarius sea surface salinity time series with in situ observations in the Karimata Strait, Indonesia

    Science.gov (United States)

    Susanto, R. D.; Setiawan, A.; Zheng, Q.; Sulistyo, B.; Adi, T. R.; Agustiadi, T.; Trenggono, M.; Triyono, T.; Kuswardani, A.

    2016-12-01

    The seasonal variability of a full lifetime of Aquarius sea surface salinity time series from August 25, 2011 to June 7, 2015 is compared to salinity time series obtained from in situ observations in the Karimata Strait. The Karimata Strait plays dual roles in water exchange between the Pacific and the Indian Ocean. The salinity in the Karimata Strait is strongly affected by seasonal monsoon winds. During the boreal winter monsoon, northwesterly winds draws low salinity water from the South China Sea into the Java Sea and at the same time, the Java Sea receives an influx of the Indian Ocean water via the Sunda Strait. The Java Sea water will reduce the main Indonesian throughflow in the Makassar Strait. Conditions are reversed during the summer monsoon. Low salinity water from the South China Sea also controls the vertical structure of water properties in the upper layer of the Makassar Strait and the Lombok Strait. As a part of the South China Sea and Indonesian Seas Transport/Exchange (SITE) program, trawl resistance bottom mounted CTD was deployed in the Karimata Strait in mid-2010 to mid-2016 at water depth of 40 m. CTD casts during the mooring recoveries and deployments are used to compare the bottom salinity data. This in situ salinity time series is compared with various Aquarius NASA salinity products (the level 2, level 3 ascending and descending tracks and the seven-days rolling averaged) to check the consistency, correlation and statistical analysis. The preliminary results show that the seasonal variability of Aquarius salinity time series has larger amplitude variability compared to that of in situ data.

  8. Contrasting optical properties of surface waters across the Fram Strait and its potential biological implications

    DEFF Research Database (Denmark)

    Pavlov, Alexey K.; Granskog, Mats A.; Stedmon, Colin A.

    2015-01-01

    radiation (PAR, 400-700nm), but does result in notable differences in ultraviolet (UV) light penetration, with higher attenuation in the EGC. Future changes in the Arctic Ocean system will likely affect EGC through diminishing sea-ice cover and potentially increasing CDOM export due to increase in river......Underwater light regime is controlled by distribution and optical properties of colored dissolved organic matter (CDOM) and particulate matter. The Fram Strait is a region where two contrasting water masses are found. Polar water in the East Greenland Current (EGC) and Atlantic water in the West...... Spitsbergen Current (WSC) differ with regards to temperature, salinity and optical properties. We present data on absorption properties of CDOM and particles across the Fram Strait (along 79° N), comparing Polar and Atlantic surface waters in September 2009 and 2010. CDOM absorption of Polar water in the EGC...

  9. An operative lagrangian model for simulating radioactivity dispersion in the Strait of Gibraltar.

    Science.gov (United States)

    Periáñez, R

    2005-01-01

    GISPART (GIbraltar Strait PARticle Tracking model) is a three-dimensional particle tracking code to simulate the dispersion of radionuclides in the Strait of Gibraltar. It consists of a hydrodynamic module that is run off-line to determine tidal constants and residuals in the domain. This information is stored in several files that are read by the dispersion module to reconstruct water movements. The dispersion module uses a lagrangian approach. Thus, a radionuclide release is simulated by a number of particles, whose paths are computed individually. Radionuclide concentrations are obtained from the density of particles per water volume unit. Some examples of results are shown. The model is also available on-line.

  10. Spatial and temporal variations of Synechococcus and picoeukaryotes in the Taiwan Strait, China

    Institute of Scientific and Technical Information of China (English)

    HUANG Bangqin; LIN Xueju; HONG Huasheng

    2009-01-01

    The size-fractionated phytoplankton biomass, and the spatial and temporal variations in abundance of Synechococcus (SYN) and picoeukaryotes (PEUK) were measured in the Taiwan Strait during three cruises (August 1997, February-March 1998, and August 1998). The results show that picophytoplankton and nanophytoplankton dominate the phytoplankton biomass, in average of 38% and 40%, respectively. SYN and PEUK varied over time in abundance and carbon biomass, greater in summer than in winter, in range of (7.70-209.2)×106 and (0.75-15.4)×106 cells/cm2 in the abundance, and 1.93-52.3 and 1.57-32.4 mgC/cm2 in the carbon biomass, for SYN and PEUK, respectively. The horizontal distributions of both groups were diurnal but heterogeneous in abundance, depending on the groups and layer of depths. Temperature is the key controlling factor for picophytoplankton distribution (especially in winter) in the Strait.

  11. Effect of the Northern Sea Route Opening to the Shipping Activities at Malacca Straits

    Directory of Open Access Journals (Sweden)

    N.S.F. Abdul Rahman

    2014-12-01

    Full Text Available The opening of the Northern Sea Route as an alternative route for transporting cargoes between the Far East and Europe seems highly acceptable by shipping companies due to the great saving in fuel consumption, bunker cost, operating cost, emissions and journey time. This situation will not only affect the maritime business activity in the Straits of Malacca but also, the Malaysian economy in different perspectives when the vessels sail via the Suez Canal and the Indian Ocean are expected to decrease. The objective of this study is to analyse the implication in the opening of the Northern Sea Route on Maritime Sector of the Malaysian economy by using PESTEL analysis. The main scope is focusing more on the Malacca Straits shipping activity by using a number of parameters that have been obtained from Port Klang and Port Klang Authority through a set of questionnaires and interview sessions with industrial experts.

  12. Weathering the empire: meteorological research in the early British Straits Settlements.

    Science.gov (United States)

    Williamson, Fiona

    2015-09-01

    This article explores meteorological interest and experimentation in the early history of the Straits Settlements. It centres on the establishment of an observatory in 1840s Singapore and examines the channels that linked the observatory to a global community of scientists, colonial officers and a reading public. It will argue that, although the value of overseas meteorological investigation was recognized by the British government, investment was piecemeal and progress in the field often relied on the commitment and enthusiasm of individuals. In the Straits Settlements, as elsewhere, these individuals were drawn from military or medical backgrounds, rather than trained as dedicated scientists. Despite this, meteorology was increasingly recognized as of fundamental importance to imperial interests. Thus this article connects meteorology with the history of science and empire more fully and examines how research undertaken in British dependencies is revealing of the operation of transnational networks in the exchange of scientific knowledge.

  13. Support to oil spill emergencies in the Bonifacio Strait, western Mediterranean

    Science.gov (United States)

    Cucco, A.; Ribotti, A.; Olita, A.; Fazioli, L.; Sorgente, B.; Sinerchia, M.; Satta, A.; Perilli, A.; Borghini, M.; Schroeder, K.; Sorgente, R.

    2012-07-01

    An innovative forecasting system of the coastal marine circulation has been implemented in the Bonifacio Strait area, between Corsica and Sardinia, using a numerical approach to facilitate the rapid planning and coordination of remedial actions for oil spill emergencies at sea by local authorities. Downscaling and nesting techniques from regional to coastal scale and a 3-D hydrodynamic numerical model, coupled with a wind wave model, are the core of the integrated Bonifacio Strait system. Such a system is capable of predicting operationally the dispersion of hydrocarbon spills in the area, both in forward and backward mode, through an easy-to-use graphical user interface. A set of applications are described and discussed including both operational applications aimed at providing rapid responses to local oil spill emergences and managing applications aimed at mitigating the risk of oil spill impacts on the coast.

  14. Prospect for Petroleum Industry Exchange & Cooperation Between Bath Sides of Taiwan Strait

    Institute of Scientific and Technical Information of China (English)

    Wu Xunyue; HUO Fu

    1996-01-01

    @@ With the First Conference of the Petroleum Science and Technology between both sides of the Taiwan Straits successfully held in Taiwan last year, the exchange and cooperation in the petroleum industry between both sides has made the first step forward. The Chinese nation is an outstanding nation. To gain a floor for China in the world,both sides of the Straits must, on the premise of mutual complement and mutual benefit, strengthen their mutual exchange and cooperation as well as the trade contacts so as to promote their common prosperity. This point was a common understanding in the discussion of Mr. Chang Tzu-yuan, Chairman of Chinese Petroleum Corporation (CPC) and China National Petroleum Corporation (CNPC).This belief is further strengthened, when Mr. Chang Tzuyuan came to the mainland as a return visit in midNovember 1995.

  15. Zooplankton distribution across Fram Strait in autumn: Are small copepods and protozooplankton important?

    Science.gov (United States)

    Svensen, Camilla; Seuthe, Lena; Vasilyeva, Yulia; Pasternak, Anna; Hansen, Edmond

    2011-12-01

    We investigated zooplankton distribution in September 2006/2007 at eight stations across Fram Strait in contrasting water masses ranging from cold Polar water to warm Atlantic water. Our main objectives were: (1) to describe the plankton community in the upper 200 m during autumn, and (2) to investigate the importance of small-sized copepods and protozooplankton in an arctic ecosystem when the majority of the large Calanus species had entered diapause. We sampled both with a WP-2 net and Go-Flo bottle and show that small copepods food. Heterotrophic protozooplankton, on the other hand, were most likely bottom-up regulated by the availability of phytoplankton food and conclude that there was a strong link between the zooplankton community and the microbial food web in Fram Strait.

  16. Recent transient tracer distributions in the Fram Strait: estimation of anthropogenic carbon content and transport

    Directory of Open Access Journals (Sweden)

    T. Stöven

    2015-09-01

    Full Text Available The storage of anthropogenic carbon in the ocean's interior is an important process which modulates the increasing carbon dioxide concentrations in the atmosphere. The polar regions are expected to be net sinks for anthropogenic carbon. Transport estimates of dissolved inorganic carbon and the anthropogenic offset can thus provide information about the magnitude of the corresponding storage processes. Here we present a transient tracer, dissolved inorganic carbon (DIC and total alkalinity (TA data set along 78°50′ N sampled in the Fram Strait in 2012. A theory on tracer relationships is introduced which allows for an application of the Inverse Gaussian – Transit Time Distribution (IG-TTD at high latitudes and the estimation of anthropogenic carbon concentrations. Current velocity measurements along the same section were used to estimate the net flux of DIC and anthropogenic carbon through the Fram Strait. The new theory explains the differences between the theoretical (IG-TTD based tracer age relationship and the specific tracer age relationship of the field data by saturation effects during water mass formation and/or the deliberate release experiment of SF6 in the Greenland Sea in 1996 rather than by different mixing or ventilation processes. Based on this assumption, a maximum SF6 excess of 0.5–0.8 fmol kg−1 was determined in the Fram Strait at intermediate depths (500–1600 m. The anthropogenic carbon concentrations are 50–55 μmol kg−1 in the Atlantic Water/Recirculating Atlantic Water, 40–45 μmol kg−1 in the Polar Surface Water/warm Polar Surface Water and between 10–35 μmol kg−1 in the deeper water layers, with lowest concentrations in the bottom layer. The net DIC and anthropogenic carbon fluxes through the Fram Strait indicate a balanced exchange between the Arctic Ocean and the North Atlantic, although with high uncertainties.

  17. The Application of Fucus vesiculosus as a Bioindicator of 60Co Concentrations in the Danish Straits

    DEFF Research Database (Denmark)

    Boelskifte, S.

    1985-01-01

    The occurrence of 60Co in the Danish Straits is investigated by applying the seaweed Fucus vesiculosus as a bioindicator. In order to describe different dispersion situations, three areas have been studied separately: the North Sea, where it is possible to measure 60Co from sources in France and...... of distance from Barsebäck. Problems of uncertainty related to differences in environmental parameters are discussed and new investigations to improve the use of Fucus as a bioindicator are suggested....

  18. Numerical simulation of marine currents in the Bunaken Strait, North Sulawesi, Indonesia

    Science.gov (United States)

    Rompas, P. T. D.; Manongko, J. D. I.

    2016-04-01

    This study intended for the generation of hydroelectric power at suitable area of the strait in order to provide electric current to a close environment. The project uses a three-dimensional model of taking flow into account the variation of hydrostatic pressure in the liquid vertical layers. We brought back to a two-dimensional calculation using the shallow water equations. The objectives of the study are getting simultaneous obtaining the velocities of currents by the component of velocities and distributions of the kinetic energy from the numerical results. The Bunaken strait is 5280 m width for an average depth of 130 m. Numerical calculation is simulated using horizontal meshes of 60 side meters. The numerical solutions obtained by using a time step of one second. It found that there was no great difference between 2D and 3D numerical simulations because the effect of flow velocity in the vertical direction is very small. The numerical results have shown that the average current velocities when low and high tide currents are 1.46 m/s and 0.85 m/s respectively. The kinetic energy ranged from 0.01 to 2.54 kW/m2 when low and high tide in the Bunaken strait area at discharge of 1 Sv, whereas at discharge 2 Sv, 0.11-17.40 kW/m2 and 0.11-2.77 kW/m2 (when low and high tide currents). These results can used in the design of turbines for power generation marine currents in the Bunaken strait at depths below 60 meters.

  19. 77 FR 55452 - Lynn Canal-Icy Strait Resource Advisory Committee

    Science.gov (United States)

    2012-09-10

    ...The Lynn Canal-Icy Strait Resource Advisory Committee (LC-IS RAC) will meet in Juneau, AK. The committee is authorized under the Secure Rural Schools and Community Self-Determination Act (Pub. L. 112- 141) (the Act) and operates in compliance with the Federal Advisory Committee Act. The purpose of the committee is to improve collaborative relationships and to provide advice and recommendations......

  20. Development of Seismic Demand for Chang-Bin Offshore Wind Farm in Taiwan Strait

    OpenAIRE

    Yu-Kai Wang; Juin-Fu Chai; Yu-Wen Chang; Ti-Ying Huang; Yu-Shu Kuo

    2016-01-01

    Taiwan is located on the Pacific seismic belt, and the soil conditions of Taiwan’s offshore wind farms are softer than those in Europe. To ensure safety and stability of the offshore wind turbine supporting structures, it is important to assess the offshore wind farms seismic forces reasonably. In this paper, the relevant seismic and geological data are obtained for Chang-Bin offshore wind farm in Taiwan Strait, the probabilistic seismic hazard analysis (PSHA) is carried out, and the first un...

  1. Recent transient tracer distributions in the Fram Strait: estimation of anthropogenic carbon content and transport

    Science.gov (United States)

    Stöven, T.; Tanhua, T.; Hoppema, M.; von Appen, W.-J.

    2015-09-01

    The storage of anthropogenic carbon in the ocean's interior is an important process which modulates the increasing carbon dioxide concentrations in the atmosphere. The polar regions are expected to be net sinks for anthropogenic carbon. Transport estimates of dissolved inorganic carbon and the anthropogenic offset can thus provide information about the magnitude of the corresponding storage processes. Here we present a transient tracer, dissolved inorganic carbon (DIC) and total alkalinity (TA) data set along 78°50' N sampled in the Fram Strait in 2012. A theory on tracer relationships is introduced which allows for an application of the Inverse Gaussian - Transit Time Distribution (IG-TTD) at high latitudes and the estimation of anthropogenic carbon concentrations. Current velocity measurements along the same section were used to estimate the net flux of DIC and anthropogenic carbon through the Fram Strait. The new theory explains the differences between the theoretical (IG-TTD based) tracer age relationship and the specific tracer age relationship of the field data by saturation effects during water mass formation and/or the deliberate release experiment of SF6 in the Greenland Sea in 1996 rather than by different mixing or ventilation processes. Based on this assumption, a maximum SF6 excess of 0.5-0.8 fmol kg-1 was determined in the Fram Strait at intermediate depths (500-1600 m). The anthropogenic carbon concentrations are 50-55 μmol kg-1 in the Atlantic Water/Recirculating Atlantic Water, 40-45 μmol kg-1 in the Polar Surface Water/warm Polar Surface Water and between 10-35 μmol kg-1 in the deeper water layers, with lowest concentrations in the bottom layer. The net DIC and anthropogenic carbon fluxes through the Fram Strait indicate a balanced exchange between the Arctic Ocean and the North Atlantic, although with high uncertainties.

  2. Using Metasynthesis to Develop Sensitising Concepts to Understand Torres Strait Islander Migration

    Directory of Open Access Journals (Sweden)

    Vinnitta Patricia Mosby

    2013-03-01

    Full Text Available Emerging research indicates that more and more Indigenous peoples will be forced to migrate due to climate change. Current responses focus on mitigation and adaptation strategies. One such group, Torres Strait Islander people are already moving for other reasons and existing vulnerabilities compound levels of disadvantage when moving. It will be important to understand Torres Strait Islander people’s experiences of contemporary movements in order to inform policy development and facilitate the process of migration and resettlement as movement increases. A synthesis of existing studies would allow the development of sensitising concepts that could inform future research in the Torres Strait Islander context. This article presents a metasynthesis of six qualitative studies of the experiences of different Indigenous and minority groups at various stages of migration, displacement and resettlement. Articles were selected on contemporary movements (2001-2011 and importantly the inclusion of first person voice. Reciprocal translation was used to synthesise common themes and a core construct. The overarching construct that became apparent from the metasynthesis was ‘continuity of being’ through staying connected to self, family and culture. Three themes emerged: ‘freedom to be’, ‘staying close’ and ‘forming anchor’. These were enacted through people valuing their personal, social, religious and political freedom and recognising the importance of maintaining or forming strong social and family networks. When researching the experiences of Torres Strait Islanders it will be necessary to focus on motivations for moving, and understand the processes for staying connected to kin and homeland in order to achieve the desired outcomes of successful resettlement under conditions of uncertainty.

  3. Riau vegetables for Singapore consumers: A collaborative knowledge transfer project across the Straits of Malacca

    OpenAIRE

    Menkhoff, Thomas; Loh, Patrick H. M.; Bin, Chua Sin; Evers, Hans-Dieter; Chay, Yue Wah

    2007-01-01

    The paper analyses a recent collaborative knowledge transfer project between the Republic of Singapore and the Republic of Indonesia across the Straits of Malacca. The initiative was aimed at supplying the city state at the southern tip of the Malay Peninsula with green vegetables from Riau, Indonesia, and to provide technical assistance to Riau farmers on protected cultivation and post-harvest technologies. We reconstruct the bilateral evolution of the vegetable project in the context of the...

  4. Observations on the Characteristics of the Exchange Flow in the Daranelles Strait

    Science.gov (United States)

    2012-11-09

    North Atlantic Treaty Organization (NATO) Under- sea Research Center ( NURC ) in collaboration with the Turkish Navy Office of Navigation, Hydrography...from the R/V Alliance (a NATO NURC research vessel) as a part of TSS08 ( NURC project) and “Exchange Processes in Ocean Straits” (EPOS, NRL project...research project “Exchange Processes in Ocean Straits (EPOS)” under Program Element 61153N. We would like to thank everyone from the NATO NURC and the

  5. Regional Stratification and Shear of the Various Streams Feeding the Philippine Straits - ESR Component

    Science.gov (United States)

    2016-06-13

    Regional Stratification and Shear of the Various Streams Feeding the Philippine Straits – ESR Component Amy Ffield Earth & Space Research , 290...N0001406C0578 http://www.esr.org LONG-TERM GOALS To determine the impact of the regional oceanographic and atmospheric mean and variable ...Surface Temperature: Analysis of the OI Infrared Satellite SST reveals that the SST in the Philippine Archipelago region has significant variability

  6. Options for managing the sustainable use of green turtles: Perceptions of Hammond Islanders in Torres Strait

    Directory of Open Access Journals (Sweden)

    Grayson Jillian

    2010-01-01

    Full Text Available One of the largest populations of green turtles (Chelonia mydas in the world spends at least part of its life cycle in the remote Torres Strait between Australia and Papua New Guinea. This population is subjected to traditional harvests from geographically dispersed communities including along the northern and eastern coasts of Australia, Indonesia and south-western Pacific nations. In Torres Strait, green turtle hunting is classed as a traditional fishery and is guaranteed by Australian legislation (Native Title Act 1993 and the Torres Strait Treaty between Australia and Papua New Guinea that aims to protect the traditional lifestyle of the region′s indigenous peoples. To investigate the Islanders′ thoughts and aspirations regarding marine turtle management, we interviewed hunters and Islander Elders from the Hammond Island community in the Kaurareg nation of Kaiwalagal. Although not the Traditional Owners of the Kaiwalagal sea country in which they live and hunt, Hammond Islanders wish to be involved in the management of resources on which they depend, including marine turtles. They considered community-based processes to be important, especially the application of (1 cultural norms to the development of tools to achieve compliance and enforcement within the community, and (2 consensus-based decision-making amongst hunters and elders within the community, with regard to the use of more formal rules. However, the need for co-operation with other communities and stakeholders across scales was also recognised, particularly with regard to enforcement. Our results suggest that co-management is likely to be a more appropriate approach for managing green turtles in Torres Strait than either community-based management or government-driven management.

  7. Enforcing Ship-Based Marine Pollution for Cleaner Sea in the Strait of Malacca

    Directory of Open Access Journals (Sweden)

    Sutarji Kasmin

    2010-01-01

    Full Text Available The Strait of Malacca is most susceptible to ship-based marine pollution such as oil and grease due to the heavy volume of shipping in the Strait. By nature, oil is toxic to marine life, especially the polycyclic aromatic hydrocarbons (PAHs, one of the main components in crude oil that is very difficult to clean up, and could remain for years in the sediment and marine environment. Marine species that are constantly exposed to PAHs can exhibit developmental problems and are more susceptible to diseases. The number of ships passing through the Strait in 2000 was 55,957 and increased to 62,621 ships 5 years later. In 2007, the traffic volume increased to 70,718 ships. During the five-year period from 2000 to 2005, there were 144 cases of oil spills into the sea. One hundred eight cases were due to illegal discharge of dirty oil. However, only 32 ships were charged and subsequently, 14 ships were found guilty. This paper analyses the challenges faced by the Malaysian maritime enforcement agencies in enforcing the Environmental Quality Act 1974 in the Strait of Malacca. Some of these challenges relate to the maritime enforcement agencies’ short-comings, nature of the Strait’s users and the legal processes to bring offenders to court. Based on the analyses, it was revealed that the responsible agencies are inadequately equipped and trained to deal with the illegal discharge of dirty oil into the sea. In order to overcome these weaknesses, several new initiatives are suggested.

  8. Population biology of coral trout species in eastern Torres Strait: Implications for fishery management

    Science.gov (United States)

    Williams, Ashley J.; Currey, Leanne M.; Begg, Gavin A.; Murchie, Cameron D.; Ballagh, Aaron C.

    2008-09-01

    Coral trout ( Plectropomus spp.) are the main target species for commercial fishers in the eastern Torres Strait Reef Line Fishery (ETS RLF). The four species of coral trout known to occur in Torres Strait: Plectropomus leopardus, Plectropomus maculatus, Plectropomus areolatus and Plectropomus laevis are currently managed as a single species in Torres Strait, as there is no species-specific biological information available for the region which could be used to assess whether species differ in their response to fishing pressure. The aim of our study was to determine whether it is appropriate (biologically) to manage coral trout in the ETS RLF as a single species group or whether different management arrangements are required for some species. We used catch data and biological data from samples collected by commercial fishers to examine the distribution within Torres Strait and estimate a range of biological parameters for P. leopardus, P. maculatus and P. areolatus. Insufficient P. laevis samples were collected to reliably examine this species. Results indicated that the population biology, particularly the reproductive biology, of P. areolatus was substantially different to both P. leopardus and P. maculatus. Although it is difficult to predict the response to fishing, P. areolatus may be more vulnerable to fishing than P. leopardus and P. maculatus, due to the larger size at sex change observed for this species and the very low proportion of males protected by the current minimum size limit. Therefore, while the common management arrangements for P. leopardus and P. maculatus appear to be adequate for these species, separate management arrangements are needed for the sustainable harvest of P. areolatus populations in the ETS. Specifically, we recommend the introduction of a maximum size limit for P. areolatus, in addition to the current minimum size limit, which may allow a proportion of males some protection from fishing.

  9. "Dancing with the stars" - astronomy and music in the Torres Strait

    CERN Document Server

    Hamacher, Duane W

    2016-01-01

    Song and dance are a traditional means of strengthening culture and passing knowledge to successive generations in the Torres Strait of northeastern Australia. Dances incorporate a range of apparatuses to enhance the performance, such as dance machines (Zamiyakal) and headdresses (Dhari). The dances, songs, headdresses and dance machines work together to transfer important knowledge about subsistence survival, social structure, and cultural continuity. This paper explores how celestial phenomena inspire and inform music and dance.

  10. Port and Waterway Safety Assessment: Haro Strait/Boundary Pass USA - Canada Workshop Report

    Science.gov (United States)

    2002-02-26

    Strait. Small vessel operator certifications are highly regulated by Transport Canada. USA tug operators are certified. Crew is STCW certificated...Deep-sea fleet is regulated by PSC. For Alaskan fishing vessels, 90% have STCW certificates on vessels of 200 gross tons and larger. All...Canadian tugboat deck officers are certified in accordance with STCW . In some cases, there are two pilots on 40,000 DWT tankers when transiting (Canada

  11. Development of a Hydrodynamic Model of Puget Sound and Northwest Straits

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Zhaoqing; Khangaonkar, Tarang P.

    2007-12-10

    The hydrodynamic model used in this study is the Finite Volume Coastal Ocean Model (FVCOM) developed by the University of Massachusetts at Dartmouth. The unstructured grid and finite volume framework, as well as the capability of wetting/drying simulation and baroclinic simulation, makes FVCOM a good fit to the modeling needs for nearshore restoration in Puget Sound. The model domain covers the entire Puget Sound, Strait of Juan de Fuca, San Juan Passages, and Georgia Strait at the United States-Canada Border. The model is driven by tide, freshwater discharge, and surface wind. Preliminary model validation was conducted for tides at various locations in the straits and Puget Sound using National Oceanic and Atmospheric Administration (NOAA) tide data. The hydrodynamic model was successfully linked to the NOAA oil spill model General NOAA Operational Modeling Environment model (GNOME) to predict particle trajectories at various locations in Puget Sound. Model results demonstrated that the Puget Sound GNOME model is a useful tool to obtain first-hand information for emergency response such as oil spill and fish migration pathways.

  12. Domesticating Hybridity: Straits Chinese Cultural Heritage Projects in Malaysia and Singapore

    Directory of Open Access Journals (Sweden)

    Karen M. Teoh

    2015-12-01

    Full Text Available This article examines the literal and figurative domestication of Straits Chinese, or Peranakan, history in selected heritage projects in late twentieth-century Malaysia and Singapore. These projects simultaneously foreground Straits Chinese history as a symbol of interracial harmony and marginalize it as a cultural artifact. Over the late nineteenth and twentieth centuries, the ethnoculturally hybrid Straits Chinese positioned themselves as “the King’s Chinese,” champions of a Confucian-values renaissance, and citizens of independent Malaysia and Singapore. Their adaptability helped them survive the upheaval of imperialism, decolonization, and nation building, but it was also controversial for its suggestion of political flexibility. Today, Southeast Asian governments and the Peranakan themselves depict the community as a uniquely local model of ethnic integration. Museums and historic homes emphasize portrayals and consumption of supposedly feminine aspects of Peranakan culture (e.g., fashion and cuisine, while downplaying purportedly masculine elements (e.g., the possession of multiple nationalities. By conflating femininity, tradition, and racial hybridity, this approach reifies stereotypes about gender and cultural identity, and replaces transgressive potential with politically anodyne nostalgia and commercialization. As anxieties about race, national history, and belonging continue to undergird the modern polity, transnationalism and transculturalism are acceptable as long as they are confined to the past.

  13. Social Exclusion/Inclusion for Urban Aboriginal and Torres Strait Islander People

    Directory of Open Access Journals (Sweden)

    Maggie Walter

    2016-02-01

    Full Text Available Social exclusion social inclusion are useful concepts for making sense of the deeply embedded socio-economic disadvantaged position of Aboriginal and Torres Islander people in Australian. The concepts not only describe exclusion from social and economic participation; but seek to understand the dynamic processes behind their creation and reproduction. Yet few Australian studies go beyond describing Aboriginal over-representation on social exclusion indicators. Neither do they address the translatability of the concepts from non-Indigenous to Indigenous contexts despite mainstream studies finding the pattern of social exclusion (and therefore what social inclusion might look like differs for Aboriginal and Torres Strait Islander people to that of other disadvantaged groups. This paper uses data from the Longitudinal Study of Indigenous children to explore patterns of social exclusion across social, economic, well-being and community dimensions for urban Aboriginal and Torres Strait families. The paper then develops a contextual understanding of the processes and patterns that create and sustain social exclusion and the opportunities and challenges of moving to greater social inclusion for urban Aboriginal and Torres Strait Islander people/s.

  14. Potential polyunsaturated aldehydes in the Strait of Gibraltar under two tidal regimes.

    Science.gov (United States)

    Morillo-García, Soledad; Valcárcel-Pérez, Nerea; Cózar, Andrés; Ortega, María J; Macías, Diego; Ramírez-Romero, Eduardo; García, Carlos M; Echevarría, Fidel; Bartual, Ana

    2014-03-13

    Diatoms, a major component of the large-sized phytoplankton, are able to produce and release polyunsaturated aldehydes after cell disruption (potential PUAs or pPUA). These organisms are dominant in the large phytoplankton fraction (>10 µm) in the Strait of Gibraltar, the only connection between the Mediterranean Sea and the Atlantic Ocean. In this area, the hydrodynamics exerts a strong control on the composition and physiological state of the phytoplankton. This environment offers a great opportunity to analyze and compare the little known distribution of larger sized PUA producers in nature and, moreover, to study how environmental variables could affect the ranges and potential distribution of these compounds. Our results showed that, at both tidal regimes studied (Spring and Neap tides), diatoms in the Strait of Gibraltar are able to produce three aldehydes: Heptadienal, Octadienal and Decadienal, with a significant dominance of Decadienal production. The PUA released by mechanical cell disruption of large-sized collected cells (pPUA) ranged from 0.01 to 12.3 pmol from cells in 1 L, and from 0.1 to 9.8 fmol cell⁻¹. Tidal regime affected the abundance, distribution and the level of physiological stress of diatoms in the Strait. During Spring tides, diatoms were more abundant, usually grouped nearer the coastal basin and showed less physiological stress than during Neap tides. Our results suggest a significant general increase in the pPUA productivity with increasing physiological stress for the cell also significantly associated to low nitrate availability.

  15. Probabilistic Hazard of Tsunamis Generated by Submarine Landslides in the Cook Strait Canyon (New Zealand)

    Science.gov (United States)

    Lane, Emily M.; Mountjoy, Joshu J.; Power, William L.; Mueller, Christof

    2016-12-01

    Cook Strait Canyon is a submarine canyon that lies within ten kilometres of Wellington, the capital city of New Zealand. The canyon walls are covered with scars from previous landslides which could have caused local tsunamis. Palaeotsunami evidence also points to past tsunamis in the Wellington region. Furthermore, the canyon's location in Cook Strait means that there is inhabited land in the path of both forward- and backward-propagating waves. Tsunamis induced by these submarine landslides pose hazard to coastal communities and infrastructure but major events are very uncommon and the historical record is not extensive enough to quantify this hazard. The combination of infrequent but potentially very consequential events makes realistic assessment of the hazard challenging. However, information on both magnitude and frequency is very important for land use planning and civil defence purposes. We use a multidisciplinary approach bringing together geological information with modelling to construct a Probabilistic Tsunami Hazard Assessment of submarine landslide-generated tsunami. Although there are many simplifying assumptions used in this assessment, it suggests that the Cook Strait open coast is exposed to considerable hazard due to submarine landslide-generated tsunamis. We emphasise the uncertainties involved and present opportunities for future research.

  16. Assessment of Radiation and Heavy Metals Risk due to the Dietary Intake of Marine Fishes (Rastrelliger kanagurta) from the Straits of Malacca

    National Research Council Canada - National Science Library

    Khandaker, M U; Asaduzzaman, Kh; Nawi, S M; Usman, A R; Amin, Y M; Daar, E; Bradley, D A; Ahmed, H; Okhunov, A A

    2015-01-01

    The environment of the Straits of Malacca receives pollution as a result of various industrial and anthropogenic sources, making systematic studies crucial in determining the prevailing water quality...

  17. POSSIBLE ROLE OF CLIMATE CHANGE IN THE MONGOL WESTWARD CONQUESTS%气候变化因素在蒙古西征中的可能作用研究

    Institute of Scientific and Technical Information of China (English)

    吴文祥; 葛全胜; 郑景云; 周扬; 胡莹

    2009-01-01

    13世纪上半叶蒙古帝国发动的3次西征极大地改变了欧亚大陆的政治格局和历史进程,成为世界最为重大历史事件之一;其发生原因一直是学术界关注的焦点,人们提出了各种假说,其中气候变化驱动说,即干旱或/和降温事件触发蒙古西征说最具影响力.文章依据古气候研究进展对蒙古西征的动因进行了重新研究,首先对蒙古西征各种假说进行了回顾,重点介绍和评述了气候变化驱动说,然后根据我国高分辨率气候重建资料,结合欧亚大陆其他地区的古气候重建成果,恢复了蒙古西征时期的气候背景;结果发现蒙古西征并非发生在传统上所认为的干旱或/和降温期,而是发生在相当于中世纪温暖期中的中后期,而且当时蒙古民族主要生活住居地区还比较湿润.研究结果对传统的气候驱动说提出了挑战,认为蒙古西征并非干旱或/和降温事件所触发,相反,当时温暖而湿润的气候环境为蒙古西征提供了良好的物质基础.研究结果较好地解释了蒙古当时征讨的重点地区为什么是西北方而不是东南方的印度和南宋地区之谜.%The first half of the 13th century marks a significant period in the history of Eurasian continent,during which the unprecedented Mongol westward conquests were launched over the Eurasian continent by Chinggis Khan and his tribal members in 1219~1225A.D.,1235~1241A.D.,and 1252~1258A.D.,respectively.These westward conquests not only altered the political structure but also affected the history courses of Eurasian continent,thus being regarded as a milestone and a turning point in the history of Eurasian.At present,many issues related to Mongol westward conquests have been resolved gradually.However,the causes of such massive drives still remains a mystery with some questions for further exploration.For instance,why did Mongol Empire launch three times of westward conquests? Why did the Mongol

  18. 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

  19. STUDY OF CHLOROPHYLL-A DISTRIBUTIONS IN LOMBOK STRAIT USING BIOGEOCHEMICAL MODEL BASED ON REGIONAL OCEAN MODELLING SYSTEM (ROMS

    Directory of Open Access Journals (Sweden)

    KADEK ARY ANGGRAENI

    2015-06-01

    Full Text Available Regional Ocean Modelling System (ROMS has been intended to be a multi-purpose, multi-disciplinary oceanic modeling tool. The Biogeochemical model have coupled to ROMS consists of a system of seven coupled partial differential equations that include: nitrate, ammonium, small and large detritus, phytoplanJ..'ton, zooplankton, and a dynamic phytoplanJ..-ton carbon to chlorophyll ratio. The study of distribution patterns of chlorophyll-a in Lombok Strait (-7 °N - ·10 •sand 114 "E - 117 °E in 2006 was analyzed using the Biogeochemical model based on ROMS. The results show that low chlorophyll-a distributions (0.20 mgChl-a/m3 observed in Lombok Strait in ,January. Chlorophyll-a estimated around the southern part of Bali Strait and low chlorophyll-a distribution in upper layer of the Lomhok Strait. Chlorophyll-a of the booming (0.32 mgChl-a/m3 observed in August. The northeast current direction moves to the west and southern part of research area through Lombok Strait. The highest chlorophyll-a concentration estimated in the northern and southwestern part of Bali Tsland and also in the southern part of Lombok Island. During dry monsoon, southeasterly wind blow from Australia generates upwelling process (low temperature and nutrient-rich water near the surface also estimated from ROMS.

  20. Water exchange between Algeciras Bay and the Strait of Gibraltar: A study based on HF coastal radar

    Science.gov (United States)

    Chioua, J.; Dastis, C.; González, C. J.; Reyes, E.; Mañanes, R.; Ruiz, M. I.; Álvarez, E.; Yanguas, F.; Romero, J.; Álvarez, O.; Bruno, M.

    2017-09-01

    This study analyses the water mass exchanges at subinertial scale between Algeciras Bay and the adjacent Strait of Gibraltar. The mechanisms triggering this exchange process is investigated with the aid of recently-acquired data on surface currents obtained using a system of HF coastal radars deployed on the eastern side of the Strait, and remotely-sensed images of sea surface temperature (SST) and chlorophyll from the MODIS sensor of the Aqua satellite. HF radar data on surface currents are analyzed by the application of real empirical orthogonal function (EOF) decomposition, which produces three EOF modes explaining more than 70% of the variance of the surface currents at the mouth of the Bay (modes 2, 3, and 6). Mode 2 is related to the fluctuations of the Atlantic Jet in the central zone of the Strait, mainly due to a combined effect of the atmospheric pressure fluctuations in the Western Mediterranean Sea and local wind in the eastern side of the Strait; mode 3 is related to the coastal currents induced by zonal wind forcing on the north-western coast of the Strait and Alboran Sea; and mode 6 seems to be related to water transport induced by winds blowing with a significant north component into and out of the Bay.

  1. The Forest Pattern and Its Variation Characteristics in Economic Zone on the Western Coast of the Taiwan Straits

    Institute of Scientific and Technical Information of China (English)

    Juan; TAN; Qing; WANG; Min; WANG; Chenyan; SHA; Junjie; RUAN; Shenfa; HUANG

    2013-01-01

    Taking Economic Zone on the Western Coast of the Taiwan Straits as the study area,we use GIS,remote sensing,mathematical statistics and other methods,to analyze the forest pattern and its variation characteristics in Economic Zone on the Western Coast of the Taiwan Straits during the period 1992-2008;use canonical correspondence analysis(CCA)to examine the effects of environmental factors on changes in forest pattern.The results show that the forest resources are rich in Economic Zone on the Western Coast of the Taiwan Straits,accounting for 61.40% of the total area,but the geographical distribution is very uneven,with obvious regional and elevation gradient difference;since1992,the forest has been dwindling in Economic Zone on the Western Coast of the Taiwan Straits,from 89 300 km2 in 1992 to 88 300 km2 in 2008;in terms of changes in region and elevation gradient,there is obvious difference in the forest,and the central and western forest of Wuyi Mountain tends to decline obviously;the main environmental factors influencing changes in forest pattern in Economic Zone on the Western Coast of the Taiwan Straits include temperature,sunshine hours,GDP per capita and precipitation;evaporation,evaporation and population density have weak effects on changes in forest pattern.

  2. Observed Intraseasonal Oceanic Variations in the Eastern Equatorial Indian Ocean and in the Outflow Straits of the Indonesian Throughflow

    Directory of Open Access Journals (Sweden)

    Iskhaq Iskandar

    2010-09-01

    Full Text Available The observed currents in the eastern equatorial Indian Ocean and in the outflow straits of the Indonesian Throughflow (ITF are shown to have significant intraseasonal variations and coherency during January 2004 – November 2006. The wavelet analysis between the eastern equatorial Indian Ocean and the ITF straits demonstrates significant intraseasonal coherency for the observed current at 50m depth. At 150m depth, the intraseasonal coherency only occurs between the observed currents in the eastern equatorial Indian Ocean and in the Lombok and Ombai Straits. On the other hand, at 350m depth the intraseasonal coherency is only found between the eastern equatorial Indian Ocean and the Ombai Strait. This intraseasonal coherency is associated with the wind-forced equatorial Kelvin waves which propagate eastward along the equatorial and coastal wave guides. Near-surface intraseasonal variations are associated with the first baroclinic mode with typical phase speed of 2.91 ± 0.46 m s-1, while the deeper layer intraseasonal variations are associated with the second baroclinic mode with typical phase speed of 1.59 ± 0.18 m s-1. Moreover, the lag correlations between the zonal winds and the observed currents at the ITF straits further demonstrate the source of intraseasonal variations in the ITF.

  3. Shoaling of internal solitary waves at the ASIAEX site in the South China Sea

    Directory of Open Access Journals (Sweden)

    K. G. Lamb

    2014-07-01

    Full Text Available The interaction of barotropic tides with Luzon Strait topography generates westward propagating internal bores and solitary waves trains which eventually shoal and dissipate on the western side of the South China Sea. Two-dimensional numerical simulations of this shoaling process at the site of the Asian Seas International Acoustic Experiment (ASIAEX have been undertaken in order to investigate the sensitivity of the shoaling process to the stratification and the underlying bathymetry, and to explore the influence of rotation. A range of wave amplitudes are considered. Comparisons with adiabatic shoaling waves are also made and the potential impact of a non-slip boundary condition are briefly explored. On the slope secondary solitary waves and mode-two wave packets are generated which propagate towards the shelf. Comparisons with observations made during the ASIAEX experiment are made.

  4. Liquid export of Arctic freshwater components through the Fram Strait 1998–2011

    Directory of Open Access Journals (Sweden)

    G. Kattner

    2013-01-01

    Full Text Available We estimated the magnitude and composition of southward liquid freshwater transports in the East Greenland Current near 79° N in the Western Fram Strait between 1998 and 2011. Previous studies have found this region to be an important pathway for liquid freshwater export from the Arctic Ocean to the Nordic Seas and the North Atlantic subpolar gyre. Our transport estimates are based on six hydrographic surveys between June and September and concurrent data from moored current meters. We combined concentrations of liquid freshwater, meteoric water (river water and precipitation, sea ice melt and brine from sea ice formation, and Pacific Water, presented in Dodd et al. (2012, with volume transport estimates from an inverse model. The average of the monthly snapshots of southward liquid freshwater transports between 10.6° W and 4° E is 100 ± 23 mSv (3160 ± 730 km3 yr−1, relative to a salinity of 34.9. This liquid freshwater transport consists of about 130% water from rivers and precipitation (meteoric water, 30% freshwater from the Pacific, and −60% (freshwater deficit due to a mixture of sea ice melt and brine from sea ice formation. Pacific Water transports showed the highest variation in time, effectively vanishing in some of the surveys. Comparison of our results to the literature indicates that this was due to atmospherically driven variability in the advection of Pacific Water along different pathways through the Arctic Ocean. Variations in most liquid freshwater component transports appear to have been most strongly influenced by changes in the advection of these water masses to the Fram Strait. However, the local dynamics represented by the volume transports influenced the liquid freshwater component transports in individual years, in particular those of sea ice melt and brine from sea ice formation. Our results show a similar ratio of the transports of meteoric water and net sea ice melt as previous studies. However, we observed a

  5. Study of the Relationship Between the Organizational Climate and the Campus Ethical Issues of Universities across the Taiwan Strait

    Institute of Scientific and Technical Information of China (English)

    WU Chen-fong

    2004-01-01

    The study applied the approach of empirical studies to select 176 teachers in 9 universities in Taiwan and Inland in China to deliver questionnaires. The study intended to explore the influence of organizational climate on campus ethics and its diversity between the universities across the Taiwan strait. The study explored that the organizational climate in the universities across the Strait was not ethically high. Yet, the universities in Inland emphasized more on campus restraint in teachers' behavior, job performance and their sense of belonging to the school.The study result demonstrated that improving leadership of the universities could enhance teachers' identification with their schools and could promote the level of campus across the Strait.

  6. Recent summer sea ice thickness surveys in the Fram Strait and associated volume fluxes

    Directory of Open Access Journals (Sweden)

    T. Krumpen

    2015-09-01

    Full Text Available Fram Strait is the main gateway for sea ice export out of the Arctic Ocean, and therefore observations there give insight into composition and properties of Arctic sea ice in general and how it varies over time. An extensive data set of ground-based and airborne electromagnetic ice thickness measurements collected between 2001 and 2012 is presented here, including long transects well into the southern part of the Transpolar Drift obtained using fixed-wing aircrafts. The source area for the surveyed ice is primarily the Laptev Sea, and the estimated age is consistent with a decreased from 3 to 2 years between 1990 and 2012. The data consistently also show a general thinning for the last decade, with a decrease in modal thickness of second year and multiyear ice, and a decrease in mean thickness and fraction of ice thicker than 3 m. Local melting in the strait was investigated in two surveys performed in the downstream direction, showing a decrease of 0.19 m degree−1 latitude south of 81° N probably driven by bottom melting from warm water of Atlantic origin. Further north variability in ice thickness is more related to differences in age and deformation. The thickness observations were combined with ice area export estimates to calculate summer volume fluxes of sea ice. This shows that it is possible to determine volume fluxes through Fram Strait during summer when satellite based sea ice thickness information is missing. While the ice area export based on satellite remote sensing shows positive trends since 2001, the mean fluxes during summer (July and August are small (18 km3, and long-term trends are uncertain due to the limited surveys available.

  7. Potential Polyunsaturated Aldehydes in the Strait of Gibraltar under Two Tidal Regimes

    Directory of Open Access Journals (Sweden)

    Soledad Morillo-García

    2014-03-01

    Full Text Available Diatoms, a major component of the large-sized phytoplankton, are able to produce and release polyunsaturated aldehydes after cell disruption (potential PUAs or pPUA. These organisms are dominant in the large phytoplankton fraction (>10 µm in the Strait of Gibraltar, the only connection between the Mediterranean Sea and the Atlantic Ocean. In this area, the hydrodynamics exerts a strong control on the composition and physiological state of the phytoplankton. This environment offers a great opportunity to analyze and compare the little known distribution of larger sized PUA producers in nature and, moreover, to study how environmental variables could affect the ranges and potential distribution of these compounds. Our results showed that, at both tidal regimes studied (Spring and Neap tides, diatoms in the Strait of Gibraltar are able to produce three aldehydes: Heptadienal, Octadienal and Decadienal, with a significant dominance of Decadienal production. The PUA released by mechanical cell disruption of large-sized collected cells (pPUA ranged from 0.01 to 12.3 pmol from cells in 1 L, and from 0.1 to 9.8 fmol cell−1. Tidal regime affected the abundance, distribution and the level of physiological stress of diatoms in the Strait. During Spring tides, diatoms were more abundant, usually grouped nearer the coastal basin and showed less physiological stress than during Neap tides. Our results suggest a significant general increase in the pPUA productivity with increasing physiological stress for the cell also significantly associated to low nitrate availability.

  8. Reconstruction of transports through the Strait of Gibraltar from limited observations

    Science.gov (United States)

    Jordà, G.; Sánchez-Román, A.; Gomis, D.

    2016-04-01

    Observing the water transports through the Strait of Gibraltar is a difficult task. Here we present a methodology aimed to obtain the inflow, outflow and net transport of water from the limited set of available observations, currently consisting of an upward looking ADCP deployed at Espartel sill, two tide gauges located at each side of the Strait and radars monitoring the surface velocities. More precisely, we reconstruct the velocity field over a vertical section across the Strait using a reduced order optimal interpolation technique fed with the spatial covariance patterns deduced from high resolution numerical simulations. As a first step we carry out some sensitivity experiments with synthetic data that demonstrate the high potential of the approach. The reconstruction methodology can reproduce very satisfactorily the variability of the transports with estimated correlations for the inflow, outflow and net over 0.9 in all the cases and estimated RMS errors of 0.03, 0.08 and 0.05 Sv, respectively. However, we have also found that the reconstruction is sensible to bias problems, mostly due to the sensitivity of the method to the differences between the statistics of the actual and modeled velocity profiles. The sensitivity experiments have been used to tune the parameters of the method and a reconstruction of actual monthly transports has been performed for the period 2004-2010 along with an estimate of the associated uncertainty. This reconstruction provides for the first time a multiannual time series of the inflow and the net transports solely based on in situ observations. Therefore it can be used as an independent estimate for the validation of numerical models and surface freshwater fluxes in the Mediterranean.

  9. Acoustic imaging of the Mediterranean water outflowing through the Strait of Gibraltar

    Science.gov (United States)

    Biescas Gorriz, Berta; Carniel, Sandro; Sallarès, Valentí; Rodriguez Ranero, Cesar

    2016-04-01

    Acoustic imaging of the Mediterranean water outflowing through the Strait of Gibraltar Berta Biescas (1), Sandro Carniel (2) , Valentí Sallarès (3) and Cesar R. Ranero(3) (1) Istituto di Scienze Marine, CNR, Bologna, Italy (2) Istituto di Scienze Marine, CNR, Venice, Italy (3) Institut de Ciències del Mar, CSIC, Barcelona, Spain Acoustic reflectivity acquired with multichannel seismic reflection (MCS) systems allow to detect and explore the thermohaline structure in the ocean with vertical and lateral resolutions in the order of 10 m, covering hundreds of kilometers in the lateral dimension and the full-depth water column. In this work we present a MCS 2D profile that crosses the Strait of Gibraltar, from the Alboran Sea to the internal Gulf of Cadiz (NE Atlantic Ocean). The MCS data was acquired during the Topomed-Gassis Cruise (European Science Foundation TopoEurope), which was carried out on board of the Spanish R/V Sarmiento de Gamboa in October 2011. The strong thermohaline contrast between the Mediterranean water and the Atlantic water, characterizes this area and allows to visualize, with unprecedented resolution, the acoustic reflectivity associated to the dense flow of the Mediterranean water outflowing through the prominent slope of the Strait of Gibraltar. During the first kilometers, the dense flow drops attached to the continental slope until it reaches the buoyancy depth at 700 m. Then, it detaches from the sea floor and continues flowing towards the Atlantic Ocean, occupying the layer at 700-1500 m deep and developing clear staircase layers. The reflectivity images display near seabed reflections that could well correspond to turbidity layers. The XBT data acquired coincident in time and space with the MCS data will help us in the interpretation and analysis of the acoustic data.

  10. Performance Evaluation of HYCOM-GOM for Hydrokinetic Resource Assessment in the Florida Strait

    Energy Technology Data Exchange (ETDEWEB)

    Neary, Vincent S [ORNL; Gunawan, Budi [ORNL; Ryou, Albert S [ORNL

    2012-06-01

    The U.S. Department of Energy (DoE) is assessing and mapping the potential off-shore ocean current hydrokinetic energy resources along the U.S. coastline, excluding tidal currents, to facilitate market penetration of water power technologies. This resource assessment includes information on the temporal and three-dimensional spatial distribution of the daily averaged power density, and the overall theoretical hydrokinetic energy production, based on modeled historical simulations spanning a 7-year period of record using HYCOM-GOM, an ocean current observation assimilation model that generates a spatially distributed three-dimensional representation of daily averaged horizontal current magnitude and direction time series from which power density time series and their statistics can be derived. This study ascertains the deviation of HYCOM-GOM outputs, including transport (flow) and power density, from outputs based on three independent observation sources to evaluate HYCOM-GOM performance. The three independent data sources include NOAA s submarine cable data of transport, ADCP data at a high power density location, and HF radar data in the high power density region of the Florida Strait. Comparisons with these three independent observation sets indicate discrepancies with HYCOM model outputs, but overall indicate that the HYCOM-GOM model can provide an adequate assessment of the ocean current hydrokinetic resource in high power density regions like the Florida Strait. Additional independent observational data, in particular stationary ADCP measurements, would be useful for expanding this model performance evaluation study. ADCP measurements are rare in ocean environments not influenced by tides, and limited to one location in the Florida Strait. HF radar data, although providing great spatial coverage, is limited to surface currents only.

  11. Population ecology of polar bears in Davis Strait, Canada and Greenland

    Science.gov (United States)

    Peacock, Elizabeth; Taylor, Mitchell K.; Laake, Jeffrey L.; Stirling, Ian

    2013-01-01

    Until recently, the sea ice habitat of polar bears was understood to be variable, but environmental variability was considered to be cyclic or random, rather than progressive. Harvested populations were believed to be at levels where density effects were considered not significant. However, because we now understand that polar bear demography can also be influenced by progressive change in the environment, and some populations have increased to greater densities than historically lower numbers, a broader suite of factors should be considered in demographic studies and management. We analyzed 35 years of capture and harvest data from the polar bear (Ursus maritimus) subpopulation in Davis Strait, including data from a new study (2005–2007), to quantify its current demography. We estimated the population size in 2007 to be 2,158 ± 180 (SE), a likely increase from the 1970s. We detected variation in survival, reproductive rates, and age-structure of polar bears from geographic sub-regions. Survival and reproduction of bears in southern Davis Strait was greater than in the north and tied to a concurrent dramatic increase in breeding harp seals (Pagophilus groenlandicus) in Labrador. The most supported survival models contained geographic and temporal variables. Harp seal abundance was significantly related to polar bear survival. Our estimates of declining harvest recovery rate, and increasing total survival, suggest that the rate of harvest declined over time. Low recruitment rates, average adult survival rates, and high population density, in an environment of high prey density, but deteriorating and variable ice conditions, currently characterize the Davis Strait polar bears. Low reproductive rates may reflect negative effects of greater densities or worsening ice conditions.

  12. Delivery of eye and vision services in Aboriginal and Torres Strait Islander primary health care centres

    Directory of Open Access Journals (Sweden)

    Anthea M Burnett

    2016-12-01

    Full Text Available Background: Routine eye and vision assessments are vital for the detection and subsequent management of vision loss, which is particularly important for Aboriginal and Torres Strait Islander people, who face higher rates of vision loss than other Australians. In order to guide improvements, this paper will describe patterns, variations and gaps in these eye and vision assessments for Aboriginal and Torres Strait Islander people. Methods: Clinical audits from 124 primary health care centres (sample size 15,175 from five Australian States and Territories were conducted during 2005-2012. Main outcome measure was adherence to current guidelines for delivery of eye and vision assessments to adults with diabetes, those without a diagnosed major chronic disease and children attending primary health care centres. Results: Overall delivery of recommended eye and vision assessments varied widely between health centres. Of the adults with diabetes, 45% had a visual acuity assessment recorded within the previous 12 months (health centre range 0-88%, and 33% had a retinal examination recorded (health centre range 0-73%. Of the adults with no diagnosed major chronic disease, 31% had a visual acuity assessment recorded within the previous two years (health centre range 0-30%, and 13% had received an examination for trichiasis (health centre range 0-40%. In children, 49% had a record of a vision assessment (health centre range 0-97%, and 25% had a record of an examination for trachoma within the previous 12 months (health centre range 0-63%. Conclusions: There was considerable range, and variation in the recorded delivery of scheduled eye and vision assessments across health centres. Sharing the successful strategies of the better-performing health centres to support focused improvements in key areas of need may increase overall rates of eye examinations – important for the timely detection, referral and treatment of eye conditions affecting Aboriginal and

  13. Application of chemometric studies to metal concentrations in molluscs from the Strait of Magellan (Chile).

    Science.gov (United States)

    España, M S Astorga; Rodríguez, E M Rodríguez; Romero, C Díaz

    2007-05-01

    Na, K, Ca, Mg, Fe, Cu, Zn, Mn, Se, Ni, and Cd concentrations were determined in 126 mollusc samples belonging to five different species (Mytilus chilensis, n = 47; Nacella deaurata, n = 65; Aulacomya ater, n = 4; Fissurella picta, n = 4; Acanthina monodon, n = 6) collected from the coasts of the Strait of Magellan. The metals analysed presented significant differences between the mean concentrations for the mollusc species considered. Factor and discriminant analyses made possible the differentiation of the mollusc species. In addition, when discriminant analysis was used, good classifications were obtained according to sampling zone and weight-to-length ratio of the organisms.

  14. On the Mechanisms of Episodic Salinity Outflow Events in the Strait of Hormuz

    Science.gov (United States)

    2008-12-18

    ronmental Model (GDEM3) seasonally varying clima - tology with an {’-folding time scale of 1-76 days. The monthly river inflow into the basin is...noted that in all simulations sea sur- face salinity is restored to the GDEM3 monthly clima - tology with a time scale of ~30 days. As a result, the...strait at the southern part of the channel joins the inflow from the Gulf of Oman. The eastern extent of this returning flow shows high temporal vari

  15. Water mass distribution in Fram Strait and over the Yermak Plateau in summer 1997

    Directory of Open Access Journals (Sweden)

    B. Rudels

    Full Text Available The water mass distribution in northern Fram Strait and over the Yermak Plateau in summer 1997 is described using CTD data from two cruises in the area. The West Spitsbergen Current was found to split, one part recirculated towards the west, while the other part, on entering the Arctic Ocean separated into two branches. The main inflow of Atlantic Water followed the Svalbard continental slope eastward, while a second, narrower, branch stayed west and north of the Yermak Plateau. The water column above the southeastern flank of the Yermak Plateau was distinctly colder and less saline than the two inflow branches. Immediately west of the outer inflow branch comparatively high temperatures in the Atlantic Layer suggested that a part of the extraordinarily warm Atlantic Water, observed in the boundary current in the Eurasian Basin in the early 1990s, was now returning, within the Eurasian Basin, toward Fram Strait. The upper layer west of the Yermak Plateau was cold, deep and comparably saline, similar to what has recently been observed in the interior Eurasian Basin. Closer to the Greenland continental slope the salinity of the upper layer became much lower, and the temperature maximum of the Atlantic Layer was occasionally below 
    0.5 °C, indicating water masses mainly derived from the Canadian Basin. This implies that the warm pulse of Atlantic Water had not yet made a complete circuit around the Arctic Ocean. The Atlantic Water of the West Spitsbergen Current recirculating within the strait did not extend as far towards Greenland as in the 1980s, leaving a broader passage for waters from the Atlantic and intermediate layers, exiting the Arctic Ocean. A possible interpretation is that the circulation pattern alternates between a strong recirculation of the West Spitsbergen Current in the strait, and a larger exchange of Atlantic Water between the Nordic Seas and the inner parts of the Arctic Ocean.

    Key words: Oceanography: general

  16. Gibraltar Experiment: A Plan for Dynamic and Kinematic Investigations of Strait Mixing, Exchange and Turbulence

    Science.gov (United States)

    1985-08-01

    Garcia, M2 J. Garcia Objetivos . - 1) Anfilisis armo’nico de mareas registradas en Ceuta, Tarifa, Tra- falgar y Pta. Carnero, 2). Correlaci 6 n entre...pr-ograma ha sido financiado por SECEG. L -~ f. o; soP j!", 58 M~AREAS EN GIBRALTAR Jos6 W~ Garcia Mor-6n, Jos6 L. L6pez Objetivos . - A) Estudio de...Gibraltar Strait. HIDROGRAFIA Gregoria Parrilla, Rafael Molina 6 Objetivos . - Las medidas hechas con el CTD servir n para los siguientes obje- tivos

  17. Sensitivity of the Denmark Strait Overflow to various parameterizations in a z-coordinate numerical model

    Science.gov (United States)

    Colombo, Pedro; Barnier, Bernard; Penduff, Thierry; Molines, Jean-Marc

    2016-04-01

    Overflows play a key role in the climate system by ventilating deep waters, feeding boundary currents and determining the stratification of the deep ocean. Their correct representation is still an open issue in geopotential-coordinate global ocean models, and leads to misrepresentations of deep and bottom water masses. In this work we quantify the sensitivity of a realistic Denmark Strait regional configuration of the NEMO OGCM at 1/12° horizontal resolution to various parameters: partial vs full cells, use of a bottom boundary layer parameterization, and vertical resolution. We also provide a quantification of the spurious dyapicnal mixing present in the overflow through a passive tracer online release experiment.

  18. Transient tracer distributions in the Fram Strait in 2012 and inferred anthropogenic carbon content and transport

    Science.gov (United States)

    Stöven, Tim; Tanhua, Toste; Hoppema, Mario; von Appen, Wilken-Jon

    2016-02-01

    The storage of anthropogenic carbon in the ocean's interior is an important process which modulates the increasing carbon dioxide concentrations in the atmosphere. The polar regions are expected to be net sinks for anthropogenic carbon. Transport estimates of dissolved inorganic carbon and the anthropogenic offset can thus provide information about the magnitude of the corresponding storage processes. Here we present a transient tracer, dissolved inorganic carbon (DIC) and total alkalinity (TA) data set along 78°50' N sampled in the Fram Strait in 2012. A theory on tracer relationships is introduced, which allows for an application of the inverse-Gaussian-transit-time distribution (IG-TTD) at high latitudes and the estimation of anthropogenic carbon concentrations. Mean current velocity measurements along the same section from 2002-2010 were used to estimate the net flux of DIC and anthropogenic carbon by the boundary currents above 840 m through the Fram Strait. The new theory explains the differences between the theoretical (IG-TTD-based) tracer age relationship and the specific tracer age relationship of the field data, by saturation effects during water mass formation and/or the deliberate release experiment of SF6 in the Greenland Sea in 1996, rather than by different mixing or ventilation processes. Based on this assumption, a maximum SF6 excess of 0.5-0.8 fmol kg-1 was determined in the Fram Strait at intermediate depths (500-1600 m). The anthropogenic carbon concentrations are 50-55 µmol kg-1 in the Atlantic Water/Recirculating Atlantic Water, 40-45 µmol kg-1 in the Polar Surface Water/warm Polar Surface Water and between 10 and 35 µmol kg-1 in the deeper water layers, with lowest concentrations in the bottom layer. The net fluxes through the Fram Strait indicate a net outflow of ˜ 0.4 DIC and ˜ 0.01 PgC yr-1 anthropogenic carbon from the Arctic Ocean into the North Atlantic, albeit with high uncertainties.

  19. A Fram Strait Experiment: Sensing Sea Ice Conditions using Shipborne GNSS Reflectometry

    Science.gov (United States)

    Semmling, Maximilian; Rösel, Anja; Ludwig, Marcel; Bratrein, Marius; Gerland, Sebastian; Wickert, Jens

    2017-04-01

    Cruises of the Norwegian research vessel (R/V) Lance provide regular in-situ measurements of ocean and sea ice properties in Fram Strait, at the major link between the Arctic and the Atlantic Ocean. A GNSS reflectometry (GNSS-R) setup has been installed aboard R/V Lance to investigate sea ice remote sensing opportunities during the Fram Strait 2016 cruise. The experiment is based on previous coastal investigations, which demonstrated the ocean altimetric potential of GNSS-R and its sensitivity to the sea ice cover. The presence of sea ice can be detected by the reduced sea surface roughness that affects the coherence of the GNSS-R carrier phase. Differential phase observations of the reflected signal relative to the direct signal are considered here. The objective of this study is the retrieval of the coherent differential phase resolving the altimetric effect of changes in the sea ice thickness. Grazing reflections with satellite elevations GNSS signals introduces significant biases in the differential phase especially at grazing elevations. The shipborne setup with antenna heights of 24 m above sea level allows to study grazing reflections disregarding the atmospheric bias. The setup slightly differs from common shipborne GNSS equipment. It consists of a GORS (GNSS Occultation Reflectometry Scatterometry) receiver, based on commercial JAVAD hardware. Two antenna links are starbord-looking with right- and left-handed circular polarization to detect the reflected signal. One right-handed antenna is up-looking for reference to the direct signal. In-phase and quadrature (I,Q) samples from the three antenna links were recorded during the entire Fram Strait cruise, between 25 August and 13 September 2016. The ship's track on its main section went from Svalbard at 10° E roughly along 79° N to the Eastern Greenland coast at 13° W and back. Different ice conditions were encountered: open water with a rough sea surface close to Svalbard, a dense coverage of multiyear

  20. Composition of phytoplankton in the Bransfield Strait and Elephant Island during austral summer of 1999

    Directory of Open Access Journals (Sweden)

    Sonia Sánchez

    2014-06-01

    Full Text Available The authors inform about the composition and distribution of phytoplanktonic community between the first 75 m of depth in Bransfield Strait y around the Elephant island, during the ANTAR X expedition in the 1999 Austral Summer (22nd–29th January 1999. The higher cellular concentration (500 cel/mL was given by the autotrophic nanoplankton, with a high density mainly on the bay stations and down the first 25 m of depth. Among the most representative species we have Leucocryptos marina, Phaeocystis antarctica, the Monadas and the pennate diatoms.

  1. On the origin and propagation of Denmark Strait Overflow Water Anomalies in the Irminger Basin

    Science.gov (United States)

    Jochumsen, Kerstin; Quadfasel, Detlef; Köllner, Manuela; Dye, Stephen; Rudels, Bert; Valdimarsson, Hedinn

    2015-04-01

    Denmark Strait Overflow Water (DSOW) supplies the densest contribution to North Atlantic Deep Water and is monitored at several locations in the subpolar North Atlantic. We present an analysis of observed hydrographic (temperature and salinity) and velocity time series from three multiple-mooring arrays to quantify the variability and to track anomalies of DSOW: (1) at the Denmark Strait sill, (2) at 180 km downstream (south of Dohrn Bank) and (3) at a further 320 km downstream on the east Greenland continental slope near Tasiilaq (formerly Angmagssalik). The aim of the combined arrays is to cover the overflow plume and its modifications due to its descent and mixing with ambient waters from the sill of Denmark Strait to approx. 2000 m depth in the northern Irminger Basin. Eddy variability dominates the high frequency variations in all DSOW records. Variability on time scales from interannual to weekly is present at all moorings, but no long term trends are detected in the time series. The seasonal cycle is of no importance for the properties measured at the sill, but its significance increases with downstream distance. A low pass filter (cut-off at 20 days) is applied to the time series in order to remove synoptic scale variations: single eddies are likely not traceable and probably merge with each other or fade along the descending pathway of the DSOW plume. The hydrographic time series from different moorings within each mooring array show coherent signals, while the velocity fluctuations are only weakly correlated. Lagged correlations of anomalies between the arrays reveal propagation from the sill of Denmark Strait to the Angmagssalik array in potential temperature with an average propagation time of 16 days. Despite a difference of 1.5°C between the mean temperatures at both arrays, which are about 500 km away from each other, temperature anomalies can be traced along the DSOW pathway. In contrast, the correlations in salinity are low and only significant

  2. High risk alcohol-related trauma among the Aboriginal and Torres Strait Islanders in the Northern Territory.

    Science.gov (United States)

    Jayaraj, Rama; Thomas, Mahiban; Thomson, Valerie; Griffin, Carolyn; Mayo, Luke; Whitty, Megan; d'Abbs, Peter; Nagel, Tricia

    2012-08-03

    High risk drinking is linked with high rates of physical harm. The reported incidence of alcohol - related trauma among Aboriginal and Torres Strait Islander people in the Northern Territory is the highest in the world. Facial fractures are common among young Aboriginal and Torres Strait Islanders. They are often linked with misuse of alcohol in the Northern Territory and are frequently secondary to assault. This review focuses on alcohol-related trauma in the Territory and draws attention to an urgent need for preventative health approach to address this critical issue.

  3. On the variability of Florida Straits and wind driven transports at 26° N in the Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    T. Kanzow

    2010-04-01

    Full Text Available Since April 2004 the RAPID array has made continuous measurements of the Atlantic Meridional Overturning Circulation (AMOC at 26° N. Two key components of this system are Ekman transport zonally integrated across 26° N and western boundary current transport in the Florida Straits. Whilst measurements of the AMOC as a whole are somewhat in their infancy, this study investigates what useful information can be extracted on the variability of the Ekman and Florida Straits transports using the decadal timeseries already available. Analysis is also presented for Sverdrup transports zonally integrated across 26° N. The seasonal cycles of Florida Straits, Ekman and Sverdrup transports are quantified at 26° N using harmonic analysis of annual and semi-annual constituents. Whilst Sverdrup transport shows clear semi-annual periodicity, calculations of seasonal Florida Straits and Ekman transports show substantial interannual variability due to variability at non-seasonal frequencies; the mean seasonal cycle for these transports only emerges from decadal length observations. The Florida Straits and Ekman mean seasonal cycles project on the AMOC with a combined peak-to-peak seasonal range of 3.5 Sv. The combined seasonal range for heat transport is 0.40 PW. The Florida Straits seasonal cycle possesses a smooth annual periodicity in contrast with previous studies suggesting a more asymmetric structure. No clear evidence is found to support significant changes in the Florida Straits seasonal cycle at sub-decadal periods. Whilst evidence of wind driven Florida Straits transport variability is seen at sub-seasonal and annual periods, model runs from the 1/4° eddy-permitting ocean model NEMO are used to identify an important contribution from internal oceanic variability at sub-annual and interannual periods. The Ekman transport seasonal cycle possesses less symmetric structure, due in part to different seasonal transport regimes east and west of 50 to 60

  4. Coastal Erosion Along the West Coast of the Taiwan Strait and It's Influencing Factors

    Institute of Scientific and Technical Information of China (English)

    LIU Jianhui; CAI Feng; QI Hongshuai; LEI Gang; CAO Lihua

    2011-01-01

    Based on the field surveys and repeated cross-profile observations combined with the comparison of many years' topographic maps, this study shows the spatial variability and varying patterns of coastal erosion along the west coast of the Taiwan Strait. Regional differentiation in the Meso-Cenozoic coastal tectonics determined the irregular coastline and geological background for large-scale coastal erosion distribution. The intensity of coastal erosion on the west side of the Taiwan Strait is mild in the northern region, severe in the central region and modest in the southern region. The beaches along the coast are mainly backed by dunes, seawalls or cliffs. The dunes and beaches show periodic erosion and recovery along the coast adjacent to river mouths, while persistent retreat of frontal dunes and beaches tends to occur in other areas. The beach erosion occurs mainly in front of seawalls. Due to the low strength of the unconsolidated sediment the soft cliffs suffer the severest coastline recession. Sea level rise and river sediment discharge reduction are main causes of coastal erosion. Storm surge is common in the studied area and plays an important role in the progress of coastal erosion. Human activities including coastal constructions and sand mining also tend to interfere strongly with the balance of sediment budget in some coastal cells.

  5. Small-scale variability of the current in the Strait of Bonifacio

    Science.gov (United States)

    Gérigny, Olivia; Coudray, Sylvain; Lapucci, Chiara; Tomasino, Corinne; Bisgambiglia, Paul-Antoine; Galgani, François

    2015-08-01

    Current dynamics in the Strait of Bonifacio (south Corsica) were investigated at a small scale during the STELLAMARE1 multidisciplinary cruise in summer 2012, using in situ measurements and modeling data. The Strait of Bonifacio is a particularly sensitive marine area in which specific conservation measures have been taken to preserve the natural environment and wild species. Good knowledge of the hydrodynamics in this area is essential to optimize the Marine Protected Area's management rules. Therefore, we used a high-resolution model (400 m) based on the MARS3D code to investigate the main flux exchanges and to formulate certain hypotheses about the formation of possible eddy structures. The aim of the present paper is first to synthetize the results obtained by combining Acoustic Doppler Current Profiler data, hydrological parameters, Lagrangian drifter data, and satellite observations such as MODIS OC5 chlorophyll a data or Metop-A AVHRR Sea Surface Temperature (SST) data. These elements are then used to validate the presence of the mesoscale eddies simulated by the model and their recurrence outside the cruise period. To complete the analysis, the response of the 3D hydrodynamical model was evaluated under two opposing wind systems and certain biases were detected. Strong velocities up to 1 m s-1 were recorded in the east part due to the Venturi effect; a complementary system of vortices governed by Coriolis effect and west wind was observed in the west part, and horizontal stratification in the central part has been identified under typical wind condition.

  6. Recent observations of seasonal variability of the Mediterranean outflow in the Strait of Gibraltar

    Science.gov (United States)

    GarcíA Lafuente, J.; SáNchez RomáN, A.; DíAz Del RíO, G.; Sannino, G.; SáNchez Garrido, J. C.

    2007-10-01

    Recent observations of the outflowing Mediterranean water collected near the bottom in key points of the Strait of Gibraltar show the existence of a seasonal cycle with warmer and lighter waters leaving the Mediterranean Sea in winter and cooler and denser waters in spring early summer. The amplitude of the signal is around 5 10-2 °C for potential temperature and 1.5 10-2 for potential density, salinity hardly showing seasonal fluctuations. The outflow also shows a seasonal cycle with maximum volume transport in April, in coincidence with the minimum of the signal of potential temperature. A simple analysis of the composition of the outflow in terms of the main water masses of the western Mediterranean basin and its comparison with climate indicators suggests that the seasonal cycle follows the annual process of the Western Mediterranean Deep Water formation that replenish the deep portion of the basin by the end of winter and rises the level of the deep water reservoir, facilitating the suction of cooler and denser water from the Mediterranean over the sills of the Strait. From this time onwards, the data show a smooth warming that would be explained by the progressive fall of the level of the Western Mediterranean Deep Water as it is drained out the Mediterranean, which would leave warmer water available for suction. The process is asymmetric in the sense that the transition from high to low temperature is completed in a short period while the progressive warming spans a longer period.

  7. Assessment of pollution aerosols sources above the Straits of Dover using lead isotope geochemistry.

    Science.gov (United States)

    Deboudt, K; Flament, P; Weis, D; Mennessier, J P; Maquinghen, P

    1999-09-15

    We assess the capability of lead isotopes to study the transport of pollution aerosols above the Straits of Dover by collecting atmospheric aerosols above the Eastern Channel and the Southern Bight of the North Sea. During the same period, we characterized the lead isotopic signature of the main industrial sources on the French coast near the Straits of Dover. Urban and automobile-derived aerosols were also collected. Due to the phasing out of lead in gasoline, the urban isotopic composition (206Pb/207Pb = 1.158 +/- 0.003) has become more radiogenic, although it is highly variable. On a regional scale, major industrial emissions have a well-defined isotopic composition (1.13 isotopic compositions, it can be shown that lead aerosols originating from eastern Europe have an isotopic signature (1.145 isotopic composition of west-European lead aerosols (1.111 < 206Pb/207Pb < 1.142). The influence of remote North American sources is suggested, with caution, due to uncertainties in meteorological calculations.

  8. Sound speed as a proxy variable to temperature in Fram Strait.

    Science.gov (United States)

    Dushaw, Brian D; Sagen, Hanne; Beszczynska-Möller, Agnieszka

    2016-07-01

    The application of ocean acoustic tomography in Fram Strait requires a careful assessment of the accuracy to which estimates of sound speed from tomography can be converted to estimates of temperature. The Fram Strait environment is turbulent, with warm, salty, northward-flowing North Atlantic water interacting with cold, fresh, southward-flowing Arctic water. The nature of this environment suggests that salinity could play an important role with respect to sound speed. The properties of sound speed with respect to temperature and salinity in this environment were examined using climatological and in situ glider data. In cold water, a factor of about 4.5 m s(-1) °C(-1) can be used to scale between sound speed and temperature. In situ data obtained by gliders were used to determine the ambiguities between temperature, salinity, and sound speed. Tomography provides a depth-averaging measurement. While errors in the sound speed-temperature conversion at particular depths may be 0.2 °C or larger, particularly within 50 m of the surface, such errors are suppressed when the depth is averaged. Using a simple scale factor to compute temperature from sound speed introduced an error of about 20 m °C for depth-averaged temperature, a value less than formal uncertainties estimated from acoustic tomography.

  9. Surface circulation at the Strait of Gibraltar: A combined HF radar and high resolution model study

    Science.gov (United States)

    Soto-Navarro, Javier; Lorente, Pablo; Álvarez Fanjul, Enrique; Carlos Sánchez-Garrido, Jose; García-Lafuente, Jesús

    2016-03-01

    Observations from a high frequency radar system and outputs from a high resolution operational ocean model working at the Strait of Gibraltar have been analyzed and compared during the period February 2013 to September 2014 in order to evaluate their capability to resolve the surface circulation of the region. The description of the mean circulation patterns has been statistically assessed, showing good agreement, particularly in the central region of the strait corresponding with the Atlantic Jet (AJ) stream, although some short scale features are not reproduced by the model. In the frequency domain very high concordance is observed. Tidal maps of diurnal and semidiurnal constituents are in good agreement with previous observations. The analysis of the model and radar response to the wind forcing reveals that the low resolution of the model wind-forcing field and its deeper superficial level smoothes the wind effect on the simulated currents. The first three EOF modes account for the 86% of model and radar variances. The coincidence between the observed and simulated patterns is very significant for the first two modes, which account for the mean velocity field and the latitudinal shifting of the AJ consequence of the flow-topography interaction. The third mode captures the wind-induced circulation, and greater discrepancies are found in this case. Results underline the complementary character of both systems: radar observations improve the model description, resolving short scale processes, while the model completes the radar information when the time or spatial coverage is poorer.

  10. Mesoscale mixing of the Denmark Strait Overflow in the Irminger Basin

    Science.gov (United States)

    Koszalka, Inga M.; Haine, Thomas W. N.; Magaldi, Marcello G.

    2017-04-01

    The Denmark Strait Overflow (DSO) is a major export route for dense waters from the Nordic Seas forming the lower limb of the Atlantic Meridional Overturning Circulation, an important element of the climate system. Mixing processes along the DSO pathway influence its volume transport and properties contributing to the variability of the deep overturning circulation. They are poorly sampled by observations, however, which hinders development of a proper DSO representation in global circulation models. We employ a high resolution regional ocean model of the Irminger Basin to quantify impact of the mesoscale flows on DSO mixing focusing on geographical localization and the time-modulation of water property changes. The model reproduces the observed bulk warming of the DSO plume 100-200 km downstream of the Denmark Strait sill. It also reveals that mesoscale variability of the overflow ('DSO-eddies', of 20-30 km extent and a time scale of 2-5 day) modulates water property changes and turbulent mixing, diagnosed with the vertical shear of horizontal velocity and the eddy heat flux divergence. The space-time localization of the DSO mixing and warming and the role of coherent mesoscale structures should be explored by turbulence measurements and factored into the coarse circulation models.

  11. Tsunamigenic potential of a newly discovered active fault zone in the outer Messina Strait, Southern Italy

    Science.gov (United States)

    Fu, Lili; Heidarzadeh, Mohammad; Cukur, Deniz; Chiocci, Francesco L.; Ridente, Domenico; Gross, Felix; Bialas, Jörg; Krastel, Sebastian

    2017-03-01

    The 1908 Messina tsunami was the most catastrophic tsunami hitting the coastline of Southern Italy in the younger past. The source of this tsunami, however, is still heavily debated, and both rupture along a fault and a slope failure have been postulated as potential origin of the tsunami. Here we report a newly discovered active Fiumefreddo-Melito di Porto Salvo Fault Zone (F-MPS_FZ), which is located in the outer Messina Strait in a proposed landslide source area of the 1908 Messina tsunami. Tsunami modeling showed that this fault zone would produce devastating tsunamis by assuming slip amounts of ≥5 m. An assumed slip of up to 17 m could even generate a tsunami comparable to the 1908 Messina tsunami, but we do not consider the F-MPS_FZ as a source for the 1908 Messina tsunami because its E-W strike contradicts seismological observations of the 1908 Messina earthquake. Future researches on the F-MPS_FZ, however, may contribute to the tsunami risk assessment in the Messina Strait.

  12. Filament generation off the Strait of Gibraltar in response to Gap winds

    Science.gov (United States)

    Peliz, Álvaro; Teles-Machado, Ana; Marchesiello, Patrick; Dubert, Jesus; Lafuente, Jesus Garcia

    2009-01-01

    We present a case study of the generation of a cold filament rooted off the southwestern edge of the Strait of Gibraltar (Atlantic side) during the summer of 2000. The event is successfully simulated using high-resolution atmospheric and oceanic numerical models. It is shown that a sharp filament may develop oceanwards with little modification of the Atlantic inflow into the Mediterranean, contrary to usual expectations. The filament is essentially driven by the surface layer response to Gap winds occurring during Levanter conditions. The easterly wind funnelling in the Strait generates a strong wind jet and intense wind curl which impacts the oceanic surface layer through Ekman pumping and mixing processes. The generation and fate of the filament is very similar to the Gulf of Tehuantepec case, where strong Gap wind events produce asymmetric deformation and erosion of the thermocline that tends to favour anticyclonic mesoscale circulations. Our observations and model results from both realistic and idealized experiments suggest that similar phenomena are present in the Gulf of Cadiz, but they are altered by the persisting Atlantic inflow, so that the response to Gap winds is not as dramatic.

  13. Trace metals in surface sediments of the Taiwan Strait: geochemical characteristics and environmental indication.

    Science.gov (United States)

    Gao, Xuelu; Zhou, Fengxia; Lui, Hon-Kit; Lou, Jiann-Yuh; Chen, Chen-Tung Arthur; Zhuang, Wen

    2016-06-01

    The concentration and geochemical fractionation of six trace metals related with environmental quality assessment, namely Cd, Cr, Cu, Ni, Pb, and Zn, in 30 surface sediments from both inshore and offshore areas of the Taiwan Strait were measured to investigate their distribution characteristics, evaluate their potential mobility, and assess their pollution status. The geoaccumulation index results indicated that, on average, the studied metals presented an order of Cd > Pb > Ni > Zn > Cu > Cr and were practically in uncontaminated status except Cd. The results of the sequential extraction analysis indicated that, on average, the studied metals were mostly accumulated in residual fraction except Cd whose concentration was the highest in the acid soluble fraction presenting a high risk to the environment, and their mobility decreased in the sequence of Cd > Pb > Ni > Cu > Zn > Cr. Based on the mean probable effect level quotients, the combination of the studied metals had an 8 % probability of being toxic at two sampling sites and had a 21 % probability of being toxic at the rest of sites. The spatial distribution of the studied metals in total concentrations and different geochemical fractions corroborated the previous findings about the possible sediment transportation routes in and around the Taiwan Strait.

  14. PM10 retrieval over the water surface of Penang Straits from Landsat TM5 data

    Science.gov (United States)

    Lim, H. S.; MatJafri, M. Z.; Abdullah, K.; Saleh, N. Mohd.; Hashim, S. A.

    2007-04-01

    In this study, we used the Landsat TM data captured on 9 March 2006 for the retrieval of PM10 over the water surface of Penang Straits, Malaysia. PM10 measurements were collected using a handheld DustTrak TM meter simultaneously with the remotely sensed data acquisition. The PCI Geomatica version 9.1 digital image processing software was used in all image-processing analysis. An algorithm was developed based on the atmospheric optical characteristic. The digital numbers were extracted corresponding to the ground-truth locations for each band and then converted into radiance and reflectance values. The reflectance measured from the satellite [reflectance at the top of atmospheric, ρ(TOA)] was subtracted by the amount given by the surface reflectance to obtain the atmospheric reflectance. Then the atmospheric reflectance was related to the PM10 using regression analysis. These atmospheric reflectance values were used for calibration of the PM10 algorithm. The developed algorithm was used to correlate the digital signal and the PM10 concentration. The proposed algorithm produced a high correlation coefficient (R) and low root-mean-square error (RMS). The PM10 concentration was generated using this algorithm over the water surface of Penang straits.

  15. Linkages between atmospheric blocking, sea ice export through Fram Strait and the Atlantic Meridional Overturning Circulation

    Science.gov (United States)

    Ionita, M.; Scholz, P.; Lohmann, G.; Dima, M.; Prange, M.

    2016-09-01

    As a key persistent component of the atmospheric dynamics, the North Atlantic blocking activity has been linked to extreme climatic phenomena in the European sector. It has also been linked to Atlantic multidecadal ocean variability, but its potential links to rapid oceanic changes have not been investigated. Using a global ocean-sea ice model forced with atmospheric reanalysis data, here it is shown that the 1962–1966 period of enhanced blocking activity over Greenland resulted in anomalous sea ice accumulation in the Arctic and ended with a sea ice flush from the Arctic into the North Atlantic Ocean through Fram Strait. This event induced a significant decrease of Labrador Sea water surface salinity and an abrupt weakening of the Atlantic Meridional Overturning Circulation (AMOC) during the 1970s. These results have implications for the prediction of rapid AMOC changes and indicate that an important part of the atmosphere-ocean dynamics at mid- and high latitudes requires a proper representation of the Fram Strait sea ice transport and of the synoptic scale variability such as atmospheric blocking, which is a challenge for current coupled climate models.

  16. [The possible causes of the tragedy of "Port Famine" in the Strait of Magellan].

    Science.gov (United States)

    Espinoza G, Juan Pablo; Espinoza G, Ricardo

    2010-11-01

    The attempts to colonize the Strait of Magellan soon followed the discovery of this route. PeDro Sarmiento de Gamboa, a Spanish sailor, established human settlements to fortify those lands and control the transit of vessels, especially those of English corsairs, which devastated Chilean and Peruvian coasts. During the summer of 1584, approximately 500 soldiers, artisans, priests, women and children established two villages called "Nombre de Jesús" and "Rey Don Felipe". From the beginning, these settlers had leadership and communication problems and difficulties to obtain food. After three winters only 17 to 18 people survived according to the testimony of one of the survivors, that was rescued by an English sailor named Cavendish, which renamed the village "Rey Don Felipe" as "Port Famine". When he observed the scenes of abandonment and death, he supposed that the settlers died due to lack of food. Other factors that facilitated the desolation were hypothermia, execution, anthropophagy and lesions caused by natives. There is also a possibility that intoxication by red tide (harmful algal bloom) could explain in part the finding of unburied corpses in the strait beaches.

  17. Physical oceanographic mooring data (temperature, salinity, velocity including ADCP ice tracking) collected from Bering Strait Moorings A2,A4, A3 in Bering Strait from 2013-07-05 to 2014-07-02 (NCEI Accession 0156230)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is an archive of data from moorings deployed in Bering Strait from summer 2013 to summer 2014. Mooring deployments were funded by the ONR award N00014-13-1-0468...

  18. Mobile Devices for Tertiary Study--Philosophy Meets Pragmatics for Remote Aboriginal and Torres Strait Islander Women

    Science.gov (United States)

    Townsend, Philip

    2015-01-01

    This paper outlines PhD research which suggests mobile learning fits the cultural philosophies and roles of Aboriginal and Torres Strait Islander women who are preservice teachers in the very remote Australian communities where the research was conducted. The problem which the research addresses is the low completion rates for two community-based…

  19. The Fallacy of the Bolted Horse: Changing Our Thinking about Mature-Age Aboriginal and Torres Strait Islander University Students

    Science.gov (United States)

    Plater, Suzanne; Mooney-Somers, Julie; Lander, Jo

    2015-01-01

    The aim of this article is to critically review and analyse the public representations of mature-age university students in developed and some developing nations and how they compare to the public representations of mature-age Aboriginal and Torres Strait Islander university students in Australia ("students" also refers to graduates…

  20. Residual flow and tidal asymmetry in the Singapore Strait, with implications for resuspension and residual transport of sediment

    NARCIS (Netherlands)

    Van Maren, D.S.; Gerritsen, H.

    2012-01-01

    The Singapore Strait connects the South China Sea, where tides are dominantly diurnal, to the dominantly semidiurnal Indian Ocean. At this transition, the tidal water level oscillations are observed to be semidiurnal while the tidal current oscillations are mixed, diurnal to fully diurnal. Due to

  1. The 1908 Messina Earthquake and the Messina Straits Seismicity as Shallow Expression of Wide Depth-Range Regional Geodynamic Processes

    Science.gov (United States)

    Neri, G.; Orecchio, B.; Presti, D.

    2008-12-01

    New tomographic results in the Calabro-Peloritan Arc region show that the Messina Straits area delineates the transition between the only sector where the Ionian slab is in-depth continuous and therefore still capable to retreat (Southern Calabria) and the south-western boundary of the subduction system now interested by continental collision (central-western Sicily). This geodynamic framework produces the seismogenic stress field detected in the Straits crustal structure, characterised by ESE-oriented extension and by minor strike- slip component. Stress field and seismicity analyses performed in the area reveal that the 1908 earthquake source is characterised by normal faulting, is located in the Straits and it strikes about NNE-SSW with the top below Sicilian shoreline and dip toward east. Also, in spite of the very low seismicity levels recorded since the installation of local seismic network (late '70s), the analysis performed on historical catalogue data (CPTI, http://emidius.mi.ingv.it/CPTI/) for the period 1780-2002 highlights that the Messina Straits is one of the most active areas in Italy, also excluding phases of maximum destructive capability.

  2. Hearing the Voice of Remote Aboriginal and Torres Strait Islander Training Stakeholders Using Research Methodologies and Theoretical Frames of Reference

    Science.gov (United States)

    Guenther, John; Osborne, Sam; Arnott, Allan; McRae-Williams, Eva

    2017-01-01

    Researchers in remote Aboriginal and Torres Strait Islander contexts within Australia are frequently faced with the challenges of working in an intercultural space where channels of communication are garbled with interference created by the complexities of misunderstood worldviews, languages, values and expectations. A concern of many researchers…

  3. Liquid freshwater transport estimates from the East Greenland Current based on continuous measurements north of Denmark Strait

    NARCIS (Netherlands)

    de Steur, L.; Pickart, R.S.; Macrander, A.; Våge, K.; Harden, B.; Jónsson, S.; Østerhus, S.; Valdimarsson, H.

    2017-01-01

    Liquid freshwater transports of the shelfbreak East Greenland Current (EGC) and the separated EGC are determined from mooring records from the Kögur section north of Denmark Strait between August 2011 and July 2012. The 11 month mean freshwater transport (FWT), relative to a salinity of 34.8, was 65

  4. Modeling Evaluation of Tidal Stream Energy and the Impacts of Energy Extraction on Hydrodynamics in the Taiwan Strait

    Directory of Open Access Journals (Sweden)

    Ming-Hsi Hsu

    2013-04-01

    Full Text Available Tidal stream speeds in straits are accelerated because of geographic and bathymetric features. For instance, narrow channels and shallows can cause high tidal stream energy. In this study, water level and tidal current were simulated using a three-dimensional semi-implicit Eulerian-Lagrangian finite-element model to investigate the complex tidal characteristics in the Taiwan Strait and to determine potential locations for harnessing tidal stream energy. The model was driven by nine tidal components (M2, S2, N2, K2, K1, O1, P1, Q1, and M4 at open boundaries. The modeling results were validated with the measured data, including water level and tidal current. Through the model simulations, we found that the highest tidal currents occurred at the Penghu Channel in the Taiwan Strait. The Penghu Channel is an appropriate location for the deployment of a tidal turbine array because of its deep and flat bathymetry. The impacts of energy extraction on hydrodynamics were assessed by considering the momentum sink approach. The simulated results indicate that only minimal impacts would occur on water level and tidal current in the Taiwan Strait if a turbine array (55 turbines was installed in the Penghu Channel.

  5. Backarc basin evolution and cordilleran orogenesis: Insights from new ocean-bottom seismograph refraction profiling in Bransfield Strait, Antarctica

    Science.gov (United States)

    Barker, Daniel H. N.; Christeson, Gail L.; Austin, James A., Jr.; Dalziel, Ian W. D.

    2003-02-01

    Bransfield Strait, a backarc basin off the northwestern Antarctic Peninsula, is a modern analog for Cretaceous basins inverted in the compressional tectonic regime that initiated the Andean Cordillera. Eight new refraction ocean-bottom seismograph profiles in the strait demonstrate that crustal thickness in the deep central basin increases from northeast to southwest, from ˜10 km to ˜14 16 km. This confirms multichannel seismic interpretation of upper crustal structures suggesting that the Bransfield basin is opening by northeast to southwest rift propagation within arc crust of the Antarctic Peninsula, a process also recorded in the obducted Cretaceous Rocas Verdes basin of the southernmost Andes. Thinning is most prominent along the axis of the strait, where the crust is ˜9 11 km thick. In contrast, thicknesses beneath the Antarctic Peninsula margin and the inactive South Shetland Islands pedestal are ˜18 km and ˜24 km, respectively. Seismic velocities and thicknesses suggest that new oceanic crust is not yet being generated. Extension is focused along the northwest margin, imparting the physiographic asymmetry to the strait. Comparing the Bransfield basin with the inverted Rocas Verdes basin and intraoceanic counterparts in the western Pacific suggests that rift propagation and trench-side focusing of extension may be fundamental features of young backarc basins. Resultant asymmetry may facilitate observed obduction of backarc basin floor and arc rocks onto continental margins during compressional orogenesis.

  6. New Approaches to Cross-Strait Integration and Its Impacts on Taiwan’s Domestic Economy: An Emerging “Chaiwan”?

    Directory of Open Access Journals (Sweden)

    Gordon C. K. Cheung

    2010-04-01

    Full Text Available Taiwan’s Legislative Yuan and Presidential elections in January and March 2008 respectively re-orientated cross-Strait relations from hostility to co-operation. On 4 November 2008, Chen Yunlin, head of the Association for Relations Across the Taiwan Straits (ARATS, and Chiang Pin-kun (Jiang Bingkun, chairman of Taiwan’s Straits Exchange Foundation (SEF, meeting in the Second Chiang-Chen Talks in Taiwan, took a historical step in the further development of cross-Strait relations. Agreements were signed on direct air and sea transport, postal services and food-safety security. On 22 December 2009, the Fourth Chiang- Chen Talks took place in Taizhong and more substantial and technical agreements were signed on agriculture, inspection/ accreditation and fisheries. It seems that continuous integration between China and Taiwan is inevitable. To address the implications of this process for Taiwan’s domestic economy, four dimensions of the current cross-Strait relationship are scrutinized: guanxi, plutocracy, legalism and the idea of a Chinese Common Market. It is argued that in order to intensify economic co-operation across the Taiwan Strait, more institutionalization of the cross-Strait relationship must be brought about.

  7. 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

  8. Assessment of circulation and inter-basin transport in the Salish Sea including Johnstone Strait and Discovery Islands pathways

    Science.gov (United States)

    Khangaonkar, Tarang; Long, Wen; Xu, Wenwei

    2017-01-01

    The Salish Sea consisting of Puget Sound and Georgia Basin in U.S and Canadian waters has been the subject of several independent data collection and modeling studies. However, these interconnected basins and their hydrodynamic interactions have not received attention as a contiguous unit. The Strait of Juan de Fuca is the primary pathway through which Pacific Ocean water enters the Salish Sea but the role played by Johnstone Strait and the complex channels northeast of Vancouver Island, connecting the Salish Sea and the Pacific Ocean, on overall Salish Sea circulation has not been characterized. In this paper we present a modeling-based assessment of the two-layer circulation and transport through the multiple interconnected sub-basins within the Salish Sea including the effect of exchange via Johnstone Strait and Discovery Islands. The Salish Sea Model previously developed using the finite volume community ocean model (FVCOM) was expanded over the continental shelf for this assessment encircling Vancouver Island, including Discovery Islands, Johnstone Strait, Broughton Archipelago and the associated waterways. A computational technique was developed to allow summation of volume fluxes across arbitrary transects through unstructured finite volume cells. Tidally averaged volume fluxes were computed at multiple transects. The results were used to validate the classic model of Circulation in Embracing Sills for Puget Sound and to provide quantitative estimates of the lateral distribution of tidally averaged transport through the system. Sensitivity tests with and without exchanges through Johnstone Strait demonstrate that it is a pathway for Georgia Basin runoff and Fraser River water to exit the Salish Sea and for Pacific Ocean inflow. However the relative impact of this exchange on circulation and flushing in Puget Sound Basin is small.

  9. Assessment of circulation and inter-basin transport in the Salish Sea including Johnstone Strait and Discovery Islands pathways

    Energy Technology Data Exchange (ETDEWEB)

    Khangaonkar, Tarang; Long, Wen; Xu, Wenwei

    2017-01-01

    The Salish Sea consisting of Puget Sound and Georgia Basin in U.S and Canadian waters has been the subject of several independent data collection and modeling studies. However, these interconnected basins and their hydrodynamic interactions have not received attention as a contiguous unit. The Strait of Juan de Fuca is the primary pathway through which Pacific Ocean water enters the Salish Sea but the role played by Johnstone Strait and the complex channels northeast of Vancouver Island, connecting the Salish Sea and the Pacific Ocean, on overall Salish Sea circulation has not been characterized. In this paper we present a modeling-based assessment of the two-layer circulation and transport through the multiple interconnected sub-basins within the Salish Sea including the effect of exchange via Johnstone Strait and Discovery Islands. The Salish Sea Model previously developed using the finite volume community ocean model (FVCOM) was expanded over the continental shelf for this assessment encircling Vancouver Island, including Discovery Islands, Johnstone Strait, Broughton Archipelago and the associated waterways. A computational technique was developed to allow summation of volume fluxes across arbitrary transects through unstructured finite volume cells. Tidally averaged volume fluxes were computed at multiple transects. The results were used to validate the classic model of Circulation in Embracing Sills for Puget Sound and to provide quantitative estimates of the lateral distribution of tidally averaged transport through the system. Sensitivity tests with and without exchanges through Johnstone Strait demonstrate that it is a pathway for Georgia Basin runoff and Fraser River water to exit the Salish Sea and for Pacific Ocean inflow. However the relative impact of this exchange on circulation and flushing in Puget Sound Basin is small.

  10. Measuring emotional and social wellbeing in Aboriginal and Torres Strait Islander populations: an analysis of a Negative Life Events Scale

    Directory of Open Access Journals (Sweden)

    Gunthorpe Wendy

    2007-11-01

    Full Text Available Abstract Aboriginal and Torres Strait Islander Australians experience widespread socioeconomic disadvantage and health inequality. In an attempt to make Indigenous health research more culturally-appropriate, Aboriginal and Torres Strait Islander Australians have called for more attention to the concept of emotional and social wellbeing (ESWB. Although it has been widely recognised that ESWB is of crucial importance to the health of Aboriginal and Torres Strait Islander peoples, there is little consensus on how to measure in Indigenous populations, hampering efforts to better understand and improve the psychosocial determinants of health. This paper explores the policy and political context to this situation, and suggests ways to move forward. The second part of the paper explores how scales can be evaluated in a health research setting, including assessments of endorsement, discrimination, internal and external reliability. We then evaluate the use of a measure of stressful life events, the Negative Life Events Scale (NLES, in two samples of Aboriginal people living in remote communities in the Northern Territory of Australia. We argue that the Negative Life Events Scale is a promising assessment of psychosocial wellbeing in Aboriginal and Torres Strait Islander populations. Evaluation of the scale and its performance in other samples of Aboriginal and Torres Strait Islander populations is imperative if we hope to develop better, rather than more, scales for measuring ESWB among Indigenous Australians. Only then will it be possible to establish standardized methods of measuring ESWB and develop a body of comparable literature that can guide both a better understanding of ESWB, and evaluation of interventions designed to improve the psychosocial health of Indigenous populations and decrease health inequalities.

  11. Aboriginal and Torres Strait Islander Worldviews and Cultural Safety Transforming Sexual Assault Service Provision for Children and Young People

    Directory of Open Access Journals (Sweden)

    Leticia Funston

    2013-08-01

    Full Text Available Child Sexual Assault (CSA in Aboriginal and Torres Strait Islander communities is a complex issue that cannot be understood in isolation from the ongoing impacts of colonial invasion, genocide, assimilation, institutionalised racism and severe socio-economic deprivation. Service responses to CSA are often experienced as racist, culturally, financially and/or geographically inaccessible. A two-day forum, National Yarn Up: Sharing the Wisdoms and Challenges of Young People and Sexual Abuse, was convened by sexual assault services to identify the main practice and policy concerns regarding working with Aboriginal and Torres Strait Islander children and young people (C&YP, families and communities in the context of CSA. The forum also aimed to explore how services can become more accountable and better engaged with the communities they are designed to support. The forum was attended by eighty invited Aboriginal and Torres Strait Islander and non-Aboriginal youth sexual assault managers and workers representing both “victim” and “those who sexually harm others” services. In keeping with Aboriginal Community-Based Research methods forum participants largely directed discussions and contributed to the analysis of key themes and recommendations reported in this article. The need for sexual assault services to prioritise cultural safety by meaningfully integrating Aboriginal and Torres Strait Islander Worldviews emerged as a key recommendation. It was also identified that collaboration between “victims” and “those who sexually harm” services are essential given Aboriginal and Torres Strait Islander C&YP who sexually harm others may have also been victims of sexual assault or physical violence and intergenerational trauma. By working with the whole family and community, a collaborative approach is more likely than the current service model to develop cultural safety and thus increase the accessibility of sexual assault services.

  12. Physical characteristic of brown algae (Phaeophyta from madura strait as irreversible hydrocolloid impression material

    Directory of Open Access Journals (Sweden)

    Prihartini Widiyanti

    2012-09-01

    Full Text Available Background: Brown algae is a raw material for producing natrium alginates. One type of brown algae is Sargassum sp, a member of Phaeophyta division. Sargassum sp could be found in Madura strait Indonesia. Natrium alginate can be extracted from Sargassum sp. The demand of alginate in Indonesia is mainly fulfilled from abroad, meanwhile Sargassum sp is abundantly available. Purpose: The purpose of study were to explore the potency of brown alga Sargassum sp from Madura strait as hydrocolloid impression material and to examine its physical characteristic. Methods: The methods of research including extraction natrium alginate from Sargassum sp, synthesis of dental impression material and the test of porosity, density, viscosity, and water content of impression material which fulfilled the standard of material used in clinical application in dentistry. Results: Extraction result of Sargassum sp was natrium alginate powder with cream colour, odorless, and water soluble. The water content of natrium alginate was 21.64% and the viscosity was 0.7 cPs. The best porosity result in the sample with the addition of trinatrium phosphate 4% was 3.61%. Density value of impression material was 3 gr/cm3. Conclusion: The research suggested that brown algae Sargassum sp from Madura strait is potential as hydrocolloid impression material, due to its physical properties which close to dental impression material, but still need further research to optimize the physical characteristic.Latar belakang: Alga coklat adalah sumber bahan baku material natrium alginat. Salah satu jenis alga coklat adalah Sargassum sp yang merupakan anggota divisi Phaeophyta. Sargassum sp dapat ditemukan di Selat Madura Indonesia. Natrium alginat dapat diekstraksi dari Sargassum sp. Kebutuhan akan bahan ini di Indonesia sebagian besar dipenuhi dari impor, padahal ketersediaan Sargassum sp di Indonesia sangat melimpah. Tujuan: Penelitian ini bertujuan untuk mengeksplorasi potensi alga coklat

  13. Upper-crustal structure beneath the strait of Georgia, Southwest British Columbia

    Science.gov (United States)

    Dash, R.K.; Spence, G.D.; Riedel, M.; Hyndman, R.D.; Brocher, T.M.

    2007-01-01

    We present a new three-dimensional (3-D) P-wave velocity model for the upper-crustal structure beneath the Strait of Georgia, southwestern British Columbia based on non-linear tomographic inversion of wide-angle seismic refraction data. Our study, part of the Georgia Basin Geohazards Initiative (GBGI) is primarily aimed at mapping the depth of the Cenozoic sedimentary basin and delineating the near-surface crustal faults associated with recent seismic activities (e.g. M = 4.6 in 1997 and M = 5.0 in 1975) in the region. Joint inversion of first-arrival traveltimes from the 1998 Seismic Hazards Investigation in Puget Sound (SHIPS) and the 2002 Georgia Basin experiment provides a high-resolution velocity model of the subsurface to a depth of ???7 km. In the southcentral Georgia Basin, sedimentary rocks of the Cretaceous Nanaimo Group and early Tertiary rocks have seismic velocities between 3.0 and 5.5 km s-1. The basin thickness increases from north to south with a maximum thickness of 7 (??1) km (depth to velocities of 5.5 km s-1) at the southeast end of the strait. The underlying basement rocks, probably representing the Wrangellia terrane, have velocities of 5.5-6.5 km-1 with considerable lateral variation. Our tomographic model reveals that the Strait of Georgia is underlain by a fault-bounded block within the central Georgia Basin. It also shows a correlation between microearthquakes and areas of rapid change in basin thickness. The 1997/1975 earthquakes are located near a northeast-trending hinge line where the thicknesses of sedimentary rocks increase rapidly to the southeast. Given its association with instrumentally recorded, moderate sized earthquakes, we infer that the hinge region is cored by an active fault that we informally name the Gabriola Island fault. A northwest-trending, southwest dipping velocity discontinuity along the eastern side of Vancouver Island correlates spatially with the surface expression of the Outer Island fault. The Outer Island

  14. Parasites of the hard clam Meretrix meretrix Linnaeus from Western Johor Straits, Malaysian

    Science.gov (United States)

    Azmi, Nur Fauzana; Ghaffar, Mazlan Abd.; Cob, Zaidi Che

    2014-09-01

    This study describes the apicomplexa as well as other parasites infecting organs/tissues of the hard clam Meretrix meretrix Linnaeus, from Merambong Shoal, Western Johor Straits, Malaysia. Samples were collected randomly by hand picking, in November and December 2013. Histological techniques were performed, stained using Masson's Trichrome protocol and observed under light microscope. The results showed that gonad and gill were the most infected organs followed by digestive gland, intestine and adductor muscle. No pathology condition was observed in the mantle. Histophatological examination showed that the gregarine, Nematopsis, unidentified coccidian and Perkinsus were found in the gill and gonad, and also in the numerous hemocytes. Other pathological conditions such as bacteria-like inclusion and intracellular bacteria were also observed in the same organs. Further investigations are needed particularly on other molluscs present at the study area. Understanding the morphology and pathology of parasites infecting mollusks are very important for management of the resources.

  15. The Straits Chinese Contribution to Malaysian Literary Heritage: Focus on Chinese Stories Translated into Baba Malay

    Directory of Open Access Journals (Sweden)

    S.K. Yoong

    2004-12-01

    Full Text Available The Chinese born in the Straits Settlements of Peninsula Malaya (Penang, Singapore, Malacca are called Babas to distinguish them from those born in China. The Babas are rooted from three different races, Chinese, Malay and English and as such their lifestyles show a mixed blend of the Chinese, Malay and European cultures. Because of this cultural background, the Babas exhibited a unique cultural mix in the clothes they wear, their culinary skills, architectural styles, language and literature. The paper describes the characteristics of 68 Baba translated works published between 1889 and 1950; focusing on the publication trends between the period under study, the persons involved in the creative output, the publishers and printers involved, the contents of the translated works, the physical make-up of the works and the libraries where these works are held.

  16. Appropriate Health Promotion for Australian Aboriginal and Torres Strait Islander Communities

    DEFF Research Database (Denmark)

    Demaio, Alessandro Rhyll; Drysdale, Marlene; de Courten, Maximilian

    2012-01-01

    Health promotion for Australian Aboriginal and Torres Strait Islander communities and their people has generally had limited efficacy and poor sustainability. It has largely failed to recognise and appreciate the importance of local cultures and continues to have minimal emphasis on capacity...... building, community empowerment and local ownership. Culturally-Appropriate Health Promotion is a framework of principles developed in 2008 with the World Health Organization (Geneva) and Global Alliance for Health Promotion. It guides community-focused health promotion practice built on and shaped...... by the respect, understanding and utilisation of local knowledge and culture. Culturally-Appropriate Health Promotion is not about ‘targeting’, ‘intervening’ or ‘responding’. Rather, it results in health program planners and policy-makers understanding, respecting, empowering and collaborating with communities...

  17. Plastic debris and microplastics along the beaches of the Strait of Hormuz, Persian Gulf.

    Science.gov (United States)

    Naji, Abolfazl; Esmaili, Zinat; Khan, Farhan R

    2017-01-30

    Currently little is known about the prevalence of plastics and microplastics (MPs) in the Persian Gulf. Five sampling stations were selected along the Strait of Hormuz (Iran) that exhibited different levels of industrialization and urbanization, and included a marine protected area. Debris was observed and sediments were collected for MPs extraction via fluidization/floatation methodology. The order of MP abundance (par/kg) generally reflected the level of anthropogenic activity: Bostanu (1258±291)>Gorsozan (122±23)>Khor-e-Yekshabeh (26±6)>Suru (14±4)>Khor-e-Azini (2±1). Across all sites fibers dominated (83%, 11% film, 6% fragments). FT-IR analysis showed polyethylene (PE), nylon, and PET (polyethylene terephthalate) were the commonly recovered polymers. Likely sources include beach debris, discarded fishing gear, and urban and industrial outflows that contain fibers from clothes. This study provides a 'snapshot' of MP pollution and longitudinal studies are required to fully understand plastic contamination in the region.

  18. Mitochondrial DNA haplotyping of Testudo graeca on both continental sides of the Straits of Gibraltar.

    Science.gov (United States)

    Alvarez, Y; Mateo, J A; Andreu, A C; Díaz-Paniagua, C; Diez, A; Bautista, J M

    2000-01-01

    Testudo graeca is an endangered species of tortoise that inhabits Mediterranean areas of Africa, Asia, and Europe. Western populations are found on both sides of the Straits of Gibraltar. The effects of geographical isolation on genetic divergence were assessed by the sequence analysis of two mitochondrial DNA regions of the 12S rRNA and cytochrome b genes. Four different haplotypes were identified. A single haplotype was shared by all Spanish and some east Moroccan specimens. Two haplotypes were unique to the west Moroccan T. graeca populations and allowed the clear discrimination between individual specimens found west of the Moulouya River. Phylogenetic analysis based on the estimation of nucleotide sequence distances of the haplotypes suggests an African origin for the Spanish populations and a subspecies status for the west Moroccan pool.

  19. Meteorologically-driven circulation and flushing times of the Bay of Algeciras, Strait of Gibraltar.

    Science.gov (United States)

    Sánchez-Garrido, José C; Lafuente, Jesús García; Sammartino, Simone; Naranjo, Cristina; de los Santos, Francisco J; Álvarez Fanjul, Enrique

    2014-03-15

    A primitive-equation model has been used to investigate the meteorologically-driven circulation of the Bay of Algeciras. It is shown that the mean circulation of Atlantic Water (AW) is characterized by an anticyclonic cell, while Mediterranean Water (MW) follows a preferred cyclonic pathway. Meteorological forcing distorts substantially the AW mean circulation pattern, and only modulates that of the MW. Winds drive a vertical circulation cell in the Atlantic layer consistent with Ekman dynamics, whereas the horizontal circulation pattern is markedly dependent on the swift Atlantic jet entering the Mediterranean and changes from clearly anticyclonic to cyclonic as the jet separates or approaches the strait's northern shoreline. This occurs through atmospheric pressure-driven acceleration/deceleration of the jet, in agreement with internal hydraulics theory predictions. It is also found that the renewal of AW is largely modulated by tides, with meteorological forcing playing a secondary role. The opposite applies to the renewal of MW.

  20. Test of numerical prediction of sea water temperature in the Taiwan Strait

    Institute of Scientific and Technical Information of China (English)

    Wang Xiuqin; Huang Huowang; Dong Jian; Qian Chengchun

    2001-01-01

    A dynamic numerical prediction model of sea water temperature for limited sea area is used to predict the sea water temperature at the sea area near Fujian. Essential adjustments have been made in accordance with the characteristics of this region. Two tests have been made. One is in summer (3 d) and the other is in winter (10 d). In the summer test, a typhoon is just passing by and the calculated current field well responds to typhoon. In the winter test, variation tendency of the predicted sea water temperature field agrees with that of the observation basically, the absolute mean error in the whole sea area is 0.6 ℃. The variation of the sea water temperature is mostly affected by entrainment and pumping, which is related to the topography of the strait.

  1. Statistical analysis of strait time index and a simple model for trend and trend reversal

    Science.gov (United States)

    Chen, Kan; Jayaprakash, C.

    2003-06-01

    We analyze the daily closing prices of the Strait Time Index (STI) as well as the individual stocks traded in Singapore's stock market from 1988 to 2001. We find that the Hurst exponent is approximately 0.6 for both the STI and individual stocks, while the normal correlation functions show the random walk exponent of 0.5. We also investigate the conditional average of the price change in an interval of length T given the price change in the previous interval. We find strong correlations for price changes larger than a threshold value proportional to T; this indicates that there is no uniform crossover to Gaussian behavior. A simple model based on short-time trend and trend reversal is constructed. We show that the model exhibits statistical properties and market swings similar to those of the real market.

  2. On extreme atmospheric and marine nitrogen fluxes and chlorophyll-a levels in the Kattegat Strait

    DEFF Research Database (Denmark)

    Hasager, C.B.; Carstensen, J.; Ellermann, T.

    2003-01-01

    A retrospective analysis is carried out to investigate the importance of the vertical fluxes of nitrogen to the marine sea surface layer in which high chlorophyll a levels may cause blooms of harmful algae and subsequent turn over and oxygen depletion at the bottom of the sea. Typically nitrogen...... are calculated by the periodic maximum method and the results are successfully compared to a map of chlorophyll return periods based on in-situ observations. The one-year return of extreme atmospheric wet deposition is around 60 mg N m(-2) day(-1) and 30 mg N m(-2) day(-1) for deep-water entrainment. Atmospheric......-water entrainment forced by high winds greatly exceeds the atmospheric pool of nitrogen washed out by precipitation. At the frontal zone of the Kattegat Strait and Skagerrak, the nitrogen deep-water entrainment is very high and this explains the high 10-year return chlorophyll level at 8 mg m(-3) in the Kattegat...

  3. Probability Models for the Distribution of Copepods in Different Coastal Ecosystems Along the Straits of Malacca

    Science.gov (United States)

    Matias-Peralta, Hazel Monica; Ghodsi, Alireza; Shitan, Mahendran; Yusoff, Fatimah Md.

    Copepods are the most abundant microcrustaceans in the marine waters and are the major food resource for many commercial fish species. In addition, changes in the distribution and population composition of copepods may also serve as an indicator of global climate changes. Therefore, it is important to model the copepod distribution in different ecosystems. Copepod samples were collected from three different ecosystems (seagrass area, cage aquaculture area and coastal waters off shrimp aquaculture farm) along the coastal waters of the Malacca Straits over a one year period. In this study the major statistical analysis consisted of fitting different probability models. This paper highlights the fitting of probability distributions and discusses the adequateness of the fitted models. The usefulness of these fitted models would enable one to make probability statements about the distribution of copepods in three different ecosystems.

  4. The Application of Fucus vesiculosus as a Bioindicator of 60Co Concentrations in the Danish Straits

    DEFF Research Database (Denmark)

    Boelskifte, S.

    1985-01-01

    The occurrence of 60Co in the Danish Straits is investigated by applying the seaweed Fucus vesiculosus as a bioindicator. In order to describe different dispersion situations, three areas have been studied separately: the North Sea, where it is possible to measure 60Co from sources in France and....../or the UK; the Kattegat, where the sources are the Swedish nuclear power plants Ringhals and Barsebäck; and the Sound, where the initial mixing of the release from Barsebäck takes place. A power function can be estimated for the Kattegat and the Sound describing the content of 60Co in Fucus as a function...... of distance from Barsebäck. Problems of uncertainty related to differences in environmental parameters are discussed and new investigations to improve the use of Fucus as a bioindicator are suggested....

  5. A shark in the stars: astronomy and culture in the Torres Strait

    CERN Document Server

    Hamacher, Duane W

    2014-01-01

    Technology has, without doubt, expanded our understanding of space. The Voyager 1 space probe is on the brink of leaving our solar system. Massive telescopes have discovered blasts of fast radio bursts from 10 billion light years away. And after a decade on Mars, a Rover recently found evidence for an early ocean on the Red Planet. But with every new advance, it's also important to remember the science of astronomy has existed for thousands of years and forms a vital part of Indigenous Australian culture, even today. As an example, let's explore the astronomy of the Torres Strait Islanders, an Indigenous Australian people living between the tip of Cape York and Papua New Guinea.

  6. Occurrence of polycyclic aromatic hydrocarbons (PAHs) in seawater from the Western Taiwan Strait, China.

    Science.gov (United States)

    Wu, Yu-Ling; Wang, Xin-Hong; Li, Yong-Yu; Hong, Hua-Sheng

    2011-01-01

    Seawater samples (including surface water and bottom water) were collected from the Western Taiwan Strait (WTS) during June 24-25, 2009; polycyclic aromatic hydrocarbons (PAHs) in dissolved phase and particulate phase were analyzed, respectively. The results showed that the total concentrations of PAHs in the dissolved phase and particulate phase were ranged from 12.3 to 58.0 ng L(-1), and 10.3-45.5 ng L(-1), which showed a low-middle contamination level in the China Seas. The spatial variability of PAHs may be related to the complicated currents of WTS, especially the Min-Zhe coastal current. PAHs diagnostic ratios suggested that PAHs mainly originated from the inputs of pyrolytic (combustion) sources, which might be contributed to land-based atmospheric deposition. The particle-water partition coefficients of individual PAH showed that partitions were not correlated with suspended particulate matter content, dissolved organic carbon or salinity, similar to the Yangtze coastal area.

  7. Manganese, nickel, selenium and cadmium in molluscs from the Magellan Strait, Chile.

    Science.gov (United States)

    Astorga España, M S; Rodríguez Rodríguez, E M; Díaz Romero, C

    2004-08-01

    The concentrations of manganese, selenium, nickel and cadmium were determined in 112 samples of molluscs belonging to mussels (Mytilus chilensis, n = 47) and limpets (Nacella deaurata, n = 65), which were collected from the coastline of the Magellan Strait, Chile. Four (6.2%) samples of limpets exceeded the maximum limits for cadmium established in Europe. Limpets showed higher mean manganese, nickel and cadmium concentrations than mussels, whilst the mean selenium concentration in mussels was higher. The consumption of one serving (100 g) of molluscs represents a considerable contribution to the dietary daily intake of selenium, and limpets make a significant contribution to the manganese and cadmium intakes. The sampling zone influenced the trace element concentrations, and different uptakes were observed between the mollusc species.

  8. Tectonic activity and the evolution of submarine canyons: The Cook Strait Canyon system, New Zealand

    Science.gov (United States)

    Micallef, Aaron; Mountjoy, Joshu; Barnes, Philip; Canals, Miquel; Lastras, Galderic

    2016-04-01

    Submarine canyons are Earth's most dramatic erosional features, comprising steep-walled valleys that originate in the continental shelf and slope. They play a key role in the evolution of continental margins by transferring sediments into deep water settings and are considered important biodiversity hotspots, pathways for nutrients and pollutants, and analogues of hydrocarbon reservoirs. Although comprising only one third of continental margins worldwide, active margins host more than half of global submarine canyons. We still lack of thorough understanding of the coupling between active tectonics and submarine canyon processes, which is necessary to improve the modelling of canyon evolution in active margins and derive tectonic information from canyon morphology. The objectives of this study are to: (i) understand how tectonic activity influences submarine canyon morphology, processes, and evolution in an active margin, and (2) formulate a generalised model of canyon development in response to tectonic forcing based on morphometric parameters. We fulfil these objectives by analysing high resolution geophysical data and imagery from Cook Strait Canyon system, offshore New Zealand. Using these data, we demonstrate that tectonic activity, in the form of major faults and structurally-generated tectonic ridges, leaves a clear topographic signature on submarine canyon location and morphology, in particular their dendritic and sinuous planform shapes, steep and linear longitudinal profiles, and cross-sectional asymmetry and width. We also report breaks/changes in canyon longitudinal slope gradient, relief and slope-area regression models at the intersection with faults. Tectonic activity gives rise to two types of knickpoints in the Cook Strait Canyon. The first type consists of low slope gradient, rounded and diffusive knickpoints forming as a result of short wavelength folds or fault break outs and being restored to an equilibrium profile by upstream erosion and

  9. FCJ-140 Radio Feeds, Satellite Feeds, Network Feeds: Subjectivity Across the Straits of Gibraltar.

    Directory of Open Access Journals (Sweden)

    Nicholas Knouf

    2012-07-01

    Full Text Available This paper engages with the practices surrounding the two fadaiat encounters that took place simultaneously in Spain and Morocco in the summers of 2004 and 2005 (see http://fadaiat.net/ .  The fadaiat project focused on the question of immigration to Europe, specifically from northern Africa, and the ‘Fortress Europe’ responses by European Union governments.  Participants in fadaiat included academic scholars, free software developers, artists, and activists, forming a meta-network that created bridges across disparate communities and practices.  In particular, the participation of the Spanish collective hackitectura was key; they describe themselves as a ‘posse of architects, hackers and social activists experimenting in the merging territories of recombining spatial cyborgs composed by physical spaces, ICT networks and bodies’.  hackitectura led the development of both a temporary civil, non-commercial wireless link across the straits of Gibraltar between Tarifa, Spain and Tangier, Morocco, as well as an entirely free software audio/video streaming system, that enabled participants on both sides to come together independently of the restrictions normally placed on such movement by immigration laws.The importance of free software for fadaiat extends beyond its purely instrumental use as an agent for disrupting state control.  Indeed, the imagery of computation and free software – networks, links, patches, nodes, penguins – pervades the documentation of the project.  Rave parties simulcast across the straits are as important as the discussions and software produced.  I suggest that this can be understood as developing new forms of subjectivity, in the sense given by Felix Guattari, and therefore link the fadaiat project to earlier pirate radio practices, especially Radio Alice in Bologna, Italy, in which Guattari was involved.

  10. The Strait of Gibraltar as a major biogeographic barrier in Mediterranean conifers: a comparative phylogeographic survey.

    Science.gov (United States)

    Jaramillo-Correa, J P; Grivet, D; Terrab, A; Kurt, Y; De-Lucas, A I; Wahid, N; Vendramin, G G; González-Martínez, S C

    2010-12-01

    The Strait of Gibraltar (SG) is reputed for being both a bridge and a geographic barrier to biological exchanges between Europe and Africa. Major genetic breaks associated with this strait have been identified in various taxa, but it is unknown whether these disjunctions have been produced simultaneously or by independent biogeographic processes. Here, the genetic structure of five conifers distributed on both sides of the SG was investigated using mitochondrial (nad1 b/c, nad5-1, nad5-4 and nad7-1) and chloroplast (Pt1254, Pt15169, Pt30204, Pt36480, Pt71936 and Pt87268) DNA markers. The distribution of genetic variation was partially congruent between types of markers within the same species. Across taxa, there was a significant overlapping between the SG and the genetic breaks detected, especially for the four Tertiary species surveyed (Abies pinsapo complex, Pinus nigra, Pinus pinaster and Taxus baccata). For most of these taxa, the divergence of populations across the SG could date back to long before the Pleistocene glaciations. However, their strongly different cpDNA G(ST) and R(ST) values point out that they have had dissimilar population histories, which might include contrasting amounts of pollen-driven gene flow since their initial establishment in the region. The fifth species, Pinus halepensis, was genetically depauperated and homogenous on both sides of the SG. A further analysis of nuclear DNA sequences with coalescent-based isolation with migration models suggests a Pleistocene divergence of P. halepensis populations across the SG, which is in sharp contrast with the pre-Pleistocene divergence dates obtained for P. pinaster. Altogether, these results indicate that the genetic breaks observed across this putative biogeographical barrier have been produced by independent evolutionary processes related to the biological history of each individual species instead of a common vicariant phenomenon.

  11. Ten years of marine current measurements in Espartel Sill, Strait of Gibraltar

    Science.gov (United States)

    Sammartino, S.; García Lafuente, J.; Naranjo, C.; Sánchez Garrido, J. C.; Sánchez Leal, R.; Sánchez Román, A.

    2015-09-01

    More than 10 year of Acoustic Doppler Current Profiler observations collected at the westernmost sill (Espartel sill) of the Strait of Gibraltar by a monitoring station have been carefully processed to provide the most updated estimation of the Mediterranean outflow. A comprehensive quality control of the factors affecting the uncertainty of the measurements has been carried out and great care has been paid to infer the current at the bottom layer, where direct observations are lacking. The mean outflow in the southern channel of the sill section has been estimated as -0.82 Sv (1 Sv = 1 × 106 m3 s-1), with an average contribution of the eddy fluxes of -0.04 Sv. This figure is an overestimation, as the mooring measurements, assumed valid for the whole section, ignore the lateral friction. On the other hand, it only gives the flow through the southern channel and disregards the fraction flowing through shallower northern part. Both drawbacks have been addressed by investigating the cross-strait structure of the outflow from hindcasts produced by the MITgcm numerical model, run in a high-resolution domain covering the Gulf of Cádiz and Alboran Sea basins. An overall rectifying factor of 1.039 was found satisfactory to correct the first estimate, so that the final mean outflow computed from this data set is -0.85 Sv, complemented with an uncertainty of ±0.03 Sv based on the interannual variability of the series. The temporal analysis of the series shows an outflow seasonality of around the 8% of the mean value, with maximum outflow in early spring.

  12. Spatial localization and mesoscale modulation of mixing and transformation of the Denmark Strait Overflow

    Science.gov (United States)

    Koszalka, Inga; Haine, Thomas; Magaldi, Marcello

    2015-04-01

    The Denmark Strait Overflow (DSO) is a major export route for dense waters from the Nordic Seas forming the North Atlantic Deep Water, an important element of the climate system. Mixing processes in the Irminger Basin determine volume transport and properties of the DSO but are poorly resolved by sparse observations which hinders development of DSO mixing parameterizations in global circulation models (GCMs). We employ a high resolution circulation model (horizontal grid spacing of 2km and 210 levels in the vertical) to investigate transformation and mixing in the DSO in the Irminger Basin and quantify the effect of mesoscale (10-100km) flows unresolved by GCMs. Both the warming rate derived from model Lagrangian particles and the Eulerian eddy temperature flux divergence show elevated values in about a 200km long and 50km wide corridor downstream of the Denmark Strait sill and between the shelf break and the 2000m isobath. In this region, the DSO warms by about 1K, which constitutes most of the transformation along the entire 700km pathway in the Irminger Basin. The horizontal and vertical mixing is modulated by dense water boluses and overlying cyclonic eddies that propagate together through the Irminger Basin (`beddies'). The passage of beddies increase the squared vertical shear of horizontal velocity by a factor of 3, correspond to increase in the vertical velocity by ten times and double the eddy heat flux divergence leading to a warming of the bottom (densest) waters and a cooling of the interface layer of the overflow plume and the ambient water above. There is a clear correlation between the speed in the nose of the plume, the eddy kinetic energy and the vertical shear in the horizontal flow. The modulation of mixing by the mesoscale variability and the attendant mixing localization should be included in future overflow parameterizations in global circulation models. A targeted field campaign to empirically test these conjectures is another high priority.

  13. STUDY OF CORAL REEF DISTRIBUTION AROUND BADUNG STRAIT USING ALOS SATELLITE DATA

    Directory of Open Access Journals (Sweden)

    Suciati -

    2012-11-01

    Full Text Available Coral reef ecosystem has become a centre of interest because of the development of marine tourism development,coral fragment trade, and other activities that are able to destroy coral reef ecosystem. ALOS with AVNIR-2 sensor wasselected because it has 3 visible spectrums which have the ability of penetration into water column, also it have highenough of spatial resolution i.e.10 meters.The aims of this research are: 1 to identify the level of accuracy of ALOS satellite image in activity for coral reefdistribution mapping and 2 to identify the general condition of coral reefs in around Badung Strait.Preliminary processes of image processing are geometric correction and atmosphere correction. Water columneffect was reduced by Lyzenga Algorithm. Five classes were determined by multispectral classification process e.i. coral,vegetation, sand, rubble of coral and substrate. Ground check was done to identify the accuracy level. The methodaccuracy by Lillesand and Kiefer was used in this research.The result of accuracy test shows that classification accuracy was 87.16% for overall accuracy. Results of imageinterpretation show that live coral in around Badung strait is estimated to have about 141,056 hectares width. It wascovering Denpasar Regency in the east and south-east side of Serangan Island with the fringing reef type; KlungkungRegency in the west side of Lembongan Island with the fringing reef type and in the south side with the platform type,while in Gianyar Regency was not found the coral reef distribution.

  14. The potential impact of bedform migration on seagrass communities in Torres Strait, northern Australia

    Science.gov (United States)

    Daniell, James J.; Harris, Peter T.; Hughes, Michael G.; Hemer, Mark; Heap, Andrew

    2008-09-01

    Seagrass communities in the northwest of Torres Strait are known to disappear episodically over broad areas. Sediment mobility surveys were undertaken within two study areas during the monsoon and trade wind seasons, in the vicinity of Turnagain Island, to find out if the migration of bedforms could explain this disappearance. The two study areas covered sand bank and sand dune environments to compare and contrast their migration characteristics. Repeat multibeam sonar surveys were used to measure dune-crest migration during each season. Our results show that seagrass beds occur in the troughs of sediment-starved dunes, but no seagrass occurs in association with full-bedded dunes that are superimposed on large sand bank features. The coincidence of seagrass beds with the sediment-starved dunes is in spite of the fact that they migrate faster (0.59 m day -1) than full-bedded dunes (0.13 m day -1), which indicates that some other factor (other than dune migration rate) limits seagrass growth within Torres Strait. We suggest that seagrasses are unable to colonise full-bedded dunes because of the semi-continuously transported sand that characterises this environment. In contrast, the troughs of sediment-starved dunes experience only limited bedload transport and are less hostile for seagrasses. A conceptual model is presented to explain the occurrence of seagrass beds in relation to their proximity to migrating sand dunes. Based on our analysis, we conclude that the widespread dieback of seagrasses documented for the Turnagain Island region was not caused by dune migration.

  15. Broadband waveform inversion of moderate earthquakes in the Messina Straits, southern Italy

    Science.gov (United States)

    D'Amico, Sebastiano; Orecchio, Barbara; Presti, Debora; Zhu, Lupei; Herrmann, Robert B.; Neri, Giancarlo

    2010-04-01

    We report the first application of the Cut and Paste (CAP) method to compute earthquake focal mechanisms in the Messina Straits area by waveform inversion of Pnl and surface wave segments. This application of CAP has furnished new knowledge about low-magnitude earthquake mechanics that will be useful for improved understanding of the local geodynamics. This is possible because the CAP inversion technique can be applied to small earthquakes, for which traditional moment tensor inversion methods are not appropriate and P-onset focal mechanisms in the study area fail because of a lack of sufficient observations. We estimate the focal mechanisms of 23 earthquakes with local magnitudes in the range of 3-4 occurring in the 2004-2008 time period, and recorded by the broadband stations of the Italian National Seismic Network and the Mediterranean Very Broadband Seismographic Network (MedNet) run by the Istituto Nazionale di Geofisica e Vulcanologia (INGV). The solutions show that normal faulting is the prevailing style of seismic deformation in the northern part of the study area while co-existence of normal faulting and strike-slip has been detected in the southern part. In the whole area of investigation the T-axes of focal mechanisms display a preferential northwest-southeast direction of extension. Combined with the findings of previous investigations, this improved database of focal mechanisms allows us to better detail the transitional area between the extensional domain related to subduction trench retreat (southern Calabria) and the compressional one associated with continental collision (western-central Sicily). The observed spatial change of seismic deformation regime offers new data to current seismotectonic and seismic hazard investigations in the area of Messina Straits where a magnitude 7.2 earthquake caused more than 60,000 casualties on 28 December 1908.

  16. Sediment characteristics and provenance of the Taiwan Shoal in the southern Taiwan Strait

    Science.gov (United States)

    Koo, W. S.; Lin, A. T.; Kuo, L. W.; Lee, Y. H.

    2016-12-01

    The Taiwan Shoal in the southern Taiwan Strait exhibits a lobe-shaped shallow water area, with a depth less than around 40 m and an area approximately of 13,000 km2. The Shoal consists of relict sediments remnant from deltaic deposits during the last glacial period and associated with the paleo-Min River. We collected seafloor sediments in and around the Taiwan Shoal to study the sediment characteristics and provenance of the Shoal as well as Taiwanese river sediments to characterize sediment sourced from southern Taiwan. Our results help to understand possible sediment delivery pathways in a source-to-sink context from the southern Taiwan Strait to the northern South China Sea. The method of X-ray diffraction is used to identify mineral compositions for muds and mineral compositions are examined under polarized microscope for sands. Zircon grains are separated from heavy minerals for U-Pb dating in order to understand the sediment source terranes. Sediments of the Taiwan Shoal are mostly tawny-colored, medium to coarse-grained sands with abundant shell fragments and shallow-water benthic foraminifera. Sediments to the south of the Taiwan Shoal and in the outer shelf consist of dark brown-colored and fine-grained sands with rare shell fragments. Siliciclastic compositions of the Taiwan Shoal sediments are mostly quartz. The second abundant composition is rock fragments with more occurrences near the Chinese coastline and the Penghu archipelago. Slate fragments are found to occur near Taiwan, especially in the Penghu Channel area. Clay minerals from the Penghu Channels and south of the Taiwan Shoal are dominated by illite and chlorite with minor smectite and kaolinite. The sediment colors and mineral species are very different for the sediments of the Taiwan Shoal and outer shelf, revealing that these two areas featuring different oceanographic processes and sediment provenance.

  17. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Puget Sound and Strait of Juan de Fuca, Washington: M_MAMPT (Marine Mammal Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for sea otters, sea lions, and harbor seals in Puget Sound and Strait of Juan de Fuca, Washington. Vector...

  18. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Puget Sound and Strait of Juan de Fuca, Washington: SOCECON (Socioeconomic Resource Points and Lines)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains points that represent the following sensitive human-use socioeconomic sites in Puget Sound and the Strait of Juan de Fuca, Washington: access...

  19. Physical, biological and optical oceanographic data collected from moored buoys in the Bering Strait from 08/16/2004 to 09/03/2007 (NODC Accession 0045300)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Physical, current meter, biological, and optical oceanographic data were collected in the Bering Strait from August 16, 2004 to September 3, 2007. These data were...

  20. Environmental Sensitivity Index (ESI) Atlas: Puget Sound and Strait of Juan de Fuca, maps and geographic information systems data (NODC Accession 0013952)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) data for the Puget Sound and Strait of Juan de Fuca from 1978 to 2006. ESI data characterize...

  1. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Puget Sound and Strait of Juan de Fuca, Washington: MGT (Management Area Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains polygons that represent the following sensitive human-use management areas in Puget Sound and the Strait of Juan de Fuca, Washington:...

  2. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Puget Sound and Strait of Juan de Fuca, Washington: NESTS (Nest Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for bald eagle, great blue heron, and seabird nesting sites in Puget Sound and Strait of Juan de Fuca,...

  3. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Puget Sound and Strait of Juan de Fuca, Washington: HABITATL (Habitat Lines)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine and estuarine vegetation in Puget Sound and Strait of Juan de Fuca, Washington. Vector lines in...

  4. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Puget Sound and Strait of Juan de Fuca, Washington: HABITATS (Habitat Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine and estuarine vegetation in Puget Sound and Strait of Juan de Fuca, Washington. Vector polygons...

  5. Assessment of Radiation and Heavy Metals Risk due to the Dietary Intake of Marine Fishes (Rastrelliger kanagurta) from the Straits of Malacca: e0128790

    National Research Council Canada - National Science Library

    M U Khandaker; Kh Asaduzzaman; S M Nawi; A R Usman; Y M Amin; E Daar; D A Bradley; H Ahmed; A A Okhunov

    2015-01-01

      The environment of the Straits of Malacca receives pollution as a result of various industrial and anthropogenic sources, making systematic studies crucial in determining the prevailing water quality...

  6. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Puget Sound and Strait of Juan de Fuca, Washington: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for forage fish in Puget Sound and Strait of Juan de Fuca, Washington. Vector polygons in this data set...

  7. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Puget Sound and Strait of Juan de Fuca, Washington: INVERT (Invertebrate Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for clams, oysters, crabs, and other invertebrate species in Puget Sound and Strait of Juan de Fuca,...

  8. Current speed and direction, temperature and salinity collected from Moored Buoy in Davis Strait from 1987-09-05 to 1990-09-06 (NCEI Accession 0129882)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Volume, freshwater and heat transport through Davis Strait, the northern boundary of the Labrador Basin, were computed using a mooring array deployed for three...

  9. Enhancing national data to align with policy objectives: Aboriginal and Torres Strait Islander smoking prevalence at finer geographic levels.

    Science.gov (United States)

    Wright, Alyson; Lovett, Ray; Roe, Yvette; Richardson, Alice

    2017-06-05

    Objectives The aim of the study was to assess the utility of national Aboriginal survey data in a regional geospatial analysis of daily smoking prevalence for Aboriginal and Torres Strait Islander Australians and discuss the appropriateness of this analysis for policy and program impact assessment.Methods Data from the last two Australian Bureau of Statistics (ABS) national surveys of Aboriginal and Torres Strait Islander people, the National Aboriginal and Torres Strait Islander Social Survey 2014-15 (n=7022 adults) and the National Aboriginal and Torres Strait Islander Health Survey 2012-13 (n=10896 adults), were used to map the prevalence of smoking by Indigenous regions.Results Daily smoking prevalence in 2014-15 at Indigenous regions ranges from 27.1% (95%CI 18.9-35.3) in the Toowoomba region in Queensland to 68.0% (95%CI 58.1-77.9) in the Katherine region in the Northern Territory. The confidence intervals are wide and there is no significant difference in daily smoking prevalence between the two time periods for any region.Conclusion There are significant limitations with analysing national survey data at finer geographical scales. Given the national program for Indigenous tobacco control is a regional model, evaluation requires finer geographical analysis of smoking prevalence to inform public health progress, policy and program effects. Options to improve the data currently collected include increasing national survey sample sizes, implementing a smoking status question in census surveys, investing in current cohort studies focused on this population or implementing localised surveys.What is known about the topic? The last geospatial analysis of Aboriginal and Torres Strait Islander smoking prevalence was undertaken in 1997. Current national survey data have not been analysed geospatially.What does this paper add? This paper provides new insights into the use of national survey data for understanding regional patterns and prevalence levels of smoking in

  10. Strategic approaches to enhanced health service delivery for Aboriginal and Torres Strait Islander people with chronic illness: a qualitative study

    Directory of Open Access Journals (Sweden)

    Aspin Clive

    2012-06-01

    Full Text Available Abstract Background Aboriginal and Torres Strait Islander people with chronic illness confront multiple challenges that contribute to their poor health outcomes, and to the health disparities that exist in Australian society. This study aimed to identify barriers and facilitators to care and support for Aboriginal and Torres Strait Islander people with chronic illness. Methods Face-to-face in-depth interviews were conducted with Aboriginal and Torres Strait Islander people with diabetes, chronic heart failure or chronic obstructive pulmonary disease (n-16 and family carers (n = 3. Interviews were transcribed verbatim and the transcripts were analysed using content analysis. Recurrent themes were identified and these were used to inform the key findings of the study. Results Participants reported both negative and positive influences that affected their health and well-being. Among the negative influences, they identified poor access to culturally appropriate health services, dislocation from cultural support systems, exposure to racism, poor communication with health care professionals and economic hardship. As a counter to these, participants pointed to cultural and traditional knowledge as well as insights from their own experiences. Participants said that while they often felt overwhelmed and confused by the burden of chronic illness, they drew strength from being part of an Aboriginal community, having regular and ongoing access to primary health care, and being well-connected to a supportive family network. Within this context, elders played an important role in increasing people’s awareness of the impact of chronic illness on people and communities. Conclusions Our study indicated that non-Indigenous health services struggled to meet the needs of Aboriginal and Torres Strait Islander people with chronic illness. To address their complex needs, health services could gain considerably by recognising that Aboriginal and Torres Strait

  11. Sedimentary constraints on the development of a narrow deep strait (São Sebastião Channel, SE Brazil)

    Science.gov (United States)

    Alcántara-Carrió, Javier; Sasaki, Dalton Kei; Mahiques, Michel Michaelovitch de; Taborda, Rui; de Souza, Luiz Antonio Pereira

    2017-10-01

    The São Sebastião Channel (SSC), which separates São Sebastião Island from the continent, is a deep elongated strait on the inner shelf of the São Paulo Bight (SE Brazil). The aim of this study is to explain why it is presently sediment starved, instead of forming a tombolo. Wave data were obtained from both a WW3 model database and buoy records, and wave propagation patterns from the SWAN numerical model. Grain size trend analysis of 579 surficial sediment samples from the strait and the surrounding region served to estimate the residual transport directions. Bedload sediment transport was computed considering in situ currents and bottom sediment grain size. Moreover, six seismic profiles and one gravity core were obtained in the strait in order to evaluate the hickness of the sedimentary deposits. The geometry of the SSC (X/B=0.3, where B is the breakwater or island diameter and X is its cross-shore distance to the mainland) predicts that a tombolo should be formed, and wave patterns confirm that it is a zone sheltered from both S and NE waves. Previous studies have shown that the hydrodynamics of the SSC is controlled by wind-driven currents, which are more intense in the eastern and central sectors of the strait. The western sector is currently covered by sandy mud, whereas very coarse to fine sand prevails in the deeper eastern sector. Sediment patterns show a trend to deposition of fine sediment in the western sector of the SSC and two main depocentres located at the northern limit of the study area and at the southern mouth of the strait. Sandy mud in the western sector forms a 40-m-thick deposit close to the outer limit of Araçá Bay, whereas the remainder of the SSC is covered by a very thin layer of sandy sediments. Dominance of mud in the depositional western sector suggests low availability of sand in the area. Therefore, despite the geometry and wave patterns of the SSC favouring the formation of a tombolo, the dominance of wind-driven currents

  12. International law of the sea and national legislation on piracy and terrorism in the straits of Malacca: a study in law and policy

    OpenAIRE

    Ja'afar, Sabirin Bin

    2007-01-01

    The issue of piracy and maritime terrorism becomes complicated when it is discussed in relation to the rights of the coastal states regarding the right of passage in straits used for international navigation. One of the issues in this respect is the conflicting interests of littoral states that insist on sovereignty over the sea areas adjacent to their coast and the needs of user states to retain and indeed to have more freedom in navigation while passing through and overflying these straits....

  13. Validation of risk assessment scales and predictors of intentions to quit smoking in Australian Aboriginal and Torres Strait Islander peoples: a cross-sectional survey protocol

    OpenAIRE

    Gould, Gillian Sandra; Watt, Kerrianne; McEwen, Andy; Cadet-James, Yvonne; Clough, Alan R

    2014-01-01

    Introduction Tobacco smoking is a very significant behavioural risk factor for the health of Australian Aboriginal and Torres Strait Islanders, and is embedded as a social norm. With a focus on women of childbearing age, and men of similar age, this project aims to determine how Aboriginal and Torres Strait Islander smokers assess smoking risks and how these assessments contribute to their intentions to quit. The findings from this pragmatic study should contribute to developing culturally ta...

  14. Social determinants and psychological distress among Aboriginal and Torres Strait islander adults in the Australian state of Victoria: a cross-sectional population based study.

    Science.gov (United States)

    Markwick, Alison; Ansari, Zahid; Sullivan, Mary; McNeil, John

    2015-03-01

    Aboriginal and Torres Strait Islander adults in the Australian state of Victoria have a higher prevalence of psychological distress than their non-Aboriginal and Torres Strait Islander counterparts. We sought to explain this inequality, focussing on the social determinants of health. We used population-based survey data from the 2008 Victorian Population Health Survey; a cross-sectional landline computer-assisted telephone survey of 34,168 randomly selected adults. We defined psychological distress as a score of 22 or more on the Kessler 10 Psychological Distress scale. We used logistic regression to identify socio-demographic characteristics and social capital indicators that were associated with psychological distress. We then created multivariable models to explore the association between psychological distress and Aboriginal and Torres Strait Islander status that incorporated all significant socioeconomic status (SES) and social capital variables, adjusting for all non-SES socio-demographic characteristics. Aboriginal and Torres Strait Islander Victorians (24.5%) were more than twice as likely than their non-Aboriginal and Torres Strait Islander counterparts (11.3%) to have psychological distress (odds ratio (OR) = 2.56, 95% confidence interval; 1.67-3.93). Controlling for SES, negative perceptions of the residential neighbourhood, lack of social support from family, social and civic distrust, and all non-SES socio-demographic variables (age, sex, marital status, household composition, and rurality), rendered the previously statistically significant inequality in the prevalence of psychological distress, between Aboriginal and Torres Strait Islander Victorians and their non-Aboriginal and Torres Strait Islander counterparts, insignificant at the p = 0.05 level (OR = 1.50; 0.97-2.32). Psychological distress is an important health risk factor for Aboriginal and Torres Strait Islander adults that has yet to be widely acknowledged and addressed. Addressing the

  15. Shared marine waters of British Columbia and Washington: A scientific assessment of current status and future trends in resource abundance and environmental quality in the strait of Juan de Fuca, Strait of Georgia, and Puget Sound

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    The British Columbia/Washington Marine Science Panel was created in 1993 to evaluate the condition of the marine environment in the Strait of Georgia, Strait of Juan de Fuca, and Puget Sound region on both sides of the international boundary. The panel was asked to produce a report on the current condition of, and trends in, the marine waters shared by the province and state. This report describes the principles followed; the region of concern; physical exchange mechanisms in the transboundary region; movements, status, and trends of transboundary biological resource populations; anthropogenic impacts on the ecosystem and humans; ecosystem sensitivity and future scope of anthropogenic impacts; and degree of harm and management priorities.

  16. A Numerical Model of Seawater Volume and Velocity Dynamic for Marine Currents Power Plant in the Bangka Strait, North Sulawesi, Indonesia

    Science.gov (United States)

    Rompas, P. T. D.; Taunaumang, H.; Sangari, F. J.

    2017-03-01

    One of equipment as prime movers in the marine current power plant is turbine. Marine current turbines require a data of marine currents velocity in its design. The objective of this study was to get the velocities distribution of marine currents in the Bangka strait. The method used survey, observation, and measurement in the Bangka strait. The data of seawater density conducted measurement in the Bangka strait. The data of width and depth of the strait collected from the map of Bangka strait and its depth of the sea. Problem solving of the study used a numerical model. The velocities distribution of marine current obtained from a numerical model in the form of numerical program. The results showed that the velocities distribution at seawater column when low and high tide currents which the maximum happened at 0.1 Sv were 0-0.9 and 0-1.0 m/s respectively, while at 0.3 Sv were 0-2.7 and 0-3.0 m/s respectively. The results will be a product in analyzing the potential kinetic energy that used to design profile of the turbines as prime mover for marine currents power plant in the Bangka strait, North Sulawesi, Indonesia.

  17. Role of the Bering Strait on the hysteresis of the ocean conveyor belt circulation and glacial climate stability.

    Science.gov (United States)

    Hu, Aixue; Meehl, Gerald A; Han, Weiqing; Timmermann, Axel; Otto-Bliesner, Bette; Liu, Zhengyu; Washington, Warren M; Large, William; Abe-Ouchi, Ayako; Kimoto, Masahide; Lambeck, Kurt; Wu, Bingyi

    2012-04-24

    Abrupt climate transitions, known as Dansgaard-Oeschger and Heinrich events, occurred frequently during the last glacial period, specifically from 80-11 thousand years before present, but were nearly absent during interglacial periods and the early stages of glacial periods, when major ice-sheets were still forming. Here we show, with a fully coupled state-of-the-art climate model, that closing the Bering Strait and preventing its throughflow between the Pacific and Arctic Oceans during the glacial period can lead to the emergence of stronger hysteresis behavior of the ocean conveyor belt circulation to create conditions that are conducive to triggering abrupt climate transitions. Hence, it is argued that even for greenhouse warming, abrupt climate transitions similar to those in the last glacial time are unlikely to occur as the Bering Strait remains open.

  18. An Experiment to Evaluate Skylab Earth Resources Sensors for Detection of the Gulf Stream. [Straits of Florida

    Science.gov (United States)

    Maul, G. A. (Principal Investigator); Gordon, H. R.; Baig, S. R.; Mccaslin, M.; Devivo, R. J.

    1976-01-01

    The author has identified the following significant results. An experiment to evaluate the Skylab earth resources package for observing ocean currents was performed in the Straits of Florida in January 1974. Data from the S190 photographic facility, S191 spectroradiometer and S192 multispectral scanner, were compared with surface observations. The anticyclonic edge of the Gulf Stream could be identified in the Skylab S190A and B photographs, but the cyclonic edge was obscured by clouds. The aircraft photographs were judged not useful for spectral analysis because vignetting caused the blue/green ratios to be dependent on the position in the photograph. The spectral measurement technique could not identify the anticyclonic front, but mass of Florida Bay water which was in the process of flowing into the Straits could be identified and classified. Monte Carlo simulations of the visible spectrum showed that the aerosol concentration could be estimated and a correction technique was devised.

  19. Study on the seasonal migration of surface suspended sediment in the Taiwan Strait based on remote sensing

    Science.gov (United States)

    Xu, Xiaohui; Chen, Jian; Ye, Xiang

    2015-10-01

    Concentration of suspended sediment directly affects the optical properties such as transparency and water color, and aquatic environment as well. This paper selects the Taiwan Strait as study area, establishes inversion mode of suspended sediment by coupling field data with remote sensing reflectance from MODIS data. Monthly-averaged concentrations and seasonal changes of suspended sediment from 2003 to 2012 were calculated and analyzed by the mode. The main results are as follows:(1) remote sensing reflectance at 555nm from MODIS data has high relativity with the field observed turbidity by regression equation of Y =0.8931e123.93x in which Y is TSM concentration, X is Rrs555 and R2 is 0.6836. (2)Suspended sediment in the Taiwan Strait has obviously spatial and temporal distribution characteristics, that higher concentration of suspended sediment is in coastal water and decreases from shore to sea, and highest concentration happens in winter.

  20. Distribution of Synechococcus sp. and Synechococcus bacillaris in the waters of the Straits of Magellan (April 1995-early austral autumn).

    Science.gov (United States)

    Caruso, G; Zaccone, R

    1998-10-01

    During the last oceanographic cruise carried out in the Straits of Magellan (April 1995), a serological approach was used in order to determine the distribution and composition of the picophytoplankton community with respect to two cyanobacteria species, Synechococcus sp. and bacillaris, characterized respectively by phycoerythrin and phycocyanin as the main accessory photosynthetic pigment. In the period examined, the Straits were characterized by generally low concentrations of total picophytoplankton (10(5)-10(6) cells/l). The qualitative composition of the community showed the prevalence of the species Synechococcus sp. in the Pacific basin, whereas S. bacillaris appears to be predominant in the central area. The immunofluorescence method proved to be effective in the study of the diversity of these microorganisms in aquatic environments.

  1. Early westward flow across the Tasman Gateway

    NARCIS (Netherlands)

    Sijp, Willem P.; von der Heydt, A.S.; Bijl, P.K.

    2015-01-01

    The timing and role in ocean circulation and climate of the opening of Southern Ocean gateways is as yet elusive. Recent micropaleontological studies suggest the onset of throughflow of surface waters from the SW Pacific into the Australo-Antarctic Gulf through a southern shallow opening of the Tasm

  2. Gas futurists look westward off Libya

    Energy Technology Data Exchange (ETDEWEB)

    Snieckus, D.

    2003-06-01

    This article reports on the Western Libyan two-field Gas Project now underway to pass gas from the desert Wafa field and the offshore Bahr Essalam field in the Gulf of Gabes to the Mellitah onshore complex for final processing before transport via the long distance trunk line - the GreenStream - across the Mediterranean to Sicily. Details are given of the design, fabrication and installation of the Sabratha wellhead and production platform which will treat the sour gas, and the daisy chain linking the Sabrathe platform with the offshore Bahr Essalam subsea development. The selection of materials for the piping and components, the project timescales, and the planned route for the GreenStream are discussed.

  3. STARE velocities: 2. Evening westward electron flow

    Directory of Open Access Journals (Sweden)

    M. Uspensky

    2004-04-01

    Full Text Available Four evening events and one morning event of joint EISCAT/STARE observations during ~22h are considered and the differences between observed STARE line-of-sight (l-o-s velocities and EISCAT electron drift velocities projected onto the STARE beams are studied. We demonstrate that the double-pulse technique, which is currently in use in the STARE routine data handling, typically underestimates the true phase velocity as inferred from the multi-pulse STARE data. We show that the STARE velocities are persistently smaller (1.5–2 times than the EISCAT velocities, even for the multi-pulse data. The effect seems to be more pronounced in the evening sector when the Finland radar observes at large flow angles. We evaluate the performance of the ion-acoustic approach (IAA, Nielsen and Schlegel, 1985 and the off-orthogonal fluid approach (OOFA, Uspensky et al., 2003 techniques to predict the true electron drift velocity for the base event of 12 February 1999. The IAA technique predicts the convection reasonably well for enhanced flows of >~1000m/s, but not so well for slower ones. By considering the EISCAT N(h profiles, we derive the effective aspect angle and effective altitude of backscatter, and use this information for application of the OOFA technique. We demonstrate that the OOFA predictions for the base event are superior over the IAA predictions and thus, we confirm that OOFA predicts the electron velocities reasonably well in the evening sector, in addition to the morning sector, as concluded by Uspensky et al. (2003. To check how "robust" the OOFA model is and how successful it is for convection estimates without the EISCAT support, we analysed three additional evening events and one additional morning event for which information on N(h profiles was intentionally ignored. By accepting the mean STARE/EISCAT velocity ratio of 0.55 and the mean azimuth rotation of 9° (derived for the basic event, we show that the OOFA performs reasonably well for these additional events.

    Key words. Ionosphere (ionospheric irregularities, plasma waves and instabilities, auroral ionosphere

  4. Coexisting methane and oxygen excesses in nitrate-limited polar water (Fram Strait during ongoing sea ice melting

    Directory of Open Access Journals (Sweden)

    E. Damm

    2011-05-01

    Full Text Available Summer sea ice cover in the Arctic Ocean has undergone a reduction in the last decade exposing the sea surface to unforeseen environmental changes. Melting sea ice increases water stratification and induces nutrient limitation, which is also known to play a crucial role in methane formation in oxygenated surface water. We report on a hotspot of methane formation in the marginal ice zone in the western Fram Strait. Our study is based on measurements of oxygen, methane, DMSP, nitrate and phosphate concentrations as well as on phytoplankton composition and light transmission, conducted along the 79° N oceanographic transect. We show that between the eastern Fram Strait, where Atlantic water enters from the south and the western Fram Strait, where Polar water enters from the north, different nutrient limitation occurs and consequently different bloom conditions were established. Ongoing sea ice melting enhances the environmental differences and initiates regenerated production in the western Fram Strait. In a unique biogeochemical feedback process, methane production occurs despite an oxygen excess. We postulate that DMSP (dimethylsulfoniopropionate released from sea ice may serve as a precursor for methane formation. Thus, feedback effects on cycling pathways of methane are likely, with DMSP catabolism in high latitudes possibly contributing to a warming effect on the earth's climate. This process could constitute an additional component in biogeochemical cycling in a seasonal ice-free Arctic Ocean. The metabolic activity (respiration of unicellular organisms explains the presence of anaerobic conditions in the cellular environment. Therefore we present a theoretical model which explains the maintenance of anaerobic conditions for methane formation inside bacterial cells, despite enhanced oxygen concentrations in the environment.

  5. Coexisting methane and oxygen excesses in nitrate-limited polar water (Fram Strait) during ongoing sea ice melting

    Science.gov (United States)

    Damm, E.; Thoms, S.; Kattner, G.; Beszczynska-Möller, A.; Nöthig, E. M.; Stimac, I.

    2011-05-01

    Summer sea ice cover in the Arctic Ocean has undergone a reduction in the last decade exposing the sea surface to unforeseen environmental changes. Melting sea ice increases water stratification and induces nutrient limitation, which is also known to play a crucial role in methane formation in oxygenated surface water. We report on a hotspot of methane formation in the marginal ice zone in the western Fram Strait. Our study is based on measurements of oxygen, methane, DMSP, nitrate and phosphate concentrations as well as on phytoplankton composition and light transmission, conducted along the 79° N oceanographic transect. We show that between the eastern Fram Strait, where Atlantic water enters from the south and the western Fram Strait, where Polar water enters from the north, different nutrient limitation occurs and consequently different bloom conditions were established. Ongoing sea ice melting enhances the environmental differences and initiates regenerated production in the western Fram Strait. In a unique biogeochemical feedback process, methane production occurs despite an oxygen excess. We postulate that DMSP (dimethylsulfoniopropionate) released from sea ice may serve as a precursor for methane formation. Thus, feedback effects on cycling pathways of methane are likely, with DMSP catabolism in high latitudes possibly contributing to a warming effect on the earth's climate. This process could constitute an additional component in biogeochemical cycling in a seasonal ice-free Arctic Ocean. The metabolic activity (respiration) of unicellular organisms explains the presence of anaerobic conditions in the cellular environment. Therefore we present a theoretical model which explains the maintenance of anaerobic conditions for methane formation inside bacterial cells, despite enhanced oxygen concentrations in the environment.

  6. PCDD and PCDF exposures among fishing community through intake of fish and shellfish from the Straits of Malacca

    OpenAIRE

    Azlan, Azrina; Mohamad Nasir, Nurul Nadiah; Shamsudin, Norashikin; Rahman, Hejar Abdul; Khoo, Hock Eng; Razman, Muhammad Rizal

    2015-01-01

    Background Exposure to PCDD/PCDF (dioxin and furan) through consumption of fish and shellfish is closely related to the occurrence of skin diseases, such as chloracne and hyperpigmentation. This study aimed to determine the exposure of PCDD/PCDF and its congeners in fish and shellfish obtained from different regions of the Straits of Malacca among the fishing community. Methods The risk of fish and shellfish consumption and exposure to PCDD/PCDF among fishermen living in coastal areas of the ...

  7. Providing culturally appropriate mental health first aid to an Aboriginal or Torres Strait Islander adolescent: development of expert consensus guidelines

    OpenAIRE

    Chalmers, Kathryn J.; Bond, Kathy S.; Jorm, Anthony F; Kelly, Claire M; Kitchener, Betty A; Williams-Tchen, AJ

    2014-01-01

    Background It is estimated that the prevalence of mental illness is higher in Aboriginal and Torres Strait Islander adolescents compared to non-Aboriginal adolescents. Despite this, only a small proportion of Aboriginal youth have contact with mental health services, possibly due to factors such as remoteness, language barriers, affordability and cultural sensitivity issues. This research aimed to develop culturally appropriate guidelines for anyone who is providing first aid to an Australian...

  8. Vertical and horizontal fluxes of plutonium and americium in the western Mediterranean and the Strait of Gibraltar.

    Science.gov (United States)

    León Vintró, L; Mitchell, P I; Condren, O M; Downes, A B; Papucci, C; Delfanti, R

    1999-09-30

    New data on the vertical distributions of plutonium and americium in the waters of the western Mediterranean and the Strait of Gibraltar are examined in terms of the processes governing their delivery to, transport in and removal from the water column within the basin. Residence times for plutonium and americium in surface waters of approximately 15 and approximately 3 years, respectively, are deduced, and it is shown that by the mid 1990s only approximately 35% of the 239,240Pu and approximately 5% of the 241Am deposited as weapons fallout still resided in the water column. Present 239,240Pu inventories in the water column and the underlying sediments are estimated to be approximately 25 TBq and approximately 40 TBq, respectively, which reconcile well with the time-integrated fallout deposition in this zone, taken to be approximately 69 TBq. The data show that there are significant net outward fluxes of plutonium and americium from the basin through the Strait of Gibraltar at the present time. These appear to be compensated by net inward fluxes of similar magnitude through the Strait of Sicily. Thus, the time-integrated fallout deposition in the western basin can be accounted for satisfactorily in terms of present water column and sediment inventories. Enhanced scavenging on the continental shelves, as evidenced by the appreciably higher transuranic concentrations in shelf sediments, supports this contention.

  9. Lateral supply and downward export of particulate matter from upper waters to the seafloor in the deep eastern Fram Strait

    Science.gov (United States)

    Lalande, Catherine; Nöthig, Eva-Maria; Bauerfeind, Eduard; Hardge, Kristin; Beszczynska-Möller, Agnieszka; Fahl, Kirsten

    2016-08-01

    Time-series sediment traps were deployed at 4 depths in the eastern Fram Strait from July 2007 to June 2008 to investigate variations in the magnitude and composition of the sinking particulate matter from upper waters to the seafloor. Sediment traps were deployed at 196 m in the Atlantic Water layer, at 1296 and 2364 m in the intermediate and deep waters, and at 2430 m on a benthic lander in the near-bottom layer. Fluxes of total particulate matter, particulate organic carbon, particulate organic nitrogen, biogenic matter, lithogenic matter, biogenic particulate silica, calcium carbonate, dominant phytoplankton cells, and zooplankton fecal pellets increased with depth, indicating the importance of lateral advection on fluxes in the deep Fram Strait. The lateral supply of particulate matter was further supported by the constant fluxes of biomarkers such as brassicasterol, alkenones, campesterol, β-sitosterol, and IP25 at all depths sampled. However, enhanced fluxes of diatoms and appendicularian fecal pellets from the upper waters to the seafloor in the presence of ice during spring indicated the rapid export (15-35 days) of locally-produced large particles that likely contributed most of the food supply to the benthic communities. These results show that lateral supply and downward fluxes are both important processes influencing the transport of particulate matter to the seafloor in the deep eastern Fram Strait, and that particulate matter size dictates the prevailing sinking process.

  10. The ideas of Frantz Fanon and culturally safe practices for aboriginal and Torres Strait Islander people in Australia.

    Science.gov (United States)

    Molloy, Luke; Grootjans, John

    2014-03-01

    Mainstream mental health services in Australia have failed to provide culturally appropriate care for Aboriginal and Torres Strait Islander people despite several national reports and policies that have attempted to promote positive service development in response to the calls for change from the Aboriginal and Torres Strait Islander communities. In light of this situation, this article considers the ideas of Frantz Fanon and their potential for promoting cultural safety (Ramsden, 2002) in mainstream mental health services. This article argues that Fanon's ideas provide a conceptual strategy for nurses that prompts reflection and establishes a critical theoretical perspective linking power imbalance and inequitable social relationships in health care, thus complementing the aims of cultural safety. The purpose of this critical reflection is to guide nurses' understanding of the relationship between colonization and health status in order to change their attitudes from those that continue to support current hegemonic practices and systems of health care to those that support the health of Aboriginal and Torres Strait Islander people.

  11. The Gulf of Carpentaria heated Torres Strait and the Northern Great Barrier Reef during the 2016 mass coral bleaching event

    Science.gov (United States)

    Wolanski, E.; Andutta, F.; Deleersnijder, E.; Li, Y.; Thomas, C. J.

    2017-07-01

    The 2015/16 ENSO event increased the temperature of waters surrounding northeast Australia to above 30 °C, with large patches of water reaching 32 °C, for over two months, which led to severe bleaching of corals of the Northern Great Barrier Reef (NGBR). This study provides evidence gained from remote-sensing data, oceanographic data and oceanographic modeling, that three factors caused this excessive heating, namely: 1) the shutdown of the North Queensland Coastal Current, which would otherwise have flushed and cooled the Northern Coral Sea and the NGBR through tidal mixing 2) the advection of warm (>30 °C) water from the Gulf of Carpentaria eastward through Torres Strait and then southward over the NGBR continental shelf, and 3) presumably local solar heating. The eastward flux of this warm water through Torres Strait was driven by a mean sea level difference on either side of the strait that in turn was controlled by the wind, which also generated the southward advection of this warm water onto the NGBR shelf. On the NGBR shelf, the residence time of this warm water was longer inshore than offshore, and this may explain the observed cross-shelf gradient of coral bleaching intensity. The fate of the Great Barrier Reef is thus controlled by the oceanography of surrounding seas.

  12. The origin, historical variations, and distribution of heavy metals in the Qiongzhou Strait and nearby marine areas

    Science.gov (United States)

    Zhang, Zhiqiang; Chen, Liang; Wang, Weiping; Li, Tuanjie; Zu, Tingting

    2017-04-01

    We analyzed heavy metal concentrations in a number of surface sediments and cores from the Qiongzhou Strait and surrounding marine areas. The areas of high concentrations are primarily outside the eastern mouth of the Qiongzhou Strait and on the west side of the Leizhou Peninsula, whereas the areas of low concentrations are located primarily in the eastern Qiongzhou Strait. The maximum Cd, Pb and Zn concentrations in the samples collected in our study do not exceed the official standards for marine sediments, whereas the concentrations of Cr and Cu slightly exceed the standards. Correlations exist between the concentrations of Cu, Pb, Zn, Cr and Cd, and the concentrations of these metals are positively correlated with the mean particle size (φ value), indicating that the finer sediments have adsorbed greater amounts of heavy metal elements than the coarser sediments. An evaluation of the potential environmental risks demonstrates that certain indices of heavy metal pollution and environmental risks are relatively low and may be assigned low risk levels, thereby indicating that, in terms of heavy metals, the marine sedimentary environment in this region is only mildly impacted. Our analysis of the contaminant origins shows that the heavy metals in this region primarily originate in the Pearl River Estuary and that a small amount of them is derived from local runoff. The elevated heavy metal concentrations from the upper sections of the cores started 130 years ago, which indicats that heavy metals in the surface sediments are primarily due to human activities associated with industrialization.

  13. Spatial and temporal variation of soft-bottom peracarid (Crustacea: Peracarida infauna in the Canakkale Strait (Turkey

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    H. ASLAN-CIHANGIR

    2012-12-01

    Full Text Available The biodiversity and distribution of soft-bottom peracarid crustaceans were analyzed in the south part of Canakkale Strait, a very important biological corridor between the Mediterranean and the Black Sea. Samples were collected seasonally from 11 coastal stations at depths ranging from 10 to 22 m. Moreover, qualitative samples were collected in summer from 7 stations (40 - 83 m depth located in the middle part of the Strait. A total of 110 species were identified. Amphipods were the dominant group both in terms of species richness and abundance. Apocorophium acutum, Phtisica marina and Microdeutopus versiculatus were the most abundant species. A large number of rare species was recorded, leading to very low similarity values among stations. Six different feeding types were detected, with surface deposit feeders being the dominant one in the area. Significant differences in abundances and assemblage structure were detected along the eastern and western coasts of the Strait that could be attributed to food supply and sediment composition, depending on bottom current velocities. Possible relations of peracarids with the hydrological regime of the area are also discussed.

  14. STRait Razor: a length-based forensic STR allele-calling tool for use with second generation sequencing data.

    Science.gov (United States)

    Warshauer, David H; Lin, David; Hari, Kumar; Jain, Ravi; Davis, Carey; Larue, Bobby; King, Jonathan L; Budowle, Bruce

    2013-07-01

    Recent studies have demonstrated the capability of second generation sequencing (SGS) to provide coverage of short tandem repeats (STRs) found within the human genome. However, there are relatively few bioinformatic software packages capable of detecting these markers in the raw sequence data. The extant STR-calling tools are sophisticated, but are not always applicable to the analysis of the STR loci commonly used in forensic analyses. STRait Razor is a newly developed Perl-based software tool that runs on the Linux/Unix operating system and is designed to detect forensically-relevant STR alleles in FASTQ sequence data, based on allelic length. It is capable of analyzing STR loci with repeat motifs ranging from simple to complex without the need for extensive allelic sequence data. STRait Razor is designed to interpret both single-end and paired-end data and relies on intelligent parallel processing to reduce analysis time. Users are presented with a number of customization options, including variable mismatch detection parameters, as well as the ability to easily allow for the detection of alleles at new loci. In its current state, the software detects alleles for 44 autosomal and Y-chromosome STR loci. The study described herein demonstrates that STRait Razor is capable of detecting STR alleles in data generated by multiple library preparation methods and two Illumina(®) sequencing instruments, with 100% concordance. The data also reveal noteworthy concepts related to the effect of different preparation chemistries and sequencing parameters on the bioinformatic detection of STR alleles.

  15. The fundamental characteristics of current in the Bering Strait and the Chukchi Sea from July to September 2003

    Institute of Scientific and Technical Information of China (English)

    LI Lei; DU Ling; ZHAO Jinping; ZUO Juncheng; LI Peiliang

    2005-01-01

    The characteristics of current in the Bering Strait and the Chukchi Sea are analyzed based on the two current data on the mooring stations during the Second National Arctic Research Expedition of China in 2003. The tidal currents of the principal diurnal and semidiurnal ellipses rotate clockwise in the upper layer, except for N2, S2, and Q1 at Sta. ST. In the Bering Strait (Sta. ST), the major semi-axis of tidal current constituent M2 is 2.9 cm/s in the upper layer, which is much smaller than that of semi-monthly oscillation (11.8 cm/s);and the mean current flows northwestward at the amplitude of about 20 cm/s and varies a little with depth. During the cruise, the current has significant semi-monthly oscillation at the two mooring stations. The spectra analyses of the air pressure gradient and the wind stress show that there are the semi-monthly oscillations in these two data series. The near-inertial current, approximately 4 cm/s, presents almost the same magnitude of the principal tidal currents in the Bering Strait.

  16. Inter-annual variability and long term predictability of exchanges through the Strait of Gibraltar

    Science.gov (United States)

    Boutov, Dmitri; Peliz, Álvaro; Miranda, Pedro M. A.; Soares, Pedro M. M.; Cardoso, Rita M.; Prieto, Laura; Ruiz, Javier; García-Lafuente, Jesus

    2014-03-01

    Inter-annual variability of calculated barotropic (netflow) and simulated baroclinic (inflow and outflow) exchanges through the Strait of Gibraltar is analyzed and their response to the main modes of atmospheric variability is investigated. Time series of the outflow obtained by high resolution simulations and estimated from in-situ Acoustic Doppler Current Profiler (ADCP) current measurements are compared. The time coefficients (TC) of the leading empirical orthogonal function (EOF) modes that describe zonal atmospheric circulation in the vicinity of the Strait (1st and 3rd of Sea-Level Pressure (SLP) and 1st of the wind) show significant covariance with the inflow and outflow. Based on these analyses, a regression model between these SLP TCs and outflow of the Mediterranean Water was developed. This regression outflow time series was compared with estimates based on current meter observations and the predictability and reconstruction of past exchange variability based on atmospheric pressure fields are discussed. The simple regression model seems to reproduce the outflow evolution fairly reasonably, with the exception of the year 2008, which is apparently anomalous without available physical explanation yet. The exchange time series show a reduced inter-annual variability (less than 1%, 2.6% and 3.1% of total 2-day variability, for netflow, inflow and outflow, respectively). From a statistical point of view no clear long-term tendencies were revealed. Anomalously high baroclinic fluxes are reported for the years of 2000-2001 that are coincident with strong impact on the Alboran Sea ecosystem. The origin of the anomalous flow is associated with a strong negative anomaly (~ - 9 hPa) in atmospheric pressure fields settled north of Iberian Peninsula and extending over the central Atlantic, favoring an increased zonal circulation in winter 2000/2001. These low pressure fields forced intense and durable westerly winds in the Gulf of Cadiz-Alboran system. The signal of

  17. Climate signals in Late Holocene sediments from Maxwell Bay and English Strait (South Shetland Islands, Antarctica)

    Science.gov (United States)

    Hass, H. Christian; Schröder, Simon; Kuhn, Gerhard

    2017-04-01

    Climate fluctuations of the past two millennia such as the Little Ice Age and the Medieval Warm Period are reported mainly from the Northern Hemisphere. Evidence from Antarctica is comparably sparse and reveals regional and temporal differences, which are particularly evident at the western and eastern sides of the Antarctic Peninsula. High-resolution coastal-marine sediment cores from the northernmost tip of the West Antarctic Peninsula reveal periods dominated by finer sediments between periods that lack the finer sediment component. In Maxwell Bay this fine sediment (grain size mode around 16 µm) has been traced back to sediment related to the occurrence of glacial meltwater. It was found in sheltered places and meltwater creeks of Potter Cove, a small tributary fjord to Maxwell Bay. In the sediment core this sediment occurs predominantly between 600 and 1250 AD (Medieval Warm Period) whereas it is only sparsely affecting the record between 1450 and 1900 AD (Little Ice Age). The temporal pattern is very similar to global-temperature reconstructions and even resembles temperature reconstructions from the Northern Hemisphere. To avoid local effects that may occur in Maxwell Bay more sediment cores were taken from bays and straits further south of King George Island during Cruise PS97 of RV "Polarstern" in 2016. A core from English Strait reveals completely different sedimentary conditions with no detectable meltwater signal (16 µm). However, the mean grain size record resembles that of the cores from Maxwell Bay. The lack of a clear-cut meltwater sediment class as it occurs further north is likely the result of a much smaller hinterland (Greenwich and Robert islands) when compared to Maxwell Bay between Nelson Island and the much bigger King George Island where glaciers and ice sheets discharge large quantities of very turbid meltwater directly into the bay. It is concluded that during the warmer climate periods a large amount of meltwater was released along the

  18. Dolphin Watching in the Southern Tañon Strait Protected Seascape, Philippines: Issues and Challenges

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    Lemnuel V. Aragones

    2013-12-01

    Full Text Available Dolphin watching is a growing economic activity in the southern Tañon Strait Protected Seascape (TSPS, the Philippines, an area that is also heavily exploited by fisheries. In order to examine the issues and challenges in this growing industry, we monitored relevant information regarding cetacean watching, conducted focus group discussions (FGDs and educational seminar-workshops for various local stakeholders from 2004 to 2006, and followed these up from 2008-2012. From 9 May to 16 August 2004, we conducted structured interviews to determine the perceptions of cetacean-watching tourists (CWTs and assess the level of local knowledge of f ishers and non-fishers (NFs regarding marine mammals and environmental management in this area. Ninety f ive (95 CWTs, 100 local fishers, and 64 NFs were interviewed. Sixty seven percent (n=64 of the CWTs believed that the overall quality of tours was impressive primarily because they were able to watch, at reasonable costs, large groups of dolphins in close proximity and in an almost pristine environment. The majority of CWTs (~91% felt that there is a need to develop a ‘Special Management Plan’ (SMP for the southern TSPS focusing on cetaceans and their habitats. The increasing number of dolphin watching boats, heavy exploitation of f ishing ground, misperception of local f ishers that cetaceans are competitors with f isheries, and lack of a SMP or a Management Plan per se for TSPS warranted the facilitation of a participatory management process to protect the cetaceans and their habitats.This study has shown that even with only preliminary results, survey interviews of key stakeholders in combination with FGDs and seminar-workshop could be critical in facilitating a participatory management process. In the case of the TSPS, this par ticipatory approach led to the formation of the Tañon Strait Association of Dolphin and Whale Watching Operators, Inc. (TaSADoWWI, and eventual development of cetacean

  19. Using cultural immersion as the platform for teaching Aboriginal and Torres Strait Islander health in an undergraduate medical curriculum.

    Science.gov (United States)

    Smith, Janie D; Wolfe, Christina; Springer, Shannon; Martin, Mary; Togno, John; Bramstedt, Katrina A; Sargeant, Sally; Murphy, Bradley

    2015-01-01

    In 2011 Bond University was looking for innovative ways to meet the professional standards and guidelines in Aboriginal and Torres Strait Islander health in its Bachelor of Medicine, Bachelor of Surgery (MBBS) curriculum. In 2012 Bond piloted a compulsory cultural immersion program for all first year students, which is now a usual part of the MBBS program. Three phases were included - establishing an Indigenous health group, determining the Aboriginal and Torres Strait Islander educational content based on the professional standards and developing nine educational sessions and resources - as well as significant administrative processes. The cultural immersion was piloted in 2012 with 92 first year medical students. Following refinements it was repeated in 2013 with 95 students and in 2014 with 94 students. A comprehensive evaluation process was undertaken that included a paper-based evaluation form using a five-point Likert scale, as well as a confidential talking circle evaluation. The response rate was 95.4% (n=271, pooled cohort). Data were entered separately into SPSS and annual reports were written to the Faculty. Descriptive statistics are reported alongside themed qualitative data. The three combined student evaluation results were extremely positive. Students (n=271) strongly agreed that the workshop was well organised (M=4.3), that the facilitators contributed very positively to their experience (M=4.3), and that they were very satisfied overall with the activity (M=4.2). They agreed that the eight overall objectives had been well met (M=3.9-4.3). The nine sessions were highly evaluated with mean ratings of between 3.9 and 4.8. The 'best thing' about the immersion identified by more than half of the students was overwhelmingly (n=140) the Storytelling session, followed by bonding with the cohort, the Torres Strait Islander session and learning more about culture. The item identified as needing most improvement was the food (n=87), followed by the

  20. Comparison of Chlorophyll-a Measurement Using Multi Spatial Imagery and Numerical Model in Bali Strait

    Science.gov (United States)

    Hanintyo, Rizki; susilo, Eko

    2016-11-01

    One of abundance of nutrient in coastal area is chlorophyll-a, where chlorophyll-a is a driving factor to derive fishing ground location. There's several method has been used to derive chlorophyll-a concentration from insitu data, remote sensing satellite data, and ocean dynamics models, but we are not decide those data for certain area in coastal area and open ocean. In this paper, we will use Aqua-Terra MODIS, Landsat -8 and INDESO Satellite observation dataset to detect chlorophyll-a and also using dynamic modelling produced by INDESO and MyOcean/Marine Copernicus. Using a lot variation of data to understand the differences of spatial resolution and accuracy with observed insitu data. After calculating data comparison with insitu data in bali strait on 2014, we can conclude that Landsat-8 data has the highest r value r=0.41. For model data, comparison between insitu data and MyOcean data has r=0.3. in the other hand, insitu data and INDESO data model has r=0.26. In coastal areas (case 2 water), Landsat-8 data performed to give detail information of chlorophyll-a. Furthermore for open ocean areas (case 1 water), we can use numerical model from MyOcean/Marine Copernicus because it has lower resolution and able to forecast. For those data, it can help non artisanal fisheries to predict chlorophyll-a area in their fishing ground areas

  1. A Pliocene flora and insect fauna from the Bering Strait region

    Science.gov (United States)

    Hopkins, D.M.; Matthews, J.V.; Wolfe, J.A.; Silberman, M.L.

    1971-01-01

    A flood-plain forest has been preserved beneath a lava flow that invaded the Inmachuk River Valley in the northern part of the Seward Peninsula, Alaska, during the Pliocene Epoch. The fossil flora is of great biogeographic interest because of its position (Fig. 1) in a tundra region about 250 km east of Bering Strait, 75 km south of the Arctic Circle, and 65 km west of the northwestern limit of spruce-birch forest. It provides insight into the history of the development of the circumpolar boreal forest (taiga). A rich arthropod fauna casts light on the phylogeny of several modern insect genera and on the origin of modern tundra faunas. A potassium-argon analysis of the overlying basaltic lava provides our first radiometric age estimate (5.7??0.2 million years) for the Clamgulchian Stage, a Late Tertiary time-stratigraphic unit based on fossil plants and widely recognized in Alaska (Wolfe and Hopkins 1967) and northeastern Siberia. ?? 1971.

  2. Lithodynamic processes in the construction area of a bridge across the kerch strait

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    Vvedenskiy Aleksey Rostislavovich

    2016-11-01

    Full Text Available The information about the evolution of the bottom topography in the construction area is necessary in the design and construction of hydraulic structures in sea, as well as information about possible deformations of the bottom caused by both natural reasons and the appearance of new hydraulic objects in the waters. In the given research the authors propose an analysis of lithodynamic processes in the area of the construction of the bridge across the Kerch Strait. Several physico-mathematical models were used for calculation and description of lithodynamic processes in the construction site of the Kerch Bridge. They may be divided into two groups: atmospheric and water. Many important properties of hydrometeorological conditions may be obtained only by modeling. The model WRF is used in the research, which is applied in many foreign and domestic centers for simulation and forecast of regional atmospheric circulation due to its high quality and ease. The main steps of the calculations are provided: beginning with the collection of basic information up to combining the results of numerical experiments on several mathematical models. Special attention is paid to sedimentation and erosion associated with construction of temporary piers and waterways to them.

  3. Active faults and historical earthquakes in the Messina Straits area (Ionian Sea

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    A. Polonia

    2012-07-01

    Full Text Available The Calabrian Arc (CA subduction complex is located at the toe of the Eurasian Plate in the Ionian Sea, where sediments resting on the lower plate have been scraped off and piled up in the accretionary wedge due to the African/Eurasian plate convergence and back arc extension. The CA has been struck repeatedly by destructive historical earthquakes, but knowledge of active faults and source parameters is relatively poor, particularly for seismogenic structures extending offshore. We analysed the fine structure of major tectonic features likely to have been sources of past earthquakes: (i the NNW–SSE trending Malta STEP (Slab Transfer Edge Propagator fault system, representing a lateral tear of the subduction system; (ii the out-of-sequence thrusts (splay faults at the rear of the salt-bearing Messinian accretionary wedge; and (iii the Messina Straits fault system, part of the wide deformation zone separating the western and eastern lobes of the accretionary wedge.

    Our findings have implications for seismic hazard in southern Italy, as we compile an inventory of first order active faults that may have produced past seismic events such as the 1908, 1693 and 1169 earthquakes. These faults are likely to be source regions for future large magnitude events as they are long, deep and bound sectors of the margin characterized by different deformation and coupling rates on the plate interface.

  4. Particle size distributions and organic-inorganic compositions of suspended particulate matters around the Bohai Strait

    Science.gov (United States)

    Wang, Xiao; Bian, Changwei; Bi, Rong; Jiang, Wensheng; Zhang, Hua; Zhang, Xueqing

    2017-02-01

    Laser in situ scattering and transmissometry (LISST) significantly improves our ability to assess particle size distribution (PSD) in seawater, while wide-ranging measurements of the organic-inorganic compositions of suspended particulate matters (SPM) are still difficult by using traditional methods such as microscopy. In this study, PSD properties and SPM compositions around the Bohai Strait (China) were investigated based on the measurements by LISST in combination with hydro-biological parameters collected from a field survey in summer 2014. Four typical PSD shapes were found in the region, namely right-peak, left-peak, double-peak and negative-skew shapes. The double-peak and negative-skew shapes may interconvert into each other along with strong hydrodynamic variation. In the upper layer of the Bohai Sea, organic particles were in the majority, with inorganic particles rarely observed. In the bottom layer, SPM were the mixture of organic and inorganic matters. LISST provided valuable baseline information on size-resolved organic-inorganic compositions of SPM: the size of organic particles mainly ranged from 4 to 20 μm and 40 to 100 μm, while most SPM ranging from 20 to 40 μm were composed of inorganic sediment.

  5. Conservation of the Eastern Taiwan Strait Chinese White Dolphin (Sousa chinensis): Fishers' Perspectives and Management Implications

    Science.gov (United States)

    Liu, Ta-Kang; Wang, Yu-Cheng; Chuang, Laurence Zsu-Hsin; Chen, Chih-How

    2016-01-01

    The abundance of the eastern Taiwan Strait (ETS) population of the Chinese white dolphin (Sousa chinensis) has been estimated to be less than 100 individuals. It is categorized as critically endangered in the IUCN Red List of Threatened Species. Thus, immediate measures of conservation should be taken to protect it from extinction. Currently, the Taiwanese government plans to designate its habitat as a Major Wildlife Habitat (MWH), a type of marine protected area (MPA) for conservation of wildlife species. Although the designation allows continuing the current exploitation, however, it may cause conflicts among multiple stakeholders with competing interests. The study is to explore the attitude and opinions among the stakeholders in order to better manage the MPA. This study employs a semi-structured interview and a questionnaire survey of local fishers. Results from interviews indicated that the subsistence of fishers remains a major problem. It was found that stakeholders have different perceptions of the fishers’ attitude towards conservation and also thought that the fishery-related law enforcement could be difficult. Quantitative survey showed that fishers are generally positive towards the conservation of the Chinese white dolphin but are less willing to participate in the planning process. Most fishers considered temporary fishing closure as feasible for conservation. The results of this study provide recommendations for future efforts towards the goal of better conservation for this endangered species. PMID:27526102

  6. Biogeographic patterns of bacterial microdiversity in Arctic deep-sea sediments (Hausgarten, Fram Strait

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    Pier Luigi eButtigieg

    2015-01-01

    Full Text Available Marine bacteria colonising deep-sea sediments beneath the Arctic ocean, a rapidly changing ecosystem, have been shown to exhibit significant biogeographic patterns along transects spanning tens of kilometres and across water depths reaching several thousands of metres (Jacob et al., 2013. Jacob et al. adopted what has become a classical view of microbial diversity based on operational taxonomic units clustered at the 97% sequence identity level of the 16S rRNA gene and observed a very large microbial community replacement at the Hausgarten Long-Term Ecological Research station (Eastern Fram Strait. Here, we revisited these data using the oligotyping approach with the aims of obtaining new insights into ecological and biogeographic patterns associated with bacterial microdiversity in marine sediments and of assessing the level of concordance of these insights with previously obtained results. Variation in oligotype dispersal range, relative abundance, co-occurrence, and taxonomic identity were related to environmental parameters such as water depth, biomass, and sedimentary pigment concentration. This study assesses ecological implications of the new microdiversity-based technique using a well-characterised dataset of high relevance for global change biology.

  7. Development of Seismic Demand for Chang-Bin Offshore Wind Farm in Taiwan Strait

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    Yu-Kai Wang

    2016-12-01

    Full Text Available Taiwan is located on the Pacific seismic belt, and the soil conditions of Taiwan’s offshore wind farms are softer than those in Europe. To ensure safety and stability of the offshore wind turbine supporting structures, it is important to assess the offshore wind farms seismic forces reasonably. In this paper, the relevant seismic and geological data are obtained for Chang-Bin offshore wind farm in Taiwan Strait, the probabilistic seismic hazard analysis (PSHA is carried out, and the first uniform hazard response spectrum for Chang-Bin offshore wind farm is achieved. Compared with existing design response spectrum in the local regulation, this site-specific seismic hazard analysis has influence on the seismic force considered in the design of supporting structures and therefore affects the cost of the supporting structures. The results show that a site-specific seismic hazard analysis is required for high seismic area. The paper highlights the importance of seismic hazard analysis to assess the offshore wind farms seismic forces. The follow-up recommendations and research directions are given for Taiwan’s offshore wind turbine supporting structures under seismic force considerations.

  8. Radioactivity levels in mussels and sediments of the Golden Horn by the Bosphorus Strait, Marmara Sea.

    Science.gov (United States)

    Kılıç, Önder; Belivermiş, Murat; Gözel, Furkan; Carvalho, Fernando P

    2014-09-15

    The Golden Horn is an estuary located in the center of İstanbul receiving freshwater discharges from two creeks and connecting to the Bosphorus Strait. Activity concentrations of natural and artificial radionuclides were determined in mussels (Mytilus galloprovincialis) and sediments from the Golden Horn sampled in February 2012. Mean activity concentrations of (137)Cs, (40)K, (226)Ra, (228)Ra, (210)Po and (210)Pb in the mussels were determined at 1.03±0.23, 389±41.6, 2.61±1.23, not detected (ND), 91.96±37.88 and 11.48±4.85 Bq kg(-1), respectively. In sediments, it was observed that (137)Cs, (40)K, (226)Ra, (228)Ra, (210)Po and (210)Pb activity concentrations inolden Horn were much lower than in mussels from other coastal regions and this was related to low plankton productivity and eutrophication of the Golden Horn. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. High biodiversity on a deep-water reef in the eastern Fram Strait.

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    Kirstin S Meyer

    Full Text Available We report on the distribution and abundance of megafauna on a deep-water rocky reef (1796-2373 m in the Fram Strait, west of Svalbard. Biodiversity and population density are high, with a maximum average of 26.7±0.9 species m(-2 and 418.1±49.6 individuals m(-2 on the east side of the reef summit. These figures contrast with the surrounding abyssal plain fauna, with an average of only 18.1±1.4 species and 29.4±4.3 individuals m(-2 (mean ± standard error. The east side of the reef summit, where the highest richness and density of fauna are found, faces into the predominant bottom current, which likely increases in speed to the summit and serves as a source of particulate food for the numerous suspension feeders present there. We conclude that the observed faunal distribution patterns could be the result of hydrodynamic patterns and food availability above and around the reef. To our knowledge, this study is the first to describe the distribution and diversity of benthic fauna on a rocky reef in deep water.

  10. ­­­­Submarine Mass Wasting on Hovgaard Ridge, Fram Strait, European Arctic

    Science.gov (United States)

    Forwick, M.; Laberg, J. S.; Husum, K.; Gales, J. A.

    2015-12-01

    Hovgaard Ridge is an 1800 m high bathymetric high in the Fram Strait, the only deep-water gateway between the Arctic Ocean and the other World's oceans. The slopes of the ridge provide evidence of various types of sediment reworking, including 1) up to 12 km wide single and merged slide scars with maximum ~30 m high headwalls and some secondary escarpments; 2) maximum 3 km wide and 130 m deep slide scars with irregular internal morphology, partly narrowing towards the foot of the slope; 3) up to 130 m deep, 1.5 km wide and maximum 8 km long channels/gullies originating from areas of increasing slope angle at the margins of a plateau on top of the ridge. Most slide scars result presumably from retrogressive failure related to weak layers in contourites or ash. The most likely trigger mechanism is seismicity related to tectonic activity within the nearby mid-ocean fracture zone. Gully/channel formation is suggested to result from cascading water masses and/or from sediment gravity flows originating from failure at the slope break after winnowing on the plateau of the ridge.

  11. Eating disorder features in indigenous Aboriginal and Torres Strait Islander Australian Peoples

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    Hay Phillipa J

    2012-03-01

    Full Text Available Abstract Background Obesity and related cardiovascular and metabolic conditions are well recognized problems for Australian Aboriginal and Torres Strait Islander peoples. However, there is a dearth of research on relevant eating disorders (EDs such as binge eating disorder in these groups. Methods Data were obtained from interviews of 3047 (in 2005 and 3034 (in 2008 adults who were participants in a randomly selected South Australian household survey of individuals' age > 15 years. The interviewed comprised a general health survey in which ED questions were embedded. Data were weighted according to national census results and comprised key features of ED symptoms. Results In 2005 there were 94 (85 weighted First Australian respondents, and in 2008 65 (70 weighted. Controlling for secular differences, in 2005 rates of objective binge eating and levels of weight and shape influence on self-evaluation were significantly higher in indigenous compared to non-indigenous participants, but no significant differences were found in ED features in 2008. Conclusions Whilst results on small numbers must be interpreted with caution, the main finding was consistent over the two samples. For First Australians ED symptoms are at least as frequent as for non-indigenous Australians.

  12. Low-frequency variability of the exchanged flows through the Strait of Gibraltar during CANIGO

    Science.gov (United States)

    Lafuente, Jesús García.; Delgado, Javier; Vargas, Juan Miguel; Vargas, Manuel; Plaza, Francisco; Sarhan, Tarek

    Time series of the exchanged flows through the Strait of Gibraltar at the eastern section have been estimated from current-meter observations taken between October 1995 and May 1998 within the Canary Islands Azores Gibraltar Observations (CANIGO) project. The inflow exhibits a clear annual signal that peaks in late summer simultaneously with a deepening of the interface. The cycle seems to be driven by the seasonal signal of the density contrast between the surface Atlantic water that forms the inflow and the deep Mediterranean water of the outflow. The outflow and the depth of the interface have predominant semiannual signals and a smaller annual one whose phase agrees with that of the density contrast as well. Local wind stress and atmospheric pressure difference between the Atlantic and the Western Mediterranean to less extent have clear semiannual signal, so that the possibility that the semiannual cycle of the outflow and of the depth of the interface are forced by them was analyzed. The composite Froude number in this section is well below the critical value, suggesting submaximal exchange. Therefore, the conditions in the Alboran basin influence the exchange and some evidence that the size and location of the Western Alboran Gyre contribute to the observed signals, both annual and semiannual, is provided.

  13. Chinstrap penguin foraging area associated with a seamount in Bransfield Strait, Antarctica

    Science.gov (United States)

    Kokubun, Nobuo; Lee, Won Young; Kim, Jeong-Hoon; Takahashi, Akinori

    2015-12-01

    Identifying marine features that support high foraging performance of predators is useful to determine areas of ecological importance. This study aimed to identify marine features that are important for foraging of chinstrap penguins (Pygoscelis antarcticus), an abundant upper-trophic level predator in the Antarctic Peninsula region. We investigated the foraging locations of penguins breeding on King George Island using GPS-depth loggers. Tracking data from 18 birds (4232 dives), 11 birds (2095 dives), and 19 birds (3947 dives) were obtained in 2007, 2010, and 2015, respectively. In all three years, penguins frequently visited an area near a seamount (Orca Seamount) in Bransfield Strait. The percentage of dives (27.8% in 2007, 36.1% in 2010, and 19.1% in 2015) and depth wiggles (27.1% in 2007, 37.2% in 2010, and 22.3% in 2015) performed in this area was higher than that expected from the size of the area and distance from the colony (8.4% for 2007, 14.7% for 2010, and 6.3% for 2015). Stomach content analysis showed that the penguins fed mainly on Antarctic krill. These results suggest that the seamount provided a favorable foraging area for breeding chinstrap penguins, with high availability of Antarctic krill, possibly related to local upwelling.

  14. Conservation of the Eastern Taiwan Strait Chinese White Dolphin (Sousa chinensis): Fishers' Perspectives and Management Implications.

    Science.gov (United States)

    Liu, Ta-Kang; Wang, Yu-Cheng; Chuang, Laurence Zsu-Hsin; Chen, Chih-How

    2016-01-01

    The abundance of the eastern Taiwan Strait (ETS) population of the Chinese white dolphin (Sousa chinensis) has been estimated to be less than 100 individuals. It is categorized as critically endangered in the IUCN Red List of Threatened Species. Thus, immediate measures of conservation should be taken to protect it from extinction. Currently, the Taiwanese government plans to designate its habitat as a Major Wildlife Habitat (MWH), a type of marine protected area (MPA) for conservation of wildlife species. Although the designation allows continuing the current exploitation, however, it may cause conflicts among multiple stakeholders with competing interests. The study is to explore the attitude and opinions among the stakeholders in order to better manage the MPA. This study employs a semi-structured interview and a questionnaire survey of local fishers. Results from interviews indicated that the subsistence of fishers remains a major problem. It was found that stakeholders have different perceptions of the fishers' attitude towards conservation and also thought that the fishery-related law enforcement could be difficult. Quantitative survey showed that fishers are generally positive towards the conservation of the Chinese white dolphin but are less willing to participate in the planning process. Most fishers considered temporary fishing closure as feasible for conservation. The results of this study provide recommendations for future efforts towards the goal of better conservation for this endangered species.

  15. Diurnal evolution of the barrier layer and its local feedback in the central Taiwan Strait

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Diurnal evolution of the barrier layer (BL) and its local feedback features in the central Taiwan Strait (119.2oE,24.3oN) during summertime monsoon are investigated using in situ moored observations conducted by the "Yan-Ping 2" research vessel in late June 2005.During the initiation phase,for the non-solar radiation tends to be trapped in the upper mixed layer,whereas the solar radiation can penetrate deeply through the mixed layer approaching the thermocline,most heat is accumulated inside the BL inducing an inverse-thermal layer.Along with heat convergence inside the BL,thermal exchange increases between the BL and the overlaying mixed layer and finally,a prominently warming mixed layer is formed.Moreover,the BL is associated with a buoyancy frequency minimum with mild stability.Further analysis reveals that the BL’s local feedbacks can be divided into two aspects,on one hand,the BL can generate dramatic changes in the local sensible and latent heat fluxes;on the other hand,the sub-halocline and the thermocline serve as two interfaces during the downward transmission of the wind stirring turbulent kinetic energy (TKE) and as a result,most TKE is retarded by the shallow halocline and being trapped above the upper mixed layer,while the residual pierced through the base of the mixed layer is likewise blocked by the thermocline.

  16. Water quality mapping using remote sensing technique in Penang Straits, Malaysia

    Science.gov (United States)

    Lim, H. S.; MatJafri, M. Z.; Abdullah, K.; Alias, A. N.; Mohd. Saleh, N.

    2008-10-01

    The application of remote sensing to assess water quality for coastal and open ocean has escalated recently due to its capability of scanning wide water bodies within a short time period. In this paper, we examined the spatial variability of chlorophyll within Penang straits, Malaysia. Coastal and estuarine ecosystems typically exhibit high temporal and spatial variability in phytoplankton biomass that is often too difficult to characterize with a limited set of in situ shipboard measurements. In this study, we used ALOS satellite imagery acquired on 24 April 2007. An algorithm for retrieval of chlorophyll level was developed for ALOS data. Chlorophyll samples were collected using a small boat simultaneously with the acquisition of the satellite image. The water locations were determined using a handheld Global Positioning System (GPS). And then the digital numbers for each band corresponding to the sea-truth locations were extracted and then converted into radiance values and reflectance values. The reflectance values were used for calibration of the chlorophyll algorithm. For the regression model, the correlation coefficient (R) and the root-mean-square deviation (RMS) were noted. The proposed algorithm is considered superior based on the values of the correlation coefficient and root-mean-square The water quality image was generated using the multispectral data set and the proposed calibrated TSS algorithm. This study demonstrates that remote sensing can play an important role in water quality assessment by using high resolution satellite image of ALOS data.

  17. Seasonal patterns in Arctic planktonic metabolism (Fram Strait – Svalbard region

    Directory of Open Access Journals (Sweden)

    R. Vaquer-Sunyer

    2012-06-01

    Full Text Available The metabolism of the Arctic Ocean is marked by extreme pronounced seasonality and spatial heterogeneity associated with light conditions, ice cover, water masses and nutrient availability. Here we report the marine planktonic metabolic rates (Net Community Production, Gross Primary Production and Community Respiration along three different seasons of the year for a total of eight cruises along the western sector of the European Arctic (Fram Strait – Svalbard region in the Arctic Ocean margin: one at the end of 2006 (fall/winter, two in 2007 (early spring and summer, two in 2008 (early spring and summer, one in 2009 (late spring–early summer and one in 2010 (spring. The results show that metabolisms of the western sector of the European Arctic varies throughout the year, depending mostly on the stage of bloom, which is mainly determined by availability of light and nutrients. Here we report metabolic rates for the different periods, including the spring bloom, summer and the dark period, increasing considerably the empirical basis on metabolic rates in the Artic Ocean, and especially in the European Arctic corridor. We also report a rough annual metabolic balance for this area of the Arctic Ocean, resulting in a Net Community Production of 108 g C m−2 yr−1.

  18. Baseline concentrations of trace metals in macroalgae from the Strait of Magellan, Chile.

    Science.gov (United States)

    Astorga-España, Maria Soledad; Calisto-Ulloa, Nancy Cristina; Guerrero, Sandra

    2008-02-01

    Samples of four different species of seaweed were collected monthly between October 2000 and March 2001 from the coast of the Strait of Magellan, Chile to establish baseline levels of trace metals (silver, total mercury, nickel, lead, antimony, vanadium and zinc) and to compare the accumulation capacity among species. The algae included in the study were Adenocystis utricularis (n=15); Enteromorpha sp. (n=11), Mazzaella laminarioides (n=12) and Porphyra columbina (n=6). The concentration range of each metal in microg g(-1) dry weight varied as follows: Ag=ND-0.3, Hg=ND-0.02, Ni=ND-12.6, Pb = ND-11.2, Sb=ND-1.97, V=ND-11.34 and Zn=14.10-79. Results showed that levels of Ag, Hg, Ni, Pb, Sb, V and Zn for all species were similar to those found in other studies for non-contaminated areas with very little influence from anthropogenic activity. Also among the four species studied macroalgae Enteromorpha sp. had the highest capacity for metal accumulation and could therefore be considered as a biomonitor for future studies in the area.

  19. Suicides in Aboriginal and Torres Strait Islander children: analysis of Queensland Suicide Register.

    Science.gov (United States)

    Soole, Rebecca; Kõlves, Kairi; De Leo, Diego

    2014-12-01

    Suicide rates among Indigenous Australian children are higher than for other Australian children. The current study aimed to identify factors associated with Indigenous child suicide when compared to other Australian children. Using the Queensland Suicide Register, suicides in Indigenous children (10-14 years) and other Australian children in the same age band were compared. Between 2000 and 2010, 45 child suicides were recorded: 21 of Indigenous children and 24 of other Australian children. This corresponded to a suicide rate of 10.15 suicides per 100,000 for Indigenous children - 12.63 times higher than the suicide rate for other Australian children (0.80 per 100,000). Hanging was the predominant method used by all children. Indigenous children were significantly more likely to suicide outside the home, to be living outside the parental home at time of death, and be living in remote or very remote areas. Indigenous children were found to consume alcohol more frequently before suicide, compared to other Australian children. Current and past treatments of psychiatric disorders were significantly less common among Indigenous children compared to other Australian children. Western conceptualisation of mental illness may not adequately embody Indigenous people's holistic perspective regarding mental health. Further development of culturally appropriate suicide prevention activities for Aboriginal and Torres Strait Islander children is required. © 2014 Public Health Association of Australia.

  20. Assessment of eco-environmental quality of Western Taiwan Straits Economic Zone.

    Science.gov (United States)

    Ma, He; Shi, Longyu

    2016-05-01

    Regional eco-environmental quality is the key and foundation to the sustainable socio-economic development of a region. Eco-environmental quality assessment can reveal the capacity of sustainable socio-economic development in a region and the degree of coordination between social production and the living environment. As part of a new development strategy for Fujian Province, the Western Taiwan Straits Economic Zone (hereafter referred to as the Economic Zone) provides an important guarantee for the development of China's southeastern coastal area. Based on ecological and remote sensing data on the Economic Zone obtained in 2000, 2005, and 2010, this study investigated county-level administrative regions with a comprehensive index of eco-environmental indicators. An objective weighting method was used to determine the importance of each indicator. This led to the development of an indicator system to assess the eco-environmental quality of the economic zone. ArcGIS software was used to assess the eco-environmental quality of the economic zone based on each indicator. The eco-environmental quality index (EQI) of the county-level administrative regions was calculated. The overall eco-environmental quality of the Economic Zone during the period studied is described and analyzed. The results show that the overall eco-environmental quality of the Economic Zone is satisfactory, but significant intraregional differences still exist. The key to improving the overall eco-environmental quality of this area is to restore vegetation and preserve biodiversity.

  1. Ocean acoustic remote sensing using ambient noise: results from the Florida Straits

    Science.gov (United States)

    Brown, M. G.; Godin, O. A.; Zang, X.; Ball, J. S.; Zabotin, N. A.; Zabotina, L. Y.; Williams, N. J.

    2016-07-01

    Noise interferometry is the process by which approximations to acoustic Green's functions, which describe sound propagation between two locations, are estimated by cross-correlating time series of ambient noise measured at those locations. Noise-interferometry-based approximations to Green's functions can be used as the basis for a variety of inversion algorithms, thereby providing a purely passive alternative to active-source ocean acoustic remote sensing. In this paper we give an overview of results from noise interferometry experiments conducted in the Florida Straits at 100 m depth in December 2012, and at 600 m depth in September/October 2013. Under good conditions for noise interferometry, estimates of cross-correlation functions are shown to allow one to perform advanced phase-coherent signal processing techniques to perform waveform inversions, estimate currents by exploiting non-reciprocity, perform time-reversal/back-propagation calculations and investigate modal dispersion using time-warping techniques. Conditions which are favourable for noise interferometry are identified and discussed.

  2. Identification decomposition of regional economic disparity for the west coast of Taiwan Strait of China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Regional economic disparity is a hot issue in the development of society and economy.As the conjunct of the Yangtze River Delta and the Pearl River Delta and the frontier to Taiwan,the west coast of the Taiwan Strait (WCS) is of great social and political significance.The paper defines" the connotation of the WCS,decomposed the regional economic disparity by using weighted coefficient of variation and Theil coeJficient,and explores the industrial and regional source of the regional economic disparity of the WCS.The analysis results show that:(1) the WCS has important political,economic and military position,so it's better to regard it to be comprehensive region,not just refer to Fujian Province;(2)from the industrial decomposition of weighted variation coefficient,the influence of the primary industry was tiny,conversely,the development inequity of the secondary and the tertiary indus'try was the main source of regional economic disparity.Their contribution has had the converse trend and the secondary contribution has gone beyond the tertiary since 2003;(3)from the regional decomposition of Theil coefficient,the regional economic disparity mainly came from inter-area inequity of 4 areas.Moreover,the inner economic disparity mainly drove by Fujian,suggesting that the urban development inequity in Fujian Province was comparatively outstanding.

  3. Numerical simulation of the Kuroshio intrusion into the South China Sea by a passive tracer

    Institute of Scientific and Technical Information of China (English)

    LIU Tongya; XU Jiexin; HE Yinghui; L Haibin; YAO Yuan; CAI Shuqun

    2016-01-01

    Owing to lack of observational data and accurate definition, it is difficult to distinguish the Kuroshio intrusion water from the Pacific Ocean into the South China Sea (SCS). By using a passive tracer to identify the Kuroshio water based on an observation-validated three-dimensional numerical model MITgcm, the spatio-temporal variation of the Kuroshio intrusion water into the SCS has been investigated. Our result shows the Kuroshio intrusion is of distinct seasonal variation in both horizontal and vertical directions. In winter, the intruding Kuroshio water reaches the farthest, almost occupying the area from 18°N to 23°N and 114°E to 121°E, with a small branch flowing towards the Taiwan Strait. The intrusion region of the Kuroshio water decreases with depth gradually. However, in summer, the Kuroshio water is confined to the east of 118°E without any branch reaching the Taiwan Strait; meanwhile the intrusion region of the Kuroshio water increases from the surface to the depth about 205 m, then it decreases with depth. The estimated annual mean of Kuroshio Intrusion Transport (KIT) via the Luzon Strait is westward to the SCS in an amount of –3.86×106 m3/s, which is larger than the annual mean of Luzon Strait Transport (LST) of –3.15×106 m3/s. The KIT above 250 m accounts for 60%–80% of the LST throughout the entire water column. By analyzing interannual variation of the Kuroshio intrusion from the year 2003 to 2012, we find that the Kuroshio branch flowing into the Taiwan Strait is the weaker in winter of La Niña years than those in El Niño and normal years, which may be attributed to the wind stress curl off the southeast China then. Furthermore, the KIT correlates the Niño 3.4 index from 2003 to 2012 with a correlation coefficient of 0.41, which is lower than that of the LST with the Niño 3.4 index, i.e., 0.78.

  4. Geochemical mapping of polluted soils and environmental risk assessment associated to mining activities: a comparison case study in El Campillo (Huelva, Spain) and the Zambales (Luzon Island,The Philippines)

    Science.gov (United States)

    Zuluaga, Maria Clara; Albanese, Stefano; de Vivo, Benedetto; Nieto, Jose Miguel; David, Carlos Primo C.; Norini, Gianluca

    2014-05-01

    The soil is one of the environmental systems which could be most affected by the dispersion of pollutant, also because of the close relationship with the atmosphere and meteoric waters. The distribution and type of contamination depends closely on the climate, precipitations, drainage, vegetation, lithology and human activities. As a matter of fact, soil contamination due to heavy metals and metalloids, such as As, Cd, Cr, Cu, Ni, Pb and Zn, represents the source of a severe potential hazard for the ecosystem equilibrium and the health of living beings. This study is carried out in two abandoned mining zones near to populated areas, which underwent similar mining history, but in very different climatic and environmental conditions. The aim of the research is to analyze the influence of precipitation amounts, soil thickness, drainage density and vegetation cover on pollutant distribution. The first zone is in El Campillo, a town at the Rio Tinto mining district and belongs to the Iberic Pyritic Belt of the southwest Iberian peninsula. This mining site is characterized by a Mediterranean climate with low precipitation (700 mm/year), low vegetation cover and poor soil development. The second case study is the Zambales Mountain Range, a mining district in the Luzon Island of the Philippines dominated by a tropical weather, forests, intense rainfalls (2350 mm/year) and good soil development. The wide spectrum of climatic variables in the case studies requires to develop a single flexible methodology for the mapping and monitoring of the environmental degradation in both semi-arid and tropical environments, allowing comparative studies. The methodological approach comprises remote sensing, Geographic Information System (GIS), spatial statistical analysis, field sampling, ICP analysis and isotopic geochemical analysis. The presentation illustrates the first stage of the project. The processing of multispectral (Aster) and hyperspectral (Hyperion) images, in comparison

  5. Crustal structure of seismic velocity in southern Tibet and east-westward escape of the crustal material--An example by wide-angle seismic profile from Peigu Tso to Pumoyong Tso

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Zhongjie; TENG; Jiwen; LI; Yingkang; S.Klemperer

    2004-01-01

    The reflecting events from Moho and other interfaces within the crust are recognized from the wavefield characteristics of P- and S-wave for the 480km long wide-angle seismic profile between Peigu Tso and Pumoyong Tso. Then, seismic crustal structures of P- and S-wave velocities and Poisson ratio under the nearly east-west profile in southern Tibet are interpreted by fitting the observed traveltimes with the calculated ones by forward modelling. Our interpreting results demonstrate that the crustal thickness varies remarkably in the east-west direction, showing a pattern that the crust could be divided into three parts bounded by the west of Dingri and the east of Dinggyê, respectively, where the depth of Moho is about 71km for the western part, about 76km for the middle and about 74km for the eastern. There is one lower velocity layer (LVL) at the bottom of the upper crust with depth of 20-30 km. One of the distinct features is that the thickness of LVL abruptly thins from 24km on the west to 6km on the east. The other is that the velocity variation in the crust along east-west direction for both P- and S-wave displays a feature as quasi-periodic variation. The lower velocity (compared to the average value for the continent of the globe) in the lower crust and three sets of north-southward active normal faults are probably attributed to the coupling process of material delamination in the lower crust, crustal thicking and east-westward escape of the crustal material accompanied with the continental collision between India and Eurasia Plate.

  6. Population genetic structure of a sandstone specialist and a generalist heath species at two levels of sandstone patchiness across the Strait of Gibraltar.

    Science.gov (United States)

    Gil-López, Manuel Jesús; Segarra-Moragues, José Gabriel; Ojeda, Fernando

    2014-01-01

    Many habitat specialist species are originally composed of small, discontinuous populations because their habitats are naturally fragmented or patchy. They may have suffered the long-term effects of natural patchiness. Mediterranean heathlands, a representative habitat in the Strait of Gibraltar region, are associated with nutrient-poor, acidic sandstone soils. Sandstone soil patches in the African side of the Strait (Tangier) are, in general, smaller and more scattered than in the European side (Algeciras). In this study, we analyze the effect of this sandstone patchiness on the population genetic diversity and structure of two Erica species from these Mediterranean heathlands that differ in their edaphic specificity, E. australis, sandstone specialist, and E. arborea, generalist. Average levels of within-population genetic diversity and gene flow between populations were significantly lower in Tangier (high sandstone patchiness) than in Algeciras (low patchiness) for the sandstone specialist, whereas no differences between both sides of the Strait were detected in the edaphic generalist. Since most endemic species in Mediterranean heathlands of the Strait of Gibraltar are sandstone specialists, these results highlight an increased vulnerability to loss of genetic diversity and local extinction of the heathland endemic flora in the Tangier side of the Strait of Gibraltar.

  7. Population genetic structure of a sandstone specialist and a generalist heath species at two levels of sandstone patchiness across the Strait of Gibraltar.

    Directory of Open Access Journals (Sweden)

    Manuel Jesús Gil-López

    Full Text Available Many habitat specialist species are originally composed of small, discontinuous populations because their habitats are naturally fragmented or patchy. They may have suffered the long-term effects of natural patchiness. Mediterranean heathlands, a representative habitat in the Strait of Gibraltar region, are associated with nutrient-poor, acidic sandstone soils. Sandstone soil patches in the African side of the Strait (Tangier are, in general, smaller and more scattered than in the European side (Algeciras. In this study, we analyze the effect of this sandstone patchiness on the population genetic diversity and structure of two Erica species from these Mediterranean heathlands that differ in their edaphic specificity, E. australis, sandstone specialist, and E. arborea, generalist. Average levels of within-population genetic diversity and gene flow between populations were significantly lower in Tangier (high sandstone patchiness than in Algeciras (low patchiness for the sandstone specialist, whereas no differences between both sides of the Strait were detected in the edaphic generalist. Since most endemic species in Mediterranean heathlands of the Strait of Gibraltar are sandstone specialists, these results highlight an increased vulnerability to loss of genetic diversity and local extinction of the heathland endemic flora in the Tangier side of the Strait of Gibraltar.

  8. Phytoplankton community and environmental correlates in a coastal upwelling zone along western Taiwan Strait

    Science.gov (United States)

    Wang, Yu; Kang, Jian-hua; Ye, You-yin; Lin, Geng-ming; Yang, Qing-liang; Lin, Mao

    2016-02-01

    Upwelling system in western Taiwan Strait is important for facilitating the fishery production. This study investigated hydro-chemical properties, phytoplankton biomass, phytoplankton species composition, three-dimensional (horizontal, vertical and transect) distribution of phytoplankton abundance, as well as phytoplankton annual variation and the correlation of phytoplankton community with the upwelling of underlying current and nutrients according to samples of Fujian-Guangdong coastal upwelling zone in western Taiwan Strait from August 27 to September 8, 2009. The results manifest that the nutrient-rich cold and high salinity current on the continental shelf of South China Sea upwells to the Fujian-Guangdong coastal waters through Taiwan Bank and the surging strength to surface is weak while strong at 30-m layer. The thermohaline center of coastal upwelling shifts to the east of Dongshan Island and expanded to offshore waters in comparison with previous records. A total of 137 phytoplankton species belonging to 59 genera in 4 phyla are identified excluding the unidentified species. Diatom is the first major group and followed by dinoflagellate. Cyanobacteria mainly composed by three Trichodesmium species account for a certain proportions, while Chrysophyta are only found in offshore waters. The dominant species include Thalassionema nitzschioides, Pseudo-nitzschia pungens, Thalassionema frauenfeldii, Pseudo-nitzschia delicatissima, Rhizosolenia styliformis, Chaetoceros curvisetus, Diplopsalis lenticula and Trichodesmium thiebautii. Phytoplankton community mainly consists of eurythermal and eurytopic species, followed by warm-water species, tropic high-salinity species and oceanic eurythermic species in order. Phytoplankton abundance ranges from 1.00 × 102 ind./L ~ 437.22 × 102 ind./L with an average of 47.36 × 102 ind./L. For vertical distribution, maximum abundance is found at 30 m-depth and the surface comes second. Besides, the abundance below 30 m

  9. Iron isotopes in bottom waters from the Bransfield Strait: Implications for deep water Fe supply

    Science.gov (United States)

    Stichel, Torben; Homoky, William; Connelly, Douglas; Klar, Jessica; Mills, Rachel

    2015-04-01

    Iron (Fe) is an important micro-nutrient in the global ocean. However, its low bioavailability due to poor solubility in oxygenated waters, leads to a strongly limiting character of this trace metal as a nutrient. The major sources of Fe to seawater are largely known (i.e. aeolian dust deposition, riverine and groundwater input, seawater-sediment interaction, and hydrothermal vents) but the relative significance of these sources to the marine Fe supply are not yet well quantified. Areas with low atmospheric inputs, such as the Southern Ocean, are severely Fe limited in surface waters. Here, strong upwelling and a deeply penetrating surface mixed layer fuel one of the largest biogeochemical cycles of trace metals in the global ocean. One significant pathway to bottom waters is the benthic flux of trace metals from hydrothermal systems, where Fe can be stabilised in the water column by different dissolved species. For example, benthic fauna, such as tube-worms, may enhance transportation of dissolved trace metals from pore waters through oxic surface layers of sediments into the deep ocean. Concentrations of total dissolvable Fe (DFe) in these bottom waters have been reported to be significantly higher than surrounding seawater (Aquilina et al., 2014). Here we present DFe isotope composition of bottom water from the Hook Ridge, a shallow (~1100m) sediment covered volcanic feature within a rifted margin. On the basis of Fe isotopes we will determine whether Fe is released by non-reductive dissolution from poorly oxygenated sediments via the presence of tubeworms Sclerolinum spec. This will help to evaluate whether benthic fluxes from hydrothermal fields can be a major source of bioavailable Fe to the deep Southern Ocean. References: Aquilina, A., Homoky, W.B., Hawkes, J. A., Lyons, T.W., Mills, R. a., 2014. Hydrothermal sediments are a source of water column Fe and Mn in the Bransfield Strait, Antarctica. Geochim. Cosmochim. Acta 137, 64-80. doi:10.1016/j.gca.2014.04.003

  10. Larval assemblages of large and medium-sized pelagic species in the Straits of Florida

    Science.gov (United States)

    Richardson, David E.; Llopiz, Joel K.; Guigand, Cedric M.; Cowen, Robert K.

    2010-07-01

    Critical gaps in our understanding of the distributions, interactions, life histories and preferred habitats of large and medium-size pelagic fishes severely constrain the implementation of ecosystem-based, spatially structured fisheries management approaches. In particular, spawning distributions and the environmental characteristics associated with the early life stages are poorly documented. In this study, we consider the diversity, assemblages, and associated habitat of the larvae of large and medium-sized pelagic species collected during 2 years of monthly surveys across the Straits of Florida. In total, 36 taxa and 14,295 individuals were collected, with the highest diversity occurring during the summer and in the western, frontal region of the Florida Current. Only a few species (e.g. Thunnus obesus, T. alalunga, Tetrapturus pfluegeri) considered for this study were absent. Small scombrids (e.g. T. atlanticus, Katsuwonus pelamis, Auxis spp.) and gempylids dominated the catch and were orders of magnitude more abundant than many of the rare species (e.g. Thunnus thynnus,Kajikia albida). Both constrained (CCA) and unconstrained (NMDS) multivariate analyses revealed a number of species groupings including: (1) a summer Florida edge assemblage (e.g. Auxis spp., Euthynnus alleterattus, Istiophorus platypterus); (2) a summer offshore assemblage (e.g. Makaira nigricans, T. atlanticus, Ruvettus pretiosus, Lampris guttatus); (3) an ubiquitous assemblage (e.g. K. pelamis, Coryphaena hippurus, Xiphias gladius); and (4) a spring/winter assemblage that was widely dispersed in space (e.g. trachipterids). The primary environmental factors associated with these assemblages were sea-surface temperature (highest in summer-early fall), day length (highest in early summer), thermocline depth (shallowest on the Florida side) and fluorescence (highest on the Florida side). Overall, the results of this study provide insights into how a remarkable diversity of pelagic species

  11. Comparative Advantages of Cross-strait Aquatic Products Trade and Zhoushan Countermeasures

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In the initial stage,the status quo of aquatic products industry in Taiwan and Zhoushan is analyzed.The aquatic products industry in Tai-wan is characterized by high input,high output,advanced fishery import and export trade,refined and specialized fishery organizations and thedominant role played by the government.However,in Zhoushan,there are many problems in the development of aquatic products industry,featu-ring weak brand consciousness,inadequate famous brand and pillar industries,frequently restricted by green trade barrier and disordered competi-tion of aquatic products market.The comparative advantages of aquatic products at both sides of Taiwan Strait are measured by using revealedcomparative advantage index(RCA) and trade specialized index(TSC),the results show that the aquatic products in both the mainland and Tai-wan have certain market share and competitiveness.The revealed comparative advantage index(RCA) of Taiwan’ aquatic products is higher thatthat in the mainland,while the RCA indices in the mainland and Taiwan all show descending trend;the trade specialized index(TSC) cross straitsis positive,which indicates specialized export,but this specialization also shows descending trend.Taiwan has advanced aquaculture technologyand the mainland owns cheap labor cost and low price,but due to the limited resources in the Taiwan Island and the backward processing technolo-gy of aquatic products in the mainland,the comparativeness of aquatic products in the mainland and Taiwan has slid slightly.Therefore,I probe intothe cooperation modality between Zhoushan and Taiwan in terms of mutual investment in aquatic industry,exchange and training for personnel crossstraits and establishing experimental point of aquatic industry of the Zhoushan Island and Taiwan Island.Besides,countermeasures for enhancingthe international comparativeness of aquatic industry in Zhoushan Island are put forward.

  12. Biogeography of Deep-sea benthic bacteria at regional scale (LTER HAUSGARTEN, Fram Strait, Arctic.

    Directory of Open Access Journals (Sweden)

    Marianne Jacob

    Full Text Available Knowledge on spatial scales of the distribution of deep-sea life is still sparse, but highly relevant to the understanding of dispersal, habitat ranges and ecological processes. We examined regional spatial distribution patterns of the benthic bacterial community and covarying environmental parameters such as water depth, biomass and energy availability at the Arctic Long-Term Ecological Research (LTER site HAUSGARTEN (Eastern Fram Strait. Samples from 13 stations were retrieved from a bathymetric (1,284-3,535 m water depth, 54 km in length and a latitudinal transect (∼ 2,500 m water depth; 123 km in length. 454 massively parallel tag sequencing (MPTS and automated ribosomal intergenic spacer analysis (ARISA were combined to describe both abundant and rare types shaping the bacterial community. This spatial sampling scheme allowed detection of up to 99% of the estimated richness on phylum and class levels. At the resolution of operational taxonomic units (97% sequence identity; OTU3% only 36% of the Chao1 estimated richness was recovered, indicating a high diversity, mostly due to rare types (62% of all OTU3%. Accordingly, a high turnover of the bacterial community was also observed between any two sampling stations (average replacement of 79% of OTU3%, yet no direct correlation with spatial distance was observed within the region. Bacterial community composition and structure differed significantly with increasing water depth along the bathymetric transect. The relative sequence abundance of Verrucomicrobia and Planctomycetes decreased significantly with water depth, and that of Deferribacteres increased. Energy availability, estimated from phytodetrital pigment concentrations in the sediments, partly explained the variation in community structure. Overall, this study indicates a high proportion of unique bacterial types on relatively small spatial scales (tens of kilometers, and supports the sampling design of the LTER site HAUSGARTEN to

  13. Climate effects on historic bluefin tuna captures in the Gibraltar Strait and Western Mediterranean

    Science.gov (United States)

    Ganzedo, Unai; Polanco-Martínez, Josué M.; Caballero-Alfonso, Ángela M.; Faria, Sérgio H.; Li, Jianke; Castro-Hernández, José J.

    2016-06-01

    Historical capture records of bluefin tuna (Thunnus thynnus; BFT hereafter) from the Gibraltar Strait and Western Mediterranean show pronounced short- and long-term fluctuations. Some of these fluctuations are believed to be associated with biological and ecological process, as well as distinct climate factors. For the period of study (1700-1936) of this work, we found a long-term increasing trend in the BFT captures and in the climate variables. After applying a statistical time series analysis of relevant climate variables and long-term tuna capture records, it is highlighted the role played by sea-surface temperature (SST) on bluefin population variations. The most relevant result of this study is the strong correlation found between the total solar irradiance (TSI) - an external component of the climate system - and bluefin captures. The solar irradiance could have affected storminess during the period under study, mainly during the time interval 1700-1810. We suggest physico-biological mechanisms that explain the BFT catch fluctuations in two consecutive time intervals. In the first period, from 1700 to 1810, this mechanism could be high storm and wind activity, which would have made the BFT fisheries activities more difficult by reducing their efficacy. In contrast, during the interval from 1810 to 1907, the effects of wind and storms could be on spawning behaviour and larval ecology, and hence on year class strength, rather than on fish or fisherman's behaviour. These findings open up a range of new lines of enquiry that are relevant for both, fisheries and climate change research.

  14. A Review of Programs That Targeted Environmental Determinants of Aboriginal and Torres Strait Islander Health

    Directory of Open Access Journals (Sweden)

    Kevin Rowley

    2013-08-01

    Full Text Available Objective: Effective interventions to improve population and individual health require environmental change as well as strategies that target individual behaviours and clinical factors. This is the basis of implementing an ecological approach to health programs and health promotion. For Aboriginal People and Torres Strait Islanders, colonisation has made the physical and social environment particularly detrimental for health. Methods and Results: We conducted a literature review to identify Aboriginal health interventions that targeted environmental determinants of health, identifying 21 different health programs. Program activities that targeted environmental determinants of health included: Caring for Country; changes to food supply and/or policy; infrastructure for physical activity; housing construction and maintenance; anti-smoking policies; increased workforce capacity; continuous quality improvement of clinical systems; petrol substitution; and income management. Targets were categorised according to Miller’s Living Systems Theory. Researchers using an Indigenous community based perspective more often identified interpersonal and community-level targets than were identified using a Western academic perspective. Conclusions: Although there are relatively few papers describing interventions that target environmental determinants of health, many of these addressed such determinants at multiple levels, consistent to some degree with an ecological approach. Interpretation of program targets sometimes differed between academic and community-based perspectives, and was limited by the type of data reported in the journal articles, highlighting the need for local Indigenous knowledge for accurate program evaluation. Implications: While an ecological approach to Indigenous health is increasingly evident in the health research literature, the design and evaluation of such programs requires a wide breadth of expertise, including local Indigenous

  15. A Review of Programs That Targeted Environmental Determinants of Aboriginal and Torres Strait Islander Health

    Science.gov (United States)

    Johnston, Leah; Doyle, Joyce; Morgan, Bec; Atkinson-Briggs, Sharon; Firebrace, Bradley; Marika, Mayatili; Reilly, Rachel; Cargo, Margaret; Riley, Therese; Rowley, Kevin

    2013-01-01

    Objective: Effective interventions to improve population and individual health require environmental change as well as strategies that target individual behaviours and clinical factors. This is the basis of implementing an ecological approach to health programs and health promotion. For Aboriginal People and Torres Strait Islanders, colonisation has made the physical and social environment particularly detrimental for health. Methods and Results: We conducted a literature review to identify Aboriginal health interventions that targeted environmental determinants of health, identifying 21 different health programs. Program activities that targeted environmental determinants of health included: Caring for Country; changes to food supply and/or policy; infrastructure for physical activity; housing construction and maintenance; anti-smoking policies; increased workforce capacity; continuous quality improvement of clinical systems; petrol substitution; and income management. Targets were categorised according to Miller’s Living Systems Theory. Researchers using an Indigenous community based perspective more often identified interpersonal and community-level targets than were identified using a Western academic perspective. Conclusions: Although there are relatively few papers describing interventions that target environmental determinants of health, many of these addressed such determinants at multiple levels, consistent to some degree with an ecological approach. Interpretation of program targets sometimes differed between academic and community-based perspectives, and was limited by the type of data reported in the journal articles, highlighting the need for local Indigenous knowledge for accurate program evaluation. Implications: While an ecological approach to Indigenous health is increasingly evident in the health research literature, the design and evaluation of such programs requires a wide breadth of expertise, including local Indigenous knowledge. PMID

  16. Seagrass-Watch: Engaging Torres Strait Islanders in marine habitat monitoring

    Science.gov (United States)

    Mellors, Jane E.; McKenzie, Len J.; Coles, Robert G.

    2008-09-01

    Involvement in scientifically structured habitat monitoring is a relatively new concept to the peoples of Torres Strait. The approach we used was to focus on awareness, and to build the capacity of groups to participate using Seagrass-Watch as the vehicle to provide education and training in monitoring marine ecosystems. The project successfully delivered quality scientifically rigorous baseline information on the seasonality of seagrasses in the Torres Strait—a first for this region. Eight seagrass species were identified across the monitoring sites. Seagrass cover varied within and between years. Preliminary evidence indicated that drivers for seagrass variability were climate related. Generally, seagrass abundance increased during the north-west monsoon ( Kuki), possibly a consequence of elevated nutrients, lower tidal exposure times, less wind, and higher air temperatures. Low seagrass abundance coincided with the presence of greater winds and longer periods of exposure at low tides during the south-east trade wind season ( Sager). No seasonal patterns were apparent when frequency of disturbance from high sedimentation and human impacts was high. Seagrass-Watch has been incorporated in to the Thursday Island High School's Marine Studies Unit ensuring continuity of monitoring. The students, teachers, and other interested individuals involved in Seagrass-Watch have mastered the necessary scientific procedures to monitor seagrass meadows, and developed skills in coordinating a monitoring program and skills in mentoring younger students. This has increased the participants' self-esteem and confidence, and given them an insight into how they may participate in the future management of their sea country.

  17. Polychlorinated biphenyl and heavy metal exposures among fishermen in the Straits of Malacca: neurobehavioural performance.

    Science.gov (United States)

    Mohamad, Alina; Azlan, Azrina; Adon, Mohd Yusoff; Khoo, Hock Eng; Razman, Muhammad Rizal

    2015-01-01

    The aim of this study was to determine the level of exposure to polychlorinated biphenyls (PCBs) and selected heavy metals among fishermen via dietary intake of fish and other seafood from the eastern coast along the Straits of Malacca. This study determined the neurobehavioural performances (based on neurobehavioural core test battery scores) of the fishermen and evaluated the correlations between scores of neurobehavioural core test battery and exposure factors. Ninety fishermen participated in the study. The total fish intakes of the fishermen were measured using a set of food frequency questionnaires. The PCBs contents in the seafood samples ranged between 0.2 and 0.6 pg/g fresh sample. The concentrations of mercury (Hg), arsenic (As), cadmium (Cd), and lead (Pb) in the seafood samples were 1.1-5.4, 0.3-4.4, 0.6-36.1, and 0.02-0.3 μg/g fresh sample, respectively. The PCBs, Hg, As, Cd, and Pb exposures of the fishermen was estimated to be 2.8, 0.02, 4.5, 0.09, and 0.5 pg/kg body weight/day, respectively. PCB and heavy metal exposures through dietary intake of fish and seafood were within the tolerable daily limits. The results of neurobehavioural core test battery revealed that the neurobehavioural performances of the fishermen were not affected due to PCB and heavy metal intoxication. No correlations were found between the exposure and neurobehavioural performance among the fishermen. These data are useful for policy makers to assure the safety and quality of seafood in relation to sea pollution. Although the levels of exposure were low, periodic assessment of the quality of fish and fish products is required due to the polluted seawater.

  18. Nutritional analysis of freshwater and marine amphipods from the Strait of Gibraltar and potential aquaculture applications

    Science.gov (United States)

    Baeza-Rojano, Elena; Hachero-Cruzado, Ismael; Guerra-García, José M.

    2014-01-01

    Four gammarid and four caprellid amphipod species from the Strait of Gibraltar were analyzed to study their nutritional contents: Caprella dilatata, Caprella equilibra, Caprella grandimana, Caprella penantis, Elasmopus rapax, Hyale perieri and Jassa sp. from marine water habitats and Echinogammarus sp. from freshwater habitats. Lipids, proteins, carbohydrates, ash and water contents were measured. Proteins and ash were the most abundant components in all the species, ranging between 37.9 and 44.6% and 29.3 and 39.7% dry weight, respectively. The lipid and carbohydrate contents showed lower levels (5.1-9.6% and 3.1-9.1% dry weight, respectively). No significant differences in general biochemical composition were found between gammarid and caprellid species. The most abundant fatty acids were the polyunsaturated ones (38.3%) with high levels of EPA (20:5(n-3)) with 8.5 to 17.7%, DHA (22:6(n-3)) with 0.9 to 13.6% and ARA (20:4(n-6)) with 1.7 to 5.8%. Caprellid species were characterized by a higher percentage of polyunsaturated fatty acids, while the freshwater gammarid species showed the lowest levels. According to lipid classes, caprellids had higher phospholipids levels and lower triacylglycerol levels, as well as a higher content of polar lipids than the gammarids, being more suitable for their use in aquaculture. Differences in the general biochemical composition between species can be related to habitat characteristics, diets and environmental conditions. Advantages and disadvantages of the use of these organisms in aquaculture are discussed.

  19. The role of the exchanges through the Strait of Gibraltar on the budget of elements in the Western Mediterranean Sea: consequences of human-induced modifications.

    Science.gov (United States)

    Gómez, Fernando

    2003-06-01

    The role of the Strait of Gibraltar on the exchanges of substances between Mediterranean Sea and the Atlantic Ocean is reviewed. The previous estimations have been recalculated by using a similar water flux and compared with the river and atmospheric inputs to the Western Mediterranean Sea. The man-induced changes in the dimensions of the Strait of Gibraltar increasing (planning the sill) or reducing of the cross-section by a total or partial dam are discussed. A total dam will control the sea-level rise in the Mediterranean Sea, but an annual increase of major nutrient concentrations of 1-2% could be expected, lower than the rate of increase of the river and atmospheric inputs in the Western Mediterranean Sea. The increase of the cross-section of the Strait by increasing the depth (planning) at the sill could compensate the increase of the external nutrient inputs.

  20. Characteristics of colored dissolved organic matter (CDOM) in the Arctic outflow in Fram Strait: assessing the changes and fate of terrigenous CDOM in the Arctic Ocean

    DEFF Research Database (Denmark)

    Granskog, M.A.; Stedmon, Colin; Dodd, P.A.

    2012-01-01

    of the Arctic mixed layer and upper halocline waters in the East Greenland Current (EGC). The lowest CDOM concentrations were found in the Atlantic inflow. We show that the salinity-CDOM relationship is not suitable for evaluating conservative mixing of CDOM. The strong correlation between meteoric water...... of absorption at longer wavelengths reflects the loss of high molecular weight material. In contrast, CDOM fluxes through the Fram Strait using September velocity fields from a high-resolution ocean–sea ice model indicate that the net southward transport of terrigenous CDOM through the Fram Strait equals up...... to 50% of the total riverine CDOM input; this suggests that the Fram Strait export is a major sink of CDOM. These contrasting results indicate that we have to constrain the (C)DOM budgets for the Arctic Ocean much better and examine uncertainties related to using tracers to assess conservative mixing...

  1. Fram Strait sea ice export variability and September Arctic sea ice extent over the last 80 years

    Science.gov (United States)

    Smedsrud, Lars H.; Halvorsen, Mari H.; Stroeve, Julienne C.; Zhang, Rong; Kloster, Kjell

    2017-01-01

    A new long-term data record of Fram Strait sea ice area export from 1935 to 2014 is developed using a combination of satellite radar images and station observations of surface pressure across Fram Strait. This data record shows that the long-term annual mean export is about 880 000 km2, representing 10 % of the sea-ice-covered area inside the basin. The time series has large interannual and multi-decadal variability but no long-term trend. However, during the last decades, the amount of ice exported has increased, with several years having annual ice exports that exceeded 1 million km2. This increase is a result of faster southward ice drift speeds due to stronger southward geostrophic winds, largely explained by increasing surface pressure over Greenland. Evaluating the trend onwards from 1979 reveals an increase in annual ice export of about +6 % per decade, with spring and summer showing larger changes in ice export (+11 % per decade) compared to autumn and winter (+2.6 % per decade). Increased ice export during winter will generally result in new ice growth and contributes to thinning inside the Arctic Basin. Increased ice export during summer or spring will, in contrast, contribute directly to open water further north and a reduced summer sea ice extent through the ice-albedo feedback. Relatively low spring and summer export from 1950 to 1970 is thus consistent with a higher mid-September sea ice extent for these years. Our results are not sensitive to long-term change in Fram Strait sea ice concentration. We find a general moderate influence between export anomalies and the following September sea ice extent, explaining 18 % of the variance between 1935 and 2014, but with higher values since 2004.

  2. Freshwater components and transports in the Fram Strait – recent observations and changes since the late 1990s

    Directory of Open Access Journals (Sweden)

    B. Rabe

    2009-03-01

    Full Text Available We present the late summer distribution and transports of freshwater components in the upper western part of the Fram Strait during 1998, 2004 and 2005. Hydrographic data and and water δ18O values are analyzed to distinguish Atlantic Water, ice-melt (IMW and freshwater removal from ice formation (IFW, and Meteoric Water (precipitation and riverine sources; MW. Concentrations of these water masses are combined with volume transport estimates from an inverse model. The average liquid freshwater transport relative to a reference salinity of 34.92, was 2500 km3/yr or 80 mSv southward, which is at the upper end of values reported in the literature. Our results indicate that not only the region of the continental slope but also parts of the East Greenland Shelf are important for freshwater transports.

    The average transports of MW and IFW were 160 mSv (5000 km3/yr and 90 mSv (2800 km3/yr southward, respectively. The southward transport of MW was higher in 2005 than in 1998, but was compensated by a higher IFW transport. These differences in transports were associated with stronger southward velocities and the absence of northward velocities over the continental slope and the eastern East Greenland Shelf in 2005. A simulation using the North Atlantic-Arctic Ocean Sea Ice Model (NAOSIM shows that the high transport of MW in the Fram Strait in 2005 is in agreement with the temporary storage of river water on the Siberian shelf in the mid-1990s, which reached the north of Greenland in 2003. Our results indicate that IFW follows the same pathways as MW before reaching the Fram Strait.

  3. Partitioning and bioaccumulation of PCBs and PBDEs in marine plankton from the Strait of Georgia, British Columbia, Canada

    Science.gov (United States)

    Frouin, Heloise; Dangerfield, Neil; Macdonald, Robie W.; Galbraith, M.; Crewe, Norman; Shaw, Patrick; Mackas, David; Ross, Peter S.

    2013-08-01

    The Strait of Georgia is a large, deep, fjord-like estuary on the southern coast of British Columbia which is subject to local and atmospheric inputs of persistent environmental contaminants. We measured 204 polychlorinated biphenyls (PCBs) and 61 polybrominated diphenyl ethers (PBDEs) seasonally in water (two depths; dissolved and particle-bound) and plankton (vertical tow) samples collected at two stations. Principal components analysis clearly distinguished the dissolved and particulate water fractions and plankton samples, with the latter two compartments associated more with heavier congeners. Bioaccumulation factors (log BAFs) for PCBs and PBDEs in plankton were best described by parabolic relationships against octanol-water partitioning coefficients (log Kow), peaking at a log Kow of 5-7, underscoring the important role of physico-chemical properties in driving the uptake of these persistent contaminants by plankton from water. The estimated total quantity of PCBs (annual average of 0.61 ± SEM 0.12 kg) and PBDEs (annual average of 0.64 ± 0.19 kg) in Strait of Georgia plankton biomass were remarkably similar, highlighting the emergence of currently-used PBDEs as a priority concern. The estimated total of 52.1 ± 8.41 kg of PCBs in water (dissolved + particle-bound) was higher than the estimated 26.8 ± 5.20 kg of PBDEs (dissolved + particle-bound), reflecting the dichotomous use histories for these two contaminant classes. Results provide insight into the biological availability of PCBs and PBDEs to the Strait of Georgia food web, and describe an important initial partitioning process by which the region's endangered killer whales have become highly contaminated.

  4. Locally driven interannual variability of near-surface pH and ΩA in the Strait of Georgia

    Science.gov (United States)

    Moore-Maley, Ben L.; Allen, Susan E.; Ianson, Debby

    2016-03-01

    Declines in mean ocean pH and aragonite saturation state (ΩA) driven by anthropogenic CO2 emissions have raised concerns regarding the trends of pH and ΩA in estuaries. Low pH and ΩA can be harmful to a variety of marine organisms, especially those with calcium carbonate shells, and so may threaten the productive ecosystems and commercial fisheries found in many estuarine environments. The Strait of Georgia is a large, temperate, productive estuarine system with numerous wild and aquaculture shellfish and finfish populations. We determine the seasonality and variability of near-surface pH and ΩA in the Strait using a one-dimensional, biophysical, mixing layer model. We further evaluate the sensitivity of these quantities to local wind, freshwater, and cloud forcing by running the model over a wide range of scenarios using 12 years of observations. Near-surface pH and ΩA demonstrate strong seasonal cycles characterized by low pH, aragonite-undersaturated waters in winter and high pH, aragonite-supersaturated waters in summer. The aragonite saturation horizon generally lies at ˜20 m depth except in winter and during strong Fraser River freshets when it shoals to the surface. Periods of strong interannual variability in pH and aragonite saturation horizon depth arise in spring and summer. We determine that at different times of year, each of wind speed, freshwater flux, and cloud fraction are the dominant drivers of this variability. These results establish the mechanisms behind the emerging observations of highly variable near-surface carbonate chemistry in the Strait.

  5. Different population structure in genus Luciobarbus Heckel, 1843 (Actinopterygii, Cyprinidae on both sides of the Strait of Gibraltar

    Directory of Open Access Journals (Sweden)

    Miriam Casal-Lopez

    2015-12-01

    Here, through a phylogeographic study based on mitochondrial molecular markers, we found different structures on both sides of the Strait of Gibraltar, as well as faunistic connections probably established on both sides during Miocene. Our results show that populations may have followed different and complex histories and species have suffered diverse events of vicariance and dispersion. While north Moroccan population show a well-defined structure, showing not only unique haplotypes, but different species, the case of the southern populations of the Iberian endemism, Luciobarbus sclateri Günther, 1868, differs substantially.

  6. Genetic structure and population differentiation of the Mediterranean pioneer spiny broom Calicotome villosa across the Strait of Gibraltar

    DEFF Research Database (Denmark)

    Arroyo, Juan; Aparicio, Abelardo; Albadalejo, Rafael G.;

    2008-01-01

    of species during the Pleistocene, as a consequence of the lowering of sea level and climate changes associated with the Ice Ages. In the present study, we report a multilevel hierarchical investigation of the genetic diversity of Calicotome villosa, a common pioneer legume shrub, at the regional scale......The region around the Strait of Gibraltar is considered to be one of the most relevant ‘hot spots’ of biodiversity in the Mediterranean Basin due to its historical, biogeographical, and ecological features. Prominent among these is its role as a land bridge for the migration and differentiation...

  7. Epidemiology, etiology, and motivation of alcohol misuse among Australian Aboriginal and Torres Strait Islanders of the Northern Territory: a descriptive review.

    Science.gov (United States)

    Ramamoorthi, Ramya; Jayaraj, Rama; Notaras, Leonard; Thomas, Mahiban

    2015-01-01

    The per capita alcohol consumption of the Northern Territory, Australia, is second highest in the world, estimated 15.1 liters of pure alcohol per year. Alcohol abuse is a major public health concern among Aboriginal and Torres Strait Islander people in Australia. The Aboriginal and Torres Strait Islanders in the Northern Territory consume approximately 16.9 liters of pure alcohol per year. This descriptive review is based on current published and grey literature in the context of high risk alcohol use, with a special focus on the epidemiological, etiological, and social factors, to predict alcohol misuse among the Australian Aboriginal and Torres Strait Islanders in Northern Territory. The methodology involved a descriptive search on PubMed, Northern Territory government reports, health databases, and Web sites with an emphasis on the etiology and epidemiology of high-risk alcohol consumption among the Australian Aboriginal and Torres Strait Islanders of the Northern Territory. This review has its own limitations because it does not rely on systematic review methodologies. However, it presents real data on the motives for binge drinking and alcohol-related violent assaults of this vulnerable population. Alcohol abuse and alcohol-related harms are considerably high among the rural and remote communities where additional research is needed. High-risk alcohol misuse within Australian Aboriginal and Torres Strait Islanders communities often leads to a series of physical and social consequences. This review highlights the need for culturally appropriate intervention approaches focusing on alcohol misuse among the Aboriginal and Torres Strait Islanders population of the Northern Territory.

  8. 中国、美国与1958年台湾海峡危机%China, America and Taiwan Straits Crisis in 1958

    Institute of Scientific and Technical Information of China (English)

    赵学功

    2004-01-01

    @@ Three so-called crises occurred during the 1950s and the 1960s between China and America, which brought the two countries to the brink of war. There are considerable amount of valuable writings about the first Taiwan Straits crisis but relatively few about the second Taiwan Strait crisis. This paper tries to illustrate the decision-making processes of both sides and the impact of this event on Sino-US relations in the wake of the declassification of US diplomatic documents and emergence of relevant Chinese document in recent years.

  9. On the seasonal cycles and variability of Florida Straits, Ekman and Sverdrup transports at 26° N in the Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    C. P. Atkinson

    2010-10-01

    Full Text Available Since April 2004 the RAPID array has made continuous measurements of the Atlantic Meridional Overturning Circulation (AMOC at 26° N. Two key components of this system are Ekman transport zonally integrated across 26° N and western boundary current transport in the Florida Straits. Whilst measurements of the AMOC as a whole are somewhat in their infancy, this study investigates what useful information can be extracted on the variability of the Ekman and Florida Straits transports using the decadal timeseries already available. Analysis is also presented for Sverdrup transports zonally integrated across 26° N.

    The seasonal cycles of Florida Straits, Ekman and Sverdrup transports are quantified at 26° N using harmonic analysis of annual and semi-annual constituents. Whilst Sverdrup transport shows clear semi-annual periodicity, calculations of seasonal Florida Straits and Ekman transports show substantial interannual variability due to contamination by variability at non-seasonal frequencies; the mean seasonal cycle for these transports only emerges from decadal length observations. The Florida Straits and Ekman mean seasonal cycles project on the AMOC with a combined peak-to-peak seasonal range of 3.5 Sv. The combined seasonal range for heat transport is 0.40 PW.

    The Florida Straits seasonal cycle possesses a smooth annual periodicity in contrast with previous studies suggesting a more asymmetric structure. No clear evidence is found to support significant changes in the Florida Straits seasonal cycle at sub-decadal periods. Whilst evidence of wind driven Florida Straits transport variability is seen at sub-seasonal and annual periods, a model run from the 1/4° eddy-permitting ocean model NEMO is used to identify an important contribution from internal oceanic variability at sub-annual and interannual periods. The Ekman transport seasonal cycle possesses less symmetric structure, due in part to different seasonal transport

  10. TAIWAN, The Treasure of China

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ The island of Taiwan lies some 120 kilometers off the southeastern coast of mainland China, across the Taiwan Strait, and has an area of 35,801 km2(13,822.8 sq mi). The East China Sea lies to the north, the Philippine Sea to the east, the Luzon Strait directly to the south and the South China Sea to the southwest.

  11. The impact of Kuroshio water on the source water of the southeastern Taiwan Strait:numerical results

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wenzhou; ZHUANG Xuefen; CHEN Chentung Arthur; HUANG Tinghsuan

    2015-01-01

    Model output from a Pacific basin-wide three-dimensional physical-biogeochemical model during the period of 1991 to 2008 was used to investigate the impact of Kuroshio water on the source water of the southeastern Taiwan Strait. Based on the characteristic salinities of both Kuroshio water and the South China Sea water, a Kuroshio impact index (KII) was designed to measure the degree of impact. The KII correlates significantly with the northeast-southwest component of wind stress, but the former lags the latter by approximately two months. The correlation coefficient between them increases from 0.267 4 to 0.852 9, with a lag time increasing from 0 to 63 days. The impact of Kuroshio Water is greater in winter and spring than in summer and autumn. At the interannual time scale, El Niño and La Niña events play an important role in impacting the KII. During El Niño events, more Kuroshio water contributes to the source water of the southeastern Taiwan Strait. Conversely, during La Niña events, less Kuroshio water contributes to the source water.

  12. Recent wind driven high sea ice export in the Fram Strait contributes to Arctic sea ice decline

    Directory of Open Access Journals (Sweden)

    L. H. Smedsrud

    2011-05-01

    Full Text Available Arctic sea ice area decrease has been visible for two decades, and continues at a steady rate. Apart from melting, the southward drift through Fram Strait is the main loss. We present high resolution sea ice drift across 79° N from 2004 to 2010. The ice drift is based on radar satellite data and correspond well with variability in local geostrophic wind. The underlying current contributes with a constant southward speed close to 5 cm s−1, and drives about 33 % of the ice export. We use geostrophic winds derived from reanalysis data to calculate the Fram Strait ice area export back to 1957, finding that the sea ice area export recently is about 25 % larger than during the 1960's. The increase in ice export occurred mostly during winter and is directly connected to higher southward ice drift velocities, due to stronger geostrophic winds. The increase in ice drift is large enough to counteract a decrease in ice concentration of the exported sea ice. Using storm tracking we link changes in geostrophic winds to more intense Nordic Sea low pressure systems. Annual sea ice export likely has a significant influence on the summer sea ice variability and we find low values in the 60's, the late 80's and 90's, and particularly high values during 2005–2008. The study highlight the possible role of variability in ice export as an explanatory factor for understanding the dramatic loss of Arctic sea ice the last decades.

  13. Evidence of MIS 5 sea-level highstands in Gebel Mousa coast (Strait of Gibraltar, North of Africa)

    Science.gov (United States)

    Abad, M.; Rodríguez-Vidal, J.; Aboumaria, K.; Zaghloul, M. N.; Cáceres, L. M.; Ruiz, F.; Martínez-Aguirre, A.; Izquierdo, T.; Chamorro, S.

    2013-01-01

    The Last Interglacial is considered the most suitable episode from which to infer patterns of rapid sea-level change since its climatic conditions were similar to those of the present interglacial. However, specifying the true position of its sea level with high accuracy is very troublesome in the absence of sedimentological, erosional or even palaeontological markers. This study investigates the morphosedimentary evidence (beach deposits, cliff, notch and shore platform) of two highstands registered and dated during MIS 5 stage by U-series dating in the North of Morocco (Strait of Gibraltar). Bioerosive notches and mixed siliciclastic and carbonate deposits, high energy beaches with algal bioherms, were formed in coastal environments during MIS 5a. A sea-level height of + 10 m asl can be inferred for this substage. The record of MIS 5e substage is less defined in the geomorphological record, consisting of backshore/foreshore deposits located at + 13 to + 15 m asl. A tectonic uplift rate of ~ 0.1 mm/yr has been estimated for the last 130 kyr. These data are consistent with models of coastal uplifting calculated for the Strait of Gibraltar.

  14. Interannual variability of remotely sensed chlorophyll a during an autumn monsoon transitional period in the Taiwan Strait

    Institute of Scientific and Technical Information of China (English)

    ZHANG Caiyun; HONG Huasheng

    2014-01-01

    The time series of multiple sources of satellite data are used to examine the interannual variability of chlo-rophyll a concentration (Chl a) and its relation to the physical environment during the autumn monsoon transitional period in the Taiwan Strait (TWS). The satellite data included the Chl a concentration and sea surface temperature (SST) derived from the Moderate Resolution Imaging Spectroradiometer (MODIS)/Aqua as well as the multi-sensors merged wind products from 2002 to 2012. The results show that the aver-age Chl a concentration of the whole TWS is mainly contributed by the northern TWS. The average Chl a in the northern TWS is 3.6 times that in the southern TWS. The maximum variability of Chl a is located in the frontal regions between the cold Zhe-Min Coastal Water and the strait warm water. The temporal change of Chl a concentration is different in the northern and southern TWS. The changes in the relative strength of the cold and warm water masses is suggested to be the dominant processes in controlling the phytoplankton growth in the northern TWS, while there is wind-induced mixing in the southern TWS. Additionally, La Niña events exhibited complex effects on the interannual variability of Chl a concentration in autumn. The long-term time series of physical and biological observations are especially needed to better understand how the TWS complex ecosystem responds to climate variations.

  15. Inferring sources of polycyclic aromatic hydrocarbons (PAHs) in sediments from the western Taiwan Strait through end-member mixing analysis.

    Science.gov (United States)

    Li, Tao; Sun, Guihua; Ma, Shengzhong; Liang, Kai; Yang, Chupeng; Li, Bo; Luo, Weidong

    2016-11-15

    Concentration, spatial distribution, composition and sources of polycyclic aromatic hydrocarbons (PAHs) were investigated based on measurements of 16 PAH compounds in surface sediments of the western Taiwan Strait. Total PAH concentrations ranged from 2.41 to 218.54ngg(-1). Cluster analysis identified three site clusters representing the northern, central and southern regions. Sedimentary PAHs mainly originated from a mixture of pyrolytic and petrogenic in the north, from pyrolytic in the central, and from petrogenic in the south. An end-member mixing model was performed using PAH compound data to estimate mixing proportions for unknown end-members (i.e., extreme-value sample points) proposed by principal component analysis (PCA). The results showed that the analyzed samples can be expressed as mixtures of three end-members, and the mixing of different end-members was strongly related to the transport pathway controlled by two currents, which alternately prevail in the Taiwan Strait during different seasons. Copyright © 2016. Published by Elsevier Ltd.

  16. A Multi-Criterion Analysis of Cross-Strait Co-Opetitive Strategy in the Crystalline Silicon Solar Cell Industry

    Directory of Open Access Journals (Sweden)

    Hsiao-Chi Chen

    2014-01-01

    Full Text Available The research adopts multi-criterion analysis to face cross-strait cooperative and competitive (co-opetitive strategies problem in the crystalline silicon solar cell industry between Taiwan and China. The analysis framework is based on the national competitiveness. The Analytical Hierarchy Process (AHP approach and TOPSIS analysis are applied to analyze firm-level data, gathered from the solar cell companies across the Taiwan Strait. For the Taiwanese firms, their relative national competitiveness lies in technology development, domestic market, international competition in related industries, and subsidy policy. For the Chinese firms, domestic market, procurement conditions, customization, intellectual resources, risk capital, and human quality are found to be their competitive advantages. Both China and Taiwan have entered into the emerging solar cell industry, with an aim to climb beyond the ladder of catch up. The results have shown that Taiwan and China can explore the possibility of forging strategic alliances by exploiting national competitiveness on the demand side. Above all, the paper has managed to spotlight demand conditions as the crucial factors for China and Taiwan to enhance their international competitiveness in the emerging solar cell industry.

  17. Environmental and health benefits from designating the Marmara Sea and the Turkish Straits as an emission control area (ECA).

    Science.gov (United States)

    Viana, M; Fann, N; Tobías, A; Querol, X; Rojas-Rueda, D; Plaza, A; Aynos, G; Conde, J A; Fernández, L; Fernández, C

    2015-03-17

    Ship emissions degrade air quality and affect human health, and are increasingly becoming a matter of concern. Sulfur emission control areas (ECA), specific coastal regions where only low-sulfur fuels may be consumed by ocean-going ships, have proven to be useful tools to reduce ship-sourced air pollution along the North American, Canadian, and European North and Baltic Sea coastlines. The present work assesses the environmental and health benefits which would derive from designating an ECA in the Marmara Sea and the Turkish Straits (50 000 ships/year; 23 million inhabitants). Results show evidence that implementing an ECA would be technically viable and that it would reduce ship-sourced PM10 and PM2.5 ambient concentrations in Istanbul by 67%, and SO2 by 90%. The reduction of the air pollution burden on health was quantified as 210 hospital admissions from exposure to PM10, 290 hospital admissions from exposure to SO2, and up to 30 premature deaths annually due to ECA emission controls. Consequently, the designation of an ECA in the Marmara Sea and the Turkish Straits is evaluated as a positive, technically viable and real-world measure to reduce air pollution from ships in Turkey.

  18. The "other" side of labor reform: accounts of incarceration and resistance in the Straits Settlements penal system, 1825-1873.

    Science.gov (United States)

    Pieris, Anoma

    2011-01-01

    The rhetoric surrounding the transportation of prisoners to the Straits Settlements and the reformative capacity of the penal labor regime assumed a uniform subject, an impoverished criminal, who could be disciplined and accordingly civilized through labor. Stamford Raffles, as lieutenant governor of Benkulen, believed that upon realizing the advantages of the new colony, criminals would willingly become settlers. These two colonial prerogatives of labor and population categorized transportees into laboring classes where their exploitation supposedly brought mutual benefit. The colonized was collectively homogenized as a class of laborers and evidence to the contrary, of politically challenging and resistant individuals was suppressed. This paper focuses on two prisoners who were incriminated during the anti-colonial rebellions of the mid-nineteenth century and were transported to the Straits Settlements. Nihal Singh, a political prisoner from Lahore, was incarcerated in isolation to prevent his martyrdom and denied the supposed benefits of labor reform. Conversely, Tikiri Banda Dunuwille, a lawyer from Ceylon was sent to labor in Melaka as a form of humiliation. Tikiri’s many schemes to evade labor damned him in the eyes of the authorities. The personal histories of these two individuals expose how colonial penal policy recognized and manipulated individual differences during a time of rising anti-colonial sentiment. The experiences of these prisoners, the response of their communities and the voices of their descendents offer us a very different entry point into colonial penal history.

  19. SPATIAL VARIATION OF Zn GEOCHEMICAL FRACTIONS IN THE SURFACE SEDIMENTS OF THE STRAITS OF MALACCA: NATURAL OR ANTHROPOGENIC?

    Institute of Scientific and Technical Information of China (English)

    Chee Kong Yap; Ahmad Ismail; Soon Guan Tan

    2005-01-01

    Total concentrations of Zn in the sediments of the offshore and intertidal areas of the west coast of Peninsular Malaysia were recently reported in the literaturs. However, total concentrations of metals in the sediment samples do not reflect the portion or carrier phase which is attributable to anthropogenic activities and those of natural origins.In this work, geochemical fraction of Zn in the sediments of the same areas was studied and the potential use of CV as an indicator of Zn pollution was determined. The geochemical study by using sequential extraction technique revealed tions, respectively, in the sediments while most of the total zinc concentrations (offshore: 70%; intertidal: 52%)found in the sediments could be mostly due to natural origins (nonresistant fraction). Thus, the Zn levels in the Straits of Malacca should not pose a risk to the liying organisms. Based on Spearman's correlation coefficients, the source of Zn contamination in the Straits of Malacca was mainly contributed by the intertidal coastal area rather than offshore area. The present study also indicated the coefficient of variation can be used as a potential indicator of total summation of geochemical Zn concentrations in the coastal sediment but of different geochemical of Zn needs further validation.

  20. Characterization of Fram Strait Sea Ice Conditions Using the NASA SIERRA Unmanned Aircraft System

    Science.gov (United States)

    Maslanik, J. A.; Crocker, R. I.; Wegrzyn, K.; Fowler, C.; Herzfeld, U. C.; Long, D.; Kwok, R.; Fladeland, M. M.; Bui, P.

    2009-12-01

    In addition to record decreases in summer ice extent, the Arctic Ocean has also experienced extensive loss of the oldest, thickest sea ice types. The significance of this loss on overall sea ice mass and on the stability of the ice cover depends on how the thickness and physical properties of these older ice types vary with age, and on the degree to which a transition to generally thinner first-year ice might be in part compensated for by ice accumulating through increased ridging and rafting. Due to the difficulty of accessing and surveying a wide range ice types in the field, detailed, spatially extensive information regarding how factors such as thickness, ridging, and melt ponding differ with ice type are relatively rare. To address this, an experiment was carried out to map surface conditions at high spatial resolution using a low- and relatively slow-flying unmanned aircraft system (UAS) operated over the various ice types that are transported through the Fram Strait region, where ice with different ages and life cycle histories leaves the Arctic Basin. This effort - the “Characterization of Arctic Sea Ice Experiment” (CASIE) - measured ice surface roughness, thickness, ice ridging, floe morphology and melt pond characteristics to quantify differences among ice types and to assist in validating retrievals from satellite sensors. The nature of the flights - relatively hazardous low-altitude, long-range flying under Arctic summer conditions over ocean - made the experiment particularly well suited for UAS. The aircraft selected for the project was the National Aeronautics and Space Administration’s SIERRA, which provided 10 hour/1000 km flight range with a payload capacity of 25 kg; sufficient to meet the experiment’s remote sensing goals of acquiring coincident, multisensor data over large areas. Flights were carried out from the Ny-Alesund research base in Svalbard during July 10th. through July 29th., 2009, yielding 2500 km of coverage over sea ice

  1. Photosynthetic use of inorganic carbon in deep-water kelps from the Strait of Gibraltar.

    Science.gov (United States)

    García-Sánchez, María Jesús; Delgado-Huertas, Antonio; Fernández, José Antonio; Flores-Moya, Antonio

    2016-03-01

    Mechanisms of inorganic carbon assimilation were investigated in the four deep-water kelps inhabiting sea bottoms at the Strait of Gibraltar; these species are distributed at different depths (Saccorhiza polysiches at shallower waters, followed by Laminaria ochroleuca, then Phyllariopsis brevipes and, at the deepest bottoms, Phyllariopsis purpurascens). To elucidate the capacity to use HCO3(-) as a source of inorganic carbon for photosynthesis in the kelps, different experimental approaches were used. Specifically, we measured the irradiance-saturated gross photosynthetic rate versus pH at a constant dissolved inorganic carbon (DIC) concentration of 2 mM, the irradiance-saturated apparent photosynthesis (APS) rate versus DIC, the total and the extracellular carbonic anhydrase (CAext), the observed and the theoretical photosynthetic rates supported by the spontaneous dehydration of HCO3(-) to CO2, and the δ(13)C signature in tissues of the algae. While S. polyschides and L. ochroleuca showed photosynthetic activity at pH 9.5 (around 1.0 µmol O2 m(-2) s(-1)), the activity was close to zero in both species of Phyllariopsis. The APS versus DIC was almost saturated for the DIC values of natural seawater (2 mM) in S. polyschides and L. ochroleuca, but the relationship was linear in P. brevipes and P. purpurascens. The four species showed total and CAext activities but the inhibition of the CAext originated the observed photosynthetic rates at pH 8.0 to be similar to the theoretical rates that could be supported by the spontaneous dehydration of HCO3(-). The isotopic (13)C signatures ranged from -17.40 ± 1.81 to -21.11 ± 1.73 ‰ in the four species. Additionally, the δ(13)C signature was also measured in the deep-water Laminaria rodriguezii growing at 60-80 m, showing even a more negative value of -26.49 ± 1.25 ‰. All these results suggest that the four kelps can use HCO3(-) as external carbon source for photosynthesis mainly by the action of external CAext, but

  2. The Strait of Gibraltar as a melting pot for plant biodiversity

    Science.gov (United States)

    Rodríguez-Sánchez, Francisco; Pérez-Barrales, Rocío; Ojeda, Fernando; Vargas, Pablo; Arroyo, Juan

    2008-11-01

    The S Iberian Peninsula and NW Africa constitute one of the main hotspots for plant biodiversity within the Mediterranean Basin. At the core of this hotspot, across the Strait of Gibraltar, lies a smaller region whose singular Cenozoic history and ecological features have created a distinct, nested sub-hotspot. In particular, an important relict flora, a high endemism, and the dominance of vegetation types other than the paradigmatic Mediterranean-type sclerophyllous forests and shrublands, are biogeographical features of paramount relevance. These singular environments may have provided suitable mesic habitats for stable human populations in this region throughout the Quaternary. Here we explore the possible causes of the unique biodiversity of this region. First, we show that endemism is associated with poor soils and mild Mediterranean climate, whereas relictness is primarily associated with riparian and humid habitats which might have remained relatively stable since the Late Tertiary. We then review and provide new results on lineage and molecular diversity of some taxa based on their evolutionary relationships inferred from phylogenetic and phylogeographical analyses. These indicate that long-lived plants, such as trees, tend to show some discontinuity in effective gene flow, in comparison with short-lived and pioneer plants. Colonization abilities rather than dispersal vectors appear to be a crucial factor. We also analyze the role of microevolutionary processes that generate plant biodiversity in terms of reproductive features involved in lineage formation, such as breeding system, pollination biology and postdispersal regeneration. The few available studies show that this region is prone to changes in reproductive systems, associated with both abiotic and biotic conditions in the new habitats that plants face during colonization. Dispersal and regeneration ecology is especially important for relict species, as most of these species face some biotic (e

  3. Stirring by deep cyclones and the evolution of Denmark strait overflow water observed at line W

    Science.gov (United States)

    Andres, M.; Toole, J. M.; Torres, D. J.; Smethie, W. M.; Joyce, T. M.; Curry, R. G.

    2016-03-01

    Shipboard velocity and water property data from 18 transects across the North Atlantic Deep Western Boundary Current (DWBC) near 40 °N are examined to study the evolution of the Denmark Strait Overflow Water (DSOW) component of the DWBC and mixing between DSOW and the interior. The examined transects along Line W - which stretches from the continental shelf south of New England to Bermuda - were made between 1994 and 2014. The shipboard data comprise measurements at regular stations of velocity from lowered acoustic Doppler current profilers, CTD profiles and trace gas chlorofluorocarbon (CFC) concentrations from bottle samples at discrete depths. Comparison of the Line W velocity sections with concurrent sea surface height maps from satellite altimetry indicates that large cyclones in the deep ocean accompany intermittent quasi-stationary meander troughs in the Gulf Stream path at Line W. A composite of 5 velocity sections along Line W suggests that a typical cyclone reaches swirl speeds of greater than 30 cm s-1 at 3400-m depth and has a radius (distance between the center and the maximum velocity) of 75 km. Tracer data suggest that these cyclones affect not only the deep velocity structure along Line W, but also provide a mechanism for water exchange between the DWBC's DSOW and the interior. Vigorous exchange is corroborated by a mismatch in the CFC-11:CFC-12 and CFC-113:CFC-12 ratio ages calculated for DSOW at Line W. During the most recent 5-year period (2010-2014), a decrease in DSOW density has been driven by warming (increasing by almost 0.1 °C) as salinity has increased only slightly (by 0.003, which is close to the 0.002 uncertainty of the measurements). The abyssal ocean offshore of the DWBC and Gulf Stream and deeper than 3000-m depth has freshened at a rate of 6×10-4 yr-1 since at least 2003. Density here remains nearly unchanged over this period, due to temperature compensation, though a linear cooling trend in the abyssal ocean (to compensate the

  4. Analysis on the Evolution of Regional Economic Disparity in the West Coast of the Strait

    Institute of Scientific and Technical Information of China (English)

    Geng Jianzhong; Wu Dianting; Zhao Xiaofang; Lu Qi

    2008-01-01

    With the implementation of reform and opening-up,the overall economy of China has made brilliant achievements;meanwhile,however,the economic disparity has been enlarging among some regions,and between the city and the countryside.The existence and evolution of this kind of economic disparity is concerned with social stability,sustainable development and the construction of harmonious society,which has gradually become the hotspot in social economic development.The West Coast of the Strait (WCS) located in southeast littoral areas is adjacent to the Pearl and Yangtze River Delta in the south and north and faces Taiwan Province in the east.The stability and development of this region has vital political and economic meaning in the social economic development of our country.It has important theoretical meaning and practical value to research the form,characteristics and evolution of regional economic disparity in the WCS.Based on insightful analysis on existing study results on the WCS,the paper defines the connotation and extension.By a series of absolute and comparative relative evaluation indexes and taking the WCS since 1992 as the study object,the paper makes analysis on different scales including three regions,four regions,20 cities and 152 counties,quantitatively evaluates the level,characteristics and evolution of the regional economic disparity and compares the regional economic disparity on different scales.The main conclusions are as follows:the variation trend of the absolute disparity of the whole region is obvious and stable,which has presented an inflating trend; the comparative variation trend on a large scale has waved,The comparative disparity of the three regions increased annually from 1992 to around 2000,which had a decreasing trend from around 2000 to 2005; the comparative variation trend on a small scale was not stable,which showed an annual increase of four regions,20 cities and 152 counties from 1992 to around 2003 and a decrease from around

  5. Technical Note: Mean sea level variation in the Singapore Strait from long-term tide data

    Directory of Open Access Journals (Sweden)

    P. Tkalich

    2012-06-01

    Full Text Available Winds over the South China Sea (SCS are primarily responsible for the observed variability in sea level anomalies (SLAs in the Singapore Strait (SS. The present study focuses on remote forcing contributing to local mean sea level changes in the SS in seasonal and inter-annual scales, and relating the long term mean sea level variation to El Niño/ENSO. As Tanjong Pagar (TP tide station in the SS has nearly 23.5 yr (1984–2007 of time series data with less data gaps, this data was subject to harmonic and sea level analyses. The mean sea level changes suggest that the fluctuations are quasi-periodic. Rising and falling of sea level is noticed atleast 7 times in a period of 15 yr, with 3 distinct sharp falls (1984–1987, 1989–1992 and 1995–1996 and 4 sharp rises (1987–1988, 1992–1993, 1994–1995 and 1997–1999. These sea level falls are related to El Niño events. When we segregated the results into 2 time spans, we find that from 1984 to 1999 the sea level was on the rising trend in spite of sharp falls, and from 1999 to 2007 on gradual falling trend. More or less similar trend was observed by other researchers for the SCS with altimetry data. During the El Niño periods of 1987 and 1992, the inter-annual MSL variability is the highest, of the order of 7 cm. In one of the events, sea level recovered from a fall of 60 mm (in 1987 to a rise of 40 mm (in 1988. During 1992 to 1999, sea level was continuously on rising trend (from −50 mm to +60 mm, except in one year (1995–1996. The analysis shows a MSL rise rate of 15.7 mm yr−1, which is very closer to MSL in the SCS. The average rate of sea level rise around Singapore as shown by the Tanjong Pagar tidal station is 1.6 mm yr−1, and this matches with the global sea level rise.

  6. Observation and modelling of turbulent mixing in the Kuril and Aleutian Straits and impact of its 18.6-year period tidal cycle on ocean and climate

    Science.gov (United States)

    Yasuda, I.; Tanaka, Y.; Itoh, S.; Hasumi, H.; Komatsu, K.; Osafune, S.; Yagi, M.; Tanaka, T.; Kaneko, H.; Ikeya, T.; Konda, S.; Nishioka, J.; Nakatsuka, T.; Katsumata, K.; Tatebe, H.; Watanabe, Y.; Hiroe, Y.; Nakamura, T.

    2012-12-01

    Direct turbulent observations in the Kuril Straits and Aleutian Straits reveal that tide-induced strong vertical mixing corresponds to strong shear of combined diurnal tidal and/or mean currents and significantly modifies the water-mass and potential vorticity distribution. Bi-decadal variability synchronized with 18.6-year period moon-tidal cycle were found in various parts of the ocean and climate indices: water-mass variability in the subarctic North Pacific, especially near the strong diurnal tide regions as Kuril Straits and Aleutian Islands, and in long-term climate indices as Pacific Decadal Oscillation (PDO) and El-Nino and Southern Oscillation (ENSO) in proxy-reconstructed records. In low-frequency part of the PDO and SOI records, negative (positive)-PDO and positive (negative)-SOI tend to occur in the 4-6-th (10-12-th) year after the maximum diurnal tide, which is consistent with the climate model experiments with locally enhanced vertical mixing around Kuril Straits showing that tidal mixing and its variability could generate bi-decadal variability in ocean and climate. Ocean and climate model experiments with parameterized tidal mixing explain some of the water-mass modifications and bi-decadal variability of water-masses and climate.

  7. The arctic species Heterostigma separ Ärnbäck-Christie-Linde, 1924 (Ascidiacea: Pyuridae) in the strait og Gibraltar (southern Spain)

    NARCIS (Netherlands)

    Naranjo, S.A.; Garcia-Gomez, J.C.

    1993-01-01

    The arctic species Heterostigma separ Arnbäck-Christie-Linde, 1924, a component of the interstitial fauna in coastal soft bottoms from Nova Zembla, was found in gravels of Algeciras Bay (Gibraltar Strait, Southern Spain). This new record constitutes the southernmost limit of the geographical range o

  8. The arctic species Heterostigma separ Ärnbäck-Christie-Linde, 1924 (Ascidiacea: Pyuridae) in the strait og Gibraltar (southern Spain)

    NARCIS (Netherlands)

    Naranjo, S.A.; Garcia-Gomez, J.C.

    1993-01-01

    The arctic species Heterostigma separ Arnbäck-Christie-Linde, 1924, a component of the interstitial fauna in coastal soft bottoms from Nova Zembla, was found in gravels of Algeciras Bay (Gibraltar Strait, Southern Spain). This new record constitutes the southernmost limit of the geographical range o

  9. Physical, biological and optical oceanographic data collected from moorings deployed in the Bering Strait from 08/27/2007 to 09/02/2009 (NODC Accession 0062860)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — From 2007 to 2009, a total of eight moorings were deployed, including A1W, A1, and A1E in the Russian channel of the Strait, A2W, A2, A4W (A4W for 2007 to 2008 and...

  10. Crustal and upper mantle S-wave velocity structures across the Taiwan Strait from ambient seismic noise and teleseismic Rayleigh wave analyses

    Science.gov (United States)

    Huang, Y.; Yao, H.; Wu, F. T.; Liang, W.; Huang, B.; Lin, C.; Wen, K.

    2013-12-01

    Although orogeny seems to have stopped in western Taiwan large and small earthquakes do occur in the Taiwan Strait. Limited studies have focused on this region before and were barely within reach for comprehensive projects like TAICRUST and TAIGER for logistical reasons; thus, the overall crustal structures of the Taiwan Strait remain unknown. Time domain empirical Green's function (TDEGF) from ambient seismic noise to determine crustal velocity structure allows us to study an area using station pairs on its periphery. This research aims to resolve 1-D average crustal and upper mantle S-wave velocity (Vs) structures alone paths of several broadband station-pairs across the Taiwan Strait; 5-120 s Rayleigh wave phase velocity dispersion data derived by combining TDEGF and traditional surface wave two-station method (TS). The average Vs structures show significant differences in the upper 15 km as expected. In general, the highest Vs are observed in the coastal area of Mainland China and the lowest Vs appear along the southwest offshore of the Taiwan Island; they differ by about 0.6-1.1 km/s. For different parts of the Strait, the Vs are lower in the middle by about 0.1-0.2 km/s relative to those in the northern and southern parts. The overall crustal thickness is approximately 30 km, much thinner and less variable than under the Taiwan Island.

  11. The spectral optical properties and relative radiant heating contribution of dissolved and particulate matter in the surface waters across the Fram Strait

    DEFF Research Database (Denmark)

    Pavlov, A.K.; Granskog, M.A.; Stedmon, Colin

    The Fram Strait is the key region for exchange processes between Arctic Ocean and North Atlantic. With two major near-surface currents, the warm and salty West Spitsbergen Current and cold low-salinity East Greenland Current, its waters encompass two distinct oceanographic environments. During...

  12. Characteristics of colored dissolved organic matter (CDOM) in the Arctic outflow in the Fram Strait: Assessing the changes and fate of terrigenous CDOM in the Arctic Ocean

    NARCIS (Netherlands)

    Granskog, M.A.; Stedmon, C.A.; Dodd, P.A.; Amon, R.M.W.; Pavlov, A.K.; de Steur, L.; Hansen, E.

    2012-01-01

    Absorption coefficients of colored dissolved organic matter (CDOM) were measured together with salinity, delta O-18, and inorganic nutrients across the Fram Strait. A pronounced CDOM absorption maximum between 30 and 120 m depth was associated with river and sea ice brine enriched water, characteris

  13. Impacts of a buoyant strait outflow on the plankton production characteristics of an adjacent semi-enclosed basin: A case study of the Marmara Sea

    Science.gov (United States)

    Oguz, Temel

    2017-09-01

    As documented by observational studies, the buoyant outflows emanating from straits and rivers with large amounts of nutrients and biogenic materials cause marked changes in the biochemical characteristics of the adjacent receiving water bodies. Here, using a three-dimensional biophysical model of the Marmara Sea-Bosphorus Strait two-layer exchange flow system and configuring it for the winter phytoplankton blooming period with limited top-down control, we show that complex buoyancy-induced basin-scale circulation is driven by the buoyant jet emanating from a strait, which sustains enhanced production even in the absence of any nutrient flux from its upstream source region and lateral point sources around the sea. In the supercritical flow regime downstream of the strait exit, strong upward motion introduced by the hydraulically controlled outflow dynamics injects subsurface nutrients into the upper layer. Those accumulated within the adjacent anticyclonic bulge to the right of the outflow plume then support relatively high phytoplankton production, whereas strong currents limit phytoplankton production along the main jet axis. Furthermore, topographically controlled anticyclonic circulation within the lower layer around the deep northern basin induces upwelling due to the divergence of cross-isobath, uphill flow and causes the nutrient enrichment of the upper layer. This cumulative response, together with the additional contribution of nutrient recycling and the horizontal distribution of nutrients and biota by the mesoscale-dominated circulation system, maintain a highly productive system within the sea, which is consistent with previous observations.

  14. On a small collection of Valvifera (Crustacea Isopoda) from the Magellan Strait, with description of Platidotea magellanica n.gen. n.sp

    NARCIS (Netherlands)

    Park, Ja-Yang; Wägele, J. Wolfgang

    1995-01-01

    Redescriptions of 5 arcturid species from the Strait of Magellan are presented, the validity of the genus Rectarcturus is discussed. Platidotea magellanica n.gen. n.sp. is described. It is a new type of idoteid isopod, with flattened body and antennae, probably adaptated to life in sandy bottoms.

  15. CEPA对海峡两岸经贸关系的影响%The Effects of CEPA on the Relations Across the Taiwan Straits

    Institute of Scientific and Technical Information of China (English)

    赖文凤; 陈乔之

    2004-01-01

    The signing of CEPA aggravates the competitive pressure on Taiwanese businessmen who live and do business in the Mainland. So there is an urgent need for them to push ahead the realization of the normalization and institutionalization of trade and economic ties across the straits.

  16. The spectral optical properties and relative radiant heating contribution of dissolved and particulate matter in the surface waters across the Fram Strait

    DEFF Research Database (Denmark)

    Pavlov, A.K.; Granskog, M.A.; Stedmon, Colin

    The Fram Strait is the key region for exchange processes between Arctic Ocean and North Atlantic. With two major near-surface currents, the warm and salty West Spitsbergen Current and cold low-salinity East Greenland Current, its waters encompass two distinct oceanographic environments. During...

  17. A subglacial landform assemblage on the outer-shelf of M'Clure Strait, Canadian Arctic, ploughed by deglacial iceberg keels

    Science.gov (United States)

    Batchelor, Christine; Dowdeswell, Julian; Dowdeswell, Evelyn; Todd, Brian

    2015-04-01

    M'Clure Strait in the Canadian Beaufort Sea is one of the largest cross-shelf troughs in the High Arctic, with a length of over 1000 km and a maximum cross-trough width of around 250 km. M'Clure Strait has been suggested to be the former location of a fast-flowing ice stream which drained the northwestern margin of the Laurentide Ice Sheet during the Late Wisconsinan glaciation, and probably also during a number of earlier Quaternary full-glacial periods. The Late Wisconsinan ice stream in M'Clure Strait is interpreted to have extended to the shelf break between 21 and 16 ka ago, before undergoing rapid retreat. The ice stream has been suggested to have undergone vigorous episodes of activity during the last deglaciation; ice export events from the M'Clure Strait ice stream may have been responsible for the formation of distinctive layers of ice-rafted debris in the Arctic Ocean during regional deglaciation. Here, we present multibeam bathymetric data of the seafloor of outermost M'Clure Strait. Low rates of post-glacial sedimentation have led to the preservation of an unusual assemblage of cross-cutting subglacial, glacifluvial and glacimarine landforms on the M'Clure Strait seafloor. The assemblage of glacigenic landforms records the advance and retreat of a fast-flowing ice stream. Highly-elongate mega-scale glacial lineations (MSGLs) provide evidence for the advance of the last, Late Wisconsinan ice stream through M'Clure Strait to within at least 8 km of the shelf break. The preservation of the MSGLs and the lack of ice-flow transverse landforms indicate rapid ice retreat from this region of the outer-shelf. Trough-parallel sinuous esker-like ridges of sediment are also identified. These were probably formed by the sedimentary infilling of ice-walled subglacial meltwater conduits during deglaciation. This interpretation requires considerable volumes of meltwater and sediment to have been transported within subglacial channels beneath the M'Clure Strait ice

  18. Climate change and sea ice: Shipping accessibility on the marine transportation corridor through Hudson Bay and Hudson Strait (1980–2014

    Directory of Open Access Journals (Sweden)

    Jonathan Andrews

    2017-03-01

    Full Text Available Shipping traffic has been increasing in Hudson Strait and Hudson Bay and the shipping route through these waters to the Port of Churchill may soon become a federally-designated transportation corridor. A dataset on passive microwave-based sea ice concentration was used to characterize the timing of the ice on the shipping corridor to the Port between 1980 and 2014. Efforts were made to produce results in a readily accessible format for stakeholders of the shipping industry; for example, open water was defined using a sea ice concentration threshold of ≤ 15% and results are presented in terms of real dates instead of anomalies. Between 1980 and 2014, the average breakup date on the corridor was July 4, the average freeze-up date was November 25, and the average length of the open water season was 145 days. However, each of these three variables exhibited significant long-term trends and spatial variability over the 34-year time period. Regression analysis revealed significant linear trends towards earlier breakup (–0.66 days year–1, later freeze-up (+0.52 days year–1, and a longer open water season (+1.14 days year–1 along the shipping corridor between 1980 and 2014. Moreover, the section of the corridor passing through Hudson Strait displayed significantly stronger trends than the two sections in Hudson Bay (i.e., “Hudson Islands” and “Hudson Bay”. As a result, sea ice timing in the Hudson Strait section of the corridor has diverged from the timing in the Hudson Bay sections. For example, the 2010–2014 median length of the open water season was 177 days in Hudson Strait and 153 days in the Hudson Bay sections. Finally, significant linear relationships were observed amongst breakup, freeze-up, and the length of the open water season for all sections of the corridor; correlation analysis suggests that these relationships have greatest impact in Hudson Strait.

  19. Recall of anti-tobacco advertising and information, warning labels and news stories in a national sample of Aboriginal and Torres Strait Islander smokers.

    Science.gov (United States)

    Nicholson, Anna K; Borland, Ron; Sarin, Jasmine; Wallace, Sharon; van der Sterren, Anke E; Stevens, Matthew; Thomas, David P

    2015-06-01

    To describe recall of anti-tobacco advertising (mainstream and targeted), pack warning labels, and news stories among a national sample of Aboriginal and Torres Strait Islander smokers, and to assess the association of these messages with attitudes that support quitting, including wanting to quit. A quota sampling design was used to recruit participants from communities served by 34 Aboriginal community-controlled health services and one community in the Torres Strait. We surveyed 1643 Aboriginal and Torres Strait Islander smokers from April 2012 to October 2013. Frequency of recall of advertising and information, warning labels and news stories; recall of targeted and local advertising; attitudes about smoking and wanting to quit. More smokers recalled often noticing warning labels in the past month (65%) than recalled advertising and information (45%) or news stories (24%) in the past 6 months. When prompted, most (82%) recalled seeing a television advertisement. Just under half (48%) recalled advertising that featured an Aboriginal or Torres Strait Islander person or artwork (targeted advertising), and 16% recalled targeted advertising from their community (local advertising). Frequent recall of warning labels, news stories and advertising was associated with worry about health and wanting to quit, but only frequent advertising recall was associated with believing that society disapproves of smoking. The magnitude of association with relevant attitudes and wanting to quit increased for targeted and local advertising. Strategies to tackle Aboriginal and Torres Strait Islander smoking should sustain high levels of exposure to anti-tobacco advertising, news stories and warning labels. More targeted and local information may be particularly effective to influence relevant beliefs and subsequently increase quitting.

  20. PCDD and PCDF exposures among fishing community through intake of fish and shellfish from the Straits of Malacca.

    Science.gov (United States)

    Azlan, Azrina; Nasir, Nurul Nadiah Mohamad; Shamsudin, Norashikin; Rahman, Hejar Abdul; Khoo, Hock Eng; Razman, Muhammad Rizal

    2015-07-21

    Exposure to PCDD/PCDF (dioxin and furan) through consumption of fish and shellfish is closely related to the occurrence of skin diseases, such as chloracne and hyperpigmentation. This study aimed to determine the exposure of PCDD/PCDF and its congeners in fish and shellfish obtained from different regions of the Straits of Malacca among the fishing community. The risk of fish and shellfish consumption and exposure to PCDD/PCDF among fishermen living in coastal areas of the Straits were evaluated based on a cross-sectional study involving face to face interviews, blood pressure and anthropometric measurements, and administration of food frequency questionnaires (FFQ). Skin examination was done by a dermatologist after the interview session. Determination of 17 congeners of PCDD/PCDF in 48 composite samples of fish and shellfish was performed based on HRGC/HRMS analysis. The total PCDD/PCDF in the seafood samples ranged from 0.12 to 1.24 pg WHO-TEQ/g fresh weight (4.6-21.8 pg WHO-TEQ/g fat). No significant difference found for the concentrations of PCDD/PCDF between the same types of seafood samples obtained from the three different regions. The concentrations of the most potent congener, 2,3,7,8-TCDD in the seafood samples ranged from 0.01 to 0.11 pg WHO-TEQ/g FW (1.9 pg WHO-TEQ/g fat). A positive moderate correlation was found between the fat contents and concentrations of PCDD/PCDF determined in the seafood samples. The total PCDD/PCDF in all seafood samples were below the 1 pg WHO-TEQ/g fresh weight, with the exception of grey eel-catfish. The respondents had consumed fish and shellfish with the amounts ranging between 2.02 g and 44.06 g per person per day. The total PCDD/PCDF exposures through consumption of fish and shellfish among the respondents were between 0.01 and 0.16 pg WHO-TEQ/kg BW/day. With regard to the two PCDD/PCDF-related skin diseases, no chloracne case was found among the respondents, but 2.2% of the respondents were diagnosed to have