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Sample records for south pacific subtropical

  1. Plastic pollution in the South Pacific subtropical gyre.

    Science.gov (United States)

    Eriksen, Marcus; Maximenko, Nikolai; Thiel, Martin; Cummins, Anna; Lattin, Gwen; Wilson, Stiv; Hafner, Jan; Zellers, Ann; Rifman, Samuel

    2013-03-15

    Plastic marine pollution in the open ocean of the southern hemisphere is largely undocumented. Here, we report the result of a (4489 km) 2424 nautical mile transect through the South Pacific subtropical gyre, carried out in March-April 2011. Neuston samples were collected at 48 sites, averaging 50 nautical miles apart, using a manta trawl lined with a 333 μm mesh. The transect bisected a predicted accumulation zone associated with the convergence of surface currents, driven by local winds. The results show an increase in surface abundance of plastic pollution as we neared the center and decrease as we moved away, verifying the presence of a garbage patch. The average abundance and mass was 26,898 particles km(-2) and 70.96 g km(-2), respectively. 88.8% of the plastic pollution was found in the middle third of the samples with the highest value of 396,342 particles km(-2) occurring near the center of the predicted accumulation zone. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Relationship Between Intraseasonal Oscillation and Subtropical Wind Maxima Over the South Pacific Ocean

    Science.gov (United States)

    Vincent, Dayton G.; Hurrell, James W.; Speth, P.; Sperling, T.; Funk, A.; Zube, S.

    1991-01-01

    The significance of tropical heat sources on higher latitude jet streams has been examined by numerous investigators. Hurrell and Vincent (1990) provide a summary of many of these investigations in their observational case study of the relationship between tropical heating and subtropical wind maxima in the Southern Hemisphere during SOP-1, FGGE. They showed that the divergent outflow from tropical heating associated with the South Pacific Convergence Zone (SPCZ), acted on by the coriolis force, was an important factor in maintaining the subtropical jet on the poleward side of the SPCZ during the period, 6-20 January 1979. They found a similar, but weaker relationship, over the southern Indian Ocean from 3-17 February 1979, a period when the SPCZ heating was greatly reduced and the jet was essentially non-existent. Since their findings were based on a case study and involved the use of the highly-specialized FGGE data set, the natural questions which arose were: (1) Is this relationship a regular feature of the circulation over the South Pacific? and, (2) If so, can it be detected with a routine data set? Another question posed by Hurrell and Vincent in their papers was:(3) How important was the intraseasonal oscillation in causing the enhanced heating and divergent outflow in the Pacific Ocean in January and southern Indian Ocean in February? The purpose of the present paper is to address the answer to these three questions. To accomplish this, some circulation features for an entire warm season in the Southern Hemisphere were examined. The year selected was 1984-85, and the warm season consisted of the 6-month period, 1 November 1984 - 30 April 1985. This period was chosen because there were numerous cases of the westerly wind maxima over the South Pacific and the intraseasonal oscillation was well documented.

  3. On the decade-long deep-ocean warming in the subtropical South Pacific Ocean

    Science.gov (United States)

    Volkov, Denis; Lee, Sang-Ki; Landerer, Felix; Lumpkin, Rick

    2017-04-01

    The persistent energy imbalance at the top of the atmosphere, inferred from satellite measurements, indicates that the Earth climate system continues to accumulate excess heat. As only sparse and irregular measurements of ocean heat below 2000-m depth exist, one of the most challenging questions in global climate change studies is whether the excess heat has already penetrated into the deep-ocean. The deep-ocean warming can initiate and advance in the regions where the air-sea interactions and ocean internal dynamics favor transfer of heat from the surface to the deeper waters. It is important to identify such regions, preferably using as many independent observing systems as possible, and to understand the associated dynamics. Combination of the present-day satellite and in situ observing systems has a potential to provide a more complete view on the horizontal and vertical distribution of heat in the ocean. While the uncertainties associated with the observing systems are decreasing, the combined use of satellite altimetry, GRACE, and Argo measurements may theoretically become an ideal method to indirectly infer deep-ocean temperature changes below 2000-m depth. The difference between the total sea level (observed by altimetry) and the mass-related sea level (observed by GRACE) gives the steric (due to changes in seawater density) sea level variability, which is mostly a function of the full-depth heat content. The deep-ocean (below 2000-m) contribution can be inferred indirectly, as the difference between the satellite-based (altimetry minus GRACE) and Argo-based steric sea level. Carrying out a comprehensive analysis of satellite and in situ measurements, and atmospheric re-analyses, here we report on deep-ocean warming signatures observed in the subtropical South Pacific during the past decade of 2005-2014. We show that the local accumulation of heat accounted for up to a quarter of the global ocean heat increase, with directly and indirectly inferred deep

  4. Nitrous oxide distribution and its origin in the central and eastern South Pacific Subtropical Gyre

    Directory of Open Access Journals (Sweden)

    J. Charpentier

    2007-09-01

    Full Text Available The mechanisms of microbial nitrous oxide (N2O production in the ocean have been the subject of many discussions in recent years. New isotopomeric tools can further refine our knowledge of N2O sources in natural environments. This study compares hydrographic, N2O concentration, and N2O isotopic and isotopomeric data from three stations along a coast-perpendicular transect in the South Pacific Ocean, extending from the center (Sts. GYR and EGY of the subtropical oligotrophic gyre (~26° S; 114° W to the upwelling zone (St. UPX off the central Chilean coast (~34° S. Although AOU/N2O and NO3 trends support the idea that most of the N2O (mainly from intermediate water (200–600 m comes from nitrification, N2O isotopomeric composition (intramolecular distribution of 15N isotopes expressed as SP (site preference of 15N shows low values (10 to 12permil that could be attributed to the production through of microbial nitrifier denitrification (reduction of nitrite to N2O mediated by ammonium oxidizers. The coincidence of this SP signal with high – stability layer, where sinking organic particles can accumulate, suggests that N2O could be produced by nitrifier denitrification inside particles. It is postulated that deceleration of particles in the pycnocline can modify the advection - diffusion balance inside particles, allowing the accumulation of nitrite and O2 depletion suitable for nitrifier denitrication. As lateral advection seems to be relatively insignificant in the gyre, in situ nitrifier denitrification could account for 40–50% of the N2O produced in this layer. In contrast, coastal upwelling system is characterized by O2 deficient condition and some N deficit in a eutrophic system. Here, N2O accumulates up to 480% saturation, and isotopic and

  5. Spatial variability of phytoplankton pigment distributions in the Subtropical South Pacific Ocean: comparison between in situ and predicted data

    Directory of Open Access Journals (Sweden)

    J. Ras

    2008-03-01

    Full Text Available In the frame of the BIOSOPE cruise in 2004, the spatial distribution and structure of phytoplankton pigments was investigated along a transect crossing the ultra-oligotrophic South Pacific Subtropical Gyre (SPSG between the Marquesas Archipelago (141° W–8° S and the Chilean upwelling (73° W–34° S. A High Performance Liquid Chromatography (HPLC method was improved in order to be able to accurately quantify pigments over such a large range of trophic levels, and especially from strongly oligotrophic conditions. Seven diagnostic pigments were associated to three phytoplankton size classes (pico-, nano and microphytoplankton. The total chlorophyll-α concentrations [TChlα] in surface waters were the lowest measured in the centre of the gyre, reaching 0.017 mg m−3. Pigment concentrations at the Deep Chlorophyll Maximum (DCM were generally 10 fold the surface values. Results were compared to predictions from a global parameterisation based on remotely sensed surface [TChlα]. The agreement between the in situ and predicted data for such contrasting phytoplankton assemblages was generally good: throughout the oligotrophic gyre system, picophytoplankton (prochlorophytes and cyanophytes and nanophytoplankton were the dominant classes. Relative bacteriochlorophyll-α concentrations varied around 2%. The transition zone between the Marquesas and the SPSG was also well predicted by the model. However, some regional characteristics have been observed where measured and modelled data differ. Amongst these features is the extreme depth of the DCM (180 m towards the centre of the gyre, the presence of a deep nanoflagellate population beneath the DCM or the presence of a prochlorophyte-enriched population in the formation area of the high salinity South Pacific Tropical Water. A coastal site sampled in the eutrophic upwelling zone, characterised by recently upwelled water, was significantly and unusually enriched in picoeucaryotes, in

  6. 20-50-day oscillation of summer Yangtze rainfall in response to intraseasonal variations in the subtropical high over the western North Pacific and South China Sea

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Jiangyu; Wu, Guoxiong [Institute of Atmospheric Physics, Chinese Academy of Sciences, State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG), P.O. Box 9804, Beijing (China); Sun, Zhang [Institute of Atmospheric Physics, Chinese Academy of Sciences, State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG), P.O. Box 9804, Beijing (China); Zhejiang Meteorological Observatory, Hangzhou (China)

    2010-04-15

    The spatio-temporal variability in summer rainfall within eastern China is identified based on empirical orthogonal function (EOF) analysis of daily rain-gauge precipitation data for the period 1979-2003. Spatial coherence of rainfall is found in the Yangtze Basin, and a wavelet transform is applied to the corresponding principal component to capture the intraseasonal oscillation (ISO) of Yangtze rainfall. The ensemble mean wavelet spectrum, representing statistically significant intraseasonal variability, shows a predominant oscillation in summer Yangtze rainfall with a period of 20-50 days; a 10-20-day oscillation is pronounced during June and July. This finding suggests that the 20-50-day oscillation is a major agent in regulating summer Yangtze rainfall. Composite analyses reveal that the 20-50-day oscillation of summer Yangtze rainfall arises in response to intraseasonal variations in the western North Pacific subtropical high (WNPSH), which in turn is modulated by a Rossby wave-like coupled circulation-convection system that propagates northward and northwestward from the equatorial western Pacific. When an anomalous cyclone associated with this Rossby wave-like system reaches the South China Sea (SCS) and Philippine Sea, the WNPSH retreats northeastward due to a reduction in local pressure. Under these conditions, strong monsoonal southwesterlies blow mainly toward the SCS-Philippine Sea, while dry conditions form in the Yangtze Basin, with a pronounced divergent flow pattern. In contrast, the movement of an anomalous anticyclone over the SCS-Philippine Sea results in the southwestward extension of the WNPSH; consequently, the tropical monsoonal southwesterlies veer to the northeast over the SCS and then converge toward the Yangtze Basin, producing wet conditions. Therefore, the 20-50-day oscillation of Yangtze rainfall is also manifest as a seesaw pattern in convective anomalies between the Yangtze Basin and the SCS-Philippine Sea. A considerable zonal

  7. The impact of ENSO on the South Atlantic Subtropical Dipole Mode

    Science.gov (United States)

    Rodrigues, Regina; Campos, Edmo; Haarsma, Reindert

    2015-04-01

    The impact of the El Niño - Southern Oscillation (ENSO) on the South Atlantic subtropical dipole mode (SASD) is investigated using both observations and model simulations. The SASD is the dominant mode of coupled ocean-atmosphere variability in the South Atlantic. This study focuses on austral summer, when both ENSO and SASD peak. We show that negative SASD events are associated with central Pacific El Niño events by triggering the Pacific-South America wave train (PSA). The latter resembles the 3rd leading mode of atmospheric variability in the Southern Hemisphere (PSA2) and causes a weakening and meridional shift of the South Atlantic subtropical high, which then generates the negative SASD events. On the other hand, a strengthening of the South Atlantic subtropical high related to central La Niña teleconnections causes positive SASD events. Our results show that the PSA2, triggered by central Pacific ENSO events, connects the tropical Pacific to the Atlantic. This connection is absent from eastern Pacific ENSO events, which appear to initiate the 2nd leading mode of atmospheric variability in the Southern Hemisphere (PSA1). It is for this reason that previous studies have found weak correlations between ENSO and SASD. These findings can improve the climate prediction of southeast South America and southern Africa since these regions are affected by sea surface temperature anomalies of both Pacific and Atlantic oceans.

  8. Fiji in the South Pacific.

    Science.gov (United States)

    Scott, Rosalind; Semaan, Leslie

    This text introduces Fiji and other island nations located in the Pacific, the world's largest ocean. Cut off from the world by vast expanses of water, these people developed a unique culture. Contents include: Teacher Overview, Geography of the South Pacific Islands, History of the South Pacific, Fiji, Traditional Village Life, Yaquna Ceremony,…

  9. Marine debris collects within the North Pacific Subtropical Convergence Zone.

    Science.gov (United States)

    Pichel, William G; Churnside, James H; Veenstra, Timothy S; Foley, David G; Friedman, Karen S; Brainard, Russell E; Nicoll, Jeremy B; Zheng, Quanan; Clemente-Colón, Pablo

    2007-08-01

    Floating marine debris, particularly derelict fishing gear, is a hazard to fish, marine mammals, turtles, sea birds, coral reefs, and even human activities. To ameliorate the economic and environmental impact of marine debris, we need to efficiently locate and retrieve dangerous debris at sea. Guided by satellite-derived information, we made four flights north of Hawaii in March and April 2005. During these aerial surveys, we observed over 1800 individual pieces of debris, including 122 derelict fishing nets. The largest debris concentrations were found just north of the North Pacific Transition Zone Chlorophyll Front (TZCF) within the North Pacific Subtropical Convergence Zone (STCZ). Debris densities were significantly correlated with sea-surface temperature (SST), chlorophyll-a concentration (Chla), and the gradient of Chla. A Debris Estimated Likelihood Index (DELI) was developed to predict where high concentrations of debris would be most likely in the North Pacific during spring and early summer.

  10. Bacterial and eukaryotic intact polar lipids in the eastern subtropical South Pacific: Water-column distribution, planktonic sources, and fatty acid composition

    Science.gov (United States)

    Van Mooy, Benjamin A. S.; Fredricks, Helen F.

    2010-11-01

    Fatty acids are generally the most abundant lipid molecules in plankton, and thus play a central role in the cycling of organic matter in the upper ocean. These fatty acids are primarily derived from intact polar diacylglycerolipids (IP-DAGs), which compose cell membranes in plankton. The molecular diversity of IP-DAGs in the upper ocean remains to be fully characterized, and the advent of high performance liquid chromatography/electrospray ionization-mass spectrometry (HPLC/ESI-MS) approaches have now provided the opportunity to readily analyze IP-DAGs from marine planktonic communities. We used HPLC/ESI-MS to determine the concentrations of three classes of phospholipids (phosphatidlyglycerol (PG), phosphatidylethanolamine (PE), and phosphatidylcholine (PC)), three classes of betaine lipids (diacylglyceryl trimethylhomoserine (DGTS), diacylglyceryl hydroxymethyl-trimethyl-β-alanine (DGTA), and diacylglyceryl carboxyhydroxymethylcholine (DGCC)), and three classes of glycolipids (monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglycerol (DGDG), and sulfoquinovosyldiacylglycerol (SQDG)) in plankton filtered (>0.2 μm) from seawater collected within the euphotic zone of the eastern South Pacific. The distributions of these IP-DAGs along the cruise transect provided important new insights on their tentative planktonic sources. Complementary data from our cruise, a principle components analysis of our IP-DAG concentrations, observed fatty acid compositions of IP-DAG classes and published IP-DAG distributions in pure cultures of plankton suggest that heterotrophic bacteria were the dominant sources of PG and PE, while MGDG and SQDG originated primarily from Prochlorophytes. The origins of the other classes of IP-DAGs were less clear, although it is likely that PC, DGTS, DGTA, and DGCC were derived primarily from eukaryotic phytoplankton. The molecular distributions of fatty acids attached to the different classes of IP-DAGs were generally distinct from one

  11. Interannual variability of the subtropical countercurrent eddies in the North Pacific associated with the Western-Pacific teleconnection pattern

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    Chow, Chun Hoe; Tseng, Yu-heng; Hsu, Huang-Hsiung; Young, Chih-Chieh

    2017-07-01

    The connection and the relevant dynamical processes between oceanic eddies in the North Pacific Subtropical Countercurrent (STCC) region and the atmospheric Western-Pacific (WP) teleconnection is investigated on interannual timescales. North of the STCC region, the local northerly surface wind anomalies cool the ocean surface during negative phases of the WP teleconnection. The local surface cooling modifies the meridional gradient of sea surface temperature (SST), strengthening the SST front at its south. In the STCC region, we show the meridional gradient of surface-heat-flux forcing caused by the local surface cooling is the same order as the Ekman-convergence forcing. The strengthened SST front then leads to the pycnocline shoaling in the STCC region, which can also enhance the growth of baroclinic instability to produce more oceanic eddies, in addition to the enhanced STCC proposed previously. These dynamics are reversed during the positive phases of WP teleconnection.

  12. GEOTRACES Eastern South Pacific: Characterizing Water Mass Properties and Timescales

    Science.gov (United States)

    Martin, M.; Fine, R. A.; Happell, J. D.

    2014-12-01

    In the fall 2013 an eastern South Pacific GEOTRACES transect was occupied along about 12°S from the coast to 150°W. The objective is to characterize the water mass properties as compared with historical data and considering climate modes of variability. Tracer ages (CFCs and SF6) are used to provide constraints on time scales of physical and biogeochemical processes. The GEOTRACES transect contains eutrophic and oligotrophic stations. In between, there is a large oxygen minimum zone (OMZ) created by a shadow zone in the subtropical gyre circulation. The major water masses in the upper 1500 m are the Antarctic Intermediate Water (AAIW) found below the 27 σθ, Subantarctic Mode Water located above the AAIW and below the 26.5 σθ, South Pacific Eastern Subtropical Mode Water found along 25.5 σθ near 100°W, South Pacific Subtropical Under Water follows 25 σθ, and South Pacific Subtropical Water is located at the surface west of 110°W. Water with SF6 ages of less than 30 years are found above 26.5 σθ. The highest apparent oxygen utilization rates (AOUR) found in the coastal region are likely due to the upwelling in this region. The central gyre region shows the lowest AOUR, corresponding with the oligotrophic conditions. In between, the OMZ, ranging from 80⁰W to about 120⁰W, has a median AOUR. An analysis of our data compared to WOCE data at 4 co-locations shows changes in the water properties and biogeochemical processes over a 20 year time period. This analysis suggests an expansion and a strengthening of the OMZ in the past 20 years. While there is a decrease in oxygen content within the OMZ, there is a slight increase in AOU in the western part of the OMZ.

  13. Wind-induced subduction at the South Atlantic subtropical front

    Science.gov (United States)

    Calil, Paulo H. R.

    2017-10-01

    The South Atlantic Subtropical Front, associated with the eastward-flowing South Atlantic Current, separates the colder, nutrient-rich waters of the subpolar gyre from the warmer, nutrient-poor waters of the subtropical gyre. Perturbations to the quasi-geostrophic, eastward flow generate meanders and filaments which induce cross-frontal exchange of water properties. Down-front winds transport denser waters from the South over warm waters from the North, inducing convective instability and subduction. Such processes occur over spatial scales of the order of 1 km and thus require high horizontal spatial resolution. In this modeling study, a high-resolution (4 km) regional grid is embedded in a basin-wide configuration (12 km) of the South Atlantic Ocean in order to test the importance of submesoscale processes in water mass subduction along the subtropical front. Stronger and more numerous eddies obtained in the high-resolution run yield more intense zonal jets along the frontal zone. Such stronger jets are more susceptible to instabilities, frontogenesis, and the generation of submesoscale meanders and filaments with O(1) Rossby number. As a consequence, vertical velocities larger than 100 md 1 are obtained in the high-resolution run, one order of magnitude larger than in the low-resolution run. Wind-driven subduction occurs along the frontal region, associated with negative Ertel potential vorticity in the surface layer. Such processes are not observed in the low-resolution run. A passive tracer experiment shows that waters with density characteristics similar to subtropical mode waters are preferentially subducted along the frontal region. The wind-driven buoyancy flux is shown to be much larger than thermal or haline fluxes during the wintertime, which highlights the importance of the frictional component in extracting PV from the surface ocean and inducing subduction, a process that has been overlooked in subtropical mode water formation in the region.

  14. SPICE: South PacIfic Circulation and Climate Experiment

    Science.gov (United States)

    Ganachaud, A.; Kessler, W.; Brassington, G.; Wijffels, S.; Ridgway, K.; Cai, W.; Holbrook, N.; Bowen, M.; Sutton, P.; Qiu, B.; Timmermann, A.; Roemmich, D.; Sprintall, J.; Cravatte, S.; Gourdeau, L.; Aung, T.

    2007-12-01

    South Pacific thermocline waters are transported from the subtropical gyre center in the westward flowing South Equatorial Current, towards the southwestern Pacific Ocean-a major circulation pathway that redistributes water from the subtropics to the equator and southern ocean. The transit in the Coral Sea is potentially of great importance to tropical climate prediction because changes in either the temperature or the amount of water arriving at the equator have the capability to modulate the ENSO cycle and thereby produce basin-scale climate feedbacks. The Southwest Pacific is a region of complex ocean circulation. The South Equatorial Current is split in strong zonal jets upon encountering the island archipelago. Those jets partition on the Australian eastern boundary to feed the East Australian Current for the southern branch and the North Queensland Current and eventually the Equatorial Undercurrent for the northern branch. This climatological view of the current system is subject to substantial seasonal and inter-annual modulation. This circulation, and its influence on remote and regional climate, is poorly understood due to the lack of appropriate measurements. Ocean and atmosphere scientists from Australia, France, New Zealand and the United States initiated an international research project under the auspices of CLIVAR to comprehend the Southwest Pacific ocean circulation and its direct and indirect influence on the climate and environment. The outline of a feasible, regionally-coordinated experiment to measure, study and monitor the ocean circulation, to validate and improve numerical models, and to integrate with assimilating systems is presented. This project, named SPICE, reflects a strong sense that substantial progress can be made through collaboration among South Pacific national research groups, with full coordination with broader South Pacific projects.

  15. Tropical Pacific sea-surface temperatures and preceding sea level pressure anomalies in the subtropical North Pacific

    Science.gov (United States)

    Anderson, Bruce T.

    2003-12-01

    The correspondence of sea-surface temperature (SST) anomalies to changes in antecedent large-scale sea level pressure anomalies is investigated using reanalysis data. By statistically examining linearly coupled precursor sea level pressure fields and subsequent SST fields for different lag periods, it is possible to isolate a precursor mode of sea level pressure (SLP) variability in the central subtropical North Pacific that precedes variations in the January-March El Niño/Southern Oscillation (ENSO) by approximately 12-15 months. A sea level pressure index, which captures the important characteristics of this precursor mode of variability, is developed and evaluated. It is shown that both analyzed and observed versions of the index are significantly correlated with the January-March ENSO one year later. The SLP index is then used to examine the evolution of the surface circulation and temperature structures leading up to mature ENSO events. Initially, the January-March subtropical North Pacific SLP anomalies are associated with changes in the intensity of the subtropical trade wind regime over the North Pacific, as well as with SST anomalies over the eastern equatorial Pacific and subtropical central Pacific. In agreement with the correlation statistics associated with the SLP and lagged NINO3.4 indices, both the sea level pressure field and the SST field subsequently develop ENSO-like structures over the course of the following year. Significant discussion of these results and pertinent areas of future research are provided within the broader context of the ENSO system.

  16. Microbiome of Trichodesmium Colonies from the North Pacific Subtropical Gyre

    OpenAIRE

    Mary R. Gradoville; Byron C Crump; Letelier, Ricardo M.; Church, Matthew J; White, Angelicque E.

    2017-01-01

    Filamentous diazotrophic Cyanobacteria of the genus Trichodesmium, often found in colonial form, provide an important source of new nitrogen to tropical and subtropical marine ecosystems. Colonies are composed of several clades of Trichodesmium in association with a diverse community of bacterial and eukaryotic epibionts. We used high-throughput 16S rRNA and nifH gene sequencing, carbon (C) and dinitrogen (N2) fixation assays, and metagenomics to describe the diversity and functional potentia...

  17. Enhanced warming of the subtropical mode water in the North Pacific and North Atlantic

    Science.gov (United States)

    Sugimoto, Shusaku; Hanawa, Kimio; Watanabe, Tomowo; Suga, Toshio; Xie, Shang-Ping

    2017-09-01

    Over the past six decades, the subtropical surface ocean has warmed at rates close to those of global mean surface ocean temperature except in western boundary current regions where the surface warming is locally enhanced by a factor of two. Changes in the subsurface ocean, however, remain unclear because of lack of data. Compiling historical temperature measurements--some available for the first time--here we show that the subtropical mode water has warmed over the past six decades in both the North Pacific and North Atlantic. The rate of the warming is twice as large in the mode waters than at the surface. Subtropical mode waters are important water masses of vertically uniform temperature that are a few hundred metres thick and distributed widely in the main thermocline of the subtropical oceans. The enhanced warming of subtropical mode waters can be traced back to the surface warming in the formation regions along the western boundary current extensions. Furthermore, we detect increased temperature stratification and decreased dissolved oxygen in the subtropical mode waters. The latter change has clear implications for predicting biogeochemical responses to climate warming.

  18. The role of South Pacific atmospheric variability in the development of different types of ENSO

    Science.gov (United States)

    You, Yujia; Furtado, Jason C.

    2017-07-01

    Recent advances in tropical Pacific climate variability have focused on understanding the development of El Niño-Southern Oscillation (ENSO) events, specifically the types or "flavors" of ENSO (i.e., central versus eastern Pacific events). While precursors to ENSO events exist, distinguishing the particular flavor of the expected ENSO event remains unresolved. This study offers a new look at ENSO predictability using South Pacific atmospheric variability during austral winter as an indicator. The positive phase of the leading mode of South Pacific sea level pressure variability, which we term the South Pacific Oscillation (SPO), exhibits a meridional dipole with with a(n) (anti)cyclonic anomaly dominating the subtropics (extratropics/high latitudes). Once energized, the cyclonic anomalies in the subtropical node of the SPO weaken the southeasterly trade winds and promote the charging of the eastern equatorial Pacific Ocean, giving rise to eastern Pacific ENSO events. Indeed, the type of ENSO event can be determined accurately using only the magnitude and phase of the SPO during austral winter as a predictor (17 out of 23 cases). The SPO may also play a role in explaining the asymmetry of warm and cold events. Collectively, our findings present a new perspective on ENSO-South Pacific interactions that can advance overall understanding of the ENSO system and enhance its predictability across multiple timescales.

  19. Pollutants in Plastics within the North Pacific Subtropical Gyre

    NARCIS (Netherlands)

    Chen, Qiqing; Reisser, Julia; Cunsolo, Serena; Kwadijk, Christiaan; Kotterman, M.J.J.; Proietti, Maira; Slat, Boyan; Ferrari, Francesco; Schwarz, Anna; Levivier, Aurore; Yin, Daqiang; Hollert, Henner; Koelmans, A.A.

    2018-01-01

    Here we report concentrations of pollutants in floating plastics from the North Pacific accumulation zone (NPAC). We compared chemical concentrations in plastics of different types and sizes, assessed ocean plastic potential risks using sediment quality criteria, and discussed the implications of

  20. Interannual Variability of Methane and Nitrous Oxide in the North Pacific Subtropical Gyre

    Science.gov (United States)

    Wilson, Samuel T.; Ferrón, Sara; Karl, David M.

    2017-10-01

    The temporal variability of two important greenhouse gases, methane (CH4) and nitrous oxide (N2O), is reported for the upper water column at Station ALOHA in the North Pacific Subtropical Gyre. Measured concentrations of N2O conform to predicted values with an increase in saturation during the summer period. In contrast, CH4 is less predictable and shows an approximate 2 year transition from a state of oversaturation in surface waters to equilibrium values in 2015, implying a change in net CH4 production. The decrease in CH4 followed on from fluctuations in phosphate concentrations supporting the hypothesized link between microbial metabolism of phosphorus and the global biogeochemical cycle of CH4. At this current time, future trends in the net CH4 production in the North Pacific Subtropical Gyre are uncertain and specifically whether the surface ocean will be a net source or sink for CH4.

  1. Environmental drivers of mesozooplankton biomass variability in the North Pacific Subtropical Gyre

    Science.gov (United States)

    Valencia, Bellineth; Landry, Michael R.; Décima, Moira; Hannides, Cecelia C. S.

    2016-12-01

    The environmental drivers of zooplankton variability are poorly explored for the central subtropical Pacific, where a direct bottom-up food-web connection is suggested by increasing trends in primary production and mesozooplankton biomass at station ALOHA (A Long-term Oligotrophic Habitat Assessment) over the past 20 years (1994-2013). Here we use generalized additive models (GAMs) to investigate how these trends relate to the major modes of North Pacific climate variability. A GAM based on monthly mean data explains 43% of the temporal variability in mesozooplankton biomass with significant influences from primary productivity (PP), sea surface temperature (SST), North Pacific Gyre Oscillation (NPGO), and El Niño. This result mainly reflects the seasonal plankton cycle at station ALOHA, in which increasing light and SST lead to enhanced nitrogen fixation, productivity, and zooplankton biomass during summertime. Based on annual mean data, GAMs for two variables suggest that PP and 3-4 year lagged NPGO individually account for 40% of zooplankton variability. The full annual mean GAM explains 70% of variability of zooplankton biomass with significant influences from PP, 4 year lagged NPGO, and 4 year lagged Pacific Decadal Oscillation (PDO). The NPGO affects wind stress, sea surface height, and subtropical gyre circulation and has been linked to mideuphotic zone anomalies in salinity and PP at station ALOHA. Our study broadens the known impact of this climate mode on plankton dynamics in the North Pacific. While lagged transport effects are also evident for subtropical waters, our study highlights a strong coupling between zooplankton fluctuations and PP, which differs from the transport-dominated climate influences that have been found for North Pacific boundary currents.

  2. Summer diatom blooms in the North Pacific subtropical gyre: 2008-2009.

    Directory of Open Access Journals (Sweden)

    Tracy A Villareal

    Full Text Available The summertime North Pacific subtropical gyre has widespread phytoplankton blooms between Hawaii and the subtropical front (∼30°N that appear as chlorophyll (chl increases in satellite ocean color data. Nitrogen-fixing diatom symbioses (diatom-diazotroph associations: DDAs often increase 10(2-10(3 fold in these blooms and contribute to elevated export flux. In 2008 and 2009, two cruises targeted satellite chlorophyll blooms to examine DDA species abundance, chlorophyll concentration, biogenic silica concentration, and hydrography. Generalized observations that DDA blooms occur when the mixed layer depth is 10 µm chl a fraction (∼40-90+% of total chl a. Integrated diatom abundance varied 10-fold over 10 µm size fraction, and increased up to 5-fold in the blooms. The two years differed in the magnitude of the surface chl a increase (2009>2008, the abundance of pennate diatoms within the bloom (2009>2008, and the substantially greater mixed layer depth in 2009. Only the 2009 bloom had sufficient chl a in the >10 µm fraction to produce the observed ocean color chl increase. Blooms had high spatial variability; ocean color images likely average over numerous small events over time and space scales that exceed the individual event scale. Summertime DDA export flux noted at the Hawaii time-series Sta. ALOHA is probably a generalized feature of the eastern N. Pacific north to the subtropical front.

  3. Pollutants in Plastics within the North Pacific Subtropical Gyre.

    Science.gov (United States)

    Chen, Qiqing; Reisser, Julia; Cunsolo, Serena; Kwadijk, Christiaan; Kotterman, Michiel; Proietti, Maira; Slat, Boyan; Ferrari, Francesco F; Schwarz, Anna; Levivier, Aurore; Yin, Daqiang; Hollert, Henner; Koelmans, Albert A

    2018-01-16

    Here we report concentrations of pollutants in floating plastics from the North Pacific accumulation zone (NPAC). We compared chemical concentrations in plastics of different types and sizes, assessed ocean plastic potential risks using sediment quality criteria, and discussed the implications of our findings for bioaccumulation. Our results suggest that at least a fraction of the NPAC plastics is not in equilibrium with the surrounding seawater. For instance, "hard plastic" samples had significantly higher PBDE concentrations than "nets and ropes" samples, and 29% of them had PBDE composition similar to a widely used flame-retardant mixture. Our findings indicate that NPAC plastics may pose a chemical risk to organisms as 84% of the samples had at least one chemical exceeding sediment threshold effect levels. Furthermore, our surface trawls collected more plastic than biomass (180 times on average), indicating that some NPAC organisms feeding upon floating particles may have plastic as a major component of their diets. If gradients for pollutant transfer from NPAC plastic to predators exist (as indicated by our fugacity ratio calculations), plastics may play a role in transferring chemicals to certain marine organisms.

  4. Hydrological implications of desertification: Degradation of South African semi-arid subtropical thicket

    NARCIS (Netherlands)

    Luijk, van G.; Cowling, R.M.; Riksen, M.J.P.M.; Glenday, J.

    2013-01-01

    Almost half of the 16,942 km2 of South Africa's subtropical thicket with a substantial Portulacaria afra (spekboom) component has been heavily degraded by domestic herbivores. The subtropical thicket biome is a drought-prone and water-stressed area, and many of the region's watersheds comprise of

  5. Storm Aerosol Environments and Aerosol Sources in Subtropical South America

    Science.gov (United States)

    Cancelada, M.; Salio, P. V.; Nesbitt, S. W.

    2016-12-01

    Several studies have shown a strong interaction in the subtropical area of Southeastern South America (SESA) between deep moist convection and the presence of the South American low level jet (SALLJ), which advects humidity and heat from tropical latitudes creating ideal conditions in the environment for convective activity. Moreover, the SALLJ is considered an important mechanism for transport of gases and particulate matter emitted in tropical South America. Biomass burning season associated with deforestation and land clearing for agricultural use is observed in these regions principally from August to October. Past studies have shown, through modeling and in-situ measurements, an increase in optical depth and Angstrom exponent during SALLJ events. Evidence of an increase in aerosol loading during burning biomass season, along with favorable conditions for deep moist convection activity, supports the hypothesis of an indirect effect from aerosols in convective development in SESA. The objective of this work is to characterize aerosol environments in SESA associated with the presence of mesoscale convective system development. High aerosol concentration events during biomass burning season from 2002 to 2015 were detected using corrected aerosol optical depth (CAOD) with 10-km horizontal resolution from Moderate Resolution Imaging Spectroradiometer (MODIS) Aerosol Products. Environmental variables from NCEP Climate Forecast System Reanalysis (CFSR) were examined to detect SALLJ events and deep moist convection development was observed through infrared channel from GOES. This combination of aerosol data and SALLJ presence determined a data-set for polluted and non-polluted environments. A remarkable correlation between higher values of CAOD in central Argentina and SALLJ was found. A case of study with evidence of SALLJ, high CAOD values and strong convection development was examined. A Weather Research and Forecasting (WRF) simulation has been performed in order

  6. The fate of a southwest Pacific bloom: gauging the impact of submesoscale vs. mesoscale circulation on biological gradients in the subtropics

    Science.gov (United States)

    de Verneil, Alain; Rousselet, Louise; Doglioli, Andrea M.; Petrenko, Anne A.; Moutin, Thierry

    2017-07-01

    The temporal evolution of a surface chlorophyll a bloom sampled in the western tropical South Pacific during the 2015 Oligotrophy to UlTra-oligotrophy PACific Experiment (OUTPACE) cruise is examined. This region is usually characterized by largely oligotrophic conditions, i.e. low concentrations of inorganic nutrients at the surface and deep chlorophyll a maxima. Therefore, the presence of a surface bloom represents a significant perturbation from the mean ecological state. Combining in situ and remote sensing datasets, we characterize both the bloom's biogeochemical properties and the physical circulation responsible for structuring it. Biogeochemical observations of the bloom document the bloom itself, a subsequent decrease of surface chlorophyll a, significantly reduced surface phosphate concentrations relative to subtropical gyre water farther east, and a physical decoupling of chlorophyll a from a deep nitracline. All these characteristics are consistent with nitrogen fixation occurring within the bloom. The physical data suggest surface mesoscale circulation is the primary mechanism driving the bloom's advection, whereas balanced motions expected at submesoscales provide little contribution to observed flow. Together, the data provide a narrative where subtropical gyre water can produce significant chlorophyll a concentrations at the surface that is stirred, deformed, and transported great distances by the mesoscale circulation. In this case, for the time period considered, the transport is in an easterly direction, contrary to both the large-scale and mean mesoscale flow. As a result, future studies concerning surface production in the region need to take into account the role complex mesoscale structures play in redistributing subtropical gyre water.

  7. Influence of the West Pacific subtropical high on surface ozone daily variability in summertime over eastern China

    Science.gov (United States)

    Zhao, Zijian; Wang, Yuxuan

    2017-12-01

    The West Pacific subtropical high (WPSH), as one of the most important components of the East Asian summer monsoon (EASM), is the key synoptic-scale circulation pattern influencing summertime precipitation and atmospheric conditions in China. Here we investigate the impacts of the WPSH on surface ozone daily variability over eastern China, using observations from recently established network of ozone monitors and meteorology reanalysis data during summer (June, July, August; JJA) 2014-2016 with a focus on 2014. An empirical orthogonal function (EOF) analysis of daily ozone variations reveals that the dominating eigenvector (EOF1), which contributes a quarter (25.2%) to the total variances, is a marked north-south contrast. This pattern is temporally well correlated (r = -0.66, p pattern showing the same north-south contrast (r = -0.86, p surface ozone daily variability in eastern China is linked with the variability of the WPSH intensity in that a stronger WPSH leads to a decrease of surface ozone over SC but an increase over NC and vice versa. This is because a stronger WPSH enhances southwesterly transport of moisture into SC, creating such conditions not conducive for ozone formation as higher RH, more cloudiness and precipitation, less UV radiation, and lower temperature. Meanwhile, as most of the rainfall due to the enhanced southwesterly transport of moisture occurs in SC, water vapor is largely depleted in the air masses transported towards NC, creating dry and sunny conditions over NC under a strong WPSH, thereby promoting ozone formation.

  8. Gooseneck barnacles (Lepas spp. ingest microplastic debris in the North Pacific Subtropical Gyre

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    Miriam C. Goldstein

    2013-10-01

    Full Text Available Substantial quantities of small plastic particles, termed “microplastic,” have been found in many areas of the world ocean, and have accumulated in particularly high densities on the surface of the subtropical gyres. While plastic debris has been documented on the surface of the North Pacific Subtropical Gyre (NPSG since the early 1970s, the ecological implications remain poorly understood. Organisms associated with floating objects, termed the “rafting assemblage,” are an important component of the NPSG ecosystem. These objects are often dominated by abundant and fast-growing gooseneck barnacles (Lepas spp., which predate on plankton and larval fishes at the sea surface. To assess the potential effects of microplastic on the rafting community, we examined the gastrointestinal tracts of 385 barnacles collected from the NPSG for evidence of plastic ingestion. We found that 33.5% of the barnacles had plastic particles present in their gastrointestinal tract, ranging from one plastic particle to a maximum of 30 particles. Particle ingestion was positively correlated to capitulum length, and no blockage of the stomach or intestines was observed. The majority of ingested plastic was polyethylene, with polypropylene and polystyrene also present. Our results suggest that barnacle ingestion of microplastic is relatively common, with unknown trophic impacts on the rafting community and the NPSG ecosystem.

  9. Gooseneck barnacles (Lepas spp.) ingest microplastic debris in the North Pacific Subtropical Gyre.

    Science.gov (United States)

    Goldstein, Miriam C; Goodwin, Deborah S

    2013-01-01

    Substantial quantities of small plastic particles, termed "microplastic," have been found in many areas of the world ocean, and have accumulated in particularly high densities on the surface of the subtropical gyres. While plastic debris has been documented on the surface of the North Pacific Subtropical Gyre (NPSG) since the early 1970s, the ecological implications remain poorly understood. Organisms associated with floating objects, termed the "rafting assemblage," are an important component of the NPSG ecosystem. These objects are often dominated by abundant and fast-growing gooseneck barnacles (Lepas spp.), which predate on plankton and larval fishes at the sea surface. To assess the potential effects of microplastic on the rafting community, we examined the gastrointestinal tracts of 385 barnacles collected from the NPSG for evidence of plastic ingestion. We found that 33.5% of the barnacles had plastic particles present in their gastrointestinal tract, ranging from one plastic particle to a maximum of 30 particles. Particle ingestion was positively correlated to capitulum length, and no blockage of the stomach or intestines was observed. The majority of ingested plastic was polyethylene, with polypropylene and polystyrene also present. Our results suggest that barnacle ingestion of microplastic is relatively common, with unknown trophic impacts on the rafting community and the NPSG ecosystem.

  10. Gooseneck barnacles (Lepas spp.) ingest microplastic debris in the North Pacific Subtropical Gyre

    Science.gov (United States)

    Goodwin, Deborah S.

    2013-01-01

    Substantial quantities of small plastic particles, termed “microplastic,” have been found in many areas of the world ocean, and have accumulated in particularly high densities on the surface of the subtropical gyres. While plastic debris has been documented on the surface of the North Pacific Subtropical Gyre (NPSG) since the early 1970s, the ecological implications remain poorly understood. Organisms associated with floating objects, termed the “rafting assemblage,” are an important component of the NPSG ecosystem. These objects are often dominated by abundant and fast-growing gooseneck barnacles (Lepas spp.), which predate on plankton and larval fishes at the sea surface. To assess the potential effects of microplastic on the rafting community, we examined the gastrointestinal tracts of 385 barnacles collected from the NPSG for evidence of plastic ingestion. We found that 33.5% of the barnacles had plastic particles present in their gastrointestinal tract, ranging from one plastic particle to a maximum of 30 particles. Particle ingestion was positively correlated to capitulum length, and no blockage of the stomach or intestines was observed. The majority of ingested plastic was polyethylene, with polypropylene and polystyrene also present. Our results suggest that barnacle ingestion of microplastic is relatively common, with unknown trophic impacts on the rafting community and the NPSG ecosystem. PMID:24167779

  11. Atmospheric Mercury Deposition to a Remote Islet in the Subtropical Northwest Pacific Ocean

    Science.gov (United States)

    Sheu, G.; Lin, N.

    2013-12-01

    Thirty-four weekly rainwater samples were collected in 2009 at Pengjiayu, a remote islet in the subtropical Northwest (NW) Pacific Ocean with an area of 1.14 km^2, to study the distribution of rainwater mercury (Hg) concentrations and associated wet deposition fluxes. This is the first study concerning wet Hg deposition to the subtropical NW Pacific Ocean downwind of the East Asian continent, which is the major source region for Hg emissions worldwide. Sample Hg concentrations ranged from 2.25 to 22.33 ng L^-1, with a volume-weighted mean (VWM) concentration of 8.85 ng L^-1. The annual wet Hg deposition flux was 10.18 μg m^-2, about 2.5 times the fluxes measured at sites on the Pacific coast of the USA, supporting the hypothesis that deposition is higher in the western than in the eastern Pacific. Seasonal VWM concentrations were 7.23, 11.58, 7.82, and 9.84 ng L^-1, whereas seasonal wet deposition fluxes were 2.14, 3.45, 2.38, and 2.21 μg m^-2, for spring, summer, fall and winter, respectively. Higher summer wet Hg deposition was a function of both higher rainwater Hg concentration and greater rainfall. The seasonal pattern of rainwater Hg concentrations was the opposite of the general seasonal pattern of the East Asian air pollutant export. Since there is no significant anthropogenic Hg emission source on the islet of Pengjiayu, the observed high summertime rainwater Hg concentration hints at the importance of Hg(0) oxidation and/or scavenging of upper-altitude reactive gaseous Hg (RGM) by deep convection. Direct anthropogenic RGM emissions from the East Asian continent may not contribute significantly to the rainwater Hg concentrations, but anthropogenic Hg(0) emissions could be transported to the upper troposphere or marine boundary layer where they can be oxidized to produce RGM, which will then be effectively scavenged by cloud water and rainwater.

  12. Modelling spatial heterogeneity of phytoplankton in Lake Mangueira, a large shallow subtropical lake in South Brazil

    NARCIS (Netherlands)

    Fragoso, C.R.; Motta Marques, D.M.L.; Collischonn, W.; Tucci, C.E.M.; Nes, van E.H.

    2008-01-01

    We present a model describing phytoplankton growth in Lake Mangueira, a large subtropical lake in the Taim Hydrological System in South Brazil (817 km2, average depth 2 m). The horizontal 2D model consists of three modules: (a) a detailed hydrodynamic module for shallow water, which deals with

  13. Meteorology of the Southern Global Plume: African and South American Fires Pollute the South Pacific

    Science.gov (United States)

    Guo, Z.; Chatfield, R. B.

    1999-01-01

    An immense global plume of CO meanders widely around the world in the Southern Hemisphere. It arises over Southern America and Africa and flows eastward. The first emissions are in tropical Brazil, and the plume circulates around the world to South America again. The plume was largely unexpected until there were aircraft studies made in NASA's Pacific Exploratory Mission - Tropics (Part A). This paper describes the meteorology of the Global Plume, as our simulation, with a synoptic model adapted to global transport, reveals it with a tracer-CO simulation. The observations and their simulation require a particular set of conditions of pollutant accumulation, cumulonimbus venting with required strengths at a narrow range of altitude. Additionally, a particular subtropical conduction region, over the Indian Ocean, Australia, and the westeRNmost South Pacific, relatively free of storms, appears to be a key part of the mechanism. These conclusions are the results of a synoptic reconstruction of the PEMT-A period, September- October, 1996.

  14. The fate of a southwest Pacific bloom: gauging the impact of submesoscale vs. mesoscale circulation on biological gradients in the subtropics

    Directory of Open Access Journals (Sweden)

    A. de Verneil

    2017-07-01

    Full Text Available The temporal evolution of a surface chlorophyll a bloom sampled in the western tropical South Pacific during the 2015 Oligotrophy to UlTra-oligotrophy PACific Experiment (OUTPACE cruise is examined. This region is usually characterized by largely oligotrophic conditions, i.e. low concentrations of inorganic nutrients at the surface and deep chlorophyll a maxima. Therefore, the presence of a surface bloom represents a significant perturbation from the mean ecological state. Combining in situ and remote sensing datasets, we characterize both the bloom's biogeochemical properties and the physical circulation responsible for structuring it. Biogeochemical observations of the bloom document the bloom itself, a subsequent decrease of surface chlorophyll a, significantly reduced surface phosphate concentrations relative to subtropical gyre water farther east, and a physical decoupling of chlorophyll a from a deep nitracline. All these characteristics are consistent with nitrogen fixation occurring within the bloom. The physical data suggest surface mesoscale circulation is the primary mechanism driving the bloom's advection, whereas balanced motions expected at submesoscales provide little contribution to observed flow. Together, the data provide a narrative where subtropical gyre water can produce significant chlorophyll a concentrations at the surface that is stirred, deformed, and transported great distances by the mesoscale circulation. In this case, for the time period considered, the transport is in an easterly direction, contrary to both the large-scale and mean mesoscale flow. As a result, future studies concerning surface production in the region need to take into account the role complex mesoscale structures play in redistributing subtropical gyre water.

  15. Large scale features associated with strong frontogenesis in equivalent potential temperature in the South American subtropics east of the Andes

    Directory of Open Access Journals (Sweden)

    J. M. Arraut

    2009-10-01

    Full Text Available South American subtropics east of the Andes exhibit a region of intense climatological frontogenesis in equivalent potential temperature (EPT in the December to March season, mostly produced by deformation of the wind field. The goal of this paper is to investigate the large scale features associated with intense and weak frontogenesis by deformation (FGD in EPT in the region where it attains its climatological maximum. This can be approximately delimited by 32–42° S and 66–69° W, which is small enough as to contain only one synoptic perturbation at a time. The spatial average of the positive values of frontogenesis at 850 hPa over the whole region (DFG+ is used to represent the strength of the perturbation. ECMWF ERA-40 reanalysis data set is used to calculate DFG+ at six hour intervals for 21 seasons (1981–2002. Compositing analysis is carried out for strong (above the 0.75 quantile and weak (below the 0.25 quantile events. For strong events the geopotential field at 850 hPa exhibits the North Argentinean Low (NAL, a transient trough and the Low Pressure Tongue East of the Andes (LPT. Upon comparison with the composite field of FGD it can be observed that FGD exhibits a strong maximum over the Argentinean Col (AC which separates the NAL and the trough. These features are absent in the weak frontogenesis composite, which exhibits a stronger South Pacific Subtropical High close to the continent. At 250 hPa the strong FGD composite exhibits a trough over the Andes with a wind speed maximum to its east. Both of these features are associated with the deepening of the NAL in the literature. These are not present in the weak FGD composites. Strong events show an intense quasi meridional corridor of water vapor transport from the Amazon to the subtropics that encounters westerly flow in the neighborhood of the AC. This is absent in weak events. A preliminary analysis of precipitation is carried out using the GPCP daily data set. An intense

  16. Evolution of the North Pacific Subtropical Mode Water in Anticyclonic Eddies

    Science.gov (United States)

    Xu, Lixiao; Xie, Shang-Ping; Liu, Qinyu; Liu, Cong; Li, Peiliang; Lin, Xiaopei

    2017-12-01

    Anticyclonic eddies (AEs) trap and transport the North Pacific subtropical mode water (STMW), but the evolution of the STMW trapped in AEs has not been fully studied due to the lack of eddy-tracking subsurface observations. Here we analyze profiles from special-designed Argo floats that follow two STMW-trapping AEs for more than a year. The enhanced daily sampling by these Argo floats swirling around the eddies enables an unprecedented investigation into the structure and evolution of the trapped STMW. In the AEs, the upper (lower) thermocline domes up (concaves downward), and this lens-shaped double thermocline encompasses the thick STMW within the eddy core. The lighter STMW (25.0 ˜ 25.2 σθ) trapped in AEs dissipates quickly after the formation in winter because of the deepening seasonal thermocline, but the denser STMW (25.2 ˜ 25.4 σθ) remains largely unchanged except when the AE passes across the Izu Ridge. The enhanced diapycnal mixing over the ridge weakens the denser STMW appreciably. While many AEs decay upon hitting the ridge, some pass through a bathymetric gap between the Hachijojima and Bonin Islands, forming a cross-ridge pathway for STMW transport. By contrast, the North Pacific Intermediate Water (NPIW) underneath is deeper than the eddy trapping depth (600 m), and hence left behind east of the Izu Ridge. In Argo climatology, the shallow STMW (< 400 m) intrudes through the gap westward because of the eddy transport, while the NPIW (800 m) is blocked by the Izu Ridge.

  17. Arcane epipelagic fishes of the subtropical North Pacific and factors associated with their distribution

    Science.gov (United States)

    McKinnell, Skip; Seki, Michael P.

    2017-01-01

    In 1992, a moratorium was declared by the United Nations General Assembly to end the practice of large-scale pelagic driftnet fishing. During two years leading up to the moratorium, three scientific research and fishery observer programs involving Canada, Japan, Korea, China-Taipei and the United States had collected significant amounts of information about the distribution and abundance of the epipelagic fauna in the subtropical North Pacific Ocean. The pan-regional distributions of the fishes in 1990 and 1991, most of which were taken as bycatch in 9910 fishing operations (357,150 km of driftnet) are described. More species were observed per fishing operation in 1991 than in 1990. Principal coordinate analysis of the incidence of the commonly caught fish species was used to show that, except for an anomaly in the region of the Shatsky Rise (165°E), the composition of the catch changed from the coast of Japan across more than 6000 km to the eastern boundary of the fishery (145°W). The analysis suggested that the fish species composition changed rather little with increasing latitude within the southern part of the domain (25-35°N), before changing more rapidly north of the Kuroshio Extension region to a more subarctic, transition zone fauna.

  18. Export stoichiometry and migrant-mediated flux of phosphorus in the North Pacific Subtropical Gyre

    Science.gov (United States)

    Hannides, Cecelia C. S.; Landry, Michael R.; Benitez-Nelson, Claudia R.; Styles, Renée M.; Montoya, Joseph P.; Karl, David M.

    2009-01-01

    Export processes play a major role in regulating global marine primary production by reducing the efficiency of nutrient cycling and turnover in surface waters. Most studies of euphotic zone export focus on passive fluxes, that is, sinking particles. However, active transport, the vertical transfer of material by migrating zooplankton, can also be an important component of carbon (C) and nitrogen (N) removal from the surface ocean. Here we demonstrate that active transport is an especially important mechanism for phosphorus (P) removal from the euphotic zone at Station ALOHA (Hawaii Ocean Time-series program; 22°45'N, 158°W), a P-stressed site in the North Pacific Subtropical Gyre. Migrant excretions in this region are P-rich (C 51:N 12:P 1) relative to sinking particles (C 250:N 31:P 1), and migrant-mediated P fluxes are almost equal in magnitude (82%) to P fluxes from sediment traps. Migrant zooplankton biomass and therefore the importance of this P removal pathway relative to sinking fluxes has increased significantly over the past 12 years, suggesting that active transport may be a major driving force for enhanced P-limitation of biological production in the NPSG. We further assess the C:N:P composition of zooplankton size fractions at Station ALOHA (C 88:N 18:P 1, on average) and discuss migrant-mediated P export in light of the balance between zooplankton and suspended particle stoichiometries. We conclude that, because active transport is such a large component of the total P flux and significantly impacts ecosystem stoichiometry, export processes involving migrant zooplankton must be included in large-scale efforts to understand biogeochemical cycles.

  19. Microbial community structure and function on sinking particles in the North Pacific Subtropical Gyre

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    Kristina M. Fontanez

    2015-05-01

    Full Text Available Sinking particles mediate the transport of carbon and energy to the deep-sea, yet the specific microbes associated with sedimenting particles in the ocean’s interior remain largely uncharacterized. In this study, we used particle interceptor traps (PITs to assess the nature of particle-associated microbial communities collected at a variety of depths in the North Pacific Subtropical Gyre. Comparative metagenomics was used to assess differences in microbial taxa and functional gene repertoires in PITs containing a preservative (poisoned traps compared to preservative-free traps where growth was allowed to continue in situ (live traps. Live trap microbial communities shared taxonomic and functional similarities with bacteria previously reported to be enriched in dissolved organic matter (DOM microcosms (e.g., Alteromonas and Methylophaga, in addition to other particle and eukaryote-associated bacteria (e.g., Flavobacteriales and Pseudoalteromonas. Poisoned trap microbial assemblages were enriched in Vibrio and Campylobacterales likely associated with eukaryotic surfaces and intestinal tracts as symbionts, pathogens or saprophytes. The functional gene content of microbial assemblages in poisoned traps included a variety of genes involved in virulence, anaerobic metabolism, attachment to chitinaceaous surfaces, and chitin degradation. The presence of chitinaceaous surfaces was also accompanied by the co-existence of bacteria which encoded the capacity to attach to, transport and metabolize chitin and its derivatives. Distinctly different microbial assemblages predominated in live traps, which were largely represented by copiotrophs and eukaryote-associated bacterial communities. These data indicate the central role of eukaryotic taxa in structuring sinking particle microbial assemblages, as well as the rapid responses of indigenous microbial species in the degradation of marine particulate organic matter in situ in the ocean’s interior.

  20. Variability in photosynthetic production of dissolved and particulate organic carbon in the North Pacific Subtropical Gyre

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    Donn A. Viviani

    2015-10-01

    Full Text Available The partitioning of photosynthetically-derived organic carbon between particulate and dissolved phases has important implications for marine carbon cycling. In this study we utilized 14C-bicarbonate assimilation to quantify rates of photosynthetic production of both particulate and dissolved organic carbon (DOC at Station ALOHA (22˚45’N, 158˚W in the North Pacific Subtropical Gyre (NPSG. At near-monthly time scales over ~5 years, we examined retention of 14C-labeled organic matter by both glass fiber filters and 0.2 µm pore size polycarbonate membrane filters that are commonly used for measurements of 14C-based plankton productivity. Use of polycarbonate filters resulted in significantly lower (averaging 60% estimates of 14C-production compared to glass fiber filters. Coincident measurements of chlorophyll a concentrations from both 0.2 µm polycarbonate and glass fiber filters were not significantly different, suggesting the differences in 14C-productivity between these filter-types did not derive from differences in retention of photosynthetic biomass by these filters. Moreover, consistent with previous studies, results from experiments aimed at quantifying retention of organic matter by these filters suggested the difference between these two types of filters resulted from retention of DOC by glass fiber filters. We also quantified rates of 14C-DOC production to evaluate the partitioning of photosynthetic production between dissolved and particulate phases over daily to monthly time scales in this ecosystem. Unlike the strong depth-dependence observed in measurements of particulate organic carbon production, measured rates of 14C-DOC demonstrated no clear depth-dependence. On average, depth-integrated (0-75 m rates of 14C-DOC production rates were equivalent to 18 ± 10% of the total (particulate and dissolved productivity. Our findings indicate that in this oligotrophic ecosystem, rates of dissolved and particulate production can be

  1. Phenology of particle size distributions and primary productivity in the North Pacific subtropical gyre (Station ALOHA)

    Science.gov (United States)

    White, Angelicque E.; Letelier, Ricardo M.; Whitmire, Amanda L.; Barone, Benedetto; Bidigare, Robert R.; Church, Matthew J.; Karl, David M.

    2015-11-01

    The particle size distribution (PSD) is a critical aspect of the oceanic ecosystem. Local variability in the PSD can be indicative of shifts in microbial community structure and reveal patterns in cell growth and loss. The PSD also plays a central role in particle export by influencing settling speed. Satellite-based models of primary productivity (PP) often rely on aspects of photophysiology that are directly related to community size structure. In an effort to better understand how variability in particle size relates to PP in an oligotrophic ecosystem, we collected laser diffraction-based depth profiles of the PSD and pigment-based classifications of phytoplankton functional types (PFTs) on an approximately monthly basis at the Hawaii Ocean Time-series Station ALOHA, in the North Pacific subtropical gyre. We found a relatively stable PSD in the upper water column. However, clear seasonality is apparent in the vertical distribution of distinct particle size classes. Neither laser diffraction-based estimations of relative particle size nor pigment-based PFTs was found to be significantly related to the rate of 14C-based PP in the light-saturated upper euphotic zone. This finding indicates that satellite retrievals of particle size, based on particle scattering or ocean color would not improve parameterizations of present-day bio-optical PP models for this region. However, at depths of 100-125 m where irradiance exerts strong control on PP, we do observe a significant linear relationship between PP and the estimated carbon content of 2-20 μm particles.

  2. Particle distributions and dynamics in the euphotic zone of the North Pacific Subtropical Gyre

    Science.gov (United States)

    Barone, Benedetto; Bidigare, Robert R.; Church, Matthew J.; Karl, David M.; Letelier, Ricardo M.; White, Angelicque E.

    2015-05-01

    During the summer of 2012, we used laser diffractometry to investigate the temporal and vertical variability of the particle size spectrum (1.25-100 µm in equivalent diameter) in the euphotic zone of the North Pacific Subtropical Gyre. Particles measured with this optical method accounted for ˜40% of the particulate carbon stocks (<202 µm) in the upper euphotic zone (25-75 m), as estimated using an empirical formula to transform particle volume to carbon concentrations. Over the entire vertical layer considered (20-180 m), the largest contribution to particle volume corresponded to particles between 3 and 10 µm in diameter. Although the exponent of a power law parameterization suggested that larger particles had a lower relative abundance than in other regions of the global ocean, this parameter and hence conclusions about relative particle abundance are sensitive to the shape of the size distribution and to the curve fitting method. Results on the vertical distribution of particles indicate that different size fractions varied independently with depth. Particles between 1.25 and 2 µm reached maximal abundances coincident with the depth of the chlorophyll a maximum (averaging 121 ± 10 m), where eukaryotic phytoplankton abundances increased. In contrast, particles between 2 and 20 µm tended to accumulate just below the base of the mixed layer (41 ± 14 m). Variability in particle size tracked changes in the abundance of specific photoautotrophic organisms (measured with flow cytometry and pigment concentration), suggesting that phytoplankton population dynamics are an important control of the spatiotemporal variability in particle concentration in this ecosystem.

  3. Using eddy geopotential height to measure the western North Pacific subtropical high in a warming climate

    Science.gov (United States)

    He, Chao; Lin, Ailan; Gu, Dejun; Li, Chunhui; Zheng, Bin; Wu, Bo; Zhou, Tianjun

    2018-01-01

    The western North Pacific subtropical high (WNPSH) is crucial to the East Asian summer climate, and geopotential height ( H) is widely used to measure the WPNSH. However, a rapidly rising trend of H in the future is projected by the models from the Coupled Model Intercomparison Project Phase 5 (CMIP5). Diagnoses based on the hypsometric equation suggest that more than 80% of the rise in H are attributable to zonal uniform warming. Because circulation is determined by the gradient of H rather than its absolute magnitude, the spatially uniform rising trend of H gives rise to difficulties when measuring the WNPSH with H. These difficulties include an invalid western boundary of WNPSH in the future and spurious information regarding long-term trends and interannual variability of WNPSH. Using CMIP5 model simulations and reanalysis data, the applicability of a metric based on eddy geopotential height ( H e ) to the warming climate is investigated. The results show that the H e metric outperforms the H metric under warming climate conditions. First, the mean state rainfall- H e relationship is more robust than the rainfall- H relationship. Second, the area, intensity, and western boundary indices of WNPSH can be effectively defined by the H e = 0-m contour in future warming climate scenarios without spurious trends. Third, the interannual variability of East Asian summer rainfall is more closely related to the H e -based WNPSH indices. We recommend that the H e metric be adopted as an operational metric on the WNPSH under the current warming climate.

  4. Autonomous Sampling of Remote Phytoplankton Blooms in the North Pacific Subtropical Gyre (July-Aug. 2015).

    Science.gov (United States)

    Anderson, E. E.; Wilson, C.; Villareal, T. A.

    2016-12-01

    Satellite ocean color data regularly reveals the existence of large (103 km2) phytoplankton blooms in the North Pacific Ocean that can persist for weeks to months and are often associated with N2 fixing diatom symbioses. The basin size and inability to accurately forecast these blooms makes sampling these events difficult outside of the time series at Station ALOHA. We used an autonomous Wave Glider surface vehicle (Honey Badger) to conduct a large regional survey well north of HI to examine bloom composition and key species distribution. Honey Badger was equipped with a gpCTD, downward looking camera, 2 C3 fluorometers, wind and wave sensors, a Turner Designs' Phytoflash, and a Sequoia Scientific LISST-Holo for imaging cells. Most of the data collected was available in near-real time through NOAA's ERDDAP data server. The 159 day mission began 1 June 2015 and covered 6800 km. From 1 July 2015 to 31 August 2015, Honey Badger transited from low levels of chlorophyll-a (chl) (0.06±0.01 mg m-3), through a mesoscale­ bloom, and then into a broad regional chl increase (0.08±0.01 mg m-3) as noted by the AQUA MODIS satellite. Phytoplankton cell counts (> 14,000 Hemiaulus cells L-1) and increased nocturnal Fv:Fm yields (maximum > 0.61) were concurrent with the 0.1 µg Chl L-1 bloom. A separate bloom of the Rhizosolenia-Richelia symbiosis was noted (> 3,000 Rhizosolenia-Richelia cells L-1) within a smaller, short-lived bloom with a biovolume 2.1 times higher than the rest of the southern transect. The broad regional chl increase in the southern leg of the transit was concurrent with a sustained Hemiaulus increase to 102 cells L-1. Diel patterns in Fv:Fm did not suggest Fe limitation anywhere in the transect. Elevated yields were found only in the diatom increases. Honey Badger and the instruments it carried were useful tools for the investigation of remote bloom dynamics in the Eastern North Pacific Subtropical Gyre.

  5. Observation of Subtropical Mode Water in the South Atlantic from Argo data

    Science.gov (United States)

    Sato, Olga; Polito, Paulo

    2013-04-01

    Subtropical mode waters in the South Atlantic ocean are detected using temperature (T) and salinity (S) profiles obtained by Argo floats. Mode waters are characterized as a large volume of water with a very narrow TS variation. Marked by low stratification within its extent, these water masses can be identified by highly homogeneous TS values, both horizontally and vertically. A potential vorticity minimum is generally used to track the mode water because it is a conservative property. Variations in the rate of formation of mode waters are connected to fluctuations in the air-sea interaction processes, including heat and moisture fluxes but also changes in the subtropical gyre circulation. Net heat flux, evaporation and precipitation rates are estimated from a combination of satellite data to correlate them with the regions of ventilation processes. The moisture flux (E-P) estimated from satellite data shows increasing (decreasing) trends right over the regions where the salinity increases (decreases) in the western South Atlantic between 2003 and 2012. The analysis of Argo data profiles and reanalysis models (GODAS and SODA) allows us to investigate the variability of the parameters in the ocean interior. Reanalysis models show more frequent and intense southward excursions of the Brazil Current towards the Brazil-Malvinas Confluence region from 1985 to 2012, contributing to increase the rate of Subtropical Mode Water formation.

  6. Gooseneck barnacles (Lepas spp.) ingest microplastic debris in the North Pacific Subtropical Gyre

    National Research Council Canada - National Science Library

    Goldstein, Miriam C; Goodwin, Deborah S

    2013-01-01

    Substantial quantities of small plastic particles, termed "microplastic," have been found in many areas of the world ocean, and have accumulated in particularly high densities on the surface of the subtropical gyres...

  7. Summer phytoplankton blooms in the oligotrophic North Pacific Subtropical Gyre: Historical perspective and recent observations

    Science.gov (United States)

    Dore, John E.; Letelier, Ricardo M.; Church, Matthew J.; Lukas, Roger; Karl, David M.

    2008-01-01

    The export of organic matter from the oceanic euphotic zone is a critical process in the global biogeochemical cycling of bioelements (C, N, P, Si). Much of this export occurs in the form of sinking particles, which rain down into the unlit waters of the deep sea. Classical models of oceanic production and export balance this gravitational loss of particulate bioelements with an upward flux of dissolved nutrients, and they describe reasonably well those areas of the ocean where deep winter mixing occurs. The surface waters of the North Pacific Subtropical Gyre (NPSG), however, are strongly stratified and chronically nutrient-depleted, especially in summer. Nevertheless, there is ample evidence that blooms of phytoplankton and subsequent pulses of particle export occur during the height of summer stratification in these waters, especially to the northeast of the Hawaiian Islands. These blooms impact regional bioelemental cycling and act as a food source to the deep-sea benthos. We review here numerous published observations of these events in the NPSG, and present new data collected at Station ALOHA (22.75°N, 158°W) during the first 176 cruises of the Hawaii Ocean Time-series program (1988-2005), along with results from transect cruises conducted in the region in 1996 and 2005. We suggest that the summer phytoplankton bloom can be considered a frequent, perhaps annual feature in the northeastern NPSG, and that its perceived stochastic nature is a manifestation of chronic undersampling in time and space. The bloom is typically dominated by only a few genera of large diatoms and the cyanobacterium Trichodesmium. It appears to be consistently supported by dinitrogen fixation, but the fate of the organic matter produced during the summer depends critically on the species composition of the responsible diazotrophs. We estimate that the summer bloom is responsible for up to 38% of N 2 fixation and up to 18% of N-based new production annually at Station ALOHA. We

  8. Differential assimilation of inorganic carbon and leucine by Prochlorococcus in the oligotrophic North Pacific Subtropical Gyre

    Directory of Open Access Journals (Sweden)

    Karin M. Björkman

    2015-12-01

    Full Text Available The light effect on photoheterotrophic processes in Prochlorococcus, and primary and bacterial productivity in the oligotrophic North Pacific Subtropical Gyre was investigated using 14C-bicarbonate and 3H-leucine. Light and dark incubation experiments were conducted in situ throughout the euphotic zone (0-175 m on nine expeditions to Station ALOHA over a three-year period. Photosynthetrons were also used to elucidate rate responses in leucine and inorganic carbon assimilation as a function of light intensity. Taxonomic group and cell-specific rates were assessed using flow cytometric sorting. The light:dark assimilation rate ratios of leucine in the top 150 m were ~7:1 for Prochlorococcus, whereas the light:dark ratio for the non-pigmented bacteria was not significant different from 1:1. Prochlorococcus assimilated leucine in the dark at per cell rates similar to the non-pigmented bacteria, with a contribution to the total community bacterial production, integrated over the euphotic zone, of approximately 20% in the dark and 60% in the light. Depth-resolved primary productivity and leucine incorporation showed that the ratio of Prochlorococcus leucine:primary production peaked at 100 m then declined steeply below the deep chlorophyll maximum (DCM. The photosynthetron experiments revealed that, for Prochlorococcus at the DCM, the saturating irradiance (Ek for leucine incorporation was reached at approximately half the light intensity required for light saturation of 14C-bicarbonate assimilation. Additionally, high and low red fluorescing Prochlorococcus populations (HRF and LRF, co-occurring at the DCM, had similar Ek values for their respective substrates, however, maximum assimilation rates, for both leucine and inorganic carbon, were two times greater for HRF cells. Our results show that Prochlorococcus contributes significantly to bacterial production estimates using 3H-leucine, whether or not the incubations are conducted in the dark or

  9. Regional variations of heavy metal concentrations in tissues of barnacles from the subtropical Pacific Coast of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Paez-Osuna, F.; Bojorquez-Leyva, H.; Ruelas-Inzunza, J. [Universidad Nacional Autonoma de Mexico, Mazatlan (Mexico)

    1999-07-01

    Concentrations of Cd, Cu, Cr, Fe, Mn, Ni, Ag, Pb, and Zn in soft and hard tissues of barnacles from eight sampling sites in six harbors on the subtropical Pacific Coast of Mexico were determined by atomic absorption spectrophotometry. Some inter-regional differences in metal concentrations, especially concerning Zn, Mn, Fe, Cd, and Pb, were identified. The lowest concentrations of Cu, Cr, Fe, and Ag were observed in the barnacle populations from Ceuta Lagoon, an uncontaminated site with rural agriculture and semi-intensive shrimp farms in the surroundings. Conversely, the highest concentrations of: (1) Zn, Cu, and Ag were found in the soft tissues of Balanus eburneus from Mazatlan piers; (2) Pb, Ni, and Cd in the soft tissue of Megabalanus coccopoma from Puerto Vallarta; (3) Fe in the hard tissue of Balanus sp. from Guaymas Harbour; and (4) Mn in the hard tissue of M. coccopoma from Mazatlan Harbour. Inter-comparison of the present data indicates that the soft (mainly Cd, Cu, Pb, and Zn) and the hard (mainly for Fe and Mn) tissues are useful in detecting areas of selected metallic contaminants. Barnacles such as B. eburneus, M. coccopoma, and Fistulobalanus dentivarians appear to be convenient biomonitors for identification of coastal waters exposed to Cd, Pb, Cu, Zn, Ni, Mn, Fe, and Ag in the American region of the subtropical Pacific.

  10. Approach for estimating the dynamic physical thresholds of phytoplankton production and biomass in the tropical-subtropical Pacific Ocean

    Science.gov (United States)

    Gómez-Ocampo, E.; Gaxiola-Castro, G.; Durazo, Reginaldo

    2017-06-01

    Threshold is defined as the point where small changes in an environmental driver produce large responses in the ecosystem. Generalized additive models (GAMs) were used to estimate the thresholds and contribution of key dynamic physical variables in terms of phytoplankton production and variations in biomass in the tropical-subtropical Pacific Ocean off Mexico. The statistical approach used here showed that thresholds were shallower for primary production than for phytoplankton biomass (pycnocline Ekman pumping (ADT 0 cm d-1 versus ADT 4 cm d-1). The relatively high productivity on seasonal (spring) and interannual (La Niña 2008) scales was linked to low ADT (45-60 cm) and shallow pycnocline depth (9-68 m) and mixed layer (8-40 m). Statistical estimations from satellite data indicated that the contributions of ocean circulation to phytoplankton variability were 18% (for phytoplankton biomass) and 46% (for phytoplankton production). Although the statistical contribution of models constructed with in situ integrated chlorophyll a and primary production data was lower than the one obtained with satellite data (11%), the fits were better for the former, based on the residual distribution. The results reported here suggest that estimated thresholds may reliably explain the spatial-temporal variations of phytoplankton in the tropical-subtropical Pacific Ocean off the coast of Mexico.

  11. Introduced Pacific oysters Crassostrea gigas in South Africa ...

    African Journals Online (AJOL)

    Introduced Pacific oysters Crassostrea gigas in South Africa: demographic change, genetic diversity and body condition. ... Given the species' considerable socio-economic importance, estuarine and coastal surveillance coupled with aquaculture zoning are required to integrate biodiversity and food security considerations.

  12. Gridded bathymetry of Tutuila Island, American Samoa, South Pacific

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (5 m cell size) bathymetry of the shelf and slope environments of Tutuila Island, American Samoa, South Pacific. Almost complete bottom coverage was achieved...

  13. The South Pacific Agenda: A Framework for ASEAN Participation

    Science.gov (United States)

    1989-03-31

    Nuclear-Free Zone. Following the endorsement by thirteen members of the SPF in August 1985 in Rarotonga , Cook Islands , the South Pacific Nuclear-Free...big powers as well as those of the smaller states in the region. The security and economic concerns of the island nations themselves will also be...purpose of this study is to propose the contribution that ASEAN, especially Singapore, can make to assist in bringing the South Pacific islands into

  14. Importance of the Viral Shunt in Nitrogen Cycling in Synechococcus Spp. Growth in Subtropical Western Pacific Coastal Waters

    Directory of Open Access Journals (Sweden)

    An-Yi Tsai

    2014-01-01

    Full Text Available Viruses play an important role in aquatic environments in bacteria and phytoplankton mortality and also in carbon and nutrient recycling through the lysis of living cells. However, the effects of nitrogen regenerated by viral lysis on the growth of picophytoplankton are rarely studied. This study investigated whether the presence of viruses has a positive effect on the daytime frequency of cell division in Synechococcus spp. in the coastal waters of the western subtropical Pacific Ocean. Using cell incubation with natural viral loads and reduced virus treatments, we characterized the abundance and frequency of cell division in Synechococcus spp. over time. Our results clearly showed that during the daytime as much as 30% of Synechococcus spp. were dividing in natural virus-containing samples, a proportion six times that found in the virus-diluted treatment groups (5%. These results suggest that viruses can exert significant effects on nutrient regeneration, enhancing daytime cell division rates in Synechococcus spp.

  15. Community-based materials development: report from the South Pacific.

    Science.gov (United States)

    Goodwillie, D

    1992-01-01

    In the early 1980s, women in the South Pacific region called for culturally sensitive, attractive nutrition teaching aids. A set of 13 nutrition education books was produced dealing with food and diseases, food preservation, fitness, gardening, budgeting, developing training materials, and individual food needs of family members. A decision was made to expand the writing group to health educators, home economics teachers, agriculture workers and community workers. Over 70 Pacific Islanders from 19 countries were involved in writing, illustrating and field testing of the books. Nutrition books are used for English classes at the Tarawa Technical Institute, Kiribati. In the Cook Islands, home economics teachers are using some of the books in their classrooms. The South Pacific Commission Regional Community Education Training Center revised their food, nutrition, and community development curriculum using the nutrition books as a basic text. In Vanuatu, the books were the basis for a reference book for nonformal education centers, and the Red Cross in Fiji has reproduced materials from the books on cancer and other diseases for health and first aid community education. Major funding came from the Canadian International Development Agency, and technical and administrative assistance was obtained from the University of the South Pacific, South Pacific Commission (SPC), Simon Fraser University, and UNICEF. Local governments allowed their staff to assist with writing, field testing, and distribution of materials. Some participants assisted in producing the materials in local languages. An outcome from the project was the formation of a Pacific Island Nutritionist and Dietitians Association. The University of the South Pacific appointed a Nutrition Coordinator to continue the networking among the participants who will also develop a course with the materials for certificate level training in the Pacific Island countries.

  16. Changes in the position of the Subtropical Front south of New Zealand since the last glacial period

    Science.gov (United States)

    Bostock, Helen C.; Hayward, Bruce W.; Neil, Helen L.; Sabaa, Ashwaq T.; Scott, George H.

    2015-07-01

    This study fills an important gap in our understanding of past changes in the Southern Subtropical Front (S-STF) in the southwest Pacific Ocean. Paleo-sea surface temperatures (SST) were estimated from planktic foraminiferal census counts from cores straddling the modern S-STF in the Solander Trough, south of New Zealand. The estimated SST were compared for 6 time slices; glacial period (25-21 ka), Last Glacial Maximum (LGM; 21-18 ka), early deglaciation (18-16 ka), late deglacial/early Holocene period (14-8 ka), mid-Holocene period (8-4 ka), and late Holocene period (4-0 ka). The position of the S-STF was determined by two methods: (1) the location of the 10°C isotherm and (2) the location of the highest SST gradients. These new results suggest that the S-STF was not continuous between east and west of New Zealand during the glacial period. Steep SST gradients indicate that a strong S-STF rapidly shifted south during the LGM and early deglaciation. During the late deglacial and Holocene periods the position of the S-STF differs between the two methods with reduced SST gradients, suggesting a more diffuse S-STF in the Solander Trough at this time. The glacial SST data suggest that the S-STF shifted north to the west of New Zealand, while to the east there was a stronger SST gradient across the front. This was possibly the result of an increased wind stress curl, which could have been caused by stronger, or more northerly Southern Hemisphere westerly winds (SHWW), or a merging of the SHWW split jet in this region.

  17. Long-Term Seasonal and Interannual Patterns of Marine Mammal Strandings in Subtropical Western South Atlantic.

    Directory of Open Access Journals (Sweden)

    Jonatas H F Prado

    Full Text Available Understanding temporal patterns of marine mammal occurrence is useful for establishing conservation strategies. We used a 38 yr-long dataset spanning 1976 to 2013 to describe temporal patterns and trends in marine mammal strandings along a subtropical stretch of the east coast of South America. This region is influenced by a transitional zone between tropical and temperate waters and is considered an important fishing ground off Brazil. Generalized Additive Models were used to evaluate the temporal stranding patterns of the most frequently stranded species. Forty species were documented in 12,540 stranding events. Franciscana (n = 4,574, South American fur seal, (n = 3,419, South American sea lion (n = 2,049, bottlenose dolphins (n = 293 and subantarctic fur seal (n = 219 were the most frequently stranded marine mammals. The seasonality of strandings of franciscana and bottlenose dolphin coincided with periods of higher fishing effort and strandings of South American and subantarctic fur seals with post-reproductive dispersal. For South American sea lion the seasonality of strandings is associated with both fishing effort and post-reproductive dispersal. Some clear seasonal patterns were associated with occurrence of cold- (e.g. subantarctic fur seal and warm-water (e.g. rough-toothed dolphin species in winter and summer, respectively. Inter-annual increases in stranding rate were observed for franciscana and South American fur seal and these are likely related to increased fishing effort and population growth, respectively. For subantarctic fur seal the stranding rate showed a slight decline while for bottlenose dolphin it remained steady. No significant year to year variation in stranding rate was observed for South American sea lion. The slight decrease in frequency of temperate/polar marine mammals and the increased occurrence of subtropical/tropical species since the late 1990s might be associated with environmental changes linked to

  18. Long-Term Seasonal and Interannual Patterns of Marine Mammal Strandings in Subtropical Western South Atlantic

    Science.gov (United States)

    Prado, Jonatas H. F.; Mattos, Paulo H.; Silva, Kleber G.; Secchi, Eduardo R.

    2016-01-01

    Understanding temporal patterns of marine mammal occurrence is useful for establishing conservation strategies. We used a 38 yr-long dataset spanning 1976 to 2013 to describe temporal patterns and trends in marine mammal strandings along a subtropical stretch of the east coast of South America. This region is influenced by a transitional zone between tropical and temperate waters and is considered an important fishing ground off Brazil. Generalized Additive Models were used to evaluate the temporal stranding patterns of the most frequently stranded species. Forty species were documented in 12,540 stranding events. Franciscana (n = 4,574), South American fur seal, (n = 3,419), South American sea lion (n = 2,049), bottlenose dolphins (n = 293) and subantarctic fur seal (n = 219) were the most frequently stranded marine mammals. The seasonality of strandings of franciscana and bottlenose dolphin coincided with periods of higher fishing effort and strandings of South American and subantarctic fur seals with post-reproductive dispersal. For South American sea lion the seasonality of strandings is associated with both fishing effort and post-reproductive dispersal. Some clear seasonal patterns were associated with occurrence of cold- (e.g. subantarctic fur seal) and warm-water (e.g. rough-toothed dolphin) species in winter and summer, respectively. Inter-annual increases in stranding rate were observed for franciscana and South American fur seal and these are likely related to increased fishing effort and population growth, respectively. For subantarctic fur seal the stranding rate showed a slight decline while for bottlenose dolphin it remained steady. No significant year to year variation in stranding rate was observed for South American sea lion. The slight decrease in frequency of temperate/polar marine mammals and the increased occurrence of subtropical/tropical species since the late 1990s might be associated with environmental changes linked to climate change

  19. Deglacial shift in subsurface watermass source in the subtropcal South Pacific North of New Zealand

    Science.gov (United States)

    Schiraldi, B.; Sikes, E. L.; Elmore, A. C.; Cook, M. S.

    2012-12-01

    Glacial-interglacial changes in global temperature are linked with shifts in atmospheric winds and oceanic fronts. Climatic shifts associated with last glacial conditions include a northward shift of the southern hemisphere westerlies, a southward shift of the inter-tropical convergence zone (ITCZ), and a northward shift of the subtropical front (STF) from their modern day locations. These shifts would compress the transition zone in the subtropical south Pacific affecting the source of surface waters. Here we present a δ18Oseawater and δ13C reconstruction from surface dwelling Globogerina bulloides from Bay of Plenty core 87JPC from North of New Zealand to illustrate changes in subtropical South Pacific surface water mass structure over the past 30 ka. Age control is based on tephra stratigraphy benthic foraminiferal δ18O and 14C dates. Sea level reconstruction and surface temperature (SST) reconstructions based on Mg/Ca were used to remove the temperature effect and the ice volume effect was removed from δ18O yielding an estimate of δ18Oseawater of surface-mixed layer water in the Bay of Plenty for the deglaciation. Early in the last glacial period (27-24 ka), reconstructed δ18Oseawater averaged -0.2‰ increasing at 24-21 ka to reach 0.5‰ for 1.2 kyr at the height of the LGM (21-19ka). At 19ka there is a rapid depletion of δ18Oseawater to -0.2‰ after which values average 0.2‰ into the Holocene. More depleted δ18Oseawater values during the LGM suggest surface waters were sourced at high latitudes and were fresher relative to modern. The enrichment through the height of the LGM suggests gradual shift in source waters to more saline and/or lower latitudes. Glacial δ13C holds steady at ~-0.5‰ with a late glacial enrichment maximum of -0.3‰ at 21-20 ka. A subsequent depletion of 0.6‰ at 19.8 ka marks a step change after which δ13C is level through the deglaciation at an average value of -0.8‰ and through the Holocene at -1.0‰. The δ13C

  20. Local Government in the South Pacific Islands

    Directory of Open Access Journals (Sweden)

    Graham Hassall

    2008-04-01

    Full Text Available In this paper we seek to answer some basic questions about the condition of local government in the Pacific. Firstly, we examine what is meant by ‘local government’ in the various islands and for that matter how Pacific Island states have perceived and accepted local government institutions in practice; second, we ask basic questions about existing legal and constitutional recognition and powers; and third, we provide initial findings on current per capita expenditure and local government financial viability in a number of Pacific cities and towns. We also make some observations on current moves towards local government reform.

  1. Variability in the subtropical-tropical cells and its effect on near-surface temperature of the equatorial Pacific: a model study

    Directory of Open Access Journals (Sweden)

    J. F. Lübbecke

    2008-02-01

    Full Text Available A set of experiments utilizing different implementations of the global ORCA-LIM model with horizontal resolutions of 2°, 0.5° and 0.25° is used to investigate tropical and extra-tropical influences on equatorial Pacific SST variability at interannual to decadal time scales. The model experiments use a bulk forcing methodology building on the global forcing data set for 1958 to 2000 developed by Large and Yeager (2004 that is based on a blend of atmospheric reanalysis data and satellite products. Whereas representation of the mean structure and transports of the (sub- tropical Pacific current fields is much improved with the enhanced horizontal resolution, there is only little difference in the simulation of the interannual variability in the equatorial regime between the 0.5° and 0.25° model versions, with both solutions capturing the observed SST variability in the Niño3-region. The question of remotely forced oceanic contributions to the equatorial variability, in particular, the role of low-frequency changes in the transports of the Subtropical Cells (STCs, is addressed by a sequence of perturbation experiments using different combinations of fluxes. The solutions show the near-surface temperature variability to be governed by wind-driven changes in the Equatorial Undercurrent. The relative contributions of equatorial and off-equatorial atmospheric forcing differ between interannual and longer, (multi- decadal timescales: for the latter there is a significant impact of changes in the equatorward transport of subtropical thermocline water associated with the lower branches of the STCs, related to variations in the off-equatorial trade winds. A conspicuous feature of the STC variability is that the equatorward transports in the interior and along the western boundary partially compensate each other at both decadal and interannual time scales, with the strongest transport extrema occurring during El Niño episodes. The behaviour is

  2. Feeding grounds of the eastern South Pacific humpback whale population include the South Orkney Islands

    Directory of Open Access Journals (Sweden)

    Luciano Dalla Rosa

    2012-03-01

    Full Text Available This paper reports on two photo-identified humpback whales (Megaptera novaeangliae that were sighted in different years in the proximity of the South Orkney Islands, at the boundary between the Scotia and Weddell seas (60°54.5'S—46°40.4'W and 60°42.6'S—45°33'W. One of the whales had been previously sighted off Ecuador, a breeding ground for the eastern South Pacific population. The other whale was subsequently resighted in Bransfield Strait, off the western Antarctic Peninsula, a well-documented feeding ground for the same population. These matches give support to a hypothesis that the area south of the South Orkney Islands is occupied by whales from the eastern South Pacific breeding stock. Consequently, we propose 40°W as a new longitudinal boundary between the feeding grounds associated with the eastern South Pacific and western South Atlantic breeding stocks.

  3. Coleopterans associated with plants that form phytotelmata in subtropical and temperate Argentina, South America.

    Science.gov (United States)

    Campos, Raúl E; Fernández, Liliana A

    2011-01-01

    A list of the most common plants that form phytotelmata and their associated coleopterans (aquatic, semi-aquatic and terrestrial) from the northeastern subtropical and temperate area of Argentina, South America with biological and behavioral observations is presented in this study. Species of Poaceae (n = 3), Bromeliaceae (5), Apiaceae (6), Araceae (2), Urticaceae (1), Marantaceae (1), Arecaceae (1), Dipsacaceae (1) and Cyperaceae (1) were identified as phytotelmata. Aquatic species of Scirtidae (2), Dytiscidae (2), and Hydrophilidae (4), semi-aquatic Chelonariidae (2), and terrestrial species of Carabidae (3), Staphylinidae (5), Histeridae (1), Elateridae (1), Cantharidae (1), Cleridae (1), Tenebrionidae (1), Meloidae (1), Anthicidae (1), Chrysomelidae (3), Curculionidae (7) and Apionidae (1) were identified from six species of Eryngium L. (Apiales: Apiaceae), two species of Guadua Kunth (Poales: Poaceae), Aechmea distichantha Lemaire (Poales: Bromeliaceae), and from fallen leaves of Euterpe edulis Martius (Arecales: Arecaceae) from the temperate and subtropical area. The highest species richness was recorded in Eryngium phytotelmata. Fifteen species of beetles inhabit Eryngium cabrerae Pontiroli, 11 in E. horridum Malme, 7 in E. stenophyllum Urban, 4 in E. aff. serra Chamisso and Schlechtendal., 3 in E. elegans Chamisso and Schlechtendal, 2 in E. eburneum Decne and E. pandanifolium Chamisso and Schlechtendal. From bamboo, 6 species of coleopterans were collected from Guadua trinii (Nees) Nees ex Ruprecht and 4 from G. chacoensis (Rojas) Londoño and Peterson. Three species of aquatic coleopterans were recorded from A. distichantha and only one from E. edulis.

  4. Marine boundary layer over the subtropical southeast Pacific during VOCALS-REx – Part 2: Synoptic variability

    Directory of Open Access Journals (Sweden)

    D. A. Rahn

    2010-05-01

    Full Text Available In the second part of this work we study the day-to-day variability of the marine atmospheric boundary layer (MBL over the subtropical southeast Pacific using primarily results from a numerical simulation that covered the whole VOCALS-REx period (October–November 2008. In situ and satellite-derived observations of the MBL height in the offshore region indicate rapid, significant variations (from 500 m to 1700 m a.s.l. over a few days during October. These MBL changes are connected with the passage of midlatitude troughs that altered the large-scale environment over the VOCALS-REx region. In contrast, the synoptic forcing and MBL changes were less prominent during November. Modelled and observed MBL depth at Point Omega (20° S, 85° W compare quite well during October (but the simulation is on average 200 m lower while in November the simulation does not perform as well.

    In the prognostic local MBL height equation the height change, the horizontal MBL height advection, and the large scale vertical velocity at MBL top are calculated explicitly from the simulation. The entrainment velocity is calculated as the residual of the other terms in the equation. While the vertical velocity and residual terms are opposing and generally have the largest magnitude on average, it is the variability in the advection that explains most of the large changes in the MBL depth. Examination of several cases during VOCALS-REx suggests that the advective term is in turn largely controlled by changes in wind direction, driven by midlatitude activity, acting on a MBL that generally slopes down toward the coast. In one phase, the subtropical anticyclone is reinforced and extends toward the Chilean coast, leading to easterly wind that advects low MBL heights from the coast as far as Point Omega. The opposite phase occurs after the passage of an extratropical cyclone over southern Chile, leading to southwesterly wind that advects a deeper MBL towards subtropical

  5. Hydrography and Jack Mackerel stock in the South Pacific

    NARCIS (Netherlands)

    Hintzen, N.T.; Corten, A.A.H.M.; Gerlotto, F.; Brunel, T.P.A.

    2013-01-01

    The study on Hydrography and Jack Mackerel stock (Trachurus murphyi) in the South Pacific is currently one year underway. The main achievement consisted of collecting detailed datasets on Chilean, Peruvian and European fisheries activities and information on the hydrographical / biochemical and

  6. Community structures of actively growing bacteria shift along a north-south transect in the western North Pacific.

    Science.gov (United States)

    Taniguchi, Akito; Hamasaki, Koji

    2008-04-01

    Bacterial community structures and their activities in the ocean are tightly coupled with organic matter fluxes and thus control ocean biogeochemical cycles. Bromodeoxyuridine (BrdU), halogenated nucleoside and thymidine analogue, has been recently used to monitor actively growing bacteria (AGB) in natural environments. We labelled DNA of proliferating cells in seawater bacterial assemblages with BrdU and determined community structures of the bacteria that were possible key species in mediating biochemical reactions in the ocean. Surface seawater samples were collected along a north-south transect in the North Pacific in October 2003 and subjected to BrdU magnetic beads immunocapture and PCR-DGGE (BUMP-DGGE) analysis. Change of BrdU-incorporated community structures reflected the change of water masses along a north-south transect from subarctic to subtropical gyres in the North Pacific. We identified 25 bands referred to AGB as BrdU-incorporated phylotypes, belonging to Alphaproteobacteria (5 bands), Betaproteobacteria (1 band), Gammaproteobacteria (4 bands), Cytophaga-Flavobacterium-Bacteroides (CFB) group bacteria (5 bands), Gram-positive bacteria (6 bands), and Cyanobacteria (4 bands). BrdU-incorporated phylotypes belonging to Vibrionales, Alteromonadales and Gram-positive bacteria appeared only at sampling stations in a subtropical gyre, while those belonging to Roseobacter-related bacteria and CFB group bacteria appeared at the stations in both subarctic and subtropical gyres. Our result revealed phylogenetic affiliation of AGB and their dynamic change along with north-south environmental gradients in open oceans. Different species of AGB utilize different amount and kinds of substrates, which can affect the change of organic matter fluxes along transect.

  7. The Soviet Union in the South Pacific

    Science.gov (United States)

    1988-04-01

    Nuclear-Free Pacific movement."’ A brief look at Vanuatu’s independence movement will reveal the activist and often radical role played by the WCC and...Vanuatu, also supported the Party,𔃾 which led the independence movement , though church support lessened as the Party became more militant. The third...theologist, to work in Vanuatu from 1972 to 1914, a crucial period for the budding independence movement . Provided with a generous travel budget, he

  8. Biogeographic congruence in the south Pacific

    DEFF Research Database (Denmark)

    Seberg, Ole

    1991-01-01

    Zealand, Tasmania and Australia) are congruent. The area cladograms are derived from Nothofagus (Fagacae), Embothriinae (Protaceae), Oreobolus (Cyperaceae), Cyttaria (Helotiales) and Eriococcidae (Homoptera). The resulting general area cladogram showing southern South America as the sister-area to New...

  9. Interaction between Typhoon Vicente (1208) and the western Pacific subtropical high during the Beijing extreme rainfall of 21 July 2012

    Science.gov (United States)

    Wen, Yongren; Xue, Lin; Li, Ying; Wei, Na; Lü, Aimin

    2015-04-01

    The heaviest rainfall in recent six decades fell in Beijing on 21 July 2012, reaching a record of 460 mm within 18 h. This rainfall was a typical remote precipitation event related to Typhoon Vicente (1208). Observational analysis indicates that Vicente influenced distant heavy rainfall by transporting water vapor northward to the Beijing area. This moisture transport was mainly driven by the interaction between Vicente and the western Pacific subtropical high (WPSH) associated with the formation of a low-level southeasterly moisture channel. A set of numerical sensitivity experiments were performed with prescribed typhoons of different intensities to investigate the interaction between Vicente and the WPSH and its effects on this rainstorm process. The results indicate that the WPSH interacting with typhoons of different intensities may exert varying degrees of influence on the development of a southeasterly moisture channel, resulting in a change in rain rate and location over the Beijing area. Specifically, in the presence of an enhanced typhoon, the WPSH shows remarkable withdrawal to the east, which is favorable for a northward extension of the southeasterly moisture channel, thereby increasing moisture supply for the rainstorm. The WPSH tends to stretch westward in a zonal pattern if the typhoon is weakened or removed, hindering the northward extension of the moisture channel. Thus, the rainfall area may be expected to expand or contract, with corresponding increases or decreases in rain rate over the Beijing area with a strengthened or weakened typhoon, respectively.

  10. Patterns in micronekton diversity across the North Pacific Subtropical Gyre observed from the diet of longnose lancetfish (Alepisaurus ferox)

    Science.gov (United States)

    Portner, Elan J.; Polovina, Jeffrey J.; Choy, C. Anela

    2017-07-01

    We examined the diet of a common midwater predator, the longnose lancetfish (Alepisaurus ferox, n=1371), with respect to fork length, season, and capture location within the North Pacific Subtropical Gyre (NPSG). While A. ferox fed diversely across 97 prey families, approximately 70% of its diet by wet weight consisted of seven prey families (fishes: Sternoptychidae, Anoplogastridae, Omosudidae, Alepisauridae; hyperiid amphipods: Phrosinidae; octopods: Amphitretidae; polychaetes: Alciopidae). Altogether, these micronekton prey families constitute a poorly known forage community distinct from those exploited by other pelagic predators and poorly sampled by conventional methods. We demonstrate ontogenetic variation in diet between two size classes of A. ferox (fish and octopods, fewer crustaceans, and were more cannibalistic than small A. ferox. Ontogenetic shifts in vertical foraging habitat were observed as the consumption of larger and more mesopelagic prey with increasing fork length. Spatial and seasonal variation in the diet of A. ferox is consistent with expected patterns of variation in prey distribution with respect to oceanographic features of the NPSG. Within both size classes, the diets of specimens collected from the oligotrophic core of the NPSG were more diverse than those collected near the boundaries of the gyre and appeared to track seasonal variation in the position of the northern boundary of the gyre. Our data suggest seasonal and spatial variability in the composition of midwater forage communities exploited by A. ferox across the NPSG, and demonstrate that sustained monitoring of diet could provide valuable insights into long-term changes in these understudied communities.

  11. On the Nature of Severe Orographic Thunderstorms near the Andes in Subtropical South America

    Science.gov (United States)

    Rasmussen, Kristen Lani Emi

    Identifying common features and differences between the mechanisms producing extreme convection near major mountain ranges of the world is an essential step toward a general understanding of orographic precipitation on a global scale. The overarching objective of this dissertation is to understand and examine orographic convective processes in general, while specifically focusing on systems in the lee of the Andes Mountains. Diagnosing the key ingredients necessary for generating high impact weather near extreme topography is crucial to our understanding of orographic precipitating systems. An investigation of the most intense storms in 11 years of TRMM Precipitation Radar (PR) data has shown a tendency for squall lines to initiate and develop east of the Andes with a mesoscale organization similar to storms in the U.S. Great Plains (Rasmussen and Houze 2011). In subtropical South America, however, the topographical influence on the convective initiation and maintenance of the mesoscale convective systems (MCSs) is unique. The Andes and other mountainous terrain of Argentina focus deep convective initiation in the foothills of western Argentina (Romatschke and Houze 2010; Rasmussen and Houze 2011). Subsequent to initiation, the convection often evolves into propagating MCSs similar to those seen over the U.S. Great Plains sometimes producing damaging tornadoes, hail and floods across a wide agricultural region (Rasmussen and Houze 2011; Rasmussen et al. 2014b). The TRMM satellite was designed to determine the spatial and temporal variation of tropical and subtropical rainfall amounts and storm structures around the globe with the goal of understanding the factors controlling the precipitation. However, the TRMM PR algorithm significantly underestimates surface rainfall in deep convection over land (Nesbitt et al. 2004; Iguchi et al. 2009; Kozu et al. 2009). When the algorithm rates are compared to a range of conventional Z-R relations, the rain bias tends to be

  12. A map-based South Pacific rainfall climatology

    Science.gov (United States)

    Lorrey, A.; Diamond, H.; Renwick, J.; Salinger, J.; Gergis, J.; Dalu, G.

    2008-12-01

    The lives of more than four million people that reside in the South Pacific are greatly affected by rainfall variability. This region is subjected to large rainfall anomalies on seasonal timescales due to tropical cyclone occurrences, ENSO activity, and the AAO. Regional climate anomalies are also dictated by the IPO on multi- decadal scales that alter the motions of large-scale circulation features like the South Pacific Convergence Zone (SPCZ). Strong climate change impacts are anticipated for this region, so gauging the severity of rainfall variations that can occur are paramount for implementing appropriate climate change adaptation measures. Lack of historical rainfall records and documentation of other climate data hinders our current understanding of South Pacific climate variability. Climate data rescue activities are currently aimed at recovering, archiving, and digitising this information to rectify this issue. This research aims to examine the rainfall database administered by the Island Climate Update (ICU) project, which is contributed to by all Pacific Island national meteorological services (NMS), Meteo-France (New Caledonia and French Polynesia), NIWA (New Zealand), NOAA (USA), the IRI (USA), and the Bureau of Meteorology (Australia). Monthly rainfall totals for all stations in the ICU database were assessed, and allowed construction of master rainfall chronologies for all or portions of the major South Pacific Island nations. Climatic norms were then calculated over common time periods, and monthly-resolved rainfall anomaly maps for the South Pacific covering 1951-2008 were undertaken. Immediate benefits of this exercise have pointed out holes in the rainfall network that can be specifically targeted for data rescue in the near future, which can be achieved by providing financial assistance to Pacific Island NMSs. In addition, there is ample scope to extend the rainfall anomaly map time series into the early 1900s using a spatially degraded data

  13. Millennial-scale plankton regime shifts in the subtropical North Pacific Ocean.

    Science.gov (United States)

    McMahon, Kelton W; McCarthy, Matthew D; Sherwood, Owen A; Larsen, Thomas; Guilderson, Thomas P

    2015-12-18

    Climate change is predicted to alter marine phytoplankton communities and affect productivity, biogeochemistry, and the efficacy of the biological pump. We reconstructed high-resolution records of changing plankton community composition in the North Pacific Ocean over the past millennium. Amino acid-specific δ(13)C records preserved in long-lived deep-sea corals revealed three major plankton regimes corresponding to Northern Hemisphere climate periods. Non-dinitrogen-fixing cyanobacteria dominated during the Medieval Climate Anomaly (950-1250 Common Era) before giving way to a new regime in which eukaryotic microalgae contributed nearly half of all export production during the Little Ice Age (~1400-1850 Common Era). The third regime, unprecedented in the past millennium, began in the industrial era and is characterized by increasing production by dinitrogen-fixing cyanobacteria. This picoplankton community shift may provide a negative feedback to rising atmospheric carbon dioxide concentrations. Copyright © 2015, American Association for the Advancement of Science.

  14. Phytoplankton across Tropical and Subtropical Regions of the Atlantic, Indian and Pacific Oceans.

    Directory of Open Access Journals (Sweden)

    Marta Estrada

    Full Text Available We examine the large-scale distribution patterns of the nano- and microphytoplankton collected from 145 oceanic stations, at 3 m depth, the 20% light level and the depth of the subsurface chlorophyll maximum, during the Malaspina-2010 Expedition (December 2010-July 2011, which covered 15 biogeographical provinces across the Atlantic, Indian and Pacific oceans, between 35°N and 40°S. In general, the water column was stratified, the surface layers were nutrient-poor and the nano- and microplankton (hereafter phytoplankton, for simplicity, although it included also heterotrophic protists community was dominated by dinoflagellates, other flagellates and coccolithophores, while the contribution of diatoms was only important in zones with shallow nutriclines such as the equatorial upwelling regions. We applied a principal component analysis to the correlation matrix among the abundances (after logarithmic transform of the 76 most frequent taxa to synthesize the information contained in the phytoplankton data set. The main trends of variability identified consisted of: 1 A contrast between the community composition of the upper and the lower parts of the euphotic zone, expressed respectively by positive or negative scores of the first principal component, which was positively correlated with taxa such as the dinoflagellates Oxytoxum minutum and Scrippsiella spp., and the coccolithophores Discosphaera tubifera and Syracosphaera pulchra (HOL and HET, and negatively correlated with taxa like Ophiaster hydroideus (coccolithophore and several diatoms, 2 a general abundance gradient between phytoplankton-rich regions with high abundances of dinoflagellate, coccolithophore and ciliate taxa, and phytoplankton-poor regions (second principal component, 3 differences in dominant phytoplankton and ciliate taxa among the Atlantic, the Indian and the Pacific oceans (third principal component and 4 the occurrence of a diatom-dominated assemblage (the fourth

  15. Phytoplankton across Tropical and Subtropical Regions of the Atlantic, Indian and Pacific Oceans.

    Science.gov (United States)

    Estrada, Marta; Delgado, Maximino; Blasco, Dolors; Latasa, Mikel; Cabello, Ana María; Benítez-Barrios, Verónica; Fraile-Nuez, Eugenio; Mozetič, Patricija; Vidal, Montserrat

    2016-01-01

    We examine the large-scale distribution patterns of the nano- and microphytoplankton collected from 145 oceanic stations, at 3 m depth, the 20% light level and the depth of the subsurface chlorophyll maximum, during the Malaspina-2010 Expedition (December 2010-July 2011), which covered 15 biogeographical provinces across the Atlantic, Indian and Pacific oceans, between 35°N and 40°S. In general, the water column was stratified, the surface layers were nutrient-poor and the nano- and microplankton (hereafter phytoplankton, for simplicity, although it included also heterotrophic protists) community was dominated by dinoflagellates, other flagellates and coccolithophores, while the contribution of diatoms was only important in zones with shallow nutriclines such as the equatorial upwelling regions. We applied a principal component analysis to the correlation matrix among the abundances (after logarithmic transform) of the 76 most frequent taxa to synthesize the information contained in the phytoplankton data set. The main trends of variability identified consisted of: 1) A contrast between the community composition of the upper and the lower parts of the euphotic zone, expressed respectively by positive or negative scores of the first principal component, which was positively correlated with taxa such as the dinoflagellates Oxytoxum minutum and Scrippsiella spp., and the coccolithophores Discosphaera tubifera and Syracosphaera pulchra (HOL and HET), and negatively correlated with taxa like Ophiaster hydroideus (coccolithophore) and several diatoms, 2) a general abundance gradient between phytoplankton-rich regions with high abundances of dinoflagellate, coccolithophore and ciliate taxa, and phytoplankton-poor regions (second principal component), 3) differences in dominant phytoplankton and ciliate taxa among the Atlantic, the Indian and the Pacific oceans (third principal component) and 4) the occurrence of a diatom-dominated assemblage (the fourth principal

  16. Phytoplankton across Tropical and Subtropical Regions of the Atlantic, Indian and Pacific Oceans

    Science.gov (United States)

    Estrada, Marta; Delgado, Maximino; Blasco, Dolors; Latasa, Mikel; Cabello, Ana María; Benítez-Barrios, Verónica; Fraile-Nuez, Eugenio; Mozetič, Patricija; Vidal, Montserrat

    2016-01-01

    We examine the large-scale distribution patterns of the nano- and microphytoplankton collected from 145 oceanic stations, at 3 m depth, the 20% light level and the depth of the subsurface chlorophyll maximum, during the Malaspina-2010 Expedition (December 2010-July 2011), which covered 15 biogeographical provinces across the Atlantic, Indian and Pacific oceans, between 35°N and 40°S. In general, the water column was stratified, the surface layers were nutrient-poor and the nano- and microplankton (hereafter phytoplankton, for simplicity, although it included also heterotrophic protists) community was dominated by dinoflagellates, other flagellates and coccolithophores, while the contribution of diatoms was only important in zones with shallow nutriclines such as the equatorial upwelling regions. We applied a principal component analysis to the correlation matrix among the abundances (after logarithmic transform) of the 76 most frequent taxa to synthesize the information contained in the phytoplankton data set. The main trends of variability identified consisted of: 1) A contrast between the community composition of the upper and the lower parts of the euphotic zone, expressed respectively by positive or negative scores of the first principal component, which was positively correlated with taxa such as the dinoflagellates Oxytoxum minutum and Scrippsiella spp., and the coccolithophores Discosphaera tubifera and Syracosphaera pulchra (HOL and HET), and negatively correlated with taxa like Ophiaster hydroideus (coccolithophore) and several diatoms, 2) a general abundance gradient between phytoplankton-rich regions with high abundances of dinoflagellate, coccolithophore and ciliate taxa, and phytoplankton-poor regions (second principal component), 3) differences in dominant phytoplankton and ciliate taxa among the Atlantic, the Indian and the Pacific oceans (third principal component) and 4) the occurrence of a diatom-dominated assemblage (the fourth principal

  17. Gross and microscopic pathology of lesions in Pocillopora spp. from the subtropical eastern Pacific

    Science.gov (United States)

    Rodríguez-Villalobos, Jenny Carolina; Rocha-Olivares, Axayácatl; Work, Thierry M.; Calderon-Aguilera, Luis Eduardo; Cáceres-Martínez, Jorge Abelardo

    2014-01-01

    Coral reefs are threatened by a variety of factors including diseases that have caused significant damage in some regions such as in the Caribbean. At present, no data are available on coral diseases in the Mexican Pacific where Pocillopora spp. is a dominant component of coral communities. Here, we describe gross and microscopic morphology of lesions found in pocilloporids at four sites in the Mexican Pacific. Corals were identified and their lesions photographed and quantified in the field. Tissue samples were collected from healthy and affected colonies for histopathology. We recorded seven species of pocilloporids at the study sites with Isla Isabel being the location with the highest coral diversity (H′ = 1.27). Lesions were present in 42% of the colonies and included discoloration (32%), predation-induced tissue loss (30%), unexplained tissue loss (3%) and overgrowth by sponges or algae (35%). The most affected species, P. damicornis (50%), was also one of the most common in the region. No species was more prone to a particular lesion, but there was a significant association between location and the presence of lesions. Northern Islas Marietas (61%) and Isla Isabel (41%) had the highest prevalence of lesions, followed by Manzanillo (37%) and Bahías de Huatulco (23%). Histological changes included atrophy of the surface body wall with depletion of zooxanthellae (91%) in corals with discoloration (bleaching). Ablation of tissue from mesoglea (18%) was also observed. Colonies with unexplained tissue loss showed atrophy and thinning of the epidermis (89%), characterized by cuboidal instead of pseudocolumnar cells normally found in healthy pseudocolumnar ciliated epithelium. Bacterial aggregates between the mesoglea and gastrodermis (11%) were very conspicuous in healthy and diseased corals. Lesions produced by fish bites and gastropods were associated with tissue atrophy (40%) and, in some cases, algal overgrowth near the lesion (20%). No infectious

  18. The Mexican Coastal Current: A subsurface seasonal bridge that connects the tropical and subtropical Northeastern Pacific

    Science.gov (United States)

    Gómez-Valdivia, F.; Parés-Sierra, A.; Flores-Morales, A. L.

    2015-11-01

    We used a three-dimensional numerical model to analyze the seasonal variability of the coastal circulation off SW Mexico. In agreement with previous research, our model reproduced a Mexican Coastal Current (MCC) that dominates the regional poleward circulation. The modeled dynamics evidenced an energetic semiannual component that governed the subsurface seasonal variability of this poleward flow. Below the thermocline the MCC was stronger during spring and fall, when it reached subsurface seasonal-averaged velocities of ∼10 cms-1 and flowed continuously from the Gulf of Tehuantepec to the entrance of the Gulf of California. There, the subsurface MCC bifurcated in one branch that continued along the coast of mainland Mexico and a second branch that crossed the gulf and joined the California Undercurrent. Instead of the local wind, the semiannual MCC variability was induced by the transit of equatorial Kelvin waves whose upwelling (downwelling) phase propagation strengthen (weakened) the subsurface poleward circulation along the Tropical Pacific off Mexico. The MCC dynamics reported in this study accounts for the, previously reported, semiannual variability of the alongshore transport and salinity content in the southern Gulf of California. Moreover, the subsurface bridge between the MCC and the California Current System represents an external source of momentum that helps to explain the intensification of the California Undercurrent during spring and fall.

  19. Investigating the Trophic Ecology of the Fish Genus Cyclothone in the North Pacific Subtropical Gyre Using Stable Isotope Techniques

    Science.gov (United States)

    Gloeckler, K.; Ko, W.; Choy, C. A.; Hannides, C. C.; Close, H. G.; Popp, B. N.; Drazen, J.

    2016-02-01

    The meso- and bathypelagic fish genus Cyclothone, commonly known as bristlemouths, are the most abundant vertebrates on the planet. Despite their abundance, little is known about their trophic ecology. A few studies have used traditional stomach content analysis and found that the majority of individuals had empty stomachs and a few contained copepod and ostracod remains. We used bulk tissue carbon and nitrogen isotopes, and compound-specific nitrogen isotope analysis of amino acids (AA-CSIA) to investigate the trophic ecology of this genus from individuals collected at Station ALOHA, in the North Pacific Subtropical Gyre. Two cosmopolitan species were abundant, the shallower living Cyclothone alba (425-625 m) and the deeper living Cyclothone pallida (600 - 1300 m), and appear to have different feeding ecologies. While the bulk 13C and 15N contents of C. alba were similar to those of other zooplanktivorous micronekton, the bulk 13C and 15N contents of C. pallida were much higher than those of zooplanktivorous micronekton and suggest either (1) that they feed at a similar trophic level to large predatory fishes such as Thunnus albacares and Coryphaena hipurrus or (2) that the baseline isotopic values of their food web are substantially different. AA-CSIA showed that the trophic position (TP) of C. pallida was 2.3 - 3.2 (±0.28), that is, much lower than the TP of large predatory fishes. Additionally, the δ15N values of the `source' amino acid phenylalanine (d15NPHE) were very high, indicating baseline isotopic values within the range of bacterially-altered suspended particles. Suspended particles have often been overlooked as a significant source of carbon in the deep sea despite discrepancies between the supply of carbon via sinking particles and estimated demand of carbon by deep sea organisms. These results suggest that a suspended particle based food web is important to at least some deep-sea fauna.

  20. Annual Net Community Production in the Western Subtropical North Pacific Determined from Argo-O2 Measurements

    Science.gov (United States)

    Yang, B.; Emerson, S. R.; Bushinsky, S. M.

    2016-02-01

    Export of organic carbon from the surface ocean to depth (the biological pump) helps maintain the pCO2 of the atmosphere and the O2 content of the oxygen minimum zones of the ocean. In the upper ocean, at steady state over a seasonal cycle the net organic carbon export is equal to the Annual Net Community Production (ANCP). The geographic distribution of this quantity determined by satellite-predicted Net Primary Production (NPP) and the recycling efficiency in the euphotic zone is more heterogeneous than the limited experimental estimates of ANCP. We evaluate the relationship between these two estimates of ANCP in the subtropical Western North Pacific Ocean ( 165o E and 20o N) using oxygen measurements on Argo Floats. In January of 2015 we deployed four floats with Anderaa oxygen sensors attached to a 60 cm stick on top of the float end cap, which can be readily calibrated against atmospheric pO2. We present data from these floats and air-sea oxygen flux calculations. The degree of oxygen supersaturation in summer is 1-2 percent, and in winter it fluctuates between being over and undersaturated. Evaluating the role of bubbles in winter is critical to an accurate determination of the annual flux. While there is not a full year of data at the time of writing this abstract, there will be when the Ocean Science meeting is held. So far, after nine months of measurements, there is a net flux of oxygen to the atmosphere, indicating that photosynthesis exceeds respiration. In February we will present a full annual cycle of air-sea oxygen flux and an estimate of ANCP in this very rarely studied region of the ocean.

  1. Vertical gradients in species richness and community composition across the twilight zone in the North Pacific Subtropical Gyre.

    Science.gov (United States)

    Sommer, Stephanie A; Van Woudenberg, Lauren; Lenz, Petra H; Cepeda, Georgina; Goetze, Erica

    2017-11-01

    Although metazoan animals in the mesopelagic zone play critical roles in deep pelagic food webs and in the attenuation of carbon in midwaters, the diversity of these assemblages is not fully known. A metabarcoding survey of mesozooplankton diversity across the epipelagic, mesopelagic and upper bathypelagic zones (0-1500 m) in the North Pacific Subtropical Gyre revealed far higher estimates of species richness than expected given prior morphology-based studies in the region (4,024 OTUs, 10-fold increase), despite conservative bioinformatic processing. Operational taxonomic unit (OTU) richness of the full assemblage peaked at lower epipelagic-upper mesopelagic depths (100-300 m), with slight shoaling of maximal richness at night due to diel vertical migration, in contrast to expectations of a deep mesopelagic diversity maximum as reported for several plankton groups in early systematic and zoogeographic studies. Four distinct depth-stratified species assemblages were identified, with faunal transitions occurring at 100 m, 300 m and 500 m. Highest diversity occurred in the smallest zooplankton size fractions (0.2-0.5 mm), which had significantly lower % OTUs classified due to poor representation in reference databases, suggesting a deep reservoir of poorly understood diversity in the smallest metazoan animals. A diverse meroplankton assemblage also was detected (350 OTUs), including larvae of both shallow and deep living benthic species. Our results provide some of the first insights into the hidden diversity present in zooplankton assemblages in midwaters, and a molecular reappraisal of vertical gradients in species richness, depth distributions and community composition for the full zooplankton assemblage across the epipelagic, mesopelagic and upper bathypelagic zones. © 2017 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

  2. Feeding ecology of mesopelagic zooplankton of the subtropical and subarctic North Pacific Ocean determined with fatty acid biomarkers

    Science.gov (United States)

    Wilson, S. E.; Steinberg, D. K.; Chu, F.-L. E.; Bishop, J. K. B.

    2010-10-01

    Mesopelagic zooplankton may meet their nutritional and metabolic requirements in a number of ways including consumption of sinking particles, carnivory, and vertical migration. How these feeding modes change with depth or location, however, is poorly known. We analyzed fatty acid (FA) profiles to characterize zooplankton diet and large particle (>51 μm) composition in the mesopelagic zone (base of euphotic zone -1000 m) at two contrasting time-series sites in the subarctic (station K2) and subtropical (station ALOHA) Pacific Ocean. Total FA concentration was 15.5 times higher in zooplankton tissue at K2, largely due to FA storage by seasonal vertical migrators such as Neocalanus and Eucalanus. FA biomarkers specific to herbivory implied a higher plant-derived food source at mesotrophic K2 than at oligotrophic ALOHA. Zooplankton FA biomarkers specific to dinoflagellates and diatoms indicated that diatoms, and to a lesser extent, dinoflagellates were important food sources at K2. At ALOHA, dinoflagellate FAs were more prominent. Bacteria-specific FA biomarkers in zooplankton tissue were used as an indicator of particle feeding, and peaks were recorded at depths where known particle feeders were present at ALOHA (e.g., ostracods at 100-300 m). In contrast, depth profiles of bacterial FA were relatively constant with depth at K2. Diatom, dinoflagellate, and bacterial biomarkers were found in similar proportions in both zooplankton and particles with depth at both locations, providing additional evidence that mesopelagic zooplankton consume sinking particles. Carnivory indices were higher and increased significantly with depth at ALOHA, and exhibited distinct peaks at K2, representing an increase in dependence on other zooplankton for food in deep waters. Our results indicate that feeding ecology changes with depth as well as by location. These changes in zooplankton feeding ecology from the surface through the mesopelagic zone, and between contrasting environments

  3. A comparison of mesopelagic mesozooplankton community structure in the subtropical and subarctic North Pacific Ocean

    Science.gov (United States)

    Steinberg, Deborah K.; Cope, Joseph S.; Wilson, Stephanie E.; Kobari, T.

    2008-07-01

    Mesopelagic mesozooplankton communities of an oligotrophic (Hawaii Ocean Time series-HOT station ALOHA) and a mesotrophic (Japanese time-series station K2) environment in the North Pacific Ocean are compared as part of a research program investigating the factors that control the efficiency of particle export to the deep sea (VERtical Transport In the Global Ocean—VERTIGO). We analyzed zooplankton (>350 μm) collected from net tows taken between 0 and 1000 m at each site to investigate the biomass size structure and the abundance of the major taxonomic groups in discrete depth intervals throughout the water column. Biomass of zooplankton at K2 over all depths was approximately an order of a magnitude higher than at ALOHA, with a significantly higher proportion of the biomass at K2 in the larger (>2 mm) size classes. This difference was mostly due to the abundance at K2 of the large calanoid copepods Neocalanus spp. and Eucalanus bungii, which undergo ontogenetic (seasonal) vertical migration. The overall strength of diel vertical migration was higher at K2, with a mean night:day biomass ratio in the upper 150 m of 2.5, vs. a ratio of 1.7 at ALOHA. However, the amplitude of the diel migration (change in weighted mean depth between day and night) was higher at ALOHA for all biomass size classes, perhaps due to deeper light penetration causing deeper migration to avoid visual predators. A number of taxa known to feed on suspended or sinking detritus showed distinct peaks in the mesopelagic zone, which affects particle transport efficiency at both sites. These taxa include calanoid and poecilostomatoid (e.g., Oncaea spp.) copepods, salps, polychaetes, and phaeodarian radiolaria at K2, harpacticoid copepods at ALOHA, and ostracods at both sites. We found distinct layers of carnivores (mainly gelatinous zooplankton) in the mesopelagic at K2 including chaetognaths, hydrozoan medusae, polychaetes, and gymnosome pteropods, and, in the upper mesopelagic zone, of

  4. Synoptic and dynamical analysis of subtropical cyclone Anita (2010) and its potential for tropical transition over the South Atlantic Ocean

    Science.gov (United States)

    Dias Pinto, João. Rafael; Reboita, Michelle Simões; da Rocha, Rosmeri Porfírio

    2013-10-01

    cyclogenesis and tropical transitions (TT) over the South Atlantic Ocean only received attention after the first documented Hurricane Catarina occurred close to the southern Brazilian coast in March 2004. However, due to the lack of studies in this part of the Atlantic Ocean, it is still unclear what the main environmental conditions and dynamical processes associated with TT or even subtropical cyclogenesis are over the region. This study presents a synoptic and dynamical analysis of the subtropical cyclone Anita which occurred in March 2010 near the Brazilian coast. This system started as a pure subtropical cyclone, evolved to a condition favorable to TT, later developed into a cold-core structure, and decayed as an extratropical cyclone. During the period favorable for TT, the turbulent heat fluxes (latent plus sensible) from the ocean decreased, and Anita started interacting with another extratropical disturbance, preventing the TT to happen. This interaction, in turn, increased the vertical wind shear, allowed the extratropical transition to occur, and promoted the westward displacement of Anita to colder waters, thus decreasing the turbulent heat fluxes. The results suggest that the combination of a dipole blocking pattern aloft, with contribution from barotropic energy conversions, and strong turbulent fluxes is an important ingredient for tropical storm development. Hybrid storms in such environmental conditions can be one form of precursors of hurricanes over the South Atlantic.

  5. Limited-are a modelling of stratocumulus over South-Eastern Pacific

    Directory of Open Access Journals (Sweden)

    M. Andrejczuk

    2012-04-01

    Full Text Available This paper presents application of the Weather Research and Forecasting (WRF model to limited-area modeling of atmospheric processes over the subtropical south-eastern Pacific, with the emphasis on the stratocumulus-topped boundary layer. The simulations cover a domain from the VAMOS (Variability of the American Monsoon Systems Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx field project conducted in the subtropical south-eastern Pacific in October and November 2008. We focus on a day where the UK's BAe-146 research aircraft encountered Pockets of Open Cells (POCs at the very western edge of its flight track, rather than on the entire campaign as investigated in previous limited-area modeling studies. Model results are compared to aircraft observations with the main conclusion that the simulated stratocumulus-topped boundary layer is significantly too shallow. This appears to be a combination of an already too shallow boundary layer in the dataset used to provide initial and lateral boundary conditions, and the inability of the WRF model to increase the boundary-layer height. Several sensitivity simulations, applying different subgrid-scale parameterizations available in the model, a larger computational domain and longer simulations, as well as a different dataset providing initial and lateral boundary conditions were all tried to improve the simulation. These changes appeared to have a rather small effect on the results. The model does simulate the formation of mesoscale cloud-free regions that one might consider similar to Pockets of Open Cells observed in nature. However, formation of these regions does not seem to be related to drizzle-induced transition from open- to closed-cell circulations as simulated by LES models. Instead, the cloud-free regions appear to result from mesoscale variations of the lower-tropspheric vertical velocity. Areas of negative vertical velocity with minima (a few cm s−1 near the

  6. Desertification of subtropical thicket in the Eastern Cape, South Africa: Are there alternatives?

    Science.gov (United States)

    Kerley, G I; Knight, M H; de Kock, M

    1995-01-01

    The Eastern Cape Subtropical Thicket (ECST) froms the transition between forest, semiarid karroid shrublands, and grassland in the Eastern Cape, South Africa. Undegraded ECST forms an impenetrable, spiny thicket up to 3 m high consisting of a wealth of growth forms, including evergreen plants, succulent and deciduous shrubs, lianas, grasses, and geophytes. The thicket dynamics are not well understood, but elephants may have been important browsers and patch disturbance agents. These semiarid thickets have been subjected to intensive grazing by domestic ungulates, which have largely replaced indigenous herbivores over the last 2 centuries. Overgrazing has extensively degraded vegetation, resulting in the loss of phytomass and plant species and the replacement of perennials by annuals. Coupled with these changes are alterations of soil structure and secondary productivity. This rangeland degradation has largely been attributed to pastoralism with domestic herbivores. The impact of indigenous herbivores differs in scale, intensity, and nature from that of domestic ungulates. Further degradation of the ECST may be limited by alternative management strategies, including the use of wildlife for meat production and ecotourism. Producing meat from wildlife earns less income than from domestic herbivores but is ecologically sustainable. The financial benefits of game use can be improved by developing expertise, technology, and marketing. Ecotourism is not well developed in the Eastern Cape although the Addo Elephant National Park is a financial success and provides considerable employment benefits within an ecologically sustainable system. The density of black rhinoceros and elephant in these thickets is among the highest in Africa, with high population growth and the lowest poaching risk. The financial and ecological viability of ecotourism and the conservation status of these two species warrant expanding ecotourism in the Eastern Cape, thereby reducing the probability of

  7. Gaseous elemental mercury (GEM) fluxes over canopy of two typical subtropical forests in south China

    Science.gov (United States)

    Yu, Qian; Luo, Yao; Wang, Shuxiao; Wang, Zhiqi; Hao, Jiming; Duan, Lei

    2018-01-01

    Mercury (Hg) exchange between forests and the atmosphere plays an important role in global Hg cycling. The present estimate of global emission of Hg from natural source has large uncertainty, partly due to the lack of chronical and valid field data, particularly for terrestrial surfaces in China, the most important contributor to global atmospheric Hg. In this study, the micrometeorological method (MM) was used to continuously observe gaseous elemental mercury (GEM) fluxes over forest canopy at a mildly polluted site (Qianyanzhou, QYZ) and a moderately polluted site (Huitong, HT, near a large Hg mine) in subtropical south China for a full year from January to December in 2014. The GEM flux measurements over forest canopy in QYZ and HT showed net emission with annual average values of 6.67 and 0.30 ng m-2 h-1, respectively. Daily variations of GEM fluxes showed an increasing emission with the increasing air temperature and solar radiation in the daytime to a peak at 13:00, and decreasing emission thereafter, even as a GEM sink or balance at night. High temperature and low air Hg concentration resulted in the high Hg emission in summer. Low temperature in winter and Hg absorption by plant in spring resulted in low Hg emission, or even adsorption in the two seasons. GEM fluxes were positively correlated with air temperature, soil temperature, wind speed, and solar radiation, while it is negatively correlated with air humidity and atmospheric GEM concentration. The lower emission fluxes of GEM at the moderately polluted site (HT) when compared with that in the mildly polluted site (QYZ) may result from a much higher adsorption fluxes at night in spite of a similar or higher emission fluxes during daytime. This shows that the higher atmospheric GEM concentration at HT restricted the forest GEM emission. Great attention should be paid to forests as a crucial increasing Hg emission source with the decreasing atmospheric GEM concentration in polluted areas because of Hg

  8. Differential Effects of Nitrate (NO3-), Ammonium (NH4+) and Urea on Phytoplankton Communities in the North Pacific Subtropical Gyre.

    Science.gov (United States)

    Mills, M. M.; Shilova, I. N.; Robidart, J.; Bjorkman, K. M.; van Dijken, G.; Turk-Kubo, K.; Kolber, Z.; Achterberg, E. P.; Church, M. J.; Arrigo, K. R.; Zehr, J. P.

    2016-02-01

    Nitrogen (N) has long been known to limit phytoplankton growth and productivity in large regions of the oceans. Likewise, the form and supply of N are important controls on microbial community composition, activity and ultimately ecosystem function. However, the effect of different chemical N species on complex natural phytoplankton communities in the open ocean is not well-known. We used bioassays to examine and compare responses of phytoplankton communities to the addition of either NO3-, NH4+ or Urea in the North Pacific Subtropical Gyre during Aug.-Sept. 2014 (NEMO cruise). The effects of iron (Fe) and phosphorus (P) on N assimilation were also examined. Phytoplankton biomass and primary productivity were N-limited in the central and eastern parts of the transect, whereas no response was observed to any of the N substrates (unless added together with P) in the western part of the transect. In response to N substrate additions, the central region of the NPSG had a significant and rapid (within 24 h) shift in heterotrophic and phytoplankton community composition and photosynthetic activity relative to changes in an experiment at the eastern edge of the NPSG. In the experiments where the phytoplankton community was N-limited, urea addition resulted in the highest response in primary productivity and chlorophyll a, largely due to the response by Prochlorococcus. The additions of NO3- and urea stimulated Synechococcus populations in both eastern and central regions, but the response in the eastern part of the NPSG was similar to the Fe addition response. Picoeukaryotic population increased most in response to NH4+ in the central NPSG and in response to all N forms and also to Fe in the eastern part. Uptake rates of the different N species were also variable between different phytoplankton groups (Prochlorococcus, Synechococcus, and picoeukaryotic phytoplankton). These variable responses are indicative of diverse ecotypes and physiological states within and between

  9. Decoupling between bacterial production and primary production over multiple time scales in the North Pacific Subtropical Gyre

    Science.gov (United States)

    Viviani, Donn A.; Church, Matthew J.

    2017-03-01

    We measured rates of 3H-leucine (3H-Leu) incorporation, as a proxy for bacterial production, at Station ALOHA (22°45‧N, 158°W) in the oligotrophic North Pacific Subtropical Gyre (NPSG). We report measurements conducted between January 2011 and April 2013, examining variability in 3H-Leu incorporation over diel, daily, and monthly time scales. Rates of 3H-Leu were evaluated in the context of contemporaneous 14C-based primary productivity (14C-PP) to identify potential temporal coupling between these measures of productivity. Throughout the upper ocean (0-125 m), rates of 3H-Leu incorporation measured in the light (3H-LeuLight) were stimulated (1.5-fold, on average) relative to measurements in the dark (3H-LeuDark). At monthly scales, rates of 3H-LeuLight and 3H-LeuDark varied 4.9-fold and 3.8-fold, respectively, while rates of 14C-PP varied 1.7-fold. Rates of 14C-PP were often elevated during summer months (May through August) when incident light flux was greatest, while rates of both 3H-LeuLight and 3H-LeuDark often peaked in early fall (August through October) when seawater temperatures were maximal. Near-daily measurements of 3H-Leu incorporation and 14C-PP conducted over a 62-day period in the summer of 2012 revealed that rates of 3H-LeuLight and 3H-LeuDark varied 2.5 and 2.0-fold, respectively, similar to 1.8-fold daily variability observed in rates of 14C-PP. Over diel time scales, rates of 3H-LeuLight and 3H-LeuDark demonstrated different patterns, with rates of 3H-LeuLight elevated at mid-day and rates of 3H-LeuDark greatest in the early evening. Together, these results suggest that in this oligotrophic ecosystem, photosynthetic production of organic matter and bacterial production can be temporally uncoupled across daily to seasonal scales.

  10. Heterotrophic prokaryote distribution along a 2300 km transect in the North Pacific subtropical gyre during a strong La Niña conditions: relationship between distribution and hydrological conditions

    Directory of Open Access Journals (Sweden)

    M. Girault

    2015-06-01

    Full Text Available The spatial distribution of heterotrophic prokaryotes was investigated during the Tokyo–Palau cruise in the western part of the North Pacific subtropical gyre (NPSG along a north–south transect between 33.60 and 13.25° N. The cruise was conducted in three different hydrological areas identified as the Kuroshio region, the subtropical gyre area and the transition zone. Two eddies were crossed along the transect: one cold-core cyclonic eddy and one warm-core anticyclonic eddy and distributions of the heterotrophic prokaryotes were recorded. By using analytical flow cytometry and a nucleic acid staining protocol, heterotrophic prokaryotes were discriminated into three subgroups depending on their nucleic acid content (low, high and very high nucleic acid contents labelled LNA, HNA and VHNA, respectively. Statistical analyses performed on the data set showed that LNA, mainly associated with low temperature and low salinity, were dominant in all the hydrological regions. In contrast, HNA distribution seemed to be associated with temperature, salinity, Chl a and silicic acid. A latitudinal increase in the HNA / LNA ratio was observed along the north–south transect and was related to higher phosphate and nitrate concentrations. However, the opposite relationship observed for the VHNA / HNA ratio suggested that the link between nucleic acid content and oligotrophic conditions is not linear, underlying the complexity of the biodiversity in the VHNA, HNA and LNA subgroups. In the Kuroshio Current, it is suggested that the high concentration of heterotrophic prokaryotes observed at station 4 was linked to the path of the cold cyclonic eddy core. In contrast, it is thought that low concentrations of heterotrophic prokaryotes in the warm core of the anticyclonic gyre (Sta. 9 are related to the low nutrient concentrations measured in the seawater column. Our results showed that the high variability between the various heterotrophic prokaryote cluster

  11. Climatological analysis of passage-type tropical cyclones from the Western North Pacific into the South China Sea

    Directory of Open Access Journals (Sweden)

    Jau-Ming Chen

    2017-01-01

    Full Text Available Tropical cyclone (TC climatological characteristics with passage from the Western North Pacific (WNP into the South China Sea (SCS during the June - November season are analyzed in this study. These TCs tend to form in the WNP west of 150°E, and on average westward by 7 - 12° in longitude than TCs that do not track into the SCS. Their formation locations migrate with the monsoon trough, moving northward from June to August, and southward from September to November. The probability of a WNP TC moving into the SCS varies seasonally, with only 12 - 18% of the WNP TCs doing so during August-September due to more northern TC formation. However, this probability rises to 25 - 26% in June - July and 25 - 32% in October - November with more southern TC formation. The passage-type TCs generally form in the eastern part of an elongated lower-level cyclonic anomaly of the 10-day low-pass filtered environmental circulation in the 10 - 20°N zone, which is paired with an anticyclonic anomaly to the north. Between this circulation pair, anomalous easterly flows steer these TCs westward, giving them a westward track into the SCS. The formation of these passage-type TCs is associated with a southward displacement of the monsoon trough and a westward intensification of the Pacific subtropical high in August and September. During June - July (October - November, the associated features appear as a southeastward (meridional expansion of the monsoon trough and a northward displacement of the Pacific subtropical high.

  12. From the subtropics to the equator in the Southwest Pacific: Continental material fluxes quantified using neodymium data along modeled thermocline water pathways

    Science.gov (United States)

    Grenier, Mélanie; Jeandel, Catherine; Cravatte, Sophie

    2014-06-01

    The southwestern tropical Pacific, part of a major pathway for waters feeding the Equatorial Undercurrent, is a region of important geochemical enrichment through land-ocean boundary exchange. Here we develop an original method based on the coupling between dynamical modeling and geochemical tracer data to identify regions of enrichment along the water pathways from the subtropics to the equator, and to allow a refined quantification of continental material fluxes. Neodymium data are interpreted with the help of modeled Lagrangian trajectories of an Ocean General Circulation Model. We reveal that upper and lower thermocline waters have different pathways together with different geochemical evolutions. The upper thermocline waters entering the Solomon Sea mainly originate from the central subtropical gyre, enter the Coral Sea in the North Vanuatu Jet and likely receive radiogenic neodymium from the basaltic island margins encountered along their route. The lower thermocline waters entering the Solomon Sea mainly originate from northeast of New Zealand and enter the Coral Sea in the North Caledonian Jet. Depletion of their neodymium content likely occurs when flowing along the Australian and Papua coasts. Downstream from the Solomon Sea, waters flowing along the Papua New Guinea margins near the Sepik river mouth become surprisingly depleted in their neodymium content in the upper thermocline while enriched in the lower thermocline. This coupled approach is proposed as strong support to interpret the origin of the equatorial Pacific natural fertilization through a better understanding of the circulation, important objectives of the international GEOTRACES and SPICE programs, respectively.

  13. Oceanographic profile temperature, salinity and other measurements collected using bottle from the SNP-1 in the Coastal South Pacific and South Pacific in 1976 (NODC Accession 0001483)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile, nutrients, and meteorological data were collected using bottle casts from the SNP-1 in the South Pacific Ocean. Data were collected from 24...

  14. Reconstruction of the springtime East Asian Subtropical Jet and Western Pacific pattern from a millennial-length Taiwanese tree-ring chronology

    Science.gov (United States)

    Wright, W. E.; Guan, B. T.; Tseng, Y.-H.; Cook, E. R.; Wei, K.-Y.; Chang, S.-T.

    2015-03-01

    The East Asian subtropical jet (EAJ) and the closely related Western Pacific pattern (WP) are among the most important features in global atmospheric dynamics, but little is known about their long-term variability. This study presents reconstructions of the Spring EAJ index (EAJI) and the Spring WP index (WPI) based on significant relationships identified between mean values for these features and a millennial length tree-ring width chronology of Chamaecyparis obtusa var. formosana, a high-mountain cloud forest species from northeastern Taiwan. Tree-ring based reconstructions of high pass filtered versions of the EAJI and WPI (EAJI 5YR and WPI 5YR) presented herein explain 42 and 31 % of the WPI 5YR and EAJI 5YR, respectively, and display acceptable reliability back to A.D. 1237. A significant trend present in the long-term variance of the reconstructed EAJI and WPI after A.D. 1860 suggests long-term increasing variability in the spring mean latitudinal placement and/or the strength/breadth of the EAJ core region near Taiwan and Japan and in the trajectory of the EAJ over the North Pacific. Related features affected by changes in the EAJ include the North Pacific storm track and Asian Dust transport.

  15. Mechanisms of P* reduction in the eastern tropical South Pacific

    DEFF Research Database (Denmark)

    Meyer, Judith; Löscher, Carolin R.; Lavik, Gaute

    2017-01-01

    for nitrogen fixing organisms. In order to assess the effect of low inorganic nutrient ratios on the stoichiometry and composition of primary producers, biogeochemical measurements were carried out in 2012 during a research cruise in the eastern tropical South Pacific (ETSP). Based on pigment analyses...... Redfield proportions throughout the sampling area, the stoichiometry of particulate organic nitrogen to phosphorus (PON:POP) generally exceeded ratios of 16:1. Despite PON:POP ≥ 16, high P*-values in the surface layer (0-50 m) above the shelf rapidly decreased as water masses were advected offshore....... There are three mechanisms which can explain these observations: (1) non-Redfield primary production, where the excess phosphorus in the biomass is directly released as dissolved organic phosphorus (DOP), (2) non-Redfield primary production, which is masked by a particulate organic matter pool mainly consisting...

  16. Ageing in the South Pacific. Physical changes with urbanization.

    Science.gov (United States)

    Finau, S A; Prior, I A; Evans, J G

    1982-01-01

    The process of ageing, the place the elderly hold in the South Pacific societies and the care they receive as they move from adult independence to geriatric dependence varies considerably in different Pacific Polynesian populations. This provides unusual opportunity to examine the physical changes of ageing in people of the same broad genetic make-up exposed to environmental changes brought about by urbanization. Epidemiological surveys carried out since 1962 among New Zealand Maoris, Tongans, Cook Island Maoris in Rarotonga and Pukapuka, and Tokelauans living in Tokelau and following migration to New Zealand, provide the main data base for this presentation. The pattern of blood pressure, body weight, serum lipids and clinical disorders show considerable variation which relate most closely to the adoption of westernized life-style and moving into an urban environment. Analysis of the ECG pattern, in Pukapukans, in whom blood pressure shows only a minor increase with age, compared with age and sex-matched subjects studied in Newcastle, England provide insights into the ageing heart. An examination of mortality based on risk factors at entry shows an inverse relationship of serum cholesterol to total mortality in New Zealand Maori men and women, in Tokelau men but not women. Increasing systolic blood pressure was related to mortality in New Zealand Maori men, Tokalau men and Caucasian women, but not in the other race sex groups. The pattern of ageing and risk factors must clearly be examined in individual populations because while death is the end the pathways vary.

  17. On the formation of the South Pacific quadrupole mode

    Science.gov (United States)

    Zheng, Jian; Wang, Faming

    2017-10-01

    The formation process of the South Pacific (SP) quadrupole (SPQ) mode was investigated in this study based on observations and reanalysis data. The SPQ is the dominant mode of the sea surface temperature (SST)-surface wind covariability in the SP after removing the ENSO-related signals. The positive phase of the SPQ is characterized by a warm SST anomaly (SSTA) west of the South American coast, a cool SSTA in its southwest, a positive SSTA southeast of New Zealand, and a negative SSTA off the southeast coast of Australia, overlain by cyclonic wind anomalies. The anomalous cyclonic winds weaken the mean southeast trade winds in the southeast SP and the westerlies in the high latitudes of the SP, increasing the SSTAs at the two positive poles through decreased evaporation and latent heat flux (LHF) loss. The southeast wind anomalies advect dry and cold air to the negative pole in the central SP, which reduces the SSTA there by increasing the LHF loss. Off the southeast coast of Australia, the southwest wind anomalies induce equatorward Ekman currents and advect cold water. The resulting oceanic horizontal advection is the main contributor to the negative SSTAs there. In addition to the above processes, cloud cover change can enhance the initial SSTAs in the southeast SP by affecting shortwave radiation. The decay of the SPQ is mainly due to LHF changes.

  18. ENSO regimes and the late 1970's climate shift: The role of synoptic weather and South Pacific ocean spiciness

    Energy Technology Data Exchange (ETDEWEB)

    O' Kane, Terence J.; Matear, Richard J.; Chamberlain, Matthew A.; Oke, Peter R.

    2014-08-15

    South Pacific subtropical density compensated temperature and salinity (spiciness) anomalies are known to be associated with decadal equatorial variability, however, the mechanisms by which such disturbances are generated, advect and the degree to which they modulate the equatorial thermocline remains controversial. During the late 1970's a climate regime transition preceded a period of strong and sustained El Nino events. Using an ocean general circulation model forced by the constituent mechanical and thermodynamic components of the reanalysed atmosphere we show that the late 1970's transition coincided with the arrival of a large-scale, subsurface cold and fresh water anomaly in the central tropical Pacific. An ocean reanalysis for the period 1990–2007 that assimilates subsurface Argo, XBT and CTD data, reveals that disturbances occur due to the subduction of negative surface salinity anomalies from near 30° S, 100° W which are advected along the σ=25–26 kgm{sup −3} isopycnal surfaces. These anomalies take, on average, seven years to reach the central equatorial Pacific where they may substantially perturb the thermocline before the remnants ultimately ventilate in the region of the western Pacific warm pool. Positive (warm–salty) disturbances, known to occur due to late winter diapycnal mixing and isopycnal outcropping, arise due to both subduction of subtropical mode waters and subsurface injection. On reaching the equatorial band (10° S–0° S) these disturbances tend to deepen the thermocline reducing the model's ENSO. In contrast the emergence of negative (cold–fresh) disturbances at the equator are associated with a shoaling of the thermocline and El Nino events. Process studies are used to show that the generation and advection of anomalous density compensated thermocline disturbances critically depend on stochastic forcing of the intrinsic ocean by weather. We further show that in the absence of the inter-annual component of

  19. Biological N2O fixation in the Eastern South Pacific Ocean and marine cyanobacterial cultures.

    Directory of Open Access Journals (Sweden)

    Laura Farías

    Full Text Available Despite the importance of nitrous oxide (N2O in the global radiative balance and atmospheric ozone chemistry, its sources and sinks within the Earth's system are still poorly understood. In the ocean, N2O is produced by microbiological processes such as nitrification and partial denitrification, which account for about a third of global emissions. Conversely, complete denitrification (the dissimilative reduction of N2O to N2 under suboxic/anoxic conditions is the only known pathway accountable for N2O consumption in the ocean. In this work, it is demonstrated that the biological assimilation of N2O could be a significant pathway capable of directly transforming this gas into particulate organic nitrogen (PON. N2O is shown to be biologically fixed within the subtropical and tropical waters of the eastern South Pacific Ocean, under a wide range of oceanographic conditions and at rates ranging from 2 pmol N L(-1 d(- to 14.8 nmol N L(-1 d(-1 (mean ± SE of 0.522 ± 1.06 nmol N L(-1 d(-1, n = 93. Additional assays revealed that cultured cyanobacterial strains of Trichodesmium (H-9 and IMS 101, and Crocosphaera (W-8501 have the capacity to directly fix N2O under laboratory conditions; suggesting that marine photoautotrophic diazotrophs could be using N2O as a substrate. This metabolic capacity however was absent in Synechococcus (RCC 1029. The findings presented here indicate that assimilative N2O fixation takes place under extreme environmental conditions (i.e., light, nutrient, oxygen where both autotrophic (including cyanobacteria and heterotrophic microbes appear to be involved. This process could provide a globally significant sink for atmospheric N2O which in turn affects the oceanic N2O inventory and may also represent a yet unexplored global oceanic source of fixed N.

  20. The South Pacific in the works of Robert Dean Frisbie

    Directory of Open Access Journals (Sweden)

    Nataša Potočnik

    2001-12-01

    In Tahiti he had ambitious writing plans but after four years of living in Tahiti, he left his plantation and sailed to the Cook Islands. He spent the rest of his life in the Cook Islands and married a local girl Ngatokorua. His new happiness gave him the inspiration to write. 29 sketches appeared in the United States in 1929, collected by The Century Company under the title of The Book of Puka-Puka. His second book My Tahiti, a book of memories, was published in 1937. After the death of Ropati 's beloved wife his goals were to bring up his children. But by this time Frisbie was seriously ill. The family left Puka-Puka and settled down on the uninhabited atoll of Suwarrow. Later on they lived on Rarotonga and Samoa where Frisbie was medically treated. Robert Dean Frisbie died of tetanus in Rarotonga on November 18, 1948. Frisbie wrote in a vivid, graceful style. His characters and particularly the atoll of Puka-Puka are memorably depicted. Gifted with a feeling for language and a sense of humor, he was able to capture on paper the charm, beauty, and serenity of life of the small islands in the South Pacific without exaggerating the stereotypical idyllic context and as such Frisbie's contribution to South Pacific literature went far deeper than that of many writers who have passed through the Pacific and wrote about their experiences. Frisbie's first book The Book of Puka-Puka was published in New York in 1929. It is the most endearing and the most original of his works. It was written during his lifetime on the atoll Puka-Puka in the Cook Islands. It is a collection of 29 short stories, episodic and expressively narrative in style. This is an account of life on Puka-Puka that criticizes European and American commercialism and aggressiveness, and presents the themes of the praise of isolation, the castigation of missionaries, and the commendation of Polynesian economic collectivism and sexual freedom. At the same time, the book presents a portrait of Frisbie himself

  1. 10m Gridded bathymetry of Swains Island, American Samoa, South Pacific (netCDF format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (10 m cell size) bathymetry of the slope environment of Swains Island, American Samoa, South Pacific. Almost complete bottom coverage was achieved in depths...

  2. 10 m Gridded bathymetry of Swains Island, American Samoa, South Pacific (Arc ASCII format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (10 m cell size) bathymetry of the slope environment of Swains Island, American Samoa, South Pacific. Almost complete bottom coverage was achieved in depths...

  3. Collection of Groundwater and Freshwater Fauna on the Islands of the South Pacific. Operation Raleigh -- Pacific Crossing

    NARCIS (Netherlands)

    Broodbakker, Nico W.

    1988-01-01

    During this project about 150 groundwater habitats were sampled on a number of islands in the South Pacific. The main habitats sampled were: wells, springs, caves, beaches and streams. Groundwater fauna was only found on two islands. On Easter Island we found a new species belonging to the Isopoda

  4. Flow structure and variability in the subtropical Indian Ocean: instability of the South Indian Ocean countercurrent

    NARCIS (Netherlands)

    Palastanga, V.|info:eu-repo/dai/nl/313947112; van Leeuwen, P.J.|info:eu-repo/dai/nl/102655758; Schouten, M.W.; de Ruijter, W.P.M.|info:eu-repo/dai/nl/068476760

    2007-01-01

    The origin of the eddy variability around the 25 S band in the Indian Ocean is investigated. We have found that the surface circulation east of Madagascar shows an anticyclonic subgyre bounded to the south by eastward flow from southwest Madagascar, and to the north by the westward flowing South

  5. Microbial diversity and stratification of South Pacific abyssal marine sediments.

    Science.gov (United States)

    Durbin, Alan M; Teske, Andreas

    2011-12-01

    Abyssal marine sediments cover a large proportion of the ocean floor, but linkages between their microbial community structure and redox stratification have remained poorly constrained. This study compares the downcore gradients in microbial community composition to porewater oxygen and nitrate concentration profiles in an abyssal marine sediment column in the South Pacific Ocean. Archaeal 16S rRNA clone libraries showed a stratified archaeal community that changed from Marine Group I Archaea in the aerobic and nitrate-reducing upper sediment column towards deeply branching, uncultured crenarchaeotal and euryarchaeotal lineages in nitrate-depleted, anaerobic sediment horizons. Bacterial 16S rRNA clone libraries revealed a similar shift on the phylum and subphylum level within the bacteria, from a complex community of Alpha-, Gamma- and Deltaproteobacteria, Actinobacteria and Gemmatimonadetes in oxic surface sediments towards uncultured Chloroflexi and Planctomycetes in the anaerobic sediment column. The distinct stratification of largely uncultured bacterial and archaeal groups within the oxic and nitrate-reducing marine sediment column provides initial constraints for their microbial habitat preferences. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

  6. Holocene shifts of the Subtropical Shelf Front off southeastern South America controlled by high and low latitude atmospheric forcings

    Science.gov (United States)

    Bender, Vera B.; Hanebuth, Till J. J.; Chiessi, Cristiano M.

    2013-09-01

    Over the Uruguayan shelf and uppermost slope, the coalescence of northward flowing Subantarctic Shelf Water and southward flowing Subtropical Shelf Water forms a distinct thermohaline front termed the Subtropical Shelf Front (STSF). Running in a SW direction diagonally across the shelf from the coastal waters at 32°S toward the shelf break at ca. 36°S, the STSF represents the shelfward extension of the Brazil-Malvinas Confluence zone. This study reconstructs latitudinal STSF shifts during the Holocene based on benthic foraminifera δ18O and δ13C, total organic carbon, carbonate contents, Ti/Ca, and grain size distribution from a high-accumulation sedimentary record located at an uppermost continental-slope terrace. Our data provide direct evidence for: (1) a southern STSF position (to the South of the core site) at the beginning of the early Holocene (>9.4 cal ka BP) linked to a more southerly position of the Southern Westerly Winds in combination with restricted shelf circulation intensity due to lower sea level; (2) a gradual STSF northward migration (bypassing the core site toward the North) primarily forced by the northward migration of the Southern Westerly Winds from 9.4 cal ka BP onward; (3) a relatively stable position of the front in the interval between 7.2 and 4.0 cal ka BP; (4) millennial-scale latitudinal oscillations close to 36°S of the STSF after 4.0 cal ka BP probably linked to the intensification in El Niño Southern Oscillation; and (5) a southward migration of the STSF during the last 200 years possibly linked to anthropogenic influences on the atmosphere.

  7. The Use of PIES Data to Observe South Atlantic Subtropical Mode Water

    Science.gov (United States)

    Cortezi, M. V.; Sato, O. T.; Meinen, C. S.

    2016-02-01

    Subtropical mode water is a voluminous body of water in the ocean whose main feature is the homogeneity in both vertical structure and horizontal extension. The subtropical mode water (STMW) of the southwest Atlantic is formed between the months of July and October near the Brazil-Malvinas confluence and along the Brazil Current recirculation gyre. The formation region extends on the order of 3000 km zonally, from 20°W to 50°W, and 1000 km meridionally, from 30°S to 40°S , and it is typically about 170 m thick. In situ data from pressure-equipped inverted echo sounders (PIES) installed in the western portion of the basin, along 34.5°S, are available from 2009 to the present. These data when properly treated and calibrated can provide an unprecedented description of the STMW involving processes since its formation at the surface until the final stage of its residence in the interior of the ocean.Temperature and salinity data estimated by the PIES are based on an empirical look-up tables that relate the acoustic travel time with the baroclinic structure of the ocean. This technique is known as the Gravest Empirical Mode (GEM) method, and here it is used to recognize profiles containing homogeneous segments of temperature and salinity that characterize the mode water. From the easternmost mooring data of the PIES array, the STMW was detected below the surface at depths ranging between 150 m to 500 m, with a typical layer thickness of 140 m, and temperature range between 14.1 and 15.9°C and salinity between 35.4 and 35.8. The GEM method will further be adapted to help us detect the STMW in its formation stage. The main hypothesis to be tested in this study is that variations at interannual scale in the formation of STMW are linked to variations in the intensity of its interaction with the Brazil Current.

  8. Paleoceanography in Pelagic Clay of the South Pacific Gyre

    Science.gov (United States)

    Dunlea, A. G.; Murray, R. W.; Sauvage, J.; Spivack, A. J.; Harris, R. N.; D'Hondt, S.

    2014-12-01

    A spatially and temporally expansive record of early Cenozoic high-latitude ocean history resides in the pelagic clay of the South Pacific Gyre (SPG). At the beginning of the Cenozoic, four sites drilled during IODP Expedition 329 were located between 40-62°S, which may have been the center of an ancient polar gyre. As the Pacific Plate migrated northward, these sites were subjected to major paleoceanographic changes including the onset of the Antarctic Circumpolar Current, Australian desertification, and Southern Hemisphere volcanism. The SPG sediment is homogenous brown, zeolitic, metalliferous pelagic clay. Such sediment can be challenging for paleooceanographic research due its ultrafine grain size, slow accumulation rate, post-depositional alteration, and lack of biogenic material. However, our geochemical techniques embrace the authigenic nature of SPG clay to develop a constant-Co age model and track variations in sediment origin and accumulation. By combining sedimentation patterns with backtracked site paths, we produce an unprecedented characterization of the Cenozoic paleoceanographic evolution of the SPG. We analyzed 47 major, trace, REE concentrations in 206 bulk sediment samples from 7 sites across the SPG, deposited as long ago as 100 Ma. For each sample, traditional geochemical partitioning techniques, Q-mode factor analyses, and multiple linear regressions allowed us to quantify contributions of six end-members: post-Archean average Australian shale (PAAS), Fe-Mn-oxyhydroxides, apatite, biogenic Si, and two distinct types of altered volcanic ash. Mass accumulation of the PAAS end-member increased 12-18% throughout the Cenozoic, with the most rapid increase occurring just after the mid-Miocene when Australia became more arid. The Paleogene/Neogene boundary also marks a change in sedimentation, likely caused by a change in eolian activity and/or a change in authigenic processes due to changing bottom water conditions. Contributions from one kind of

  9. Metabolic activity of subseafloor microbes in the South Pacific Gyre

    Science.gov (United States)

    Morono, Y.; Ito, M.; Terada, T.; Inagaki, F.

    2013-12-01

    The South Pacific Gyre (SPG) is characterized as the most oligotrophic open ocean environment. The sediment is rich in oxygen but poor in energy-sources such as reduced organic matter, and hence harbors very low numbers of microbial cells in relatively shallow subseafloor sediment (D'Hondt et al., 2009; Kallmeyer et al., 2012). In such an energy-limited sedimentary habitat, a small size of microbial community persists living functions with extraordinary low oxygen-consumption rate (Røy et al., 2012). During IODP Expedition 329, a series of sediment samples were successfully recovered from 7 drill sites (U1365-1371) from the seafloor to basement in the SPG, providing an unprecedented opportunity to study metabolic activity of the aerobic subseafloor microbial communities. We initiated incubation onboard by adding stable isotope-labeled substrates to the freshly collected sediment sample, such as 13C and/or 15N-labeled bicarbonate, glucose, amino acids, acetate, and ammonium under the (micro-) aerobic condition. One of the technological challenges in this study is to harvest microbial cells from very low-biomass sediment samples for the analysis using nano-scale secondary ion mass spectrometry (NanoSIMS). To address the technical issue, we improved existing cell separation technique for the SPG sediment samples with small inorganic zeolitic grains. By monitoring cell recovery rates through an image-based cell enumeration technique (Morono et al., 2009), we found that cell recovery rates in the SPG sediment samples are generally lower than those in other oceanographic settings (i.e., organic-rich ocean margin sediments). To gain higher cell recovery ratio, we applied multiple density gradient layers, resulting in the cell recovery ratio up to around 80-95% (Morono et al., in press). Then, using the newly developed cell separation technique, we successfully sorted enough number of microbial cells in small spots on the membrane (i.e., 103 to 105 cells per spot). Nano

  10. Calcite production by coccolithophores in the south east Pacific Ocean

    Directory of Open Access Journals (Sweden)

    L. Beaufort

    2008-08-01

    Full Text Available BIOSOPE cruise covered an oceanographic transect through the centre of the South Pacific Gyre (SPG from the Marquesas archipelago to the Peru-Chile upwelling (PCU. Water samples from 6 depths in the euphotic zone were collected at 20 stations. The concentrations of suspended calcite particles, coccolithophores cells and detached coccoliths were estimated together with size and weight using an automatic polarizing microscope, a digital camera, and a collection of softwares performing morphometry and pattern recognition. Some of these softwares are new and described here for the first time. The coccolithophores standing stocks were usually low and reached maxima west of the PCU. The coccoliths of Emiliania huxleyi, Gephyrocapsa spp. and Crenalithus spp. (Order Isochrysidales represented more than 30% of all the suspended calcite particles detected in the size range 0.1–46 μm (22% of PIC in term of calcite weight. These species grew preferentially in the Chlorophyll maximum zone. In the SPG their maximum cell concentrations were recorded between depth of 150 and 200 m, which is unusually deep for these taxa. The weight of coccoliths and coccospheres were correlated to their size. Large and heavy coccoliths and coccospheres were found in regions with relatively high fertility in the Marquises Island and in the PCU. Small and light coccoliths and coccospheres were found west of the PCU. This distribution is strongly related to ocean chemistry in particular to alkalinity and to carbonate ions concentration. The biotic (coccolithophores production influence on calcification is mainly driven at the local scale (depth whereas the abiotic (carbonate chemistry plays its most important role at the regional (horizontal level. Here 94% of the variability of coccolith and coccosphere weight can be explained by a change in 7 environmental variables.

  11. Ecological patterns, distribution and population structure of Prionace glauca (Chondrichthyes: Carcharhinidae) in the tropical-subtropical transition zone of the north-eastern Pacific.

    Science.gov (United States)

    Vögler, Rodolfo; Beier, Emilio; Ortega-García, Sofía; Santana-Hernández, Heriberto; Valdez-Flores, J Javier

    2012-02-01

    Regional ecological patterns, distribution and population structure of Prionace glauca were analyzed based on samples collected on-board two long-line fleets operating in oceanic waters (1994-96/2000-02) and in coastal oceanic waters (2003-2009) of the eastern tropical Pacific off México. Generalized additive models were applied to catch per unit of effort data to evaluate the effect of spatial, temporal and environmental factors on the horizontal distribution of the life stages (juvenile, adult) and the sexes at the estimated depth of catch. The presence of breeding areas was explored. The population structure was characterized by the presence of juveniles' aggregations and pregnant females towards coastal waters and the presence of adult males' aggregations towards oceanic waters. The species exhibited horizontal segregation by sex-size and vertical segregation by sex. Distribution of the sex-size groups at oceanic waters was seasonally affected by the latitude; however, at coastal oceanic waters mainly females were influenced by the longitude. Latitudinal changes on the horizontal distribution were coupled to the seasonal forward and backward of water masses through the study area. Adult males showed positive relationship with high temperatures and high-salinities waters (17.0°-20.0 °C; 34.2-34.4) although they were also detected in low-salinities waters. The distribution of juvenile males mainly occurred beyond low temperatures and low-salinities waters (14.0°-15.0 °C; 33.6-34.1), suggesting a wide tolerance of adult males to explore subartic and subtropical waters. At oceanic areas, adult females were aggregated towards latitudes distribution of juvenile females indicated its preference by lower temperatures and more saline waters. Presence of pregnant females suggests that the eastern tropical Pacific off México represents an ecological key region to the reproductive cycle of P. glauca. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. [Soil microbial community structure of monoculture and mixed plantation stands of native tree species in south subtropical China].

    Science.gov (United States)

    Luo, Da; Shi, Zuo-Min; Tang, Jing-Chao; Liu, Shi-Rong; Lu, Li-Hua

    2014-09-01

    The effects of three plantation stands, Erythrophleumf ordii (EF), Pinus massoniana (PM), and their mixed plantation (MP), on soil microbial biomass and microbial community structure in south subtropical China were studied by the method of phospholipid fatty acids (PLFAs) analysis. The results showed that the amounts of microbial total PLFAs and PLFAs of each microbial group in these three plantation stand soils were significantly higher in dry season than in rainy season. In dry season, the amounts of microbial total PLFAs, bacteria PLFAs, fungi PLFAs, and actinomycetes PLFAs were the highest in the PM soil, moderate in the MP soil, and the lowest in the EF soil. But in rainy season, the amounts of microbial total PLFAs, bacteria PLFAs, fungi PLFAs, and arbuscular mycorrhizal fungi (AMF) PLFAs in the EF soil were higher than in the MP soil, and were significantly higher than in the PM soil. Principal component analysis (PCA) indicated that the variations in soil microbial community structure composition were affected by both plantation types and seasons. Redundancy analysis (RDA) of soil microbial community structure and environmental factors showed that soil temperature and moisture, pH, total nitrogen content, and ammonium nitrogen content had significant correlations with PLFA signatures. In addition, the ratio of fungi PLFAs to bacteria PLFAs in the MP soil was the highest among the three stand soils within the whole year, indicating that mixed plantation stands could facilitate the stability of the soil ecosystem.

  13. Long-Term Changes in the Water Quality and Macroinvertebrate Communities of a Subtropical River in South China

    Directory of Open Access Journals (Sweden)

    Kun Li

    2014-12-01

    Full Text Available Subtropical rivers support a highly diverse array of benthic macroinvertebrates. In this study, by combining historical data and new data, we identified specific changes in the Guanlan River, in South China, from 1981 to 2011, and evaluated the effectiveness of an ecological restoration project under highly polluted conditions. From 1981 to 2011, the water quality in the Guanlan River underwent three major stages. With the deterioration of water quality, there was an overall decrease in the species number of macroinvertebrates in the Guanlan River, an increase in macroinvertebrate density, and a reduction of the biodiversity, and a reduction of functional feeding groups. In 2011, after five years of comprehensive remediation, the Guanlan River was somewhat improved. Macroinvertebrate biodiversity in the middle reach of the Guanlan River, where a key ecological restoration engineering project was implemented, did not differ significantly from other sites. This finding indicates that the effectiveness of ecological restoration measures in highly polluted rivers, particularly at the reach-scale, is very limited and even ineffective.

  14. Using mercury isotopes to understand the bioaccumulation of Hg in the subtropical Pearl River Estuary, South China.

    Science.gov (United States)

    Yin, Runsheng; Feng, Xinbin; Zhang, Junjun; Pan, Ke; Wang, Wenxiong; Li, Xiangdong

    2016-03-01

    Coastal and estuarine regions are important areas of mercury pollution. Therefore, it is important to properly characterize the sources and bioaccumulation processes of mercury in these regions. Here, we present mercury stable isotopic compositions in 18 species of wild marine fish collected from the Pearl River Estuary (PRE), south China. Our results showed variations in mass-independent fractionation (Δ(199)Hg: +0.05 ± 0.10‰ to +0.59 ± 0.30‰) with a Δ(199)Hg/Δ(201)Hg of ∼1.26, suggesting that aqueous MeHg underwent photo-degradation prior to incorporation into the food chain. For the results, we discovered small but significant differences of Δ(199)Hg values among herbivorous, demersal, and carnivorous fish, indicating that different feeding guilds of fish may have incorporated MeHg with various degrees of photo-demethylation. The consistent mercury isotope compositions between fish feeding habitat and mercury sources in the estuary provide potentially important findings on the transformation and bioaccumulation of this toxic metal in subtropical coastal environments. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Contrasting patterns of phytoplankton pigments and chemotaxonomic groups along 30°S in the subtropical South Atlantic Ocean

    Science.gov (United States)

    Araujo, Milton Luiz Vieira; Mendes, Carlos Rafael Borges; Tavano, Virginia Maria; Garcia, Carlos Alberto Eiras; Baringer, Molly O'Neil

    2017-02-01

    This work describes the spatial distribution of pigments and main taxonomic groups of phytoplankton in the biogeochemical provinces of the subtropical South Atlantic Ocean, along 30°S latitude. Seawater samples (surface to 200 m depth) were collected along 120 oceanographic stations occupied in the early austral spring of 2011, during a CLIVAR Repeat Hydrography cruise. The pigments were identified and quantified by high performance liquid chromatography (HPLC), and CHEMTAX software was used to determine the relative contributions of the main taxonomic groups to total chlorophyll a (phytoplankton biomass index). Sampling stations were grouped into three provinces: Africa, Gyre, and Brazil, corresponding to the eastern, central, and western sectors of the transect, respectively. Our results showed that both vertical and horizontal distribution patterns of pigments and taxonomic groups were mainly determined by the availability of light and/or nutrients. Photosynthetic carotenoids (PSCs), associated with small flagellates (mainly haptophytes), dominated the light-limited and nutrient-enhanced deep chlorophyll maximum (DCM) layers of both the Brazil and Gyre provinces, as well as the upwelling influenced surface waters of the Africa province. The latter showed the highest chlorophyll a values ​​(>1 mg m-3) and abundance of dinoflagellates in the coastal region. Photoprotective carotenoids (PPCs) were predominant in the nutrient-poor and well-lit surface layers of the Brazil and Gyre provinces, associated with a low content of chlorophyll a ( 0.1 mg m-3) and dominance of prokaryotes (Synechoccocus and Prochloroccocus). This study demonstrates that pigment analysis can provide a useful approach to better understand the distribution of phytoplankton communities along physical-chemical gradients in a still undersampled region of the South Atlantic Ocean.

  16. Description of the biogeochemical features of the subtropical southeastern Atlantic and the Southern Ocean south of South Africa during the austral summer of the International Polar Year

    Science.gov (United States)

    Le Moigne, F. A. C.; Boye, M.; Masson, A.; Corvaisier, R.; Grossteffan, E.; Guéneugues, A.; Pondaven, P.

    2013-01-01

    Meridional and vertical distributions of several biogeochemical parameters were studied along a section in the southeastern Atlantic and the Southern Ocean south of South Africa during the austral summer 2008 of the International Polar Year to characterize the biogeochemical provinces and to assess the seasonal net diatom production. Based on analyses of macro-nutrients, ammonium (NH4), chlorophyll a, (Chl a), phaeopigments, biogenic silica (BSi), particulate inorganic carbon (PIC), and particulate organic carbon and nitrogen (POC and PON, respectively), four biogeochemical domains were distinguished along the section: the subtropical Atlantic, the confluence zone of the subtropical and subantarctic domains, the Polar Frontal Zone (PFZ) in the Antarctic Circumpolar Current (ACC), and the north-eastern branch of the Weddell Gyre. The subtropical region displayed extremely low nutrient concentrations featuring oligotrophic conditions, and sub-surface maxima of Chl a and phaeopigments never exceeded 0.5 µg L-1 and 0.25 µg L-1, respectively. The anticyclonic and cyclonic eddies crossed in the Cape Basin were characterized by a deepening and a rise, respectively, of the nutrients isoclines. The confluence zone of the subtropical domain and the northern side of the ACC within the subantarctic domain displayed remnant nitrate and phosphate levels, whereas silicate concentrations kept to extremely low levels. In this area, Chl a level of 0.4-0.5 µg L-1 distributed homogenously within the mixed layer, and POC and PON accumulated to values up to 10 µM and 1.5 µM, respectively, indicative of biomass accumulation along the confluence zone during the late productive period. In the ACC domain, the Polar Frontal Zone was marked by a post-bloom of diatoms that extended beyond the Polar Front (PF) during this late summer condition, as primarily evidenced by the massive depletion of silicic acid in the surface waters. The accumulation of NH4 to values up to 1.25 µM at 100 m

  17. Description of the biogeochemical features of the subtropical southeastern Atlantic and the Southern Ocean south of South Africa during the austral summer of the International Polar Year

    Directory of Open Access Journals (Sweden)

    F. A. C. Le Moigne

    2013-01-01

    Full Text Available Meridional and vertical distributions of several biogeochemical parameters were studied along a section in the southeastern Atlantic and the Southern Ocean south of South Africa during the austral summer 2008 of the International Polar Year to characterize the biogeochemical provinces and to assess the seasonal net diatom production. Based on analyses of macro-nutrients, ammonium (NH4, chlorophyll a, (Chl a, phaeopigments, biogenic silica (BSi, particulate inorganic carbon (PIC, and particulate organic carbon and nitrogen (POC and PON, respectively, four biogeochemical domains were distinguished along the section: the subtropical Atlantic, the confluence zone of the subtropical and subantarctic domains, the Polar Frontal Zone (PFZ in the Antarctic Circumpolar Current (ACC, and the north-eastern branch of the Weddell Gyre. The subtropical region displayed extremely low nutrient concentrations featuring oligotrophic conditions, and sub-surface maxima of Chl a and phaeopigments never exceeded 0.5 µg L−1 and 0.25 µg L−1, respectively. The anticyclonic and cyclonic eddies crossed in the Cape Basin were characterized by a deepening and a rise, respectively, of the nutrients isoclines. The confluence zone of the subtropical domain and the northern side of the ACC within the subantarctic domain displayed remnant nitrate and phosphate levels, whereas silicate concentrations kept to extremely low levels. In this area, Chl a level of 0.4–0.5 µg L−1 distributed homogenously within the mixed layer, and POC and PON accumulated to values up to 10 µM and 1.5 µM, respectively, indicative of biomass accumulation along the confluence zone during the late productive period. In the ACC domain, the Polar Frontal Zone was marked by a post-bloom of diatoms that extended beyond the Polar Front (PF during this late summer condition, as primarily evidenced by the massive depletion of

  18. Oceanographic profile temperature, salinity, oxygen and other measurement collected from various platforms in the South Pacific and South Atlantic Oceans from 1961-1964 (NODC Accession 0001903)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile and nutrients data were collected using bottle casts from the ARGUS in the South Atlantic Ocean and South Pacific Ocean. Data were collected from...

  19. Understanding Abrupt, Natural Climate Variability Post-Industrial Revolution from the Subtropical Eastern Pacific: A Novel High Resolution Alkenone-derived Sea Surface Temperature Record

    Science.gov (United States)

    Kelly, C. S.; O'Mara, N. A.; Herbert, T.; Abella-Gutiérrez, J. L.; Herguera, J. C.

    2015-12-01

    Despite the ocean's importance in global biogeochemical feedbacks and heat storage, there is still a paucity of decadally-resolved sea surface temperature (SST) records to complement lacustrine and dendrological records of recent paleoclimate. Natural climate variability on multidecadal timescales is dominated by internal ocean circulation dynamics and feedbacks, and it is therefore imperative to employ marine proxies to reconstruct high resolution climate change. The timescales of this ocean-induced natural climate variability can be broken down into a few characteristic climate modes. Pressing questions about these modes include their stationarity in frequency and amplitude over time, in addition to the hypothesis that anthropogenic climate change has altered their behavior in comparison to natural variability. To pursue these questions, we must discern and analyze suitable climate archives in regions where modes of interest dominate modern climate variability. The region of Baja California, Mexico exhibits exceptional teleconnection to the El Niño Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO). Local, dramatic effects of ENSO and PDO on the marine biology and economy underline the importance of regional paleoclimate records from the Baja peninsula. Here, we present a high-resolution alkenone-derived SST reconstruction from the Industrial Revolution through the year 2000 by analysis of laminated box and Kasten sediment cores at Site PCM 00-78 (25.18°N, 112.66°W) in the subtropical eastern Pacific at a depth of 540 meters. Our SST record corresponds with NOAA extended reconstructed sea surface temperature, providing a robust basis for organic geochemical marine climatic reconstructions on timescales usually accessible only through speleothems, coral density bands, tree rings, and the like. Accordingly, based on this comparison to the historical data we expect our SST record may provide a more robust record of inter and multidecadal

  20. Interannual variability of the South Pacific Convergence Zone and implications for tropical cyclone genesis

    Energy Technology Data Exchange (ETDEWEB)

    Vincent, Emmanuel M. [IRD/UPMC/CNRS/MNHN, Laboratoire d' Oceanographie et du Climat: Experimentation et Approches Numeriques (LOCEAN), Paris (France); UPMC, LOCEAN/IPSL, Paris Cedex 05 (France); Lengaigne, Matthieu [IRD/UPMC/CNRS/MNHN, Laboratoire d' Oceanographie et du Climat: Experimentation et Approches Numeriques (LOCEAN), Paris (France); National Institute of Oceanography, Goa (India); Menkes, Christophe E. [IRD/UPMC/CNRS/MNHN, Laboratoire d' Oceanographie et du Climat: Experimentation et Approches Numeriques (LOCEAN), Paris (France); Institut de Recherche pour le Developpement, Noumea (New Caledonia); Jourdain, Nicolas C. [Institut de Recherche pour le Developpement, Noumea (New Caledonia); Marchesiello, Patrick [Institut de Recherche pour le Developpement, Noumea (New Caledonia); CNES/CNRS/UPS/IRD, Laboratoire d' Etudes en Geophysique et Oceanographie Spatiale (LEGOS), Toulouse (France); Madec, Gurvan [IRD/UPMC/CNRS/MNHN, Laboratoire d' Oceanographie et du Climat: Experimentation et Approches Numeriques (LOCEAN), Paris (France); National Oceanographic Centre, Southampton (United Kingdom)

    2011-05-15

    The interannual variability of the South Pacific Convergence Zone (SPCZ) and its influence on tropical cyclone (TC) genesis in the South Pacific are investigated using observations and ERA40 reanalysis over the 1979-2002 period. In austral summer, the SPCZ displays four typical structures at interannual timescales. The first three are characterized by a diagonal orientation of the SPCZ and account for 85% of the summer seasons. One is close to climatology and the other two exhibit a 3 northward or southward departure from the SPCZ climatological position. In contrast, the fourth one, that only encompasses three austral summer seasons (the extreme 1982/1983 and 1997/1998 El Nino events and the moderate 1991/1992 El Nino event), displays very peculiar behaviour where the SPCZ largely departs from its climatological position and is zonally oriented. Variability of the western/central Pacific equatorial sea surface temperature (SST) is shown to modulate moisture transport south of the equator, thereby strongly constraining the location of the SPCZ. The SPCZ location is also shown to strongly modulate the atmospheric circulation variability in the South Pacific with specific patterns for each class. However, independently of its wide year-to-year excursions, the SPCZ is always collocated with the zero relative vorticity at low levels while the maximum vorticity axis lies 6 to the south of the SPCZ position. This coherent atmospheric organisation in the SPCZ region is shown to constrain tropical cyclogenesis to occur preferentially within 10 south of the SPCZ location as this region combines all the large-scale atmospheric conditions that favour the breeding of TCs. This analysis also reveals that cyclogenesis in the central Pacific (in the vicinity of French Polynesia) only occurs when the SPCZ displays a zonal orientation while this observation was previously attributed to El Nino years in general. Different characteristics of El Nino Southern Oscillation (ENSO

  1. A dissolved cobalt plume in the oxygen minimum zone of the eastern tropical South Pacific

    Science.gov (United States)

    Hawco, Nicholas J.; Ohnemus, Daniel C.; Resing, Joseph A.; Twining, Benjamin S.; Saito, Mak A.

    2016-10-01

    Cobalt is a nutrient to phytoplankton, but knowledge about its biogeochemical cycling is limited, especially in the Pacific Ocean. Here, we report sections of dissolved cobalt and labile dissolved cobalt from the US GEOTRACES GP16 transect in the South Pacific. The cobalt distribution is closely tied to the extent and intensity of the oxygen minimum zone in the eastern South Pacific with highest concentrations measured at the oxycline near the Peru margin. Below 200 m, remineralization and circulation produce an inverse relationship between cobalt and dissolved oxygen that extends throughout the basin. Within the oxygen minimum zone, elevated concentrations of labile cobalt are generated by input from coastal sources and reduced scavenging at low O2. As these high cobalt waters are upwelled and advected offshore, phytoplankton export returns cobalt to low-oxygen water masses underneath. West of the Peru upwelling region, dissolved cobalt is less than 10 pM in the euphotic zone and strongly bound by organic ligands. Because the cobalt nutricline within the South Pacific gyre is deeper than in oligotrophic regions in the North and South Atlantic, cobalt involved in sustaining phytoplankton productivity in the gyre is heavily recycled and ultimately arrives from lateral transport of upwelled waters from the eastern margin. In contrast to large coastal inputs, atmospheric deposition and hydrothermal vents along the East Pacific Rise appear to be minor sources of cobalt. Overall, these results demonstrate that oxygen biogeochemistry exerts a strong influence on cobalt cycling.

  2. Hydrogen peroxide in deep waters from the Mediterranean Sea, South Atlantic and South Pacific Oceans

    Science.gov (United States)

    Hopwood, Mark J.; Rapp, Insa; Schlosser, Christian; Achterberg, Eric P.

    2017-03-01

    Hydrogen peroxide (H2O2) is present ubiquitously in marine surface waters where it is a reactive intermediate in the cycling of many trace elements. Photochemical processes are considered the dominant natural H2O2 source, yet cannot explain nanomolar H2O2 concentrations below the photic zone. Here, we determined the concentration of H2O2 in full depth profiles across three ocean basins (Mediterranean Sea, South Atlantic and South Pacific Oceans). To determine the accuracy of H2O2 measurements in the deep ocean we also re-assessed the contribution of interfering species to ‘apparent H2O2’, as analysed by the luminol based chemiluminescence technique. Within the vicinity of coastal oxygen minimum zones, accurate measurement of H2O2 was not possible due to interference from Fe(II). Offshore, in deep (>1000 m) waters H2O2 concentrations ranged from 0.25 ± 0.27 nM (Mediterranean, Balearics-Algeria) to 2.9 ± 2.2 nM (Mediterranean, Corsica-France). Our results indicate that a dark, pelagic H2O2 production mechanism must occur throughout the deep ocean. A bacterial source of H2O2 is the most likely origin and we show that this source is likely sufficient to account for all of the observed H2O2 in the deep ocean.

  3. Economic impacts of interregional competition in the forest products industry during the 1970's: the South and the Pacific Northwest.

    Science.gov (United States)

    Con H. Schallau; Wilbur R. Maki

    1986-01-01

    Until the 1970's, the Pacific Northwest dominated national markets for softwood lumber and plywood. During the 1970's, however, the region's share declined while production increased in the South. Meanwhile, the South's and the Pacific Northwest's shares of the Nation's employment in lumber and wood products declined. This resulted mainly...

  4. Source, composition, and environmental implication of neutral carbohydrates in sediment cores of subtropical reservoirs, South China

    Science.gov (United States)

    Duan, Dandan; Zhang, Dainan; Yang, Yu; Wang, Jingfu; Chen, Jing'an; Ran, Yong

    2017-09-01

    Neutral monosaccharides, algal organic matter (AOM), and carbon stable isotope ratios in three sediment cores of various trophic reservoirs in South China were determined by high-performance anion-exchange chromatography, Rock-Eval pyrolysis, and Finnigan Delta Plus XL mass spectrometry, respectively. The carbon isotopic compositions were corrected for the Suess effect. The concentrations of total neutral carbohydrates (TCHO) range from 0.51 to 6.4 mg g-1 at mesotrophic reservoirs, and from 0.83 to 2.56 mg g-1 at an oligotrophic reservoir. Monosaccharide compositions and diagnostic parameters indicate a predominant contribution of phytoplankton in each of the three cores, which is consistent with the results inferred from the corrected carbon isotopic data and C/N ratios. The sedimentary neutral carbohydrates are likely to be structural polysaccharides and/or preserved in sediment minerals, which are resistant to degradation in the sediments. Moreover, the monosaccharide contents are highly related to the carbon isotopic data, algal productivity estimated from the hydrogen index, and increasing mean air temperature during the past 60 years. The nutrient input, however, is not a key factor affecting the primary productivity in the three reservoirs. The above evidence demonstrates that some of the resistant monosaccharides have been significantly elevated by climate change, even in low-latitude regions.

  5. A time-series study of particulate matter export in the North Pacific Subtropical Gyre based on 234Th : 238U disequilibrium

    Science.gov (United States)

    Benitez-Nelson, Claudia; Buesseler, Ken O.; Karl, David M.; Andrews, John

    2001-12-01

    Depth profiles of total 234Th (dissolved+particulate) were collected at Station ALOHA (22°45N, 158°00W) in the North Pacific Subtropical Gyre during 9 cruises from April 1999 to March 2000. Samples were collected and processed by a new 2 L technique that enables more detailed depth resolution then previous 234Th studies. Significant zones of particle export ( 234Th deficiency) and particle remineralization ( 234Th excess) were measured both temporally and with depth. 234Th derived particulate carbon (PC) and nitrogen (PN) fluxes were determined with steady-state and non-steady-state models and PC/ 234Th and PN/ 234Th ratios measured with both in situ pumps and free-drifting particle interceptor traps deployed at 150 m. 234Th based export estimates of 4.0±2.3 mmol C m -2 d -1 and 0.53±0.19 mmol N m -2 d -1, were approximately 60% higher than those measured in PIT style sediment traps from the same time period, 2.4±0.2 mmol C m -2 d -1 and 0.32±0.08 mmol N m -2 d -1. Most of this difference is attributable to two large export events that occurred during October and December 1999, when traps undercollected for 234Th by a factor of 2 to 4. 234Th export ( ThE) ratios based on 234Th derived PC flux/ 14C based primary production ranged from 4% to 22% (average=8.8%). Our results confirm the recent estimates of C export by Emerson et al. (Nature 389 (1997) 951) and Sonnerup et al. (Deep-Sea Research I 46 (1999) 777) and indicate that C export from the oligotrophic ocean must be considered when discussing C sequestration in global climate change.

  6. Reconstructing Export Production in the Subantarctic South Pacific during the Last Ice Age

    Science.gov (United States)

    Park, J. W.; Winckler, G.; Anderson, R. F.; Schwartz, R.; Lamy, F.; Gersonde, R.; Pahnke, K.

    2016-02-01

    Despite high concentration of major nutrients in the Southern Ocean, nutrient utilization is inefficient because the scarcity of iron limits phytoplankton growth and primary productivity. Input of eolian dust into the ocean may supply iron, leading to increased export production and nutrient utilization, and potentially affect the Earth's carbon cycle through its fertilizing effect on marine ecosystem. Recent studies (Martínez-Garcia et al., 2009, 2011, 2014) suggest that iron fertilization in the Subantarctic South Atlantic may have contributed to reducing atmospheric CO2 by 40ppm over the last glacial cycle. While most of current observations on the Southern Ocean come from the South Atlantic, the Pacific sector covers the largest surface area of the Southern Ocean, indicating its potential to store the largest fraction of carbon. Dust fluxes to the South Atlantic are generally stronger than those to the South Pacific, but the glacial-interglacial pattern of dust deposition is similar. A recent study (Lamy et al., 2014) suggests a threefold increase of dust deposition over glacial periods than over interglacial periods in the South Pacific, and show a correlation between dust records and preliminary export production. In this study, we examine a set of cores from the Subantarctic South Pacific at higher temporal resolution to observe variability of export production in response to changing dust flux. We present proxy records for paleoproductivity from excess Ba, biogenic opal and authigenic Uranium. The results will allow us to evaluate the importance of iron fertilization in the Subantarctic Pacific Ocean over glacial/interglacial timescale and its potential effect on the global carbon cycle.

  7. Towards stock assessment of Jack Mackerel in the South Pacific, based on data from commercial vessels

    NARCIS (Netherlands)

    Ybema, M.S.; Brunel, T.P.A.; Machiels, M.A.M.; Quirijns, F.J.; Dickey-Collas, M.

    2008-01-01

    A recently developed international fishery for Jack Mackerel (Trachurus murphyi) in the South Pacific has instigated a need for Dutch participation in research into this fish and fishery. A three,year study was therefore commissioned by the Dutch Ministry of Agriculture, Nature and Food Quality and

  8. Proceedings of the 3rd workshop of the South Pacific Environmental Radioactivity Association (SPERA). Extended abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    The 1994 workshop of the South Pacific Environmental Radioactivity Association (SPERA) was held in Canberra, at the Australian National University. Presentations were grouped around the themes of geochronology, environmental impact and analytical techniques. This volume contains 26 extended abstracts and 3 poster-presentations which have been separately indexed for inclusion in the INIS database. A list of participants is also included.

  9. Relationships between the surface concentration of particulate organic carbon and optical properties in the eastern South Pacific and eastern Atlantic Oceans

    Directory of Open Access Journals (Sweden)

    D. Stramski

    2008-02-01

    Full Text Available We have examined several approaches for estimating the surface concentration of particulate organic carbon, POC, from optical measurements of spectral remote-sensing reflectance, Rrs(λ, using field data collected in tropical and subtropical waters of the eastern South Pacific and eastern Atlantic Oceans. These approaches include a direct empirical relationship between POC and the blue-to-green band ratio of reflectance, RrsB/Rrs(555, and two-step algorithms that consist of relationships linking reflectance to an inherent optical property IOP (beam attenuation or backscattering coefficient and POC to the IOP. We considered two-step empirical algorithms that exclusively include pairs of empirical relationships and two-step hybrid algorithms that consist of semianalytical models and empirical relationships. The surface POC in our data set ranges from about 10 mg m−3 within the South Pacific Subtropical Gyre to 270 mg m−3 in the Chilean upwelling area, and ancillary data suggest a considerable variation in the characteristics of particulate assemblages in the investigated waters. The POC algorithm based on the direct relationship between POC and RrsB/Rrs(555 promises reasonably good performance in the vast areas of the open ocean covering different provinces from hyperoligotrophic and oligotrophic waters within subtropical gyres to eutrophic coastal upwelling regimes characteristic of eastern ocean boundaries. The best error statistics were found for power function fits to the data of POC vs. Rrs(443/Rrs(555 and POC vs. Rrs(490/Rrs(555. For our data set that includes over 50 data pairs, these relationships are characterized by the mean normalized bias of about 2% and the normalized root mean square error of about 20%. We

  10. The application of lichens as ecological surrogates of air pollution in the subtropics: a case study in South Brazil.

    Science.gov (United States)

    Koch, Natália M; Branquinho, Cristina; Matos, Paula; Pinho, Pedro; Lucheta, Fabiane; Martins, Suzana M A; Vargas, Vera M F

    2016-10-01

    The use of lichens as ecological surrogates has been an important tool to evaluate the impact of air pollution in both ecosystem and human health but remains underused in the subtropics due to lack of knowledge. Aiming to support the application of lichen as ecological surrogates of the effects of air pollution in the subtropics, we hypothesized that urbanization was an important driver of changes on lichen diversity, composition, and vitality. For that, we quantified several lichen diversity metrics (richness, cover, and community composition) and photobiont vitality in relation to atmospheric pollution or its surrogates (modeled pollutant gases, pollutants in lichen thallus, and land cover). We confirmed that air pollution was a key driver for lichen diversity. Changes in lichen community composition and vitality were very significantly related to air pollution and integrated the effect of multiple stressors (particulate matter, NOx, and Cu), thus being powerful ecological indicators of air pollution in the subtropics.

  11. Increasing surface albedo in the dry subtropical forests of South America: the role of agriculture expansion and management

    Science.gov (United States)

    Houspanossian, J.; Kuppel, S.; Gimenez, R.; Jobbagy, E. G.; Nosetto, M. D.

    2014-12-01

    The increase in surface albedo inherent to land clearing and cultivation (land-cover change, LCC) in the subtropical dry forests of the South American Chaco offsets part of the radiative forcing (RF) of the related carbon emissions. The magnitude of these albedo changes, however, is also dependent on shifts in agricultural practices (land-management change, LMC) and will influence the net effect on Earth's radiation balance as well as other potential feedbacks on climate. We quantified the surface albedo changes between 2001 and 2013 and the consequent shifts in the radiation balance resulting from LCC and LMC, using MODIS imagery a columnar radiation model parameterized with satellite data. Agricultural systems replacing dry forests presented a large variety of managements, ranging from pasture systems with remnant trees to different grain crops, displaying a wide range of phenologies. Cultivated lands showed higher and more variable albedo values (mean = 0.162, Standard Deviation = 0.013, n = 10,000 pixels) than the dry forests they replace (mean = 0.113, SD = 0.010, n = 10,000). These albedo contrasts resulted in a cooling RF of deforestation of -10.1 W m-2 on average, but both livestock and grain crop production systems showed large differences among the different land management options. For instance, livestock systems based on open pasture lands showed higher albedo change and RF (0.06 and -16.3 W m-2, respectively) than silvopastoral systems (0.02 and -4.4 W m-2). Similarly in cropping systems, the replacement of double-cropping by single summer crops, a widespread process in the region lately, resulted in higher albedo change (0.06 vs. 0.08) and RF (-16.3 vs. -22.3 W m-2). Although the effects of LCC on climate are widely acknowledged, those of LMC are still scarcely understood. In the Chaco region, the latter could play an important role and offer a yet-overlooked pathway to influence the radiative balance of our planet.

  12. Location of South Georgia and potential impact on early Pacific-Atlantic through flow

    Science.gov (United States)

    Carter, A.; Curtis, M.

    2013-12-01

    One of the most significant Cenozoic reconfigurations of global ocean circulation involved the initiation of Pacific to Atlantic exchange that led to the isolation of Antarctica by the Antarctica Circumpolar Current though the separation of South America and Antarctica and the opening of the Scotia Sea and Drake Passage. Whether significant Pacific to Atlantic through-flow was possible in the early Cenozoic has remained unclear because it is not certain where continental fragments such as South Georgia, a potential barrier, were located before seafloor spreading created the Scotia Sea. Establishing where South Georgia was located is also critical to reconstructing the Scotia arc and understanding its evolution. Detrital zircon U-Pb geochronology and apatite thermochronometry are used to constrain the pre-drift location of South Georgia. Data from Cretaceous turbidites exposed on South Georgia are consistent with a former connection to the Rocas Verdes back-arc basin giving support to models that have argued for a pre- tectonic translation location southeast of Tierra del Fuego. Following an early phase of rock uplift, thermal history models of the apatite chronometry data indicate that the South Georgia continental fragment underwent burial related heating and was therefore not a significant topographic feature until it emerged c. 10-7 Ma coeval with the cessation of spreading at the West Scotia Ridge and collision between the South Georgia continental block and the Northeast Georgia Rise.

  13. On the origin of tropospheric ozone and NOx over the tropical South Pacific

    OpenAIRE

    Schultz, Martin G.; Jacob, Daniel James; Wang, Yuhang; Logan, Jennifer A.; Atlas, Elliot L.; Blake, Donald R.; Blake, Nicola J.; Bradshaw, John D.; Browell, Edward V.; Fenn, Marta A.; Flocke, Frank; Gregory, Gerald L; Heikes, Brian G.; Sachse, Glen W.; Sandholm, Scott T.

    1999-01-01

    The budgets of ozone and nitrogen oxides (NOx = NO + NO2) in the tropical South Pacific troposphere are analyzed by photochemical point modeling of aircraft observations at 0–12 km altitude from the Pacific Exploratory Mission-Tropics A campaign flown in September-October 1996. The model reproduces the observed NO2/NO concentration ratio to within 30% and has similar success in simulating observed concentrations of peroxides ( H2O2, CH3OOH), lending confidence in its use to investigate ozone ...

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

    Directory of Open Access Journals (Sweden)

    Patricia Miloslavich

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

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

    Science.gov (United States)

    Miloslavich, Patricia; Klein, Eduardo; Díaz, Juan M; Hernández, Cristián E; Bigatti, Gregorio; Campos, Lucia; Artigas, Felipe; Castillo, Julio; Penchaszadeh, Pablo E; Neill, Paula E; Carranza, Alvar; Retana, María V; Díaz de Astarloa, Juan M; Lewis, Mirtha; Yorio, Pablo; Piriz, María L; Rodríguez, Diego; Yoneshigue-Valentin, Yocie; Gamboa, Luiz; Martín, Alberto

    2011-01-31

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

  16. A coupled stable isotope-size spectrum approach to understanding pelagic food-web dynamics: A case study from the southwest sub-tropical Pacific

    Science.gov (United States)

    Hunt, B. P. V.; Allain, V.; Menkes, C.; Lorrain, A.; Graham, B.; Rodier, M.; Pagano, M.; Carlotti, F.

    2015-03-01

    This study investigated the food web structure of the oligotrophic picophytoplankton-dominated pelagic ecosystem in the vicinity of New Caledonia, within the Archipelagic Deep Basin (ARCH) province of the southwest sub-tropical Pacific. Nitrogen stable isotope (δ15N) data were collected for mesozooplankton (0.2-2 mm), macrozooplankton (2-20 mm), micronekton (20-200 mm) and nekton (>200 mm) during 2002-2004 and 2011. Using a coupled δ15N size-spectrum approach, we estimated (1) organism trophic level (TL); (2) food chain length (FCL); (3) predator prey mass ratio (PPMR); and (4) transfer efficiency (TE). The role of phytoplankton size structure in determining these parameters was investigated. Applying a trophic enrichment factor (TEF) of 3.4, maximum TL was calculated at ~5. The number of TLs spanned by each length class was 1.97 for mesozooplankton, 2.07 for macrozooplankton, 2.75 for micronekton, and 2.21 for nekton. Estimated PPMR was 10,099:1 for mesozooplankton, 3683:1 for macrozooplankton/micronekton, and 2.44×105:1 for nekton, corresponding to TEs of 6.3%, 8.5% and 2.4%, respectively. PPMR and TE were strongly influenced by the TEF used, and TEF 3.4 likely over and underestimated PPMR and TE, respectively, for mesozooplankton and macrozooplankton/micronekton. Comparatively low PPMR for mesozooplankton and macrozooplankton/micronekton indicated longer food chains and higher connectivity within these groups than for the nekton. Conversely, the high PPMR yet high trophic niche width for the nekton indicated that they prey primarily on macrozooplankton/micronekton, with a relatively high degree of dietary specialisation. Our results are discussed in the context of other marine food webs. The ARCH food chain was found to be 1-1.5 trophic levels longer than the eutrophic micro-/nanophytoplankton-dominated Californian upwelling system, providing empirical support for the role of phytoplankton size in determining FCL. Group specific PPMR estimates demonstrated

  17. Sources and transformation of dissolved and particulate organic nitrogen in the North Pacific Subtropical Gyre indicated by compound-specific δ15N analysis of amino acids

    Science.gov (United States)

    Yamaguchi, Yasuhiko T.; McCarthy, Matthew D.

    2018-01-01

    This study explores the use of compound-specific nitrogen isotopes of amino acids (δ15NAA) of coupled dissolved and particulate organic nitrogen (DON, PON) samples as a new approach to examine relative sources, transformation processes, and the potential coupling of these two major forms of N cycle in the ocean water column. We measured δ15NAA distributions in high-molecular-weight dissolved organic nitrogen (HMW DON) and suspended PON in the North Pacific Subtropical Gyre (NPSG) from surface to mesopelagic depths. A new analytical approach achieved far greater δ15NAA measurement precision for DON than earlier work, allowing us to resolve previously obscured differences in δ15NAA signatures, both with depth and between ON pools. We propose that δ15N values of total hydrolysable amino acids (THAA) represents a proxy for proteinaceous ON δ15N values in DON and PON. Together with bulk δ15N values, this allows δ15N values and changes in bulk, proteinaceous, and ;other-N; to be directly evaluated. These novel measurements suggest three main conclusions. First, the δ15NAA signatures of both surface and mesopelagic HMW DON suggest mainly heterotrophic bacterial sources, with mesopelagic HMW DON bearing signatures of far more degraded material compared to surface material. These results contrast with a previous proposal that HMW DON δ15NAA patterns are essentially ;pre-formed; by cyanobacteria in the surface ocean, undergo little change with depth. Second, different δ15NAA values and patterns of HMW DON vs. suspended PON in the surface NPSG suggest that sources and cycling of these two N reservoirs are surpisingly decoupled. Based on molecular δ15N signatures, we propose a new hypothesis that production of surface HMW DON is ultimately derived from subsurface nitrate, while PON in the mixed layer is strongly linked to N2 fixation and N recycling. In contrast, the comparative δ15NAA signatures of HMW DON vs. suspended PON in the mesopelagic also suggest a

  18. Effect of urbanization on the structure and functional traits of remnant subtropical evergreen broad-leaved forests in South China

    Science.gov (United States)

    Liujing Huang; Hongfeng Chen; Hai Ren; Jun Wang; Qinfeng Guo

    2013-01-01

    We investigated the effects of major environmental drivers associated with urbanization on species diversity and plant functional traits (PFTs) in the remnant subtropical evergreen broad-leaved forests in Metropolitan Guangzhou (Guangdong, China). Twenty environmental factors including topography, light, and soil properties were used to quantify the effects of...

  19. Zooplankton, temperature, salinity, and nutrients data from bottle and net casts in the South Pacific and Equatorial Pacific Oceans from the CORIOLIS from 05 April 1981 to 16 August 1981 (NODC Accession 0000527)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Zooplankton, nutrients, and other data were collected from bottle and net casts in the South Pacific and Equatorial Pacific Oceans from the CORIOLIS from 05 April...

  20. Physical and underway data collected aboard the MELVILLE during cruise MV1007 in the North Pacific Ocean and South Pacific Ocean from 2010-05-17 to 2010-06-16 (NODC Accession 0089615)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089615 includes physical and underway data collected aboard the MELVILLE during cruise MV1007 in the North Pacific Ocean and South Pacific Ocean from...

  1. Physical and underway data collected aboard the ATLANTIS during cruise AT15-63 in the North Pacific Ocean and South Pacific Ocean from 2010-03-15 to 2010-04-14 (NODC Accession 0103918)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0103918 includes physical and underway data collected aboard the ATLANTIS during cruise AT15-63 in the North Pacific Ocean and South Pacific Ocean...

  2. Chemical, optical and other data collected aboard the MELVILLE during cruise MV1105 in the North Pacific Ocean and South Pacific Ocean from 2011-04-29 to 2011-05-28 (NODC Accession 0116958)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0116958 includes chemical, optical and other data collected aboard the MELVILLE during cruise MV1105 in the North Pacific Ocean and South Pacific...

  3. Physical and underway data collected aboard the KNORR during cruise KN195-03 in the North Pacific Ocean and South Pacific Ocean from 2009-01-12 to 2009-02-23 (NODC Accession 0104265)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0104265 includes physical and underway data collected aboard the KNORR during cruise KN195-03 in the North Pacific Ocean and South Pacific Ocean from...

  4. Physical and underway data collected aboard the ATLANTIS during cruise AT15-43 in the North Pacific Ocean and South Pacific Ocean from 2009-01-09 to 2009-02-16 (NODC Accession 0103873)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0103873 includes physical and underway data collected aboard the ATLANTIS during cruise AT15-43 in the North Pacific Ocean and South Pacific Ocean...

  5. [Effects of elevated CO2 concentration and nitrogen deposition on the biomass accumulation and allocation in south subtropical main native tree species and their mixed communities].

    Science.gov (United States)

    Zhao, Liang; Zhou, Guo-yi; Zhang, De-qiang; Duan, Hong-lang; Liu, Ju-xiu

    2011-08-01

    A 5-year experiment was conducted to study the effects of simulated elevated CO2 concentration, nitrogen deposition, and their combination on the biomass accumulation and allocation in five south subtropical native tree species Schima superba, Ormosia pinnata, Acmena acuminatissima, Syzygium hancei, and Castanopsis hystrix and their mixed communities. The test tree species had different responses in their biomass accumulation and allocation to the elevated CO2 concentration and nitrogen deposition. Elevated CO2 concentration and nitrogen deposition increased the biomass of legume species by 49.3% and 71.0%, respectively, and promoted the biomass accumulation in sun species. Nitrogen deposition increased the biomass of shade-preference species significantly, but elevated CO2 concentration was in adverse. Elevated CO2 concentration inhibited the biomass allocation in the belowground part of sun species but promoted the biomass allocation in the belowground part of shade-preference species. Elevated CO2 concentration, nitrogen deposition, and their interaction all promoted the biomass accumulation in mixed communities. Elevated CO2 concentration increased the biomass accumulation in the belowground part of the communities, while nitrogen deposition increased the biomass accumulation in the aboveground part. Under the background of global climate change, Ormosia pinnata and Castanopsis hystrix tended to be the appropriate species for carbon fixation in south subtropical area.

  6. Borders in the South: Migration News in South Asia and the Pacific

    Directory of Open Access Journals (Sweden)

    Jahnnabi Das

    2016-07-01

    Full Text Available In the age of unprecedented movement of people, many migrants end up in the industrialized countries but originate from all over the world. A fuller picture of migration journalism thus warrants examining news from both the ‘source’ and ‘receiving’ countries of migration. However, most of the studies undertaken in this particular area deal with the issues from the perspectives of North America and Europe (i.e., ‘receiving’ countries, an approach which is inconsistent with the broad goal of comparative studies. The current study examines migration news from both the source and receiving countries. Given that South Asia and the Pacific are two regions that tend to be overlooked in the comparative studies literature, we studied the coverage of migration issues in six prominent English-language newspapers from six countries of these regions (Australia, Bangladesh, India, New Zealand, Pakistan and Sri Lanka over a four-month period in 2014. Our study utilized an exploratory frame analysis to determine whether, in line with several earlier studies, issues of migration are depicted as a crisis to be managed in the receiving countries. Moreover, we examined the emphasis attached to the subject matter by the source countries’ media. The findings suggest that the media frames in receiving countries are more diverse than expected. While newspapers in some countries follow the previously found crisis frame, others highlight the economic benefits of migration. Similarly, in the source countries, the frames are varied. Most newspapers portray migration as a problem to be solved, but some do focus on protecting the interests of the migrants.

  7. Diversity of culturable filamentous Ascomycetes in the eastern South Pacific Ocean off Chile.

    Science.gov (United States)

    Vera, Jeanett; Gutiérrez, Marcelo H; Palfner, Götz; Pantoja, Silvio

    2017-08-01

    Our study reports the diversity of culturable mycoplankton in the eastern South Pacific Ocean off Chile to contribute with novel knowledge on taxonomy of filamentous fungi isolated from distinct physicochemical and biological marine environments. We characterized spatial distribution of isolates, evaluated their viability and assessed the influence of organic substrate availability on fungal development. Thirty-nine Operational Taxonomic Units were identified from 99 fungal strains isolated from coastal and oceanic waters by using Automatic Barcode Gap Discovery. All Operational Taxonomic Units belonged to phylum Ascomycota and orders Eurotiales, Dothideales, Sordariales and Hypocreales, mainly Penicillium sp. (82%); 11 sequences did not match existing species in GenBank, suggesting occurrence of novel fungal taxa. Our results suggest that fungal communities in the South Pacific Ocean off Chile appear to thrive in a wide range of environmental conditions in the ocean and that substrate availability may be a factor influencing fungal viability in the ocean.

  8. Petroleum geology of Pacific margin of Central America and northern South America, from Guatemala to Ecuador

    Energy Technology Data Exchange (ETDEWEB)

    Scrutton, M.E.; Escalante, G.F.

    1986-07-01

    Exploration for hydrocarbons along the Pacific margin of Central America and northern South America has been limited and spasmodic. Less than 100 exploration wells have been drilled, with nearly 50 of these being in the Santa Elena, Progreso, and Guayas basins in Ecuador. Shows have been reported in some wells, and a few oil seeps are known. The only commercial production established to date has been from the Santa Elena Peninsula in Ecuador in the extreme south of the study area. Understanding of the geology in this part of the continental margin is incomplete at best. This paper reviews present-day knowledge in an attempt to define the sedimentary basins better, to characterize their structure and stratigraphy, and to assess their petroleum prospects. The area of continental margin reviewed is to the north, located northwest of the trench system where oceanic crust of the Cocos plate subducts under the Caribbean plate, and to the south, where the northern part of the Nazca plate collides with the South American plate. This plate tectonic setting forms the framework on which local structural and sedimentary events have created a series of relatively small trench-slope and forearc basins in what is now the coastal plain and adjacent offshore area of Central and South America, south or west of a line of mountain ranges with active volcanism. Sedimentary fill is generally of Tertiary age. The basins and subbasins recognized and described include: in Ecuador - Guayas, Santa Elena, Progreso, Valdivia, Bajo Grande, Manta, Muisne-Esmeraldas, and Borbon; in Colombia - Choco-Pacific; in Panama - Gulf of Panama basin complex (Santiago, Tonosi, Sambu), and Burica-Chiriqui; in Costa Rica - Terraba and Coronado/Tempisque; in Nicaragua - San Juan del Sur; and in the Honduras, El Salvador, and Guatemala - the Pacific coastal basin.

  9. Input and output of dissolved organic and inorganic nitrogen in subtropical forests of South China under high air pollution

    Directory of Open Access Journals (Sweden)

    Y. T. Fang

    2008-03-01

    Full Text Available The nitrogen (N emissions to the atmosphere and N deposition to forest ecosystems are increasing rapidly in Southeast Asia, but little is known about the fates and effects of elevated N deposition in forest ecosystems in this warm and humid region. Here we report the concentrations and fluxes of dissolved inorganic (DIN and organic N (DON in precipitation, throughfall, surface runoff and soil solution for three subtropical forests in a region of South China under high air pollution over two years (2004 and 2005, to investigate how deposited N is processed, and to examine the importance of DON in the N budget. The precipitation DIN input was 32–34 kg N ha−1 yr−1. An additional input of 18 kg N ha−1 yr−1 as DON was measured in 2005, which to our knowledge is the highest DON flux ever measured in precipitation. A canopy uptake of DIN was indicated in two young conifer dominated forests (72–85% of DIN input reached the floor in throughfall, whereas no uptake occurred in an old-growth broadleaf forest. The DON fluxes in throughfall were similar to that in precipitation in all forests. In the younger forests, DIN was further retained in the soil, with 41–63% of precipitation DIN leached below the 20-cm soil depth. Additionally, about half of the DON input was retained in these forests. The N retention in two young aggrading forests (21–28 kg N ha−1 yr−1 was in accordance with the estimates of N accumulation in biomass and litter accretion. In the old-growth forest, no N retention occurred, but rather a net loss of 8–16 kg N ha−1 yr−1 from the soil was estimated. In total up to 60 kg N ha−1 yr−1 was leached from the old-growth forest, indicating that this forest was completely N saturated and could not retain additional anthropogenic N inputs. We found that the majority of DIN deposition as well as of DIN leaching

  10. New bioactive halenaquinone derivatives from South Pacific marine sponges of the genus Xestospongia

    OpenAIRE

    Longeon, A.; Copp, B. R.; Roué, M.; Dubois, J.; Valentin, A.; Petek, Sylvain; Debitus, Cécile; Bourguet-Kondracki, M.L.

    2010-01-01

    Bioassay-directed fractionation of South Pacific marine sponges of the genus Xestospongia has led to the isolation of a number of halenaquinone-type polyketides, including two new derivatives named xestosaprol C methylacetal 7 and orhalquinone 8. Chemical characterization of these two new compounds was achieved by extensive 1D and 2D NMR spectroscopic studies. Evaluation of anti-phospholipase A(2), anti-farnesyltransferase and antiplasmodial activities of this series is presented and structur...

  11. The Pacific Marine Energy Center - South Energy Test Site (PMEC-SETS)

    Energy Technology Data Exchange (ETDEWEB)

    Hellin, Dan; Batten, Belinda

    2018-02-07

    The overall goal of this project was to build on existing progress to establish the Pacific Marine Energy Center South Energy Test Site (PMEC-SETS) as the nation's first fully permitted test site for wave energy converter arrays. Specifically, it plays an essential role in reducing levelized cost of energy for the wave energy industry by providing both the facility and resources to addres the challenges of cost reduction.

  12. Short-lived and discontinuous intraplate volcanism in the South Pacific: Hot spots or extensional volcanism?

    Science.gov (United States)

    Koppers, Anthony A. P.; Staudigel, Hubert; Pringle, Malcolm S.; Wijbrans, Jan R.

    2003-10-01

    South Pacific intraplate volcanoes have been active since the Early Cretaceous. Their HIMU-EMI-EMII mantle sources can be traced back into the West Pacific Seamount Province (WPSP) using plate tectonic reconstructions, implying that these distinctive components are enduring features within the Earth's mantle for, at least, the last 120 Myr. These correlations are eminent on the scale of the WPSP and the South Pacific Thermal and Isotopic Anomaly (SOPITA), but the evolution of single hot spots emerges notably more complicated. Hot spots in the WPSP and SOPITA mantle regions typically display intermittent volcanic activity, longevities shorter than 40 Myr, superposition of hot spot volcanism, and motion relative to other hot spots. In this review, we use 40Ar/39Ar seamount ages and Sr-Nd-Pb isotopic signatures to map out Cretaceous volcanism in the WPSP and to characterize its evolution with respect to the currently active hot spots in the SOPITA region. Our plate tectonic reconstructions indicate cessation of volcanism during the Cretaceous for the Typhoon and Japanese hot spots; whereas the currently active Samoan, Society, Pitcairn and Marquesas hot spots lack long-lived counterparts in the WPSP. These hot spots may have become active during the last 20 Myr only. The other WPSP seamount trails can be only "indirectly" reconciled with hot spots in the SOPITA region. Complex age distributions in the Magellan, Anewetak, Ralik and Ratak seamount trails would necessitate the superposition of multiple volcanic trails generated by the Macdonald, Rurutu and Rarotonga hot spots during the Cretaceous; whereas HIMU-type seamounts in the Southern Wake seamount trail would require 350-500 km of hot spot motion over the last 100 Myr following its origination along the Mangaia-Rurutu "hotline" in the Cook-Austral Islands. These observations, however, violate all assumptions of the classical Wilson-Morgan hot spot hypothesis, indicating that long-lived, deep and fixed mantle

  13. Profile chemical and physical data collected aboard the KILO MOANA in the South Pacific Ocean and the Coral Sea from March 15, 2007 to April 14, 2007 (NODC Accession 0059113)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains hydrographic data collected during cruise KM0703 in the tropical and subtropical Southwest Pacific. Leg 1 of the cruise began in Townsville,...

  14. Spice: Southwest Pacific Ocean Circulation and Climate Experiment

    Science.gov (United States)

    Ganachaud, A. S.; Melet, A.; Maes, C.

    2010-12-01

    South Pacific oceanic waters are carried from the subtropical gyre centre in the westward flowing South Equatorial Current (SEC), towards the southwest Pacific-a major circulation pathway that redistributes water from the subtropics to the equator and Southern Ocean. The transit in the Coral Sea is potentially of great importance to tropical climate prediction because changes in either the temperature or the amount of water arriving at the equator have the capability to modulate ENSO and produce basin-scale climate feedbacks. The south branch is associated with comparable impacts in the Tasman Sea area. The Southwest Pacific is a region of complex circulation, with the SEC splitting in strong zonal jets upon encountering island archipelagos. Those jets partition on the Australian eastern boundary to feed the East Australian Current for the southern branch and the North Queensland Current and eventually the Equatorial Undercurrent for the northern branch. On average, the oceanic circulation is driven by the Trade Winds, and subject to substantial variability, related with the South Pacific Convergence Zone (SPCZ) position and intensity. The circulation, and its influence on remote and regional climate, is poorly understood due to the lack of appropriate measurements. Ocean and atmosphere scientists from Australia, France, New Zealand, the United States and Pacific Island countries initiated an international research project under the auspices of CLIVAR to comprehend the southwest Pacific Ocean circulation and its direct and indirect influence on the climate and environment. SPICE is a regionally-coordinated experiment to measure, study and monitor the ocean circulation and the SPCZ, to validate and improve numerical models, and to integrate with assimilating systems. This ongoing project reflects a strong sense that substantial progress can be made through collaboration among South Pacific national research groups, coordinated with broader South Pacific projects.

  15. ENSO related SST anomalies and relation with surface heat fluxes over south Pacific and Atlantic

    Science.gov (United States)

    Chatterjee, S.; Nuncio, M.; Satheesan, K.

    2017-07-01

    The role of surface heat fluxes in Southern Pacific and Atlantic Ocean SST anomalies associated with El Nino Southern Oscillation (ENSO) is studied using observation and ocean reanalysis products. A prominent dipole structure in SST anomaly is found with a positive (negative) anomaly center over south Pacific (65S-45S, 120W-70W) and negative (positive) one over south Atlantic (50S-30S, 30W-0E) during austral summer (DJF) of El Nino (LaNina). During late austral spring-early summer (OND) of El Nino (LaNina), anomalous northerly (southerly) meridional moisture transport and a positive (negative) sea level pressure anomaly induces a suppressed (enhanced) latent heat flux from the ocean surface over south Pacific. This in turn results in a shallower than normal mixed layer depth which further helps in development of the SST anomaly. Mixed layer thins further due to anomalous shortwave radiation during summer and a well developed SST anomaly evolves. The south Atlantic pole exhibits exactly opposite characteristics at the same time. The contribution from the surface heat fluxes to mixed layer temperature change is found to be dominant over the advective processes over both the basins. Net surface heat fluxes anomaly is also found to be maximum during late austral spring-early summer period, with latent heat flux having a major contribution to it. The anomalous latent heat fluxes between atmosphere and ocean surface play important role in the growth of observed summertime SST anomaly. Sea-surface height also shows similar out-of-phase signatures over the two basins and are well correlated with the ENSO related SST anomalies. It is also observed that the magnitude of ENSO related anomalies over the southern ocean are weaker in LaNina years than in El Nino years, suggesting an intensified tropics-high latitude tele-connection during warm phases of ENSO.

  16. Secondary Hotspots in the South Pacific as a Result of Mantle Plumelets and Lithospheric Extension?

    Science.gov (United States)

    Koppers, A.; Staudigel, H.; Wijbrans, J.; Pringle, M.

    2003-12-01

    By far the largest number of secondary hotspots (cf. Courtillet et al., 2003) can be found in the "South Pacific Thermal and Isotopic Anomaly" (SOPITA) or "Superswell" region. Its Cretaceous counterpart is preserved in a large range of seamounts and guyots found in the "West Pacific Seamount Province" (WPSP). The seamounts in these regions display very distinct and long-lived isotopic signatures (Staudigel et al., 1991; Koppers et al., 2003) that can be used to combine source region chemistry and seamount geochronology to map out mantle melting anomalies over geological time. These mappings may resolve many important questions regarding the stationary character, continuity and longevity of the melting anomalies in the South Pacific mantle - and its secondary hotspots. Of all secondary hotspots that are currently active in the SOPITA we could identify only two hotspots that appear to be long-lived and that have Cretaceous counterparts in the WPSP. Plate reconstructions show that the "HIMU-type" Southern Wake seamounts may have originated from the Mangaia-Rurutu "hotline" in the Cook-Austral Islands, whereas the "EMI-type" Magellan seamounts may have originated from the Rarotonga hotspot. All other hotspots in the SOPITA and WPSP are short-lived (or intermittently active) as evidenced by the presence of numerous seamount trail "segments" representing no more than 10-40 Myr of volcanism. Our observations violate one or more assumptions of the classical Wilson-Morgan hotspot hypothesis: (1) none of the South Pacific hotspots are continuously active, (2) most are short-lived, (3) some show evidence of hotspot motion, and (4) most of them have poor linear age progressions, if any at all. On top of this we have evidence for volcanism along "hotlines" and the "superposition" of hotspots. The simple and elegant "hotspot" model, therefore, seems insufficient to explain the age distribution and source region characteristics of intra-plate volcanoes in the South Pacific. This

  17. A synthesis of the environmental response of the North and South Atlantic Sub-Tropical Gyres during two decades of AMT

    Science.gov (United States)

    Aiken, Jim; Brewin, Robert J. W.; Dufois, Francois; Polimene, Luca; Hardman-Mountford, Nick J.; Jackson, Thomas; Loveday, Ben; Hoya, Silvana Mallor; Dall'Olmo, Giorgio; Stephens, John; Hirata, Takafumi

    2017-11-01

    Anthropogenically-induced global warming is expected to decrease primary productivity in the subtropical oceans by strengthening stratification of the water column and reducing the flux of nutrients from deep-waters to the sunlit surface layers. Identification of such changes is hindered by a paucity of long-term, spatially-resolved, biological time-series data at the basin scale. This paper exploits Atlantic Meridional Transect (AMT) data on physical and biogeochemical properties (1995-2014) in synergy with a wide range of remote-sensing (RS) observations from ocean colour, Sea Surface Temperature (SST), Sea Surface Salinity (SSS) and altimetry (surface currents), combined with different modelling approaches (both empirical and a coupled 1-D Ecosystem model), to produce a synthesis of the seasonal functioning of the North and South Atlantic Sub-Tropical Gyres (STGs), and assess their response to longer-term changes in climate. We explore definitive characteristics of the STGs using data of physical (SST, SSS and peripheral current systems) and biogeochemical variables (chlorophyll and nitrate), with inherent criteria (permanent thermal stratification and oligotrophy), and define the gyre boundary from a sharp gradient in these physical and biogeochemical properties. From RS data, the seasonal cycles for the period 1998-2012 show significant relationships between physical properties (SST and PAR) and gyre area. In contrast to expectations, the surface layer chlorophyll concentration from RS data (CHL) shows an upward trend for the mean values in both subtropical gyres. Furthermore, trends in physical properties (SST, PAR, gyre area) differ between the North and South STGs, suggesting the processes responsible for an upward trend in CHL may vary between gyres. There are significant anomalies in CHL and SST that are associated with El Niño events. These conclusions are drawn cautiously considering the short length of the time-series (1998-2012), emphasising the need

  18. Inorganic and organic nitrogen acquisition by a fern Dicranopteris dichotoma in a subtropical forest in South China.

    Directory of Open Access Journals (Sweden)

    Xingliang Xu

    Full Text Available The fern Dicranopteris dichotoma is an important pioneer species of the understory in Masson pine (Pinus massoniana forests growing on acidic soils in the subtropical and tropical China. To improve our understanding of the role of D. dichotoma in nitrogen (N uptake of these forests, a short-term (15N experiment was conducted at mountain ridge (MR, with low N level and mountain foot (MF, with high N level. We injected (15N tracers as (15NH4, (15NO3 or (15N-glycine into the soil surrounding each plant at both MR and MF sites. Three hours after tracer injection, the fern D. dichotoma took up 15NH4+ significantly faster at MF than at MR, but it showed significantly slower uptake of (15NO3- at MF than at MR. Consequently, (15NO3- made greater contribution to the total N uptake (50% to the total N uptake at MR than at MF, but (15N-glycine only contributed around 11% at both sites. Twenty-four hours after tracer injection, D. dichotoma preferred (15NH4+ (63% at MR, whereas it preferred (15NO3- (47% at MF. We concluded that the D. dichotoma responds distinctly in its uptake pattern for three available N species over temporal and spatial scales, but mainly relies on inorganic N species in the subtropical forest. This suggests that the fern employs different strategies to acquire available N which depends on N levels and time.

  19. Revision of the genus Lolliguncula Steenstrup, 1881 (Cephalopoda: Loliginidae off the Pacific Coast of South America

    Directory of Open Access Journals (Sweden)

    Franz Cardoso

    2013-12-01

    Full Text Available In the present paper the species from the genus LolligunculaSteentrup, 1881 (Cephalopoda: Loliginidae in Southeastern Pacific Ocean are reviewed. The presence of Lolliguncula (Lolliguncula panamensisBerry, 1911, Lolliguncula (Loliolopsis diomedeae Hoyle, 1911 and Lolliguncula (Lolliguncula argusBrakoniecki and Roper, 1985 are confirmed from Mexican waters to Perú and the species Lolliguncula (Lolliguncula arguscollected during a cruise of the R/V Anton Bruunfrom 1966 off the coast of South America is recorded for the first time in Peruvian waters. A key to identification of Pacific species is given. We report a diagnostic feature with taxonomic remarks of these species. Updated information on the distribution, biology, and fisheries of each species also is discussed.

  20. Oxygen distribution and aerobic respiration in the north and south eastern tropical Pacific oxygen minimum zones

    DEFF Research Database (Denmark)

    Tiano, Laura; Garcia-Robledo, Emilio; Dalsgaard, Tage

    2014-01-01

    Highly sensitive STOX O-2 sensors were used for determination of in situ O-2 distribution in the eastern tropical north and south Pacific oxygen minimum zones (ETN/SP OMZs), as well as for laboratory determination of O-2 uptake rates of water masses at various depths within these OMZs. Oxygen...... was generally below the detection limit (few nmol L-1) in the core of both OMZs, suggesting the presence of vast volumes of functionally anoxic waters in the eastern Pacific Ocean. Oxygen was often not detectable in the deep secondary chlorophyll maximum found at some locations, but other secondary maxima...... contained up to similar to 0.4 mu mol L-1. Directly measured respiration rates were high in surface and subsurface oxic layers of the coastal waters, reaching values up to 85 nmol L-1 O-2 h(-1). Substantially lower values were found at the depths of the upper oxycline, where values varied from 2 to 33 nmol...

  1. Reduced admixture of North Atlantic Deep Water to the deep central South Pacific during the last two glacial periods

    Science.gov (United States)

    Molina-Kescher, Mario; Frank, Martin; Tapia, Raúl; Ronge, Thomas A.; Nürnberg, Dirk; Tiedemann, Ralf

    2016-06-01

    The South Pacific is a sensitive location for the variability of the global oceanic thermohaline circulation given that deep waters from the Atlantic Ocean, the Southern Ocean, and the Pacific Basin are exchanged. Here we reconstruct the deep water circulation of the central South Pacific for the last two glacial cycles (from 240,000 years ago to the Holocene) based on radiogenic neodymium (Nd) and lead (Pb) isotope records complemented by benthic stable carbon data obtained from two sediment cores located on the flanks of the East Pacific Rise. The records show small but consistent glacial/interglacial changes in all three isotopic systems with interglacial average values of -5.8 and 18.757 for ɛNd and 206Pb/204Pb, respectively, whereas glacial averages are -5.3 and 18.744. Comparison of this variability of Circumpolar Deep Water (CDW) to previously published records along the pathway of the global thermohaline circulation is consistent with reduced admixture of North Atlantic Deep Water to CDW during cold stages. The absolute values and amplitudes of the benthic δ13C variations are essentially indistinguishable from other records of the Southern Hemisphere and confirm that the low central South Pacific sedimentation rates did not result in a significant reduction of the amplitude of any of the measured proxies. In addition, the combined detrital Nd and strontium (87Sr/86Sr) isotope signatures imply that Australian and New Zealand dust has remained the principal contributor of lithogenic material to the central South Pacific.

  2. Mapping Economic Development: The South Seas Government and Sugar Production in Japan’s South Pacific Mandate, 1919–1941

    Directory of Open Access Journals (Sweden)

    Ti Ngo

    2012-03-01

    Full Text Available Japan acquired the Mariana, Caroline, and Marshall Island chains as a League of Nations mandate following World War I. Why did the local administration (the South Seas Government or Nanyōchō heavily subsidize the establishment of a sugar industry? While the South Seas Government did not explicitly state why it chose to support the sugar industry despite the wealth of oceanic resources surrounding the islands, imperial maps of the South Pacific produced by the Japanese navy and the South Seas Government provide a window into how both parties envisioned and planned for the economic future of the mandate. These maps included information regarding the available natural resources, land, and culture level of the Micronesian population. The author argues that in depicting the islands as spaces where a “primitive” nonagricultural population failed to take advantage of the islands’ resources, mapmakers and officials planned for the mass migration of Japanese labor to the mandate in order to support a newly established sugar industry.

  3. Dynamics of soil inorganic nitrogen and their responses to nitrogen additions in three subtropical forests, south China

    DEFF Research Database (Denmark)

    Fang, Yun-ting; Zhu, Wei-xing; Mo, Jiang-ming

    2006-01-01

    evergreen broadleaved forest that has been protected for more than 400 years exhibited an advanced soil N status than the pine (Pinus massoniana) and pine-broadleaf mixed forests, both originated from the 1930's clear-cut and pine plantation. Mature forests had greater extractable inorganic N pool, lower N......Three forests with different historical land-use, forest age, and species assemblages in subtropical China were selected to evaluate current soil N status and investigate the responses of soil inorganic N dynamics to monthly ammonium nitrate additions. Results showed that the mature monsoon...... retention capacity, higher inorganic N leaching, and higher soil C/N ratios. Mineral soil extractable NH4+-N and NO3--N concentrations were significantly increased by experimental N additions on several sampling dates, but repeated ANOVA showed that the effect was not significant over the whole year except...

  4. Tracing latitudinal gradient, river discharge and water masses along the subtropical South American coast using benthic Foraminifera assemblages

    Directory of Open Access Journals (Sweden)

    PPB Eichler

    Full Text Available More than 30% of Buccella peruviana (D'Orbigny, Globocassidulina crassa porrecta (Earland & Heron-Allen, Cibicides mackannai (Galloway & Wissler and C. refulgens (Montfort indicate the presence of cold Sub Antarctic Shelf Water in winter, from 33.5 to 38.3º S, deeper than 100 m, in the southern part of the study area. In summer, the abundance of this association decreases to less than 15% around 37.5-38.9º S where two species (Globocassidulina subglobosa (Brady, Uvigerina peregrina (Cushman take over. G. subglobosa, U. peregrina, and Hanzawaia boueana (D'Orbigny are found at 27-33º S in both seasons in less than 55 m deep in the northern part, and are linked with warm Subtropical Shelf Water and Tropical Water. Freshwater influence was signalized by high silicate concentration and by the presence of Pseudononion atlanticum (Cushman, Bolivina striatula (Cushman, Buliminella elegantissima (D'Orbigny, Bulimina elongata (D'Orbigny, Elphidium excavatum (Terquem, E. poeyanum (D'Orbigny, Ammobaculites exiguus (Cushman & Brönnimann, Arenoparrella mexicana (Kornfeld, Gaudryina exillis (Cushman & Brönnimann, Textularia earlandi (Parker and thecamoebians in four sectors of the shelf. The presence of Bulimina marginata (D'Orbigny between 34.1-32.8º S in the winter and 34.2-32.7º S in the summer indicates that the influence of the Subtropical Shelf Front on the sediment does not change seasonally, otherwise, the presence of Angulogerina angulosa (Williamson in the winter, only in Mar del Plata (38.9º S, show that Malvinas currents are not influencing the sediment in the summer.

  5. Effect of urbanization on the structure and functional traits of remnant subtropical evergreen broad-leaved forests in South China.

    Science.gov (United States)

    Huang, Liujing; Chen, Hongfeng; Ren, Hai; Wang, Jun; Guo, Qinfeng

    2013-06-01

    We investigated the effects of major environmental drivers associated with urbanization on species diversity and plant functional traits (PFTs) in the remnant subtropical evergreen broad-leaved forests in Metropolitan Guangzhou (Guangdong, China). Twenty environmental factors including topography, light, and soil properties were used to quantify the effects of urbanization. Vegetation data and soil properties were collected from 30 400-m(2) plots at 6 study sites in urban and rural areas. The difference of plant species diversity and PFTs of remnant forests between urban and rural areas were analyzed. To discern the complex relationships, multivariate statistical analyses (e.g., canonical correspondence analysis and regression analysis) were employed. Pioneer species and stress-tolerant species can survive and vigorously establish their population dominance in the urban environment. The native herb diversity was lower in urban forests than in rural forests. Urban forests tend to prefer the species with Mesophanerophyte life form. In contrast, species in rural forests possessed Chamaephyte and Nanophanerophyte life forms and gravity/clonal growth dispersal mode. Soil pH and soil nutrients (K, Na, and TN) were positively related to herb diversity, while soil heavy metal concentrations (Cu) were negatively correlated with herb diversity. The herb plant species diversity declines and the species in the remnant forests usually have stress-tolerant functional traits in response to urbanization. The factors related to urbanization such as soil acidification, nutrient leaching, and heavy metal pollution were important in controlling the plant diversity in the forests along the urban-rural gradients. Urbanization affects the structure and functional traits of remnant subtropical evergreen broad-leaved forests.

  6. Long-lived but Discontinuous Hotspot Volcanism of the South Pacific Mantle

    Science.gov (United States)

    Koppers, A.; Staudigel, H.; Wijbrans, J.; Pringle, M.

    2001-12-01

    Hotspots of the South Pacific have been operating since the Early Cretaceous. We present evidence that their heterogeneous geochemical character and, hence, their respective HIMU-EMI-EMII mantle sources, can be traced back into the West Pacific Seamount Province (WPSP) using plate tectonic reconstructions. This implies that the HIMU, EMI and EMII mantle components are enduring features within the Earth's mantle, at least, for the last 140 Myr. These correlations are eminent on the scale of the WPSP and the South Pacific Thermal and Isotopic Anomaly (SOPITA) although the evolution of individual hotspots emerges notably more complicated. Hotspots in the WPSP and SOPITA mantle regions typically display intermittent volcanic activity, longevities shorter than 70 Myr, superposition of hotspot volcanism, and indirectly the motion of their mantle plumes through time. In our plate tectonic reconstructions, we use 40Ar/39Ar seamount ages and Sr-Nd-Pb isotopic signatures to map out Cretaceous hotspot volcanism in the WPSP and to characterize its evolution with respect to the currently active hotspots in the SOPITA region. EM-type Magellan, Anewetak, Ralik and Ratak seamount trails can be traced back to the magmatic activity of the Macdonald, Rurutu and Rarotonga hotspots during the Cretaceous; the HIMU-type seamounts within the Southern Wake seamount trail (97-120 Ma) most likely originated from the Mangaia-Rurutu "hot-line" in the Cook-Austral Islands. The Typhoon and Japanese guyots terminated their volcanism during the Early Cretaceous and have no presently active hot spot. However, the currently active Samoan, Society, Pitcairn and Marquesas hotspots may be traced back only to about 30-70 Myr and lack long-lived counterparts in the WPSP. These hotspots may have become active over the last 30-70 Myr only. All in all hotspot volcanism in the South Pacific seems to be controlled by a "superplume" type of mantle convection giving rise to multiple weak mantle plumes, each

  7. Seasonal prediction of the South Pacific Convergence Zone in the austral wet season

    Science.gov (United States)

    Charles, A. N.; Brown, J. R.; Cottrill, A.; Shelton, K. L.; Nakaegawa, T.; Kuleshov, Y.

    2014-11-01

    The position and orientation of the South Pacific Convergence Zone (SPCZ), modulated by the El Niño-Southern Oscillation (ENSO), determine many of the potentially predictable interannual variations in rainfall in the South Pacific region. In this study, the predictability of the SPCZ in austral summer is assessed using two coupled (ocean-atmosphere) global circulation model (CGCM)-based seasonal prediction systems: the Japan Meteorological Agency's Meteorological Research Institute Coupled Ocean-Atmosphere General Circulation Model (JMA/MRI-CGCM) and the Australian Bureau of Meteorology's Predictive Ocean-Atmosphere Model for Australia (POAMA-M24). Forecasts of austral summer rainfall, initialized in November are assessed over the period 1980-2010. The climatology of CGCM precipitation in the SPCZ region compares favorably to rainfall analyses over subsets of years characterizing different phases of ENSO. While the CGCMs display biases in the mean SPCZ latitudes, they reproduce interannual variability in austral summer SPCZ position indices for forecasts out to 4 months, with temporal correlations greater than 0.6. The summer latitude of the western branch of the SPCZ is predictable with correlations of the order of 0.6 for forecasts initialized as early as September, while the correlation for the eastern branch only exceeds 0.6 for forecasts initialized in November. Encouragingly, the models are able to simulate the large displacement of the SPCZ during zonal SPCZ years 1982-1983, 1991-1992, and 1997-1998.

  8. Changes in the South Pacific Convergence Zone in IPCC AR4 future climate projections

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Josephine R.; Moise, Aurel F.; Delage, Francois P. [Bureau of Meteorology, Centre for Australian Weather and Climate Research, Melbourne (Australia)

    2012-07-15

    The response of the South Pacific Convergence Zone (SPCZ) to climate change is examined using simulations from 16 coupled climate models under the A2 emission scenario carried out for the Intergovernmental Panel on Climate Change Fourth Assessment Report. Characteristics of the austral summer SPCZ in the late twenty-first century are compared with the late twentieth century: the orientation and latitude of the SPCZ precipitation band; the area and intensity of precipitation within the SPCZ; and the eastern extent of the SPCZ. Changes in the SPCZ position are examined using a simple linear fit to the band of maximum precipitation and using a ''pattern matching'' technique. Both techniques find no consistent shift in the slope or mean latitude of the austral summer SPCZ. However, many models simulate a westward shift in the eastern edge of the SPCZ in austral summer, with reduced precipitation to the east of around 150 W. The westward contraction of the SPCZ is associated with a strengthening of the trade winds in the southeast Pacific and an increased zonal sea surface temperature gradient across the South Pacific. The majority of models simulate an increase in the area of the SPCZ and in mean and maximum precipitation within the SPCZ, defined by a 6 mm/day precipitation threshold, consistent with increased moisture convergence in a warmer climate. Changes in the SPCZ response to ENSO are examined using ENSO precipitation composites. The SPCZ has a reduced slope and is shifted towards the equator in the A2 multi-model mean El Nino composite. (orig.)

  9. Process evaluation of a walking programme delivered through the workplace in the South Pacific island Vanuatu.

    Science.gov (United States)

    Siefken, Katja; Schofield, Grant; Schulenkorf, Nico

    2015-06-01

    The South Pacific region is experiencing significant rates of chronic diseases. Well-evaluated health promotion programmes are needed as a central piece of a strategic solution. Just as important as the evaluation itself is how that evaluation outcome can be communicated for future programme use by local programme planners. The objective of this study is to evaluate a physical activity (PA) programme that was designed for Pacific women in urban Vanuatu, and subsequently to develop new techniques to display data that support the understanding and communication of programme success and challenges. Data collection methods included quantitative Likert scale questions and qualitative open-ended questions. A new analysis technique visualises open-ended process evaluation data. We present themes using word sizes proportional to the frequency of the themes identified through thematic analysis. The Likert scale technique revealed little meaningful information; almost all participants rated most elements of the programme highly. This may be related to Pacific people being frequently inclined to assent with external ideas. Open-ended questions provided more significant insights. For example, we found a stronger change in eating habits (68.9%) than in exercise behaviour (28.2%). We present an evaluation of the first pedometer-based PA intervention in the Pacific and respond to the paucity of process evaluations that have been carried out in the context of low- and middle-income countries. Moreover, the new thematic data visualisation (TDV) approach may aid in understanding complex and cluttered data in a constructive and coordinated way; we present a new approach in health promotion research. © The Author(s) 2014.

  10. Chemical, optical and other data collected aboard the MELVILLE during cruise MV1102 in the South Atlantic Ocean and South Pacific Ocean from 2011-02-19 to 2011-03-14 (NCEI Accession 0130849)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0130849 includes chemical, optical and other data collected aboard the MELVILLE during cruise MV1102 in the South Atlantic Ocean and South Pacific...

  11. Application of Synthetic Storm Technique for Diurnal and Seasonal Variation of Slant Path Ka-Band Rain Attenuation Time Series over a Subtropical Location in South Africa

    Directory of Open Access Journals (Sweden)

    J. S. Ojo

    2015-01-01

    Full Text Available As technology advances and more demands are on satellite services, rain-induced attenuation still creates one of the most damaging effects of the atmosphere on the quality of radio communication signals, especially those operating above 10 GHz. System designers therefore require statistical information on rain-induced attenuation over the coverage area in order to determine the appropriate transmitter and receiver characteristics to be adopted. This paper presents results on the time-varying rain characterization and diurnal variation of slant path rain attenuation in the Ka-band frequency simulated with synthetic storm techniques over a subtropical location in South Africa using 10-year rain rate time-series data. The analysis is based on the CDF of one-minute rain rate; time-series seasonal variation of rain rate observed over four time intervals: 00:00–06:00, 06:00–12:00, 12:00–18:00, and 18:00–24:00; diurnal fades margin; and diurnal variation of rain attenuation. Comparison was also made between the synthesized values and measured attenuation data. The predicted statistics are in good agreement with those obtained from the propagation beacon measurement in the area. The overall results will be needed for an acceptable planning that can effectively reduce the fade margin to a very low value for an optimum data communication over this area.

  12. Autotrophic and heterotrophic microbial activity in sediments underlying the ultra-oligotrophic South Pacific Gyre

    Science.gov (United States)

    Ferdelman, T. G.; Ziebis, W.; Patel, A.; Krupke, A.; IODP Expedition 329 Shipboard Scientific Party, T.; IODP Expedition 329 Shipboard Science Party

    2011-12-01

    The South Pacific Gyre (SPG) comprises Earth's largest oceanic province and represents one of the largest scientifically unexplored region of seafloor. The sediments underlying this ultra-oligotrophic gyre exhibit extreme low sedimentation rates and cell abundances at or near the detection limit. Dissolved oxygen penetrations measured during the 2006-7 site survey expedition, reached depths of several meters suggesting that microbial activities in these sediments are persistently low (D'Hondt S et al. 2009, Proc. Nat. Acad. Sci.,106, 11651-11656). In 2011, IODP Expedition 329 drilled at seven sites ranging from 3739 to 5707 meters water depth and covering 6655 nautical miles across the gyre. Sediments were recovered along a northern transect (U1365 - U1368) from the gyre edge (24°S, 166°W) towards the center (28°S, 123°W), a southern transect (U1368 - U1370) back to the gyre edge (42°S, 153°W), and included a drill site just outside the gyre (U1371; 46°S, 163°W). One of the fundamental Expedition 329 objectives was to test how oceanographic factors control variation in sub-seafloor sedimentary habitats, activities and communities from gyre center to gyre margin. We present results of our post-expedition studies to evaluate metabolic activities and their distributions across the oxic South Pacific Gyre sediment ecosystem. Incubation experiments using sensitive stable and radioisotope approaches were performed onboard Expedition 329 to test for potential autotrophic versus heterotrophic metabolisms. A protocol was developed to extract and concentrate intact cells for the determination of substrate uptake and single cell analyses (e.g. nanoSIMS). Here we report results from the C-14 turnover and uptake experiments (acetate and bicarbonate). At all sites we observed C-14 acetate label turnover and oxidation to dissolved inorganic carbon. There was a trend of greater turnover of labeled acetate towards the gyre edges. Labeled acetate uptake into extracted

  13. Basin-scale transport of hydrothermal dissolved metals across the South Pacific Ocean.

    Science.gov (United States)

    Resing, Joseph A; Sedwick, Peter N; German, Christopher R; Jenkins, William J; Moffett, James W; Sohst, Bettina M; Tagliabue, Alessandro

    2015-07-09

    Hydrothermal venting along mid-ocean ridges exerts an important control on the chemical composition of sea water by serving as a major source or sink for a number of trace elements in the ocean. Of these, iron has received considerable attention because of its role as an essential and often limiting nutrient for primary production in regions of the ocean that are of critical importance for the global carbon cycle. It has been thought that most of the dissolved iron discharged by hydrothermal vents is lost from solution close to ridge-axis sources and is thus of limited importance for ocean biogeochemistry. This long-standing view is challenged by recent studies which suggest that stabilization of hydrothermal dissolved iron may facilitate its long-range oceanic transport. Such transport has been subsequently inferred from spatially limited oceanographic observations. Here we report data from the US GEOTRACES Eastern Pacific Zonal Transect (EPZT) that demonstrate lateral transport of hydrothermal dissolved iron, manganese, and aluminium from the southern East Pacific Rise (SEPR) several thousand kilometres westward across the South Pacific Ocean. Dissolved iron exhibits nearly conservative (that is, no loss from solution during transport and mixing) behaviour in this hydrothermal plume, implying a greater longevity in the deep ocean than previously assumed. Based on our observations, we estimate a global hydrothermal dissolved iron input of three to four gigamoles per year to the ocean interior, which is more than fourfold higher than previous estimates. Complementary simulations with a global-scale ocean biogeochemical model suggest that the observed transport of hydrothermal dissolved iron requires some means of physicochemical stabilization and indicate that hydrothermally derived iron sustains a large fraction of Southern Ocean export production.

  14. [Emerging viral infections in South East Asia and the Pacific region].

    Science.gov (United States)

    Barboza, P; Tarantola, A; Lassel, L; Mollet, T; Quatresous, I; Paquet, C

    2008-10-01

    The epidemiology of several viral diseases underwent profound changes in South-East Asia and Oceania over the past decades. This was due to several factors, including the geographical distribution of vectors and the viruses they transmit; increasing traveling and trade; increasing ecological and demographic pressure. We reviewed the current state of knowledge based on published sources and available epidemiological data. The review was limited to potentially emerging viruses in Southeast Asia and the Pacific reported in human cases. Dengue, Chikungunya, and Japanese Encephalitis viruses have recurred on a yearly basis with a steady increase in these regions. Ross River and Barmah viruses now appear regularly in Australia, in an increasing number of cases. Nipah virus strikes regularly with limited but deadly epidemics in Southeast Asia. Finally, infections by lyssaviruses, Kunjin, Murray Valley, or Zika viruses were also reviewed.

  15. Linked trends in the South Pacific sea ice edge and Southern Oscillation Index

    Science.gov (United States)

    Kwok, R.; Comiso, J. C.; Lee, T.; Holland, P. R.

    2016-10-01

    Previous work have shown that sea ice variability in the South Pacific is associated with extratropical atmospheric anomalies linked to the Southern Oscillation (SO). Over a 32 year period (1982-2013), our study shows that the trend in Southern Oscillation Index (SOI) is also able to quantitatively explain the trends in sea ice edge, drift, and surface winds in this region. On average two thirds of the winter ice edge trend in this sector, linked to ice drift and surface winds, could be explained by the positive SOI trend, thus subjecting the ice edge to strong decadal SO variability. If this relationship holds, the negative SOI trend prior to the recent satellite era suggests that ice edge trends opposite to that of the recent record over a similar time scale. Significant low-frequency ice edge trends, linked to the natural variability of SO, are superimposed upon any trends expected of anthropogenic forcing.

  16. New bioactive halenaquinone derivatives from South Pacific marine sponges of the genus Xestospongia.

    Science.gov (United States)

    Longeon, Arlette; Copp, Brent R; Roué, Mélanie; Dubois, Joëlle; Valentin, Alexis; Petek, Sylvain; Debitus, Cécile; Bourguet-Kondracki, Marie-Lise

    2010-08-15

    Bioassay-directed fractionation of South Pacific marine sponges of the genus Xestospongia has led to the isolation of a number of halenaquinone-type polyketides, including two new derivatives named xestosaprol C methylacetal 7 and orhalquinone 8. Chemical characterization of these two new compounds was achieved by extensive 1D and 2D NMR spectroscopic studies. Evaluation of anti-phospholipase A(2), anti-farnesyltransferase and antiplasmodial activities of this series is presented and structure/activity relationships are discussed. Orhalquinone 8 displayed a significant inhibition of both human and yeast farnesyltransferase enzymes, with IC(50) value of 0.40 microM and was a moderate growth inhibitor of Plasmodium falciparum. Copyright 2010 Elsevier Ltd. All rights reserved.

  17. Bioactive indole derivatives from the South Pacific marine sponges Rhopaloeides odorabile and Hyrtios sp.

    Science.gov (United States)

    Longeon, Arlette; Copp, Brent R; Quévrain, Elodie; Roué, Mélanie; Kientz, Betty; Cresteil, Thierry; Petek, Sylvain; Debitus, Cécile; Bourguet-Kondracki, Marie-Lise

    2011-01-01

    Indole derivatives including bromoindoles have been isolated from the South Pacific marine sponges Rhopaloeides odorabile and Hyrtios sp. Their structures were established through analysis of mass spectra and 1D and 2D NMR spectroscopic data. Their potential inhibitory phospholipase A₂ (PLA₂), antioxidant and cytotoxic activities were evaluated. The new derivative 5,6-dibromo-L-hypaphorine (9) isolated from Hyrtios sp. revealed a weak bee venom PLA₂ inhibition (IC₅₀ 0.2 mM) and a significant antioxidant activity with an Oxygen Radical Absorbance Capacity (ORAC) value of 0.22. The sesquiterpene aureol (4), also isolated from Hyrtios sp., showed the most potent antioxidant activity with an ORAC value of 0.29.

  18. Bioactive Indole Derivatives from the South Pacific Marine Sponges Rhopaloeides odorabile and Hyrtios sp.

    Directory of Open Access Journals (Sweden)

    Marie-Lise Bourguet-Kondracki

    2011-05-01

    Full Text Available Indole derivatives including bromoindoles have been isolated from the South Pacific marine sponges Rhopaloeides odorabile and Hyrtios sp. Their structures were established through analysis of mass spectra and 1D and 2D NMR spectroscopic data. Their potential inhibitory phospholipase A2 (PLA2, antioxidant and cytotoxic activities were evaluated. The new derivative 5,6-dibromo-l-hypaphorine (9 isolated from Hyrtios sp. revealed a weak bee venom PLA2 inhibition (IC50 0.2 mM and a significant antioxidant activity with an Oxygen Radical Absorbance Capacity (ORAC value of 0.22. The sesquiterpene aureol (4, also isolated from Hyrtios sp., showed the most potent antioxidant activity with an ORAC value of 0.29.

  19. The role of latent heat in kinetic energy conversions of South Pacific cyclones

    Science.gov (United States)

    Kann, Deirdre M.; Vincent, Dayton G.

    1986-01-01

    The four-dimensional behavior of cyclone systems in the South Pacific Convergence Zone (SPCZ) is analyzed. Three cyclone systems, which occurred during the period from January 10-16, 1979, are examined using the data collected during the first special observing period of the FGGE. The effects of latent heating on the life cycles of the cyclones are investigated. Particular attention is given to the conversions of eddy available potential energy to eddy kinetic energy and of mean kinetic energy to eddy kinetic energy. The net radiation profile, sensible heat flux, total field of vertical motion, and latent heat component were computed. The life cycles of the cyclones are described. It is observed that the latent heating component accounts for nearly all the conversion in the three cyclones, and latent heating within the SPCZ is the major source of eddy kinetic energy for the cyclones.

  20. From the regional to the local in the Colombian South Pacific, 1780-1930

    Directory of Open Access Journals (Sweden)

    Oscar Almario García

    2009-06-01

    Full Text Available The article analyzes the strategies, the mechanisms and the institutions created by the human groups settled in the Colombian Pacific South between 1780 and 1930. The text offers an explanation of the why of its adaptation, transformation, and interchange flow, and how they achieved their own dynamic which currently constitutes a sub-regional identity in the national sphere. The author takes regional matters as his nucleus and analytical perspective. The initial contextualization of these matters is given from the historical-demographic-social dynamic of its inhabitants, of which a majority was slaves, followed by free men, and aborigines. Finally, the author analyzes with broad procedural and general strokes, the region-economy, region-state, region-markets, and region-city relationships of the object of the study from the chronological framework proposed.

  1. Confronting death: Tuvaluan Islanders, in the South Pacific, and the rising sea level

    Directory of Open Access Journals (Sweden)

    Isabel Maria Madaleno

    2012-08-01

    Full Text Available The Tuvalu Group is made of nine small low-lying coral atoll and reef islands, located in the South Pacific, about 1,100 km north of Fiji. With a total area of 26 km2, it has about 11,000 residents, generally fishermen and breadfruit, taro, pulaka and coconut subsistence farmers. The people of Tuvalu are mostly of Polynesian origin, their culture and physical type being quite homogeneous. In order to develop an ethno-geographic study, during the month of February 2010, the Portuguese Tropical Research Institute has conducted a scientific mission to the atoll of Funafuti, widely known to be endangered due to the rising sea level. The objectives of the project were twofold: to evaluate the Pacific people's awareness to climate change and, consequently, to evaluate their perception of death. The survey consisted of fifty-eight semi-structured interviews. Results have shown that nearly two thirds of the remote islanders fear not the rising sea levels, as they are mostly Christians and therefore fearless of death. They emphatically trust that Divine Providence will bet on their survival.

  2. The great canoes in the sky starlore and astronomy of the South Pacific

    CERN Document Server

    Chadwick, Stephen Robert

    2017-01-01

    Presenting spectacular photographs of astronomical objects of the southern sky, all taken by author Stephen Chadwick, this book explores what peoples of the South Pacific see when they look up at the heavens and what they have done with this knowledge. From wives killing brothers to emus rising out of the desert and great canoes in the sky, this book offers the perfect blend of science, tradition and mythology to bring to life the most famous sights in the heavens above the southern hemisphere. The authors place this starlore in the context of contemporary understandings of astronomy. The night sky of southern societies is as rich in culture as it is in stars. Stories, myths and legends based on constellations, heavenly bodies and other night sky phenomena have played a fundamental role in shaping the culture of pre-modern civilizations throughout the world. Such starlore continues to influence societies throughout the Pacific to this day, with cultures throughout the region – from Australia and New Zealand...

  3. Interdecadal variation in the extent of South Pacific tropical waters during the Younger Dryas event.

    Science.gov (United States)

    Corrège, Thierry; Gagan, Michael K; Beck, J Warren; Burr, George S; Cabioch, Guy; Le Cornec, Florence

    2004-04-29

    During the Younger Dryas event, about 12,000 years ago, the Northern Hemisphere cooled by between 2 and 10 degrees C (refs 1, 2) whereas East Antarctica experienced warming. But the spatial signature of the event in the southern mid-latitudes and tropics is less well known, as records are sparse and inconclusive. Here we present high-resolution analyses of skeletal Sr/Ca and 18O/16O ratios for a giant fossil Diploastrea heliopora coral that was preserved in growth position on the raised reef terraces of Espiritu Santo Island, Vanuatu, in the southwestern tropical Pacific Ocean. Our data indicate that sea surface temperatures in Vanuatu were on average 4.5 +/- 1.3 degrees C cooler during the Younger Dryas event than today, with a significant interdecadal modulation. The amplified annual cycle of sea surface temperatures, relative to today, indicates that cooling was caused by the compression of tropical waters towards the Equator. The positive correlation in our record between the oxygen isotope ratios of sea water and sea surface temperatures suggests that the South Pacific convergence zone, which brings 18O-depleted precipitation to the area today, was not active during the Younger Dryas period.

  4. Historical Sea Level in the South Pacific from Rescued Archives, Geodetic Measurements, and Satellite Altimetry

    Science.gov (United States)

    Aucan, J.; Merrifield, M. A.; Pouvreau, N.

    2017-10-01

    Automatic sea-level measurements in Nouméa, South Pacific, started in 1957 for the International Geophysical year. Data from this location exist in paper record for the 1957-1967 period, and in two distinct electronic records for the 1967-2005 and 2005-2015 period. In this study, we digitize the early record, and established a link between the two electronic records to create a unique, nearly 60 year-long instrumental sea-level record. This work creates one of the longest instrumental sea-level records in the Pacific Islands. These data are critical for the study of regional and interannual variations of sea level. This new data set is then used to infer rates of vertical movements by comparing it to (1) the entire satellite altimetric record (1993-2013) and (2) a global sea-level reconstruction (1957-2010). These inferred rates show an uplift of 1.3-1.4 mm/year, opposite to the currently accepted values of subsidence found in the geological and geodetic literature, and underlie the importance of systematic geodetic measurements at, over very near tide gauges.

  5. Open ocean DMS air/sea fluxes over the eastern South Pacific Ocean

    Science.gov (United States)

    Marandino, C. A.; de Bruyn, W. J.; Miller, S. D.; Saltzman, E. S.

    2009-01-01

    Air/sea fluxes of dimethylsulfide (DMS) were measured by eddy correlation over the Eastern South Pacific Ocean during January 2006. The cruise track extended from Manzanillo, Mexico, along 110° W, to Punta Arenas, Chile. Bulk air and surface ocean DMS levels were also measured and gas transfer coefficients (kDMS) were computed. Air and seawater DMS measurements were made using chemical ionization mass spectrometry (API-CIMS) and a gas/liquid membrane equilibrator. Mean surface seawater DMS concentrations were 3.8±2.2 nM and atmospheric mixing ratios were 340±370 ppt. The air/sea flux of DMS was uniformly out of the ocean, with an average value of 12±15 μmol m-2 d-1. Sea surface concentration and flux were highest around 15° S, in a region influenced by shelf waters and lowest around 25° S, in low chlorophyll gyre waters. The DMS gas transfer coefficient exhibited a linear wind speed-dependence over the wind speed range of 1 to 9 m s-1. This relationship is compared with previously measured estimates of k from DMS, CO2, and dual tracer data from the Atlantic and Pacific Ocean, and with the NOAA/COARE gas transfer model. The model generated slope of k vs. wind speed is at the low end of those observed in previous DMS field studies.

  6. Current meter data from moored current meter casts in the South Pacific Ocean as part of the Equatorial Pacific Ocean Climate Studies (EPOCS) project from 1981-11-21 to 1983-11-20 (NODC Accession 8500258)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Current meter data were collected using moored current meter casts in the South Pacific Ocean from November 21, 1981 to November 20, 1983. Data were submitted by...

  7. Plankton, temperature and other measurements found in dataset OSD taken from the BONDY, BAP EXPLORADOR and other platforms in the Coastal S Pacific, South Pacific and other locations from 1961 to 1965 (NODC Accession 0001140)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Physical, nutrients, and plankton data were collected using plankton net and bottle casts in the South Pacific Ocean from 01 August 1961 to 09 September 1965. Data...

  8. Pressure, temperature, and salinity collected by CTDs from ships in the North Pacific and South Pacific Oceans from 6/30/1999 to 12/14/1999 (NODC Accession 0000003)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile and pressure data were collected using CTD casts in the North/South Pacific Ocean from NOAA Ship RONALD H. BROWN AND NOAA Ship KA'IMIMOANA from...

  9. Physical, profile and underway data collected aboard the ROGER REVELLE during cruise RR1213 in the North Pacific Ocean and South Pacific Ocean from 2012-10-04 to 2012-11-05 (NCEI Accession 0129851)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0129851 includes physical, profile and underway data collected aboard the ROGER REVELLE during cruise RR1213 in the North Pacific Ocean and South...

  10. Nitrous oxide cycling in the water column and sediments of the oxygen minimum zone, eastern subtropical North Pacific, Southern California, and Northern Mexico (23°N-34°N)

    Science.gov (United States)

    Townsend-Small, Amy; Prokopenko, Maria G.; Berelson, William M.

    2014-05-01

    Identifying sources and sinks of N2O can illuminate N cycling processes in marine systems, particularly where changes in dissolved O2 can lead to changes in N cycling pathways (i.e., nitrification versus denitrification). We measured N2O and NO3- concentration and their stable isotope ratios (δ15N and δ18O) in the water column and sediments of the oxygen minimum zone in the nearshore eastern subtropical North Pacific (23°N-34°N). Atmospheric efflux of N2O ranged from 2.2 to 17.9 μmol m-2 d-1 or about 2-20 times higher than in oxygenated regions of the North Pacific. Surface waters were a source of 15N-depleted and 18O-enriched N2O to the atmosphere, indicating a bacterial, not archaeal, nitrification N2O source. Stable isotopes indicated that nitrification in both surface and intermediate waters (˜0-200 m) was the major source of N2O in this study area, with denitrification acting as a small N2O sink in strongly O2-depleted waters. Denitrification had a larger impact on observed patterns of N2O and NO3- concentrations and isotope ratios in the southern oxygen minimum zone. Sediments were generally neutral or a weak sink for N2O, with only one site (Soledad basin) showing a positive efflux of +3.5 ± 1.0 μmol N2O-N m-2 d-1. Sediment fluxes of N2O at all sites were several orders of magnitude smaller than fluxes of dinitrogen, nitrate, and ammonium measured in previous studies and did not appear to impact water column N2O concentrations. N2O was less than 0.1% of the N2 efflux from sedimentary denitrification.

  11. Staphylococcus aureus 'Down Under': contemporary epidemiology of S. aureus in Australia, New Zealand, and the South West Pacific.

    Science.gov (United States)

    Williamson, D A; Coombs, G W; Nimmo, G R

    2014-07-01

    The clinical and molecular epidemiology of Staphylococcus aureus disease has changed considerably over the past two decades, particularly with the emergence and spread of community-associated methicillin-resistant S. aureus (CA-MRSA) clones. Indeed, some of the first global descriptions of CA-MRSA were from remote indigenous communities in Western Australia, and from Pacific Peoples in New Zealand. The epidemiology of S. aureus infections in the South West Pacific has several unique features, largely because of the relative geographical isolation and unique indigenous communities residing in this region. In particular, a number of distinct CA-MRSA clones circulate in Australia and New Zealand, such as sequence type (ST) 93 methicillin-resistant S. aureus (MRSA) (Queensland clone) and clonal complex 75 S. aureus (Staphylococcus argenteus) in Australia, and ST30 MRSA (Southwest Pacific clone) in New Zealand. In addition, there is a disproportionate burden of S. aureus disease in indigenous paediatric populations, particularly in remote Aboriginal communities in Australia, and in Pacific Peoples and Maori in New Zealand. In this review, we provide a contemporary overview of the clinical and molecular epidemiology of S. aureus disease in the South West Pacific region, with a particular focus on features distinct to this region. © 2014 The Authors Clinical Microbiology and Infection © 2014 European Society of Clinical Microbiology and Infectious Diseases.

  12. A simple mixing explanation for late Pleistocene changes in the Pacific-South Atlantic benthic δ13C gradient

    Directory of Open Access Journals (Sweden)

    L. E. Lisiecki

    2010-05-01

    Full Text Available The fact that the deep-ocean benthic δ13C minimum shifted from the North Pacific to the South Atlantic during the Last Glacial Maximum is often interpretted as evidence of a change in deep water circulation, such as the development of deep water ventilation in the North Pacific or a decrease in Southern Ocean overturning. This study re-evaluates the implications of changes in benthic δ13C gradients by comparing Pacific Deep Water (PDW δ13C measurements with the values expected for the null hypothesis that PDW ventilation sources remained unchanged throughout the Late Pleistocene. The δ13C compositions of PDW, Northern Component Water (NCW and Southern Component Water (SCW are estimated from regional benthic δ13C stacks of 3–6 sites. Changes in PDW δ13C and PDW-SCW δ13C gradients over the past 800 kyr are found to be well described by a constant mixture of 60% NCW and 40% SCW plus a constant Pacific remineralization offset of −0.5‰. Thus, a change in PDW ventilation cannot be inferred solely on the basis of changes in the Pacific-South Atlantic benthic δ13C gradient.

  13. Diel Vertical Dynamics of Gelatinous Zooplankton (Cnidaria, Ctenophora and Thaliacea in a Subtropical Stratified Ecosystem (South Brazilian Bight.

    Directory of Open Access Journals (Sweden)

    Miodeli Nogueira Júnior

    Full Text Available The diel vertical dynamics of gelatinous zooplankton in physically stratified conditions over the 100-m isobath (~110 km offshore in the South Brazilian Bight (26°45'S; 47°33'W and the relationship to hydrography and food availability were analyzed by sampling every six hours over two consecutive days. Zooplankton samples were taken in three depth strata, following the vertical structure of the water column, with cold waters between 17 and 13.1°C, influenced by the South Atlantic Central Water (SACW in the lower layer (>70 m; warm (>20°C Tropical Water in the upper 40 m; and an intermediate thermocline with a deep chlorophyll-a maximum layer (0.3-0.6 mg m-3. Two distinct general patterns were observed, emphasizing the role of (i physical and (ii biological processes: (i a strong influence of the vertical stratification, with most zooplankton absent or little abundant in the lower layer. The influence of the cold SACW on the bottom layer apparently restricted the vertical occupation of most species, which typically inhabit epipelagic warm waters. Even among migratory species, only a few (Aglaura hemistoma, Abylopsis tetragona eudoxids, Beroe sp., Thalia democratica, Salpa fusiformis crossed the thermocline and reached the bottom layer. (ii A general tendency of partial migrations, with variable intensity depending on the different species and developmental stages; populations tended to be more widely distributed through the water column during daylight, and to become more aggregated in the upper layer during the night, which can be explained based on the idea of the "hunger-satiation hypothesis", maximizing feeding and minimizing the chances of being predated.

  14. Diel Vertical Dynamics of Gelatinous Zooplankton (Cnidaria, Ctenophora and Thaliacea) in a Subtropical Stratified Ecosystem (South Brazilian Bight).

    Science.gov (United States)

    Nogueira Júnior, Miodeli; Brandini, Frederico Pereira; Codina, Juan Carlos Ugaz

    2015-01-01

    The diel vertical dynamics of gelatinous zooplankton in physically stratified conditions over the 100-m isobath (~110 km offshore) in the South Brazilian Bight (26°45'S; 47°33'W) and the relationship to hydrography and food availability were analyzed by sampling every six hours over two consecutive days. Zooplankton samples were taken in three depth strata, following the vertical structure of the water column, with cold waters between 17 and 13.1°C, influenced by the South Atlantic Central Water (SACW) in the lower layer (>70 m); warm (>20°C) Tropical Water in the upper 40 m; and an intermediate thermocline with a deep chlorophyll-a maximum layer (0.3-0.6 mg m-3). Two distinct general patterns were observed, emphasizing the role of (i) physical and (ii) biological processes: (i) a strong influence of the vertical stratification, with most zooplankton absent or little abundant in the lower layer. The influence of the cold SACW on the bottom layer apparently restricted the vertical occupation of most species, which typically inhabit epipelagic warm waters. Even among migratory species, only a few (Aglaura hemistoma, Abylopsis tetragona eudoxids, Beroe sp., Thalia democratica, Salpa fusiformis) crossed the thermocline and reached the bottom layer. (ii) A general tendency of partial migrations, with variable intensity depending on the different species and developmental stages; populations tended to be more widely distributed through the water column during daylight, and to become more aggregated in the upper layer during the night, which can be explained based on the idea of the "hunger-satiation hypothesis", maximizing feeding and minimizing the chances of being predated.

  15. Tales from the South (and West) Pacific in the Common Era: A Climate Proxy Perspective (Invited)

    Science.gov (United States)

    Quinn, T. M.; Taylor, F. W.; Partin, J. W.; Maupin, C. R.; Hereid, K. A.; Gorman, M. K.

    2010-12-01

    The southwest Pacific is a major source of tropical climate variability through heat and moisture exchanges associated with the Western Pacific Warm Pool (WPWP) and the South Pacific Convergence Zone (SPCZ). These variations are especially significant at the annual, interannual (El Niño-Southern Oscillation, ENSO), and multi-decadal timescales. Gridded SST data products are available in the pre-satellite era in this region for the past ~130 years, although data density is a significant issue for the older half of these records. Time series of salinity (SSS) and rainfall from this region are exceedingly rare. Thus, climate proxy records must be used to reconstruct SST, SSS, and rainfall variations in the Common Era (CE) in the tropical Pacific. The analytical laboratory for paleoclimate studies at UT has focused its research efforts into producing climate proxy time series from southwest tropical Pacific using modern and fossil corals, and speleothems. Our most recent results are summarized in this presentation, although much of this work is still in progress. Coral climate records have been generated from Sabine Bank, Vanuatu (16°S, 166°E) and Misima Island, Papua New Guinea (10.6°S, 152.8°E). The Vanuatu coral record of monthly resolved Sr/Ca variations extends back to the late 18th century. All strong ENSO warm phase events of the 20th century observed in the instrumental record are also observed in the coral record. We note that several ENSO warm phase events in the 19th century portion of the coral record are comparable in size to that recorded in response to the 1982/1983 and 1997/1998 events. The Misima coral record of monthly resolved δ18O and Sr/Ca variations spans the interval ~1414-1645 CE — the heart of the Little Ice Age. Amplitude modulation of interannual variability is observed in this LIA record, much like what is observed during the relatively quiescent period of 1920-1950 in the 20th century instrumental and proxy records of ENSO. However

  16. Interannual and Decadal Changes in Salinity in the Oceanic Subtropical Gyres

    Science.gov (United States)

    Bulusu, Subrahmanyam

    2017-04-01

    There is evidence that the global water cycle has been undergoing an intensification over several decades as a response to increasing atmospheric temperatures, particularly in regions with skewed evaporation - precipitation (E-P) patterns such as the oceanic subtropical gyres. Moreover, observational data (rain gauges, etc.) are quite sparse over such areas due to the inaccessibility of open ocean regions. In this work, a comparison of observational and model simulations are conducted to highlight the potential applications of satellite derived salinity from NASA Aquarius Salinity mission, NASA Soil Moisture and Ocean Salinity (SMOS), and ESA's Soil Moisture Active Passive (SMAP). We explored spatial and temporal salinity changes (and trends) in surface and subsurface in the oceanic subtropical gyres using Argo floats salinity data, Simple Ocean Data Assimilation (SODA) reanalysis, Estimating the Circulations & Climate of the Ocean GECCO (German ECCO) model simulations, and Hybrid Coordinate Ocean Model (HYCOM). Our results based on SODA reanalysis reveals that a positive rising trend in sea surface salinity in the subtropical gyres emphasizing evidence for decadal intensification in the surface forcing in these regions. Zonal drift in the location of the salinity maximum of the south Pacific, north Atlantic, and south Indian regions implies a change in the mean near-surface currents responsible for advecting high salinity waters into the region. Also we found out that an overall salinity increase within the mixed layer, and a subsurface salinity decrease at depths greater than 200m in the global subtropical gyres over 61 years. We determine that freshwater fluxes at the air-sea interface are the primary drivers of the sea surface salinity (SSS) signature over these open ocean regions by quantifying the advective contribution within the surface layer. This was demonstrated through a mixed layer salinity budget in each subtropical gyre based on the vertically

  17. Variability in warm-season atmospheric circulation and precipitation patterns over subtropical South America: relationships between the South Atlantic convergence zone and large-scale organized convection over the La Plata basin

    Science.gov (United States)

    Mattingly, Kyle S.; Mote, Thomas L.

    2017-01-01

    Warm-season precipitation variability over subtropical South America is characterized by an inverse relationship between the South Atlantic convergence zone (SACZ) and precipitation over the central and western La Plata basin of southeastern South America. This study extends the analysis of this "South American Seesaw" precipitation dipole to relationships between the SACZ and large, long-lived mesoscale convective systems (LLCSs) over the La Plata basin. By classifying SACZ events into distinct continental and oceanic categories and building a logistic regression model that relates LLCS activity across the region to continental and oceanic SACZ precipitation, a detailed account of spatial variability in the out-of-phase coupling between the SACZ and large-scale organized convection over the La Plata basin is provided. Enhanced precipitation in the continental SACZ is found to result in increased LLCS activity over northern, northeastern, and western sections of the La Plata basin, in association with poleward atmospheric moisture flux from the Amazon basin toward these regions, and a decrease in the probability of LLCS occurrence over the southeastern La Plata basin. Increased oceanic SACZ precipitation, however, was strongly related to reduced atmospheric moisture and decreased probability of LLCS occurrence over nearly the entire La Plata basin. These results suggest that continental SACZ activity and large-scale organized convection over the northern and eastern sections of the La Plata basin are closely tied to atmospheric moisture transport from the Amazon basin, while the warm coastal Brazil Current may also play an important role as an evaporative moisture source for LLCSs over the central and western La Plata basin.

  18. Effects of season, browse species and polyethylene glycol addition on gas production kinetics of forages in the subhumid subtropical savannah, South Africa.

    Science.gov (United States)

    Basha, Nasreldin A D; Scogings, Peter F; Nsahlai, Ignatius V

    2013-04-01

    This study was conducted to investigate the effects of season, species and polyethylene glycol addition on gas production (GP) and GP kinetic parameters by in vitro incubation (72 h) of five plant species from the subhumid subtropical savannah, South Africa. Plant species used were Acacia natalitia, Acacia nilotica, Dichrostachys cinerea, Scutia myrtina and Chromolaena odorata, leaves of which were harvested during the dry (June/July), early wet (November/December) and late wet (February/March) seasons. An automated in vitro gas production technique was used in two experiments carried out with nine replicates. The first experiment was to test the effect of season and species, while the second experiment tested the effect of tannins using polyethylene glycol 4000 (PEG). The PEG treatment was applied to samples in the early wet and late wet seasons. There were wide variations among seasons and species in crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (ADF) and condensed tannin (CT). Season and species affected the maximum GP and GP kinetic parameters. During the three seasons, C. odorata had the highest CP (186-226 g kg(-1) dry matter (DM)) and GP (87-104 mL g(-1) DM) and S. myrtina had the lowest CP (105-129 g kg(-1) DM), while A. nilotica, A. natalitia, D. cinerea and S. myrtina had similar and low GP (23-50 mL g(-1) DM). The maximum GP, its degradation rate and GP from the soluble fraction were positively correlated with CP both without and with PEG. With PEG, GP from the soluble fraction was negatively correlated with NDF, ADL and CT; without PEG, it was negatively correlated with CT. Both season and species affected the GP parameters. The addition of PEG emphasises that the inhibitory effect of tannins on rumen microbes was greater for all but C. odorata, confirming that these browse species can be used as feed supplements. © 2012 Society of Chemical Industry.

  19. The bladed Bangiales (Rhodophyta) of the South Eastern Pacific: Molecular species delimitation reveals extensive diversity.

    Science.gov (United States)

    Guillemin, Marie-Laure; Contreras-Porcia, Loretto; Ramírez, María Eliana; Macaya, Erasmo C; Contador, Cristian Bulboa; Woods, Helen; Wyatt, Christopher; Brodie, Juliet

    2016-01-01

    A molecular taxonomic study of the bladed Bangiales of the South Eastern Pacific (coast of Chile) was undertaken based on sequence data of the mitochondrial COI and chloroplast rbcL for 193 specimens collected from Arica (18°S) in the north to South Patagonia (53°S) in the south. The results revealed for the first time that four genera, Porphyra, Pyropia, Fuscifolium and Wildemania were present in the region. Species delimitation was determined based on a combination of a General Mixed Yule Coalescence model (GMYC) and Automatic Barcode Gap Discovery (ABGD) coupled with detection of monophyly in tree reconstruction. The overall incongruence between the species delimitation methods within each gene was 29%. The GMYC method led to over-splitting groups, whereas the ABGD method had a tendency to lump groups. Taking a conservative approach to the number of putative species, at least 18 were recognized and, with the exception of the recently described Pyropia orbicularis, all were new to the Chilean flora. Porphyra and Pyropia were the most diverse genera with eight 'species' each, whereas only a 'single' species each was found for Fuscifolium and Wildemania. There was also evidence of recently diverging groups: Wildemania sp. was distinct but very closely related to W. amplissima from the Northern Hemisphere and raises questions in relation to such disjunct distributions. Pyropia orbicularis was very closely related to two other species, making species delimitation very difficult but provides evidence of an incipient speciation. The difference between the 'species' discovered and those previously reported for the region is discussed in relation to the difficulty of distinguishing species based on morphological identification. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. A Reconstruction of Subtropical Western North Pacific SST Variability Back to 1578, Based on a Porites Coral Sr/Ca Record from the Northern Ryukyus, Japan

    Science.gov (United States)

    Kawakubo, Y.; Alibert, C.; Yokoyama, Y.

    2017-12-01

    We present a seasonal reconstruction of sea surface temperature (SST) from 1578 to 2008, based on a Porites coral Sr/Ca record from the northern Ryukyus, within the Kuroshio southern recirculation gyre. Interannual SST anomalies are generally 0.5°C, making Sr/Ca-derived SST reconstructions a challenging task. Replicate measurements along adjacent coral growth axes, enabled by the laser ablation inductively coupled plasma mass spectrometry technique used here, give evidence of rather large uncertainties. Nonetheless, derived winter SST anomalies are significantly correlated with the Western Pacific atmospheric pattern which has a dominant influence on winter temperature in East Asia. Annual mean SSTs show interdecadal variations, notably cold intervals between 1670 and 1700 during the Maunder Minimum (MM) and between 1766 and 1788 characterized by a negative phase of the North Atlantic Oscillation. Cold summers in 1783 and 1784 coincide with the long-lasting Laki eruption that had a profound impact on the Northern Hemisphere climate, including the severe "Tenmei" famine in Japan. The decades between 1855 and 1900 are significantly cooler than the first half of the twentieth century, while those between 1700 and 1765, following the MM, are warmer than average. SST variability in the Ryukyus is only marginally influenced by the Pacific Decadal Oscillation, so that external forcing remains the main driver of low-frequency temperature changes. However, the close connection between the Kuroshio extension (KE) and its recirculation gyre suggests that decadal SST anomalies associated with the KE front also impact the Ryukyus, and there is a possible additional role for feedback of the Kuroshio-Oyashio variability to the large-scale atmosphere at decadal timescale.

  1. Biological oceanography, biogeochemical cycles, and pelagic ecosystem functioning of the east-central South Pacific Gyre: focus on Easter Island and Salas y Gómez Island

    Directory of Open Access Journals (Sweden)

    Peter von Dassow

    2014-10-01

    Full Text Available The Exclusive Economic Zone of Chile defined by Easter Island and Salas y Gómez Island is in the South Pacific Sub-tropical Gyre (SPSG, putting it at the center of the most oligotrophic and biomass poor waters in the world. Only 10 biological oceanographic expeditions have entered this zone in 105 years (19052010. We review key aspects of the plankton ecosystem and biogeochemical function relevant for the understanding of and conservation planning for marine environments. Plankton production is limited by lack of dissolved inorganic fixed nitrogen, not phosphorous. Higher organic nitrogen levels might be biologically unavailable. Short-term experiments suggested iron is not limiting, yet iron still likely limits nitrogen fixation, and thus production, at longer time scales, as the presence of nitrogen-fixers is exceptionally low compared to other ocean gyres. Plankton function is dominated by the smallest unicellular organisms, picoplankton (<3 μm in diameter. The SPSG represents a center of high biodiversity for picoplankton, as well as heterotrophic organisms such as tinntinids, siphonophores, and possibly amphipods, although data for key zooplankton, such as copepods, are lacking. Many groups exhibit negative relationships between diversity and total plankton biomass. High diversity might result from dispersal from a very large metacommunity and minimal competition within functional groups. Whether an island-mass effect causes a real or apparent increase in plankton biomass around Easter Island must be confirmed by high-resolution sampling in situ. Long-term threats to the planktonic ecosystem may include climate change-enhanced ocean stratification and plastic marine debris accumulation. Finally, priorities for future research are highlighted.

  2. Large-scale and synoptic meteorology in the south-east Pacific during the observations campaign VOCALS-REx in austral Spring 2008

    Directory of Open Access Journals (Sweden)

    T. Toniazzo

    2011-05-01

    Full Text Available We present a descriptive overview of the meteorology in the south eastern subtropical Pacific (SEP during the VOCALS-REx intensive observations campaign which was carried out between October and November 2008. Mainly based on data from operational analyses, forecasts, reanalysis, and satellite observations, we focus on spatio-temporal scales from synoptic to planetary. A climatological context is given within which the specific conditions observed during the campaign are placed, with particular reference to the relationships between the large-scale and the regional circulations. The mean circulations associated with the diurnal breeze systems are also discussed. We then provide a summary of the day-to-day synoptic-scale circulation, air-parcel trajectories, and cloud cover in the SEP during VOCALS-REx. Three meteorologically distinct periods of time are identified and the large-scale causes for their different character are discussed. The first period was characterised by significant variability associated with synoptic-scale systems interesting the SEP; while the two subsequent phases were affected by planetary-scale disturbances with a slower evolution. The changes between initial and later periods can be partly explained from the regular march of the annual cycle, but contributions from subseasonal variability and its teleconnections were important. Across the whole of the two months under consideration we find a significant correlation between the depth of the inversion-capped marine boundary layer (MBL and the amount of low cloud in the area of study. We discuss this correlation and argue that at least as a crude approximation a typical scaling may be applied relating MBL and cloud properties with the large-scale parameters of SSTs and tropospheric temperatures. These results are consistent with previously found empirical relationships involving lower-tropospheric stability.

  3. Blue whale population structure along the eastern South Pacific Ocean: evidence of more than one population.

    Science.gov (United States)

    Torres-Florez, J P; Hucke-Gaete, R; LeDuc, R; Lang, A; Taylor, B; Pimper, L E; Bedriñana-Romano, L; Rosenbaum, H C; Figueroa, C C

    2014-12-01

    Blue whales (Balaenoptera musculus) were among the most intensively exploited species of whales in the world. As a consequence of this intense exploitation, blue whale sightings off the coast of Chile were uncommon by the end of the 20th century. In 2004, a feeding and nursing ground was reported in southern Chile (SCh). With the aim to investigate the genetic identity and relationship of these Chilean blue whales to those in other Southern Hemisphere areas, 60 biopsy samples were collected from blue whales in SCh between 2003 and 2009. These samples were genotyped at seven microsatellite loci and the mitochondrial control region was sequenced, allowing us to identify 52 individuals. To investigate the genetic identity of this suspected remnant population, we compared these 52 individuals to blue whales from Antarctica (ANT, n = 96), Northern Chile (NCh, n = 19) and the eastern tropical Pacific (ETP, n = 31). No significant differentiation in haplotype frequencies (mtDNA) or among genotypes (nDNA) was found between SCh, NCh and ETP, while significant differences were found between those three areas and Antarctica for both the mitochondrial and microsatellite analyses. Our results suggest at least two breeding population units or subspecies exist, which is also supported by other lines of evidence such as morphometrics and acoustics. The lack of differences detected between SCh/NCh/ETP areas supports the hypothesis that eastern South Pacific blue whales are using the ETP area as a possible breeding area. Considering the small population sizes previously reported for the SCh area, additional conservation measures and monitoring of this population should be developed and prioritized. © 2014 John Wiley & Sons Ltd.

  4. The Hawaii Undersea Research Laboratory's 25th Anniversary Expedition to the South Pacific

    Science.gov (United States)

    Smith, J. R.; Wiltshire, J. C.; Malahoff, A.

    2005-12-01

    The Hawaii Undersea Research Laboratory (HURL) was established by NOAA at the University of Hawaii 25 years ago as part of its National Undersea Research Program. HURL's mission is to study deep water marine processes in the Pacific Ocean through a competitive proposal and review process. The dual Pisces IV and Pisces V 2000-meter manned submersibles, an RCV-150 1000-meter ROV, and multibeam equipped support ship R/V Ka'imikai-o-Kanaloa ( KoK) were largely acquired from the petroleum industry then adapted and upgraded to carry out cutting edge scientific expeditions. These studies range from active submarine volcanoes, delicate precious coral gardens, endangered marine mammal and fisheries management, to engineering surveys and deployment of observatory systems. HURL successfully completed a major 5-month expedition to the South Pacific during March-August 2005, working in the waters of New Zealand, Tonga, American Samoa, and the U.S. Line Islands covering a distance of nearly 14,500 nautical miles. This mission was significant in both the scientific merit and scope of operations, consisting of 8 different cruise legs at 21 study sites, with 12 chief and co-chief scientists, 58 total science team participants, and completing 61 out of 56 scheduled Pisces science dives, 17 ROV dives, 5 multibeam survey areas, 6 CTD rosette deployments, and 7 instrument mooring recoveries. The $3.5 million expedition was funded by an international partnership with New Zealand agencies (GNS & NIWA) and the University of Kiel in Germany along with the NOAA Office of Exploration and National Undersea Research Program. While most of the individual cruise legs focused on active submarine volcanoes of the Tonga-Kermadec Islands Arc and the Samoan hot spot chain with their hydrothermal systems and associated biological communities, others concentrated on marine protected areas including those of American Samoa and the remote atolls of the Line Islands of the Central Pacific. These studies

  5. North and South Pacific Ocean Temperature Profile Data collected by the SCRIPPS Institute of Oceanography from 17 February 2000 to 11 August 2002 (NODC Accession 0000925)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Physical data were collected from XBT casts from the North and South Pacific Oceans. Data were collected from 17 February 2000 to 11 August 2002. Data were collected...

  6. WATER TEMPERATURE and other data from USCGC POLAR STAR in the South Pacific Ocean from 1992-11-08 to 1993-04-12 (NODC Accession 9300068)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The water depth and temperature data was collected in South Pacific Ocean as part of project Deep Freeze from ship POLAR STAR. The data was collected from November...

  7. Oceanographic profile temperature and salinity measurements collected using bottle from the ELTANIN in the South Pacific in 1969 (NODC Accession 0001458)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected using bottle casts from the ELTANIN in the South Pacific Ocean. Data were collected from 30 September 1969 to 10 November...

  8. Temperature profile data collected from multiple ships using bottle casts in the South Pacific and Indian Ocean from 04 November 1956 to 02 January 1994 (NODC Accession 0002701)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected using bottle casts from multiple ships in the South Pacific and Indian Ocean from 04 November 1956 to 02 January 1994. Data...

  9. CRED Reson 8101 multibeam backscatter data from the banktop and bank edge environments at Tutuila, American Samoa, South Pacific with 16 meter resolution in GeoTIFF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Tutuila, American Samoa, South Pacific These data provide coverage between 20 and 5000 meters. The...

  10. Zooplankton biomass data from net tows from the South Pacific Ocean from 27 January 1967 to 26 November 1967 (NODC Accession 9500090)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Zooplankton biomass data were collected from net tows from the South Pacific Ocean. Data were collected by the Bedford Institute of Oceanography (BIO) from 27...

  11. CRED Reson 8101 multibeam backscatter data from the banktop and bank edge environments at Tutuila, American Samoa, South Pacific 16 meter resolution in netCDF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Tutuila, American Samoa, South Pacific These data provide coverage between 20 and 5000 meters. The...

  12. CRED Reson 8101 multibeam backscatter data from the banktop and bank edge environments at Tutuila, American Samoa, South Pacific with 1 meter resolution in netCDF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Tutuila, American Samoa, South Pacific These data provide coverage between 20 and 5000 meters. The...

  13. CRED Reson 8101 multibeam backscatter data from the lagoon environment at Rose Island, American Samoa, South Pacific with 1 meter resolution in netCDF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Rose Island, American Samoa, South Pacific These data provide coverage between 20 and 5000 meters....

  14. CRED Reson 8101 multibeam backscatter data from the banktop and bank edge environments at Tutuila, American Samoa, South Pacific with 1 meter resolution in GeoTIFF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Tutuila, American Samoa, South Pacific These data provide coverage between 20 and 5000 meters. The...

  15. CRED Simrad em300 multibeam backscatter data from the submarine slope environment at Rose Island, American Samoa, South Pacific with 5 meter resolution in netCDF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Rose Island, American Samoa, South Pacific. These data provide coverage between 20 and 5000...

  16. Temperature, salinity, nutrient, primary production, and meteorological data collected by bottle in the South Pacific Ocean from 1/16/1962 - 8/2/1964 (NODC Accession 0000092)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile, nutrients, and other data were collected using net and bottle casts from the HUAYAIPE and ST JUDE in the South Pacific Ocean. Data were...

  17. Temperature Data From AUSTRALIA STAR and Other Platforms From Indian Ocean and South Pacific Ocean From 19860929 to 19890106 (NODC Accession 8900196)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature data from Australia Star and other ships from Indian Ocean and South Pacific Ocean from September 29, 1986 to January 6, 1989. The data were collected by...

  18. High gene flow due to pelagic larval dispersal among South Pacific archipelagos in two amphidromous gastropods (Neritomorpha: Neritidae).

    Science.gov (United States)

    Crandall, E D; Taffel, J R; Barber, P H

    2010-06-01

    The freshwater stream fauna of tropical oceanic islands is dominated by amphidromous species, whose larvae are transported to the ocean and develop in the plankton before recruiting back to freshwater habitat as juveniles. Because stream habitat is relatively scarce and unstable on oceanic islands, this life history would seem to favor either the retention of larvae to their natal streams, or the ability to delay metamorphosis until new habitat is encountered. To distinguish between these hypotheses, we used population genetic methods to estimate larval dispersal among five South Pacific archipelagos in two amphidromous species of Neritid gastropod (Neritina canalis and Neripteron dilatatus). Sequence data from mitochondrial cytochrome oxidase I (COI) revealed that neither species is genetically structured throughout the Western Pacific, suggesting that their larvae have a pelagic larval duration (PLD) of at least 8 weeks, longer than many marine species. In addition, the two species have recently colonized isolated Central Pacific archipelagos in three independent events. Since colonization, there has been little or no gene flow between the Western and Central Pacific archipelagos in N. canalis, and high levels of gene flow across the same region in N. dilatatus. Both species show departures from neutrality and recent dates for colonization of the Central Pacific archipelagos, which is consistent with frequent extinction and recolonization of stream populations in this area. Similar results from other amphidromous species suggest that unstable freshwater habitats promote long-distance dispersal capabilities.

  19. Comparative metagenomic analysis of a microbial community residing at a depth of 4,000 meters at station ALOHA in the North Pacific subtropical gyre.

    Science.gov (United States)

    Konstantinidis, Konstantinos T; Braff, Jennifer; Karl, David M; DeLong, Edward F

    2009-08-01

    The deep sea (water depth of >2,000 m) represents the largest biome on Earth. Yet relatively little is known about its microbial community's structure, function, and adaptation to the cold and deep biosphere. To provide further genomic insights into deep-sea planktonic microbes, we sequenced a total of approximately 200 Mbp of a random whole-genome shotgun (WGS) library from a microbial community residing at a depth of 4,000 m at Station ALOHA in the Pacific Ocean and compared it to other available WGS sequence data from surface and deep waters. Our analyses indicated that the deep-sea lifestyle is likely facilitated by a collection of very subtle adaptations, as opposed to dramatic alterations of gene content or structure. These adaptations appear to include higher metabolic versatility and genomic plasticity to cope with the sparse and sporadic energy resources available, a preference for hydrophobic and smaller-volume amino acids in protein sequences, unique proteins not found in surface-dwelling species, and adaptations at the gene expression level. The deep-sea community is also characterized by a larger average genome size and a higher content of "selfish" genetic elements, such as transposases and prophages, whose propagation is apparently favored by more relaxed purifying (negative) selection in deeper waters.

  20. Comparative Metagenomic Analysis of a Microbial Community Residing at a Depth of 4,000 Meters at Station ALOHA in the North Pacific Subtropical Gyre▿ †

    Science.gov (United States)

    Konstantinidis, Konstantinos T.; Braff, Jennifer; Karl, David M.; DeLong, Edward F.

    2009-01-01

    The deep sea (water depth of >2,000 m) represents the largest biome on Earth. Yet relatively little is known about its microbial community's structure, function, and adaptation to the cold and deep biosphere. To provide further genomic insights into deep-sea planktonic microbes, we sequenced a total of ∼200 Mbp of a random whole-genome shotgun (WGS) library from a microbial community residing at a depth of 4,000 m at Station ALOHA in the Pacific Ocean and compared it to other available WGS sequence data from surface and deep waters. Our analyses indicated that the deep-sea lifestyle is likely facilitated by a collection of very subtle adaptations, as opposed to dramatic alterations of gene content or structure. These adaptations appear to include higher metabolic versatility and genomic plasticity to cope with the sparse and sporadic energy resources available, a preference for hydrophobic and smaller-volume amino acids in protein sequences, unique proteins not found in surface-dwelling species, and adaptations at the gene expression level. The deep-sea community is also characterized by a larger average genome size and a higher content of “selfish” genetic elements, such as transposases and prophages, whose propagation is apparently favored by more relaxed purifying (negative) selection in deeper waters. PMID:19542347

  1. Climate Variability and Phytoplankton in the Pacific Ocean

    Science.gov (United States)

    Rousseaux, Cecile

    2012-01-01

    The effect of climate variability on phytoplankton communities was assessed for the tropical and sub-tropical Pacific Ocean between 1998 and 2005 using an established biogeochemical assimilation model. The phytoplankton communities exhibited wide range of responses to climate variability, from radical shifts in the Equatorial Pacific, to changes of only a couple of phytoplankton groups in the North Central Pacific, to no significant changes in the South Pacific. In the Equatorial Pacific, climate variability dominated the variability of phytoplankton. Here, nitrate, chlorophyll and all but one of the 4 phytoplankton types (diatoms, cyanobacteria and coccolithophores) were strongly correlated (pphytoplankton groups (chlorophytes and coccolithophores). Ocean biology in the South Pacific was not significantly correlated with MEI. During La Nina events, diatoms increased and expanded westward along the cold tongue (correlation with MEI, r=-0.81), while cyanobacteria concentrations decreased significantly (r=0.78). El Nino produced the reverse pattern, with cyanobacteria populations increasing while diatoms plummeted. The diverse response of phytoplankton in the different major basins of the Pacific suggests the different roles climate variability can play in ocean biology.

  2. Nitrous oxide production in the eastern tropical South Pacific oxygen minimum zone

    Science.gov (United States)

    Ji, Qixing; Altabet, Mark; Arevalo-Martinez, Damian; Bange, Hermann; Ma, Xiao; Marandino, Christa; Sun, Mingshuang; Grundle, Damian

    2017-04-01

    Nitrous oxide (N2O) is an important climate active trace gas that contributes to both atmospheric warming and ozone destruction, and the ocean is an important source of N2O to the atmosphere. Dissolved oxygen concentrations play an important role in regulating N2O production in the ocean, such that under low oxygen conditions major shifts in the predominant production pathways (i.e. nitrification vs. denitrification) can occur and the magnitude of production may increase substantially. To this end, major oceanic oxygen minimum zones (OMZs) are responsible for a disproportionately high amount of marine N2O production. During the October 2015 ASTRA-OMZ cruise to the eastern tropical South Pacific (ETSP), one of the three major oceanic OMZs, we measured a suite of N2O parameters which included N2O concentrations, N2O production, and natural abundance N2O isotope (i.e. del 15N and del 18O) and isotopomer (i.e. 15N site-preference) signatures. Based on the results from these measurements, our presentation will demonstrate how N2O production and the different production pathways change along the oxygen concentration gradients from the oxygenated surface waters through the oxygen minimum layer. Our data could better constrain the importance of the ETSP-OMZ as source of marine N2O. Results from this work will provide insights into how N2O cycling responds to ocean deoxygenation as a result of climate change.

  3. Are Sea Surface Temperature satellite measurements reliable proxies of lagoon temperature in the South Pacific?

    Science.gov (United States)

    Van Wynsberge, Simon; Menkes, Christophe; Le Gendre, Romain; Passfield, Teuru; Andréfouët, Serge

    2017-12-01

    In remote coral reef environments, lagoon and reef in situ measurements of temperature are scarce. Sea Surface Temperature (SST) measured by satellite has been frequently used as a proxy of the lagoon temperature experienced by coral reef organisms (TL) especially during coral bleaching events. However, the link between SST and TL is poorly characterized. First, we compared the correlation between various SST series and TL from 2012 to 2016 in three atolls and one island in the Central South Pacific Ocean. Simple linear correlation between SST and TL ranged between 0.44 and 0.97 depending on lagoons, localities of sensors, and type of SST data. High-resolution-satellite-measurements of SST inside the lagoons did not outperform oceanic SST series, suggesting that SST products are not adapted for small lagoons. Second, we modelled the difference between oceanic SST and TL as a function of the drivers of lagoon water renewal and mixing, namely waves, tide, wind, and season. The multivariate models reduced significantly the bias between oceanic SST and TL. In atoll lagoons, and probably in other hydrodynamically semi-open systems, a correction taking into account these factors is necessary when SST are used to characterize organisms' thermal stress thresholds.

  4. Seismic hazard of American Samoa and neighboring South Pacific Islands--methods, data, parameters, and results

    Science.gov (United States)

    Petersen, Mark D.; Harmsen, Stephen C.; Rukstales, Kenneth S.; Mueller, Charles S.; McNamara, Daniel E.; Luco, Nicolas; Walling, Melanie

    2012-01-01

    American Samoa and the neighboring islands of the South Pacific lie near active tectonic-plate boundaries that host many large earthquakes which can result in strong earthquake shaking and tsunamis. To mitigate earthquake risks from future ground shaking, the Federal Emergency Management Agency requested that the U.S. Geological Survey prepare seismic hazard maps that can be applied in building-design criteria. This Open-File Report describes the data, methods, and parameters used to calculate the seismic shaking hazard as well as the output hazard maps, curves, and deaggregation (disaggregation) information needed for building design. Spectral acceleration hazard for 1 Hertz having a 2-percent probability of exceedance on a firm rock site condition (Vs30=760 meters per second) is 0.12 acceleration of gravity (1 second, 1 Hertz) and 0.32 acceleration of gravity (0.2 seconds, 5 Hertz) on American Samoa, 0.72 acceleration of gravity (1 Hertz) and 2.54 acceleration of gravity (5 Hertz) on Tonga, 0.15 acceleration of gravity (1 Hertz) and 0.55 acceleration of gravity (5 Hertz) on Fiji, and 0.89 acceleration of gravity (1 Hertz) and 2.77 acceleration of gravity (5 Hertz) on the Vanuatu Islands.

  5. Environmental rock-magnetism of Cenozoic red clay in the South Pacific Gyre

    Science.gov (United States)

    Shimono, Takaya; Yamazaki, Toshitsugu

    2016-04-01

    Nonfossiliferous red clay can be used for elucidating long-range environmental changes, although such studies were limited so far because of the difficulty in precise age estimation and extremely low sedimentation rates. We conducted an environmental rock-magnetic study of Cenozoic red clay at the Integrated Ocean Drilling Program Site U1365 in the South Pacific Gyre. Magnetostratigraphy could be established only above ˜6 m below the seafloor (mbsf) (˜5 Ma). Below ˜6 mbsf, the ages of the cores were transferred from the published ages of nearby Deep Sea Drilling Project Site 596, which is based mainly on a constant Cobalt flux model, by intercore correlation using magnetic susceptibility and rare earth element content variation patterns. Rock-magnetic analyses including first-order reversal curve diagrams, the ratio of anhysteretic remanent magnetization susceptibility to saturation isothermal remanent magnetization (SIRM), and IRM component analyses revealed that magnetic minerals consist mainly of biogenic magnetite and terrigenous maghemite, and that the proportion of the terrigenous component increased since ˜23 Ma. We consider that the increase reflects a growth of eolian dust flux associated with a northward shift of Australia and the site to an arid region of the middle latitudes. The increase of the terrigenous component accelerated after ˜5 Ma, which may be associated with a further growth of the Antarctic glaciation at that time. This is coeval with the onset of the preservation of magnetostratigraphy, suggesting that the primary remanent magnetization is carried by the terrigenous component.

  6. Temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the Hakuho Maru in the North Pacific Ocean and South Pacific Ocean from 1991-09-17 to 1991-10-02 (NODC Accession 0115596)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115596 includes chemical, discrete sample, physical and profile data collected from Hakuho Maru in the North Pacific Ocean and South Pacific Ocean...

  7. Dissolved inorganic carbon, pH, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the MIRAI in the North Pacific Ocean and South Pacific Ocean from 2002-12-17 to 2003-02-14 (NODC Accession 0113608)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0113608 includes chemical, discrete sample, physical and profile data collected from MIRAI in the North Pacific Ocean and South Pacific Ocean from...

  8. Partial pressure (or fugacity) of carbon dioxide, dissolved inorganic carbon, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the KNORR in the North Pacific Ocean and South Pacific Ocean from 1992-10-06 to 1993-04-13 (NODC Accession 0115156)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115156 includes chemical, discrete sample, physical and profile data collected from KNORR in the North Pacific Ocean and South Pacific Ocean from...

  9. Temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the Hakuho Maru in the North Pacific Ocean and South Pacific Ocean from 1991-08-13 to 1991-09-01 (NODC Accession 0115591)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115591 includes chemical, discrete sample, physical and profile data collected from Hakuho Maru in the North Pacific Ocean and South Pacific Ocean...

  10. Dissolved inorganic carbon, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the Kaiyo in the North Pacific Ocean and South Pacific Ocean from 1994-01-06 to 1994-02-05 (NODC Accession 0112362)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112362 includes chemical, discrete sample, physical and profile data collected from Kaiyo in the North Pacific Ocean and South Pacific Ocean from...

  11. Partial pressure (or fugacity) of carbon dioxide, dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from NOAA Ship RONALD H. BROWN in the North Pacific Ocean, South Pacific Ocean and Southern Oceans from 2007-12-15 to 2008-02-23 (NODC Accession 0109903)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0109903 includes discrete sample and profile data collected from NOAA Ship RONALD H. BROWN in the North Pacific Ocean, South Pacific Ocean and...

  12. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from WECOMA and GYRE in the North Pacific Ocean and South Pacific Ocean from 1979-02-07 to 1980-06-14 (NCEI Accession 0143951)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0143951 includes discrete sample and profile data collected from WECOMA and GYRE in the North Pacific Ocean and South Pacific Ocean from 1979-02-07 to...

  13. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from Surface underway, discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from MIRAI in the Bering Sea, North Pacific Ocean and South Pacific Ocean from 2007-10-08 to 2007-12-26 (NODC Accession 0108123)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0108123 includes Surface underway, discrete sample and profile data collected from MIRAI in the Bering Sea, North Pacific Ocean and South Pacific...

  14. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from SOUTHERN SURVEYOR in the North Pacific Ocean and South Pacific Ocean from 2009-02-03 to 2009-03-24 (NODC Accession 0108082)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0108082 includes chemical, discrete sample, physical and profile data collected from SOUTHERN SURVEYOR in the North Pacific Ocean and South Pacific...

  15. Dissolved inorganic carbon, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the Kaiyo in the North Pacific Ocean and South Pacific Ocean from 1997-11-29 to 1997-12-25 (NODC Accession 0112363)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112363 includes chemical, discrete sample, physical and profile data collected from Kaiyo in the North Pacific Ocean and South Pacific Ocean from...

  16. Dissolved inorganic carbon, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the MIRAI in the North Pacific Ocean and South Pacific Ocean from 1999-10-13 to 1999-11-20 (NODC Accession 0112253)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112253 includes chemical, discrete sample, physical and profile data collected from MIRAI in the North Pacific Ocean and South Pacific Ocean from...

  17. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the THOMAS WASHINGTON in the North Pacific Ocean and South Pacific Ocean from 1991-08-31 to 1991-10-01 (NODC Accession 0115174)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115174 includes chemical, discrete sample, physical and profile data collected from THOMAS WASHINGTON in the North Pacific Ocean and South Pacific...

  18. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the MIRAI in the North Pacific Ocean and South Pacific Ocean from 2004-11-17 to 2004-12-09 (NODC Accession 0112263)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112263 includes chemical, discrete sample, physical and profile data collected from MIRAI in the North Pacific Ocean and South Pacific Ocean from...

  19. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from NOAA Ship DISCOVERER in the North Pacific Ocean and South Pacific Ocean from 1992-09-06 to 1992-12-08 (NODC Accession 0000193)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0000193 includes chemical, discrete sample, physical and profile data collected from NOAA Ship DISCOVERER in the North Pacific Ocean and South Pacific...

  20. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer and other instruments from L'ATALANTE in the North Pacific Ocean and South Pacific Ocean from 1994-09-23 to 1994-10-30 (NCEI Accession 0157463)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157463 includes Surface underway, chemical, meteorological and physical data collected from L'ATALANTE in the North Pacific Ocean and South Pacific...

  1. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer and other instruments from L'ATALANTE in the North Pacific Ocean and South Pacific Ocean from 1994-11-05 to 1994-11-29 (NCEI Accession 0157470)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157470 includes Surface underway, chemical, meteorological and physical data collected from L'ATALANTE in the North Pacific Ocean and South Pacific...

  2. Dissolved inorganic carbon, pH, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the MIRAI in the North Pacific Ocean and South Pacific Ocean from 2000-12-27 to 2001-02-08 (NODC Accession 0112353)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112353 includes biological, chemical, discrete sample, physical and profile data collected from MIRAI in the North Pacific Ocean and South Pacific...

  3. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the MIRAI in the North Pacific Ocean and South Pacific Ocean from 2007-02-16 to 2007-03-26 (NODC Accession 0112269)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112269 includes chemical, discrete sample, physical and profile data collected from MIRAI in the North Pacific Ocean and South Pacific Ocean from...

  4. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Barometric pressure sensor, Carbon dioxide (CO2) gas analyzer and other instruments from Investigator in the North Pacific Ocean, South Pacific Ocean and Southern Oceans from 2016-04-26 to 2016-06-29 (NCEI Accession 0160555)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0160555 includes Surface underway, chemical, meteorological and physical data collected from Investigator in the North Pacific Ocean, South Pacific...

  5. Partial pressure (or fugacity) of carbon dioxide, dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from NOAA Ship DISCOVERER in the North Pacific Ocean, South Pacific Ocean and Southern Oceans from 1994-01-26 to 1994-04-27 (NODC Accession 0115152)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0115152 includes chemical, discrete sample, physical and profile data collected from NOAA Ship DISCOVERER in the North Pacific Ocean, South Pacific...

  6. Measurement of dark, particle-generated superoxide and hydrogen peroxide production and decay in the subtropical and temperate North Pacific Ocean

    Science.gov (United States)

    Roe, Kelly L.; Schneider, Robin J.; Hansel, Colleen M.; Voelker, Bettina M.

    2016-01-01

    chemiluminescence detection, using dark incubations of unfiltered water samples to simultaneously determine production and decay rates. H2O2 concentrations at Station ALOHA ranged from 7 to 88 nM. Dark production rates and decay rate coefficients were low (mostly <1.5 nM hr-1 and <0.03 h-1, respectively); higher values were detected when biota were pre-concentrated with net tows. These rates of ROS production are lower than those reported by previous studies in other regions of the Pacific Ocean, but could still be significant compared to photochemical production.

  7. Relationships between sea surface temperature anomalies in the Pacific and Atlantic Oceans and South Texas precipitation and streamflow variability

    Science.gov (United States)

    Murgulet, Dorina; Valeriu, Murgulet; Hay, Richard R.; Tissot, Philippe; Mestas-Nuñez, Alberto M.

    2017-07-01

    While many studies have described linkages between large-scale climate phenomena and precipitation and streamflow, fewer studies explicitly address the climatic modulations at sub-regional scales. This study quantifies statistically the temporal variability in precipitation and streamflow at a regional scale in the semi-arid area of South Texas associated with three climate indices: El Niño-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and Atlantic Multidecadal Oscillation (AMO). Results show that ENSO and PDO strongly modulate rainfall during the cold season and, to various extents, streamflow during the cold and warm seasons. In addition, this study shows that in South Texas streamflow is consistently below normal (i.e. means) while precipitation slightly increases during AMO-warm. To different extents, the Pacific and Atlantic sea surface temperature (SST) anomalies show stronger influences on the climate of South Texas when coupled. Droughts are more correlated with La Niña events but these events play a secondary role during PDO-cold. Although the PDO-cold phase is the dominant driver of droughts in this area, our analyses also show that the coupled effect of the PDO-cold/AMO-warm phases significantly increases the intensity of drought conditions to a degree similar to the PDO-cold/La Niña coupled effect. Given its stronger response to climate anomalies, streamflow offers a more effective tool for predicting climate variability impacts on South Texas water resources when compared to precipitation.

  8. Imaging the Sub-Tropical Front off the southeast coast of New Zealand's South Island using high-frequency seismic methods

    Science.gov (United States)

    Gorman, A. R.; Bowman, M. H.

    2010-12-01

    The Sub-Tropical Front off the SE coast of New Zealand is an enigmatic ocean boundary that separates sub-tropical waters that are generally warm, low in nutrients, and sustain high levels of phytoplankton growth (primary productivity) from sub-antarctic waters that are generally cold, high in nutrients, and low in productivity. This region regularly exhibits evidence of nutrient transport across the Sub-Tropical Front that suggests significant ocean mixing across the front resulting in the transfer of iron from sub-tropical to sub-antarctic waters. Conventional ship-based oceanographic methods are incapable of observing these processes due to their sporadic and spatially-constrained nature. Seismic oceanographic methods have been shown to provide a means to image water body interactions such as these. However, a significant deficiency in current seismic oceanography imaging (i.e., using standard airgun profiles) is a failure to image the upper ~150 m of the ocean. This is due to: (1) the masking of shallow reflections by high-amplitude direct arrivals, and (2) the relatively large setback of the first receivers (typically ~200 m), which restricts shallow reflections to large angles of incidence. High-resolution profiling methods, usually used for shallow sub-bottom profiling, address both of these points, given (1) the low energy level of the sources and (2) the close proximity of the hydrophones. In addition to being a new technique for imaging the water column, such methods (with frequency characteristics that cover a large range of possible targets) have the potential to fill in a critical gap in existing seismic oceanography techniques. These methods also are much less expensive (at least over some depth ranges) than conventional methods that use large dedicated seismic vessels. We present first results from a 55-km-long coast-perpendicular transect across the Sub-Tropical Front off the SE coast of New Zealand. The transect is divided into seven segments by

  9. Inferring wavelength dependence of AOD and Ångström exponent over a sub-tropical station in South Africa using AERONET data: influence of meteorology, long-range transport and curvature effect.

    Science.gov (United States)

    Kumar, K Raghavendra; Sivakumar, V; Reddy, R R; Gopal, K Rama; Adesina, A Joseph

    2013-09-01

    Aerosol optical properties over a southern sub-tropical site Skukuza, South Africa were studied to determine the variability of the aerosol characteristics using CIMEL Sunphotometer data as part of the AErosol RObotic NETwork (AERONET) from December 2005 to November 2006. Aerosol optical depth (AOD), Ångström exponent (α), and columnar water vapor (CWV) data were collected, analyzed, and compiled. Participating in this network provided a unique opportunity for understanding the sources of aerosols affecting the atmosphere of South Africa (SA) and the regional radiation budget. The meteorological patterns significantly (p1 μm). Trajectory cluster analyses revealed that the air masses during the autumn and winter seasons have longer advection pathways, passing over the ocean and continent. This is reflected in the aerosol properties that are derived from the ocean, desert, and anthropogenic activities that include biomass burning and industrial pollution. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. High NDVI and Potential Canopy Photosynthesis of South American Subtropical Forests despite Seasonal Changes in Leaf Area Index and Air Temperature

    Directory of Open Access Journals (Sweden)

    Piedad M. Cristiano

    2014-02-01

    Full Text Available The canopy photosynthesis and carbon balance of the subtropical forests are not well studied compared to temperate and tropical forest ecosystems. The main objective of this study was to assess the seasonal dynamics of Normalized Difference Vegetation Index (NDVI and potential canopy photosynthesis in relation to seasonal changes in leaf area index (LAI, chlorophyll concentration, and air temperatures of NE Argentina subtropical forests throughout the year. We included in the analysis several tree plantations (Pinus, Eucalyptus and Araucaria species that are known to have high productivity. Field studies in native forests and tree plantations were conducted; stem growth rates, LAI and leaf chlorophyll concentration were measured. MODIS satellite-derived LAI (1 km SIN Grid and NDVI (250m SIN Grid from February 2000 to 2012 were used as a proxy of seasonal dynamics of potential photosynthetic activity at the stand level. The remote sensing LAI of the subtropical forests decreased every year from 6 to 5 during the cold season, similar to field LAI measurements, when temperatures were 10 °C lower than during the summer. The yearly maximum NDVI values were observed during a few months in autumn and spring (March through May and November, respectively because high and low air temperatures may have a small detrimental effect on photosynthetic activity during both the warm and the cold seasons. Leaf chlorophyll concentration was higher during the cold season than the warm season which may have a compensatory effect on the seasonal variation of the NDVI values. The NDVI of the subtropical forest stands remained high and fairly constant throughout the year (the intra-annual coefficient of variation was 1.9%, and were comparable to the values of high-yield tree plantations. These results suggest that the humid subtropical forests in NE Argentina potentially could maintain high canopy photosynthetic activity throughout the year and thus this ecosystem may

  11. A proposed time transfer experiment between the USA and the South Pacific

    Science.gov (United States)

    Luck, John; Dunkley, John; Armstrong, Tim; Gifford, Guy A.; Landis, Paul; Rasmussen, Scott; Wheeler, Paul J.; Bartholomew, Thomas R.; Stein, Samuel R.

    1992-07-01

    Described here are the concept, architecture and preliminary details of an experiment directed towards providing continuous Ultra High Precision (UHP) time transfer between Washington, DC; Salisbury, SA Australia; Orroral Valley, ACT Australia; and Lower Hutt, New Zealand. A proposed method of distributing UTC(USNO) at a high level of precision to passive users over a broad area of the South Pacific is described. The concept is based on active two-way satellite time transfer from the United States Naval Observatory (USNO) to the proposed USNO Master Clock West (MCW) in Wahiwa, HI at the 1 nanosecond level using active satellite two-way time transfer augmented by Precise Positioning Service (PPS) of the Global Positioning System (GPS). MCW would act as an intermediate transfer/reference station, again linked to Salisbury at the 1 nanosecond level using active satellite two-way time transfer augmented by PPS GPS. From this point, time would be distributed within the region by two methods. The first is an existing TV line sync system using an Australian communications satellite (AUSSAT K1) which is useful to the 20 nanosecond level. The second approach is RF ranging and multilateration between Salisbury, Orroral Observatory, Lower Hutt and the AUSSAT B1 and B2 to be launched in 1992. Orroral Observatory will provide precise laser ranging to the AUSSAT B1/B2 retro reflectors which will reduce ephemeris related time transfer errors to below 1 nanosecond. The corrected position will be transmitted by both the time transfer modem and the existing TV line sync dissemination process. Multilateration has the advantage of being an all weather approach and when used with the laser ranging technique will provide a precise measurement of the propagation path delays. This will result in time transfer performance levels on the order of 10 nanoseconds to passive users in both Australia and New Zealand.

  12. Biochemical characteristics and bacterial community structure of the sea surface microlayer in the South Pacific Ocean

    Directory of Open Access Journals (Sweden)

    I. Obernosterer

    2008-05-01

    Full Text Available The chemical and biological characteristics of the surface microlayer were determined during a transect across the South Pacific Ocean in October-December 2004. Concentrations of particulate organic carbon (1.3 to 7.6-fold and nitrogen (1.4 to 7-fold, and POC:PON ratios were consistently higher in the surface microlayer as compared to surface waters (5 m. The large variability in particulate organic matter enrichment was negatively correlated to wind speed. No enhanced concentrations of dissolved organic carbon were detectable in the surface microlayer as compared to 5 m, but chromophoric dissolved organic matter was markedly enriched (by 2 to 4-fold at all sites. Based on pigment analysis and cell counts, no consistent enrichment of any of the major components of the autotrophic and heterotrophic microbial community was detectable. CE-SSCP fingerprints and CARD FISH revealed that the bacterial communities present in the surface microlayer had close similarity (>76% to those in surface waters. By contrast, bacterial heterotrophic production (3H-leucine incorporation was consistently lower in the surface microlayer than in surface waters. By applying CARD-FISH and microautoradiography, we observed that Bacteroidetes and Gammaproteobacteria dominated leucine uptake in the surface microlayer, while in surface waters Bacteroidetes and Alphaproteobacteria were the major groups accounting for leucine incorporation. Our results demonstrate that the microbial community in the surface microlayer closely resembles that of the surface waters of the open ocean. Even a short residence in the surface microlayer influences leucine incorporation by different bacterial groups, probably as a response to the differences in the physical and chemical nature of the two layers.

  13. Dust, Volcanic Ash, and the Evolution of the South Pacific Gyre through the Cenozoic

    Science.gov (United States)

    Dunlea, A. G.; Murray, R. W.; Sauvage, J.; Spivack, A. J.; Harris, R. N.; D'Hondt, S.; Higgins, J. A.

    2015-12-01

    Dust and volcanic ash play a critical role in past global climate by affecting cloud cover and ocean nutrients as well as responding to changes in tectonics, aridity, and wind. Because the eolian fluxes in the Southern Hemisphere are so low, subtle changes in the absolute flux of dust and volcanic ash may have a disproportionally large impact on climate. Our multi-site record of eolian dust and volcanic ash accumulation in pelagic clay of the South Pacific Gyre (SPG), gathered during IODP Expedition 329, shows that eolian fluxes varied by an order of magnitude over the Cenozoic and correlate with changes of tectonic processes and global climate. We analyzed the concentrations of 37 elements in 138 bulk pelagic clay samples from 6 sites drilled throughout the SPG. Using multivariate statistical modeling of the geochemical dataset (e.g. Q-mode factor analysis and multiple linear regression) and a cobalt-based age model, we quantified the mass accumulation rate (MAR) of 6 end-members that comprise the SPG pelagic clay: dust, rhyolite, altered basalt, Fe-Mn oxyhydroxides, excess Si, and apatite. Our record shows that Australian dust MAR begins at the Early Eocene Climatic Optimum ~50 Ma as global temperatures began to cool and Australia began to tectonically separate from Antarctica. The mid-Miocene has noticeably higher MAR of dust and ash at multiple sites. While a simultaneous increase in production is possible (i.e., more aridity and volcanic activity), the synchronicity may be more indicative of stronger winds in the Southern Hemisphere and increased material in the atmosphere during this time. Heavier Mg isotopes occur at Site U1366 in samples that are composed primarily of hydrothermal deposition, excess Si, and volcanic ash. The Mg isotopic enrichment suggests that these components have undergone alterations to form authigenic aluminosilicates.

  14. An algorithm for detecting Trichodesmium surface blooms in the South Western Tropical Pacific

    Directory of Open Access Journals (Sweden)

    Y. Dandonneau

    2011-12-01

    Full Text Available Trichodesmium, a major colonial cyanobacterial nitrogen fixer, forms large blooms in NO3-depleted tropical oceans and enhances CO2 sequestration by the ocean due to its ability to fix dissolved dinitrogen. Thus, its importance in C and N cycles requires better estimates of its distribution at basin to global scales. However, existing algorithms to detect them from satellite have not yet been successful in the South Western Tropical Pacific (SP. Here, a novel algorithm (TRICHOdesmium SATellite based on radiance anomaly spectra (RAS observed in SeaWiFS imagery, is used to detect Trichodesmium during the austral summertime in the SP (5° S–25° S 160° E–170° W. Selected pixels are characterized by a restricted range of parameters quantifying RAS spectra (e.g. slope, intercept, curvature. The fraction of valid (non-cloudy pixels identified as Trichodesmium surface blooms in the region is low (between 0.01 and 0.2 %, but is about 100 times higher than deduced from previous algorithms. At daily scales in the SP, this fraction represents a total ocean surface area varying from 16 to 48 km2 in Winter and from 200 to 1000 km2 in Summer (and at monthly scale, from 500 to 1000 km2 in Winter and from 3100 to 10 890 km2 in Summer with a maximum of 26 432 km2 in January 1999. The daily distribution of Trichodesmium surface accumulations in the SP detected by TRICHOSAT is presented for the period 1998–2010 which demonstrates that the number of selected pixels peaks in November–February each year, consistent with field observations. This approach was validated with in situ observations of Trichodesmium surface accumulations in the Melanesian archipelago around New Caledonia, Vanuatu and Fiji Islands for the same period.

  15. Aphotic N2 fixation in the Eastern Tropical South Pacific Ocean.

    Directory of Open Access Journals (Sweden)

    Sophie Bonnet

    Full Text Available We examined rates of N2 fixation from the surface to 2000 m depth in the Eastern Tropical South Pacific (ETSP during El Niño (2010 and La Niña (2011. Replicated vertical profiles performed under oxygen-free conditions show that N2 fixation takes place both in euphotic and aphotic waters, with rates reaching 155 to 509 µmol N m(-2 d(-1 in 2010 and 24±14 to 118±87 µmol N m(-2 d(-1 in 2011. In the aphotic layers, volumetric N2 fixation rates were relatively low (<1.00 nmol N L(-1 d(-1, but when integrated over the whole aphotic layer, they accounted for 87-90% of total rates (euphotic+aphotic for the two cruises. Phylogenetic studies performed in microcosms experiments confirm the presence of diazotrophs in the deep waters of the Oxygen Minimum Zone (OMZ, which were comprised of non-cyanobacterial diazotrophs affiliated with nifH clusters 1K (predominantly comprised of α-proteobacteria, 1G (predominantly comprised of γ-proteobacteria, and 3 (sulfate reducing genera of the δ-proteobacteria and Clostridium spp., Vibrio spp.. Organic and inorganic nutrient addition bioassays revealed that amino acids significantly stimulated N2 fixation in the core of the OMZ at all stations tested and as did simple carbohydrates at stations located nearest the coast of Peru/Chile. The episodic supply of these substrates from upper layers are hypothesized to explain the observed variability of N2 fixation in the ETSP.

  16. Size-resolved sulfate and ammonium measurements in marine boundary layer over the North and South Pacific

    OpenAIRE

    Ooki, Atsushi; Uematsu, Mitsuo; NORIKI, Shinichiro

    2007-01-01

    Marine background levels of non-sea-salt- (nss-) SO42− (5.0–9.7 neq m−3), NH4+ (2.1–4.4 neq m−3) and elemental carbon (EC) (40–80 ngC m−3) in aerosol samples were measured over the equatorial and South Pacific during a cruise by the R/V Hakuho-maru from November 2001 to March 2002. High concentrations of nss-SO42− (47–94 neq m−3), NH4+ (35–94 neq m−3) and EC (130–460 ngC m−3) were found in the western North Pacific near the coast of the Asian continent under the influence of the Asian winter ...

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

    Science.gov (United States)

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

    2017-10-01

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

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

    Science.gov (United States)

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

    2018-02-01

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

  19. Immunohistochemical localization of CYP1A, vitellogenin and Zona radiata proteins in the liver of swordfish (Xiphias gladius L.) taken from the Mediterranean Sea, South Atlantic, South Western Indian and Central North Pacific Oceans.

    Science.gov (United States)

    Desantis, S; Corriero, A; Cirillo, F; Deflorio, M; Brill, R; Griffiths, M; Lopata, A L; de la Serna, J M; Bridges, C R; Kime, D E; De Metrio, G

    2005-01-18

    Cytochrome P4501A (CYP1A) monoxygenase, vitellogenin (Vtg) and Zona radiata proteins (Zrp) are frequently used as biomarkers of fish exposure to organic contaminants. In this work, swordfish liver sections obtained from the Mediterranean Sea, the South African coasts (South Atlantic and South Western Indian Oceans) and the Central North Pacific Ocean were immunostained with antisera against CYP1A, Zrp, and Vtg. CYP1A induction was found in hepatocytes, epithelium of the biliary ductus and the endothelium of large blood vessels of fish from the Mediterranean Sea and South African waters, but not from the Pacific Ocean. Zrp and Vtg were immunolocalized in hepatocytes of male swordfish from the Mediterranean Sea and from South African waters. Plasma Dot-Blot analysis, performed in Mediterranean and Pacific specimens, revealed the presence of Zrp and Vtg in males from Mediterranean but not from Pacific. These results confirm previous findings about the potential exposure of Mediterranean swordfish to endocrine, disrupting chemicals and raise questions concerning the possible presence of xenobiotic contaminants off the Southern coasts of South Africa in both the South Atlantic and South Western Indian Oceans.

  20. Advances in Knowledge Discovery and Data Mining 21st Pacific Asia Conference, PAKDD 2017 Held in Jeju, South Korea, May 23 26, 2017. Proceedings Part I, Part II.

    Science.gov (United States)

    2017-06-27

    currently val!d OMB control number. PLEASE DD NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) 2. REPORT TYPE 3. DATES COVERED...Data Mining 21’’ Pacific-Asia Conference, PAKDD 2017Jeju, South Korea, May 23-26, Sb. GRANT NUMBER 2017 Proceedings, Part I, Part II Sc. PROGRAM...Springer; Switzerland. 14. ABSTRACT The Pacific-Asia Conference on Knowledge Discovery and Data Mining (PAKDD) is a leading international conference

  1. The Effect of ENSO on Phytoplankton Composition in the Pacific Ocean

    Science.gov (United States)

    Rousseaux, Cecile

    2012-01-01

    The effect of climate variability on phytoplankton communities was assessed for the tropical and sub-tropical Pacific Ocean between 1998 and 2005 using an established biogeochemical assimilation model. The phytoplankton communities exhibited wide range of responses to climate variability, from radical shifts in the Equatorial Pacific, to changes of only a couple of phytoplankton groups in the North Central Pacific, to no significant changes in the South Pacific. In the Equatorial Pacific, climate variability dominated the variability of phytoplankton. Here, nitrate, chlorophyll and all but one of the 4 phytoplankton types (diatoms, cyanobacteria and coccolithophores) were strongly correlated (p less than 0.01) with the Multivariate El Nino Southern Oscillation Index (MEI). In the North Central Pacific, MEI and chlorophyll were significantly (pphytoplankton groups (chlorophytes and coccolithophores). Ocean biology in the South Pacific was not significantly correlated with MEI. During La Ni a events, diatoms increased and expanded westward along the cold tongue (correlation with MEI, r=-0.81), while cyanobacteria concentrations decreased significantly (r=0.78). El Nino produced the reverse pattern, with cyanobacteria populations increasing while diatoms plummeted. The diverse response of phytoplankton in the different major basins of the Pacific suggests the different roles climate variability can play in ocean biology.

  2. Radiolyis and life in deep subseafloor sediment of the South Pacific Gyre

    Science.gov (United States)

    Sauvage, J.; Spivack, A. J.; Dunlea, A. G.; Murray, R. W.; Smith, D. C.; D'Hondt, S. L.

    2012-12-01

    Integrated Ocean Drilling Program Expedition 329 revealed the occurrence of a fundamentally different subsurface world below the South Pacific Gyre (SPG) compared to previously drilled sites. The organic-poor sediment that underlies this vast ultra-oligotrophic region harbors microbial communities characterized by cell abundances three to four orders of magnitude lower than has been found at similar depths outside the gyre. The sediment column is oxic and rich in major nutrients from the seafloor to beneath the sediment-basement interface. Statistical analysis of the dissolved O2 profiles for the six sites within the SPG (U1365 through U1370) demonstrates that measurable organic-fuelled O2 reduction is limited to the upper meters of SPG sediment. At greater depths, maximum mean organic-fueled respiration rates range from 10-5 to 10-3 fmol O2 cell-1 day-1, representing a tremendously low cellular metabolism. Hydrogen is continuously produced in this sedimentary environment by radioactive splitting of water, a process known as water radiolysis. However, measured dissolved hydrogen abundances are below detection in most samples at all six sites. This combination of continuous production and low concentration suggests that radiolytic hydrogen may be a biological electron donor in the organic-poor sediment of the SPG. Gibbs energy of reaction calculations for the knallgas reaction (H2 + ½ O2 = H2O) and other hydrogen-consuming reactions show that where hydrogen concentration is above detection in SPG sediment, hydrogen oxidation is energetically favorable for microbial life (in-situ ΔGreaction averaging -210, -190, and -12 kJ/mol H2 throughout the sequence for oxygen, nitrate and sulfate reduction, respectively). By applying the water radiolysis model of Blair et al. (2007) to our preliminary data from Site U1366, we presently estimate that on average 10-5 fmol radiolytic H2 cell-1 day-1 is available throughout the site's sediment column. By measuring the radioactive

  3. New host and distributional records for Cryptosporidium sp. (Apicomplexa: Cryptosporidiidae) from lizards (Sauria: Gekkonidae, Scincidae) from the Cook Islands and Vanuatu, South Pacific

    Science.gov (United States)

    McAllister, Chris T.; Duszynski, Donald W.; Fisher, Robert N.

    2013-01-01

    Between 1991 and 1993, 295 lizards, comprising 21 species in 2 families (Gekkonidae, Scincidae) from the Cook Islands, Fiji, Palau, Takapoto, and Vanuatu in the South Pacific, were examined for Cryptosporidium oocysts. Only 6 lizards (2%) were found to be passing Cryptosporidium oocysts in their feces, including 2 of 30 (7%) Oceania geckos, Gehyra oceanica, from Rarotonga, Cook Islands, and 4 of 26 (15%) Pacific blue-tailed skinks, Emoia caeruleocauda, from Efate Island, Vanuatu. This represents the largest survey for Cryptosporidium in Pacific island lizards, and we document 2 new host and 2 new locality records for this parasite genus.

  4. Physical and biogeochemical forcing of oxygen and nitrate changes during El Niño/El Viejo and La Niña/La Vieja upper-ocean phases in the tropical eastern South Pacific along 86° W

    Directory of Open Access Journals (Sweden)

    P. J. Llanillo

    2013-10-01

    Full Text Available Temporal changes in the water mass distribution and biogeochemical signals in the tropical eastern South Pacific are investigated with the help of an extended optimum multi-parameter (OMP analysis, a technique for inverse modeling of mixing and biogeochemical processes through a multidimensional least-square fit. Two ship occupations of a meridional section along 85°50' W from 14° S to 1° N are analysed during relatively warm (El Niño/El Viejo, March 1993 and cold (La Niña/La Vieja, February 2009 upper-ocean phases. The largest El Niño–Southern Oscillation (ENSO impact was found in the water properties and water mass distribution in the upper 200 m north of 10° S. ENSO promotes the vertical motion of the oxygen minimum zone (OMZ associated with the hypoxic equatorial subsurface water (ESSW. During a cold phase the core of the ESSW is found at shallower layers, replacing shallow (top 200 m subtropical surface water (STW. The heave of isopycnals due to ENSO partially explains the intrusion of oxygen-rich and nutrient-poor antarctic intermediate water (AAIW into the depth range of 150–500 m. The other cause of the AAIW increase at shallower depths is that this water mass flowed along shallower isopycnals in 2009. The shift in the vertical location of AAIW reaching the OMZ induces changes in the amount of oxygen advected and respired inside the OMZ: the larger the oxygen supply, the greater the respiration and the lower the nitrate loss through denitrification. Variations in the intensity of the zonal currents in the equatorial current system, which ventilates the OMZ from the west, are used to explain the patchy latitudinal changes of seawater properties observed along the repeated section. Significant changes reach down to 800 m, suggesting that decadal variability (Pacific decadal oscillation is also a potential driver in the observed variability.

  5. Hematozoa of forest birds in American Samoa - Evidence for a diverse, indigenous parasite fauna from the South Pacific

    Science.gov (United States)

    Atkinson, C.T.; Utzurrum, R.C.; Seamon, J.O.; Savage, Amy F.; Lapointe, D.A.

    2006-01-01

    Introduced avian diseases pose a significant threat to forest birds on isolated island archipelagos, especially where most passerines are endemic and many groups of blood-sucking arthropods are either absent or only recently introduced. We conducted a blood parasite survey of forest birds from the main islands of American Samoa to obtain baseline information about the identity, distribution and prevalence of hematozoan parasites in this island group. We examined Giemsa-stained blood smears from 857 individual birds representing 20 species on Tutuila, Ofu, Olosega, and Ta'u islands. Four hematozoan parasites were identified - Plasmodium circumflexum (1%, 12/857), Trypanosoma avium (4%, 32/857), microfilaria (9%, 76/857), and an Atoxoplasma sp. (parasite infections. Given the central location of American Samoa in the South Pacific, it is likely that avian malaria and other hematozoan parasites are indigenous and widespread at least as far as the central South Pacific. Their natural occurrence may provide some immunological protection to indigenous birds in the event that other closely related parasites are accidentally introduced to the region.

  6. Opiine parasitoids (Hymenoptera: Braconidae) of tropical fruit flies (Diptera: Tephritidae) of the Australian and South Pacific region.

    Science.gov (United States)

    Carmichael, A E; Wharton, R A; Clarke, A R

    2005-12-01

    Opiine wasps are parasitoids of dacine fruit flies, the primary horticultural pests of Australia and the South Pacific. A taxonomic synopsis and distribution and host records (44% of which are new) for each of the 15 species of dacine-parasitizing opiine braconids found in the South Pacific is presented. Species dealt with are Diachasmimorpha hageni (Fullaway), D. kraussii (Fullaway), D. longicaudata (Ashmead), D. tryoni (Cameron), Fopius arisanus (Sonan), F. deeralensis (Fullaway), F. ferrari Carmichael & Wharton sp. n., F. illusorius (Fischer) comb. n., F. schlingeri Wharton, Opius froggatti Fullaway, Psyttalia fijiensis (Fullaway), P. muesebecki (Fischer), P. novaguineensis (Szépligeti) and Utetes perkinsi (Fullaway). A potentially undescribed species, which may be a colour morph of F. vandenboschi (Fullaway), is diagnosed but not formally described. Fopius vandenboschi sensu stricto, Diachasmimorpha fullawayi Silvestri, Psyttalia concolor Szépligeti and P. incisi Silvestri have been liberated into the region but are not considered to have established: a brief diagnosis of each is included. Biosteres illusorius Fischer is formally transferred to the genus Fopius. A single opiine specimen reared from a species of Bactrocera (Bulladacus) appears to be Utetes albimanus (Szépligeti), but damage to this specimen and to the holotype (the only previously known specimen) means that this species remains unconfirmed as a fruit fly parasite: a diagnosis of U. cf. albimanus is provided. Psyttalia novaguineensis could not be adequately separated from P. fijiensis using previously published characterizations and further work to resolve this complex is recommended. A key is provided to all taxa.

  7. Relationship of the South Asian Monsoon and Regional Drought with Distinct Equatorial Pacific SST Patterns on Interannual and Decadal Timescales

    Science.gov (United States)

    Hernandez, M.; Ummenhofer, C.; Anchukaitis, K. J.

    2014-12-01

    The Asian monsoon system influences the lives of over 60% of the planet's population, with widespread socioeconomic effects resulting from weakening or failure of monsoon rains. Spatially broad and temporally extended drought episodes have been known to dramatically influence human history, including the Strange Parallels Drought in the mid-18th century. Here, we explore the dynamics of sustained monsoon failure using the Monsoon Asia Drought Atlas - a high-resolution network of hydro-climatically sensitive tree-ring records - and a 1300-year pre-industrial control run of the Community Earth System Model (CESM). Spatial drought patterns in the instrumental and model-based Palmer Drought Severity Index (PDSI) during years with extremely weakened South Asian monsoon are similar to those reconstructed during the Strange Parallels Drought in the MADA. We further explore how the large-scale Indo-Pacific climate during weakened South Asian monsoon differs between interannual and decadal timescales. The Strange Parallels Drought pattern is observed during March-April-May primarily over Southeast Asia, with decreased precipitation and reduced moisture fluxes, while anomalies in June-July-August are confined to the Indian subcontinent during both individual and decadal events. Individual years with anomalous drying exhibit canonical El Niño conditions over the eastern equatorial Pacific and associated shifts in the Walker circulation, while decadal events appear to be related to anomalous warming around the dateline in the equatorial Pacific, typical of El Niño Modoki events. The results suggest different dynamical processes influence drought at different time scales through distinct remote ocean influences.

  8. Response of the South Pacific Convergence Zone to imposed circulation and moisture perturbations in an intermediate level complexity model

    Science.gov (United States)

    Niznik, M. J.; Lintner, B. R.

    2014-12-01

    Previous research has identified a connection between the strength of low-level trade wind inflow from the relatively dry southeastern Pacific basin and the position of the South Pacific Convergence Zone (SPCZ). This circulation-precipitation relationship has been noted in composite analysis applied to reanalysis data as well as to output from current generation climate models, although the causality is ambiguous. Additionally, given that prior studies exhibit deep vertical structures associated with changes to low-level inflow east of the SPCZ, the relationship between low-level inflow variability and the propagation of upper level mid-latitude synoptic disturbances into the SPCZ remains unclear. Thus, forcing models with prescribed circulation and moisture anomalies may be instructive for untangling the dynamic and thermodynamic contributions to such interactions, as well as their potential causality. To that end, we use the Quasi-equilibrium Tropical Circulation Model 2 (QTCM2), an intermediate complexity model with a separate boundary layer of fixed height imposed at the base of the free troposphere, to explore the response of the SPCZ, and more broadly convection across the South Pacific, to perturbed low- and upper-level circulation and moisture fields east of its climatological position. Preliminary results suggest a strong precipitation response to strengthened low-level trade wind inflow, hypothesized to be the result of increased convergence in the climatological SPCZ, with an associated decrease in Intertropical Convergence Zone (ITCZ) precipitation. Conversely, there is a limited precipitation response to weakened low-level trade wind inflow despite a notable (2-3 g kg-1) increase in specific humidity, suggesting the climatological low-level inflow is already associated with the necessary moisture threshold for deep convection. Ultimately, these results suggest dynamics play a stronger role than thermodynamics in the interaction as modeled by QTCM2.

  9. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the North Pacific Ocean, South Atlantic Ocean and others from 2008-12-31 to 2009-12-22 (NCEI Accession 0144533)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144533 includes Surface underway data collected from LAURENCE M. GOULD in the North Pacific Ocean, South Atlantic Ocean, South Pacific Ocean and...

  10. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the North Pacific Ocean, South Atlantic Ocean and others from 2008-12-31 to 2009-12-21 (NCEI Accession 0148771)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0148771 includes Surface underway data collected from LAURENCE M. GOULD in the North Pacific Ocean, South Atlantic Ocean, South Pacific Ocean and...

  11. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the North Pacific Ocean, South Atlantic Ocean and others from 2004-12-31 to 2005-12-26 (NCEI Accession 0144531)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144531 includes Surface underway data collected from LAURENCE M. GOULD in the North Pacific Ocean, South Atlantic Ocean, South Pacific Ocean and...

  12. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the North Pacific Ocean, South Atlantic Ocean and others from 2004-12-30 to 2005-11-20 (NCEI Accession 0148772)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0148772 includes Surface underway data collected from LAURENCE M. GOULD in the North Pacific Ocean, South Atlantic Ocean, South Pacific Ocean and...

  13. Phytoplankton functional groups for ecological assessment in young sub-tropical reservoirs: case study of the Nam-Theun 2 Reservoir, Laos, South-East Asia

    Directory of Open Access Journals (Sweden)

    Joanna Martinet

    2014-05-01

    Full Text Available The early stages following the creation of reservoirs are typically physical and biological unstable periods due to the conversion from a lotic to a lentic ecosystem. The sub-tropical Nam Theun 2 Reservoir (Laos was impounded in 2008. Several limnological parameters were monitored from March 2009 to December 2011 in order to understand the evolution of the phytoplankton community. A strong inter annual variability of hydrodynamic pattern was observed. Rainfall and hydraulic balance were the main physical factors driving the community structure. Periods of highest hydraulic stability led to a phytoplankton biomasses increase. The first assemblages were dominated by the S-C-strategists reaching high biomasses but low diversity. Over the three years, phytoplankton became more diverse due to a diversification of ecological niches, mostly explained by a greater water transparency and a more stable thermal stratification. The applicability of functional groups for biomonitoring in this young sub-tropical reservoir was investigated and compared to a classical taxonomical approach. The dominant functional groups (Lo, A, E, F, N and P characterized the NT2 Reservoir as meso-oligotrophic with a tolerance to low nutrients supply. Our results support the hypothesis that a functional group approach is more informative than a species-based approach to assess trophic level and dissolved organic carbon concentrations in such reservoirs.

  14. South pacific climate variability and its impact on low-lying islands

    Directory of Open Access Journals (Sweden)

    1998-01-01

    Full Text Available VARIABILITE CLIMATIQUE DU SUD PACIFIQUE ET SES IMPACTS SUR LES ILES BASSES. L’environnement climatique du Pacifique sud est conditionné par “l’extrême océanité” de la région et l’interaction étroite entre l’atmosphère et l’océan qui conditionne la vie et l’ensemble des paramètres environnementaux des pays insulaires. Les deux principaux phénomènes climatiques qui affectent la région sont : ENSO ( El Niño - Southern Oscillation et le réchauffement global. Ces deux signaux climatiques, facteurs principaux de la variabilité climatique du Pacifique, font sentir leur action sur l’élévation du niveau moyen de l’océan qui, à terme, peut mettre en cause l’existence même de certains archipels, sur les modifications de la vie océanique et de son exploitation, sur la fréquence et l’intensité des cyclones, sur l’alternance des sécheresses et des périodes humides, sur la production agricole, et sur la santé des lagons et des formations récifales. VARIABILIDAD CLIMÁTICA EN EL PACÍFICO SUR Y SU IMPACTO EN ISLAS BAJAS. El medio ambiente climático de la región del Pacífico Sur se caracteriza por la interacción intensa del océano y la atmósfera, la cual impacta la vida y otros parámetros medioambientales de la región. Dos fenómenos principales están condicionando la variabilidad climática de la región: El Niño y la Oscilación del Sur (ENSO y el Calentamiento Global. Estos dos componentes del cambio climático están afectando la elevación del nivel del mar, la vida en el océano, la frecuencia e intensidad de los huracanes, la ocurrencia de sequías e inundaciones, la potencialidad agrícola, la salud de las regiones costeras incluyendo lagunas y arrecifes. The climatic environment of the South Pacific region is characterized by the intense ocean atmosphere interaction which impacts the life and other environmental parameters of the region. Two main phenomenons are conditioning the climate variability of

  15. South East Pacific atmospheric composition and variability sampled along 20° S during VOCALS-REx

    Directory of Open Access Journals (Sweden)

    G. Allen

    2011-06-01

    Full Text Available The VAMOS Ocean-Cloud-Atmosphere-Land Regional Experiment (VOCALS-REx was conducted from 15 October to 15 November 2008 in the South East Pacific (SEP region to investigate interactions between land, sea and atmosphere in this unique tropical eastern ocean environment and to improve the skill of global and regional models in representing the region. This study synthesises selected aircraft, ship and surface site observations from VOCALS-REx to statistically summarise and characterise the atmospheric composition and variability of the Marine Boundary Layer (MBL and Free Troposphere (FT along the 20° S parallel between 70° W and 85° W. Significant zonal gradients in mean MBL sub-micron aerosol particle size and composition, carbon monoxide, sulphur dioxide and ozone were seen over the campaign, with a generally more variable and polluted coastal environment and a less variable, more pristine remote maritime regime. Gradients in aerosol and trace gas concentrations were observed to be associated with strong gradients in cloud droplet number. The FT was often more polluted in terms of trace gases than the MBL in the mean; however increased variability in the FT composition suggests an episodic nature to elevated concentrations. This is consistent with a complex vertical interleaving of airmasses with diverse sources and hence pollutant concentrations as seen by generalised back trajectory analysis, which suggests contributions from both local and long-range sources. Furthermore, back trajectory analysis demonstrates that the observed zonal gradients both in the boundary layer and the free troposphere are characteristic of marked changes in airmass history with distance offshore – coastal boundary layer airmasses having been in recent contact with the local land surface and remote maritime airmasses having resided over ocean for in excess of ten days. Boundary layer composition to the east of 75° W was observed to be dominated by coastal

  16. Recognising indigenous peoples values and knowledge systems in Geoheritage: Case studies from New Zealand and the South Pacific.

    Science.gov (United States)

    Procter, Jonathan; Nemeth, Karoly

    2017-04-01

    Geological heritage or geoheritage focuses on the recognition and, to some extent, the protection of rocks, minerals, fossils, landforms, sediments, water and soils, and natural geomorphic processes that have some anthropomorphic value. These values are generally constrained by the geosite (sites of geological significance) having some scientific, educational, research and aesthetic significance. Criteria to determine the significance of a geosite are generally founded on conservation methodologies associated with ecology/biodiversity or the living components of the natural environment. These criteria presently focus on factors such as scale, scope and significance (from a scientific perspective). Very little value is attributed to the cultural connections of a geosite or the way a geosite has contributed to the development of a culture, its spirituality and understanding of the world. In the South Pacific, and in particular New Zealand, geosites and their related management (protection/conservation) mechanisms appear to be somewhat underutilized, possibly due to the fact that those mechanisms appear to the public as being initiatives related to the actions of the scientific community of which they may not consider themselves part. Indigenous communities of the South Pacific and New Zealand very rarely associate with the scientific community and view scientific methods as foreign to their own knowledge systems and worldviews. This generally results in conflict. In the South Pacific, the connection to volcanoes, volcanic landforms and features, and volcanic activity has been an important component to shaping various cultures over time. We present three case studies: (1) from Samoa that explores how important geosites are recorded through local knowledge repositories, (2) from the Auckland Volcanic Field where sites are being classified and protected with little recognition of indigenous peoples' values, and (3) from a UNESCO World Heritage Area that, while well

  17. Teleseismic P wave tomography of South Island, New Zealand upper mantle: Evidence of subduction of Pacific lithosphere since 45 Ma

    Science.gov (United States)

    Zietlow, Daniel W.; Molnar, Peter H.; Sheehan, Anne F.

    2016-06-01

    A P wave speed tomogram produced from teleseismic travel time measurements made on and offshore the South Island of New Zealand shows a nearly vertical zone with wave speeds that are 4.5% higher than the background average reaching to depths of approximately 450 km under the northwestern region of the island. This structure is consistent with oblique west-southwest subduction of Pacific lithosphere since about 45 Ma, when subduction beneath the region began. The high-speed zone reaches about 200-300 km below the depths of the deepest intermediate-depth earthquakes (subcrustal to ~200 km) and therefore suggests that ~200-300 km of slab below them is required to produce sufficient weight to induce the intermediate-depth seismicity. In the southwestern South Island, high P wave speeds indicate subduction of the Australian plate at the Puysegur Trench to approximately 200 km depth. A band with speeds ~2-3.5% lower than the background average is found along the east coast of the South Island to depths of ~150-200 km and underlies Miocene or younger volcanism; these low speeds are consistent with thinned lithosphere. A core of high speeds under the Southern Alps associated with a convergent margin and mountain building imaged in previous investigations is not well resolved in this study. This could suggest that such high speeds are limited in both width and depth and not resolvable by our data.

  18. Box-modeling of the impacts of atmospheric nitrogen deposition and benthic remineralization on the nitrogen cycle of the eastern tropical South Pacific

    OpenAIRE

    Su, B; M. Pahlow; Oschlies, A.

    2015-01-01

    Both atmospheric deposition and benthic remineralization influence the marine nitrogen cycle, and hence ultimately also marine primary production. The biological and biogeochemical relations of the eastern tropical South Pacific (ETSP) to nitrogen deposition, benthic denitrification and phosphate regeneration are analysed in a prognostic box model of the oxygen, nitrogen and phosphorus cycles in the ETSP. In the model, atmospheric nitrogen...

  19. Tri-locus sequence data reject a ‘‘Gondwanan origin hypothesis” for the African/South Pacific crab genus Hymenosoma

    CSIR Research Space (South Africa)

    Teske, PR

    2009-10-01

    Full Text Available Crabs of the family Hymenosomatidae are common in coastal and shelf regions throughout much of the southern hemisphere. One of the genera in the family, Hymenosoma, is represented in Africa and the South Pacific (Australia and New Zealand...

  20. School Library Development: Unesco Workshop on Training Courses for Teachers and Teacher Librarians. South Pacific Region. Contribution to the Development of Information Infrastructures.

    Science.gov (United States)

    Trask, Margaret

    As part of the Unesco School Library Development Project in the South Pacific, a selected group of librarians and a coordinator of extension studies from the region met with Unesco consultants to design and develop a general course or courses for teachers and teacher librarians on the design, production, use, and organization of learning…

  1. Temperature profile data collected using BT and XBT casts in the North/South Pacific Ocean and North/South Atlantic Ocean from NOAA Ship MALCOLM BALDRIGE and other platforms from 1988-05-04 to 1990-12-18 (NODC Accession 9100058)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected using XBT and BT casts from NOAA Ship MALCOLM BALDRIGE and other platforms in the North/South Pacific Ocean and North/South...

  2. Temperature profile data from XBT and BT casts in the North/South Pacific Ocean and North/South Atlantic Ocean from NOAA Ship RESEARCHER and other platforms from 1987-04-02 to 1987-11-24 (NODC Accession 8800007)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected using XBT and BT casts from NOAA Ship RESEARCHER and other platforms in the North/South Pacific Ocean and North/South...

  3. Partial pressure (or fugacity) of carbon dioxide, salinity and SEA SURFACE TEMPERATURE collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from ODEN in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2006-12-14 to 2006-12-26 (NODC Accession 0108159)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0108159 includes Surface underway data collected from ODEN in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60 degrees...

  4. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from POLARSTERN in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2010-11-28 to 2011-02-05 (NODC Accession 0108155)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0108155 includes discrete sample and profile data collected from POLARSTERN in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (>...

  5. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from RRS JAMES COOK in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2009-02-03 to 2009-03-03 (NODC Accession 0110379)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0110379 includes discrete sample and profile data collected from RRS JAMES COOK in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans...

  6. PH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from JAMES CLARK ROSS in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2015-12-17 to 2016-01-13 (NCEI Accession 0157011)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157011 includes chemical, discrete sample, physical and profile data collected from JAMES CLARK ROSS in the South Atlantic Ocean, South Pacific Ocean...

  7. Dissolved inorganic carbon, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from JAMES CLARK ROSS in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 1992-11-01 to 1992-12-08 (NODC Accession 0115024)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0115024 includes chemical, discrete sample, physical and profile data collected from JAMES CLARK ROSS in the South Atlantic Ocean, South Pacific Ocean...

  8. Partial pressure (or fugacity) of carbon dioxide, dissolved inorganic carbon, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the METEOR in the South Atlantic Ocean and South Pacific Ocean from 1990-01-23 to 1990-03-08 (NODC Accession 0115021)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115021 includes chemical, discrete sample, physical and profile data collected from METEOR in the South Atlantic Ocean and South Pacific Ocean from...

  9. Partial pressure (or fugacity) of carbon dioxide, dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from NATHANIEL B. PALMER in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2011-02-19 to 2011-04-23 (NODC Accession 0109933)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0109933 includes discrete sample and profile data collected from NATHANIEL B. PALMER in the South Atlantic Ocean, South Pacific Ocean and Southern...

  10. Prasinoderma singularis sp. nov. (Prasinophyceae, Chlorophyta), a solitary coccoid Prasinophyte from the South-East Pacific Ocean.

    Science.gov (United States)

    Jouenne, Fabien; Eikrem, Wenche; Le Gall, Florence; Marie, Dominique; Johnsen, Geir; Vaulot, Daniel

    2011-01-01

    During the BIOSOPE cruise in the South-East Pacific Ocean in 2004, several unidentified strains of prasinophytes were isolated into culture. Of these, nine strains composed a group for which the partial 18S rRNA gene sequence was related to Prasinoderma coloniale. The ultrastructure, morphology, division process, pigment composition, genome size and molecular genetic phylogeny of these nine strains were investigated, using P. coloniale as a reference. The 18S rRNA gene sequence of P. singularis sp. nov. shares only 96.9% of identity with that of P. coloniale and contains a conserved insertion of 567bp length not recorded in P. coloniale. When compared to P. coloniale, P. singularis sp. nov. is morphologically characterized by the absence of colonies, smaller cells with a thinner cell wall, and a second cell type with a different cell covering. 2010 Elsevier GmbH. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    Oscar Lasso-Alcalá

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

  12. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from time series observations using Bubble type equilibrator for autonomous carbon dioxide (CO2) measurement, Carbon dioxide (CO2) gas analyzer and other instruments from MOORING_TAO165E0N in the North Pacific Ocean and South Pacific Ocean from 2010-02-23 to 2013-02-03 (NODC Accession 0113238)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0113238 includes chemical, meteorological, physical and time series data collected from MOORING_TAO165E0N in the North Pacific Ocean and South Pacific...

  13. Tri-locus sequence data reject a "Gondwanan origin hypothesis" for the African/South Pacific crab genus Hymenosoma.

    Science.gov (United States)

    Teske, Peter R; McLay, Colin L; Sandoval-Castillo, Jonathan; Papadopoulos, Isabelle; Newman, Brent K; Griffiths, Charles L; McQuaid, Christopher D; Barker, Nigel P; Borgonie, Gaetan; Beheregaray, Luciano B

    2009-10-01

    Crabs of the family Hymenosomatidae are common in coastal and shelf regions throughout much of the southern hemisphere. One of the genera in the family, Hymenosoma, is represented in Africa and the South Pacific (Australia and New Zealand). This distribution can be explained either by vicariance (presence of the genus on the Gondwanan supercontinent and divergence following its break-up) or more recent transoceanic dispersal from one region to the other. We tested these hypotheses by reconstructing phylogenetic relationships among the seven presently-accepted species in the genus, as well as examining their placement among other hymenosomatid crabs, using sequence data from two nuclear markers (Adenine Nucleotide Transporter [ANT] exon 2 and 18S rDNA) and three mitochondrial markers (COI, 12S and 16S rDNA). The five southern African representatives of the genus were recovered as a monophyletic lineage, and another southern African species, Neorhynchoplax bovis, was identified as their sister taxon. The two species of Hymenosoma from the South Pacific neither clustered with their African congeners, nor with each other, and should therefore both be placed into different genera. Molecular dating supports a post-Gondwanan origin of the Hymenosomatidae. While long-distance dispersal cannot be ruled out to explain the presence of the family Hymenosomatidae on the former Gondwanan land-masses and beyond, the evolutionary history of the African species of Hymenosoma indicates that a third means of speciation may be important in this group: gradual along-coast dispersal from tropical towards temperate regions, with range expansions into formerly inhospitable habitat during warm climatic phases, followed by adaptation and speciation during subsequent cooler phases.

  14. Traditional Coping Strategies and Disaster Response: Examples from the South Pacific Region

    Science.gov (United States)

    Fletcher, Stephanie M.; Kuruppu, Natasha

    2013-01-01

    The Pacific Islands are vulnerable to climate change and increased risk of disasters not only because of their isolated and often low lying geographical setting but because of their economic status which renders them reliant on donor support. In a qualitative study exploring the adaptive capacity of Pacific Island Countries (PICs) across four countries, Cook Islands, Fiji, Samoa, and Vanuatu, it was clear that traditional coping strategies are consistently being applied as part of response to disasters and climate changes. This paper describes five common strategies employed in PICs as understood through this research: recognition of traditional methods; faith and religious beliefs; traditional governance and leadership; family and community involvement; and agriculture and food security. While this study does not trial the efficacy of these methods, it provides an indication of what methods are being used and therefore a starting point for further research into which of these traditional strategies are beneficial. These findings also provide important impetus for Pacific Island governments to recognise traditional approaches in their disaster preparedness and response processes. PMID:24454413

  15. Traditional Coping Strategies and Disaster Response: Examples from the South Pacific Region

    Directory of Open Access Journals (Sweden)

    Stephanie M. Fletcher

    2013-01-01

    Full Text Available The Pacific Islands are vulnerable to climate change and increased risk of disasters not only because of their isolated and often low lying geographical setting but because of their economic status which renders them reliant on donor support. In a qualitative study exploring the adaptive capacity of Pacific Island Countries (PICs across four countries, Cook Islands, Fiji, Samoa, and Vanuatu, it was clear that traditional coping strategies are consistently being applied as part of response to disasters and climate changes. This paper describes five common strategies employed in PICs as understood through this research: recognition of traditional methods; faith and religious beliefs; traditional governance and leadership; family and community involvement; and agriculture and food security. While this study does not trial the efficacy of these methods, it provides an indication of what methods are being used and therefore a starting point for further research into which of these traditional strategies are beneficial. These findings also provide important impetus for Pacific Island governments to recognise traditional approaches in their disaster preparedness and response processes.

  16. A qualitative ecological risk assessment of the invasive Nile tilapia, Oreochromis niloticus in a sub-tropical African river system (Limpopo River, South Africa)

    CSIR Research Space (South Africa)

    Zengeya, TA

    2013-01-01

    Full Text Available CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS Aquatic Conserv: Mar. Freshw. Ecosyst. 23: 51–64 (2013) A QUALITATIVE ECOLOGICAL RISK ASSESSMENT OF THE INVASIVE NILE TILAPIA, OREOCHROMIS NILOTICUS IN A SUB- TROPICAL AFRICAN RIVER SYSTEM (LIMPOPO RIVER... Hatfield, Pretoria, 0028 South Africa b Department of Ichthyology and Fisheries Science, Rhodes University, PO Box 94, Grahamstown, 6140 South Africa c Natural Resources and the Environment Council for Scientific and Industrial Research (CSIR), PO Box...

  17. Analysis on the cause of the abnormally persistent high temperature in south of China in July 2013

    Science.gov (United States)

    Zhang, Yu; Li, Yaohui; Wang, Jinsong

    2017-04-01

    The cause of abnormally persistent high temperature in the south of China in July 2013 was analyzed by statistical and diagnostic methods using the station observational data in July 2013 and the NCEP/NCAR reanalysis data from 1981—2013. Results indicated that the Western Pacific Subtropical High showed abnormal precursor in May 2013 and its characteristics index well pointed to the strengthening and westward and northward extension of the High. There was an advantageous condition for such weather in July: the High strengthened in the area between the south of China and Taiwan straits. As the High strengthened and kept abnormal, temperature increased in the troposphere over Eurasia. The development of the tropical cyclone in Pacific is weakened so that south winds decreased significantly in the region from 20 °S 20 °N and from 100 140 °E and north winds increased noticeably over the East Pacific. As a result, the High was sustainable and stable and even strengthened its control of the southern regions of the country. When the high temperature is abnormally persistent, the South Asia High goes persistently eastward from May to July, and its characteristic 1 660 gpdm contour is also persistently eastward. The characteristic 1 676 gpdm contour persists and goes much eastward from the 4th June. Both the South Asian High and Western Pacific Subtropical High were showing "relative motion" and "reversed motion", characteristics of oscillating from east to west during that time. Through a typical case from the 2th to 3rd of July, the eastward progression of South Asian High is found to have impact on the strengthening and westward extension of Western Pacific Subtropical High.

  18. Role of non-linear dynamics on the ventilation of the oxygen minimum zone in the eastern tropical South Pacific

    Science.gov (United States)

    José, Yonss; Oschlies, Andreas

    2015-04-01

    We analysed the role of non-linear dynamics on the ventilation of the oxygen minimum zone (OMZ) of the eastren tropical south Pacific (ETSP) by using a coupled physical-biogeochimical model. The main result showed that non-linear dynamics increases ventilation of the ETSP from the Equatorial Current System and the Peru Coastal Current (PCC). Around the Equator, the non-linear dynamics intensified the Equatorial Under-Current (EUC), increasing the eastward transport of oxygen-rich waters. This induced a shallowing of the oxygen minimum and a reduction of the OMZ thickness. By intensifying the northward transport of PCC and narrowing the Peru-Chie UnderCurrent (PCUC), the non-linear dynamics increased the northward transport of well ventilated waters from the southern origin. Further, the non-linear dynamics inhibited the northward extension of the low oxygen waters, by intensifying the southward transport of the PCUC. The reduction of outgoing flow of low oxygen waters caused a vertical expansion of the OMZ south of 6°S. These results emphasize the important role played by non-linear dynamics on the ventilation of the OMZ.

  19. ENSO and interdecadal climate variability over the last century documented by geochemical records of two coral cores from the South West Pacific

    Directory of Open Access Journals (Sweden)

    T. Ourbak

    2006-01-01

    Full Text Available The south west Pacific is affected by climatic phenomena such as ENSO (El Niño Southern Oscillation or the PDO (Pacific Decadal Oscillation. Near-monthly resolution calibrations of Sr/Ca, U/Ca and δ18Oc were made on corals taken from New Caledonia and Wallis Island. These geochemical variations could be linked to SST (sea surface temperature and SSS (sea surface salinity variations over the last two decades, itselves dependent on ENSO occurrences. On the other hand, near-half-yearly resolution over the last century smoothes seasonal and interannual climate signals, but emphasizes low frequency climate variability.

  20. Migratory preferences of humpback whales between feeding and breeding grounds in the eastern South Pacific

    NARCIS (Netherlands)

    Acevedo, Jorge; Aguayo-lobo, Anelio; Allen, Judith; Botero-acosta, Natalia; Capella, Juan; Castro, Cristina; Rosa, Luciano Dalla; Denkinger, Judith; Félix, Fernando; Flórez-gonzález, Lilian; Garita, Frank; Guzmán, Héctor M.; Haase, Ben; Kaufman, Gregory; Llano, Martha; Olavarría, Carlos; Pacheco, Aldo S.; Plana, Jordi; Rasmussen, Kristin; Scheidat, Meike; Secchi, Eduardo R.; Silva, Sebastian; Stevick, Peter T.

    2017-01-01

    Latitudinal preferences within the breeding range have been suggested for Breeding Stock G humpback whales that summer in different feeding areas of the eastern South Pacific. To address this hypothesis, humpback whales photo-identified from the Antarctic Peninsula and the Fueguian Archipelago

  1. Records of Dusky Dolphins, Lagenorhynchus obscurus (Gray, 1828) in the eastern South Pacific

    NARCIS (Netherlands)

    Waerebeek, van Koen

    1992-01-01

    Fourty-seven authenticated locality records of the dusky dolphin along the west coast of South America are presented, based on original data, museum specimens and the literature. Confirmed distribution limits are Chimbote (09°05’S) in north—central Peru and Isla Treble (55°07’S 71°02’W), Magallanes,

  2. Pattern recognition techniques in estimation of rainfall extreme events spatiotemporal characteristic: case study of a subtropical catchment in south-eastern Brazil

    Science.gov (United States)

    Laverde-Barajas, Miguel; Corzo Perez, Gerald; Solomatine, Dimitri

    2017-04-01

    Characteristics of rainfall events such as magnitude, duration and spatial extension determine the level of damage associated with natural hazards. This research uses pattern recognition techniques to estimate spatiotemporal characteristics of rainfall extreme events. A two-step approach is applied: First, the analysis in time is carried out where statistical information (mainly quantiles) is obtained for each cell. Second, a spatial 3D cluster analysis method is used to identify connected components of extreme rainfall events. This approach is applied to Near-Real-Time (NRT) satellite-derived rainfall products using connected component labelling cluster algorithm in three-dimensions. By using the 90th quantile threshold to denote an extreme condition, four types of rainfall events are defined: (1) local and short magnitude events, (2) long temporal duration events, (3) large spatially extension events and (4) spatially extended and long temporal duration events. Here a skill score evaluation of NRT satellite derived rainfall products is performed to assist the detection of these different type of extreme events. In this research, four NRT satellite products (CMORPH, PERSIANN-GCCS, TRMM-RT and the Hydro-Estimator) are compared against the recently released Multi-Source Weighted Ensemble Precipitation MSWEP (our reference model) in a subtropical catchment in southeastern Brazil during monsoon seasons from 2007 to 2014. The presented methodology allows for clustering and visual representation of spatial intensity, location and extension, as well as for classifying the dominant type of events in the region. Results show that CMORPH showed the best performance (close to the reference) for identifying different types of spatiotemporal extreme events in the study area. Further research is aimed at linking this approach to hydrological flood modelling.

  3. Geostrophic volume transport and eddies in the region of sub-tropical and sub-Antarctic waters south of Madagascar during austral summer (January–February) 2004

    Digital Repository Service at National Institute of Oceanography (India)

    RameshBabu, V.; Somayajulu, Y.K.; Sudhakar, M.

    observed from Geosat. J. Geophys. Res., 1990, 95, 17865–17876. 8. Park, Y. H. and Gamberoni, L., Large-sale circulation and its vari- ability in the south Indian Ocean from TOPEX/POSEIDON altim- etry. J. Geophys. Res., 1995, 100(C2), 24911–24929. 9...

  4. Improving the Operational Methodology of Tropical Cyclone Seasonal Prediction in the Australian and the South Pacific Ocean Regions

    Directory of Open Access Journals (Sweden)

    J. S. Wijnands

    2014-01-01

    Full Text Available Tropical cyclones (TCs can have a major impact on the coastal communities of Australia and Pacific Island countries. Preparedness is one of the key factors to limit TC impacts and the Australian Bureau of Meteorology issues an outlook of TC seasonal activity ahead of TC season for the Australian Region (AR; 5°S to 40°S, 90°E to 160°E and the South Pacific Ocean (SPO; 5°S to 40°S, 142.5°E to 120°W. This paper investigates the use of support vector regression models and new explanatory variables to improve the accuracy of seasonal TC predictions. Correlation analysis and subsequent cross-validation of the generated models showed that the Dipole Mode Index (DMI performs well as an explanatory variable for TC prediction in both AR and SPO, Niño4 SST anomalies—in AR and Niño1+2 SST anomalies—in SPO. For both AR and SPO, the developed model which utilised the combination of Niño1+2 SST anomalies, Niño4 SST anomalies, and DMI had the best forecasting performance. The support vector regression models outperform the current models based on linear discriminant analysis approach for both regions, improving the standard deviation of errors in cross-validation from 2.87 to 2.27 for AR and from 4.91 to 3.92 for SPO.

  5. Tracking Australian Dust to the South Pacific Over the Last Glacial Cycle

    Science.gov (United States)

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

    2016-12-01

    Dust, emitted from continents and swept into the atmosphere, has far-reaching impacts on the climate system. Wind-borne dusts can influence atmospheric reflectivity, and can also drive terrestrial and marine biological activity by supplying necessary micronutrients to habitats. We can also use dust particles that we retrieve from climate archives (such as marine sediment cores) to trace changes in dust source areas over time, by comparing the geochemical "fingerprint" of known terrestrial source areas with the signature of dust found in the core. Australia is currently the largest and most important dust source in the Southern Hemisphere, but its role in the past is not well known. There are two major dust plumes coming off the continent, and the southeast pathway distributes dust over the southern Pacific Ocean/Southern Ocean, and beyond. In this study, we extracted dust particles from marine sediment core ELT39-75, a core from a site in the Tasman Sea that sits directly within the modern southeast Australian dust plume: we chose this site in order to identify the purely Australian signature of dust coming off the continent, which in turn helps us understand signals found further downwind (Hesse, 1994). We geochemically "fingerprint" the dust using trace elements and radiogenic isotope signatures (87Sr/86Sr, ɛNd, and Pb isotopes) and compare those signatures to previously reported and newly analyzed Australian source area dust samples. We then identify precisely where in Australia dust emissions come from and how those source areas have changed over the last glacial-interglacial climate cycle, from 130ky bp through the Holocene. These results will help us model and interpret downfield dust records, because knowing the dust source to the Tasman Sea informs us about what dusts are sourcing the southern Pacific Ocean and Antarctica. They also give us insight into climate conditions at the Australian sources.

  6. Physical and underway data collected aboard the ROGER REVELLE during cruise RR0901 in the South Pacific Ocean from 2009-01-12 to 2009-02-17 (NODC Accession 0089623)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089623 includes physical and underway data collected aboard the ROGER REVELLE during cruise RR0901 in the South Pacific Ocean from 2009-01-12 to...

  7. Physical and underway data collected aboard the ROGER REVELLE during cruise RR1509 in the South Pacific Ocean from 2015-06-20 to 2015-06-30 (NCEI Accession 0145840)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0145840 includes physical and underway data collected aboard the ROGER REVELLE during cruise RR1509 in the South Pacific Ocean from 2015-06-20 to...

  8. North and South Pacific Ocean Temperature Profile Data for the High Resolution XBT Network for PX37, PX10, and PX44 were collected by the Scripps Institute of Oceanography from March 2001 to June 2009 (NODC Accession 0056790)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Physical data were collected from XBT casts from the North and South Pacific Oceans. Data were collected from March 2001 to June 2009. Data were collected and...

  9. Chemical, optical and other data collected aboard the MELVILLE during cruise MV1104 in the South Pacific Ocean from 2011-03-23 to 2011-04-23 (NCEI Accession 0130851)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0130851 includes chemical, optical and other data collected aboard the MELVILLE during cruise MV1104 in the South Pacific Ocean from 2011-03-23 to...

  10. Chemical, optical and other data collected aboard the THOMAS G. THOMPSON during cruise TN235 in the South Pacific Ocean from 2009-05-16 to 2009-06-08 (NODC Accession 0104352)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0104352 includes chemical, optical and other data collected aboard the THOMAS G. THOMPSON during cruise TN235 in the South Pacific Ocean from...

  11. Chemical, optical and physical data collected aboard the MELVILLE during cruise MV1001 in the Indian Ocean and South Pacific Ocean from 2009-03-21 to 2010-02-10 (NCEI Accession 0089611)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0089611 includes chemical, optical and physical data collected aboard the MELVILLE during cruise MV1001 in the Indian Ocean and South Pacific Ocean...

  12. Temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the KNORR in the South Pacific Ocean from 2006-01-30 to 2006-03-14 (NODC Accession 0115593)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115593 includes chemical, discrete sample, physical and profile data collected from KNORR in the South Pacific Ocean from 2006-01-30 to 2006-03-14...

  13. Physical and underway data collected aboard the ROGER REVELLE during cruise RR1508 in the South Pacific Ocean from 2015-05-19 to 2015-06-17 (NCEI Accession 0145839)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0145839 includes physical and underway data collected aboard the ROGER REVELLE during cruise RR1508 in the South Pacific Ocean from 2015-05-19 to...

  14. Physical and underway data collected aboard the ROGER REVELLE during cruise RR0915 in the South Pacific Ocean from 2009-11-20 to 2009-12-04 (NODC Accession 0089673)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089673 includes physical and underway data collected aboard the ROGER REVELLE during cruise RR0915 in the South Pacific Ocean from 2009-11-20 to...

  15. Physical, profile and underway data collected aboard the ROGER REVELLE during cruise RR1210 in the South Pacific Ocean from 2012-08-31 to 2012-09-06 (NCEI Accession 0145834)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0145834 includes physical, profile and underway data collected aboard the ROGER REVELLE during cruise RR1210 in the South Pacific Ocean from...

  16. Temperature profile and other data collected using CTD casts in the North/South Pacific Ocean from NOAA Ship MALCOLM BALDRIGE and other platform from 1990-02-23 to 1990-12-06 (NODC Accession 9200013)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile and other data were collected using CTD casts from NOAA Ship MALCOLM BALDRIGE and NOAA Ship DISCOVERER in the North/South Pacific Ocean from 23...

  17. Current meter and other data from current meter casts from NOAA Ship RESEARCHER in the North and South Pacific Ocean from 1984-06-28 to 1984-07-01 (NODC Accession 8500226)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Current meter and other data were collected using current meter casts from NOAA Ship RESEARCHER in the North/South Pacific Ocean from June 28, 1984 to July 1, 1984....

  18. Temperature profile and other data collected using CTD casts in the North/South Pacific Ocean from NOAA Ship MALCOLM BALDRIGE and other platform from 16 February 1991 to 98 December 1991 (NODC Accession 9200156)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile and other data were collected using CTD casts from NOAA Ship MALCOLM BALDRIGE and NOAA Ship DISCOVERER in the North/South Pacific Ocean from 16...

  19. Temperature profile and chemical data collected using BT and XBT casts from NOAA Ship RESEARCHER in the North/South Pacific Ocean and Caribbean Sea from 1987-04-07 to 1987-09-30 (NODC Accession 8700382)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile and chemical data were collected using XBT and BT casts from NOAA Ship RESEARCHER in the North/South Pacific Ocean and Caribbean Sea from 07...

  20. Physical and underway data collected aboard the THOMAS G. THOMPSON during cruise TN234 in the South Pacific Ocean from 2009-05-05 to 2009-05-13 (NODC Accession 0104351)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0104351 includes physical and underway data collected aboard the THOMAS G. THOMPSON during cruise TN234 in the South Pacific Ocean from 2009-05-05 to...

  1. Physical and underway data collected aboard the ROGER REVELLE during cruise RR0917 in the South Pacific Ocean from 2009-12-18 to 2009-12-22 (NODC Accession 0089675)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089675 includes physical and underway data collected aboard the ROGER REVELLE during cruise RR0917 in the South Pacific Ocean from 2009-12-18 to...

  2. Temperature profile and other data from CTD casts in the South Pacific Ocean from NOAA Ship RESEARCHER from 1982-11-21 to 1983-07-24 (NODC Accession 8400113)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile and other data were collected using CTD casts from NOAA Ship RESEARCHER in the South Pacific Ocean from 21 November 1982 to 24 July 1983. Data...

  3. Physical and underway data collected aboard the ROGER REVELLE during cruise KNOX03RR in the Indian Ocean, South Pacific Ocean and others from 2007-02-04 to 2007-03-17 (NCEI Accession 0155647)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0155647 includes physical and underway data collected aboard the ROGER REVELLE during cruise KNOX03RR in the Indian Ocean, South Pacific Ocean and...

  4. Physical and underway data collected aboard the MELVILLE during cruise MGLN07MV in the South Pacific Ocean from 2006-09-05 to 2006-10-02 (NODC Accession 0098567)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0098567 includes physical and underway data collected aboard the MELVILLE during cruise MGLN07MV in the South Pacific Ocean from 2006-09-05 to...

  5. CRED Simrad em3002d multibeam backscatter data from the banktop and bank edge environments at Tutuila, American Samoa, South Pacific with 1 meter resolution in GeoTIFF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Tutuila, American Samoa, South Pacific These data provide coverage between 20 and 5000 meters. The...

  6. Physical and underway data collected aboard the MELVILLE during cruise MV1004 in the South Pacific Ocean from 2010-03-17 to 2010-03-25 (NODC Accession 0089613)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089613 includes physical and underway data collected aboard the MELVILLE during cruise MV1004 in the South Pacific Ocean from 2010-03-17 to...

  7. Temperature profile and water depth data collected from HMAS DARWIN and other platforms using BT and XBT casts in the North / South Pacific Ocean and Indian Ocean from 29 April 1985 to 12 April 1988 (NODC Accession 8800166)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile and water depth data were collected using BT and XBT casts from the HMAS DARWIN and other platforms in the North / South Pacific Ocean and Indian...

  8. Nutrients and zooplankton data from net and bottle casts from the ALAMINOS and other platforms from the South Pacific Ocean and other locations from 31 January 1967 to 23 September 1967 (NODC Accession 9500089)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Nutrients and zooplankton data were collected from net and bottle casts from the ALAMINOS and other platforms in the South Pacific Ocean and other locations. Data...

  9. Oceanographic Station Data from bottle casts in the South Pacific Ocean and other locations from the CARLOS PORTE from 27 November 1980 to 18 December 1982 (NODC Accession 8500242)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Oceanographic Station Data were collected from bottle casts in the South Pacific Ocean from the CARLOS PORTE. Data were collected from 27 November 1980 to 18...

  10. Temperature profile and other data collected from XBT casts in South Pacific Ocean from BOTANY BAY and other platforms from 24 January 1991 to 20 November 1991 (NODC Accession 9400208)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile and other data were collected using XBT casts from BOTANY BAY and other platforms in South Pacific Ocean. Data were collected from 24 January...

  11. Physical and underway data collected aboard the ROGER REVELLE during cruise RR1507 in the South Pacific Ocean from 2015-04-20 to 2015-05-14 (NCEI Accession 0145838)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0145838 includes physical and underway data collected aboard the ROGER REVELLE during cruise RR1507 in the South Pacific Ocean from 2015-04-20 to...

  12. Chemical, optical and other data collected aboard the MELVILLE during cruise MV1015 in the South Pacific Ocean from 2010-11-17 to 2010-12-14 (NCEI Accession 0089622)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0089622 includes chemical, optical and other data collected aboard the MELVILLE during cruise MV1015 in the South Pacific Ocean from 2010-11-17 to...

  13. Physical and underway data collected aboard the ATLANTIS during cruise AT15-61 in the South Pacific Ocean from 2010-01-29 to 2010-03-03 (NODC Accession 0103916)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0103916 includes physical and underway data collected aboard the ATLANTIS during cruise AT15-61 in the South Pacific Ocean from 2010-01-29 to...

  14. Physical, profile and underway data collected aboard the MELVILLE during cruise MV1205 in the South Pacific Ocean from 2012-04-20 to 2012-04-30 (NCEI Accession 0129823)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0129823 includes physical, profile and underway data collected aboard the MELVILLE during cruise MV1205 in the South Pacific Ocean from 2012-04-20 to...

  15. Temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from THOMAS G. THOMPSON in the South Pacific Ocean from 2013-10-25 to 2013-12-20 (NCEI Accession 0163186)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0163186 includes chemical, discrete sample, physical and profile data collected from THOMAS G. THOMPSON in the South Pacific Ocean from 2013-10-25 to...

  16. Physical and underway data collected aboard the MELVILLE during cruise MV1206 in the South Pacific Ocean from 2012-05-04 to 2012-05-18 (NCEI Accession 0131930)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0131930 includes physical and underway data collected aboard the MELVILLE during cruise MV1206 in the South Pacific Ocean from 2012-05-04 to...

  17. CRED Simrad em3002d multibeam backscatter data from the banktop and bank edge environments at Tutuila, American Samoa, South Pacific with 1 meter resolution in netCDF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Tutuila, American Samoa, South Pacific These data provide coverage between 20 and 5000 meters. The...

  18. CRED Simrad em3002d multibeam backscatter data from the banktop and bank edge environments at Tutuila, American Samoa, South Pacific with 16 meter resolution in GeoTIFF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Tutuila, American Samoa, South Pacific These data provide coverage between 20 and 5000 meters. The...

  19. Physical, Chemical, and Biological CTD and Bottle data from NATHANIEL B. PALMER in Eastern Tropical South Pacific Ocean near Peru/Chile from 2013-06-24 to 2013-07-22 (NCEI Accession 0128141)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This report contains data from R/V Nathaniel B. Palmer cruise NBP 1305 to the eastern tropical south pacific oxygen deficient zone. The objective of the cruise was...

  20. CRED Simrad em3002d multibeam backscatter data from the banktop and bank edge environments at Tutuila, American Samoa, South Pacific with 16 meter resolution in netCDF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Tutuila, American Samoa, South Pacific These data provide coverage between 20 and 5000 meters. The...

  1. Chemical, optical and other data collected aboard the MELVILLE during cruise MV1103 in the South Pacific Ocean from 2011-03-15 to 2011-03-20 (NCEI Accession 0130850)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0130850 includes chemical, optical and other data collected aboard the MELVILLE during cruise MV1103 in the South Pacific Ocean from 2011-03-15 to...

  2. Distribution of lipid biomarkers and carbon isotope fractionation in contrasting trophic environments of the South East Pacific

    Directory of Open Access Journals (Sweden)

    I. Tolosa

    2008-06-01

    Full Text Available The distribution of lipid biomarkers and their stable carbon isotope composition was investigated on suspended particles from different contrasting trophic environments at six sites in the South East Pacific. High algal biomass with diatom-related lipids (24-methylcholesta-5,24(28-dien-3β-ol, C25 HBI alkenes, C16:4 FA, C20:5 FA was characteristic in the upwelling zone, whereas haptophyte lipids (long-chain (C37-C39 unsaturated ketones were proportionally most abundant in the nutrient-poor settings of the centre of the South Pacific Gyre and on its easter edge. The dinoflagellate–sterol, 4α-23,24-trimethylcholest-22(E-en-3β-ol, was a minor contributor in all of the studied area and the cyanobacteria-hydrocarbon, C17n-alkane, was at maximum in the high nutrient low chlorophyll regime of the subequatorial waters near the Marquesas archipelago.

    The taxonomic and spatial variability of the relationships between carbon photosynthetic fractionation and environmental conditions for four specific algal taxa (diatoms, haptophytes, dinoflagellates and cyanobacteria was also investigated. The carbon isotope fractionation factor (εp of the 24-methylcholesta-5,24(28-dien-3β-ol diatom marker, varied over a range of 16% along the different trophic systems. In contrast, εp of dinoflagellate, cyanobacteria and alkenone markers varied only by 7–10‰. The low fractionation factors and small variations between the different phytoplankton markers measured in the upwelling area likely reveals uniformly high specific growth rates within the four phytoplankton taxa, and/or that transport of inorganic carbon into phytoplankton cells may not only occur by diffusion but also by other carbon concentrating mechanisms (CCM. In contrast, in the oligotrophic zone, i.e. gyre and eastgyre, relatively high εp values, especially for the diatom marker

  3. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the HAKUREI MARU in the North Pacific Ocean and South Pacific Ocean from 1993-04-13 to 1993-06-11 (NODC Accession 0112228)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112228 includes biological, chemical, discrete sample, physical and profile data collected from HAKUREI MARU in the North Pacific Ocean and South...

  4. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the HAKUREI MARU in the North Pacific Ocean and South Pacific Ocean from 1992-08-07 to 1992-10-05 (NODC Accession 0112227)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112227 includes biological, chemical, discrete sample, physical and profile data collected from HAKUREI MARU in the North Pacific Ocean and South...

  5. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the JOHN V. VICKERS in the Bering Sea, North Pacific Ocean and South Pacific Ocean from 1992-08-16 to 1992-10-21 (NODC Accession 0115003)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115003 includes chemical, discrete sample, physical and profile data collected from JOHN V. VICKERS in the Bering Sea, North Pacific Ocean and South...

  6. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the L'ATALANTE in the Coral Sea, North Pacific Ocean and South Pacific Ocean from 1994-09-23 to 1994-10-29 (NODC Accession 0111870)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0111870 includes chemical, discrete sample, physical and profile data collected from L'ATALANTE in the Coral Sea, North Pacific Ocean and South...

  7. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the KEIFU MARU in the North Pacific Ocean and South Pacific Ocean from 2008-06-17 to 2008-08-03 (NODC Accession 0112336)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112336 includes biological, chemical, discrete sample, physical and profile data collected from KEIFU MARU in the North Pacific Ocean and South...

  8. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the HAKUREI MARU in the North Pacific Ocean and South Pacific Ocean from 1993-08-07 to 1993-10-05 (NODC Accession 0112229)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112229 includes biological, chemical, discrete sample, physical and profile data collected from HAKUREI MARU in the North Pacific Ocean and South...

  9. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and Calcium collected from discrete sample and profile observations using CTD, bottle and other instruments from NOAA Ship MILLER FREEMAN in the North Pacific Ocean and South Pacific Ocean from 1979-04-01 to 1982-06-30 (NODC Accession 0000180)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0000180 includes chemical, discrete sample, physical and profile data collected from NOAA Ship MILLER FREEMAN in the North Pacific Ocean and South...

  10. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the RYOFU MARU in the North Pacific Ocean and South Pacific Ocean from 1999-09-17 to 1999-11-09 (NODC Accession 0115279)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115279 includes biological, chemical, discrete sample, physical and profile data collected from RYOFU MARU in the North Pacific Ocean and South...

  11. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the Ryofu Maru II in the North Pacific Ocean and South Pacific Ocean from 2007-01-18 to 2007-03-12 (NODC Accession 0112294)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112294 includes biological, chemical, discrete sample, physical and profile data collected from Ryofu Maru II in the North Pacific Ocean and South...

  12. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the Ryofu Maru II in the North Pacific Ocean and South Pacific Ocean from 2007-06-06 to 2007-07-24 (NODC Accession 0112295)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112295 includes biological, chemical, discrete sample, physical and profile data collected from Ryofu Maru II in the North Pacific Ocean and South...

  13. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the RYOFU MARU in the North Pacific Ocean and South Pacific Ocean from 1997-09-12 to 1997-11-07 (NODC Accession 0115286)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115286 includes biological, chemical, discrete sample, physical and profile data collected from RYOFU MARU in the North Pacific Ocean and South...

  14. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the RYOFU MARU in the North Pacific Ocean and South Pacific Ocean from 2002-10-01 to 2002-11-27 (NODC Accession 0115283)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115283 includes biological, chemical, discrete sample, physical and profile data collected from RYOFU MARU in the North Pacific Ocean and South...

  15. Dissolved inorganic carbon, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from NOAA Ship MALCOLM BALDRIGE in the North Pacific Ocean, South Pacific Ocean and Southern Oceans from 1990-02-22 to 1990-04-16 (NODC Accession 0000183)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0000183 includes chemical, discrete sample, physical and profile data collected from NOAA Ship MALCOLM BALDRIGE in the North Pacific Ocean, South...

  16. Dissolved inorganic carbon, pH, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from MIRAI in the North Pacific Ocean and South Pacific Ocean from 2002-01-07 to 2002-02-16 (NODC Accession 0112354)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0112354 includes biological, chemical, discrete sample, optical, physical and profile data collected from MIRAI in the North Pacific Ocean and South...

  17. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the HAKUREI MARU in the North Pacific Ocean and South Pacific Ocean from 1994-04-13 to 1994-06-11 (NODC Accession 0112230)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112230 includes biological, chemical, discrete sample, physical and profile data collected from HAKUREI MARU in the North Pacific Ocean and South...

  18. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the HAKUREI MARU in the North Pacific Ocean and South Pacific Ocean from 1994-08-08 to 1994-10-06 (NODC Accession 0112339)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112339 includes biological, chemical, discrete sample, physical and profile data collected from HAKUREI MARU in the North Pacific Ocean and South...

  19. Dissolved inorganic carbon, pH, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from MIRAI in the North Pacific Ocean and South Pacific Ocean from 1999-11-21 to 1999-12-27 (NODC Accession 0112351)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0112351 includes biological, chemical, discrete sample, optical, physical and profile data collected from MIRAI in the North Pacific Ocean and South...

  20. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the RYOFU MARU in the North Pacific Ocean and South Pacific Ocean from 1998-09-16 to 1998-11-13 (NODC Accession 0115280)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115280 includes biological, chemical, discrete sample, physical and profile data collected from RYOFU MARU in the North Pacific Ocean and South...

  1. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the RYOFU MARU in the North Pacific Ocean and South Pacific Ocean from 2011-05-15 to 2011-08-26 (NODC Accession 0115178)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115178 includes biological, chemical, discrete sample, physical and profile data collected from RYOFU MARU in the North Pacific Ocean and South...

  2. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the RYOFU MARU in the North Pacific Ocean and South Pacific Ocean from 2000-09-20 to 2000-11-04 (NODC Accession 0115288)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115288 includes biological, chemical, discrete sample, physical and profile data collected from RYOFU MARU in the North Pacific Ocean and South...

  3. The potential for using tree-ring data from Jeju-island to reconstruct climate in subtropical Korea - A pilot study

    Science.gov (United States)

    Jeong, Ji-Yoon; Jeong, Jee-Hoon; Kim, Baek-Min; Linderholm, Hans W.

    2017-04-01

    Annual rings from trees have been used to understand past climate variability beyond the observational records which started usually after 1950s. Here, as a preliminary study, we assess the possibility of using two conifer species from the humid subtropical island of Jeju, South Korea, as proxies for past regional climate variability of Korea and the Western North Pacific. Korean red pine (Pinus densiflora) and Korean fir (Abies koreana) were sampled on the southern slopes of the volcanic Mt. Halla at 1320 m and 1640 m a.s.l., respectively. Comparison with climate variables from a nearby meteorological station over the 1981-2011 period we found the strong positive association between temperature in January-May and Korean red pine growth, and positive association between precipitation in October and Korean fir. Moreover, the pine tree showed significant multi-month associations with both sea surface temperatures over the Western North Pacific and the Kuroshio Extension variability. Despite limitations in this pilot study, the results suggest a possibility of using subtropical trees from South Korea as indicators of past climate variability on local to regional scales.

  4. Distribution of surface plastic debris in the eastern Pacific Ocean from an 11-year data set.

    Science.gov (United States)

    Law, Kara Lavender; Morét-Ferguson, Skye E; Goodwin, Deborah S; Zettler, Erik R; Deforce, Emelia; Kukulka, Tobias; Proskurowski, Giora

    2014-05-06

    We present an extensive survey of floating plastic debris in the eastern North and South Pacific Oceans from more than 2500 plankton net tows conducted between 2001 and 2012. From these data we defined an accumulation zone (25 to 41 °N, 130 to 180 °W) in the North Pacific subtropical gyre that closely corresponds to centers of accumulation resulting from the convergence of ocean surface currents predicted by several oceanographic numerical models. Maximum plastic concentrations from individual surface net tows exceeded 10(6) pieces km(-2), with concentrations decreasing with increasing distance from the predicted center of accumulation. Outside the North Pacific subtropical gyre the median plastic concentration was 0 pieces km(-2). We were unable to detect a robust temporal trend in the data set, perhaps because of confounded spatial and temporal variability. Large spatiotemporal variability in plastic concentration causes order of magnitude differences in summary statistics calculated over short time periods or in limited geographic areas. Utilizing all available plankton net data collected in the eastern Pacific Ocean (17.4 °S to 61.0 °N; 85.0 to 180.0 °W) since 1999, we estimated a minimum of 21,290 t of floating microplastic.

  5. Organochlorine pollutants in small cetaceans from the Pacific and south Atlantic Oceans, November 1968-June 1976

    Energy Technology Data Exchange (ETDEWEB)

    O' Shea, T.J.; Brownell, R.L. Jr.; Clark, D.R. Jr.; Walker, W.A.; Gay, M.L.; Lamont, T.G.

    1980-09-01

    Organochlorine residues were analyzed in blubber, brain, or muscle tissues of 69 individuals representing 10 species of small cetaceans. Collections were made from November 1968 through June 1976 at localities in the Eastern Tropical Pacific and along the coasts of California, Hawaii, Japan, and Uruguay, Relations of residue concentrations between tissues are described for DDE and PCBs in two dolphin species. sigma DDT and PCB residues in blubber of most of the 19 individuals of the five southern California species sampled exceed concentrations that are associated with reproductive impairment in pinnipeds, although the nature of such associations is not well defined. The sigma DDT residue of 2,695 ppm in blubber of one California coastal Tursiops truncatus is one of the highest concentrations reported in tissues of members of any population of wild mammals. Except for one rough-toothed dolphin (Steno bredanensis) from Maui, Hawaii, all individuals from all localities surveyed were contaminated with organochlorine compounds. Seventeen different organochlorines were detected; greatest diversity occurred near Japan and California. This is the first report of several of these compounds in tissues of any species of marine mammals. The o,p'-isomers and metabolites of DDT were detected unusually frequently. Ratios of p,p'-DDT to p,p'-DDE in blubber of cetaceans from waters off countries where use of this pesticide has been relatively recent and ongoing were at least an order of magnitude higher than in cetaceans from United States waters.

  6. Ocean feedback on tropical cyclone intensity in a multidecadal coupled simulation of the South Pacific

    Science.gov (United States)

    Jullien, Swen; Marchesiello, Patrick; Menkes, Christophe; Lefevre, Jérôme; Jourdain, Nicolas; Lengaigne, Matthieu; Samson, Guillaume

    2014-05-01

    Tropical cyclone (TC)-ocean interactions are essential for cyclone formation and evolution. Surface cooling is observed in the cyclone wake and is expected to exert a negative feedback to the storm intensity. Its quantification is assessed with a coupled regional model of the southwest Pacific developed for present climate simulations at mesoscale resolution. The feedback of the ocean response is investigated for the first time by comparing 20-year forced and coupled experiments. This provides statistically robust experiments filling a gap between coarse-resolution and short-term studies. The intensity distribution is significantly affected but the SST feedback is of moderate amplitude (5-15 hPa/Celsius) compared with theoretical models. Our analysis contradicts the direct thermodynamic control of TC intensification by surface moisture fluxes in favor of a storm-scale dynamic control. In addition, regional oceanography strongly modulates TC-ocean coupling. It is stronger in the Coral Sea that has shallow mixed layer and numerous eddies but extremely weak in the warm pool that has deep mixed layer, thick barrier layer and no mesoscale activity. These pre-conditions to SST cooling impact the TC distribution.

  7. Seasonal cycles of surface layer salinity in the Pacific Ocean

    Directory of Open Access Journals (Sweden)

    F. M. Bingham

    2010-08-01

    region near the equator. Entrainment was found to be mostly not significant except for a small region along 2.5–7.5° N in the eastern Pacific.

    Averaged spatially over large areas in the western North Pacific, ITCZ, South Pacific and northern North Pacific, the seasonal cycle is mostly a balance between changes in SLS and E-P, with entrainment and advection playing relatively minor roles.

    This work highlights the potentially significant role of surface salinity in the hydrologic cycle and in subtropical mode water formation. It can also help to interpret measurements that will soon be available from the Aquarius and SMOS (Soil Moisture and Ocean Salinity satellite missions.

  8. Two aspects along the continuum of pigeon evolution: A South-Pacific radiation and the relationship of pigeons within Neoaves.

    Science.gov (United States)

    Gibb, Gillian C; Penny, David

    2010-08-01

    Phylogenetics explores the continuum of shallower to deeper genetic divergences between taxa. Along this continuum increasing lengths of DNA sequence can be used to answer deeper and deeper questions about biological relationships. We use shorter, and then longer mitochondrial DNA sequences to address two aspects of pigeon evolution. Firstly, we examine the phylogenetic relationships of the eight genera within the South Pacific Ducula-Ptilinopus radiation, and examine how this radiation fits into pigeons generally. Within Ducula, taxa are closely related, whereas Ptilinopus is very diverse, and paraphyletic. One third of all pigeon species are within the Ducula-Ptilinopus radiation, however all are very similar ecologically. Secondly, we study the deeper phylogenetic question regarding the relationship of pigeons to other birds. To this end, we report the complete mitochondrial genome of Hemiphaganovaeseelandiae, a member of the Ducula-Ptilinopus radiation. We use this mitochondrial genome, along with additional sandgrouse (Pterocles namaqua) mitochondrial genes to assess various candidates for the closest relative of pigeons. Of parrots, shorebirds, and sandgrouse, we find highest support for the sandgrouse-pigeon grouping. Furthermore in these analyses the pigeon and sandgrouse group closer to the falcons than any other included taxon. The finding that pigeons and sandgrouse may be more closely related to falcons than to previous candidates such as shorebirds or parrots invites further investigation. Copyright 2010 Elsevier Inc. All rights reserved.

  9. Mantle plumes beneath the South Pacific superswell revealed by finite frequency P tomography using regional seafloor and island data

    Science.gov (United States)

    Obayashi, M.; Yoshimitsu, J.; Sugioka, H.; Ito, A.; Isse, T.; Shiobara, H.; Reymond, D.; Suetsugu, D.

    2016-11-01

    We present a new tomographic image beneath the South Pacific superswell, using finite frequency P wave travel time tomography with global and regional data. The regional stations include broadband ocean-bottom seismograph stations. The tomographic image shows slow anomalies of 200-300 km in diameter beneath most hot spots in the studied region, extending continuously from the shallow upper mantle to 400 km depth. Narrow and weak slow anomalies are detected at depths of 500-1000 km, connecting the upper mantle slow anomalies with large-scale slow anomalies with lateral dimension of 1000-2000 km prevailing below 1000 km depth down to the core-mantle boundary. There are two slow anomalies around the Society hot spot at depths shallower than 400 km, which both emerge from the same slow anomaly at 500 km depth. One of them is located beneath the Society hot spot and the other underlies 500 km east of the Society hot spot, where no volcanism is observed.

  10. An Unprecedented High Incidence of Leptospirosis in Futuna, South Pacific, 2004 – 2014, Evidenced by Retrospective Analysis of Surveillance Data

    Science.gov (United States)

    Massenet, Denis; Yvon, Jean-François; Couteaux, Clément; Goarant, Cyrille

    2015-01-01

    Futuna is a small Polynesian island in the South Pacific with a population of 3,612 in 2013. The first human leptospirosis case was confirmed in 1997. Active surveillance started in 2004. Cases were confirmed by PCR or real time PCR, or by serology using MAT or a combination of IgM-ELISA and MAT. A retrospective analysis of surveillance data shows that the disease was endemic with a mean annual incidence of 844 cases per 100,000 over an 11-year period from 2004 to 2014. An epidemic peak as high as 1,945 cases per 100,000 occurred in 2008. Serogroup Australis was predominant until 2007, Icterohaemorrhagiae was dominant afterwards. Cluster analysis revealed different hot spots over time. Lifestyle habits, such as walking barefoot in irrigated taro fields or pig pens probably contributed to contamination from the swine and rodent reservoirs to humans. Severe forms were rare, and the case fatality rate was 0.5%. The medical community and general population were aware of leptospirosis and rapid treatment with amoxycillin was the main treatment, probably contributing to this low fatality rate. PMID:26528546

  11. FACTORS CAUSING DIFFERENCES IN THE FINANCIAL REPORTING PRACTICES IN SELECTED SOUTH PACIFIC COUNTRIES IN THE POST-CONVERGENCE PERIOD

    Directory of Open Access Journals (Sweden)

    Parmod Chand

    2008-01-01

    Full Text Available The international accounting literature pays much attention to the clustering of national accounting systems of various countries based on similar financial reporting characteristics. In this paper, we argue that the existing models that cluster countries are substantially incomplete and misleading due to the recent convergence efforts that have taken place. We identify the factors that may be causing differences in both the de jure and de facto aspects of comparability in financial reporting across countries in the post-convergence period. Using four countries from the South Pacific region (Australia, New Zealand, Papua New Guinea and Fiji, we identify three dominant factors that still act as constraints in accounting convergence. These include: (1 the nature of business ownership and the financial system, (2 culture, and (3 the level of accounting education and the experience of professional accountants in each of the different countries. We argue that national and international regulators need to work towards reducing these remaining differences across countries to achieve the objectives of accounting convergence.

  12. Millennial-scale climate variability in the south-eastern North America and the subtropical North Atlantic during the last glacial period: a land-sea correlation derived from the pollen rich marine core MD99-2203

    Science.gov (United States)

    Lopez-Martinez, C.; Sanchez Goñi, M. F.; Desprat, S.; Rossignol, L.

    2009-04-01

    subtropical region (Sánchez Goñi et al., 2000; Naughton et al., submitted) provide better understanding of the impact of millennial scale climate variability over the last glacial period in the subtropical North Atlantic. The pollen sequence from core MD99-2203 shows, for the first time, that changes in forest formations associated with last glacial abrupt climate changes were smoother in south-eastern North America than in the Iberian Peninsula (López-Martínez et al., in preparation) Grimm et al., 1993. Science, 261: 198-200. Grimm et al., 2006. Quat. Sci. Rev., 25: 2197-2211. López-Martínez et al., 2006. Paleoceanography, 21: PA4215, doi:10.1029/2006PA001275. Naughton et al., Earth Planet. Sci. Lett., submitted. Sánchez Goñi et al., 2000. Quat. Res., 54: 394-403. Vautravers et al., 2004. Paleoceanography, 19(PA2011): doi:10.1029/2003PA000966. Voelker et al., 2002. Quat. Sci. Rev., 21: 1185-1212.

  13. Southwest Pacific Ocean Circulation and Climate Experiment (SPICE) scientific advances and future west pacific coordination

    Science.gov (United States)

    Ganachaud, A. S.; Sprintall, J.; Lin, X.; Ando, K.

    2016-02-01

    The Southwest Pacific Ocean Circulation and Climate Experiment (SPICE) is an international research program under the auspices of CLIVAR (Climate Variability and Predictability). The key objectives are to understand the Southwest Pacific Ocean circulation and Convergence Zone (SPCZ) dynamics, as well as their influence on regional and basin-scale climate patterns. It was designed to measure and monitor the ocean circulation, and to validate and improve numerical models. South Pacific oceanic waters are carried from the subtropical gyre centre in the westward flowing South Equatorial Current (SEC), towards the southwest Pacific-a major circulation pathway that redistributes water from the subtropics to the equator and Southern Ocean. Water transit through the Coral and Solomon Seas is potentially of great importance to tropical climate prediction because changes in either the temperature or the amount of water arriving at the equator have the capability to modulate ENSO and produce basin-scale climate feedbacks. On average, the oceanic circulation is driven by the Trade Winds, and subject to substantial variability, related with the SPCZ position and intensity. The circulation is complex, with the SEC splitting into zonal jets upon encountering island archipelagos, before joining either the East Australian Current or the New Guinea Costal UnderCurrent towards the equator. SPICE included large, coordinated in situ measurement programs and high resolution numerical simulations of the area. After 8 years of substantial in situ oceanic observational and modeling efforts, our understanding of the region has much improved. We have a refined description of the SPCZ behavior, boundary currents, pathways, and water mass transformation, including the previously undocumented Solomon Sea. The transports are large and vary substantially in a counter-intuitive way, with asymmetries and gating effects that depend on time scales. We will review the recent advancements and discuss

  14. Rare earth element and neodymium isotope tracing of element input and past ocean circulation. Study from north and south pacific seawater and sediments

    Energy Technology Data Exchange (ETDEWEB)

    Froellje, Henning

    2016-08-09

    Ocean circulation and cycling of trace elements within the oceanic water column is of great significance for modern and past climates. The global overturning circulation is responsible for the distribution of water masses, heat and particulate and dissolved compounds, while biological and chemical processes, such as primary productivity or particle scavenging, control the cycling of nutrients and trace elements in the ocean, and ultimately influence the ocean-atmosphere exchange of carbon. Rare earth elements (REE) and neodymium (Nd) isotopes are widely used as tracers for lithogenic element fluxes and modern and past ocean circulation and water mass mixing. The use of Nd isotopes in paleoceanographic investigations is based on the precise knowledge of processes involved in REE cycling and of the modern oceanic Nd isotope distribution. The Pacific is the largest of the world oceans, but it is highly underrepresented in present-day and past seawater Nd isotope and REE investigations compared to the Atlantic Ocean. In this study, Nd isotopes and REEs are analysed in North Pacific seawater (chapter 2) and sediment samples from the South Pacific (chapters 3-5) to contribute to a better understanding of sources and cycling of REEs and Nd isotopes in present-day seawater and to investigate past water mass mixing and circulation changes during the last glacial termination and throughout the last glacial-interglacial cycle. Neodymium isotopes in seawater and sedimentary archives (fossil fish teeth and debris, foraminifera, ferromanganese oxides, lithogenic particles) were analysed using multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS), and REE concentrations were analysed using isotope dilution ICP-MS. Results from combined analysis of REEs, and Nd and radium isotopes from North Pacific seawater (coastal seawaters of the Hawaiian Island of Oahu and seawater from the offshore Hawaii Ocean Time-series Station ALOHA) show a clear influence of the

  15. Morphodynamics of the Pacific and Caribbean deltas of Colombia, South America

    Science.gov (United States)

    Restrepo, Juan D.; López, Sergio A.

    2008-02-01

    This paper analyzes the physical factors controlling the recent morphology of major deltas along the Pacific and Caribbean coasts of Colombia. The study considers the fluvial, coastal, and oceanographic contributions to changes in delta morphology and uses different approaches, including (1) remote sensing techniques; (2) time series analysis of river discharge, sea level, wave climate and tidal variability; (3) analysis of the relationship between monthly mean sea level anomalies near the deltas related to the El Niño Southern Oscillation (ENSO); (4) development of a database of key physical variables; (5) series of correlation calculations to examine which environmental factors control delta morphology; (6) analysis of shoreline changes for the 1986-2000 yr-period; and (7) classification of each delta system based on the relationship between water and sediment discharges and wave and tidal energies. Overall, Colombian deltas are built under destructive physical conditions. The Pacific deltas, San Juan, Mira, and Patía, are tide-influenced deltas although they exhibit definite characteristics of wave-dominated systems such as the presence of barriers and beach ridges. Also, these deltas exhibit the highest marine energy conditions of all Colombian deltas (marine power values between 9.1 and 11.6) due to the interplay of (1) moderate wave conditions as a result of the effect of swells from the SW with a significant height varying from 1.7 in the San Juan delta to 3.0 m and 3.1 m in the Mira and Patía deltas, respectively; (2) meso-tidal ranges; (3) steep subaqueous profiles; (4) low attenuation indexes of deep-water waves; and (5) strong oceanographic manifestations associated with the ENSO, causing regional sea level rises of 20-44 cm during El Niño events. The Caribbean deltas, Magdalena, Sinú and to a lesser extent, the Atrato, are wave-influenced deltas. The Magdalena, with deep and nearshore wave power values of 45 × 10 6 erg s -1 and 35 × 10 6 erg s -1

  16. Biomass Carbon in the South Mexican Pacific Coast: Exploring Mangrove Potential to REDD+ Mechanisms

    Science.gov (United States)

    Bejarano, M.; Amezcua-Torrijos, I.

    2014-12-01

    Mangroves have the highest carbon stocks amongst tropical forests. In Mexico, however, little is known about their potential to mitigate climate change. In this work, we estimated biomass carbon stocks in the Southern Mexican Pacific Coast (~69,000 ha). We quantified above and belowground biomass carbon stocks at (1) the regional scale along two environmental strata (i.e. dry and wet), and (2) at the local scale along three geomorphological types of mangroves (i.e. fringe, estuarine and basin). Regional strata were defined using intensity and influence of rivers and, the mean annual precipitation and evapotranspiration ratio (i.e., wet dry). By lowering the stressing environmental conditions (e.g., low salinity and high sediment accumulation), we expected the highest stocks in mangroves growing in wet and estuarine strata at the regional scale and local scale, respectively. Quantifications were carried out in sixty-six sites chosen through stratified randomized design in which six strata were obtained by a full combination of regional and local strata. In all strata, aboveground carbon represents 64-67% of total carbon. Total biomass carbon was higher in wet than dry stratum (W: 87.3 ± 6.9, D: 47.0 ± 5.0, pREDD+ mechanisms could be implemented due to (1) their carbon stocks, and (2) their highest deforestation threat in the region as a result of commercial agriculture. Strategies for conservation and enhancement of carbon stocks in these mangroves require strengthened links between carbon and economic benefits that ecosystems provide.

  17. Hindcast of the 2009 South Pacific tsunami - validation of GIS methodologies for local vulnerability and risk assessment in American Samoa

    Science.gov (United States)

    Harbitz, C. B.; Sverdrup-Thygeson, K.; Kaiser, G.; Swarny, R.; Gruenburg, L.; Glimsdal, S.; Løvholt, F.; McAdoo, B. G.; Frauenfelder, R.

    2010-12-01

    the location of the population at a given time of the day, and the mortality is a function of flow depth and building vulnerability. Normally a certain tsunami scenario with a corresponding return period is applied for vulnerability and risk assessments. However, in this study the maximum flow depth was obtained by back modeling the 2009 South Pacific earthquake and tsunami, aiming at validating the GIS model approach for building vulnerability and mortality only. Our model successfully estimated the degree of mortality resulting from this tsunami, based on comparisons with the observed deaths.

  18. Picoplankton diversity in the South-East Pacific Ocean from cultures

    Directory of Open Access Journals (Sweden)

    F. Le Gall

    2008-02-01

    Full Text Available In late 2004, the BIOSOPE cruise sailed between the equatorial influenced waters off the Marquesas Islands and the nutrient enriched waters of the Chilean upwelling. Along the way, it explored the Southeast Pacific gyre centred around Easter Island, which is probably the most oligotrophic oceanic region on earth. During this cruise, we undertook a vigorous effort to isolate novel photosynthetic picoplanktonic eukaryotes. Two strategies were attempted on board: enrichment of filtered samples with culture medium and sorting of specific populations by flow cytometry based on size and chlorophyll fluorescence. Over 1900 pre-cultures were started and then further purified by flow cytometry, serial dilution or pipette isolation to yield a total of 212 strains. These strains were characterized morphologically and for more than 50% of them, genetically, through partial sequencing of the 18 S rRNA gene.

    Among the characterized strains, the largest number belongs to stramenopiles (Heterokontophyta with a record of 38 strains belonging to the species Pelagomonas calceolata (Pelagophyceae. Strains from the recently described genera Bolidomonas and Florenciella have been re-isolated for the first time since their description. Two other abundant groups are the Chlorophyta, especially Prasinophyceae, and the Haptophyta, especially the genera Phaeocystis and Emiliania. A limited number of heterotrophic flagellates have also been isolated, all of them belonging to groups containing known species. Finally, over a dozen of unicellular cyanobacterial Synechococcus strains have been obtained, some forming unusual short chains.

    Overall our strategy was quite successful since it allowed us to isolate a large number of picoplankton strains. Still it failed in two respects. First, apparently very few novel taxa have been obtained. One set of strains is related to Prasinoderma coloniale (Prasinococcales

  19. 77 FR 45591 - Pacific Fishery Management Council; Public Meeting

    Science.gov (United States)

    2012-08-01

    ...-XC141 Pacific Fishery Management Council; Public Meeting AGENCY: National Marine Fisheries Service (NMFS...: The Pacific Fishery Management Council's (Pacific Council) Ad Hoc South of Humbug Pacific Halibut..., monitoring, and allocation history of Pacific halibut in the area south of Humbug Mt. DATES: The conference...

  20. Short- and medium-chain chlorinated paraffins in air and soil of subtropical terrestrial environment in the pearl river delta, South China: distribution, composition, atmospheric deposition fluxes, and environmental fate.

    Science.gov (United States)

    Wang, Yan; Li, Jun; Cheng, Zhineng; Li, Qilu; Pan, Xiaohui; Zhang, Ruijie; Liu, Di; Luo, Chunling; Liu, Xiang; Katsoyiannis, Athanasios; Zhang, Gan

    2013-03-19

    Research on the environmental fate of short- and medium-chain chlorinated paraffins (SCCPs and MCCPs) in highly industrialized subtropical areas is still scarce. Air, soil, and atmospheric deposition process in the Pearl River Delta of South China were investigated, and the average SCCP and MCCP concentrations were 5.2 μg/sampler (17.69 ng/m(3)) and 4.1 μg/sampler for passive air samples, 18.3 and 59.3 ng/g for soil samples, and 5.0 and 5.3 μg/(m(2)d) for deposition samples, respectively. Influenced by primary sources and the properties of chlorinated paraffins (CPs), a gradient trend of concentrations and a fractionation of composition from more to less industrialized areas were discovered. Intense seasonal variations with high levels in summer air and winter deposition samples indicated that the air and deposition CP levels were controlled mainly by the vapor and particle phase, respectively. Complex environmental processes like volatilization and fractionation resulted in different CP profiles in different environment matrixes and sampling locations, with C(10-11) C(l6-7) and C(14) C(l6-7), C(10-12) C(l6-7) and C(14) C(l6-8), and C(11-12) C(l6-8) and C(14) C(l7-8) dominating in air, soil, and atmospheric deposition, respectively. Shorter-chain and less chlorinated congeners were enriched in air in the less industrialized areas, while longer-chain and higher chlorinated congeners were concentrated in soil in the more industrialized areas. This is suggesting that the gaseous transport of CPs is the dominant mechanism responsible for the higher concentrations of lighter and likely more mobile CPs in the rural areas.

  1. Tropospheric ozone climatology at two Southern Hemisphere tropical/subtropical sites, (Reunion Island and Irene, South Africa from ozonesondes, LIDAR, and in situ aircraft measurements

    Directory of Open Access Journals (Sweden)

    G. Clain

    2009-03-01

    Full Text Available This paper presents a climatology and trends of tropospheric ozone in the Southwestern Indian Ocean (Reunion Island and South Africa (Irene and Johannesburg. This study is based on a multi-instrumental dataset: PTU-O3 ozonesondes, DIAL LIDAR and MOZAIC airborne instrumentation.

    The seasonal profiles of tropospheric ozone at Reunion Island have been calculated from two different data sets: ozonesondes and LIDAR. The two climatological profiles are similar, except in austral summer when the LIDAR profiles show greater values in the free troposphere, and in the upper troposphere when the LIDAR profiles show lower values during all seasons. These results show that the climatological value of LIDAR profiles must be discussed with care since LIDAR measurements can be performed only under clear sky conditions, and the upper limit of the profile depends on the signal strength.

    In addition, linear trends have been calculated from ozonesonde data at Reunion and Irene. Considering the whole tropospheric column, the trend is slightly positive for Reunion, and more clearly positive for Irene. Trend calculations have also been made separating the troposphere into three layers, and separating the dataset into seasons. Results show that the positive trend for Irene is governed by the lower layer that is affected by industrial pollution and biomass burning. On the contrary, for Reunion Island, the strongest trends are observed in the upper troposphere, and in winter when stratosphere-troposphere exchange is more frequently expected.

  2. Plastid 16S rRNA gene diversity among eukaryotic picophytoplankton sorted by flow cytometry from the South Pacific Ocean.

    Directory of Open Access Journals (Sweden)

    Xiao Li Shi

    Full Text Available The genetic diversity of photosynthetic picoeukaryotes was investigated in the South East Pacific Ocean. Genetic libraries of the plastid 16S rRNA gene were constructed on picoeukaryote populations sorted by flow cytometry, using two different primer sets, OXY107F/OXY1313R commonly used to amplify oxygenic organisms, and PLA491F/OXY1313R, biased towards plastids of marine algae. Surprisingly, the two sets revealed quite different photosynthetic picoeukaryote diversity patterns, which were moreover different from what we previously reported using the 18S rRNA nuclear gene as a marker. The first 16S primer set revealed many sequences related to Pelagophyceae and Dictyochophyceae, the second 16S primer set was heavily biased toward Prymnesiophyceae, while 18S sequences were dominated by Prasinophyceae, Chrysophyceae and Haptophyta. Primer mismatches with major algal lineages is probably one reason behind this discrepancy. However, other reasons, such as DNA accessibility or gene copy numbers, may be also critical. Based on plastid 16S rRNA gene sequences, the structure of photosynthetic picoeukaryotes varied along the BIOSOPE transect vertically and horizontally. In oligotrophic regions, Pelagophyceae, Chrysophyceae, and Prymnesiophyceae dominated. Pelagophyceae were prevalent at the DCM depth and Chrysophyceae at the surface. In mesotrophic regions Pelagophyceae were still important but Chlorophyta contribution increased. Phylogenetic analysis revealed a new clade of Prasinophyceae (clade 16S-IX, which seems to be restricted to hyper-oligotrophic stations. Our data suggest that a single gene marker, even as widely used as 18S rRNA, provides a biased view of eukaryotic communities and that the use of several markers is necessary to obtain a complete image.

  3. Developing Spatial Management Options for the Protection of Vulnerable Marine Ecosystems in the South Pacific Ocean Region.

    Science.gov (United States)

    Rowden, A. A.; Lundquist, C. J.; Clark, M. R.; Anderson, O. F.; Guinotte, J. M.; Baird, S. J.; Roux, M. J.; Wadhwa, S.

    2016-02-01

    The South Pacific Regional Fisheries Management Organisation (SPRFMO) Convention includes specific provisions to protect vulnerable marine ecosystems (VMEs). The SPRFMO Commission has determined that the interim measures put in place to protect VMEs would be replaced by an improved system of fishable and closed areas. These closures would effectively represent a preliminary spatial management plan, whereby conservation and management measures are implemented that will result in sustainable fisheries and benthic protection. We used the conservation planning tool Zonation to develop spatial management options that balance the protection of VMEs with utilisation of high value areas for fishing. Input data included habitat suitability maps, and uncertainties associated with these model predictions, for eleven VME indicator taxa (4 Scleractinian coral species; 3 other cnidarian groups (Family Stylasteridae, Order Antipatharia, Order Pennatulacea; 2 classes of sponges (Demospongiae, Hexactinellidae), and 2 echninoderm groups (Crinoidea and Brisingida)) at bathyal depths across the entire SPRFMO area (divided into 1 km2 grid cells); New Zealand fishing catch data (for two different time periods and trawl types); naturalness (represented by proxy variable using the number of trawl tows); and a bioregionalisation scheme. Running various scenario models for spatial planning allowed for the cost to fishing to be determined, in terms of the amount of the trawl catch footprint lost if high priority areas for VME indicator taxa are protected. Generally, the cost to fishing was low given the relatively high proportion of suitable habitat for VME indicator taxa protected. The main outcome of the present study is a demonstration of the practical utility of using available data, including modelled data, and the Zonation conservation planning software tool to develop options for the spatial management of the SPRFMO area.

  4. Gross community production and metabolic balance in the South Pacific Gyre, using a non intrusive bio-optical method

    Directory of Open Access Journals (Sweden)

    H. Claustre

    2008-03-01

    Full Text Available The very clear waters of the South Pacific Gyre likely constitute an end-member of oligotrophic conditions which remain essentially unknown with respect to its impact on carbon fixation and exportation. We describe a non-intrusive bio-optical method to quantify the various terms of a production budget (Gross community production, community losses, net community production in this area. This method is based on the analysis of the diel cycle in Particulate Organic Carbon (POC, derived from high frequency measurements of the particle attenuation coefficient cp. We report very high integrated rates of Gross Community Production within the euphotic layer (average of 846±484 mg C m−2 d−1 for 17 stations that are far above any rates determined using incubation techniques for such areas. Furthermore we show that the daily production of POC is essentially balanced by the losses so that the system cannot be considered as net heterotrophic. Our results thus agree well with geochemical methods, but not with incubation studies based on oxygen methods. We stress to the important role of deep layers, below the euphotic layer, in contributing to carbon fixation when incident irradiance at the ocean surface is high (absence of cloud coverage. These deep layers, not considered up to know, might fuel part of the heterotrophic processes in the upper layer, including through dissolved organic carbon. We further demonstrate that, in these extremely clear and stratified waters, integrated gross community production is proportional to the POC content and surface irradiance via an efficiency index ψ GCP*, the water column cross section for Gross Community Production. We finally discuss our results in the context of the role of oligotrophic gyre in the global carbon budget and of the possibility of using optical proxies from space for the development of growth community rather than primary production

  5. Exploring Genomic Diversity Using Metagenomics of Deep-Sea Subsurface Microbes from the Louisville Seamount and the South Pacific Gyre

    Science.gov (United States)

    Tully, B. J.; Sylvan, J. B.; Heidelberg, J. F.; Huber, J. A.

    2014-12-01

    There are many limitations involved with sampling microbial diversity from deep-sea subsurface environments, ranging from physical sample collection, low microbial biomass, culturing at in situ conditions, and inefficient nucleic acid extractions. As such, we are continually modifying our methods to obtain better results and expanding what we know about microbes in these environments. Here we present analysis of metagenomes sequences from samples collected from 120 m within the Louisville Seamount and from the top 5-10cm of the sediment in the center of the south Pacific gyre (SPG). Both systems are low biomass with ~102 and ~104 cells per cm3 for Louisville Seamount samples analyzed and the SPG sediment, respectively. The Louisville Seamount represents the first in situ subseafloor basalt and the SPG sediments represent the first in situ low biomass sediment microbial metagenomes. Both of these environments, subseafloor basalt and sediments underlying oligotrophic ocean gyres, represent large provinces of the seafloor environment that remain understudied. Despite the low biomass and DNA generated from these samples, we have generated 16 near complete genomes (5 from Louisville and 11 from the SPG) from the two metagenomic datasets. These genomes are estimated to be between 51-100% complete and span a range of phylogenetic groups, including the Proteobacteria, Actinobacteria, Firmicutes, Chloroflexi, and unclassified bacterial groups. With these genomes, we have assessed potential functional capabilities of these organisms and performed a comparative analysis between the environmental genomes and previously sequenced relatives to determine possible adaptations that may elucidate survival mechanisms for these low energy environments. These methods illustrate a baseline analysis that can be applied to future metagenomic deep-sea subsurface datasets and will help to further our understanding of microbiology within these environments.

  6. Does herbivorous fish protection really improve coral reef resilience? A case study from new caledonia (South Pacific.

    Directory of Open Access Journals (Sweden)

    Laure Carassou

    Full Text Available Parts of coral reefs from New Caledonia (South Pacific were registered at the UNESCO World Heritage list in 2008. Management strategies aiming at preserving the exceptional ecological value of these reefs in the context of climate change are currently being considered. This study evaluates the appropriateness of an exclusive fishing ban of herbivorous fish as a strategy to enhance coral reef resilience to hurricanes and bleaching in the UNESCO-registered areas of New Caledonia. A two-phase approach was developed: 1 coral, macroalgal, and herbivorous fish communities were examined in four biotopes from 14 reefs submitted to different fishing pressures in New Caledonia, and 2 results from these analyses were challenged in the context of a global synthesis of the relationship between herbivorous fish protection, coral recovery and relative macroalgal development after hurricanes and bleaching. Analyses of New Caledonia data indicated that 1 current fishing pressure only slightly affected herbivorous fish communities in the country, and 2 coral and macroalgal covers remained unrelated, and macroalgal cover was not related to the biomass, density or diversity of macroalgae feeders, whatever the biotope or level of fishing pressure considered. At a global scale, we found no relationship between reef protection status, coral recovery and relative macroalgal development after major climatic events. These results suggest that an exclusive protection of herbivorous fish in New Caledonia is unlikely to improve coral reef resilience to large-scale climatic disturbances, especially in the lightly fished UNESCO-registered areas. More efforts towards the survey and regulation of major chronic stress factors such as mining are rather recommended. In the most heavily fished areas of the country, carnivorous fish and large targeted herbivores may however be monitored as part of a precautionary approach.

  7. Large multicellular filamentous bacteria under the oxygen minimum zone of the eastern South Pacific: a forgotten biosphere

    Science.gov (United States)

    Gallardo, Victor Ariel; Espinoza, Carola

    2007-09-01

    In the soft reduced sediments of the continental shelf, below the oxygen minimum zone (OMZ) of the eastern South Pacific (ESP), peculiar microbial communities have been disclosed which include a variety of large prokaryotes, protists and small metazoans. Dominant among the prokaryotes are large multi-cellular filamentous bacteria which, according to their size range, are roughly divided into megabacteria and macrobacteria. The former group is made up of a few species of Gamma Proteobacteria of the genera Thioploca and Beggiatoa and the second group includes a diversity of phenotypes. Protists include ciliates, flagellates, and foraminifers and the metazoans are mostly nematodes and small polychaetes. A significant similarity has been found in the exploitation of the area/volume relationship among these large bacteria and their fossil analog forms as described from pre-Cambrian rocks. For the same reason, the latter have mostly been referred to as algae or cyanobacteria in the literature. The presence of these seemingly ancient bacteria in the sediments of the oxygen minimum zones of the ESP, one of the most productive but also ecologically most inefficient marine ecosystems of the world, suggests that such setting must have prevailed throughout the geological history of the planet allowing for their survival and further that it might be considered an analog of Proterozoic ocean conditions. These non-cyanobacterial communities offer an alternative hypothesis to students of the evolution of life on Earth and may be of special interest to astrobiologists looking for life or traces of life in terrestrial or extraterrestrial environments since these do not necessarily imply a photosynthesis-based metabolism.

  8. Population structure of humpback whales in the western and central South Pacific Ocean as determined by vocal exchange among populations.

    Science.gov (United States)

    Garland, Ellen C; Goldizen, Anne W; Lilley, Matthew S; Rekdahl, Melinda L; Garrigue, Claire; Constantine, Rochelle; Hauser, Nan Daeschler; Poole, M Michael; Robbins, Jooke; Noad, Michael J

    2015-08-01

    For cetaceans, population structure is traditionally determined by molecular genetics or photographically identified individuals. Acoustic data, however, has provided information on movement and population structure with less effort and cost than traditional methods in an array of taxa. Male humpback whales (Megaptera novaeangliae) produce a continually evolving vocal sexual display, or song, that is similar among all males in a population. The rapid cultural transmission (the transfer of information or behavior between conspecifics through social learning) of different versions of this display between distinct but interconnected populations in the western and central South Pacific region presents a unique way to investigate population structure based on the movement dynamics of a song (acoustic) display. Using 11 years of data, we investigated an acoustically based population structure for the region by comparing stereotyped song sequences among populations and years. We used the Levenshtein distance technique to group previously defined populations into (vocally based) clusters based on the overall similarity of their song display in space and time. We identified the following distinct vocal clusters: western cluster, 1 population off eastern Australia; central cluster, populations around New Caledonia, Tonga, and American Samoa; and eastern region, either a single cluster or 2 clusters, one around the Cook Islands and the other off French Polynesia. These results are consistent with the hypothesis that each breeding aggregation represents a distinct population (each occupied a single, terminal node) in a metapopulation, similar to the current understanding of population structure based on genetic and photo-identification studies. However, the central vocal cluster had higher levels of song-sharing among populations than the other clusters, indicating that levels of vocal connectivity varied within the region. Our results demonstrate the utility and value of

  9. Geochemical response of a closed-lake basin to 20th century recurring droughts/wet intervals in the subtropical Pampean Plains of South America

    Directory of Open Access Journals (Sweden)

    Daniel ARIZTEGUI

    2004-02-01

    Full Text Available Laguna Mar Chiquita is a highly variable closed saline lake located in the Pampean Plains of central Argentina. Presently is the largest saline lake in South America (∼ 6,000 km2 and also one of the largest in the world. During the 20th century the hydrological balance of the region was characterized by contrasting scenarios. Well-defined wet or dry climatic phases had ruled the lake level fluctuations and the rivers discharge, mainly controlling the geochemical composition of sediments. Sediments accumulated during positive hydrological balances (i.e., high lake level are mainly composed of allogenic mineral due to higher riverine inputs into the lake. This fluvial-dominated lake phases are recorded as sediments enriched in Al2O3, SiO2, K2O, Fe2O3 and TiO2 and in trace elements such as Co, Cr, Cs, Rb, Sc, Hf, Ta, Th as well as rare earth elements (REE. Sediments accumulated during dry phases (i.e., low lake levels and high salinity are evaporite mineral-rich with elevated concentrations of CaO, MnO, MgO, and P2O5. High contents of As and U are probably due to a co-precitation during high evaporative phases. The calibration of the sediment chemical composition of Laguna Mar Chiquita to well-defined water-level fluctuations of the 20th century shows that elemental geochemistry can be a useful proxy to study former lake-water fluctuations. It may further provide a comparative model to evaluate past environmental conditions in other saline lacustrine basins.

  10. Temperature profile and other data collected using CTD, BT, and XBT casts from NOAA Ship RESEARCHER and other platforms in the North/South Pacific Ocean and North/South Atlantic Ocean from 1973-01-13 to 1983-03-14 (NODC Accession 8300091)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile and other data were collected using CTD, BT, and XBT casts from NOAA Ship RESEARCHER and other platforms in the North/South Pacific Ocean and...

  11. Physical, wind wave spectra, and other data from meteorological sensors, moored buoy casts, thermistors, and accelerometers in fixed locations in the Gulf of Mexico, South Pacific Ocean, Coastal Waters of Western U.S., Great Lakes, North American Coastline-North, and North American Coastline-South from 01 January 2001 to 31 January 2001 (NODC Accession 0000408)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Physical, wind wave spectra, and other data were collected from fixed platforms in the Gulf of Mexico, South Pacific Ocean, Coastal Waters of Western U.S., Great...

  12. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2014-12-30 to 2015-07-01 (NCEI Accession 0144343)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144343 includes Surface underway data collected from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60...

  13. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2011-01-02 to 2011-12-18 (NCEI Accession 0148767)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0148767 includes Surface underway data collected from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60...

  14. Partial pressure (or fugacity) of carbon dioxide, dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, Barometric pressure sensor and other instruments from NOAA Ship RONALD H. BROWN in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2005-01-11 to 2005-02-24 (NODC Accession 0108153)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0108153 includes discrete sample and profile data collected from NOAA Ship RONALD H. BROWN in the South Atlantic Ocean, South Pacific Ocean and...

  15. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2002-12-29 to 2003-11-30 (NCEI Accession 0144351)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144351 includes Surface underway data collected from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60...

  16. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2007-01-02 to 2007-12-20 (NCEI Accession 0148773)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0148773 includes Surface underway data collected from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60...

  17. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2007-12-30 to 2008-10-28 (NCEI Accession 0144348)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144348 includes Surface underway data collected from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60...

  18. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2011-12-30 to 2012-12-24 (NCEI Accession 0144349)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144349 includes Surface underway data collected from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60...

  19. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2014-01-01 to 2014-12-20 (NCEI Accession 0145200)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0145200 includes Surface underway data collected from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60...

  20. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2007-01-02 to 2007-12-22 (NCEI Accession 0144528)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144528 includes Surface underway data collected from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60...

  1. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2011-01-02 to 2011-12-19 (NCEI Accession 0144354)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144354 includes Surface underway data collected from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60...

  2. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2002-03-23 to 2002-12-23 (NCEI Accession 0148766)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0148766 includes Surface underway data collected from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60...

  3. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2006-01-01 to 2006-12-27 (NCEI Accession 0144535)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144535 includes Surface underway data collected from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60...

  4. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2013-12-31 to 2014-12-20 (NCEI Accession 0144532)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144532 includes Surface underway data collected from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60...

  5. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2002-03-07 to 2002-12-23 (NCEI Accession 0144356)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144356 includes Surface underway data collected from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60...

  6. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2011-12-30 to 2012-12-23 (NCEI Accession 0148774)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0148774 includes Surface underway data collected from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60...

  7. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2006-01-02 to 2006-12-26 (NCEI Accession 0148764)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0148764 includes Surface underway data collected from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60...

  8. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2010-01-01 to 2011-12-19 (NCEI Accession 0148765)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0148765 includes Surface underway data collected from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60...

  9. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2003-01-01 to 2003-12-29 (NCEI Accession 0148770)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0148770 includes Surface underway data collected from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60...

  10. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2007-12-31 to 2008-10-27 (NCEI Accession 0148763)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0148763 includes Surface underway data collected from LAURENCE M. GOULD in the South Atlantic Ocean, South Pacific Ocean and Southern Oceans (> 60...

  11. Variation of the Tropical Upper-tropospheric Trough and Its Linkage to the Asian-Pacific-North American Summer Climate

    Science.gov (United States)

    Deng, Kaiqiang; Yang, Song

    2016-04-01

    The tropical upper-tropospheric trough (TUTT) is one of the most prominent features in Northern Hemisphere (NH) summer, which peaks at 200-150 hPa in July and August. It is found that the TUTT varies largely from year to year, which indicates that the TUTT may exert great effects on the NH summer climate. In order to explore the causes that lead to the interannual variations of the TUTT, an area-weighted empirical orthogonal function decomposition analysis was applied to. The first mode reflects the northeastward-southwestward displacement of the TUTT, which is significantly related to the planetary wave originating from the Indo-western Pacific during a developing La Niña. The second mode presents the intensity change of the TUTT, which is attributed to the enhanced convection over the central Pacific where the anomalous warming sea surface temperature is appearing. The third mode shows the northwestward-southeastward displacement of the TUTT, which is correlated well with the north-south direction shift of east Asian westerly jet. Anomalous warming over the midlatitudes and cooling over the subtropics suggests a decreased meridional temperature gradient, which results in the northward displacement of westerly jet. The variations of TUTT's location and strength have distinct effects on the variation of South Asian high, the northwestern Pacific subtropical high, and the Mexican high, which subsequently modulate the climate anomalies in different regions.

  12. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Barometric pressure sensor, Carbon dioxide (CO2) gas analyzer and other instruments from ROGER REVELLE in the South Pacific Ocean and Southern Oceans from 2005-01-06 to 2005-02-19 (NCEI Accession 0144243)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144243 includes Surface underway data collected from ROGER REVELLE in the South Pacific Ocean and Southern Oceans (> 60 degrees South) from...

  13. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Barometric pressure sensor, Carbon dioxide (CO2) gas analyzer and other instruments from ROGER REVELLE in the Indian Ocean, South Pacific Ocean and others from 2007-02-04 to 2007-03-16 (NCEI Accession 0144252)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144252 includes Surface underway data collected from ROGER REVELLE in the Indian Ocean, South Pacific Ocean, Southern Oceans (> 60 degrees South)...

  14. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from ROGER REVELLE in the South Pacific Ocean and Southern Oceans from 2005-01-09 to 2005-02-19 (NODC Accession 0108095)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0108095 includes discrete sample and profile data collected from ROGER REVELLE in the South Pacific Ocean and Southern Oceans (> 60 degrees South)...

  15. Clustering analysis of western North Pacific Tropical Cyclone tracks using the Self Organizing Map

    Science.gov (United States)

    Kim, H.; Seo, K.

    2013-12-01

    A cluster analysis using Self Organizing Map (SOM) is used to characterize tropical cyclone (TC) tracks over the western North Pacific. A False Discovery Rate (FDR) method is used to objectively determine an optimum cluster number. For 620 TC tracks over the WNP from June-October during 1979-2010, the five clusters for TC tracks are selected. These can further be categorized into three major patterns: straight-moving track, recurving track, and quasi-random pattern. Each pattern is characterized by land falling regions: near South and East China, East Asia, and off-shore of Japan. In addition, each pattern shows distinctive properties in its traveling distance, lifetime, intensity (mean minimum sea level pressure), and genesis location. It is revealed that these three patterns are associated with the large-scale dynamics such as variability of the western Pacific subtropical high and the Madden-Julian Oscillation. The impacts of El Nino and NAO will be discussed.

  16. Multiple Drivers of Local (Non- Compliance in Community-Based Marine Resource Management: Case Studies from the South Pacific

    Directory of Open Access Journals (Sweden)

    Janne R. Rohe

    2017-05-01

    Full Text Available The outcomes of marine conservation and related management interventions depend to a large extent on people's compliance with these rule systems. In the South Pacific, community-based marine resource management (CBMRM has gained wide recognition as a strategy for the sustainable management of marine resources. In current practice, CBMRM initiatives often build upon customary forms of marine governance, integrating scientific advice and management principles in collaboration with external partners. However, diverse socio-economic developments as well as limited legal mandates can challenge these approaches. Compliance with and effective (legally-backed enforcement of local management strategies constitute a growing challenge for communities—often resulting in considerable impact on the success or failure of CBMRM. Marine management arrangements are highly dynamic over time, and similarly compliance with rule systems tends to change depending on context. Understanding the factors contributing to (non- compliance in a given setting is key to the design and function of adaptive management approaches. Yet, few empirical studies have looked in depth into the dynamics around local (non- compliance with local marine tenure rules under the transforming management arrangements. Using two case studies from Solomon Islands and Fiji, we investigate what drives local (non- compliance with CBMRM and what hinders or supports its effective enforcement. The case studies reveal that non-compliance is mainly driven by: (1 diminishing perceived legitimacy of local rules and rule-makers; (2 increased incentives to break rules due to market access and/ or lack of alternative income; and (3 relatively weak enforcement of local rules (i.e., low perceptions of risk from sanctions for rule-breaking. These drivers do not stand alone but can act together and add up to impair effective management. We further analyze how enforcement of CBMRM is challenged through a range of

  17. Persistent decadal-scale rainfall variability in the tropical South Pacific Convergence Zone through the past six centuries

    OpenAIRE

    Maupin, C. R.; Partin, J. W.; Shen, C.-C.; Quinn, T. M.; Lin, K.; Taylor, F. W.; Banner, J. L.; Thirumalai, K.; Sinclair, D. J.

    2014-01-01

    Modern Pacific decadal variability (PDV) has global impacts; hence records of PDV from the pre-instrumental period are needed to better inform models that are used to project future climate variability. We focus here on reconstructing rainfall in the western tropical Pacific (Solomon Islands; ~ 9.5° S, ~160° E), a region directly influenced by PDV, using cave deposits (stalagmite). A relationship is developed between δ18O variations in the stalagmite and local rainfall am...

  18. Molecular and histological identification of Marteilioides infection in Suminoe Oyster Crassostrea ariakensis, Manila Clam Ruditapes philippinarum and Pacific Oyster Crassostrea gigas on the south coast of Korea.

    Science.gov (United States)

    Limpanont, Yanin; Yanin, Limpanont; Kang, Hyun-Sil; Hong, Hyun-Ki; Jeung, Hee-Do; Kim, Bong-Kyu; Le, Thanh Cuong; Kim, Young-Ok; Choi, Kwang-Sik

    2013-11-01

    The oyster ovarian parasite Marteilioides chungmuensis has been reported from Korea and Japan, damaging the oyster industries. Recently, Marteilioides-like organisms have been identified in other commercially important marine bivalves. In this study, we surveyed Marteilioides infection in the Manila clam Ruditapes philippinarum, Suminoe oyster Crassostrea ariakensis, and Pacific oyster Crassostrea gigas, using histology and Marteilioides-specific small subunit (SSU) rDNA PCR. The SSU rDNA sequence of M. chungmuensis (1716 bp) isolated from C. gigas in Tongyoung bay was 99.9% similar to that of M. chungmuensis reported in Japan. Inclusions of multi-nucleated bodies in the oocytes, typical of Marteilioides infection, were identified for the first time in Suminoe oysters. The SSU rDNA sequence of a Marteilioides-like organism isolated from Suminoe oysters was 99.9% similar to that of M. chungmuensis. Marteilioides sp. was also observed from 7 Manila clams of 1840 individuals examined, and the DNA sequences of which were 98.2% similar to the known sequence of M. chungmuensis. Unlike Marteilioides infection of Pacific oysters, no remarkable pathological symptoms, such as large multiple lumps on the mantle, were observed in infected Suminoe oysters or Manila clams. Distribution of the infected Manila clams, Suminoe oysters and Pacific oysters was limited to small bays on the south coast, suggesting that the southern coast is the enzootic area of Marteilioides infection. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Non-colonial coral macro-borers as indicators of coral reef status in the south Pacific of Costa Rica

    Directory of Open Access Journals (Sweden)

    A.C Fonseca E

    2006-03-01

    Full Text Available Coral reef status was surveyed in three south Pacific coral reefs of Costa Rica, one in Caño Island and two in Golfo Dulce, and the density, richness and distribution of non-colonial macro borers (>1 mmwas determined in dead and live coral fragments from these reefs. Based upon traditional indicators of degradation such as high particulate suspended matter and low live coral cover, the reefs at Caño Island are in better condition than those at Golfo Dulce. Reef degradation in Golfo Dulce is mainly due to high loads of terrestrial sediments as a consequence of watersheds deforestation. In this study, 36 coral boring species are reported for the eastern Pacific. At the family level, there is high endemism (10% and greater affinity with the Indo-Pacific (34%, as compared with the eastern Atlantic and Mediterranean (29% and western Atlantic and Caribbean (27%. The dominant non-colonial macro boring families at the study reefs are mytilid bivalves, eunicid polychaetes and aspidosiphonid sipunculans, with the bivalves considered the main internal bioeroders due to their greater body size and abundances. The level of mortality of the coral colonies and the general level of reef degradation influenced the composition of non-colonial macro-borers. Diversity and total macro-borer density, especially aspidosiphonid density, is higher in corals with greates dead than live cover. In the healthiest coral colonies (less than 50% of partial mortality, mytilids domination, macro-borer diversity and total density, is higher in Golfo Dulce, where reefs are more degraded. In the most affected coral colonies (more than 50% dead, macro-borers total density, especially aspidosiphonids density, is higher, of the healthiest reef of this study, Platanillo. Bivalve relative abundance increases and sipunculan relative abundance decreases with increasing site degradation. In conclusion bioeroder variables can also be used as reef health indicators. Rev. Biol. Trop. 54 (1

  20. Anthopleura radians, a new species of sea anemone (Cnidaria: Actiniaria: Actiniidae from northern Chile, with comments on other species of the genus from the South Pacific Ocean

    Directory of Open Access Journals (Sweden)

    Carlos Spano

    2017-05-01

    Full Text Available A new species of sea anemone, Anthopleura radians n. sp., is described from the intertidal zone of northern Chile and the taxonomic status of the other Anthopleura species from the South Pacific are discussed. A. radians n. sp. is characterized by a yellow-whitish and brown checkerboard-like pattern on the oral disc, adhesive verrucae along the entire column and a series of marginal projections, each bearing a brightly-colored acrorhagus on the oral surface. This is the seventh species of Anthopleura described from the South Pacific Ocean; each one distinguished by a particular combination of differences related to their coloration pattern, presence of zooxanthellae, cnidae, and mode of reproduction. Some of these species have not been reported since their original description and thus require to be taxonomically validated. A. hermaphroditica and A. aureoradiata are synonyms considering the lack of differences seen between live specimens, museum collections and published records. A. radians could also be a junior synonym of A. minima, however, no type material was found for testing this hypothesis. Furthermore, it is crucial to designate neotypes for A. inconspicua, A. rosea and A. minima since there are no name-bearing types reported for these species.

  1. Variation Characteristics of Rainfall in the Pre-Flood Season of South China and Its Correlation with Sea Surface Temperature of Pacific

    Directory of Open Access Journals (Sweden)

    Suxiang Yao

    2015-12-01

    Full Text Available The characteristics of rainfall variation in the pre-flood season of South China (PFSSC and its correlation with the sea surface temperature (SST of the Pacific are studied in this paper. The results show that in the last 50 years, rainfall in PFSSC clearly has interannual and interdecadal oscillations, primarily in the 4a and 8a cycles. Interannual correlation analysis indicate that the rainfall in PFSSC displays a significantly negative correlation with the SST of the warm pool region in January–March and April–June. The interdecadal correlation analysis reveals that the rainfall in PFSSC is negatively correlated to the SST of the warm pool region, but has a significant positive interdecadal correlation with the Middle Eastern Pacific Ocean. For NINO1 + 2 and NINO3 regions, when the background ocean temperature is warm, the SST is significantly positively correlated to the rainfall in PFSSC; however, when the background ocean temperature is cold, there is no significant correlation between the two, even the correlation coefficients are negative. For the warm pool region, the SST demonstrates a significantly negative correlation to the rainfall in PFSSC, which is not dependent on the background SST. It is a remarkable fact that under the different SST backgrounds, the interannual variation of SST will bring different atmospheric response, and it is the reason that under the warm SST background, the correlation is more significant between the SST in tropical Pacific and the rainfall in PFSSC. Under the background of global warming, more attention should be given to study the rainfall in PFSSC and its correlation with the SST in the eastern tropical Pacific.

  2. The post-2002 global surface warming slowdown caused by the subtropical Southern Ocean heating acceleration

    Science.gov (United States)

    Oka, A.; Watanabe, M.

    2017-04-01

    The warming rate of global mean surface temperature slowed down during 1998-2012. Previous studies pointed out role of increasing ocean heat uptake during this global warming slowdown, but its mechanism remains under discussion. Our numerical simulations, in which wind stress anomaly in the equatorial Pacific is imposed from reanalysis data, suggest that subsurface warming in the equatorial Pacific took place during initial phase of the global warming slowdown (1998-2002), as previously reported. It is newly clarified that the Ekman transport from tropics to subtropics is enhanced during the later phase of the slowdown (after 2002) and enhanced subtropical Ekman downwelling causes accelerated heat storage below depth of 700 m in the subtropical Southern Ocean, leading to the post-2002 global warming slowdown. Observational data of ocean temperature also support this scenario. This study provides clear evidence that deeper parts of the Southern Ocean play a critical role in the post-2002 warming slowdown.

  3. Regional climate of the subtropical central Andes using high-resolution CMIP5 models—part I: past performance (1980-2005)

    Science.gov (United States)

    Zazulie, Natalia; Rusticucci, Matilde; Raga, Graciela B.

    2017-12-01

    This study assesses the performance of 15 high resolution global climate models (GCMs) over the complex orographic region of the subtropical central Andes from available simulations of the Fifth Coupled Model Intercomparison Project (CMIP5). The simulated past climate (1980-2005) was compared against the Climate Research Unit (CRU) dataset and the ERA-Interim reanalysis, considered as reference datasets, to evaluate regional and seasonal surface temperature and precipitation, as well as sea level pressure and circulation. A good agreement was found between the simulations and the reference datasets for winter precipitation and for temperature over both seasons. Whilst all models correctly reproduce the annual cycle of precipitation, some of them overestimate winter totals. ERA-Interim does not adequately represent summer precipitation over the region, and some of the models analyzed also show the same deficiency. All models correctly reproduce the northward migration of the South Pacific subtropical high during winter, although some of them underestimate the maximum central pressure. During summer, most models fail to show the low level north-south flow parallel to the eastern foothills of the Andes, a feature known as the Low Level Jet. Further analysis of the results of the simulations led to the selection of a sub-set of five CMIP5 GCMs to construct a reduced ensemble. This reduced ensemble is a better representation than the multi-model mean of the 15 GCMs of the past climate at this region and would be recommended for future studies.

  4. Preliminary assessment of the impacts and effects of the South Pacific tsunami of September 2009 in Samoa

    Science.gov (United States)

    Dominey-Howes, D.

    2009-12-01

    The September 2009 tsunami was a regional South Pacific event of enormous significance. Our UNESCO-IOC ITST Samoa survey used a simplified version of a ‘coupled human-environment systems framework’ (Turner et al., 2003) to investigate the impacts and effects of the tsunami in Samoa. Further, the framework allowed us to identify those factors that affected the vulnerability and resilience of the human-environment system before, during and after the tsunami - a global first. Key findings (unprocessed) include: Maximum run-up exceeded 14 metres above sea level Maximum inundation (at right angles to the shore) was approximately 400 metres Maximum inundation with the wave running parallel with the shore (but inland), exceeded 700 metres Buildings sustained varying degrees of damage Damage was correlated with depth of tsunami flow, velocity, condition of foundations, quality of building materials used, quality of workmanship, adherence to the building code and so on Buildings raised even one metre above the surrounding land surface suffered much less damage Plants, trees and mangroves reduced flow velocity and flow depth - leading to greater chances of human survival and lower levels of building damage The tsunami has left a clear and distinguishable geological record in terms of sediments deposited in the coastal landscape The clear sediment layer associated with this tsunami suggests that older (and prehistoric) tsunamis can be identified, helping to answer questions about frequency and magnitude of tsunamis The tsunami caused widespread erosion of the coastal and beach zones but this damage will repair itself naturally and quickly The tsunami has had clear impacts on ecosystems and these are highly variable Ecosystems will repair themselves naturally and are unlikely to preserve long-term impacts It is clear that some plant (tree) species are highly resilient and provided immediate places for safety during the tsunami and resources post-tsunami People of Samoa are

  5. Mineral-Association and Activity of Bacteria and Archaea in the Deep Subsurface South Pacific Gyre Sediment

    Science.gov (United States)

    Steele, J. A.; Dekas, A. E.; Harrison, B. K.; Morono, Y.; Inagaki, F.; Ziebis, W.; Orphan, V. J.

    2012-12-01

    Although the subsurface biosphere is now recognized as an important reservoir of life on our planet, until recently the microbial community beneath open-ocean oligotrophic gyres (making up the majority of the seafloor) has just begun to be studied in detail. IODP Expedition 329 and the KNOX-022RR site survey cruise have taken some of the first steps at characterizing the microbial community beneath the South Pacific Gyre, a region with low organic carbon burial rates (10-8 and 10-10 moles C cm-1 yr-1), deep oxygen penetration (sediments are oxidized to the basement), and low prokaryotic cell counts (106 cells cm-3 to cells cm-3). In these sediments, the dominant fraction of organic carbon may be aggregated or adsorbed to minerals, suggesting that microbes that are able to grow on the minerals may create potential "hotspots" of activity. In this study, we performed magnetic separation on oligotrophic sediment samples and examined the bacterial and archaeal communities using 16S rRNA tag sequencing. To determine if the mineral-associated cells were autotrophic and/or utilizing nitrate, we performed long-term (20 month) incubations with 13CO2 and 15NO3- from sediment taken at depths ~2-70 mbsf beneath the oligotrophic gyre and outside of the oligotrophic gyre (IODP Exp. 329 stations U1368-U1371). Subsequently we used the DNA stain SYBR Green I, and CARD-FISH-NanoSIMS to identify cells which were actively taking up the isotopic label. We then used SEM-EDS to identify the mineral particle composition. Preliminary results found the magnetic fraction in oligotrophic sediment (KNOX-022RR station SPG-5) from 1.2-2.6 mbsf showed a greater diversity of both bacteria and archaea. OTUs from Chloroflexi groups SO85 and SAR202 were dominant in the magnetic fraction. Firmicutes, Bacteroidetes, δ-Proteobacteria, Verrucomicrobia, Deferribacteres, WS3, OP10, and OP1 OTUs were found only in the magnetic fraction. Crenarchaeal OTUs from Marine Benthic Group B and Marine Group I

  6. 'Live more': Study protocol for a community-based lifestyle education program addressing non-communicable diseases in low-literacy areas of the South Pacific.

    Science.gov (United States)

    Kent, L M; Reierson, P; Morton, D P

    2015-12-09

    Non-communicable diseases (NCDs) have reached epidemic proportions in Pacific Island countries. Unhealthy lifestyle is one of the major risk factors and lifestyle interventions have been shown to be efficacious for primary, secondary and early tertiary prevention. However, there is a paucity of evidence regarding effective community-based lifestyle interventions in the Pacific Islands. The Complete Health Improvement Program for high-income countries was contextualised for rural communities with relatively low-literacy rates in low-income countries using the REFLECT delivery approach. This study will assess the effect of this 'Live More' program to reduce participant's NCD risk factors and improve lifestyle behaviours associated with health and wellbeing, in low-literacy communities in countries of the South Pacific. This study is a 6-month cluster-randomised controlled trial of 288 adults (equal proportions of men and women aged 18 years and over) with waist circumference of ≥92 cm for men and ≥80 cm for women in four rural villages in each of Fiji, Vanuatu and Solomon Islands. Participants will permanently reside in their village and be able to prepare their own meals. Two villages will be randomised to the 'Live More' intervention (n = 24) or to control receiving only country specific Ministry of Health literature (n = 24). Intervention participants will meet three times a week in the first month, then once a week for the next two months and once a month for the last three months. Themes covered include: NCDs and their causes; and the benefits of positive lifestyle choices, positive psychology, stress management, forgiveness and self-worth, and how these influence long-term health habits. Outcome assessments at baseline, 30-days, 3-months and 6-months include body mass index, waist circumference, blood lipids, blood pressure and blood glucose. Secondary outcomes include changes in medication and substance use, diet, physical activity, emotional

  7. Shifts of the Subtropical Shelf Front controlled by atmospheric variations

    Science.gov (United States)

    Balcerak, Ernie

    2013-10-01

    In the western South Atlantic, off the coast of South America, a band of cold, fresh, nutrient-rich Sub-Antarctic Shelf Water (SASW) meets warm, salty, nutrient-poor Subtropical Shelf Water (STSW) to form the Subtropical Shelf Front (STSF). This front is the shallow-water expression of the major Brazil-Malvinas Confluence Zone and has moved northward and southward during the Holocene (the past ~12,000 years). Bender et al. reconstruct the latitudinal shifts of the STSF over the past 11,000 calendar-equivalent years using records of oxygen and carbon stable isotope compositions of benthic foraminifera and total organic carbon and calcium carbonate content from a sediment record collected off Uruguay. These measurements serve as proxies for ocean water temperature and nutrient content, which can be used to distinguish the SASW and STSW.

  8. Late Pleistocene glacial fluctuations in Cordillera Oriental, subtropical Andes

    Science.gov (United States)

    Martini, Mateo A.; Kaplan, Michael R.; Strelin, Jorge A.; Astini, Ricardo A.; Schaefer, Joerg M.; Caffee, Marc W.; Schwartz, Roseanne

    2017-09-01

    The behavior of subtropical glaciers during Middle to Late Pleistocene global glacial maxima and abrupt climate change events, specifically in Earth's most arid low-latitude regions, remains an outstanding problem in paleoclimatology. The present-day climate of Cordillera Oriental, in arid northwestern Argentina, is influenced by shifts in subtropical climate systems, including the South American Summer Monsoon. To understand better past glacier-subtropical climates during the global Last Glacial Maximum (LGM, 26.5-19 ka) and other time periods, we combined geomorphic features with forty-two precise 10Be ages on moraine boulders and reconstructed paleo-equilibrium line altitudes (ELA) at Nevado de Chañi (24°S) in the arid subtropical Andes. We found a major glacial expansion at ∼23 ± 1.6 ka, that is, during the global LGM. Additional glacial expansions are observed before the global LGM (at ∼52-39 ka), and after, at 15 ± 0.5 and 12 ± 0.6 ka. The ∼15 ka glacial event was found on both sides of Chañi and the ∼12 ka event is only recorded on the east side. Reconstructed ELAs of the former glaciers exhibit a rise from east to west that resembles the present subtropical climate trajectory from the Atlantic side of the continent; hence, we infer that this climate pattern must have been present in the past. Based on comparison with other low-latitude paleoclimate records, such as those from lakes and caves, we infer that both temperature and precipitation influenced past glacial occurrence in this sector of the arid Andes. Our findings also imply that abrupt deglacial climate events associated with the North Atlantic, specifically curtailed meridional overturning circulation and regional cooling, may have had attendant impacts on low subtropical Southern Hemisphere latitudes, including the climate systems that affect glacial activity around Nevado de Chañi.

  9. Current meter and other data collected using current meter casts from R/V RESEARCHER and R/V CALANUS in the Atlantic and Pacific Ocean as part of the Eastern Pacific Ocean Circulation Study (EPOCS) and Subtropical Atlantic Current Study (STACS), 23 March 1983 - 19 November 1986 (NODC Accession 8700226)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Current meter and other data were collected using current meter casts from R/V RESEARCHER and R/V CALANUS in the Atlantic and Pacific Ocean from March 23, 1983 to...

  10. Wind waves spectra and other data collected using moored buoy in the Great Lakes, Gulf of Mexico, South Pacific and East/West coast of US from 01 June 2000 to 30 June 2000 (NODC Accession 0000217)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Wind wave spectra and other data were collected using moored buoys in the Great lakes, Gulf of Mexico, South Pacific and East/West coast of US from June 01, 2000 to...

  11. Salinity and temperature profile data from XCTD and CTD casts in the North/South Pacific Ocean by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), from 07 January 2002 to 30 March 2003 (NODC Accession 0000860)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Salinity and temperature profile data were collected using XCTD and CTD casts from the R/V MIRAI in the North/South Pacific Ocean from 07 January 2002 to 30 March...

  12. The distribution of lead between sea salt, dust, and lead-rich aerosols in the mid South Pacific Easterlies at American Samoa

    Energy Technology Data Exchange (ETDEWEB)

    Rosman, K.J.R.; Patterson, C.C.; Settle, D.M. (California Inst. of Tech., Pasadena (United States))

    1990-03-20

    Aerosols in the South Pacific Easterlies have been sampled at American Samoa with a cascade impactor and analyzed for Pb, Ba, K, Ca, Sr, and Rb by isotope dilution mass spectrometry using ultraclean procedures. Some 84% of the Pb was found in fine ({le}0.5 {mu}m) aerosols which were collected on the backup filter with an efficiency of only 33%. Sea salt and eroded terrestrial material (dust) containing 6% and < 1% respectively, of the Pb (sea salt indexed by the metals K, Ca, Sr, and Rb and dust indexed by Ba) were collected on early stages of the impactor, although 65% of the dust, because of its larger size, was lost to surfaces of the rain shelter before reaching the impactor. The remaining 10% of the Pb was associated with plant leaf waxes of continental origin which produced Pb and Ba peaks on stage 4 (0.5 {mu}m) of the impactor.

  13. Early manifestations of the Valparaíso’s imaginary. In the context of a porteña culture of the South Pacific

    Directory of Open Access Journals (Sweden)

    Marco Chandía Araya

    2016-07-01

    Full Text Available The poetic imaginary that emerges from the porteña culture of the South Pacific is a product of the imagination that responds to a historic scriptural exercise. We review these manifestations from three moments or sensitivities that build an image of the Valparaiso city-port. The journey tale, the modernist gesture and the naturalistic narrative (all of them appear before a major aesthetic-literary product reveal a way of inhabit the city-port that allows to propose the existence of a culture in conflict with Occident.  The passages of these manifestations cannot be read separately from that poetic of the porteño inhabit, but as part of a discourse of the border that declares against the oblivion and in favor of the historic survival of these city-ports

  14. Comparison of the Carbon System Parameters at the Global CO2 Survey Crossover Locations in the North and South Pacific Ocean, 1990-1996

    Energy Technology Data Exchange (ETDEWEB)

    Feely, Richard A [NOAA, Pacific Marine Environmental Laboratory (PMEL); Lamb, Marilyn F. [NOAA, Pacific Marine Environmental Laboratory (PMEL); Greeley, Dana J. [NOAA, Pacific Marine Environmental Laboratory (PMEL); Wanninkhof, Rik [NOAA, Atlantic Oceanographic and Meteorological Laboratory (AOML)

    1999-10-01

    As a collaborative program to measure global ocean carbon inventories and provide estimates of the anthropogenic carbon dioxide (C02) uptake by the oceans. the National Oceanic and Atmospheric Administration and the U.S. Department of Energy have sponsored the collection of ocean carbon measurements as part of the World Ocean Circulation Experiment and Ocean-Atmosphere Carbon Exchange Study cruises. The cruises discussed here occurred in the North and South Pacific from 1990 through 1996. The carbon parameters from these 30 crossover locations have been compared to ensure that a consistent global data set emerges from the survey cruises. !'he results indicate that for dissolved inorganic carbon. fugacity of C02• and pH. the a~:,rreements at most crossover locations are well within the design specifications for the global CO) survey: whereas. in the case of total alkaliniry. the agreement between crossover locations is not as close.

  15. [Effects of hurricane "Pauline" (1997) on the fauna associated with the plant Eichhornia crassipes in Laguna Coyuca, South Pacific of Mexico].

    Science.gov (United States)

    Román-Contreras, Ramiro; Rocha-Ramírez, Arturo; Cházaro-Olvera, Sergio

    2008-06-01

    Effects of hurricane "Pauline" (1997) on the fauna associated with the plant Eichhornia crassipes in Laguna Coyuca, South Pacific of Mexico. Reports on the effects of hurricanes on marine and coastal environments often deal with coral reefs, but little is known about their effect on the communities associated with the water hyacinth, Eichhornia crassipes. From January 1997 (pre-hurricane) through April 1998 (post-hurricane) we made montly collections of fauna in E. crassipes roots from Laguna Coyuca, Mexico (17 degrees 00' - 16 degrees 54' N, 99 degrees 58'-100 degrees 05' W). The hurricane affected Coyuca on October 9th, 1997 and caused mortalities of that fauna. During the three subsequent months the absence of E. crassipes and its associated fauna in the study area was evident, but in January 1998, we found a partial reestablishment of E. crassipes and its associated fauna. Four months later, this community was almost back to pre-hurricane levels.

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

    Directory of Open Access Journals (Sweden)

    Verena Häussermann

    2005-12-01

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

  17. Genomic and metabolic diversity of Marine Group I Thaumarchaeota in the mesopelagic of two subtropical gyres.

    Directory of Open Access Journals (Sweden)

    Brandon K Swan

    Full Text Available Marine Group I (MGI Thaumarchaeota are one of the most abundant and cosmopolitan chemoautotrophs within the global dark ocean. To date, no representatives of this archaeal group retrieved from the dark ocean have been successfully cultured. We used single cell genomics to investigate the genomic and metabolic diversity of thaumarchaea within the mesopelagic of the subtropical North Pacific and South Atlantic Ocean. Phylogenetic and metagenomic recruitment analysis revealed that MGI single amplified genomes (SAGs are genetically and biogeographically distinct from existing thaumarchaea cultures obtained from surface waters. Confirming prior studies, we found genes encoding proteins for aerobic ammonia oxidation and the hydrolysis of urea, which may be used for energy production, as well as genes involved in 3-hydroxypropionate/4-hydroxybutyrate and oxidative tricarboxylic acid pathways. A large proportion of protein sequences identified in MGI SAGs were absent in the marine cultures Cenarchaeum symbiosum and Nitrosopumilus maritimus, thus expanding the predicted protein space for this archaeal group. Identifiable genes located on genomic islands with low metagenome recruitment capacity were enriched in cellular defense functions, likely in response to viral infections or grazing. We show that MGI Thaumarchaeota in the dark ocean may have more flexibility in potential energy sources and adaptations to biotic interactions than the existing, surface-ocean cultures.

  18. Decadal Salinity Changes in the Oceanic Subtropical Gyres and Connection to Changes in the Global Water Cycle

    Science.gov (United States)

    Melzer, Bryce Andrew

    There is evidence that the global water cycle has been undergoing an intensification over several decades as a response to increasing atmospheric temperatures, particularly in regions with skewed evaporation - precipitation (E-P) patterns such as the oceanic subtropical gyres. However, observational data (rain gauges, etc.) can be quite sparse over such areas due to the inaccessibility of open ocean regions. This study utilizes in situ data, reanalysis, and model outputs to infer interannual to decadal scale trends in surface freshwater forcing within remote, evaporation-dominated subtropical regions of the ocean as they pertain to the past and present state of the global water cycle. Emphasized in this study is the importance of utilizing a wide range of ocean parameters to strengthen and validate the inferences made from any one proxy of a given parameter. A positive trend in sea surface salinity in the subtropical gyres revealed evidence for decadal intensification in the surface forcing of these regions. Zonal drift in the location of the salinity maximum of the south Pacific, north Atlantic, and south Indian regions implies a change in the mean near-surface currents responsible for advecting high salinity waters into the region. Additionally, a comparison of satellite, in situ, and model salinity datasets was conducted to highlight the potential applications of Aquarius and SMOS satellite-derived salinity products over oceanic regions of low observational density. Spatial and temporal salinity trends in the five subtropical gyre regions were also analyzed over the past six decades, with a focus on the subsurface salinity of the upper 1000 m of the ocean. Our results indicate an overall salinity increase within the mixed layer, and a salinity decrease at depths greater than 200m in the global subtropical gyres over 61 years. Our analysis of decadal variability of depth-integrated mixed layer fluxes into and out of the gyres reveals little change in the strength

  19. Evidence for a Holocene Climatic Optimum in the southwest Pacific: A multiproxy study

    Science.gov (United States)

    Prebble, J. G.; Bostock, H. C.; Cortese, G.; Lorrey, A. M.; Hayward, B. W.; Calvo, E.; Northcote, L. C.; Scott, G. H.; Neil, H. L.

    2017-08-01

    The early Holocene sea surface temperature (SST) gradient across the subtropical front (STF) to the east of New Zealand was 2°C (measured between core sites MD97-2121 and MD97-2120): considerably less than the 6°C modern gradient between the two core sites. We document the surface ocean temperatures east and south of New Zealand during the early and middle Holocene, to test and expand upon this reconstruction. This new study samples a latitudinal transect of seven sediment cores from 37°S to 60°S in the southwest Pacific from subtropical waters north of New Zealand to polar waters in the Southern Ocean. Our compilation of SST proxies consists of 525 SST estimates from five different methods and includes 243 new data points. We confirm that an early Holocene warm peak in this region was mostly restricted to the area immediately south of the STF, which resulted in a lower temperature gradient across the STF than in modern times. However, there is no change in Holocene SST south of the polar front. Faunal assemblages suggest an early Holocene meridional expansion of fauna characteristic of the modern subtropical front in the Bounty Gyre. We suggest that such an expansion could be achieved by a reduced inflow of Subantarctic Surface Water into the Bounty Gyre. Results from a modern-analog matching platform called the Past Interpretation of Climate Tool (PICT) suggest that the early Holocene SST is most consistent with reduced westerly winds in the New Zealand sector of the Southern Ocean.

  20. Ciguatoxins and Maitotoxins in Extracts of Sixteen Gambierdiscus Isolates and One Fukuyoa Isolate from the South Pacific and Their Toxicity to Mice by Intraperitoneal and Oral Administration

    Directory of Open Access Journals (Sweden)

    Rex Munday

    2017-06-01

    Full Text Available Ciguatoxins (CTXs, and possibly maitotoxins (MTXs, are responsible for Ciguatera Fish Poisoning, an important health problem for consumers of reef fish (such as inhabitants of islands in the South Pacific Ocean. The habitational range of the Gambierdiscus species is expanding, and new species are being discovered. In order to provide information on the potential health risk of the Gambierdiscus species, and one Fukuyoa species (found in the Cook Islands, the Kermadec Islands, mainland New Zealand, and New South Wales, Australia, 17 microalgae isolates were collected from these areas. Unialgal cultures were grown and extracts of the culture isolates were analysed for CTXs and MTXs by liquid chromatography tandem mass spectrometry (LC-MS/MS, and their toxicity to mice was determined by intraperitoneal and oral administration. An isolate of G. carpenteri contained neither CTXs nor MTXs, while 15 other isolates (including G. australes, G. cheloniae, G. pacificus, G. honu, and F. paulensis contained only MTX-1 and/or MTX-3. An isolate of G. polynesiensis contained both CTXs and MTX-3. All the extracts were toxic to mice by intraperitoneal injection, but those containing only MTX-1 and/or -3 were much less toxic by oral administration. The extract of G. polynesiensis was highly toxic by both routes of administration.

  1. Low health-related quality of life in school-aged children in Tonga, a lower-middle income country in the South Pacific

    Directory of Open Access Journals (Sweden)

    Solveig Petersen

    2014-08-01

    Full Text Available Background: Ensuring a good life for all parts of the population, including children, is high on the public health agenda in most countries around the world. Information about children's perception of their health-related quality of life (HRQoL and its socio-demographic distribution is, however, limited and almost exclusively reliant on data from Western higher income countries. Objectives: To investigate HRQoL in schoolchildren in Tonga, a lower income South Pacific Island country, and to compare this to HRQoL of children in other countries, including Tongan children living in New Zealand, a high-income country in the same region. Design: A cross-sectional study from Tonga addressing all secondary schoolchildren (11–18 years old on the outer island of Vava'u and in three districts of the main island of Tongatapu (2,164 participants. A comparison group drawn from the literature comprised children in 18 higher income and one lower income country (Fiji. A specific New Zealand comparison group involved all children of Tongan descendent at six South Auckland secondary schools (830 participants. HRQoL was assessed by the self-report Pediatric Quality of Life Inventory 4.0. Results: HRQoL in Tonga was overall similar in girls and boys, but somewhat lower in children below 15 years of age. The children in Tonga experienced lower HRQoL than the children in all of the 19 comparison countries, with a large difference between children in Tonga and the higher income countries (Cohen's d 1.0 and a small difference between Tonga and the lower income country Fiji (Cohen's d 0.3. The children in Tonga also experienced lower HRQoL than Tongan children living in New Zealand (Cohen's d 0.6. Conclusion: The results reveal worrisome low HRQoL in children in Tonga and point towards a potential general pattern of low HRQoL in children living in lower income countries, or, alternatively, in the South Pacific Island countries.

  2. Perfluoroalkylated substances in the global tropical and subtropical surface oceans.

    Science.gov (United States)

    González-Gaya, Belén; Dachs, Jordi; Roscales, Jose L; Caballero, Gemma; Jiménez, Begoña

    2014-11-18

    In this study, perfluoroalkylated substances (PFASs) were analyzed in 92 surface seawater samples taken during the Malaspina 2010 expedition which covered all the tropical and subtropical Atlantic, Pacific and Indian oceans. Nine ionic PFASs including C6-C10 perfluoroalkyl carboxylic acids (PFCAs), C4 and C6-C8 perfluoroalkyl sulfonic acids (PFSAs) and two neutral precursors perfluoroalkyl sulfonamides (PFASAs), were identified and quantified. The Atlantic Ocean presented the broader range in concentrations of total PFASs (131-10900 pg/L, median 645 pg/L, n = 45) compared to the other oceanic basins, probably due to a better spatial coverage. Total concentrations in the Pacific ranged from 344 to 2500 pg/L (median = 527 pg/L, n = 27) and in the Indian Ocean from 176 to 1976 pg/L (median = 329, n = 18). Perfluorooctanesulfonic acid (PFOS) was the most abundant compound, accounting for 33% of the total PFASs globally, followed by perfluorodecanoic acid (PFDA, 22%) and perfluorohexanoic acid (PFHxA, 12%), being the rest of the individual congeners under 10% of total PFASs, even for perfluorooctane carboxylic acid (PFOA, 6%). PFASAs accounted for less than 1% of the total PFASs concentration. This study reports the ubiquitous occurrence of PFCAs, PFSAs, and PFASAs in the global ocean, being the first attempt, to our knowledge, to show a comprehensive assessment in surface water samples collected in a single oceanic expedition covering tropical and subtropical oceans. The potential factors affecting their distribution patterns were assessed including the distance to coastal regions, oceanic subtropical gyres, currents and biogeochemical processes. Field evidence of biogeochemical controls on the occurrence of PFASs was tentatively assessed considering environmental variables (solar radiation, temperature, chlorophyll a concentrations among others), and these showed significant correlations with some PFASs, but explaining small to moderate percentages of variability

  3. On North Pacific circulation and associated marine debris concentration.

    Science.gov (United States)

    Howell, Evan A; Bograd, Steven J; Morishige, Carey; Seki, Michael P; Polovina, Jeffrey J

    2012-01-01

    Marine debris in the oceanic realm is an ecological concern, and many forms of marine debris negatively affect marine life. Previous observations and modeling results suggest that marine debris occurs in greater concentrations within specific regions in the North Pacific Ocean, such as the Subtropical Convergence Zone and eastern and western "Garbage Patches". Here we review the major circulation patterns and oceanographic convergence zones in the North Pacific, and discuss logical mechanisms for regional marine debris concentration, transport, and retention. We also present examples of meso- and large-scale spatial variability in the North Pacific, and discuss their relationship to marine debris concentration. These include mesoscale features such as eddy fields in the Subtropical Frontal Zone and the Kuroshio Extension Recirculation Gyre, and interannual to decadal climate events such as El Niño and the Pacific Decadal Oscillation/North Pacific Gyre Oscillation. Published by Elsevier Ltd.

  4. Widespread detection of a brominated flame retardant, hexabromocyclododecane, in expanded polystyrene marine debris and microplastics from South Korea and the Asia-Pacific coastal region.

    Science.gov (United States)

    Jang, Mi; Shim, Won Joon; Han, Gi Myung; Rani, Manviri; Song, Young Kyoung; Hong, Sang Hee

    2017-12-01

    The role of marine plastic debris and microplastics as a carrier of hazardous chemicals in the marine environment is an emerging issue. This study investigated expanded polystyrene (EPS, commonly known as styrofoam) debris, which is a common marine debris item worldwide, and its additive chemical, hexabromocyclododecane (HBCD). To obtain a better understanding of chemical dispersion via EPS pollution in the marine environment, intensive monitoring of HBCD levels in EPS debris and microplastics was conducted in South Korea, where EPS is the predominant marine debris originate mainly from fishing and aquaculture buoys. At the same time, EPS debris were collected from 12 other countries in the Asia-Pacific region, and HBCD concentrations were measured. HBCD was detected extensively in EPS buoy debris and EPS microplastics stranded along the Korean coasts, which might be related to the detection of a quantity of HBCD in non-flame-retardant EPS bead (raw material). The wide detection of the flame retardant in sea-floating buoys, and the recycling of high-HBCD-containing EPS waste inside large buoys highlight the need for proper guidelines for the production and use of EPS raw materials, and the recycling of EPS waste. HBCD was also abundantly detected in EPS debris collected from the Asia-Pacific coastal region, indicating that HBCD contamination via EPS debris is a common environmental issue worldwide. Suspected tsunami debris from Alaskan beaches indicated that EPS debris has the potential for long-range transport in the ocean, accompanying the movement of hazardous chemicals. The results of this study indicate that EPS debris can be a source of HBCD in marine environments and marine food web. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Systematic Review and Meta-Analysis of Association of Smokeless Tobacco and of Betel Quid without Tobacco with Incidence of Oral Cancer in South Asia and the Pacific

    Science.gov (United States)

    Gupta, Bhawna; Johnson, Newell W.

    2014-01-01

    Aim This systematic review and meta-analysis aimed to critically appraised data from comparable studies leading to quantitative assessment of any independent association between use of oral smokeless tobacco in any form, of betel quid without tobacco and of areca nut with incidence of oral cancer in South Asia and the Pacific. Methods Studies (case control and/or cohort) were identified by searching Pub Med, CINAHL and Cochrane databases through June 2013 using the keywords oral cancer: chewing tobacco; smokeless tobacco; betel quid; betel quid without tobacco; areca nut; Asia, the Pacific and the reference lists of retrieved articles. A random effects model was used to compute adjusted summary ORRE for the main effect of these habits along with their corresponding 95% confidence intervals. To quantify the impact of between-study heterogeneity on adjusted main-effect summary ORRE, Higgins' H and I2 statistics along with their 95% uncertainty intervals were used. Funnel plots and Egger's test were used to evaluate publication bias. Results Meta-analysis of fifteen case–control studies (4,553 cases; 8,632 controls) and four cohort studies (15,342) which met our inclusion criteria showed that chewing tobacco is significantly and independently associated with an increased risk of squamous-cell carcinoma of the oral cavity (adjusted main-effect summary for case- control studies ORRE = 7.46; 95% CI = 5.86–9.50, Poral cancer, with OR = 2.82 (95% CI = 2.35–3.40, Poral cancer in these populations. However, studies with better separation of the types of tobacco and the ways in which it is used, and studies with sufficient power to quantify dose-response relationships are still needed. PMID:25411778

  6. Systematic review and meta-analysis of association of smokeless tobacco and of betel quid without tobacco with incidence of oral cancer in South Asia and the Pacific.

    Science.gov (United States)

    Gupta, Bhawna; Johnson, Newell W

    2014-01-01

    This systematic review and meta-analysis aimed to critically appraised data from comparable studies leading to quantitative assessment of any independent association between use of oral smokeless tobacco in any form, of betel quid without tobacco and of areca nut with incidence of oral cancer in South Asia and the Pacific. Studies (case control and/or cohort) were identified by searching Pub Med, CINAHL and Cochrane databases through June 2013 using the keywords oral cancer: chewing tobacco; smokeless tobacco; betel quid; betel quid without tobacco; areca nut; Asia, the Pacific and the reference lists of retrieved articles. A random effects model was used to compute adjusted summary OR(RE) for the main effect of these habits along with their corresponding 95% confidence intervals. To quantify the impact of between-study heterogeneity on adjusted main-effect summary OR(RE), Higgins' H and I2 statistics along with their 95% uncertainty intervals were used. Funnel plots and Egger's test were used to evaluate publication bias. Meta-analysis of fifteen case-control studies (4,553 cases; 8,632 controls) and four cohort studies (15,342) which met our inclusion criteria showed that chewing tobacco is significantly and independently associated with an increased risk of squamous-cell carcinoma of the oral cavity (adjusted main-effect summary for case- control studies OR(RE) = 7.46; 95% CI = 5.86-9.50, Ptobacco to have an independent positive association with oral cancer, with OR = 2.82 (95% CI = 2.35-3.40, Ptobacco, often used as a component of betel quid, and betel quid without tobacco, are both strong and independent risk factors for oral cancer in these populations. However, studies with better separation of the types of tobacco and the ways in which it is used, and studies with sufficient power to quantify dose-response relationships are still needed.

  7. NOAA marine environmental buoy data from moored buoys from the US East/West coasts, South Pacific, Gulf of Mexico, and the Great Lakes of US and other locations from 2001-07-01 to 2001-07-31 (NODC Accession 0000587)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Wind wave spectra and meteorological data were collected from the US East/West coasts, South Pacific, Gulf of Mexico, Great Lakes and other locations. Data were...

  8. PIGMENTS, SPECIES IDENTIFICATION - LIFE STAGE and SPECIES IDENTIFICATION - WET WEIGHT site samples data collected in the South Pacific Ocean on the LAURENCE M. GOULD cruises LMG0106 and LMG0205 as part of the Southern Ocean GLOBEC project from 2001-08-06 to 2002-09-09 (NODC Accession 0112635)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112635 includes site samples and biological data collected aboard the LAURENCE M. GOULD during cruises LMG0106 and LMG0205 in the South Pacific Ocean...

  9. Wind Wave Spectra and other data from moored buoy casts in the Gulf of Mexico, South Pacific Ocean, Coastal Waters of Western U.S., East Coast - US/Canada, and Great lakes from 01 November 2000 to 30 November 2000 (NODC Accession 0000351)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Wind wave spectra and other data were collected at fixed platforms in the Gulf of Mexico, South Pacific Ocean, Coastal Waters of Western U.S., East Coast -...

  10. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from MELVILLE in the South Pacific Ocean from 2010-01-05 to 2010-02-11 (NCEI Accession 0144244)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0144244 includes Surface underway data collected from MELVILLE in the South Pacific Ocean from 2010-01-05 to 2010-02-11. These data include AIR...

  11. Partial pressure (or fugacity) of carbon dioxide, salinity and SEA SURFACE TEMPERATURE collected from time series observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from Polaris II in the South Pacific Ocean from 2006-08-29 to 2006-10-24 (NODC Accession 0112883)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0112883 includes time series data collected from Polaris II in the South Pacific Ocean from 2006-08-29 to 2006-10-24. These data include Partial...

  12. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Barometric pressure sensor, Carbon dioxide (CO2) gas analyzer and other instruments from L'ASTROLABE in the Indian Ocean, South Pacific Ocean and others from 2002-10-16 to 2006-12-31 (NCEI Accession 0157276)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157276 includes Surface underway, chemical, meteorological and physical data collected from L'ASTROLABE in the Indian Ocean, South Pacific Ocean,...

  13. Dissolved inorganic carbon, alkalinity, temperature, salinity and SEA SURFACE TEMPERATURE collected from discrete sample and profile observations using CTD, bottle and other instruments from L'ASTROLABE in the Indian Ocean, South Pacific Ocean and others from 2002-10-16 to 2012-03-06 (NCEI Accession 0157351)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157351 includes chemical, discrete sample, physical and profile data collected from L'ASTROLABE in the Indian Ocean, South Pacific Ocean, Southern...

  14. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the AURORA AUSTRALIS in the Indian Ocean and South Pacific Ocean from 1994-12-13 to 1995-02-01 (NODC Accession 0115020)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115020 includes chemical, discrete sample, physical and profile data collected from AURORA AUSTRALIS in the Indian Ocean and South Pacific Ocean from...

  15. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from MELVILLE in the South Pacific Ocean and Tasman Sea from 2009-11-21 to 2010-02-11 (NODC Accession 0109920)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0109920 includes discrete sample and profile data collected from MELVILLE in the South Pacific Ocean and Tasman Sea from 2009-11-21 to 2010-02-11 and...

  16. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the MELVILLE in the Coral Sea and South Pacific Ocean from 1994-03-27 to 1994-06-25 (NODC Accession 0115761)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115761 includes chemical, discrete sample, physical and profile data collected from MELVILLE in the Coral Sea and South Pacific Ocean from 1994-03-27...

  17. Temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the NATHANIEL B. PALMER in the South Pacific Ocean from 1994-02-14 to 1994-04-05 (NODC Accession 0116067)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0116067 includes chemical, discrete sample, physical and profile data collected from NATHANIEL B. PALMER in the South Pacific Ocean from 1994-02-14 to...

  18. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the ROGER REVELLE in the South Pacific Ocean from 1997-12-02 to 1998-01-03 (NODC Accession 0116136)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0116136 includes chemical, discrete sample, physical and profile data collected from ROGER REVELLE in the South Pacific Ocean from 1997-12-02 to...

  19. Temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the NATHANIEL B. PALMER in the South Pacific Ocean from 2000-02-15 to 2000-03-24 (NODC Accession 0116066)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0116066 includes chemical, discrete sample, physical and profile data collected from NATHANIEL B. PALMER in the South Pacific Ocean from 2000-02-15 to...

  20. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from NATHANIEL B. PALMER in the Indian Ocean, South Pacific Ocean and others from 1995-03-17 to 1995-04-27 (NCEI Accession 0157358)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157358 includes Surface underway, chemical, meteorological and physical data collected from NATHANIEL B. PALMER in the Indian Ocean, South Pacific...

  1. Partial pressure (or fugacity) of carbon dioxide, dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the THOMAS WASHINGTON in the South Pacific Ocean from 1991-07-16 to 1991-08-25 (NODC Accession 0115171)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115171 includes chemical, discrete sample, physical and profile data collected from THOMAS WASHINGTON in the South Pacific Ocean from 1991-07-16 to...

  2. Documentation only - no data type documentation only - no observation type data collected in the South Pacific Ocean on the LAURENCE M. GOULD cruise LMG0106 as part of the Southern Ocean GLOBEC project from 2001-08-06 to 2001-11-10 (NODC Accession 0115276)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115276 includes documentation only - no observation type data collected aboard the LAURENCE M. GOULD during cruise LMG0106 in the South Pacific Ocean...

  3. INCOMING SOLAR RADIATION time series data collected in the South Pacific Ocean on the LAURENCE M. GOULD cruise LMG0106 as part of the Southern Ocean GLOBEC project from 2001-08-06 to 2001-11-10 (NODC Accession 0112375)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112375 includes meteorological and time series data collected aboard the LAURENCE M. GOULD during cruise LMG0106 in the South Pacific Ocean from...

  4. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from the FRANKLIN in the South Pacific Ocean from 2001-05-24 to 2001-07-07 (NODC Accession 0108083)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0108083 includes chemical, discrete sample, physical and profile data collected from FRANKLIN in the South Pacific Ocean from 2001-05-24 to 2001-07-07...

  5. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the AURORA AUSTRALIS in the Indian Ocean and South Pacific Ocean from 1996-08-22 to 1996-09-21 (NODC Accession 0113761)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0113761 includes chemical, discrete sample, physical and profile data collected from AURORA AUSTRALIS in the Indian Ocean and South Pacific Ocean from...

  6. Partial pressure (or fugacity) of carbon dioxide, dissolved inorganic carbon, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the KNORR in the South Pacific Ocean and Tasman Sea from 1992-05-02 to 1992-07-30 (NODC Accession 0115018)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115018 includes chemical, discrete sample, physical and profile data collected from KNORR in the South Pacific Ocean and Tasman Sea from 1992-05-02...

  7. CHLOROPHYLL A and BACTERIA - BACTERIAL DENSITY profile data collected in the South Pacific Ocean on the LAURENCE M. GOULD cruises LMG0104 and LMG0106 as part of the Southern Ocean GLOBEC project from 2001-04-29 to 2001-08-20 (NODC Accession 0112521)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112521 includes profile and biological data collected aboard the LAURENCE M. GOULD during cruises LMG0104 and LMG0106 in the South Pacific Ocean from...

  8. Temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from AURORA AUSTRALIS in the Indian Ocean, South Pacific Ocean and Southern Oceans from 2011-01-04 to 2011-02-06 (NCEI Accession 0143947)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0143947 includes discrete sample and profile data collected from AURORA AUSTRALIS in the Indian Ocean, South Pacific Ocean and Southern Oceans (>...

  9. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from unknown platforms in the South Pacific Ocean and Southern Oceans from 2010-12-28 to 2014-02-21 (NCEI Accession 0160574)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0160574 includes chemical, discrete sample, physical and profile data collected from unknown platforms in the South Pacific Ocean and Southern Oceans...

  10. Temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the NATHANIEL B. PALMER in the South Pacific Ocean from 1996-08-30 to 1996-09-24 (NODC Accession 0116063)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0116063 includes chemical, discrete sample, physical and profile data collected from NATHANIEL B. PALMER in the South Pacific Ocean from 1996-08-30 to...

  11. Partial pressure (or fugacity) of carbon dioxide, dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from NOAA Ship DISCOVERER in the South Pacific Ocean, Southern Oceans and Tasman Sea from 1996-01-05 to 1996-03-10 (NODC Accession 0115155)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0115155 includes chemical, discrete sample, physical and profile data collected from NOAA Ship DISCOVERER in the South Pacific Ocean, Southern Oceans...

  12. Dissolved inorganic carbon, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from AURORA AUSTRALIS in the Indian Ocean, South Pacific Ocean and others from 1993-04-04 to 1993-05-09 (NODC Accession 0115004)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0115004 includes chemical, discrete sample, physical and profile data collected from AURORA AUSTRALIS in the Indian Ocean, South Pacific Ocean,...

  13. Partial pressure (or fugacity) of carbon dioxide, dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from NATHANIEL B. PALMER in the South Pacific Ocean, Southern Oceans and Tasman Sea from 2014-03-20 to 2014-05-05 (NCEI Accession 0157621)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157621 includes chemical, discrete sample, meteorological, optical, physical and profile data collected from NATHANIEL B. PALMER in the South Pacific...

  14. Partial pressure (or fugacity) of carbon dioxide, temperature, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, PAR Sensor and other instruments from NATHANIEL B. PALMER in the South Pacific Ocean and Southern Oceans from 1997-11-25 to 1997-12-08 (NCEI Accession 0157301)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157301 includes Surface underway, biological, chemical, optical and physical data collected from NATHANIEL B. PALMER in the South Pacific Ocean and...

  15. Cloud amount/frequency, NITRATE and other data from XIANG YANG HONG 09, 3-141 and other platforms in the TOGA Area - Pacific and South China Sea from 1958-09-26 to 1990-11-28 (NODC Accession 9100167)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Ocean Serial data in this accession was collected in South China Sea (Nan Hai), TOGA Area - Pacific (30 N to 30 S) as part of Tropical Ocean Global Atmosphere...

  16. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the NATHANIEL B. PALMER in the South Pacific Ocean from 1997-04-04 to 1997-05-12 (NODC Accession 0116065)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0116065 includes chemical, discrete sample, physical and profile data collected from NATHANIEL B. PALMER in the South Pacific Ocean from 1997-04-04 to...

  17. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from MIRAI in the Indian Ocean, South Pacific Ocean and Southern Oceans from 2012-11-28 to 2013-01-04 (NCEI Accession 0143950)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0143950 includes discrete sample and profile data collected from MIRAI in the Indian Ocean, South Pacific Ocean and Southern Oceans (> 60 degrees...

  18. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Barometric pressure sensor, Carbon dioxide (CO2) gas analyzer and other instruments from L'ASTROLABE in the Indian Ocean, South Pacific Ocean and others from 1996-10-21 to 1996-11-23 (NCEI Accession 0157233)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157233 includes Surface underway, chemical, meteorological, optical and physical data collected from L'ASTROLABE in the Indian Ocean, South Pacific...

  19. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Barometric pressure sensor, Carbon dioxide (CO2) gas analyzer and other instruments from L'ASTROLABE in the Indian Ocean, South Pacific Ocean and others from 1997-02-02 to 1997-02-17 (NCEI Accession 0157416)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157416 includes Surface underway, chemical, meteorological, optical and physical data collected from L'ASTROLABE in the Indian Ocean, South Pacific...

  20. Partial pressure (or fugacity) of carbon dioxide, salinity and SEA SURFACE TEMPERATURE collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from Munida in the South Pacific Ocean from 2004-01-26 to 2006-07-30 (NODC Accession 0100218)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0100218 includes Surface underway data collected from Munida in the South Pacific Ocean from 2004-01-26 to 2006-07-30. These data include Partial...

  1. Temperature, salinity and other variables collected from discrete sample and profile observations using CTD, PAR Sensor and other instruments from AURORA AUSTRALIS in the Indian Ocean, South Pacific Ocean and Southern Oceans from 2007-12-16 to 2008-01-27 (NCEI Accession 0143932)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0143932 includes discrete sample and profile data collected from AURORA AUSTRALIS in the Indian Ocean, South Pacific Ocean and Southern Oceans (>...

  2. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, Coulometer for DIC measurement and other instruments from the HAKUREI MARU in the South Pacific Ocean from 1996-04-12 to 1996-06-10 (NODC Accession 0112341)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112341 includes biological, chemical, discrete sample, physical and profile data collected from HAKUREI MARU in the South Pacific Ocean from...

  3. Temperature profiles from mechanical bathythermograph (MBT) casts from the USS CONFLICT in the North and South Pacific Oceans in support of the Fleet Observations of Oceanographic Data (FLOOD) project from 1966-07-12 to 1966-07-19 (NODC Accession 6600091)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — MBT data were collected from the USS CONFLICT in support of the Fleet Observations of Oceanographic Data (FLOOD) project. Data were collected North and South Pacific...

  4. Partial pressure (or fugacity) of carbon dioxide, dissolved inorganic carbon, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the AKADEMIK IOFFE in the South Pacific Ocean from 1992-02-14 to 1992-04-06 (NODC Accession 0115013)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115013 includes chemical, discrete sample, physical and profile data collected from AKADEMIK IOFFE in the South Pacific Ocean from 1992-02-14 to...

  5. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from time series observations using Bubble type equilibrator for autonomous carbon dioxide (CO2) measurement, Carbon dioxide (CO2) gas analyzer and other instruments from MOORING STRATUS_85W_20S, in the South Pacific Ocean from 2006-10-16 to 2015-04-03 (NODC Accession 0100075)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0100075 includes chemical, meteorological, physical and time series data collected from MOORING STRATUS_85W_20S in the South Pacific Ocean from...

  6. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from surface underway observations using Barometric pressure sensor, Carbon dioxide (CO2) gas analyzer and other instruments from Investigator in the Indian Ocean, South Pacific Ocean and Tasman Sea from 2015-03-21 to 2015-03-29 (NCEI Accession 0163179)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0163179 includes chemical, meteorological, physical and surface underway data collected from Investigator in the Indian Ocean, South Pacific Ocean and...

  7. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Barometric pressure sensor, Carbon dioxide (CO2) gas analyzer and other instruments from AURORA AUSTRALIS in the Indian Ocean, South Pacific Ocean and others from 2016-01-11 to 2016-02-21 (NCEI Accession 0157255)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157255 includes Surface underway, chemical, meteorological and physical data collected from AURORA AUSTRALIS in the Indian Ocean, South Pacific...

  8. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from AURORA AUSTRALIS in the Indian Ocean, South Pacific Ocean and others from 2012-01-05 to 2013-01-08 (NCEI Accession 0157307)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0157307 includes Surface underway, chemical, meteorological and physical data collected from AURORA AUSTRALIS in the Indian Ocean, South Pacific...

  9. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from underway - surface observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from the AURORA AUSTRALIS in the Indian Ocean, South Pacific Ocean and Tasman Sea from 2011-01-04 to 2011-11-28 (NODC Accession 0115179)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115179 includes chemical, meteorological, physical and underway - surface data collected from AURORA AUSTRALIS in the Indian Ocean, South Pacific...

  10. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Barometric pressure sensor, Carbon dioxide (CO2) gas analyzer and other instruments from AURORA AUSTRALIS in the Indian Ocean, South Pacific Ocean and others from 2014-01-29 to 2015-01-24 (NCEI Accession 0160488)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0160488 includes Surface underway, chemical, meteorological and physical data collected from AURORA AUSTRALIS in the Indian Ocean, South Pacific...

  11. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Barometric pressure sensor, Carbon dioxide (CO2) gas analyzer and other instruments from AURORA AUSTRALIS in the Indian Ocean, South Pacific Ocean and others from 2015-01-28 to 2016-01-06 (NCEI Accession 0160550)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0160550 includes Surface underway, chemical, meteorological and physical data collected from AURORA AUSTRALIS in the Indian Ocean, South Pacific...

  12. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Barometric pressure sensor, Carbon dioxide (CO2) gas analyzer and other instruments from AURORA AUSTRALIS in the Indian Ocean, South Pacific Ocean and others from 2013-01-13 to 2013-12-07 (NODC Accession 0117696)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0117696 includes Surface underway, chemical, meteorological and physical data collected from AURORA AUSTRALIS in the Indian Ocean, South Pacific...

  13. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the THOMAS G. THOMPSON in the South Pacific Ocean from 1994-01-25 to 1994-02-19 (NODC Accession 0115762)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115762 includes chemical, discrete sample, physical and profile data collected from THOMAS G. THOMPSON in the South Pacific Ocean from 1994-01-25 to...

  14. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from MIRAI in the South Pacific Ocean and Tasman Sea from 2003-08-03 to 2003-10-16 (NODC Accession 0108122)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0108122 includes chemical, discrete sample, physical and profile data collected from MIRAI in the South Pacific Ocean and Tasman Sea from 2003-08-03...

  15. Partial pressure (or fugacity) of carbon dioxide, dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from the KNORR in the South Pacific Ocean from 2005-08-21 to 2005-10-06 (NODC Accession 0108071)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0108071 includes chemical, discrete sample, physical and profile data collected from KNORR in the South Pacific Ocean from 2005-08-21 to 2005-10-06...

  16. Dissolved inorganic carbon, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the KNORR in the South Pacific Ocean from 1992-09-01 to 1992-09-15 (NODC Accession 0115700)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115700 includes chemical, discrete sample, physical and profile data collected from KNORR in the South Pacific Ocean from 1992-09-01 to 1992-09-15...

  17. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the ROGER REVELLE in the South Pacific Ocean from 1997-10-20 to 1997-11-24 (NODC Accession 0116068)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0116068 includes chemical, discrete sample, physical and profile data collected from ROGER REVELLE in the South Pacific Ocean from 1997-10-20 to...

  18. Oceanographic profile plankton, temperature, salinity collected using bottle from various unknown small boats in the South Pacific Ocean from 1981 to 1982 (NODC Accession 0002138)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature, salinity and other measurements found in dataset OSD taken from unknown platform(s)in the Coastal S Pacific, Equatorial Pacific and other locations from...

  19. Box-modeling of the impacts of atmospheric nitrogen deposition and benthic remineralization on the nitrogen cycle of the eastern tropical South Pacific

    Science.gov (United States)

    Su, B.; Pahlow, M.; Oschlies, A.

    2015-09-01

    Both atmospheric deposition and benthic remineralization influence the marine nitrogen cycle, and hence ultimately also marine primary production. The biological and biogeochemical relations of the eastern tropical South Pacific (ETSP) to nitrogen deposition, benthic denitrification and phosphate regeneration are analysed in a prognostic box model of the oxygen, nitrogen and phosphorus cycles in the ETSP. In the model, atmospheric nitrogen deposition based on estimates for the years 2000-2009 is offset by half by reduced N2 fixation, with the other half transported out of the model domain. Both model- and data-based benthic denitrification are found to trigger nitrogen fixation, partly compensating for the NO3- loss. Since phosphate is the ultimate limiting nutrient in the model, enhanced sedimentary phosphate regeneration under suboxic conditions stimulates primary production and subsequent export production and NO3- loss in the oxygen minimum zone (OMZ). A sensitivity analysis of the local response to both atmospheric deposition and benthic remineralization indicates dominant stabilizing feedbacks in the ETSP, which tend to keep a balanced nitrogen inventory, i.e., nitrogen input by atmospheric deposition is counteracted by decreasing nitrogen fixation; NO3- loss via benthic denitrification is partly compensated by increased nitrogen fixation; enhanced nitrogen fixation stimulated by phosphate regeneration is partly removed by the stronger water-column denitrification. Even though the water column in our model domain acts as a NO3- source, the ETSP including benthic denitrification might become a NO3- sink.

  20. Abundance patterns of early stages of the Pacific sardine (Sardinops sagax during a cooling period in a coastal lagoon south of the California Current

    Directory of Open Access Journals (Sweden)

    René Funes-Rodríguez

    2011-11-01

    Full Text Available Abundance patterns of eggs and larvae of the Pacific sardine, Sardinops sagax (Jenyns, 1842, in Bahía Magdalena, Baja California Sur, were analysed during a cooling period south of the California Current from 2005 to 2009. The thermohaline characteristics and zooplankton abundance were good descriptors of the potential spawning habitat. Individual quotient analyses showed a predominance of eggs and larvae within a SST range of 16 to 18°C, at low salinities (33.9-34.1 and at low density gradient variability (0.009-0.029, associated with deeper waters (25-40 m near the main entrance, where the transparency was intermediate (6-8 m and zooplankton abundance was relatively high ( > 316 ml/1000 m3. Increments within different class intervals meant that neither dissolved inorganic nitrogen (DIN, phosphates nor chlorophyll a predominated. The large interannual fluctuations in sardine spawning activity and preferential temperatures observed in historical and recent data suggest that two sardine stocks spawn in Bahia Magdalena: one stock spawned in the period 1981-1989 and one stock spawned in the period 1997-2009. The influence of cooling and warming periods as additional components of the regional environmental framework is analysed and discussed.