WorldWideScience

Sample records for central north pacific

  1. Decadal oscillation of autumn precipitation in Central Vietnam modulated by the East Pacific-North Pacific (EP-NP) teleconnection

    Science.gov (United States)

    Li, R.; Wang, S.-Y.; Gillies, R. R.; Buckley, B. M.; Truong, L. H.; Cho, C.

    2015-02-01

    Autumn precipitation over Central Vietnam is associated with an increase in the occurrence of tropical cyclones that lead to frequent flooding and pose a significant threat to lives and property. The present analyses reveal a pronounced decadal oscillation of autumn precipitation in Central Vietnam within the 8-11 year frequency band that is modulated by the East Pacific-North Pacific (EP-NP) teleconnection. The negative phase of the EP-NP pattern is associated with a positive sea surface temperature (SST) anomaly in the South China Sea (SCS) that induces low-level convergence, enhances convection, and increases precipitation over Central Vietnam and adjacent islands including Hainan (China) and the Philippines. This circulation feature around the SCS is embedded in a large-scale circulation associated with SST anomalies across the Pacific Ocean—i.e., cooling in the Eastern and Central tropical Pacific sandwiched by warming in the North and South Pacific as well as the Western Pacific Ocean. The positive phase of the EP-NP features opposite SST and circulation anomalies, with the result being reduced rainfall in Central Vietnam. This out-of-phase relationship and shared decadal spectral coherence between the EP-NP index and autumn precipitation in Central Vietnam might be useful for future climate predictions and flood management.

  2. Changing central Pacific El Niños reduce stability of North American salmon survival rates.

    Science.gov (United States)

    Kilduff, D Patrick; Di Lorenzo, Emanuele; Botsford, Louis W; Teo, Steven L H

    2015-09-01

    Pacific salmon are a dominant component of the northeast Pacific ecosystem. Their status is of concern because salmon abundance is highly variable--including protected stocks, a recently closed fishery, and actively managed fisheries that provide substantial ecosystem services. Variable ocean conditions, such as the Pacific Decadal Oscillation (PDO), have influenced these fisheries, while diminished diversity of freshwater habitats have increased variability via the portfolio effect. We address the question of how recent changes in ocean conditions will affect populations of two salmon species. Since the 1980s, El Niño Southern Oscillation (ENSO) events have been more frequently associated with central tropical Pacific warming (CPW) rather than the canonical eastern Pacific warming ENSO (EPW). CPW is linked to the North Pacific Gyre Oscillation (NPGO), whereas EPW is linked to the PDO, different indicators of northeast Pacific Ocean ecosystem productivity. Here we show that both coho and Chinook salmon survival rates along western North America indicate that the NPGO, rather than the PDO, explains salmon survival since the 1980s. The observed increase in NPGO variance in recent decades was accompanied by an increase in coherence of local survival rates of these two species, increasing salmon variability via the portfolio effect. Such increases in coherence among salmon stocks are usually attributed to controllable freshwater influences such as hatcheries and habitat degradation, but the unknown mechanism underlying the ocean climate effect identified here is not directly subject to management actions. PMID:26240365

  3. Latitudinal Variation of Chemical Composition in Marine Aerosol Over the Central North Pacific in the Summer

    Science.gov (United States)

    Uematsu, M.; Narita, Y.; Mano, Y.; Iguchi, H.; Yoshida, K.; Iwamoto, Y.; Miura, K.

    2006-12-01

    Aeolian dust and gaseous and particulate pollutants from the Asian continent are transported eastward over the North Pacific. These natural and anthropogenic materials in the atmosphere can influence regional and global climate by altering the Earth's radiative balance. From the view of biogeochemical cycles, the atmospheric deposition of aerosols containing iron and other essential trace elements may contribute in sustaining primary productivity of phytoplankton, food web structure and chemical properties of marine atmosphere in the central North Pacific region. During the South-North cross-section cruise from 8 August to 21 September 2005, we conducted atmospheric sampling of aerosol and gaseous components on board R/V Hakuho Maru. Results from 10S to 53N along 160E revealed high nitrate concentration in the high latitude zone corresponded with back-air trajectories to subarctic North Pacific from the Asian continent during the summer. The atmospheric supply of nitrogen compounds may affect the primary production of stratified surface layer in the region. Non-sea-salt sulfate concentration was also high over the subarctic region, and downwind of the Hawaii islands. Volcanic and anthropogenic sulfur are suspected to be the sources of nss-sulfate. However, as an indicator of marine biogenic sulfate, methane sulfonic acid (MSA) is also correlated well with the concentration peaks of nss-sulfate both the vicinity of Hawaii islands and subarctic region. We will attempt to separate nss-sulfate into two fractions, marine biogenic and anthropogenic by using the relation between trace metals and sulfate over the source regions.

  4. Decadal oscillation of autumn precipitation in Central Vietnam modulated by the East Pacific–North Pacific (EP–NP) teleconnection

    International Nuclear Information System (INIS)

    Autumn precipitation over Central Vietnam is associated with an increase in the occurrence of tropical cyclones that lead to frequent flooding and pose a significant threat to lives and property. The present analyses reveal a pronounced decadal oscillation of autumn precipitation in Central Vietnam within the 8–11 year frequency band that is modulated by the East Pacific–North Pacific (EP–NP) teleconnection. The negative phase of the EP–NP pattern is associated with a positive sea surface temperature (SST) anomaly in the South China Sea (SCS) that induces low-level convergence, enhances convection, and increases precipitation over Central Vietnam and adjacent islands including Hainan (China) and the Philippines. This circulation feature around the SCS is embedded in a large-scale circulation associated with SST anomalies across the Pacific Ocean—i.e., cooling in the Eastern and Central tropical Pacific sandwiched by warming in the North and South Pacific as well as the Western Pacific Ocean. The positive phase of the EP–NP features opposite SST and circulation anomalies, with the result being reduced rainfall in Central Vietnam. This out-of-phase relationship and shared decadal spectral coherence between the EP–NP index and autumn precipitation in Central Vietnam might be useful for future climate predictions and flood management. (letter)

  5. Seasonal abundance of the microplankton population in the North Pacific central gyre

    Science.gov (United States)

    Beers, John R.; Reid, Freda M. H.; Stewart, Gene L.

    1982-02-01

    Population structure as numerical and biomas abundance was determined for the microplankton (˜ to 200 μm organisms) sampled throughout and just below the euphotic zone at five times of year other than fall in the North Pacific central gyre around 28°N, 155°W. Average total microplankton carbon of all strata varied by twofold or less over the cruises, conforming to the hypothesis of low heterogeneity of biomass in central oceanic gyral populations. For example, mean euphotic zone abundance ranged from 5.9 μg Cl -1 (late winter) to 10.5 μg Cl -1 (spring), averaging 7.9 μg Cl -1. Its variability and that of stations within cruises were similar. Microplankton did not show a maximum correlated with the chlorophyll α maximum seen near the base of the euphotic zone when there was thermal stratification within the euphotic zone. Nanoplankters consistently dominated the population. 'Monads and flagellates' and non-thecate dinoflagellates were the most abundant groups. Diatoms in the upper waters where temperature range was the widest were the most temporally variable. Statistically significant differences in the biomass of taxonomic groups between cruises were found in relatively few of the possible instances tested.

  6. 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.

  7. Detection of nonylphenol and persistent organic pollutants in fish from the North Pacific Central Gyre.

    Science.gov (United States)

    Gassel, Margy; Harwani, Suhash; Park, June-Soo; Jahn, Andrew

    2013-08-15

    Despite scientific and public concern, research on food web contamination from chemicals in plastic is limited, and distinguishing plastic sources from prey remains a challenge. We analyzed juvenile yellowtail (Seriola lalandi) from the North Pacific Central Gyre for plastic ingestion and tissue concentrations of persistent organic pollutants and nonionic surfactants to investigate potential contamination from plastic exposure. Ingestion of synthetic debris occurred in ~10% of the sample population. PCBs and DDTs were 352±240 (mean±SD) and 1425±1118 ng/g lw, respectively. PBDEs were 9.08±10.6 ng/g lw, with BDEs-47, 99, and 209 representing 90% of PBDEs. Nonylphenol (NP) was detected in one-third of the yellowtail with a mean of 52.8±88.5 ng/g ww overall and 167±72.3 ng/g ww excluding non-detects. Because environmental NP is strongly associated with wastewater treatment effluents, long-range transport is unlikely, and NP was previously measured in gyre plastic, we concluded that plastic-mediated exposure best explained our findings of NP in yellowtail. PMID:23746941

  8. Impacts of decaying eastern and central Pacific El Niños on tropical cyclone activities over the western North Pacific in summer

    Science.gov (United States)

    Yang, Yuxing; Xie, Ruihuang; Wang, Faming; Huang, Fei

    2016-07-01

    We investigate the influences of the decaying eastern Pacific El Niño (EP-El Niño) and central Pacific El Niño (CP-El Niño) on tropical cyclone (TC) activities in the western North Pacific (WNP) during July, August, and September (JAS). During this period, TC geneses and tracks are reduced in the central and eastern WNP. However, TC tracks reaching the Philippines increase, and more TC geneses appear west of 145°E during EP-El Niño. During CP-El Niño, tracks reaching the South China Sea (SCS) and southeast coast of China increase, and positive anomalies of TC genesis are found in the southern part of the central WNP and southern SCS. It is possible that the different variations of the anomalous anticyclone over east of the Philippines in the WNP induced by El Niños are instrumental to the different TC variations in the two types of decaying El Niños during JAS. Compared with EP-El Niño, strengthening and northward expansion of the anomalous anticyclone during CP-El Niño cause a westward shift of the western Pacific subtropical high in summer, which is responsible for more westward TC tracks over the SCS and southeast coast of China. This northward expansion can cause the center of suppressed TC geneses in the central WNP to migrate further north during CP-El Niño. A decreased magnitude of vertical shear dominates the southern part of the central WNP and southern SCS, which enhances TC formation in these regions during CP-El Niño.

  9. Identifying Pelagic Habitat Hotspots of Neon Flying Squid in the Temperate Waters of the Central North Pacific.

    Directory of Open Access Journals (Sweden)

    Irene D Alabia

    Full Text Available We identified the pelagic habitat hotspots of the neon flying squid (Ommastrephes bartramii in the central North Pacific from May to July and characterized the spatial patterns of squid aggregations in relation to oceanographic features such as mesoscale oceanic eddies and the Transition Zone Chlorophyll-a Front (TZCF. The data used for the habitat model construction and analyses were squid fishery information, remotely-sensed and numerical model-derived environmental data from May to July 1999-2010. Squid habitat hotspots were deduced from the monthly Maximum Entropy (MaxEnt models and were identified as regions of persistent high suitable habitat across the 12-year period. The distribution of predicted squid habitat hotspots in central North Pacific revealed interesting spatial and temporal patterns likely linked with the presence and dynamics of oceanographic features in squid's putative foraging grounds from late spring to summer. From May to June, the inferred patches of squid habitat hotspots developed within the Kuroshio-Oyashio transition zone (KOTZ; 37-40°N and further expanded north towards the subarctic frontal zone (SAFZ; 40-44°N in July. The squid habitat hotspots within the KOTZ and areas west of the dateline (160°W-180° were likely influenced and associated with the highly dynamic and transient oceanic eddies and could possibly account for lower squid suitable habitat persistence obtained from these regions. However, predicted squid habitat hotspots located in regions east of the dateline (180°-160°W from June to July, showed predominantly higher squid habitat persistence presumably due to their proximity to the mean position of the seasonally-shifting TZCF and consequent utilization of the highly productive waters of the SAFZ.

  10. AFSC/NMML: Shore-based counts of the Eastern North Pacific gray whale stock from central California, 1967 - 2007

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Marine Fisheries Service (NMFS) has conducted shore-based counts of the Eastern North Pacific stock of gray whales (Eschrichtius robustus) 26 years...

  11. Localized double-array stacking analysis of PcP: D″ and ULVZ structure beneath the Cocos plate, Mexico, central Pacific, and north Pacific

    Science.gov (United States)

    Hutko, Alexander R.; Lay, Thorne; Revenaugh, Justin

    2009-01-01

    A large, high quality P-wave data set comprising short-period and broadband signals sampling four separate regions in the lowermost mantle beneath the Cocos plate, Mexico, the central Pacific, and the north Pacific is analyzed using regional one-dimensional double-array stacking and modelling with reflectivity synthetics. A data-screening criterion retains only events with stable PcP energy in the final data stacks used for modelling and interpretation. This significantly improves the signal stacks relative to including unscreened observations, allows confident alignment on the PcP arrival and allows tight bounds to be placed on P-wave velocity structure above the core–mantle boundary (CMB). The PcP reflections under the Cocos plate are well modelled without any ultra-low velocity zone from 5 to 20°N. At latitudes from 15 to 20°N, we find evidence for two P-wave velocity discontinuities in the D″ region. The first is ∼182 km above the CMB with a δln Vp of +1.5%, near the same depth as a weaker discontinuity (<+0.5%) observed from 5 to 15°N in prior work. The other reflector is ∼454 km above the CMB, with a δln Vp of +0.4%; this appears to be a shallower continuation of the joint P- and S-wave discontinuity previously detected south of 15° N, which is presumed to be the perovskite to post-perovskite phase transition. The data stacks for paths bottoming below Mexico have PcP images that are well matched with the simple IASP91 structure, contradicting previous inferences of ULVZ presence in this region. These particular data are not very sensitive to any D″ discontinuities, and simply bound them to be <∼2%, if present. Data sampling the lowermost mantle beneath the central Pacific confirm the presence of a ∼15-km thick ultra-low velocity zone (ULVZ) just above the CMB, with δln Vp and δln Vs of around −3 to −4% and −4 to −8%, respectively. The ULVZ models predict previous S-wave data stacks well. The data for this region

  12. Hawaiian imprint on dissolved Nd and Ra isotopes and rare earth elements in the central North Pacific: Local survey and seasonal variability

    Science.gov (United States)

    Fröllje, Henning; Pahnke, Katharina; Schnetger, Bernhard; Brumsack, Hans-Jürgen; Dulai, Henrietta; Fitzsimmons, Jessica N.

    2016-09-01

    Dissolved neodymium isotopes (143Nd/144Nd, expressed as εNd) and rare earth elements (REEs) have the potential to trace the provenance of lithogenic material as well as water masses. The central North Pacific is poorly investigated with respect to its Nd isotope signature and REE cycling, and little is known about the contributions of volcanic islands, such as Hawaii, relative to dust input from Asian deserts to the surface water REE budgets. Here we present dissolved Nd isotope and REE data along with long-lived radium isotope activities from Hawaii Ocean Time-Series Station ALOHA and coastal waters from Oahu, sampled for a GEOTRACES process study in February 2011. The data are supplemented with seasonal samples from ALOHA. Our results show a clear influence of the Hawaiian Islands on the coastal ocean and surface waters at ALOHA during February, expressed by higher surface water Ra activities, radiogenic surface εNd (εNd = +1.4 to -1.0), and elevated Eu anomalies (Eu/Eu∗ ⩾ 1.3). Seasonal cycles of Asian dust deposition most likely contribute to the seasonal εNd variability of surface waters at ALOHA, as suggested by more negative εNd and the lack of Eu anomalies in summer. Neodymium isotopes in the intermediate and deep water column at ALOHA trace typical North Pacific water masses, such as North Pacific Intermediate Water and North Pacific Deep Water. We suggest that a radiogenic εNd excursion in 1000-2000 m water depth, observed in various North Pacific profiles, is controlled by advection of a modified Upper Circumpolar Deep Water or North Equatorial Pacific Intermediate Water. We further present an updated average εNd signature of -3.5 ± 0.5 for North Pacific Deep Water and show that REE patterns of deep waters at ALOHA are dominantly controlled by vertical processes.

  13. Direct observation of 134Cs and 137Cs in surface seawater in the western and central North Pacific after the Fukushima Dai-ichi nuclear power plant accident

    Directory of Open Access Journals (Sweden)

    H. Kaeriyama

    2013-06-01

    Full Text Available The horizontal distribution of radioactive cesium (Cs derived from the Fukushima Dai-ichi nuclear power plant (FNPP in the North Pacific is still unclear due to the limitation of direct measurement of the seawater in the open ocean. We present the result of direct observation of radioactive Cs in surface seawater collected from a broad area in the western and central North Pacific in July 2011, October 2011 and July 2012. We also conducted a simple particle tracking experiment to estimate the qualitative spatial distribution of radioactive Cs in the North Pacific. 134Cs was detected at 94 stations out of 123 stations, and 137Cs was detected at all stations. High 134Cs and 137Cs concentrations more than 10 m Bq kg−1 were observed in the area of the northern part of Kuroshio Extension at 144° E and 155° E in July 2011, in the area 147–175° E around 40° N in October 2011, and the northern part of Kuroshio Extension at 155° E and 175°30´ E in July 2012. Combining the result of direct observations and particle tracking experiment, the radioactive Cs derived from the FNPP had been dispersed eastward to the central North Pacific during 2011. It was considered from the horizontal distribution that radioactive Cs was dispersed not only eastward but also north- and southward in the central North Pacific. Pronounced dilution process of radioactive Cs from the FNPP during study period is suggested from temporal change in the activity ratio of 134Cs / 137Cs, which was decay-corrected on 6 April 2011, and relationships between radioactive Cs and temperature.

  14. The North Pacific Gyre Mode

    Science.gov (United States)

    Schneider, N.; di Lorenzo, E.

    2007-12-01

    Discussion of North Pacific Decadal decadal variability has focused primarily on the Pacific Decadal Oscillation, the leading mode of sea surface temperature anomalies north of the tropics. The PDO appears to result from a superposition of SST pattern forced by the North Pacific atmosphere due to its intrinsic dynamics and teleconnected from the tropics, with a regional impact of the ocean circulation in the frontal regions associated with the Kuroshio/Oyashio and their extensions into the interior. Recent modeling, however, suggest that previously unexplained decadal changes of salinity, nutrient upwelling and chlorophyl in the California Current are not dominated by the PDO. Rather, these are associated with a mode of variability associated with wind driven changes of the North Pacific Gyre. Consideration of this mode variability may thus be important to understand present and future variations of the North Pacific ecosystem, and in the interpretation of climate proxies.

  15. Uranium and thorium enrichment in rocks from the base of DSDP Hole 465A, Hess Rise, central North Pacific

    Science.gov (United States)

    Hein, J.R.; Koski, R.A.; Morgenson, L.A.

    1982-01-01

    Uranium and thorium are concentrated in Cretaceous limestone, chert, ash, basalt, and other rock types at Deep Sea Drilling Project Site 465 located on the southern Hess Rise in the central North Pacific. U concentrations, up to 194 ppm on a carbonate-free basis, are among the highest recorded for any deep-sea deposits. U was initially derived from seawater and concentrated by absorption on terrigenous (humic) organic matter in limestone in a shallow marine environment. U and Th were probably concentrated further by low-temperature hydrothermal fluids emanating from the basaltic basement. Mainly montmorillonite, an alteration product of basalt and ash, and organic matter in sedimentary rocks acted as hosts for U and Th. The unique combination of sediments rich in humic organic matter, abundant smectite in altered ash and basalt, and warm hydrothermal solutions provided the necessary conditions for migration and concentration of U and Th. To better understand the conditions limiting the migrating and concentration of U and Th, other rocks deposited during the ocean-wide Cretaceous anoxic events should be analyzed for these elements. ?? 1982.

  16. Temperature, salinity, nutrients, oxygen and other data profiles from CTD and bottle casts from NOAA/NMFS cruises of the R/V Townsend Cromwell in the central north Pacific, 1997-2002 (NODC Accession 0100295)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains measurements from CTD hydrocast stations from seven cruises of the R/V Townsend Cromwell in the central north Pacific from 1997 to 2002...

  17. The interdecadal trend and shift of dry/wet over the central part of North China and their relationship to the Pacific Decadal Oscillation (PDO)

    Institute of Scientific and Technical Information of China (English)

    MA ZhuGuo

    2007-01-01

    Based on monthly precipitation and monthly mean surface air temperature (SAT), the dry/wet trends and shift of the central part of North China and their relationship to the Pacific Decadal Oscillation (PDO) from 1951 to 2005 have been analyzed through calculating surface wetness index (SWI). The results indicate that there was a prominent drying trend and an abrupt change in the analysis period. A persistent warming period with less precipitation from the mid and late 1970s to present was found, and a shift process exists from the wet to the dry in the central part of North China during 1951-2005. The transition is located in the mid to late 1970s, which should be related to the shift variation of large-scale climate background. The correlation analysis has brought about a finding of significant correlativity between PDO index (PDOI) and SAT, precipitation and SWI in this region. The correlation exhibits that the positive phase of PDOI (warm PDO phase) matches warming, less precipitation and the drought period, and the negative PDOI phase corresponds to low SAT, more precipitation and the wet period. The duration of various phases is more than 25 years. The decadal variation of sea surface temperature (SST) in the North Pacific Ocean is one of the possible causes in forming the decadal dry/wet trend and shift of the central part of North China.

  18. North Pacific Pelagic Seabird Database (NPPSD)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The North Pacific Pelagic Seabird Database (NPPSD) was created in 2005 to consolidate data on the oceanic distribution of marine bird species in the North Pacific....

  19. Cesium-134 and 137 activities in the central North Pacific Ocean after the Fukushima Dai-ichi Nuclear Power Plant accident

    Directory of Open Access Journals (Sweden)

    J. Kameník

    2013-09-01

    Full Text Available Surface seawater 134Cs and 137Cs samples were collected in the central and western North Pacific Ocean during the 2 yr after the Fukushima Dai-ichi Nuclear Power Plant accident to monitor dispersion patterns of these radioisotopes towards the Hawaiian Islands. In the absence of other recent sources and due to its short half-life, only those parts of the Pacific Ocean would have detectable 134Cs values that were impacted by Fukushima releases. Between March and May 2011, 134Cs was not detected around the Hawaiian Islands and Guam. Here, most 137Cs activities (1.2–1.5 Bq m–3 were in the range of expected preexisting levels. Some samples north of the Hawaiian Islands (1.6–1.8 Bq m–3 were elevated above the 23-month baseline established in surface seawater in Hawaii indicating that those might carry atmospheric fallout. The 23-month time-series analysis of surface seawater from Hawaii did not reveal any seasonal variability or trends, with an average activity of 1.46 ± 0.06 Bq m–3 (Station Aloha, 18 values. In contrast, samples collected between Japan and Hawaii contained 134Cs activities in the range of 1–4 Bq m–3, and 137Cs levels were about 2–3 times above the preexisting activities. We found that the southern boundary of the Kuroshio and Kuroshio extension currents represented a boundary for radiation dispersion with higher activities detected within and north of the major currents. The radiation plume has not been detected over the past 2 yr at the main Hawaiian Islands due to the transport patterns across the Kuroshio and Kuroshio extension currents.

  20. Central Equatorial Pacific Experiment (CEPEX)

    Energy Technology Data Exchange (ETDEWEB)

    1993-01-01

    The Earth's climate has varied significantly in the past, yet climate records reveal that in the tropics, sea surface temperatures seem to have been remarkably stable, varying by less than a few degrees Celsius over geologic time. Today, the large warm pool of the western Pacific shows similar characteristics. Its surface temperature always exceeds 27[degree]C, but never 31[degree]C. Heightened interest in this observation has been stimulated by questions of global climate change and the exploration of stabilizing climate feedback processes. Efforts to understand the observed weak sensitivity of tropical sea surface temperatures to climate forcing has led to a number of competing ideas about the nature of this apparent thermostat. Although there remains disagreement on the processes that regulate tropical sea surface temperature, most agree that further progress in resolving these differences requires comprehensive field observations of three-dimensional water vapor concentrations, solar and infrared radiative fluxes, surface fluxes of heat and water vapor, and cloud microphysical properties. This document describes the Central Equatorial Pacific Experiment (CEPEX) plan to collect such observations over the central equatorial Pacific Ocean during March of 1993.

  1. Tropical Pacific impacts on cooling North American winters

    Science.gov (United States)

    Sigmond, Michael; Fyfe, John C.

    2016-10-01

    The North American continent generally experienced a cooling trend in winter over the early 2000s. This cooling trend represented a significant deviation from expected anthropogenic warming and so requires explanation. Previous studies indicate that climate variations in the tropical Pacific contributed to many mid-latitude climate variations over the early twenty-first century. Here we show using large ensembles of fully coupled, partially coupled and uncoupled model simulations that in northwest North America the winter cooling was primarily a remote response to climate fluctuations in the tropical Pacific. By contrast, in central North America the winter cooling appears to have resulted from a relatively rare fluctuation in mid-latitude circulation that was unrelated to the tropical Pacific. Our results highlight how decadal climate signals--both remote and local in origin--can together offset anthropogenic warming to produce continental-scale cooling.

  2. Insight into the Pacific Sea Surface Temperature- North American Hydroclimate Connection from an Eastern Tropical North Pacific Coral Record

    Science.gov (United States)

    Sanchez, S. C.; Charles, C. D.; Carriquiry, J. D.

    2015-12-01

    The last few years of record-breaking climate anomalies across North America--a resilient atmospheric ridge and extreme drought over the West Coast, and severe winters across the Midwest and East Coast regions--have been linked to anomalous Pacific sea surface temperatures (Seager et al. 2014, Wang et al. 2014, Hartmann 2015). The synoptic associations prompt important questions on the relation between these unusual phenomena and extreme expressions of known Pacific decadal modes, such as the North Pacific Gyre Oscillation (NPGO). These questions motivate our pursuit to document multiple realizations of decadal variability in the Pacific-North American region through periods of varied radiative forcing. Here we introduce a 178 year, seasonally resolved Porites coral record from Clarion Island (18N, 115W), the westernmost island of the Revillagigedo Archipelago, a region both highly influenced by NPGO SST and SSS variability and critical for NPGO tropical-extratropical communication via the Seasonal Footprinting Mechanism (Vimont et al. 2003). When coupled with tree ring records from the western United States (Griffin and Anchukaitis 2014, MacDonald and Case 2005) and coral records from the central tropical Pacific (Cobb et al. 2001), the δ18O signal from the Clarion coral offers an extended framework of coherent continental hydroclimate and oceanic variability across the Pacific basin beyond the instrumental record. Over the last 200 years, we find clear commonality in the timing, magnitude and spatial expression of variability (illustrated through the NADA Atlas, Cook et al. 2004) amongst the proxy records. The strong relationship between Northeastern Pacific Clarion and the Central Pacific Palmyra record with the North American hydroclimate records can be viewed within the mechanistic framework of the NPGO; this framework is then explored over the last millennium across intervals of varied radiative forcing.

  3. Legacy and contemporary persistent organic pollutants in North Pacific albatross.

    Science.gov (United States)

    Harwani, Suhash; Henry, Robert W; Rhee, Alexandra; Kappes, Michelle A; Croll, Donald A; Petreas, Myrto; Park, June-Soo

    2011-11-01

    Here we report the first measurements of polybrominated diphenyl ethers (PBDE 47, 99, and 153) alongside 11 organochlorine pesticides (OCPs) and 28 polychlorinated biphenyls (PCBs) in the plasma of albatross from breeding colonies distributed across a large spatial east-west gradient in the North Pacific Ocean. North Pacific albatross are wide-ranging, top-level consumers that forage in pelagic regions of the North Pacific Ocean, making them an ideal sentinel species for detection and distribution of marine contaminants. Our work on contaminant burdens in albatross tissue provides information on transport of persistent organic pollutants (POPs) to the remote North Pacific and serves as a proxy for regional environmental quality. We sampled black-footed (Phoebastria nigripes; n = 20) and Laysan albatross (P. immutabilis; n = 19) nesting on Tern Island, Hawaii, USA, and Laysan albatross (n = 16) nesting on Guadalupe Island, Mexico. Our results indicate that North Pacific albatross are highly exposed to both PCBs and OCPs, with levels ranging from 8.8 to 86.9 ng/ml wet weight and 7.4 to 162.3 ng/ml wet weight, respectively. A strong significant gradient exists between Laysan albatross breeding in the Eastern Pacific, having approximately 1.5-fold and 2.5-fold higher levels for PCBs and OCPs, respectively, compared to those from the Central Pacific. Interspecies levels of contaminants within the same breeding site also showed high variation, with Tern black-footed albatross having approximately threefold higher levels of both PCBs and OCPs than Tern Laysan albatross. Surprisingly, while PBDEs are known to travel long distances and bioaccumulate in wildlife of high trophic status, we detected these three PBDE congeners only at trace levels ranging from not detectable (ND) to 0.74 ng/ml wet weight in these albatross. PMID:21898564

  4. North Pacific sea ice cover, a predictor for the Western North Pacific typhoon frequency?

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The relationship between the sea ice cover in the North Pacific and the typhoon frequency has been studied in this paper. It follows that the index for the sea ice cover in the North Pacific (ISA) both in December-January-February (DJF) and in March-April-May (MAM) is negatively correlated with annual typhoon number over the western North Pacific (TNWNP) during 1965―2004, with correlation coeffi-cients of -0.42 and -0.49 respectively (above 99% significant level). Large sea ice cover in the North Pacific tends to decrease TNWNP. Positive ISA (MAM) is associated with the tropical circulation and SST anomalies in the North Pacific, which may lead to unfavorable dynamic and thermal conditions for typhoon genesis over WNP from June to October (JJASO). The variability of the atmospheric circula-tion over the North Pacific, associated with the ISA anomaly in MAM is connected to the tropical at-mospheric circulation variability in MAM via the teleconnection wave train. Besides, as the tropical circulation has strong seasonal persistency from the MAM to JJASO, thus, the ISA in MAM-related variability of the tropical atmospheric circulation as well as the SST can affect the typhoon activity over the western North Pacific.

  5. North Pacific sea ice cover, a predictor for the Western North Pacific typhoon frequency?

    Institute of Scientific and Technical Information of China (English)

    FAN Ke

    2007-01-01

    The relationship between the sea ice cover in the North Pacific and the typhoon frequency has been studied in this paper. It follows that the index for the sea ice cover in the North Pacific (ISA) both in December-January-February (DJF) and in March-April-May (MAM) is negatively correlated with annual typhoon number over the western North Pacific (TNWNP) during 1965-2004, with correlation coefficients of -0.42 and -0.49 respectively (above 99% significant level). Large sea ice cover in the North Pacific tends to decrease TNWNP. Positive ISA (MAM) is associated with the tropical circulation and SST anomalies in the North Pacific, which may lead to unfavorable dynamic and thermal conditions for typhoon genesis over WNP from June to October (JJASO). The variability of the atmospheric circulation over the North Pacific, associated with the ISA anomaly in MAM is connected to the tropical atmospheric circulation variability in MAM via the teleconnection wave train. Besides, as the tropical circulation has strong seasonal persistency from the MAM to JJASO, thus, the ISA in MAM-related variability of the tropical atmospheric circulation as well as the SST can affect the typhoon activity over the western North Pacific.

  6. Analysis of ''echo sounding'' data North-Central Pacific (including R/V VEMA marine geology/geophysics cruise in the North Pacific). Progress report, July 1, 1975--May 15, 1976. [Geophysical surveys in North Pacific

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, D.E.; Moody, R.

    1976-01-01

    Marine geological and geophysical data have been collated and synthesized for the area in the North Pacific bounded by 29/sup 0/N and 31/sup 0/N; 156/sup 0/W and 160/sup 0/W. Particular emphasis has been given to assessing the disposition of the sediment blanket and underlying crystalline basement (layer 2) through the examination of a variety of seismic observations. In July 1975 a 15-day cruise aboard R/V VEMA focused on the collection of a suite of piston cores, heat-flow measurements, high and low frequency seismic profiling, wide angle seismic reflection/refraction using sonobuoys, special near-bottom seismic experiments bathymetric measurements, special heat-transfer experiments, and a variety of complementary marine geological and geophysical observations. The preliminary results of the cruise and their interpretation in the framework of other existing data is summarized.

  7. Dynamics of the Central American Pacific

    Science.gov (United States)

    Vieytez, Begonia; Marrero-Díaz, Ángeles; José Machín, Francisco; José Gavidia, Francisco; Castro, Mi

    2014-05-01

    The Central American Pacific (CAP) is the area located in front of the Central America coast, within the Eastern Tropical Pacific region (ETP). The CAP dynamic is strongly influenced by the NE and SE trade winds, also this area is characterized by the presence of coastal wind jets at Gulf of Papagayo and Gulf of Panama, which are product of wind pulses blowing through the mountain gaps of the central cordillera, generating important eddies as the cyclonic eddy of Costa Rica Dome (CRD). Nevertheless, the implications of the topography of the continental margin of Central America in the determination of the dynamic processes in the area related to the action of winds and currents are still unknown. Between November and December 2010 (dry season), onboard the R/V Miguel Oliver, oceanographic parameters were measured in the CAP area, which despite its importance, has been poorly investigated until date. Available oceanographic information was processed in order to describe the dynamic along the Pacific coast of Central America, which is notable for its particularly strong stratification in the water column and the distribution of properties, as response to the presence of areas with high temperatures (above 28° C) and other areas with salinity minimum (less than 24). In this study was possible to distinguish three hydrographic zones: PM, south, in the adjacent region to Gulf of Panama, PY, in the center, in the adjacent region to Gulf of Papagayo, and FC, to the north, in the adjacent region to Gulf of Fonseca. The surface transformations of the water bodies, from south to north, observed in these zones could be indicting the presence of Costa Rica current. The prevailing wind system is the main force of variations in the surface distribution of the temperature in the area, and they are responsible of important structures as the anticyclonic eddy in front Gulf of Fonseca, eddies derived from the wind pulses of Gulf of Papagayo, and the relatively low temperatures in

  8. 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

    International Nuclear Information System (INIS)

    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

  9. The isotopic signature of fallout plutonium in the North Pacific

    International Nuclear Information System (INIS)

    Plutonium analyses of a dated coral record from the French Frigate Shoals in the central North Pacific indicate that there are two major sources of Pu in this basin: close-in (tropospheric) fallout from nuclear weapons testing at the Pacific Proving Grounds in the Marshall Islands in the 1950s and global (stratospheric) fallout which peaked in 1962. Furthermore, the 240Pu/239Pu atom ratio of fallout from the Pacific Proving Grounds is characteristically higher (0.24) than that of global fallout Pu (0.18-0.19). Seawater and sediment samples from the North Pacific exhibit a wide range of 240Pu/239Pu values (0.19-0.34), with a trend towards higher ratios in the subsurface waters and sediment. Deep water 240Pu/239Pu ratios are higher in the vicinity of the Marshall Islands relative to stations further from this close-in fallout source. These preliminary data suggest that fallout Pu from the Pacific Proving Grounds is more rapidly removed from the surface waters than is global fallout Pu. Plutonium geochemistry appears to be related to the physical/chemical form of Pu-bearing particles generated by different fallout sources. (author)

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

    OpenAIRE

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

    2015-01-01

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

  11. [Costa Rica mangroves: the north Pacific].

    Science.gov (United States)

    Zamora-Trejos, Priscilla; Cortés, Jorge

    2009-09-01

    Costa Rica has mangrove forests on both the Caribbean and Pacific coasts. The Pacific side has 99% of the mangrove area of the country. In this review we compile available information on the mangroves of the north Pacific coast of Costa Rica, from Bahía Salinas, on the border with Nicaragua, to the tip of the Peninsula de Nicoya at Cabo Blanco. We provide information on the location of the mangroves and all available information for each mangrove forest. These mangrove communities are smaller in extension and tree sizes, and have lower diversity compared to the mangroves on the southern section of the Pacific coast of Costa Rica. The dominant species are Rhizophora mangle and Rhizophora racemosa along the canal edges, backed by Avicennia germinans, and farther inland Avicennia bicolor, Laguncularia racemosa and Conocarpus erectus. At Potrero Grande a healthy population of Pelliciera rhizophorae, a rare species, has been reported. We recognized 38 mangrove communities in this part of the country, based on the National Wetland Inventory, published papers, field observations, theses, technical reports, and the national topographic maps (1:50,000, Instituto Geográfico Nacional). Relatively detailed information could be found for only five mangrove forests, for 14 more only prelimary and incomplete lists of plants and in some cases of animal species are available, for nine there is even less information, and for nine more only their location is known, which in some cases was not correct. Detail mapping, characterization of the vegetation and fauna, physiological studies, analyses of biogeochemical and physical processes, economic valuations, and determination of the health status of the mangrove of the northern Pacific coast, as well as for the rest of Costa Rica, are neccesary and urgent. PMID:19928448

  12. Shore-based counts of the Eastern North Pacific gray whale stock from central California conducted from 1967-12-18 to 2007-02-22 (NCEI Accession 0138007)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Marine Fisheries Service (NMFS) has conducted shore-based counts of the Eastern North Pacific stock of gray whales (Eschrichtius robustus) 26 years...

  13. Climate Prediction Center (CPC) East Pacific/ North Pacific Teleconnection Pattern Index

    Data.gov (United States)

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

  14. North America and Asia Pacific LNG markets

    International Nuclear Information System (INIS)

    The liquefied natural gas (LNG) export opportunities in the Asia Pacific market were reviewed. Some of the differences that affect a North American LNG projects compared to more typical LNG projects were also outlined. The two main aspects of the LNG market in North America include the establishment of LNG import terminals on the east and southern coasts of the United States and the development of export oriented LNG projects. The Pac-Rim LNG project calls for initial delivery to South Korea of 4.0 MTPA by the end of 2000. A large LNG project has also been proposed for the year 2005 which would use Prudhoe Bay gas. Generally, in North America, there is little use for large scale LNG import projects because of the vast pipeline network that delivers gas reliably and at low cost anywhere in North America. However, LNG remains a good alternative for the Asia Pacific region because of the lack of a pipeline network. Also, Japan, Korea and Taiwan, the three main centers for LNG demand, have no domestic energy supplies and rely on imported energy sources. China is another major market opportunity for LNG. The Pac-Rim LNG project differs from others of its kind in that usually, an LNG project is based on the availability of large reservoirs of natural gas owned by state governments and involves production agreements with multi-national oil and gas companies. This scenario is simply not possible in Canada's deregulated environment. In contrast, the existence of upstream facilities, technical expertise, and low capital costs, hence reduced risks and time to develop an LNG project, gives Canada significant advantages. 3 tabs., 3 figs

  15. Denali Ice Core Record of North Pacific Sea Surface Temperatures and the Pacific Decadal Oscillation

    Science.gov (United States)

    Polashenski, D.; Osterberg, E. C.; Winski, D.; Ferris, D. G.; Kreutz, K. J.; Wake, C. P.; Introne, D.

    2015-12-01

    Ice cores collected from high elevation alpine glaciers in the Alaska Range provide a unique opportunity to investigate changes in the regional climate of southern Alaska and the north Pacific over the past millennium. In this study, we seek to investigate changes in sea surface temperature (SST) in the north-central Pacific Ocean using the deuterium excess (d-excess) record from the Mt. Hunter ice cores collected in Denali National Park, Alaska. A collaborative research team from Dartmouth College and the Universities of Maine and New Hampshire collected two parallel ice cores to bedrock (208 m long) in May-June 2013 from the Mt. Hunter summit plateau (63º N, 151º W, 4,000 m above sea level). The cores were melted on a continuous melter system in the Dartmouth ice core lab and then analyzed for concentrations of major ions and trace elements, as well as stable water isotope ratios. The depth-age scale of the cores was determined using annual layer counting of δ18O and the concentrations of Mg, NH4, and Methanesulfonic acid (MSA) obtained by ion chromatography. The depth-age scale was validated using large, well-dated volcanic eruptions and the spike in 137Cs concentrations associated with nuclear weapons testing in 1963. Preliminary analyses indicate that the full record spans the past millennium. Analysis of the isotope data set extending back to 1938 using reanalysis data shows a positive correlation (p<0.05) between d-excess at the core site and the north-central Pacific SST. The north-central Pacific region of positive SST-d-excess correlation occurs at one node of the Pacific Decadal Oscillation (PDO), and thus the Denali cores are sensitive to PDO variability with low (high) d-excess associated with positive (negative) PDO index values. We also note a significant (p<0.05) declining trend in d-excess from 1938-2012, which we hypothesize to represent a rising proportion of Arctic moisture sources influencing Denali as Arctic temperatures and evaporation

  16. The History, Present Condition, and Future of the Molluscan Fisheries of North and Central America and Europe: Volume 2, Pacific Coast and Supplemental Topics

    OpenAIRE

    MacKenzie, Jr., Clyde L.; Burrell, Jr. , Victor G.; Rosenfield, Aaron; Hobart, Willis L.

    1997-01-01

    Over 100 molluscan species are landed in Mexico. About 30% are harvested on the Pacific coast and 70% on the Atlantic coast. Clams, scallops, and squid predominate on the Pacific coast (abalone, limpets, and mussels are landed there exclusively). Conchs and oysters predominate on the Atlantic coast. In 1988, some 95,000 metric tons (t) of mollusks were landed, with a value of $33 million. Mollusks were used extensively in prehispanic Mexico as food, tools, and jewelry. Their use as food an...

  17. Extreme winds in the Western North Pacific

    DEFF Research Database (Denmark)

    Ott, Søren

    2006-01-01

    A statistical model for extreme winds in the western North Pacific is developed, the region on the Planet where tropical cyclones are most common. The model is based on best track data derived mostly from satellite images of tropical cyclones. The methodsused to estimate surface wind speeds from...... they are at least coherent over time in their imperfections. Applying the the Holland model to the best track data, wind profiles can be assigned along the tracks. Fromthis annual wind speed maxima at any particular point in the region can be derived. The annual maxima, in turn, are fitted to a Gumbel distribution...... using a generalization Abild’s method that allows for data wind collected from multiple positions. Thechoice of this method is justified by a Monte Carlo simulation comparing it to two other methods. The principle output is a map showing fifty year winds in the region. The method is tested against...

  18. Central Equatorial Pacific Experiment (CEPEX). Design document

    Energy Technology Data Exchange (ETDEWEB)

    1993-04-01

    The Earth`s climate has varied significantly in the past, yet climate records reveal that in the tropics, sea surface temperatures seem to have been remarkably stable, varying by less than a few degrees Celsius over geologic time. Today, the large warm pool of the western Pacific shows similar characteristics. Its surface temperature always exceeds 27{degree}C, but never 31{degree}C. Heightened interest in this observation has been stimulated by questions of global climate change and the exploration of stabilizing climate feedback processes. Efforts to understand the observed weak sensitivity of tropical sea surface temperatures to climate forcing has led to a number of competing ideas about the nature of this apparent thermostat. Although there remains disagreement on the processes that regulate tropical sea surface temperature, most agree that further progress in resolving these differences requires comprehensive field observations of three-dimensional water vapor concentrations, solar and infrared radiative fluxes, surface fluxes of heat and water vapor, and cloud microphysical properties. This document describes the Central Equatorial Pacific Experiment (CEPEX) plan to collect such observations over the central equatorial Pacific Ocean during March of 1993.

  19. A decadal precession of atmospheric pressures over the North Pacific

    Science.gov (United States)

    Anderson, Bruce T.; Gianotti, Daniel J. S.; Furtado, Jason C.; Di Lorenzo, Emanuele

    2016-04-01

    Sustained droughts over the Northwestern U.S. can alter water availability to the region's agricultural, hydroelectric, and ecosystem service sectors. Here we analyze decadal variations in precipitation across this region and reveal their relation to the slow (~10 year) progression of an atmospheric pressure pattern around the North Pacific, which we term the Pacific Decadal Precession (PDP). Observations corroborate that leading patterns of atmospheric pressure variability over the North Pacific evolve in a manner consistent with the PDP and manifest as different phases in its evolution. Further analysis of the data indicates that low-frequency fluctuations of the tropical Pacific Ocean state energize one phase of the PDP and possibly the other through coupling with the polar stratosphere. Evidence that many recent climate variations influencing the North Pacific/North American sector over the last few years are consistent with the current phase of the PDP confirms the need to enhance our predictive understanding of its behavior.

  20. Invasive range expansion by the Humboldt squid, Dosidicus gigas, in the eastern North Pacific

    OpenAIRE

    Zeidberg, Louis D.; Robison, Bruce H.

    2007-01-01

    A unique 16-year time series of deep video surveys in Monterey Bay reveals that the Humboldt squid, Dosidicus gigas, has substantially expanded its perennial geographic range in the eastern North Pacific by invading the waters off central California. This sustained range expansion coincides with changes in climate-linked oceanographic conditions and a reduction in competing top predators. It is also coincident with a decline in the abundance of Pacific hake, the most important commercial grou...

  1. Abundance and ecological implications of microplastic debris in the North Pacific Subtropical Gyre

    OpenAIRE

    Goldstein, Miriam Chanita

    2012-01-01

    Plastic pollution in the North Pacific Subtropical Gyre (NPSG), dubbed the "Great Pacific Garbage Patch," has been the subject of substantial public concern. However, there is relatively limited scientific understanding of how microplastic affects pelagic ecosystems. The motivation for this dissertation is to provide scientific information on the extent and impact of microplastic in the NPSG. The dissertation is organized around two central questions : 1) What are the abundance, distribution,...

  2. Analysis of echo sounding data North-Central Pacific (and west North Atlantic). Final technical report, September 1, 1976--March 31, 1978. [Site selection for marine disposal of high-level radioactive wastes

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, D.E.

    1978-05-01

    Recognizing the need to consider several potentially suitable sites for disposal of high-level radioactive wastes, a very preliminary search was made through available data for such sites in the North Pacific and West North Atlantic Oceans. The criteria used were: the site must be between high-productivity belts and outside of 200 mile limit; a minimum of 50 meters of sediment, preferably 100 to 150 meters; the sediment should be red clay with minimum or no biogenic components; the sediment should contain no unconformities; and no strong discontinuous internal reflectors; the area should have no tele-seismicity, be topographically subdued, have minimal bottom currents, have no or low economical potential (Mn nodules, etc.), and be large enough (1 to 2/sup 0/ on a side) to be feasible for disposal. Some of these criteria may need to be relaxed; others may need to be added. Seismic data were the basic information used to cull out potential areas, and there are very few areas that meet the criteria as interpreted seismically. Initial site specific data assessment reported included examination of all available geophysical/geological data in and around the MPG-1 area (approximately 29/sup 0/ to 31/sup 0/N; approximately 156/sup 0/ to 160/sup 0/W); a topographic relief was described and the disposition of the thin (less than 100 m) sediment blanket and the acoustic character was mapped. A 15-day cruise was conducted in the MPG-1 area aboard the R/V VEMA and included detailed seismic measurements and heatflow/coring experiments to discern the variability of these parameters.

  3. Subtropical Air-Sea Interaction and Development of Central Pacific El Ni(n)o

    Institute of Scientific and Technical Information of China (English)

    XIE Ruihuang; HUANG Fei; REN Hongli

    2013-01-01

    The standard deviation of the central Pacific sea surface temperature anomaly (SSTA) during the period from October to February shows that the central Pacific SSTA variation is primarily due to the occurrence of the Central Pacific El Ni(n)o (CP-El Ni(n)o)and has a connection with the subtropical air-sea interaction in the northeastern Pacific.After removing the influence of the Eastern Pacific El Ni(n)o,an S-EOF analysis is conducted and the leading mode shows a clear seasonal SSTA evolving from the subtropical northeastern Pacific to the tropical central Pacific with a quasi-biennial period.The initial subtropical SSTA is generated by the wind speed decrease and surface heat flux increase due to a north Pacific anomalous cyclone.Such subtropical SSTA can further influence the establishment of the SSTA in the tropical central Pacific via the wind-evaporation-SST (WES) feedback.After established,the central equatorial Pacific SSTA can be strengthened by the zonal advective feedback and thermocline feedback,and develop into CP-El Ni(n)o.However,as the thermocline feedback increases the SSTA cooling after the mature phase,the heat flux loss and the reversed zonal advective feedback can cause the phase transition of CP-El Ni(n)o.Along with the wind stress variability,the recharge (discharge) process occurs in the central (eastern) equatorial Pacific and such a process causes the phase consistency between the thermocline depth and SST anomalies,which presents a contrast to the original recharge/discharge theory.

  4. Dust storm in Asia continent and its bio-environmental effects in the North Pacific: A case study of the strongest dust event in April, 2001 in central Asia

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Testing the effects of iron fertilization in booming metabolism of microbes in North Pacific Ocean has become an important hot topic in current global climate change study. The first supportive evidence with natural iron inputs to ocean was obtained by Bishop and his colleagues at the PAPA region in North Pacific Ocean. They found a rapid increase of marine phytoplankton over North Pacific Ocean after a strong dust storm in April 2001. We demonstrate that the dust deposition flux during this dust storm period decreases exponentially with increasing distance from the dust source regions along the dust transport pathway, through integration of synoptic dynamics, changes of TOMS-AI (aerosol index) and surface PM10 values along the dust pathway and changes of particulate organic carbon and chlorophyll in surface oceans. This strong dust storm may result in deposition of about 3.1-5.8 μg/m3 eolian iron into the PAPA region in North Pacific Ocean, thus causing a rapid increase of marine phytoplankton productivity observed by Bishop and his colleagues. This work supplies more direct and detailed evidence, from continental dust process, to support the iron hypothesis with natural iron inputs to the surface oceans through dust storms.

  5. 75 FR 53951 - North Pacific Fishery Management Council; Public Meetings

    Science.gov (United States)

    2010-09-02

    ... Council;s Gulf of Alaska (GOA) and Bering Sea/Aleutian Islands (BS/AI) Groundfish Plan Teams will meet in... (GOA Plan Team) and Traynor Room (BS/AI Plan Team), Seattle, WA. Council address: North Pacific...

  6. Status of marine mammals in the eastern North Pacific Ocean

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report covers the status or marine mammals in the eastern north Pacific Ocean. Species covered are: sea otter, northern, Guadalupe fur seals, stellar,...

  7. Invasive range expansion by the Humboldt squid, Dosidicus gigas, in the eastern North Pacific.

    Science.gov (United States)

    Zeidberg, Louis D; Robison, Bruce H

    2007-07-31

    A unique 16-year time series of deep video surveys in Monterey Bay reveals that the Humboldt squid, Dosidicus gigas, has substantially expanded its perennial geographic range in the eastern North Pacific by invading the waters off central California. This sustained range expansion coincides with changes in climate-linked oceanographic conditions and a reduction in competing top predators. It is also coincident with a decline in the abundance of Pacific hake, the most important commercial groundfish species off western North America. Recognizing the interactive effects of multiple changes in the environment is an issue of growing concern in ocean conservation and sustainability research. PMID:17646649

  8. Dynamic Mechanism of Interannual Sea Surface Height Variability in the North Pacific Subtropical Gyre

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yong-Chui; ZHANG Li-Feng; L(U) Qing-Ping

    2011-01-01

    In this study, the dynamic mechanisms of interannual sea surface height (SSH) variability are investigated based on the first-mode baroclinic Rossby wave model, with a focus on the effects of different levels of wind stress curl (WSC)、 Maximum covariance analysis (MCA) of WSC and SSH anomalies displays a mode with significant WSC anomalies located primarily in the mid-latitude eastern North Pacific and central tropical Pacific with corresponding SSH anomalies located to the west. This leading mode can be attributed to Ekman pumping induced by local wind stress and the westward-propagating Rossby wave driven by largescale wind stress. It is further found that in the middle latitudes, the SSH anomalies are largely determined by WSC variations associated with the North Pacific Gyre Oscillation (NPGO)、 rather than the Pacific Decadal Oscillation (PDO). The sensitivity of the predictive skill of the linear first-mode baroclinic model to different wind products is also examined.

  9. Preliminary result of dissolved organic radiocarbon in the western North Pacific Ocean

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Takayuki, E-mail: tanaka.takayuki@jaea.go.j [AMS Management Section, Japan Atomic Energy Agency, 4-24 Minatomachi, Mutsu, Aomori 035-0064 (Japan); Otosaka, Shigeyoshi [Research Group for Environmental Science, Japan Atomic Energy Agency, 2-4 Shirakata-Shirane, Tokai, Ibaraki 319-1195 (Japan); Wakita, Masahide [Mutsu Institute for Oceanography, Japan Agency for Marine-Earth Science and Technology, 690 Kitasekine, Sekine, Mutsu, Aomori 035-0022 (Japan); Amano, Hikaru [Japan Chemical Analysis Center, 293-5 Sanno-cho, Inage-ku, Chiba-shi 263-0002 (Japan); Togawa, Orihiko [Research Group for Environmental Science, Japan Atomic Energy Agency, 2-4 Shirakata-Shirane, Tokai, Ibaraki 319-1195 (Japan)

    2010-04-15

    Radiocarbon in dissolved organic matter in seawater gives information on the dynamics and origin of the dissolved organic matter. Here, we present the vertical profile of DELTA{sup 14}C of dissolved organic carbon in the western North Pacific Ocean. The profile was almost parallel to that for DELTA{sup 14}C of dissolved inorganic carbon, indicating that the time scale of seawater circulation was the main influence on the DELTA{sup 14}C signature of dissolved organic carbon. On the basis of the DELTA{sup 14}C differences between dissolved organic carbon and dissolved inorganic carbon, and a comparison with DELTA{sup 14}C of dissolved organic carbon in the central North Pacific Ocean, we suggest that there may be a source of younger dissolved organic carbon in the western North Pacific Ocean.

  10. Identification of CO2 disposal locations in an ocean general circulation model of the North Pacific

    Institute of Scientific and Technical Information of China (English)

    XU Yongfu; AOKI Shigeaki; HARADA Koh

    2009-01-01

    A basin-wide ocean general circulation model of the North Pacific is used to identify which location is more effi-cient for ocean CO2 sequestration in the North Pacific. Four injection depths at each one of fifteen locations are chosen. In terms of effectiveness index (EI) and escape factor (EF), it is clear that the effectiveness increases with increasing latitude at the end of the 50 a injection period. Site-by-site differences in the EI can be over 9% for the 1 000 m injection depth in the western North Pacific at the end of 50 a of continuous injection. The difference is much larger for the 500 m injection. The difference decreases with increasing injection depth. However, the site-by-site difference is small for the injection in the eastern North Pacific. The sequestration is more efficient for the injection in the east than in the west. For the 500 m injection depth, the difference in ef-fectiveness between the west and the east is over 10% at the end of 50 a injection period. The largest concentra-tion of sequestered CO2 increases with increasing injection depth. For the injection in both the western and cen-tral North Pacific, the largest exchange flux always appears to be at about 42°N, 150°E, whereas for the injec-tion in the eastern area the large flux appears to be in the equatorial region (120°W).

  11. Extreme winds in the Western North Pacific

    Energy Technology Data Exchange (ETDEWEB)

    Ott, S.

    2006-11-15

    A statistical model for extreme winds in the western North Pacific is developed, the region on the Planet where tropical cyclones are most common. The model is based on best track data derived mostly from satellite images of tropical cyclones. The methods used to estimate surface wind speeds from satellite images is discussed with emphasis on the empirical basis, which, unfortunately, is not very strong. This is stressed by the fact that Japanese and US agencies arrive at markedly different estimates. On the other hand, best track data records cover a long period of time and if not perfect they are at least coherent over time in their imperfections. Applying the the Holland model to the best track data, wind profiles can be assigned along the tracks. From this annual wind speed maxima at any particular point in the region can be derived. The annual maxima, in turn, are fitted to a Gumbel distribution using a generalization Abild's method that allows for data wind collected from multiple positions. The choice of this method is justified by a Monte Carlo simulation comparing it to two other methods. The principle output is a map showing fifty year winds in the region. The method is tested against observed winds from Philippine synoptic stations and fair agreement is found for observed and predicted 48 year maxima. However, the almost biasfree performance of the model could be fortuitous, since precise definitions of 'windspeed' in terms averaging time, height above ground and assumed surface roughness are not available, neither for best tracks nor for the synoptic data. The work has been carried out under Danish Research Agency grant 2104-04-0005 'Offshore wind power' and it also covers the findings and analysis carried out in connection with task 1.6 of the project 'Feasibility Assessment and Capacity Building for Wind Energy Development in Cambodia, The Philippines and Vietnam' during 2005-06 under contract 125-2004 with EU

  12. Paleoceanography of the Eastern Tropical North Pacific on millennial timescales

    OpenAIRE

    Arellano-Torres, Elsa

    2010-01-01

    The occurrence of large scale and rapid climate shifts at millennial time-scales (suborbital) remains an enigma between records from high and low latitudes spanning the Late Quaternary. This thesis studies such variations in the eastern tropical North Pacific (ETNP) using marine sediment cores retrieved from Mexico and Nicaragua. The main goals are to understand the nature of millennial timescale climate-changes in the Pacific low latitudes, to identify the atmospheric and ocea...

  13. Conservation of native Pacific trout diversity in western North America

    Science.gov (United States)

    Penaluna, Brooke E.; Abadía-Cardoso, Alicia; Dunham, Jason; García de León, Francisco J; Gresswell, Robert E.; Luna, Arturo Ruiz; Taylor, Eric B.; Shepard, Bradley B.; Al-Chokhachy, Robert K.; Muhlfeld, Clint C.; Bestgen, Kevin R.; Rogers, Kevin H.; Escalante, Marco A; Keeley, Ernest R; Temple, Gabriel; Williams, Jack E.; Matthews, Kathleen; Pierce, Ron; Mayden, Richard L.; Kovach, Ryan; Garza, John Carlos; Fausch, Kurt D.

    2016-01-01

    Pacific trout Oncorhynchus spp. in western North America are strongly valued in ecological, socioeconomic, and cultural views, and have been the subject of substantial research and conservation efforts. Despite this, the understanding of their evolutionary histories, overall diversity, and challenges to their conservation is incomplete. We review the state of knowledge on these important issues, focusing on Pacific trout in the genus Oncorhynchus. Although most research on salmonid fishes emphasizes Pacific salmon, we focus on Pacific trout because they share a common evolutionary history, and many taxa in western North America have not been formally described, particularly in the southern extent of their ranges. Research in recent decades has led to the revision of many hypotheses concerning the origin and diversification of Pacific trout throughout their range. Although there has been significant success at addressing past threats to Pacific trout, contemporary and future threats represented by nonnative species, land and water use activities, and climate change pose challenges and uncertainties. Ultimately, conservation of Pacific trout depends on how well these issues are understood and addressed, and on solutions that allow these species to coexist with a growing scope of human influences.

  14. Fossil Overlapping Spreading Centre in the Central Pacific at the Trace of the Pacific-Cocos-Nazca Triple Point

    Science.gov (United States)

    Meschede, M.; Barckhausen, U.; Weinrebe, W.; Engels, M.

    2005-12-01

    The Central Pacific region between 125° W/5° N and 110° W/10° S which contains the "plate tectonic mirror image" to the region of the Cocos plate currently being subducted beneath Central America has been the target of an investigation using multibeam bathymetry, magnetics and gravity. One of the main points of interest was the formation of the triple junction of Pacific, Cocos and Nacza plates in the Late Oligocene/Early Miocene (around 24 Myrs). This event indicates the breakup of the Farallon plate on the eastern side of the East-Pacific-Rise into Cocos and Nazca plates. At this time the first Cocos-Nazca spreading centre (CNS-1) a precursor of the currently active spreading centre (CNS-3) between Cocos and Nazca plates was initiated. The breakup process is a result of changing spreading directions caused by global changes in plate movement directions. This is documented in the area of investigation in the Central Pacific in changes in the strike direction of magnetic lineations from north to south and morphological structures of the seafloor. Irregularities in the magnetic lineation pattern in a small area in the centre of the investigation area and curved morphological structures on the oceanic seafloor are interpreted in terms of remnants of a fossil overlapping spreading centre. The overlapping spreading centre was formed as a consequence of shiftings in the spreading axis which subsequently are straightened out by processes like the one described.

  15. 77 FR 59901 - North Pacific Fishery Management Council; Public Meeting

    Science.gov (United States)

    2012-10-01

    ... potential management measures, using the status quo management measures of one fish less than 45 inches or... National Oceanic and Atmospheric Administration RIN 0648-XC259 North Pacific Fishery Management Council... Management Council (Council) Charter Management Implementation Committee will convene via a conference...

  16. 78 FR 70018 - North Pacific Fishery Management Council; Public Meeting

    Science.gov (United States)

    2013-11-22

    ... fish with a maximum size limit; and (4) Status quo management of one fish less than 45 inches or greater than 68 inches. For Regulatory Area 3A: (1) Status quo management of a bag limit of two fish, with... National Oceanic and Atmospheric Administration RIN 0648-XC990 North Pacific Fishery Management...

  17. 76 FR 13360 - North Pacific Fishery Management Council; Public Meetings

    Science.gov (United States)

    2011-03-11

    .../approve salmon excluder EFP; review discussion paper on AFA impacts on Bering Sea cod trawlers. 10. Staff... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE... Hotel, 500 West 3rd Avenue, Anchorage, AK. Council address: North Pacific Fishery Management...

  18. Diversity of Pseudo-nitzschia from the western North Pacific

    DEFF Research Database (Denmark)

    Stonik, Inna V; Orlova, Tatiana Yu; Lundholm, Nina

    2011-01-01

    Asurvey focusing on species belonging to the diatom genus Pseudo-nitzschia was conducted in the western North Pacific (the northwestern Sea of Japan and the Sea of Okhotsk). Light and electron microscopic examination of 314 phytoplankton field samples collected from 1995 to 2006 revealed the pres...

  19. Impact of the central Pacific zonal wind divergence and convergence on the central Pacific El Niño event

    Institute of Scientific and Technical Information of China (English)

    ZUO Tao; CHEN Jinnian; WANG Hongna

    2014-01-01

    The central Pacific (CP) zonal wind divergence and convergence indices are defined, and the forming mech-anism of CP El Niño (La Niña) events is discussed preliminarily. The results show that the divergence and convergence of the zonal wind anomaly (ZWA) are the key process in the forming of CP El Niño (La Niña) events. A correlation analysis between the central Pacific zonal wind divergence and convergence indices and central Pacific El Niño indices indicates that there is a remarkable lag correlation between them. The central Pacific zonal wind divergence and convergence indices can be used to predict the CP events. Based on these results, a linear regression equation is obtained to predict the CP El Niño (La Niña) events 5 months ahead.

  20. 78 FR 4835 - Endangered and Threatened Species; Recovery Plan for the North Pacific Right Whale

    Science.gov (United States)

    2013-01-23

    ... Plan for the North Pacific Right Whale AGENCY: National Marine Fisheries Service, National Oceanic and... Plan (Plan) for the North Pacific right whale (Eubalaena japonica). NMFS is soliciting review and... West Highway, Silver Spring, MD 20910, Attn: North Pacific Right Whale Recovery Plan. Instructions:...

  1. Diet and Ecomorphology of the Sandpaper Skate, Bathyraja kincaidii (Garman, 1908) from the Eastern North Pacific

    OpenAIRE

    Rinewalt, Christopher S.

    2007-01-01

    To determine diet, the stomach contents of sandpaper skates, Bathyraja kincaidii (Garman, 1908), were examined from a limited depth and geographic area off central California and from a wider depth and area range along the eastern North Pacific (ENP). The overall diet was dominated by euphausiids and shrimps, but polychaetes, squids, and gammarid amphipods were important secondary prey. Shrimp-like crustaceans, polychaetes, and teleosts were of similar importance in both data sources, but sma...

  2. Causes of decadal climate variability over the North Pacific and North America

    International Nuclear Information System (INIS)

    The cause of decadal climate variability over the North Pacific and North America is investigated by analyzing data from a multi-decadal integration with a state of the art coupled ocean-atmosphere model and observations. About one third of the low-frequency climate variability in the region of interest can be attributed to a cycle involving unstable air-sea interactions between the subtropical gyre circulation in the North Pacific and the Aleutian low pressure system. The existence of this cycle provides a basis for long-range climate forecasting over the western United States at decadal time scales. (orig.)

  3. Nutrient Concentrations collected from OSCAR ELTON SETTE in North Pacific Ocean from 2008-03-01 to 2011-04-30

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Laboratory analysis of water samples collected aboard the NOAA Ship Oscar Elton Sette along a 158W transect from 26-36N in the central North Pacific. Laboratory...

  4. The probability of tropical cyclone landfalls in Western North Pacific

    Science.gov (United States)

    Bonazzi, A.; Bellone, E.; Khare, S.

    2012-04-01

    The Western North Pacific (WNP) is the most active basin in terms of tropical cyclone and typhoon occurrences. The densely populated countries that form the western boundary of WNP basin -- e.g. China, Japan and the Philippines -- are exposed to extreme wind gusts, storm surge and fresh water flooding eventually triggered by Tropical Cyclones (TC) events. Event-based catastrophe models (hereafter cat models) are extensively used by the insurance industry to manage their exposure against low-frequency/high-consequence events such as natural catastrophes. Cat models provide their users with a realistic set of stochastic events that expands the scope of a historical catalogue. Confidence in a cat model ability to extrapolate peril and loss statistics beyond the period covered by observational data requires good agreement between stochastic and historical peril characteristics at shorter return periods. In WNP risk management practitioners are faced with highly uncertain data to base their decisions. Albeit 4 national agencies maintain best track catalogues, data are generally based on satellite imageries with very limited central pressure (CP) and maximum velocity (VMAX) measurements -- regular flight reconnaissance missions stopped in 1987. As a result differences up to 20 knots are found in estimates of VMAX from different agencies as documented in experiment IOP-10 during Typhoon Megi in 2010. In this work we present a comprehensive analysis of CP and VMAX probability distributions at landfall across the WNP basin along a set of 150 gates (100 km coast segments) based on best track catalogues from Japan Meteorological Agency, Joint Typhoon Warning Center, China Meteorological Agency and Hong Meteorological Agency. Landfall distributions are then used to calibrate a random-walk statistical track model. A long simulation of 100,000 years of statistical TC tracks will ultimately constitute the central building block of a basin-wide stochastic catalogue of synthetic TC

  5. Dynamic Linkage between the North Pacific and the Tropical Pacific: Atmosphere-Ocean Coupling

    Institute of Scientific and Technical Information of China (English)

    LI Chun; WU Lixin

    2013-01-01

    In this study,dynamic linkage of atmosphere-ocean coupling between the North Pacific and the tropical Pacific was demonstrated using a large number of ensemble perturbed initial condition experiments in a fully coupled fast ocean-atmosphere model (FOAM).In the FOAM model,an idealized mixed layer warming was initiated in the Kuroshio-Oyashio extension region,while the ocean and atmosphere remained fully coupled both locally and elsewhere.The modeling results show that the warm anomalies are associated with anomalous cyclonic winds,which induce initial warming anomalies extending downstream in the following winter.Then,the downstream warming spreads southwestward and induces SST warming in the equatorial Pacific via surface wind-evaporation-SST feedback.Warming in the tropical Pacific is further reinforced by Bjerknes' feedback.

  6. Regime Shifts in the North Pacific Simulated by a COADS-driven Isopycnal Model

    Institute of Scientific and Technical Information of China (English)

    王东晓; 王佳; 吴立新; 刘征宇

    2003-01-01

    The Miami Isopycnal Coordinate Ocean Model (MICOM) is adopted to simulate the interdecadalvariability in the Pacific Ocean with most emphasis on regime shifts in the North Pacific. The compu-tational domain covers 60°N to 40°S with an enclosed boundary condition for momentum flux, whereasthere are thermohaline fluxes across the southern end as a restoring term. In addition, sea surface salinityof the model relaxes to the climatological season cycle, which results in climatological fresh water fluxes.Surface forcing functions from January 1945 through December 1993 are derived from the ComprehensiveOcean and Atmospheric Data Set (COADS). Such a numerical experiment reproduces the observed evo-lution of the interdecadal variability in the heat content over the upper 400-m layer by a two-year lag.Subduction that occurs at the ventilated thermocline in the central North Pacific is also been simulatedand the subducted signals propagate from 35°N to 25°N, taking about 8 to 10 years, in agreement with theeXpendable Bathy Thermograph observation over recent decades. Interdecadal signals take a southwest-ward and downward path rather than westward propagation, meaning they are less associated with thebaroclinic planetary waves. During travel, the signals appear to conserve potential vorticity. Therefore,the ventilated thermocline and related subduction are probably the fundamental physics for interdecadalvariability in the mid-latitude subtropics of the North Pacific.

  7. THE LICHENS OF NORTH CENTRAL OKLAHOMA

    Directory of Open Access Journals (Sweden)

    DARVIN WENDELL KECK

    2006-12-01

    Full Text Available Over 1,000 specimens of lichens were collected at 78 collecting stations in 11 counties of North Central Oklahoma during 1959 and 1960. The objectives were to identify lichens collected in the area; to establish a record of lichen distribution for each county in the area; and to analyze the ecological relationships.

  8. Fluctuation in Ommastrephe bartrami yield in the North Pacific

    Institute of Scientific and Technical Information of China (English)

    ZHENG Rui; CHEN Ge

    2008-01-01

    The fluctuation in Ommastrephe bartrami yield from 1995 to 2001 in the North Pacific was shown obvious, on which this study was conducted using data of sea surface temperature (SST), chlorophyll-a (chl-a) and statistical production. The study shows that, cool water and low food abundance caused by abnormal Kuroshio resulted in the reduction in abundance of O. bartrami, which was worsened by excessive catch and the unawareness to local fishery resources protection.

  9. Hazardous chemicals in marine mammals from the western North Pacific

    International Nuclear Information System (INIS)

    Marine mammals have long-term life and occupy the highest ecological niche in the marine ecosystem. Thus, higher concentration of hazardous chemicals are expected in marine mammals. In the present study, we review contamination of organochlorine compounds (DDTs, PCBs, HCHs, etc.), heavy metals (Hg, Cd, Pb, etc.) and butyltin (TBT, DBT and MBT) in marine mammals collected from the western North Pacific, and discuss the worldwide contamination of these chemicals

  10. Heat and salt transport throughout the North Pacific Ocean

    Science.gov (United States)

    Yang, Lina; Yuan, Dongliang

    2016-03-01

    Absolute geostrophic currents in the North Pacific Ocean are calculated using the P-vector method and gridded Argo profiling data from January 2004 to December 2012. Three-dimensional structures and seasonal variability of meridional heat transport (MHT) and meridional salt transport (MST) are analyzed. The results show that geostrophic and Ekman components are generally opposite in sign, with the southward geostrophic component dominating in the subtropics and the northward Ekman component dominating in the tropics. In combination with the net surface heat flux and the MST through the Bering Strait, the MHT and MST of the western boundary currents (WBCs) are estimated for the first time. The results suggest that the WBCs are of great importance in maintaining the heat and salt balance of the North Pacific. The total interior MHT and MST in the tropics show nearly the same seasonal variability as that of the Ekman components, consistent with the variability of zonal wind stress. The geostrophic MHT in the tropics is mainly concentrated in the upper layers, while MST with large amplitude and annual variation can extend much deeper. This suggests that shallow processes dominate MHT in the North Pacific, while MST can be affected by deep ocean circulation. In the extratropical ocean, both MHT and MST are weak. However, there is relatively large and irregular seasonal variability of geostrophic MST, suggesting the importance of the geostrophic circulation in the MST of that area.

  11. Spatial segregation in eastern North Pacific skate assemblages.

    Science.gov (United States)

    Bizzarro, Joseph J; Broms, Kristin M; Logsdon, Miles G; Ebert, David A; Yoklavich, Mary M; Kuhnz, Linda A; Summers, Adam P

    2014-01-01

    Skates (Rajiformes: Rajoidei) are common mesopredators in marine benthic communities. The spatial associations of individual species and the structure of assemblages are of considerable importance for effective monitoring and management of exploited skate populations. This study investigated the spatial associations of eastern North Pacific (ENP) skates in continental shelf and upper continental slope waters of two regions: central California and the western Gulf of Alaska. Long-term survey data were analyzed using GIS/spatial analysis techniques and regression models to determine distribution (by depth, temperature, and latitude/longitude) and relative abundance of the dominant species in each region. Submersible video data were incorporated for California to facilitate habitat association analysis. We addressed three main questions: 1) Are there regions of differential importance to skates?, 2) Are ENP skate assemblages spatially segregated?, and 3) When skates co-occur, do they differ in size? Skate populations were highly clustered in both regions, on scales of 10s of kilometers; however, high-density regions (i.e., hot spots) were segregated among species. Skate densities and frequencies of occurrence were substantially lower in Alaska as compared to California. Although skates are generally found on soft sediment habitats, Raja rhina exhibited the strongest association with mixed substrates, and R. stellulata catches were greatest on rocky reefs. Size segregation was evident in regions where species overlapped substantially in geographic and depth distribution (e.g., R. rhina and Bathyraja kincaidii off California; B. aleutica and B. interrupta in the Gulf of Alaska). Spatial niche differentiation in skates appears to be more pronounced than previously reported. PMID:25329312

  12. Spatial segregation in eastern North Pacific skate assemblages.

    Directory of Open Access Journals (Sweden)

    Joseph J Bizzarro

    Full Text Available Skates (Rajiformes: Rajoidei are common mesopredators in marine benthic communities. The spatial associations of individual species and the structure of assemblages are of considerable importance for effective monitoring and management of exploited skate populations. This study investigated the spatial associations of eastern North Pacific (ENP skates in continental shelf and upper continental slope waters of two regions: central California and the western Gulf of Alaska. Long-term survey data were analyzed using GIS/spatial analysis techniques and regression models to determine distribution (by depth, temperature, and latitude/longitude and relative abundance of the dominant species in each region. Submersible video data were incorporated for California to facilitate habitat association analysis. We addressed three main questions: 1 Are there regions of differential importance to skates?, 2 Are ENP skate assemblages spatially segregated?, and 3 When skates co-occur, do they differ in size? Skate populations were highly clustered in both regions, on scales of 10s of kilometers; however, high-density regions (i.e., hot spots were segregated among species. Skate densities and frequencies of occurrence were substantially lower in Alaska as compared to California. Although skates are generally found on soft sediment habitats, Raja rhina exhibited the strongest association with mixed substrates, and R. stellulata catches were greatest on rocky reefs. Size segregation was evident in regions where species overlapped substantially in geographic and depth distribution (e.g., R. rhina and Bathyraja kincaidii off California; B. aleutica and B. interrupta in the Gulf of Alaska. Spatial niche differentiation in skates appears to be more pronounced than previously reported.

  13. 75 FR 68756 - Eastern North Pacific Gray Whale; Notice of Petition Availability

    Science.gov (United States)

    2010-11-09

    ... National Oceanic and Atmospheric Administration RIN 0648-XA018 Eastern North Pacific Gray Whale; Notice of... Pacific population of gray whales (Eschrichtius robustus) as a depleted stock under the Marine Mammal... assessment report for Eastern North Pacific gray whales is available on the Internet at the following...

  14. CRED 20 m Gridded bathymetry of Johnston Atoll, Pacific Remote Island Areas, Central Pacific (Arc ASCII Format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry (20 m cell size) of the shelf and slope environments of Johnston Atoll, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  15. CRED 5 m Gridded bathymetry of Baker Island, Pacific Remote Island Areas, Central Pacific (NetCDF Format)

    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 Baker Island, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  16. CRED 5 m Gridded bathymetry of Howland Island, Pacific Remote Island Areas, Central Pacific (NetCDF Format)

    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 Howland Island, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  17. CRED 40 m Gridded bathymetry of Palmyra Atoll, Pacific Remote Island Areas, Central Pacific (Arc ASCII Format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (40 m cell size) bathymetry of the lagoon, shelf and slope environments of Palmyra Atoll, Pacific Remote Island Areas, Central Pacific. Almost complete...

  18. CRED 5 m Gridded bathymetry of Jarvis Island, Pacific Remote Island Areas, Central Pacific (Arc ASCII Format)

    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 Jarvis Island, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  19. CRED 5 m Gridded bathymetry of Palmyra Atoll, Pacific Remote Island Areas, Central Pacific (NetCDF Format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (5 m cell size) bathymetry of the lagoon, shelf and slope environments of Palmyra Atoll, Pacific Remote Island Areas, Central Pacific. Almost complete...

  20. CRED 40 m Gridded bathymetry of Howland Island, Pacific Remote Island Areas, Central Pacific (Arc ASCII Format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (40 m cell size) bathymetry of the shelf and slope environments of Howland Island, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  1. CRED 5 m Gridded bathymetry of Johnston Atoll, Pacific Remote Island Areas, Central Pacific (Arc ASCII Format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry (5 m cell size) of the shelf and slope environments of Johnston Atoll, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  2. CRED 20 m Gridded bathymetry of Jarvis Island, Pacific Remote Island Areas, Central Pacific (Arc ASCII Format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (20 m cell size) bathymetry of the shelf and slope environments of Jarvis Island, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  3. CRED 40 m Gridded bathymetry of Howland Island, Pacific Remote Island Areas, Central Pacific (NetCDF Format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (40 m cell size) bathymetry of the shelf and slope environments of Howland Island, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  4. CRED 40 m Gridded bathymetry of Baker Island, Pacific Remote Island Areas, Central Pacific (Arc ASCII Format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (40 m cell size) bathymetry of the shelf and slope environments of Baker Island, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  5. CRED 20 m Gridded bathymetry of Johnston Atoll, Pacific Remote Island Areas, Central Pacific (NetCDF Format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry (20 m cell size) of the shelf and slope environments of Johnston Atoll, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  6. CRED 5 m Gridded bathymetry of Baker Island, Pacific Remote Island Areas, Central Pacific (Arc ASCII Format)

    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 Baker Island, Pacific Remote Isand Areas, Central Pacific. Almost complete bottom coverage...

  7. CRED 5 m Gridded bathymetry of Jarvis Island, Pacific Remote Island Areas, Central Pacific (NetCDF Format)

    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 Jarvis Island, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  8. CRED 5 m Gridded bathymetry of Howland Island, Pacific Remote Island Areas, Central Pacific (Arc ASCII Format)

    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 Howland Island, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  9. CRED 5 m Gridded bathymetry of Johnston Atoll, Pacific Remote Island Areas, Central Pacific (NetCDF Format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry (5 m cell size) of the shelf and slope environments of Johnston Atoll, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  10. CRED 20 m Gridded bathymetry of Kingman Reef, Pacific Remote Island Areas, Central Pacific (Arc ASCII Format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (20 m cell size) bathymetry of the lagoon, shelf and slope environments of Kingman Reef, Pacific Remote Island Areas, Central Pacific. Almost complete...

  11. CRED 5 m Gridded bathymetry of Palmyra Atoll, Pacific Remote Island Areas, Central Pacific (Arc ASCII Format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (5 m cell size) bathymetry of the lagoon, shelf and slope environments of Palmyra Atoll, Pacific Remote Island Areas, Central Pacific. Almost complete...

  12. CRED 5 m Gridded bathymetry of Kingman Reef, Pacific Remote Island Areas, Central Pacific (NetCDF Format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (5 m cell size) bathymetry of the lagoon, shelf and slope environments of Kingman Reef, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  13. CRED 40 m Gridded bathymetry of Palmyra Atoll, Pacific Remote Island Areas, Central Pacific (NetCDF Format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (40 m cell size) bathymetry of the lagoon, shelf and slope environments of Palmyra Atoll, Pacific Remote Island Areas, Central Pacific. Almost complete...

  14. CRED 20 m Gridded bathymetry of Kingman Reef, Pacific Remote Island Areas, Central Pacific (NetCDF Format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (20 m cell size) bathymetry of the lagoon, shelf and slope environments of Kingman Reef, Pacific Remote Island Areas, Central Pacific. Almost complete...

  15. CRED 5 m Gridded bathymetry of Kingman Reef, Pacific Remote Island Areas, Central Pacific (Arc ASCII Format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (5 m cell size) bathymetry of the lagoon, shelf and slope environments of Kingman Reef, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  16. CRED Reson 8101 multibeam backscatter data of Jarvis Island, Pacific Remote Island Areas, Central Pacific in netCDF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of the shelf and slope environments of Jarvis Atoll, Pacific Island Areas, Central Pacific. These...

  17. CRED Reson 8101 multibeam backscatter data of Jarvis Island, Pacific Remote Island Areas, Central Pacific in GeoTIFF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of the shelf and slope environments of Jarvis Atoll, Pacific Island Areas, Central Pacific. These...

  18. CRED Reson 8101 multibeam backscatter data of Howland Island, Pacific Remote Island Areas, Central Pacific in GeoTIFF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of the shelf and slope environments of Howland Atoll, Pacific Island Areas, Central Pacific. These...

  19. Summertime Subtropical Countercurrent on isopycnals in the western North Pacific

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Circulations on isopycnals (σrθ) in the western North Pacific were investigated by using P-vector method;the data were taken from the U.S. Navy's climatological temperature and salinity dataset (public domain) with 1/2°×1/2° resolution. Results not only show the main circulation systems on isopycnals in the western North Pacific such as the North Equatorial Current (NEC), Kuroshio and Kuroshio Countercurrent, but also reveal the Subtropical Countercurrent (STCC) clearly. In this note we pay attention to discussing the distribution of STCC in summer (in June).The STCC flows eastward along a winding road; on shallow isopycnals, the STCC originates from the area east of Bashi Strait at about 122.5°E; with the isopycnals increasing, the origin and flow core of STCC move to north and east, but the main part of STCC is still between 18° and 23.5°N, i.e.near the Tropic of Cancer. There exists STCC on all isopycnals between the sea surface and 25.8 σθThe current vectors of STCC on isopycnais are shown for the first time, and the distribution of the potential vorticity indicates that STCC is just overlying the southern boundary of the Subtropical Mode Water (STMW).``

  20. Attributing the causes of North Pacific oxygen change

    Science.gov (United States)

    Deutsch, C.; Emerson, S.; Thompson, L.

    2004-12-01

    We investigate the variability of dissolved oxygen in the upper water column of the North Pacific using a hind cast model simulation. The model applies the biogeochemical framework of the Ocean Carbon Model Intercomparison Project (OCMIP) to an isopycnal General Circulation Model (GCM) whose circulation is forced at the surface by historical atmospheric conditions from 1948-2000. Simulated O2 changes from the 1980's to the 1990's include O2 decreases in the subpolar region, especially in the lower ventilated thermocline, and O2 increases over much of the subtropics. Both of these features are similar in pattern and magnitude to those observed along repeat transects through the subtropical and subpolar gyres [Emerson et al. 2004]. We perform a set of additional simulations designed to separate the contributions of changes in biology, ventilation, and circulation to O2 variability. We find that the direct effect of circulation variability, including a southward expansion of the subtropical gyre, is the dominant cause of O2 changes over much of the North Pacific. Variations in thermocline ventilation lead to significant O2 decreases in the Subarctic Northwest Pacific, and the impact of changes in biological export production are confined to the upper thermocline. Simulated O2 changes involve both long-term trends, such as the decreased Subarctic O2 due to reduced ventilation, as well as transient responses to short-term perturbations, many of which occurred in the 1970's.

  1. AFSC/RACE/GAP/Conrath: Delayed discard mortality of the North Pacific giant octopus

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The majority of octopus bycatch occurs in Pacific cod pot fisheries and recent data collected by North Pacific Groundfish Observers indicate that immediate...

  2. An interdecadal change in the relationship between January-March Arctic Oscillation and North Pacific Precipitation

    Science.gov (United States)

    Hu, Miao

    2014-05-01

    An analysis of variability in the relationships between the winter (January-March) Arctic Oscillation and precipitation over the Northern Pacific during the period of 1979 to 2011 is presented based on the monthly precipitation data (CMAP) and NCEP/NCAR Reanalysis, after subtracting ENSO signals from all datasets. The sliding correlation analysis demonstrates there is a prominent weakening in the AO-precipitation relation around the early 1990s. In the total 33 years a high (low) AO phase more likely accompanies with a stronger (weaker) precipitation in the subtropical Pacific, and the mainly significant correlation area ranges from 10°-30°N,150°E-190°W. During the year 1979 to 1989, the positive correlations over the tropical Pacific are significant and widely-ranged; however, the correlations weaken over the whole region and even negative over the central Pacific after the early 1990s. In addition, the Model BCCR-BCM2 is capable of simulating the correct overall AO-precipitation relation over North Pacific.

  3. Seasonal variation of the surface North Equatorial Countercurrent (NECC) in the western Pacific Ocean

    Science.gov (United States)

    Zhao, Jun; Li, Yuanlong; Wang, Fan

    2016-03-01

    The North Equatorial Countercurrent (NECC) is an important zonal flow in the upper circulation of the tropical Pacific Ocean, which plays a vital role in the heat budget of the western Pacific warm pool. Using satellite-derived data of ocean surface currents and sea surface heights (SSHs) from 1992 to 2011, the seasonal variation of the surface NECC in the western tropical Pacific Ocean was investigated. It was found that the intensity (INT) and axis position (Y CM) of the surface NECC exhibit strikingly different seasonal fluctuations in the upstream (128°-136°E) and downstream (145°-160°E) regions. Of the two regions, the seasonal cycle of the upstream NECC shows the greater interannual variability. Its INT and YCM are greatly influenced by variations of the Mindanao Eddy, Mindanao Dome (MD), and equatorial Rossby waves to its south. Both INT and Y CM also show semiannual signals induced by the combined effects of equatorial Rossby waves from the Central Pacific and local wind forcing in the western Pacific Ocean. In the downstream region, the variability of the NECC is affected by SSH anomalies in the MD and the central equatorial Pacific Ocean. Those in the MD region are especially important in modulating the YCM of the downstream NECC. In addition to the SSH-related geostrophic flow, zonal Ekman flow driven by meridional wind stress also plays a role, having considerable impact on INT variability of the surface NECC. The contrasting features of the variability of the NECC in the upstream and downstream regions reflect the high complexity of regional ocean dynamics.

  4. Geographic variation in Pacific herring growth in response to regime shifts in the North Pacific Ocean

    Science.gov (United States)

    Ito, Shin-ichi; Rose, Kenneth A.; Megrey, Bernard A.; Schweigert, Jake; Hay, Douglas; Werner, Francisco E.; Aita, Maki Noguchi

    2015-11-01

    Pacific herring populations at eight North Pacific Rim locations were simulated to compare basin-wide geographic variations in age-specific growth due to environmental influences on marine productivity and population-specific responses to regime shifts. Temperature and zooplankton abundance from a three-dimensional lower-trophic ecosystem model (NEMURO: North Pacific Ecosystem Model for Understanding Regional Oceanography) simulation from 1948 to 2002 were used as inputs to a herring bioenergetics growth model. Herring populations from California, the west coast of Vancouver Island (WCVI), Prince William Sound (PWS), Togiak Alaska, the western Bering Sea (WBS), the Sea of Okhotsk (SO), Sakhalin, and Peter the Great Bay (PGB) were examined. The half-saturation coefficients of herring feeding were calibrated to climatological conditions at each of the eight locations to reproduce averaged size-at-age data. The depth of averaging used for water temperature and zooplankton, and the maximum consumption rate parameter, were made specific to each location. Using the calibrated half-saturation coefficients, the 1948-2002 period was then simulated using daily values of water temperature and zooplankton densities interpolated from monthly model output. To detect regime shifts in simulated temperatures, zooplankton and herring growth rates, we applied sequential t-test analyses on the 54 years of hindcast simulation values. The detected shifts of herring age-5 growth showed closest match (69%) to the regime shift years (1957/58, 1970/71, 1976/77, 1988/89, 1998/99). We explored relationships among locations using cluster and principal component analyses. The first principal component of water temperature showed good correspondence to the Pacific Decadal Oscillation and all zooplankton groups showed a pan-Pacific decrease after the 1976/77 regime shift. However, the first principal component of herring growth rate showed decreased growth at the SO, PWS, WCVI and California

  5. North Pacific Eastern Subtropical Mode Water simulation and future projection

    Institute of Scientific and Technical Information of China (English)

    XIA Ruibin; LIU Qinyu; XU Lixiao; LU Yiqun

    2015-01-01

    The present climate simulation and future projection of the Eastern Subtropical Mode Water (ESTMW) in the North Pacific are investigated based on the Geophysical Fluid Dynamics Laboratory Earth System Model (GFDL-ESM2M). Spatial patterns of the mixed layer depth (MLD) in the eastern subtropical North Pacific and the ESTMW are well simulated using this model. Compared with historical simulation, the ESTMW is produced at lighter isopycnal surfaces and its total volume is decreased in the RCP8.5 runs, because the subduction rate of the ESTMW decreases by 0.82×10−6 m/s during February–March. In addition, it is found that the lateral induction decreasing is approximately four times more than the Ekman pumping, and thus it plays a dominant role in the decreased subduction rate associated with global warming. Moreover, the MLD during February–March is banded shoaling in response to global warming, extending northeastward from the east of the Hawaii Islands (20°N, 155°W) to the west coast of North America (30°N, 125°W), with a max-imum shoaling of 50 m, and then leads to the lateral induction reduction. Meanwhile, the increased north-eastward surface warm current to the east of Hawaii helps strengthen of the local upper ocean stratification and induces the banded shoaling MLD under warmer climate. This new finding indicates that the ocean surface currents play an important role in the response of the MLD and the ESTMW to global warming.

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

    Science.gov (United States)

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

    2015-10-01

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

  7. Scale interaction between typhoons and the North Pacific subtropical high and associated remote effects during the Baiu/Meiyu season

    Science.gov (United States)

    Hirata, Hidetaka; Kawamura, Ryuichi

    2014-05-01

    The interaction between typhoons and the North Pacific subtropical high and the associated remote impact on East Asian and North Pacific anomalous weather during the Baiu/Meiyu season have been investigated using the Japanese long-term Reanalysis project data aided by the Japan Meteorological Agency Climate Data Assimilation System. The typhoons that appeared in July have been categorized into two primary tracks, the Hainan Island course (HC) and the Okinawa Island course (OC). A typhoon gives rise to negative absolute vorticity advection along its eastern periphery, which locally reinforces the western ridge of the North Pacific subtropical high, whereas the resultant anomalous high stimulates the westward (northward) migration of the HC (OC) typhoon through its combination with the background flow. A combined effect of the typhoon and its induced anomalous anticyclonic circulation increases the transportation of moisture into the Baiu/Meiyu frontal zone in the vicinity of Japan. Over the East China Sea and the Sea of Japan, northward or northeastward moisture flux is pronounced along the western periphery of the typhoon-induced anticyclonic circulation anomaly in the HC category, triggering heavy rainfall on central Japan's Sea of Japan coast. Similar remote effects also operate in the OC category, which is responsible for the occurrence of extremely heavy rainfall along the Pacific coast of western Japan. When an OC typhoon approaches the Asian jet, it is capable of giving rise to anticyclonic vorticity within the jet, leading to the downstream development of stationary Rossby wave packets via the North Pacific waveguide.

  8. The plastic-associated microorganisms of the North Pacific Gyre

    International Nuclear Information System (INIS)

    Highlights: • Microorganisms mediate processes affecting the fate and impacts of marine plastic. • North Pacific Gyre (NPG) plastics were examined with scanning-electron microscopy. • Bacillus bacteria and pennate diatoms dominated the NPG plastic fouling community. • Bacterial abundance was patchily distributed but increased on foamed polystyrene. • Diatom abundance increased on rough surfaces and at sites with high plastic density. -- Abstract: Microorganisms likely mediate processes affecting the fate and impacts of marine plastic pollution, including degradation, chemical adsorption, and colonization or ingestion by macroorganisms. We investigated the relationship between plastic-associated microorganism communities and factors such as location, temperature, salinity, plankton abundance, plastic concentration, item size, surface roughness, and polymer type. Small plastic items from the surface of the North Pacific Gyre in 2011 were examined using scanning electron microscopy. Bacillus bacteria (mean 1664 ± 247 individuals mm−2) and pennate diatoms (1097 ± 154 mm−2) were most abundant, with coccoid bacteria, centric diatoms, dinoflagellates, coccolithophores, and radiolarians present. Bacterial abundance was patchy, but increased on foamed polystyrene. Diatom abundance increased on items with rough surfaces and at sites with high plastic concentrations. Morphotype richness increased slightly on larger fragments, and a biogeographic transition occurred between pennate diatom groups. Better characterizing this community will aid in understanding how it interacts with plastic pollution

  9. North Pacific seasonality and the glaciation of North America 2.7 million years ago

    OpenAIRE

    Haug, G. H.; Ganopolski, A.; Sigman, D. M.; Rosell-Mele, A.; G. E. A. Swann; R. Tiedemann; S. L. Jaccard; J. Bollmann; Maslin, M. A.; Leng, M. J.; Eglinton, G.;  ,

    2005-01-01

    In the context of gradual Cenozoic cooling, the timing of the onset of significant Northern Hemisphere glaciation 2.7 million years ago is consistent with Milankovitch’s orbital theory, which posited that ice sheets grow when polar summertime insolation and temperature are low. However, the role of moisture supply in the initiation of large Northern Hemisphere ice sheets has remained unclear. The subarctic Pacific Ocean represents a significant source of water vapour to boreal North America, ...

  10. Aerobic Anoxygenic Phototrophic Bacteria in the Mid-Atlantic Bight and the North Pacific Gyre. Revised

    Science.gov (United States)

    Cottrell, Matthew T.; Mannino, Antonio; Kirchman, David L.

    2005-01-01

    The abundance of aerobic anoxygenic phototrophic (AM) bacteria, cyanobacteria and heterotrophs was examined in the Mid-Atlantic Bight and the central North Pacific gyre using infrared fluorescence microscopy coupled with image analysis and flow cytometry. AAP bacteria comprised 5% to 16% of total prokaryotes in the Atlantic but only 5% or less in the Pacific. In the Atlantic, AAP bacterial abundance was as much as 2-fold higher than Prochlorococcus and 10-folder higher than Synechococcus. In contrast, Prochlorococcus outnumbered AAP bacteria 5- to 50-fold in the Pacific. In both oceans, subsurface abundance maxima occurred within the photic zone, and AAP bacteria were least abundant below the 1% light depth. Concentrations of bacteriochlorophyll a (BChl a) were low (approx.1%) compared to chlorophyll a. Although the BChl a content of AAP bacteria per cell was typically 20- to 250-fold lower than the divinyl-chlorophyll a content of Prochlorococcus, in shelf break water the pigment content of AAP bacteria approached that of Prochlorococcus. The abundance of AAP bacteria rivaled some groups of strictly heterotrophic bacteria and was often higher than the abundance of known AAP genera (Erythrobacter and Roseobacter spp.). The distribution of AAP bacteria in the water column, which was similar in the Atlantic and the Pacific, was consistent with phototrophy.

  11. 50 CFR 226.215 - Critical habitat for the North Pacific Right Whale (Eubalaena japonica).

    Science.gov (United States)

    2010-10-01

    ... Right Whale (Eubalaena japonica). 226.215 Section 226.215 Wildlife and Fisheries NATIONAL MARINE... DESIGNATED CRITICAL HABITAT § 226.215 Critical habitat for the North Pacific Right Whale (Eubalaena japonica). (a) Primary Constituent Elements. The primary constituent elements of the North Pacific right...

  12. The influence of boreal winter extratropical North Pacific Oscillation on Australian spring rainfall

    Science.gov (United States)

    Song, Linye; Li, Yun; Duan, Wansuo

    2016-08-01

    The North Pacific Oscillation (NPO) is a key atmospheric intrinsic mode. This study concerns mechanisms that the NPO influences Southern Hemisphere climate anomalies after several months. It is found that the boreal wintertime NPO has a significant negative connection with austral spring rainfall anomalies in Australia, particularly in the Northern Territory, Queensland, New South Wales and Victoria. A positive NPO phase tends to be followed by dry conditions, while a negative phase by wet conditions in austral spring over much of northern and eastern Australia. The physical mechanism by which the boreal winter NPO affects Australian rainfall arises from the NPO seasonal footprinting mechanism that generates significant tropical central and eastern Pacific sea surface temperature (SST) warming anomalies during austral spring. Then, the positive NPO-related SST warming anomalies over the tropical central-eastern Pacific further induce a weakened Walker circulation, with its western subsiding branch over Australia, suppressing convection and thereby reducing rainfall. Furthermore, the NPO plays an important role in contributing to the significant long-term trends of the Northern Territory and Queensland rainfalls. The decreasing amplitude of the NPO contributes much of the observed rainfall wetting trends in the Northern Territory (~50 %) and Queensland (~60 %) regions during 1951-2010. Noted that caution is recommended regarding the Australian spring rainfall trend results obtained in this study as the austral spring rainfall trends may be sensitive to the choice of the selected time period.

  13. Final Report for UW-Madison Portion of DE-SC0005301, "Collaborative Project: Pacific Decadal Variability and Central Pacific Warming El Niño in a Changing Climate"

    Energy Technology Data Exchange (ETDEWEB)

    Vimont, Daniel [University of Wisconsin - Madison

    2014-06-13

    This project funded two efforts at understanding the interactions between Central Pacific ENSO events, the mid-latitude atmosphere, and decadal variability in the Pacific. The first was an investigation of conditions that lead to Central Pacific (CP) and East Pacific (EP) ENSO events through the use of linear inverse modeling with defined norms. The second effort was a modeling study that combined output from the National Center for Atmospheric Research (NCAR) Community Atmospheric Model (CAM4) with the Battisti (1988) intermediate coupled model. The intent of the second activity was to investigate the relationship between the atmospheric North Pacific Oscillation (NPO), the Pacific Meridional Mode (PMM), and ENSO. These two activities are described herein.

  14. Orbital control of the western North Pacific summer monsoon

    Science.gov (United States)

    Wu, Chi-Hua; Chiang, John C. H.; Hsu, Huang-Hsiung; Lee, Shih-Yu

    2016-02-01

    Orbital forcing exerts a strong influence on global monsoon systems, with higher summer insolation leading to stronger summer monsoons in the Northern Hemisphere. However, the associated regional and seasonal changes, particularly the interaction between regional monsoon systems, remain unclear. Simulations using the Community Earth System Model demonstrate that the western North Pacific (WNP) summer monsoon responds to orbital forcing opposite to that of other major Northern Hemisphere monsoon systems. Compared with its current climate state, the simulated WNP monsoon and associated lower-tropospheric trough is absent in the early Holocene when the precession-modulated Northern Hemisphere summer insolation is higher, whereas the summer monsoons in South and East Asia are stronger and shift farther northward. We attribute the weaker WNP monsoon to the stronger diabatic heating of the summer Asian monsoon—in particular over the southern Tibetan Plateau and Maritime Continent—that in turn strengthens the North Pacific subtropical high through atmospheric teleconnections. By contrast, the impact of the midlatitude circulation changes on the WNP monsoon is weaker when the solar insolation is higher. Prior to the present WNP monsoon onset, the upper-tropospheric East Asian jet stream weakens and shifts northward; the monsoon onset is highly affected by the jet-induced high potential vorticity intrusion. In the instance of the extreme perihelion-summer, the WNP monsoon is suppressed despite a stronger midlatitude precursor than present-day, and the midlatitude circulation response to the enhanced South Asian precipitation is considerable. These conditions indicate internal monsoon interactions of an orbital scale, implying a potential mechanistic control of the WNP monsoon.

  15. WATER TEMPERATURE and DEPTH - SENSOR collected from NOAA Ship OSCAR ELTON SETTE in Hawaii EEZ, central North Pacific Ocean, and others from 2010-04-20 to 2010-04-30 (NCEI Accession 0155915)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — XBT data were collected during a Pacific Islands Fisheries Science Center's Cetacean Research Program's shipboard cetacean survey (Cruise ID: SE 10-04). XBT casts...

  16. WATER TEMPERATURE and DEPTH - SENSOR collected from NOAA Ship OSCAR ELTON SETTE in Hawaii EEZ, central North Pacific Ocean, and others from 2010-01-22 to 2010-02-06 (NCEI Accession 0155913)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — XBT data were collected during a Pacific Islands Fisheries Science Center's Cetacean Research Program's shipboard cetacean survey (Cruise ID SE 10-01). XBT casts...

  17. WATER TEMPERATURE, DISSOLVED OXYGEN, and others collected from OSCAR ELTON SETTE in Hawaii EEZ, central North Pacific Ocean, and others from 2010-04-20 to 2010-04-30 (NCEI Accession 0155996)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — CTD data were collected during a Pacific Islands Fisheries Science Center's Cetacean Research Program's shipboard cetacean survey (Cruise ID: SE 10-04). A total of...

  18. Soil indigenous knowledge in North Central Namibia

    Science.gov (United States)

    Prudat, Brice; Bloemertz, Lena; Kuhn, Nikolaus J.

    2016-04-01

    Mapping and classifying soils is part of an important learning process to improve soil management practices, soil quality and increase productivity. In order to assess soil quality improvement related to an ongoing land reform in North-Central Namibia, the characteristics that determine soil quality in the local land use context were determined in this study. To do so, we collated the indigenous soil knowledge in North-Central Namibia where the Ovakwanyama cultivate pearl millet for centuries. Local soil groups are defined mostly based on their productivity potential, which varies depending on the rainfall pattern. The morphological criteria used by the farmers to differentiate the soil groups (colour, consistence) were supported by a conventional analysis of soil physical and chemical properties. Now, they can be used to develop a soil quality assessment toolbox adapted to the regional use. The characteristics of the tool box do not directly indicate soil quality, but refer to local soils groups. The quality of these groups is relatively homogenous at the local scale. Our results show that understanding of indigenous soil knowledge has great potential to improve soil quality assessment with regards to land use. The integration of this knowledge with the conventional soil analysis improves the local meaning of such a "scientific" assessment and thus facilitates dialog between farmers and agronomists, but also scientists working in different regions of the world, but in similar conditions. Overall, the integration of indigenous knowledge in international classification systems (e.g. WRB) as attempted in this study has thus a major potential to improve soil mapping in the local context.

  19. Storm track activity over the North Pacific associated with the Madden-Julian Oscillation under ENSO conditions during boreal winter

    Science.gov (United States)

    Takahashi, Chiharu; Shirooka, Ryuichi

    2014-09-01

    The present study investigates modulation by the Madden-Julian Oscillation (MJO) of storm track activity (STA) over the North Pacific (NP) during boreal winter for El Niño and La Niña periods. STA defined by vertically averaged synoptic eddy kinetic energy (EKE) greatly intensifies over the western North Pacific (WNP) and central eastern North Pacific during La Niña and El Niño years, respectively, when the MJO convection is located over the central Indian Ocean (IO)-Maritime Continent. When the MJO moves into the western central Pacific, the STA in La Niña years is suppressed (enhanced) at higher (lower) latitudes than in El Niño years. Diagnoses of EKE and eddy available potential energy budgets indicate that the difference in STA over the WNP for the MJO phases between El Niño-Southern Oscillation (ENSO) years is mainly contributed by baroclinic energy conversion and potential energy conversion between background and eddy (BCPE). We reveal that BCPE is mainly attributed to intraseasonal baroclinicity and eddy heat flux (EHF) anomalies and their interactions with strong winter mean baroclinic fields in the WNP. Through the EHF, synoptic eddies act to counterbalance an intraseasonal temperature that is primarily caused by the anomalous horizontal advection of mean temperature by MJO-related flow. The intraseasonal circulation and associated temperature and EHF anomalies dominate in northwest (southeast) portion of the NP during La Niña (El Niño), leading to BCPE difference. Changes in the spatial pattern and strength of the NP circulation and STA are caused by dominance of strong MJO amplification over the IO (central Pacific) during La Niña (El Niño).

  20. Relationships between the tropical SST and summertime subtropical high over the western North Pacific

    Science.gov (United States)

    Chung, Pei-Hsuan; Sui, Chung-Hsiung; Li, Tim

    2010-05-01

    The interannual variability of the western North Pacific Subtropical High (WNPSH) in summer is investigated with the use of the NCEP/NCAR reanalysis data for the period of 1958-2005. The most significant change appears at the western edge of WNPSH, with dominant 2-3-yr and 3-5-yr power spectrum peaks. The 2-3-yr oscillation of WNPSH and associated circulation and sea surface temperature (SST) patterns possess a coherent eastward-propagating feature, with a warm SST anomaly (SSTA) and anomalous ascending motion migrating from the tropical Indian Ocean in the preceding winter to the maritime continent in the concurrent summer of a strong WNPSH. A strong WNPSH is characterized by anomalous anticyclonic circulation and maximum subsidence in the western North Pacific (WNP). The anomalous WNPSH circulation has an equivalent barotropic vertical structure and resides in the sinking branch of local Hadley circulation, triggered by enhanced convection over the maritime continent in the summer. A heat budget analysis reveals that WNPSH is maintained by radiative cooling, which overcomes the decent induced adiabatic warming. The 3-5-yr oscillation of WNPSH exhibits a quasi stationary feature, with a warm SSTA (anomalous ascending motion) located in the equatorial central-eastern Pacific and Indian Ocean and a cold SSTA (anomalous descending motion) located in the western Pacific. The anomaly pattern persists from the preceding winter to the concurrent summer of a high WNPSH. The maximum descent is located to the east of the anomalous anticyclone center, where a baroclinic vertical structure is identified. The anomalous anticyclone on this timescale is a Rossby wave response to a negative convective heating associated with the local cold SSTA.

  1. North Central Project: Environment act proposal

    International Nuclear Information System (INIS)

    Manitoba Hydro proposes to construct a power transmission and distribution line system to connect 12 northern Manitoba communities to the utility's central power grid. The purpose of this North Central Project (NCP) is to provide reliable and unrestricted electric service to remote communities now largely receiving limited diesel-generated power. The NCP is composed of a 138-kV transmission line running ca 350 km from the Kelsey Generating Station, ca 160 km of 25-kV distribution lines, new transformer stations at four communities, upgraded internal distribution systems within the communities, removal of existing diesel stations and restoration of the sites, modifications and additions to the Kelsey switchyard, and a communications system. The NCP is described in detail, including proposed line routes and transformer station locations, rationales for site and route selection, projected impacts on the environment and local societies, and consultations with the communities to be affected. Potential impacts are expected to be modest, with few unmitigable adverse impacts and a number of potentially significant positive benefits. Impact management measures are proposed to prevent or mitigate adverse effects and to create or enhance positive impacts such as local employment of native peoples. 49 figs., 1 tab

  2. Contrasting Effects of Central Pacific and Eastern Pacific El Nino on Stratospheric Water Vapor

    Science.gov (United States)

    Garfinkel, Chaim I.; Hurwitz, Margaret M.; Oman, Luke D.; Waugh, Darryn W.

    2013-01-01

    Targeted experiments with a comprehensive chemistry-climate model are used to demonstrate that seasonality and the location of the peak warming of sea surface temperatures dictate the response of stratospheric water vapor to El Nino. In spring, El Nino events in which sea surface temperature anomalies peak in the eastern Pacific lead to a warming at the tropopause above the warm pool region, and subsequently to more stratospheric water vapor (consistent with previous work). However, in fall and in early winter, and also during El Nino events in which the sea surface temperature anomaly is found mainly in the central Pacific, the response is qualitatively different: temperature changes in the warm pool region are nonuniform and less water vapor enters the stratosphere. The difference in water vapor in the lower stratosphere between the two variants of El Nino approaches 0.3 ppmv, while the difference between the winter and spring responses exceeds 0.5 ppmv.

  3. Central-north China precipitation as reconstructed from the Qing dynasty: Signal of the Antarctic Atmospheric Oscillation

    Science.gov (United States)

    Wang, Huijun; Fan, Ke

    2005-12-01

    Based on the long-term Central-north China precipitation (CNCP) time series reconstructed from the Qing Dynasty Official Document, the relationship between CNCP and the Antarctic Atmospheric Oscillation (AAO) in June-July is examined. The analysis yields a (significant) negative correlation of -0.22. The signal of AAO in CNCP is further studied through analyses of the atmospheric general circulation variability related to AAO. It follows that AAO-related variability of convergence and convection over the tropical western Pacific can exert impact on the circulation condition and precipitation in north China (actually, the precipitation in the Yangtze River Valley as well) through atmospheric teleconnection known as the East Asia-Pacific (or Pacific-Japan) teleconnection wave pattern. There is also an AAO-connected wave train in the vorticity field at high troposphere over Eurasia, providing an anti-cyclonic circulation in central-north China favorable to the decline of precipitation in positive phase of AAO.

  4. Coastal Carbon Synthesis for the Continental Shelf of the North American Pacific Coast (NAPC)

    Science.gov (United States)

    Siedlecki, S. A.; Alin, S. R.

    2015-12-01

    The West Coast represents the longest coastline in North America, stretching from Panama all the way northward to the Aleutians. Key advances in the carbon cycling of this margin have been made since the North American Continental Margins report (Hales et al., 2008), notably the convergence of models and observations on air-sea fluxes; more sophisticated coastal carbon cycle models; and increased observational coverage in space and time, allowing for more data synthesis and model-data comparison. The coast was divided up into sub-regions based on differences in oceanographic drivers of coastal carbon cycling. Those sub-regions include the Gulf of Alaska, the Central American Isthmus, and the California Current System (CCS), which is further subdivided into northern, central, and southern sectors. The carbon budget for the Pacific Coast of North America identifies the best-known fluxes as the air-sea exchange of CO2 and terrestrial inputs. The least constrained fluxes include respiration, cross-shelf exchange, and carbon metabolism in estuaries. Spatial trends were typically consistent among models and observations, but the magnitude of the fluxes varied widely. While more modeling and observational studies exist than are presented here, relevant fluxes for the carbon budget were often unreported. In the long-term, investments in research and monitoring will be needed to better constrain the fluxes of many of the highly variable regions described in this study. In addition to the budget, this synthesis identifies gaps and priorities for future research.

  5. Influence of the Western Pacific teleconnection pattern on Western North Pacific tropical cyclone activity

    Science.gov (United States)

    Choi, Ki-Seon; Moon, Il-Ju

    2012-09-01

    This study analyzes the characteristics of Western North Pacific (WNP) tropical cyclone (TC) activity and large-scale environments according to the Western Pacific (WP) teleconnection pattern in summer. In the positive WP phase, an anomalous cyclone and an anomalous anticyclone develop in the low and middle latitudes of the East Asia area, respectively. As a result, southeasterlies are reinforced in the northeast area of East Asia (including Korea and Japan), which facilitates the movement of TC to this area, whereas northwesterlies are reinforced in the southwest area of East Asia (including southern China and the Indochina Peninsula) which blocks the movement of TC to that area. Due to the spatial distribution of this reinforced pressure system, TCs that develop during the positive WP phase move and turn more to the northeast of the WNP than TCs which develop during the negative WP phase. The characteristics of this TC activity during the positive WP phase are associated with the upper tropospheric jet being located farther to the northeast. TCs during the negative WP phase mainly move to the west from the Philippines toward southern China and the Indochina Peninsula. Due to the terrain effect caused by the passage of TCs in mainland China, the intensity of TCs during the negative WP phase is weaker than those during the positive WP phase.

  6. Trans-Pacific and trans-Arctic pathways of the intertidal macroalga Fucus distichus L. reveal multiple glacial refugia and colonizations from the North Pacific to the North Atlantic

    NARCIS (Netherlands)

    Coyer, James A.; Hoarau, Galice; Van Schaik, Jaap; Luijckx, Pepijn; Olsen, Jeanine L.

    2011-01-01

    Aim We examined the phylogeography of the cold-temperate macroalgal species Fucus distichus L., a key foundation species in rocky intertidal shores and the only Fucus species to occur naturally in both the North Pacific and the North Atlantic. Location North Pacific and North Atlantic oceans (42 deg

  7. North and equatorial Pacific Ocean circulation in the CORE-II hindcast simulations

    Science.gov (United States)

    Tseng, Yu-heng; Lin, Hongyang; Chen, Han-ching; Thompson, Keith; Bentsen, Mats; Böning, Claus W.; Bozec, Alexandra; Cassou, Christophe; Chassignet, Eric; Chow, Chun Hoe; Danabasoglu, Gokhan; Danilov, Sergey; Farneti, Riccardo; Fogli, Pier Giuseppe; Fujii, Yosuke; Griffies, Stephen M.; Ilicak, Mehmet; Jung, Thomas; Masina, Simona; Navarra, Antonio; Patara, Lavinia; Samuels, Bonita L.; Scheinert, Markus; Sidorenko, Dmitry; Sui, Chung-Hsiung; Tsujino, Hiroyuki; Valcke, Sophie; Voldoire, Aurore; Wang, Qiang; Yeager, Steve G.

    2016-08-01

    We evaluate the mean circulation patterns, water mass distributions, and tropical dynamics of the North and Equatorial Pacific Ocean based on a suite of global ocean-sea ice simulations driven by the CORE-II atmospheric forcing from 1963-2007. The first three moments (mean, standard deviation and skewness) of sea surface height and surface temperature variability are assessed against observations. Large discrepancies are found in the variance and skewness of sea surface height and in the skewness of sea surface temperature. Comparing with the observation, most models underestimate the Kuroshio transport in the Asian Marginal seas due to the missing influence of the unresolved western boundary current and meso-scale eddies. In terms of the Mixed Layer Depths (MLDs) in the North Pacific, the two observed maxima associated with Subtropical Mode Water and Central Mode Water formation coalesce into a large pool of deep MLDs in all participating models, but another local maximum associated with the formation of Eastern Subtropical Mode Water can be found in all models with different magnitudes. The main model bias of deep MLDs results from excessive Subtropical Mode Water formation due to inaccurate representation of the Kuroshio separation and of the associated excessively warm and salty Kuroshio water. Further water mass analysis shows that the North Pacific Intermediate Water can penetrate southward in most models, but its distribution greatly varies among models depending not only on grid resolution and vertical coordinate but also on the model dynamics. All simulations show overall similar large scale tropical current system, but with differences in the structures of the Equatorial Undercurrent. We also confirm the key role of the meridional gradient of the wind stress curl in driving the equatorial transport, leading to a generally weak North Equatorial Counter Current in all models due to inaccurate CORE-II equatorial wind fields. Most models show a larger

  8. Modulation of western North Pacific tropical cyclone activity by the Atlantic Meridional Mode

    Science.gov (United States)

    Zhang, Wei; Vecchi, Gabriel A.; Villarini, Gabriele; Murakami, Hiroyuki; Rosati, Anthony; Yang, Xiaosong; Jia, Liwei; Zeng, Fanrong

    2016-05-01

    This study examines the year-to-year modulation of the western North Pacific (WNP) tropical cyclones (TC) activity by the Atlantic Meridional Mode (AMM) using both observations and the Geophysical Fluid Dynamics Laboratory Forecast-oriented Low Ocean Resolution Version of CM2.5 (FLOR) global coupled model. 1. The positive (negative) AMM phase suppresses (enhances) WNP TC activity in observations. The anomalous occurrence of WNP TCs results mainly from changes in TC genesis in the southeastern part of the WNP. 2. The observed responses of WNP TC activity to the AMM are connected to the anomalous zonal vertical wind shear (ZVWS) caused by AMM-induced changes to the Walker circulation. During the positive AMM phase, the warming in the North Atlantic induces strong descending flow in the tropical eastern and central Pacific, which intensifies the Walker cell in the WNP. The intensified Walker cell is responsible for the suppressed (enhanced) TC genesis in the eastern (western) part of the WNP by strengthening (weakening) ZVWS. 3. The observed WNPTC-AMM linkage is examined by the long-term control and idealized perturbations experiment with FLOR-FA. A suite of sensitivity experiments strongly corroborate the observed WNPTC-AMM linkage and underlying physical mechanisms.

  9. Tuna longline fishing around West and Central Pacific seamounts.

    Directory of Open Access Journals (Sweden)

    Telmo Morato

    Full Text Available BACKGROUND: Seamounts have been identified as aggregating locations for pelagic biodiversity including tuna; however the topography and prevailing oceanography differ between seamounts and not all are important for tuna. Although a relatively common feature in oceanic ecosystems, little information is available that identifies those that are biologically important. Improved knowledge offers opportunities for unique management of these areas, which may advance the sustainable management of oceanic resources. In this study, we evaluate the existence of an association between seamounts and tuna longline fisheries at the ocean basin scale, identify significant seamounts for tuna in the western and central Pacific Ocean, and quantify the seamount contribution to the tuna longline catch. METHODOLOGY/PRINCIPAL FINDINGS: We use data collected for the Western and Central Pacific Ocean for bigeye, yellowfin, and albacore tuna at the ocean basin scale. GLMs were applied to a coupled dataset of longline fisheries catch and effort, and seamount location information. The analyses show that seamounts may be associated with an annual longline combined catch of 35 thousand tonnes, with higher catch apparent for yellowfin, bigeye, and albacore tuna on 17%, 14%, and 14% of seamounts respectively. In contrast 14%, 18%, and 20% of seamounts had significantly lower catches for yellowfin, bigeye and albacore tuna respectively. Studying catch data in relation to seamount positions presents several challenges such as bias in location of seamounts, or lack of spatial resolution of fisheries data. Whilst we recognize these limitations the criteria used for detecting significant seamounts were conservative and the error in identification is likely to be low albeit unknown. CONCLUSIONS/SIGNIFICANCE: Seamounts throughout the study area were found to either enhance or reduce tuna catch. This indicates that management of seamounts is important Pacific-wide, but management

  10. 75 FR 64691 - North Central Idaho Resource Advisory Committee

    Science.gov (United States)

    2010-10-20

    ... Forest Service North Central Idaho Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The North Central Idaho RAC will meet in Potlatch, Idaho. The committee is.... (PST). ADDRESSES: The meeting will be held at the Potlatch Public Library, 1010 Onaway Road,...

  11. CRED Reson 8101 multibeam backscatter data of Johnston Island, Pacific Remote Island Areas, Central Pacific in GeoTIFF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of the lagoon, shelf, and slope environments of Palmyra Atoll, Pacific Island Areas, Central...

  12. CRED Reson 8101 multibeam backscatter data of Johnston Island, Pacific Remote Island Areas, Central Pacific in netCDF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of the lagoon, shelf, and slope environments of Palmyra Atoll, Pacific Island Areas, Central...

  13. 33 CFR 3.04-3 - Pacific Area.

    Science.gov (United States)

    2010-07-01

    ....04-3 Pacific Area. (a) The Area Office is in Alameda, CA. (b) The Pacific Area is comprised of the.... longitude to the North American land mass; thence along the west coast of the North, Central, and...

  14. Seasonal Climate Associated with Major Shipping Routes in the North Pacific and North Atlantic

    Directory of Open Access Journals (Sweden)

    Jau-Ming Chen

    2014-01-01

    Full Text Available The major shipping routes in the North Pacific (NP and North Atlantic (NA are analyzed via ship-reported records compiled by the International Comprehensive Ocean-Atmosphere Data Set (ICOADS. The shipping route seasonal characteristics and associated climatic features are also examined. In the NP, the dominant cross-basin route takes a great-circle path between East Asia and North America along 54°N54°N north of the Aleutian Islands throughout the year. This route penetrates the Aleutian low center where ocean waves and winds are relatively weaker than those in the _ southern section south of 50°N.50°N. Moreover, the _ spherical shape makes a higher-latitude route shorter in navigational distance across the NP than a lower-latitude route. Two additional mid-latitude routes through the 40°40° - 50°N50°N region appear in summer when the Aleutian low vanishes. In the NA, the major shipping routes form an X-shaped pattern in the oceans south of 40°N40°N to connect North America/the Panama Canal and the Mediterranean Sea/the British Isles and Europe. These major shipping routes are far from the influence of the Icelandic low and thus are used throughout the year due to the stability in marine conditions and their general efficiency. A third and more zonal route appears to the north of the X-shaped routes in the 40°40° - 50°N50°N region. Weak influence from the Icelandic low on marine conditions during summer and spring means that more ships take this route in summer and spring than in winter and fall.

  15. Contrail properties over the eastern North Pacific from AVHRR data

    Energy Technology Data Exchange (ETDEWEB)

    Minnis, P. [Sciences Directorate, NASA Langley Research Center (United States); Palikonda, R.; Walter, B.J.; Kirk Ayers, J. [AS and M, Inc., Hampton, VA (United States); Mannstein, H. [DLR Inst. fuer Physik der Atmosphaere, Oberpfaffenhofen, Wessling (Germany)

    2005-08-01

    An increase of air traffic over the North Pacific during the last 30 years has been accompanied by an increase in cirrus coverage. To help alleviate the uncertainty in the contribution of air traffic to the cirrus increase, an analysis of linear contrail coverage over the region has been initiated using afternoon NOAA-16 AVHRR data taken during 4 months in 2002 and 2003. Manual evaluation of the automated contrail detection method revealed that it misclassified, on average, 32% of the pixels as contrails and missed 15% of the contrail pixels. After correction for detection errors, the contrail coverage over the domain between 25 and 55 N and between 120 and 150 W varied from a minimum of 0.37% in February to a maximum of 0.56% in May, respectively. The annual mean coverage, after correcting for the diurnal cycle of air traffic, is 0.31%, a value very close to earlier theoretical estimates for the region. Contrail optical depths for the 4 months average 0.24 resulting in a mean unit contrail longwave radiative forcing of 14.2 Wm{sup -2}. The contrail optical depths are twice the mean value expected from theoretical estimates. (orig.)

  16. Bifurcation of Pacific North Equatorial Current at the surface

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The grid altimetry data between 1993 and 2006 near the Philippines were analyzed by the method of Empirical Orthogonal Function (EOF) to study the variation of bifurcation of the North Equatorial Current at the surface of the Pacific. The relatively short-term signals with periods of about 6 months, 4 months, 3 months and 2 months are found besides seasonal and interannual variations mentioned in previous studies. Local wind stress curl plays an important role in controlling variation of bifurcation latitude except in the interannual timescale. The bifurcation latitude is about 13.3°N in annual mean state and it lies at the northernmost position (14.0°N) in January, at the southernmost position (12.5°N) in July. The amplitude of variation of bifurcation latitude in a year is 1.5°, which can mainly be explained as the contributions of the signals with periods of about 1 year (1.2°) and 0.5 year (0.3°).

  17. Ammonia and nitrite oxidation in the Eastern Tropical North Pacific

    Science.gov (United States)

    Peng, Xuefeng; Fuchsman, Clara A.; Jayakumar, Amal; Oleynik, Sergey; Martens-Habbena, Willm; Devol, Allan H.; Ward, Bess B.

    2015-12-01

    Nitrification plays a key role in the marine nitrogen (N) cycle, including in oceanic oxygen minimum zones (OMZs), which are hot spots for denitrification and anaerobic ammonia oxidation (anammox). Recent evidence suggests that nitrification links the source (remineralized organic matter) and sink (denitrification and anammox) of fixed N directly in the steep oxycline in the OMZs. We performed shipboard incubations with 15N tracers to characterize the depth distribution of nitrification in the Eastern Tropical North Pacific (ETNP). Additional experiments were conducted to investigate photoinhibition. Allylthiourea (ATU) was used to distinguish the contribution of archaeal and bacterial ammonia oxidation. The abundance of archaeal and β-proteobacterial ammonia monooxygenase gene subunit A (amoA) was determined by quantitative polymerase chain reaction. The rates of ammonia and nitrite oxidation showed distinct subsurface maxima, with the latter slightly deeper than the former. The ammonia oxidation maximum coincided with the primary nitrite concentration maximum, archaeal amoA gene maximum, and the subsurface nitrous oxide maximum. Negligible rates of ammonia oxidation were found at anoxic depths, where high rates of nitrite oxidation were measured. Archaeal amoA gene abundance was generally 1 to 2 orders of magnitude higher than bacterial amoA gene abundance, and inhibition of ammonia-oxidizing bacteria with 10 μM ATU did not affect ammonia oxidation rates, indicating the dominance of archaea in ammonia oxidation. These results depict highly dynamic activities of ammonia and nitrite oxidation in the oxycline of the ETNP OMZ.

  18. 76 FR 66274 - North Pacific Fishery Management Council (NPFMC); Public Meetings

    Science.gov (United States)

    2011-10-26

    ... Fishery Management Council's (Council) Gulf of Alaska (GOA) and Bering Sea/Aleutian Islands (BS/AI... (GOA Plan Team) and Traynor Room (BS/AI Plan Team), Seattle, WA. Council address: North Pacific...

  19. Historical Eastern North Pacific Tropical Cyclone Tracks, 1949-2004 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This Historical Eastern North Pacific Tropical Cyclone Tracks file contains the six-hourly (0000, 0600, 1200, 1800 UTC) center locations and intensities for all...

  20. AFSC/NMML: North Pacific Right Whale Photo-ID Catalog

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The eastern population of the North Pacific right whale (Eubalaena japonica) is the most endangered stock of whales in the world, with recent abundance estimates...

  1. AFSC/NMML: North Pacific Right Whale Vessel Surveys in the Southeastern Bering Sea, 2007 - 2011

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The North Pacific right whale (NPRW) was heavily hunted between the 17th and the 20th centuries. Protection was supposedly afforded by international treaties in the...

  2. Climate Prediction Center (CPC) Monthly Pacific North American Teleconnection Pattern Index

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Monthly tabulated index of the Pacific/ North American teleconnection pattern. The data spans the period 1950 to present. The index is derived from a rotated...

  3. Eelgrass (Zostera marina) Microsatellite DNA Data; Pacific Coast of North America, 2000-2009

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set contains genetic information collected from eelgrass (Zostera marina) populations along the Pacific coast of North America from Alaska to Baha...

  4. 78 FR 34347 - Endangered and Threatened Species; Recovery Plan for the North Pacific Right Whale

    Science.gov (United States)

    2013-06-07

    ... Plan for the North Pacific Right Whale AGENCY: National Marine Fisheries Service, National Oceanic and... Pacific right whale (Eubalaena japonica). ADDRESSES: Electronic copies of the Final Recovery Plan are... recovery. The Northern right whale (Eubalaena glacialis) has been listed as ``endangered'' under...

  5. Estimating historical eastern North Pacific blue whale catches using spatial calling patterns.

    Directory of Open Access Journals (Sweden)

    Cole C Monnahan

    Full Text Available Blue whales (Balaenoptera musculus were exploited extensively around the world and remain endangered. In the North Pacific their population structure is unclear and current status unknown, with the exception of a well-studied eastern North Pacific (ENP population. Despite existing abundance estimates for the ENP population, it is difficult to estimate pre-exploitation abundance levels and gauge their recovery because historical catches of the ENP population are difficult to separate from catches of other populations in the North Pacific. We collated previously unreported Soviet catches and combined these with known catches to form the most current estimates of North Pacific blue whale catches. We split these conflated catches using recorded acoustic calls from throughout the North Pacific, the knowledge that the ENP population produces a different call than blue whales in the western North Pacific (WNP. The catches were split by estimating spatiotemporal occurrence of blue whales with generalized additive models fitted to acoustic call patterns, which predict the probability a catch belonged to the ENP population based on the proportion of calls of each population recorded by latitude, longitude, and month. When applied to the conflated historical catches, which totaled 9,773, we estimate that ENP blue whale catches totaled 3,411 (95% range 2,593 to 4,114 from 1905-1971, and amounted to 35% (95% range 27% to 42% of all catches in the North Pacific. Thus most catches in the North Pacific were for WNP blue whales, totaling 6,362 (95% range 5,659 to 7,180. The uncertainty in the acoustic data influence the results substantially more than uncertainty in catch locations and dates, but the results are fairly insensitive to the ecological assumptions made in the analysis. The results of this study provide information for future studies investigating the recovery of these populations and the impact of continuing and future sources of anthropogenic

  6. Estimating historical eastern North Pacific blue whale catches using spatial calling patterns.

    Science.gov (United States)

    Monnahan, Cole C; Branch, Trevor A; Stafford, Kathleen M; Ivashchenko, Yulia V; Oleson, Erin M

    2014-01-01

    Blue whales (Balaenoptera musculus) were exploited extensively around the world and remain endangered. In the North Pacific their population structure is unclear and current status unknown, with the exception of a well-studied eastern North Pacific (ENP) population. Despite existing abundance estimates for the ENP population, it is difficult to estimate pre-exploitation abundance levels and gauge their recovery because historical catches of the ENP population are difficult to separate from catches of other populations in the North Pacific. We collated previously unreported Soviet catches and combined these with known catches to form the most current estimates of North Pacific blue whale catches. We split these conflated catches using recorded acoustic calls from throughout the North Pacific, the knowledge that the ENP population produces a different call than blue whales in the western North Pacific (WNP). The catches were split by estimating spatiotemporal occurrence of blue whales with generalized additive models fitted to acoustic call patterns, which predict the probability a catch belonged to the ENP population based on the proportion of calls of each population recorded by latitude, longitude, and month. When applied to the conflated historical catches, which totaled 9,773, we estimate that ENP blue whale catches totaled 3,411 (95% range 2,593 to 4,114) from 1905-1971, and amounted to 35% (95% range 27% to 42%) of all catches in the North Pacific. Thus most catches in the North Pacific were for WNP blue whales, totaling 6,362 (95% range 5,659 to 7,180). The uncertainty in the acoustic data influence the results substantially more than uncertainty in catch locations and dates, but the results are fairly insensitive to the ecological assumptions made in the analysis. The results of this study provide information for future studies investigating the recovery of these populations and the impact of continuing and future sources of anthropogenic mortality. PMID

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-08-15

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

  8. The last interglacial period on the Pacific Coast of North America: Timing and paleoclimate

    Science.gov (United States)

    Muhs, D.R.; Simmons, K.R.; Kennedy, G.L.; Rockwell, T.K.

    2002-01-01

    New, high-precision U-series ages of solitary corals (Balanophyllia elegans) coupled with molluscan faunal data from marine terraces on the Pacific Coast of North America yield information about the timing and warmth of the last interglacial sea-level highstand. Balanophyllia elegans takes up U in isotopic equilibrium with seawater during growth and shortly after death. Corals from the second terrace on San Clemente Island (offshore southern California), the third terrace on Punta Banda (on the Pacific Coast of northern Baja California), and the Discovery Point Formation on Isla de Guadalupe (in the Pacific Ocean offshore Baja California) date to the peak of the last interglacial period and have U-series ages ranging from ca. 123 to 114 ka. The first terrace on Punta Banda has corals with ages ranging from ca. 83 to 80 ka, which corresponds to a sea-level highstand formed in the late last interglacial period. U-series analyses of corals from the Cayucos terrace (central California) and the Nestor terrace at Point Loma (southern California) show that these fossils have evidence of open-system history, similar to what has been reported by other workers for the same localities. Nevertheless, a model of continuous, secondary U and Th uptake shows that two ages of corals are likely present at these localities, representing the ca. 105 and ca. 120 ka sea-level highstands reported elsewhere. U-series ages of last interglacial corals from the Pacific Coast overlap with, but are on average younger than the ages of corals from Barbados, the Bahamas, and Hawaii. This age difference is explained by the nature of the geomorphic response to sea-level change: fringing or barrier reefs on low-latitude coastlines have an accretionary growth style that keeps pace with rising sea level, whether on a tectonically rising or stable coastline. In contrast, midlatitude, high-energy coastlines are sites of platform cutting during the early part of a sea-level high stand and terrace

  9. 76 FR 71321 - North Pacific Fishery Management Council; Public Meetings

    Science.gov (United States)

    2011-11-17

    ... Operations and Procedures (SOPPs) review/approval and update on workshop with International Pacific Halibut... Service Report; Protected Species Report (including Steller Sea Lion (SSL) Center of Independent...

  10. 76 FR 2084 - North Pacific Fishery Management Council; Public Meetings

    Science.gov (United States)

    2011-01-12

    ... discussion paper and TRAWLEX report). Alaska Department of Fish & Game Report. International Pacific Halibut... Species Report (including update on Steller Sea Lion (SSL); Endangered Species Act (ESA) listed...

  11. Accumulation reconstruction and water isotope analysis for 1735–1997 of an ice core from the Ushkovsky volcano, Kamchatka, and their relationships to North Pacific climate records

    Directory of Open Access Journals (Sweden)

    T. Sato

    2013-04-01

    Full Text Available To investigate past climate change in the Northwest Pacific region, an ice core was retrieved in June 1998 from the Gorshkov crater glacier at the top of the Ushkovsky volcano, in central Kamchatka. Hydrogen isotope (δD analysis and past accumulation reconstructions were conducted to a depth of 140.7 m, dated to 1735. Two accumulation reconstruction methods were applied with the Salamatin and the Elmer/Ice ice flow models. Reconstructed accumulation rates and δD were significantly correlated with North Pacific surface temperature. This, and a significant correlation of δD with the North Pacific Gyre Oscillation (NPGO index implies that NPGO data is contained in this record. Wavelet analysis shows that the ice core records have significant multi-decadal power spectra up to the late 19th century. The multi-decadal periods of reconstructed accumulation rates change at around 1850 in the same way as do Northeast Pacific ice core and tree ring records. The loss of multi-decadal scale power spectra of δD and the 6‰ increase in its average value occurred around 1880. Thus the core record confirms that the periodicity of precipitation for the entire North Pacific changed between the end of the Little Ice Age through the present due to changes in conditions in the North Pacific Ocean.

  12. Interannual Variation of Multiple Tropical Cyclone Events in the Western North Pacific

    Institute of Scientific and Technical Information of China (English)

    GAO Jianyun; Tim LI

    2012-01-01

    The interannual variability of occurrence of multiple tropical cyclone (MTC) events during June-October in the western North Pacific (WNP) was examined for the period 1979-2006.The number of the MTC events ranged from 2 to 9 per year,exhibiting a remarkable year-to-year variation.Seven active and seven inactive MTC years were identified.Compared to the inactive years,tropical cyclone genesis locations extended farther to the east and in the meridional direction during the active MTC years.A composite analysis shows that inactive MTC years were often associated with the El Ni(n)o decaying phase,as warm SST anomalies in the equatorial eastern-central Pacific in the preceding winter transitioned into cold sea surface temperature (SST) anomalies in the concurrent summer.Associated with the SST evolution were suppressed low-level cyclonic vorticity and weakened convection in the WNP monsoon region.In addition to the mean flow difference,significant differences between active and inactive MTC years were also found in the strength of the atmospheric intraseasonal oscillation (ISO).Compared with inactive MTC years,ISO activity was much stronger along the equator and in the WNP region during active MTC years.Both westward- and northward-propagating ISO spectrums strengthened during active MTC years compared to inactive years.The combined mean state and ISO activity changes may set up a favorable environment for the generation of MTC events.

  13. Four years' observations of terrestrial lipid class compounds in marine aerosols from the western North Pacific

    Science.gov (United States)

    Kawamura, K.; Ishimura, Y.; Yamazaki, K.

    2003-03-01

    In order to understand the long-range atmospheric transport of terrestrial organic matter over the open ocean, marine aerosol samples were collected on a biweekly basis from 1990 to 1993 in a remote island, Chichi-Jima, in the western North Pacific. The samples were analyzed for lipid class compounds using a capillary gas chromatography (GC) and GC/mass spectrometry (GC/MS). A homologous series of n-alkanes (C20-C40), alcohols (C13-C34), fatty acids (C9-C34) and α,ω-dicarboxylic acids (C7-C28) were detected in the aerosol samples. Distributions of n-alkanes (0.17-14 ngm-3, average 1.7 ngm-3) are characterized by a strong odd-carbon number predominance (CPI ratios, average 4.5) with a maximum at C29 or C31, indicating that n-alkanes are mainly derived from terrestrial higher plant waxes. Fatty alcohols (0.19-23 ngm-3, average 2.0 ngm-3) show an even-carbon number predominance with a maximum generally at C26 or C28, again indicating a contribution from terrestrial higher plants. On the other hand, fatty acids (2.5-38 ngm-3, average 14 ngm-3) show a bimodal distribution with two maxima at C16 and C24 or C28. Lower molecular weight fatty acids (generally fatty acids (C21-C34) derived from terrestrial higher plants, together with C25-C35 alkanes, C20-C34 alcohols and C20-C28 dicarboxylic acids, generally showed higher concentrations in winter to spring seasons. This seasonal trend is most likely interpreted as atmospheric transport of terrestrial organic matter from Asian continent in winter/spring, when westerly winds dominate over the western North Pacific. Backward trajectory analyses supported the long-range atmospheric transport of higher plant- and soil-derived organic matter from the Asian continent over the Pacific Ocean. This study also suggested that the atmospheric transport is the main pathway for the terrestrial lipid compounds that are abundantly present in the deep-sea sediments in the Central Pacific.

  14. Cob biomass supply for bioenergy in the north central USA

    Science.gov (United States)

    Corn (Zea mays L) cobs are being evaluated as a potential bioenergy feedstock for combined heat and power generation (CHP) and conversion into a liquid biofuel. The objective of this study was to determine corn cob availability in north central U.S. (Minnesota, North Dakota, and South Dakota) using...

  15. Climatic evolution of the central equatorial Pacific since the Last Glacial Maximum

    Science.gov (United States)

    Seo, Inah; Lee, Yuri; Lee, Yong Il; Yoo, Chan Min; Hyeong, Kiseong

    2016-08-01

    This paper investigates paleoceanographic changes at a central equatorial Pacific site (6°40'N, 177°28'W) since the last glacial maximum using planktic foraminifera assemblages, together with the oxygen isotope (δ18O) and Mg/Ca compositions of three species (Globigerinoides sacculifer, Pulleniatina obliquiloculata, and Globorotalia tumida) that dwell in the mixed layer, upper thermocline, and lower thermocline, respectively. While the Mg/Ca-derived temperatures of the mixed layer and lower thermocline varied within a narrow range from 18 ka onward, the upper thermocline temperature increased by as much as 3°C during the last deglaciation (18-12 ka) with a simultaneous decrease of δ18O. These changes are best explained by an enhanced mixing of the upper ocean and a reduced habitat depth separation between P. obliquiloculata and G. sacculifer during the 18-12 ka interval. The planktic foraminifera assemblage during the same period resembles modern composition at subtropical central Pacific sites that are strongly influenced by the northeasterly Trades and North Equatorial Current (NEC). We suggest that the study site, presently under the control of the Intertropical Convergence Zone (ITCZ)-North Equatorial Countercurrent, had been influenced by the northeasterly Trades and NEC during the 18-12 ka interval. This interpretation is consistent with previous documentation of a more southerly location of the ITCZ during two Northern Hemisphere cooling events; the Heinrich Stadial 1 and the Younger Dryas, and implies that the mean annual position of the ITCZ was located south of the study site, by at least 2° of latitude.

  16. CRED Simrad em300 multibeam backscatter data from shelf and slope environments at Howland Island, Pacific Remote Island Areas, Central Pacific in netCDF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Howland Island, Pacific Remote Island Areas, Central Pacific. These data provide coverage between...

  17. CRED Simrad em300 multibeam backscatter data of Baker Island, Pacific Remote Island Areas, Central Pacific in GeoTIFF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of the shelf and slope environments of Baker Island, Pacific Island Areas, Central Pacific. These...

  18. CRED Simrad em300 multibeam backscatter data of Johnston Atoll, Pacific Remote Island Areas, Central Pacific in GeoTIFF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of the shelf and slope environments of Johnston Island, Pacific Island Areas, Central Pacific. These...

  19. CRED Simrad em300 multibeam backscatter data of Jarvis Island, Pacific Remote Island Areas, Central Pacific in GeoTIFF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of the shelf and slope environments of Jarvis Atoll, Pacific Island Areas, Central Pacific. These...

  20. Climate impacts on the structures of the North Pacific air-sea CO2 flux variability

    Directory of Open Access Journals (Sweden)

    Y. Nojiri

    2011-05-01

    Full Text Available Some dominant spatial and temporal structures of the North Pacific air-sea CO2 fluxes in response to the Pacific Decadal Oscillation (PDO are identified in four data products from four independent sources: an assimilated CO2 flux product, two forward model solutions, and a gridded pCO2 dataset constructed with a neural network approach. The interannual variability of CO2 flux is found to be an order of magnitude weaker compared to the seasonal cycle of CO2 flux in the North Pacific. A statistical approach is employed to quantify the signal-to-noise ratio in the reconstructed dataset to delineate the representativity errors. The dominant variability with a signal-to-noise ratio above one is identified and its correlations with PDO are examined. A tentative four-box structure in the North Pacific air-sea CO2 flux variability linked to PDO emerges in which two positively correlated boxes are oriented in the northwest and southeast directions and contrarily, the negatively correlated boxes are oriented in the northeast and southwest directions. This pattern is verified with the CO2 and pCO2 from four products and its relations to the interannual El Niño-Southern Oscillation (ENSO and lower-frequency PDO are separately identified. A combined EOF analysis between air-sea CO2 flux and key variables representing ocean-atmosphere interactions is carried out to elicit robust oscillations in the North Pacific CO2 flux in response to the PDO. The proposed spatial and temporal structures of the North Pacific CO2 fluxes are insightful since they separate the secular trends of the surface ocean carbon from the interannual variability. The regional characterization of the North Pacific in terms of PDO and CO2 flux variability is also instructive for determining the homogeneous oceanic domains for the Regional Carbon Cycle and Assessment Processes (RECCAP.

  1. 77 FR 67633 - North Pacific Fishery Management Council; Public Meetings

    Science.gov (United States)

    2012-11-13

    ... (including Aleutian Island Risk Assessment) United State Fish & Wildlife (USFWL) Report International Pacific... restrictions; discussion paper on retention of 4A halibut in sablefish pots. 5. Steller Sea Lion...

  2. Relationship between the Asian-Pacific oscillation and the tropical cyclone frequency in the western North Pacific

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The relationship between the Asian-Pacific oscillation (APO) and the tropical cyclone frequency over the western North Pacific (WNP) in summer is preliminarily investigated through an analysis of ob- served data. The result has shown clearly that APO is significantly and positively correlated to the tropical cyclone frequency in the WNP. If APO is above (below) the normal in summer, more (less) tropical cyclones will tend to appear in the WNP. The present study also addresses the large-scale at- mospheric general circulation changes underlying the linkage between APO and the WNP tropical cy- clone frequency. It follows that a positive phase of summer APO is concurrent with weakened as well as northward and eastward located western Pacific subtropical high (WPSH), low-level convergence and high-level divergence, and reduced vertical zonal wind shear in the WNP, providing favorable envi- ronment for the tropical cyclone genesis, and thus more tropical cyclones will come into being, and vice versa.

  3. Relationship between the Asian-Pacific oscillation and the tropical cyclone frequency in the western North Pacific

    Institute of Scientific and Technical Information of China (English)

    ZHOU BoTao; CUI Xuan; ZHAO Ping

    2008-01-01

    The relationship between the Asian-Pacific oscillation (APO) and the tropical cyclone frequency over the western North Pacific (WNP) in summer is preliminarily investigated through an analysis of observed data. The result has shown clearly that APO is significantly and positively correlated to the tropical cyclone frequency in the WNP. If APO is above (below) the normal in summer, more (less) tropical cyclones will tend to appear in the WNP. The present study also addresses the large-scale atmospheric general circulation changes underlying the linkage between APO and the WNP tropical cyclone frequency. It follows that a positive phase of summer APO is concurrent with weakened as well as northward and eastward located western Pacific subtropical high (WPSH), low-level convergence and high-level divergence, and reduced vertical zonal wind shear in the WNP, providing favorable environment for the tropical cyclone genesis, and thus more tropical cyclones will come into being, and vice versa.

  4. Age Dependent 3-D Magnetic Modeling of the North Pacific and North Atlantic Oceanic Crust at Intermediate Wavelengths

    Science.gov (United States)

    Yanez, Gonzalo A.; LaBrecque, John L.

    1996-01-01

    Three-dimensional magnetic modeling of the North Atlantic and Northeast pacific is performed at intermediate wavelengths using three models for the acquisition of a natural remanent magnetization. It is shown that a remanent magnetization which is dependent on the rustal age is the dominant source for the intermediate wavelength pattern in both basins.

  5. CCSM3 simulation of pacific multi-decadal climate variability: the role of subpolar North Pacific Ocean

    International Nuclear Information System (INIS)

    Previous analyses of the CCSM3 standard integration have revealed pronounced multidecadal variability in the Pacific climate system. The purpose of the present work is to investigate the physical mechanism underlying the Pacific multidecadal variability (PMV) using specifically designed sensitivity experiments. A novel mechanism is advanced, characterized by a crucial role of the subpolar North Pacific Ocean. The multidecadal signal in ocean temperature and salinity fields is found to originate from the subsurface of the subpolar North Pacific, as result of the wave adjustment to the preceding basin-scale wind curl forcing. The multidecadal signal then ascends to the surface and is amplified through local temperature/salinity convective feedback. Along the southward Oyashio current, the anomaly travels to the Kuroshio Extension (KOE) region and is further intensified through a similar convective feedback in addition to the wind-evaporation-sea surface temperature feedback. The temperature anomaly in the KOE is able to feed back to the large-scale atmospheric circulation, inducing wind curl anomaly over the subpolar region, which in turn generates anomalous oceanic circulation and causes temperature/salinty variability in the subpolar subsurface. Thereby, a closed loop of PMV is established, in the form of a subpolar delayed oscillator

  6. Evaluating the impacts of eastern North Pacific tropical cyclones on North America utilizing remotely-sensed and reanalysis data

    Science.gov (United States)

    Wood, Kimberly M.

    The eastern North Pacific Ocean has the highest density of tropical cyclone genesis events of any tropical basin in the world, and many of these systems form near land before moving westward. However, despite the level of tropical cyclone activity in this basin, and the proximity of the main genesis region to land, tropical cyclone behavior in the eastern North Pacific has been relatively unexplored. When synoptic conditions are favorable, moisture from northward-moving tropical cyclones can be advected into northern Mexico and the southwestern United States, often leading to the development of summertime thunderstorms during the North American monsoon season. An interaction with a mid-latitude trough produces the most rainfall, and the spatial variability of precipitation is greatly affected by the complex topography of the region. Moisture can be advected from a tropical cyclone around the subtropical ridge in place for much of the eastern North Pacific hurricane season and contribute to precipitation. This ridge, when it extends westward over the Pacific Ocean, can also prevent tropical cyclone moisture from impacting the southwestern United States. Northward-moving tropical cyclones often enter an environment with decreasing sea surface temperatures, increasing vertical wind shear, and meridional air temperature and moisture gradients. These key ingredients for extratropical transition are generally present in the eastern North Pacific, but the subtropical ridge prevents many named systems from moving northward, and only 9% of eastern North Pacific tropical cyclones from 1970 to 2011 complete ET according to cyclone phase space. However, over half of the systems that do not complete ET dissipate as cold core cyclones, a structural change that has yet to be explored in other tropical basins. It is difficult to estimate tropical cyclone intensity in a vast ocean area with few direct measurements available. The deviation angle variance technique, an objective

  7. Delayed Impacts of the E1 Nino Episodes in the Central Pacific on the Summertime Climate Anomalies of Eastern China in 2003 and 2007

    Institute of Scientific and Technical Information of China (English)

    BAO Ming; HAN Rongqing

    2009-01-01

    In the summers of 2003 and 2007, eastern China suffered similar climate disasters with severe flooding in the Huaihe River valley and heat waves in the southern Yangtze River delta and South China. Using SST data and outgoing longwave radiation (OLR) data from NOAA along with reanalysis data from NCEP/NCAR, the 2002/03 and 2006/07 El Ni(n)o episodes in the central Pacific and their delayed impacts on the following early summertime climate anomalies of eastern China were analyzed. The possible physical progresses behaved as follows: Both of the moderate E1 Ni(n)o episodes matured in the central equatorial Pacific during the early winter. The zonal wind anomalies near the sea surface of the west-central equatorial Pacific excited equatorial Kelvin waves propagating eastward and affected the evolution of the E1 Ni(n)o episodes. From spring to early summer, the concurring anomalous easterly winds in the central equatorial Pacific and the end of upwelling Kelvin waves propagating eastward in the western equatorial Pacific, favored the equatorial warm water both of the SST and the subsurface temperature in the western Pacific. These conditions favored the warm state of the western equatorial Pacific in the early summer for both cases of 2003 and 2007. Due to the active convection in the western equatorial Pacific in the early summer and the weak warm SST anomalies in the tropical western Pacific from spring to early summer, the convective activities in the western Pacific warm pool showed the pattern in which the anomalous strong convection only appeared over the southern regions of the tropical western Pacific warm pool, which effects the meridional shift of the western Pacific subtropical high in the summer. The physical progress of the delayed impacts of the E1 Nifio episodes in the central equatorial Pacific and their decaying evolution on the climate anomalies in eastern China were interpreted through the key role of special pattern for the heat convection in the

  8. Dependency of the North Pacific winter storm tracks on the zonal distribution of MJO convection

    Science.gov (United States)

    Lee, Yun-Young; Lim, Gyu-Ho

    2012-07-01

    We investigate the effects of the tropical Madden Julian Oscillation (MJO) convection on the zonal location and intensity of storm activity during the boreal cool season (Nov. 1 to Feb. 28, 120 days) over the Pacific Ocean. As tropical convection shifts eastward from the eastern Indian Ocean to the western North Pacific, MJO-induced local Hadley circulation leads to an eastward displacement of extratropical Rossby Wave Source (RWS). Consequently, this influence leads to an eastward shift of the peak area of the storm track. The storm track is strongest with the MJO convection over the eastern Indian Ocean (phase 3), and it experiences the suppression when MJO convection is located over the Maritime continents (phase 4), and it increases again when the MJO propagates to the western Pacific (phase 5), after which it weakens again (phase 6). The intensity of the storm track, particularly over the western North Pacific (120°E-180°), is determined by the integrated effects of three factors: the midlatitude convective forcing (MCF), the jet stream, and RWS. These factors are associated with the locations of MJO convections. It is estimated that MJO-induced suppression accounts for only 2.5% of the total observed midwinter suppression (MWS). However, the pattern generated by the MJO is remarkably similar to the observed meridional displacement of North Pacific storm track associated with sub-seasonal variation. We conclude that the spatial distribution of MJO affects the variation of the Pacific storm track, but is not a cause of the MWS.

  9. Rayleigh phase velocities in the upper mantle of the Pacific-North American plate boundary in southern California

    Science.gov (United States)

    Escobar, L.; Weeraratne, D. S.; Kohler, M. D.

    2013-05-01

    The Pacific-North America plate boundary, located in Southern California, presents an opportunity to study a unique tectonic process that has been shaping the plate tectonic setting of the western North American and Mexican Pacific margin since the Miocene. This is one of the few locations where the interaction between a migrating oceanic spreading center and a subduction zone can be studied. The rapid subduction of the Farallon plate outpaced the spreading rate of the East Pacific Rise rift system causing it to be subducted beneath southern California and northern Mexico 30 Ma years ago. The details of microplate capture, reorganization, and lithospheric deformation on both the Pacific and North American side of this boundary is not well understood, but may have important implications for fault activity, stresses, and earthquake hazard analysis both onshore and offshore. We use Rayleigh waves recorded by an array of 34 ocean bottom seismometers deployed offshore southern California for a 12 month duration from August 2010 to 2011. Our array recorded teleseismic earthquakes at distances ranging from 30° to 120° with good signal-to-noise ratios for magnitudes Mw ≥ 5.9. The events exhibit good azimuthal distribution and enable us to solve simultaneously for Rayleigh wave phase velocities and azimuthal anisotropy. Fewer events occur at NE back-azimuths due to the lack of seismicity in central North America. We consider seismic periods between 18 - 90 seconds. The inversion technique considers non-great circle path propagation by representing the arriving wave field as two interfering plane waves. This takes advantage of statistical averaging of a large number of paths that travel offshore southern California and northern Mexico allowing for improved resolution and parameterization of lateral seismic velocity variations at lithospheric and sublithospheric depths. We present phase velocity results for periods sampling mantle structure down to 150 km depth along the

  10. Implications of new economic policy instruments for tuna management in the Western and Central Pacific

    NARCIS (Netherlands)

    Yeeting, A.D.; Bush, S.R.; Ram-Bidesi, V.; Bailey, M.L.

    2015-01-01

    Tuna management in the Western and Central Pacific is complicated by the conflicting interests of countries and agents exploiting tuna resources in the region. Historically, regulatory attempts by Pacific Island Countries to control fishing effort within their Exclusive Economic Zones (EEZs) have me

  11. North Pacific Mesoscale Coupled Air-Ocean Simulations Compared with Observations

    Energy Technology Data Exchange (ETDEWEB)

    Cerovecki, Ivana [Univ. of California, San Diego, CA (United States). Scripps Inst. of Oceanography; McClean, Julie [Univ. of California, San Diego, CA (United States). Scripps Inst. of Oceanography; Koracin, Darko [Desert Research Inst. (DRI), Reno, NV (United States). Division of Atmospheric Sciences

    2014-11-14

    The overall objective of this study was to improve the representation of regional ocean circulation in the North Pacific by using high resolution atmospheric forcing that accurately represents mesoscale processes in ocean-atmosphere regional (North Pacific) model configuration. The goal was to assess the importance of accurate representation of mesoscale processes in the atmosphere and the ocean on large scale circulation. This is an important question, as mesoscale processes in the atmosphere which are resolved by the high resolution mesoscale atmospheric models such as Weather Research and Forecasting (WRF), are absent in commonly used atmospheric forcing such as CORE forcing, employed in e.g. the Community Climate System Model (CCSM).

  12. Intrusion of Fukushima-derived radiocaesium into subsurface water due to formation of mode waters in the North Pacific

    Science.gov (United States)

    Kaeriyama, Hideki; Shimizu, Yugo; Setou, Takashi; Kumamoto, Yuichiro; Okazaki, Makoto; Ambe, Daisuke; Ono, Tsuneo

    2016-02-01

    The Fukushima Dai-ichi Nuclear Power Plant accident in March 2011 released radiocaesium (137Cs and 134Cs) into the North Pacific Ocean. Meridional transects of the vertical distribution of radiocaesium in seawater were measured along 147 °E and 155 °E in October-November 2012, 19 months after the accident. These measurements revealed subsurface peaks in radiocaesium concentrations at locations corresponding to two mode waters, Subtropical Mode Water and Central Mode Water. Mode water is a layer of almost vertically homogeneous water found over a large geographical area. Here we show that repeated formation of mode water during the two winter seasons after the Fukushima accident and subsequent outcropping into surface water transported radiocaesium downward and southward to subtropical regions of the North Pacific. The total amount of Fukushima-derived 134Cs within Subtropical Mode Water, decay-corrected to April 2011, was estimated to be 4.2 ± 1.1 PBq in October-November 2012. This amount of 134Cs corresponds to 22-28% of the total amount of 134Cs released to the Pacific Ocean.

  13. Helium isotopes in ferromanganese crusts from the central Pacific Ocean

    Science.gov (United States)

    Basu, S.; Stuart, F.M.; Klemm, V.; Korschinek, G.; Knie, K.; Hein, J.R.

    2006-01-01

    Helium isotopes have been measured in samples of two ferromanganese crusts (VA13/2 and CD29-2) from the central Pacific Ocean. With the exception of the deepest part of crust CD29-2 the data can be explained by a mixture of implanted solar- and galactic cosmic ray-produced (GCR) He, in extraterrestrial grains, and radiogenic He in wind-borne continental dust grains. 4He concentrations are invariant and require retention of less than 12% of the in situ He produced since crust formation. Loss has occurred by recoil and diffusion. High 4He in CD29-2 samples older than 42 Ma are correlated with phosphatization and can be explained by retention of up to 12% of the in situ-produced 4He. 3He/4He of VA13/2 samples varies from 18.5 to 1852 Ra due almost entirely to variation in the extraterrestrial He contribution. The highest 3He/4He is comparable to the highest values measured in interplanetary dust particles (IDPs) and micrometeorites (MMs). Helium concentrations are orders of magnitude lower than in oceanic sediments reflecting the low trapping efficiency for in-falling terrestrial and extraterrestrial grains of Fe-Mn crusts. The extraterrestrial 3He concentration of the crusts rules out whole, undegassed 4–40 μm diameter IDPs as the host. Instead it requires that the extraterrestrial He inventory is carried by numerous particles with significantly lower He concentrations, and occasional high concentration GCR-He-bearing particles.

  14. CRED 10 m Gridded multibeam bathymetry of Wake Island, West Central Pacific

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry shelf, bank and slope environments of Wake Island, West Central Pacific, under joint management of the United States Dept. of Interior and Air...

  15. CRED 60 m Gridded multibeam bathymetry of Wake Island, West Central Pacific

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry shelf, bank and slope environments of Wake Island, West Central Pacific, under joint management of the United States Dept. of Interior and Air...

  16. CRED 1 meter resolution Reson 8101 multibeam backscatter data of Wake Island, West Central Pacific, 2007.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Wake Island, West Central Pacific.These data provide coverage between 0 and 200m meters. The...

  17. Updated precipitation reconstruction (AD 1482-2012) for Huashan, north-central China

    Science.gov (United States)

    Chen, Feng; Zhang, Ruibo; Wang, Huiqin; Qin, Li; Yuan, Yujiang

    2016-02-01

    We developed a tree-ring width chronology from pine trees ( Pinus tabulaeformis and Pinus armandii) stand near the peaks of Huashan, Shaanxi, north-central China. Growth-climate response analyses showed that the radial growth of pine trees is mainly influenced by April-June precipitation. A model to reconstruct precipitation based on tree widths was constructed, accounting for 55 % of the instrumental variance during the period 1953-2012. Spatial correlation analyses between the reconstruction and observed gridded precipitation data shows that the seasonal precipitation reconstruction captures regional climatic variations over north China. Compared with the historical archives and other tree-ring records in north China, many large-scale drought events, linked to the El Niño-Southern Oscillation (ENSO), were found. Many of these events have had profound impacts on the people of north China over the past several centuries. Composite maps of sea surface temperatures and 500 hPa geopotential heights for selected extremely dry and wet years in Huashan show characteristics similar to those related to the ENSO patterns, particularly with regard to ocean and atmospheric conditions in the equatorial and north Pacific. Our 531-year precipitation reconstruction for Huashan provides a long-term perspective on current and 20th century wet and dry events in north China, and is useful to guide expectations of future variability, and helps us to address climate change.

  18. 75 FR 70903 - Eastern North Pacific Gray Whale; Notice of Extension of Public Comment Period on Marine Mammal...

    Science.gov (United States)

    2010-11-19

    ... on the petition (75 FR 68756). That Federal Register notice began NMFS' 15-day public comment period... National Oceanic and Atmospheric Administration RIN 0648-XA018 Eastern North Pacific Gray Whale; Notice of... petition to designate the Eastern North Pacific population of gray whales (Eschrichtius robustus) as...

  19. Uncertainty in future projections of the North Pacific subtropical high and its implication for California winter precipitation change

    Science.gov (United States)

    Choi, Jung; Lu, Jian; Son, Seok-Woo; Frierson, Dargan M. W.; Yoon, Jin-Ho

    2016-01-01

    This study examines future projections of sea level pressure change in the North Pacific and its impact on winter precipitation changes in California. The multimodel analysis, based on the Coupled Model Intercomparison Project phase 5 models under the Representative Concentration Pathway 8.5 scenario, shows a robust sea level pressure change in the late 21st century over the western North Pacific in which both the Aleutian Low and the North Pacific subtropical high (NPSH) shift poleward in concert with a widening of the Hadley cell. This change is partly explained by a systematic increase of static stability in the subtropics. Despite its robustness, the projected NPSH changes over the eastern North Pacific exhibit a substantial intermodel spread, contributing as a cause for uncertain projections of precipitation changes in California. This intermodel spread in the eastern North Pacific is associated with a Pacific Decadal Oscillation-like surface temperature change in the western North Pacific and the resulting meridional temperature gradient change. This study points to a major source of uncertainty for the response of winter precipitation to global warming over the West Coast of North America: atmosphere-ocean coupling in the North Pacific.

  20. North Central regional environmental characterization report: executive summary - final

    International Nuclear Information System (INIS)

    This Executive Summary of the final North Central Regional Environmental Characterization Report (RECR) is issued primarily for public information purposes and provides a general overview of the report. The complete RECR presents available regional environmental information pertinent to siting a repository for high-level nuclear waste in crystalline rock in Minnesota, Wisconsin, and the Upper Peninsula of Michigan. For each of the States within the North Central Region, information is provided on the environmental disqualifying factors and the environmental regional screening variables to be used in region-to-area screening

  1. Neutral carbohydrate geochemistry of particulate material in the central equatorial Pacific

    Science.gov (United States)

    Hernes, Peter J.; Hedges, John I.; Peterson, Michael L.; Wakeham, Stuart G.; Lee, Cindy

    Neutral carbohydrate compositions were determined for particulate samples from plankton net tows, shallow floating sediment traps, mid-depth and deep moored sediment traps, and sediment cores collected along a north-south transect in the central equatorial Pacific Ocean during the U.S. JGOFS EqPac program. Total neutral carbohydrate depth profiles and patterns along the transect follow essentially the same trends as bulk and organic carbon (OC) fluxes—attenuating with depth, high near the equator and decreasing poleward. OC-normalized total aldose (TCH 2,O) yields along the transect and with depth do not show any consitent patterns. Relative to a planktonic source, neutral carbohydrate compositions in sediment trap and sediment core samples reflect preferential loss of ribose and storage carbohydrates rich in glucose, and preferential preservation of structural carbohydrates rich in rhamnose, xylose, fucose, and mannose. There is also evidence for an intermediately labile component rich in galactose. It appears that compositional signatures of neutral carbohydrates in sediments are more dependent upon their planktonic source than on any particular diagenetic pathway. Relative to other types of organic matter, neutral carbohydrates are better preserved in calcareous oozes from 12°S to 5°N than in red clays at 9°N based on OC-normalized TCH 2O yields, due to either differing sources or sorption characteristics. Weight per cent glucose generally decreases with increased degradation of organic material in the central equatorial Pacific region. Based on weight per cent glucose, comparisons of samples between Survey I (El Niõn) and Survey II (non-El Niño) indicate that during Survey I, organic material in the epipelagic zone in the northern hemisphere may have undergone more degradation than organic material in the southern hemisphere.

  2. Global Climate network evolves with North Atlantic Oscillation phases: Coupling to Southern Pacific Ocean

    CERN Document Server

    Guez, Oded; Berezin, Yehiel; Wang, Yang; Havlin, Shlomo

    2013-01-01

    We construct a network from climate records of atmospheric temperature at surface level, at different geographical sites in the globe, using reanalysis data from years 1948-2010. We find that the network correlates with the North Atlantic Oscillation (NAO), both locally in the north Atlantic, and through coupling to the southern Pacific Ocean. The existence of tele-connection links between those areas and their stability over time allows us to suggest a possible physical explanation for this phenomenon.

  3. Acoustic detections of singing humpback whales (Megaptera novaeangliae) in the eastern North Pacific during their northbound migration.

    Science.gov (United States)

    Norris, T F; McDonald, M; Barlow, J

    1999-07-01

    Numerous (84) acoustic detections of singing humpback whales were made during a spring (08 March-09 June 1997) research cruise to study sperm whales in the central and eastern North Pacific. Over 15,000 km of track-line was surveyed acoustically using a towed hydrophone array. Additionally, 83 sonobuoys were deployed throughout the study area. Detection rates were greatest in late March, near the Hawaiian Islands, and in early April, northeast of the islands. Only one detection was made after April. Detection rates for sonobuoys were unequal in three equally divided longitudinal regions of the study area. Two high density clusters of detections occurred approximately 1200-2000 km northeast of the Hawaiian Islands and were attributed to a large aggregation of migrating animals. The distribution of these detections corroborates findings of previous studies. It is possible that these animals were maintaining acoustic contact during migration. Two unexpected clusters of singing whales were detected approximately 900 to 1000 km west of central and southern California. The location of these detections may indicate a previously undocumented migration route between an offshore breeding area, such as the Revillagigedo Islands, Mexico, and possible feeding areas in the western North Pacific or Bering Sea. PMID:10420640

  4. Statistical Characteristics of Mesoscale Eddies in the North Pacific Derived from Satellite Altimetry

    Directory of Open Access Journals (Sweden)

    Yu-Hsin Cheng

    2014-06-01

    Full Text Available The sea level anomaly data derived from satellite altimetry are analyzed to investigate statistical characteristics of mesoscale eddies in the North Pacific. Eddies are detected by a free-threshold eddy identification algorithm. The results show that the distributions of size, amplitude, propagation speed, and eddy kinetic energy of eddy follow the Rayleigh distribution. The most active regions of eddies are the Kuroshio Extension region, the Subtropical Counter Current zone, and the Northeastern Tropical Pacific region. By contrast, eddies are seldom observed around the center of the eastern part of the North Pacific Subarctic Gyre. The propagation speed and kinetic energy of cyclonic and anticyclonic eddies are almost the same, but anticyclonic eddies possess greater lifespans, sizes, and amplitudes than those of cyclonic eddies. Most eddies in the North Pacific propagate westward except in the Oyashio region. Around the northeastern tropical Pacific and the California currents, cyclonic and anticyclonic eddies propagate westward with slightly equatorward (197° average azimuth relative to east and poleward (165° deflection, respectively. This implies that the background current may play an important role in formation of the eddy pathway patterns.

  5. Comparative Resilience in Five North Pacific Regional Salmon Fisheries

    OpenAIRE

    Courtland L. Smith; Xanthippe Augerot

    2010-01-01

    Over the past century, regional fisheries for Pacific salmon (Oncorhynchus spp.) have been managed primarily for their provisioning function, not for ecological support and cultural significance. We examine the resilience of the regional salmon fisheries of Japan, the Russian Far East, Alaska, British Columbia, and Washington-Oregon-California (WOC) in terms of their provisioning function. Using the three dimensions of the adaptive cycle—capital, connectedness, and resilience—we i...

  6. Tectonic implications of post-30 Ma Pacific and North American relative plate motions

    Science.gov (United States)

    Bohannon, R.G.; Parsons, T.

    1995-01-01

    The Pacific plate moved northwest relative to North America since 42 Ma. The rapid half rate of Pacific-Farallon spreading allowed the ridge to approach the continent at about 29 Ma. Extinct spreading ridges that occur offshore along 65% of the margin document that fragments of the subducted Farallon slab became captured by the Pacific plate and assumed its motion proper to the actual subduction of the spreading ridge. This plate-capture process can be used to explain much of the post-29 Ma Cordilleran North America extension, strike slip, and the inland jump of oceanic spreading in the Gulf of California. Much of the post-29 Ma continental tectonism is the result of the strong traction imposed on the deep part of the continental crust by the gently inclined slab of subducted oceanic lithosphere as it moved to the northwest relative to the overlying continent. -from Authors

  7. Relationships between the North Pacific Oscillation and the typhoon/hurricane frequencies

    Institute of Scientific and Technical Information of China (English)

    WANG; HuiJun; SUN; JianQi; FAN; Ke

    2007-01-01

    Relationships between the North Pacific Oscillation (NPO) and the typhoon as well as hurricane frequencies are documented. The correlation between NPO index in June-July-August-September and the annual typhoon number in the western North Pacific is 0.37 for the period of 1949―1998. The NPO is correlated with the annual hurricane number in the tropical Atlantic at - 0.28 for the same period. The variability of NPO is found to be concurrent with the changes of the magnitude of vertical zonal wind shear, sea-level pressure patterns, as well as the sea surface temperature, which are physically associated with the typhoons and hurricanes genesis. The NPO associated atmospheric circulation variability is analyzed to explain how NPO is linked with variability of the tropical atmospheric circulation in the western Pacific and the tropical Atlantic, via the atmospheric teleconnection.

  8. Relationship between the Antarctic oscillation in the western North Pacific typhoon frequency

    Institute of Scientific and Technical Information of China (English)

    WANG HuiJun; FAN Ke

    2007-01-01

    Relationship between the Antarctic oscillation (AAO) and the western North Pacific typhoon number (WNPTN) in the interannual variability is examined in this research. The WNPTN is correlated with the AAO in June-July-August-September (JJAS) in 1949-1998 at -0.48 for the detrended time series, statistically significant at 99% level. The tropical atmospheric circulation as well as the sea surface temperature variability over the western Pacific associated with AAO has been analyzed. It follows that a positive phase of JJAS AAO corresponds to the larger magnitude of the vertical zonal wind shear, the anomalous low-lever anti-cyclonic circulation and anomalous high-level cyclonic circulation, and lower sea surface temperature in the major typhoon genesis region in the western North Pacific, thus providing unfavorable environment for the typhoon genesis, and vice versa.

  9. Pollution transport across the Pacific and its impact on North America

    International Nuclear Information System (INIS)

    Full text: We present a study about the transport of pollution across the Pacific and how this long-range transport impacts the atmospheric composition over North America both on a regional and a local scale. Our focus is on spring 2006 when the NASA INTEX-B campaign (Intercontinental Chemical Transport Experiment) took place. The extensive set of aircraft and ground based field observations form the basis for the analysis together with satellite observations from the MOPITT and MODIS instruments and model simulations with the global MOZART-4 model and the regional WRF-Chem model. Model tracers are used to examine the contributions of different regions to pollution levels over the Pacific and to estimate the ozone production from anthropogenic NOx sources in Asia to ozone loadings over the Pacific and North America. We acknowledge the INTEX-B team for providing the measurements. (author)

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

    Science.gov (United States)

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

    2009-04-01

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

  11. Atlas of Nonindigenous Marine and Estuarine Species in the North Pacific

    Science.gov (United States)

    The product consists of a report synthesizing available information on nonindigenous species in the North Pacific. We note that while this product focuses on invasive species, the tools and approaches developed for this research are the precursors on how we will address identifyi...

  12. Two new species of the bee genus Peponapis, with a key to the North and Central American species (Hymenoptera: Apidae: Eucerini)

    OpenAIRE

    Ricardo Ayala; Terry Griswold

    2012-01-01

    Two new species of squash bees, Peponapis pacifica Ayala and Griswold sp. n. and P. parkeri Griswold and Ayala sp. n., are described and illustrated. Peponapis pacifica is oligolectic on flowers of Schizocarpum longisepalum (Cucurbitaceae) endemic to Mexico, where it is found in the tropical dry forest along the Pacific Coast, between Sonora and Chiapas and in the Balsas River basin; and P. parkeri is known only from the Pacific slope of Costa Rica. A key for the North and Central American sp...

  13. CHARACTERISTICS OF FARMLAND LEASING IN THE NORTH CENTRAL UNITED STATES

    OpenAIRE

    Patterson, Brian; Hanson, Steven D.; Robison, Lindon J.

    1998-01-01

    Leasing behavior differs across the North Central United States. Survey data is used to characterize leasing activity in the region. Data is collected on the amount of leased farmland, amount of cash and share leased land, and common output share levels. Factors influencing leasing and arrangements are also identified.

  14. World and experiences of AIDS orphans in north central Namibia

    NARCIS (Netherlands)

    Brug, van der M.

    2007-01-01

    How do young AIDS orphans deal with the loss of their parents and their changed circumstances? This thesis discusses the social environment, experiences and perceptions of fourteen orphans in north central Namibia. The author followed the children for five months from September 2003 until March 2004

  15. Possible relationship between East Asian summer monsoon and western North Pacific tropical cyclone genesis frequency

    Science.gov (United States)

    Choi, Ki-Seon; Cha, Yumi; Kim, Hae-Dong; Kang, Sung-Dae

    2016-04-01

    In the present study, the fact that strong positive correlations have existed between East Asian summer monsoons (EASMs) and western North Pacific tropical cyclone (TC) genesis frequency over the last 37 years was found. To figure out the cause of these correlations, 7 years (positive East Asian summer monsoon index (EASMI) phase) that have the highest values and 7 years (negative EASMI phase) that have the lowest values in the normalized EASM index were selected and the differences in averages between the two phases were analyzed. In the positive EASMI phase, TCs mainly occurred in the northwestern waters of the tropical and subtropical western North Pacific and showed a tendency to move from the far eastern waters of the Philippines, pass the East China Sea, and move northward toward Korea and Japan. On the 500 hPa streamline, whereas anomalous anticyclones developed in the East Asia middle-latitude region, anomalous cyclones developed in the tropical and subtropical western North Pacific. Therefore, in this phase, whereas EASMs were weakened, western North Pacific summer monsoons (WNPSMs) were strengthened so that some more TCs could occur. In addition, in the case of the East China Sea and the southern waters of Japan located between the two anomalous pressure systems, TCs could move some more toward the East Asia middle-latitude region in this phase. According to an analysis of the 850 hPa relative vorticity, negative anomalies were strengthened in the East Asia middle-latitude region while positive anomalies were strengthened in the region south to 25 N. Therefore, in the positive EASMI phase, whereas EASMs were weakened, WNPSMs were strengthened so that some more TCs could occur. According to an analysis of the 850 and 200 hPa horizontal divergence, whereas anomalous downward flows were strengthened in the East Asia middle-latitude region, anomalous upward flows were strengthened in the tropical and subtropical western North Pacific. According to an analysis

  16. Wind energy resource atlas. Volume 2. The North Central Region

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, D.L.; Hadley, D.L.; Elliott, D.L.; Barchet, W.R.; George, R.L.

    1981-02-01

    The North Central atlas assimilates six collections of wind resource data: one for the region and one for each of the five states that compose the North Central region (Iowa, Minnesota, Nebraska, North Dakota, and South Dakota). At the state level, features of the climate, topography and wind resource are discussed in greater detail than is provided in the regional discussion, and that data locations on which the assessment is based are mapped. Variations, over several time scales, in the wind resource at selected stations in each state are shown on graphs of monthly average and international wind speed and power, and hourly average wind speed for each season. Other graphs present speed direction and duration frequencies of the wind at these locations.

  17. A revised estimate of Pacific-North America motion and implications for Western North America plate boundary zone tectonics

    Science.gov (United States)

    Demets, Charles; Gordon, Richard G.; Stein, Seth; Argus, Donald F.

    1987-01-01

    Marine magnetic profiles from the Gulf of Californa are studied in order to revise the estimate of Pacific-North America motion. It is found that since 3 Ma spreading has averaged 48 mm/yr, consistent with a new global plate motion model derived without any data. The present data suggest that strike-slip motion on faults west of the San Andreas is less than previously thought, reducing the San Andreas discrepancy with geodetic, seismological, and other geologic observations.

  18. Hydroxylated and methylsulfonyl polychlorinated biphenyl metabolites in albatrosses from Midway Atoll, North Pacific Ocean

    Energy Technology Data Exchange (ETDEWEB)

    Klasson-Wehler, E.; Bergman, A.; Athanasiadou, M. [Stockholm Univ. (Sweden)] [and others

    1998-08-01

    Concentrations of hydroxylated metabolites of polychlorinated biphenyls (PCBs) (OH-PCBs) and methylsulfonyl metabolites of PCBs (MeSO{sub 2}-PCBs) were determined in plasma and liver of albatrosses collected from the Midway Atoll in the central North Pacific Ocean. The mean total concentrations of OH-PCBs in plasma of Laysan albatrosses (Diomedea immutabilis) and black-footed albatrosses (Diomedea nigripes) were 11.5 and 27.1 ng/g wet weight, respectively. Total concentrations of OH-PCBs were only one- to fivefold less than those of total PCBs. 4-hydroxy-2,2{prime},3,4{prime},5,5{prime},6-heptachlorinated biphenyl and 4-hydroxy-2,2{prime},3,4{prime},5,5{prime}-hexachlorinated biphenyl were the predominant polychlorinated biphenylols, constituting 70 to 90% of the total OH-PCBs. Concentrations of MeSO{sub 2}-PCBs in liver were between 10.6 and 77 ng/g, lipid weight, approximately 250 times less than those of total PCBs. The MeSO{sub 2}-PCBs congeners retained in the liver were dominated by those having the methylsulfonyl group in the 3-position.

  19. Nitrogen cycling in the secondary nitrite maximum of the eastern tropical North Pacific off Costa Rica

    Science.gov (United States)

    Buchwald, Carolyn; Santoro, Alyson E.; Stanley, Rachel H. R.; Casciotti, Karen L.

    2015-12-01

    Nitrite is a central intermediate in the marine nitrogen cycle and represents a critical juncture where nitrogen can be reduced to the less bioavailable N2 gas or oxidized to nitrate and retained in a more bioavailable form. We present an analysis of rates of microbial nitrogen transformations in the oxygen deficient zone (ODZ) within the eastern tropical North Pacific Ocean (ETNP). We determined rates using a novel one-dimensional model using the distribution of nitrite and nitrate concentrations, along with their natural abundance nitrogen (N) and oxygen (O) isotope profiles. We predict rate profiles for nitrate reduction, nitrite reduction, and nitrite oxidation throughout the ODZ, as well as the contributions of anammox to nitrite reduction and nitrite oxidation. Nitrate reduction occurs at a maximum rate of 25 nM d-1 at the top of the ODZ, at the same depth as the maximum rate of nitrite reduction, 15 nM d-1. Nitrite oxidation occurs at maximum rates of 10 nM d-1 above the secondary nitrite maximum, but also in the secondary nitrite maximum, within the ODZ. Anammox contributes to nitrite oxidation within the ODZ but cannot account for all of it. Nitrite oxidation within the ODZ that is not through anammox is also supported by microbial gene abundance profiles. Our results suggest the presence of nitrite oxidation within the ETNP ODZ, with implications for the distribution and physiology of marine nitrite-oxidizing bacteria, and for total nitrogen loss in the largest marine ODZ.

  20. Influence of a Southern Shift of the ITCZ from Quick Scatterometer Data on the Pacific North Equatorial Countercurrent

    Institute of Scientific and Technical Information of China (English)

    WU Fanghua; LIN Pengfei; LIU Hailong

    2012-01-01

    By analyzing the climatologically averaged wind stress during 2000-2007,it is found that the easterly wind stress in the northern tropical Pacific Ocean from Quick Scatterometer (QSCAT) data was stronger than those from Tropical Atmosphere Ocean (TAO) data and from National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis I.As a result,the Intertropical Convergence Zone (ITCZ) in the Pacific Ocean is more southward in the QSCAT data than in the NCEP/NCAR data.Relative to the NCEP wind,the southern shift of the ITCZ in the QSCAT data led to negative anomaly of wind stress curl north of a latitude of 6°N.The negative anomaly results in downward Ekman pumping in the central Pacific.The excessive local strong easterly wind also contributes to the downward Ekman pumping.This downward Ekman pumping suppresses the thermocline ridge,reduces the meridional thermocline slope and weakens the North Equatorial Countercurrent (NECC).These effects were confirmed by numerical experiments using two independent ocean general circulation models (OGCMs).Furthermore,the excessive equatorial easterly wind stress was also found to contribute to the weaker NECC in the OGCMs.A comparison between the simulations and observation data indicates that the stronger zonal wind stress and its southern shift of QSCAT data in the ITCZ region yield the maximum strength of the simulated NECC only 33% of the magnitude derived from observation data and even led to a "missing" NECC in the western Pacific.

  1. Interannual relationships between the tropical sea surface temperature and summertime subtropical anticyclone over the western North Pacific

    Science.gov (United States)

    Chung, Pei-Hsuan; Sui, Chung-Hsiung; Li, Tim

    2011-07-01

    The interannual variability of the Western North Pacific Subtropical High (WNPSH) in boreal summer is investigated with the use of the NCEP/NCAR Reanalysis Data. The most significant change of the 500 hPa geopotential height field appears at the western edge of the WNPSH, with dominant 2-3 year and 3-5 year power spectrum peaks. The 2-3 year oscillation of the WNPSH and associated circulation and sea surface temperature (SST) patterns possess a coherent eastward propagating feature, with a warm SST anomaly (SSTA) and anomalous ascending motion migrating from the tropical Indian Ocean in the preceding autumn to the maritime continent in the concurrent summer of a strong WNPSH. A strong WNPSH is characterized by anomalous anticyclonic circulation and maximum subsidence in the western North Pacific (WNP). The anomalous WNPSH circulation has an equivalent barotropic vertical structure and resides in the sinking branch of the local Hadley circulation, triggered by enhanced convection over the maritime continent. A heat budget analysis reveals that the WNPSH is maintained by radiative cooling. The 3-5 year oscillation of the WNPSH exhibits a quasi-stationary feature, with a warm SSTA (anomalous ascending motion) located in the equatorial central eastern Pacific and Indian Ocean and a cold SSTA (anomalous descending motion) located in the western Pacific. The anomaly pattern persists from the preceding winter to the concurrent summer of a high WNPSH. The greatest descent is located to the southeast of the anomalous anticyclone center, where a baroclinic vertical structure is identified. The zonal phase difference and the baroclinic vertical structure suggest that the anomalous anticyclone on this timescale is a Rossby wave response to a negative latent heating associated with the persistent local cold SSTA. ECHAM4 model experiments further confirm that the 2-3 year mode is driven by the SSTA forcing over the maritime continent, while the 3-5 year mode is driven by the

  2. A Study of Transport and Impact Strength of Fukushima Nuclear Pollutants in the North Pacific Surface

    Institute of Scientific and Technical Information of China (English)

    FU Hongli; LI Wei; ZHANG Xuefeng; HAN Guijun; WANG Xidong; WU Xinrong; ZHANG Lianxin

    2014-01-01

    Based on the statistics of surface drifter data of 1979-2011 and the simulation of nuclear pollutant particulate move-ments simulated using high quality ocean reanalysis surface current dataset, the transport pathways and impact strength of Fuku-shima nuclear pollutants in the North Pacific have been estimated. The particulates are used to increase the sampling size and en-hance the representativeness of statistical results. The trajectories of the drifters and particulates are first examined to identify typical drifting pathways. The results show that there are three types of transport paths for nuclear pollutants at the surface: 1) most pollutant particles move eastward and are carried by the Kuroshio and Kuroshio-extension currents and reach the east side of the North Pacific after about 3.2-3.9 years;2) some particles travel with the subtropical circulation branch and reach the east coast of China after about 1.6 years according to one drifter trajectory and about 3.6 years according to particulate trajectories;3) a little of them travel with local, small scale circulations and reach the east coast of China after about 1.3-1.8 years. Based on the par-ticulates, the impact strength of nuclear pollutants at these time scales can be estimated according to the temporal variations of relative concentration combined with the radioactive decay rate. For example, Cesium-137, carried by the strong North Pacific current, mainly accumulates in the eastern North Pacific and its impact strength is 4%of the initial level at the originating Fuku-shima area after 4 years. Due to local eddies, Cesium-137 in the western North Pacific is 1%of the initial pollutant level after 1.5 years and continuously increases to 3%after 4 years. The vertical movement of radioactive pollutants is not taken into account in the present study, and the estimation accuracy would be improved by considering three-dimensional flows.

  3. Vertical structure variability and equatorial waves during central Pacific and eastern Pacific El Ninos in a coupled general circulation model

    Energy Technology Data Exchange (ETDEWEB)

    Dewitte, B.; Thual, S. [LEGOS/IRD, Toulouse (France); Choi, J.; An, S.I. [Yonsei University, Seoul (Korea, Republic of)

    2012-06-15

    Recent studies report that two types of El Nino events have been observed. One is the cold tongue El Nino or Eastern Pacific El Nino (EP El Nino), which is characterized by relatively large sea surface temperature (SST) anomalies in the eastern Pacific, and the other is the warm pool El Nino (a.k.a. 'Central Pacific El Nino' (CP El Nino) or 'El Nino Modoki'), in which SST anomalies are confined to the central Pacific. Here the vertical structure variability of the periods during EP and CP is investigated based on the GFDL{sub C}M2.1 model in order to explain the difference in equatorial wave dynamics and associated negative feedback mechanisms. It is shown that the mean stratification in the vicinity of the thermocline of the central Pacific is reduced during CP El Nino, which favours the contribution of the gravest baroclinic mode relatively to the higher-order slower baroclinic mode. Energetic Kelvin and first-meridional Rossby wave are evidenced during the CP El Nino with distinctive amplitude and propagating characteristics according to their vertical structure (mostly first and second baroclinic modes). In particular, the first baroclinic mode during CP El Nino is associated to the ocean basin mode and participates to the recharge process during the whole El Nino cycle, whereas the second baroclinic mode is mostly driving the discharge process through the delayed oscillator mechanism. This may explain that the phase transition from warm to neutral/cold conditions during the CP El Nino is delayed and/or disrupted compared to the EP El Nino. Our results have implications for the interpretation of the variability during periods of high CP El Nino occurrence like the last decade. (orig.)

  4. The Role of the Halted Baroclinic Mode at the Central Equatorial Pacific in El Ni(n)o Event

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The role of halted "baroclinic modes" in the central equatorial Pacific is analyzed. It is found that dominant anomaly signals corresponding to "baroclinic modes" occur in the upper layer of the equatorial Pacific, in a two-and-a-half layer oceanic model, in assimilated results of a simple OGCM and in the ADCP observation of TAO. A second "baroclinic mode" is halted in the central equatorial Pacific corresponding to a positive SST anomaly while the first "baroclinic mode" propagates eastwards in the eastern equatorial Pacific. The role of the halted second "baroclinic mode" in the central equatorial Pacific is explained by a staged ocean-atmosphere interaction mechanism in the formation of El Ni(n)o: the westerly bursts in boreal winter over the western equatorial Pacific generate the halted second "baroclinic mode" in the central equatorial Pacific, leading to the increase of heat content and temperature in the upper layer of the central Pacific which induces the shift of convection from over the western equatorial Pacific to the central equatorial Pacific; another wider, westerly anomaly burst is induced over the western region of convection above the central equatorial Pacific and the westerly anomaly burst generates the first "baroclinic mode"propagating to the eastern equatorial Pacific, resulting in a warm event in the eastern equatorial Pacific.The mechanism presented in this paper reveals that the central equatorial Pacific is a key region in detecting the possibility of ENSO and, by analyzing TAO observation data of ocean currents and temperature in the central equatorial Pacific, in predicting the coming of an El Ni(n)o several months ahead.

  5. Comparative Resilience in Five North Pacific Regional Salmon Fisheries

    Directory of Open Access Journals (Sweden)

    Courtland L. Smith

    2010-06-01

    Full Text Available Over the past century, regional fisheries for Pacific salmon (Oncorhynchus spp. have been managed primarily for their provisioning function, not for ecological support and cultural significance. We examine the resilience of the regional salmon fisheries of Japan, the Russian Far East, Alaska, British Columbia, and Washington-Oregon-California (WOC in terms of their provisioning function. Using the three dimensions of the adaptive cycle—capital, connectedness, and resilience—we infer the resilience of the five fisheries based on a qualitative assessment of capital accumulation and connectedness at the regional scale. In our assessment, we evaluate natural capital and connectedness and constructed capital and connectedness. The Russian Far East fishery is the most resilient, followed by Alaska, British Columbia, Japan, and WOC. Adaptive capacity in the fisheries is contingent upon high levels of natural capital and connectedness and moderate levels of constructed capital and connectedness. Cross-scale interactions and global market demand are significant factors in reduced resilience. Greater attention to ecological functioning and cultural signification has the potential to increase resilience in Pacific salmon ecosystems.

  6. Mesoscale cyclogenesis over the western north Pacific Ocean during TPARC

    Directory of Open Access Journals (Sweden)

    Christopher A. Davis

    2013-01-01

    Full Text Available Three cases of mesoscale marine cyclogenesis over the subtropics of the Western Pacific Ocean are investigated. Each case occurred during the THORPEX Pacific Asia Regional Campaign and Tropical Cyclone Structure (TCS-08 field phases in 2008. Each cyclone developed from remnants of disturbances that earlier showed potential for tropical cyclogenesis within the tropics. Two of the cyclones produced gale-force surface winds, and one, designated as a tropical cyclone, resulted in a significant coastal storm over eastern Japan. Development was initiated by a burst of organized mesoscale convection that consolidated and intensified the surface cyclonic circulation over a period of 12–24 h. Upper-tropospheric potential vorticity anomalies modulated the vertical wind shear that, in turn, influenced the periods of cyclone intensification and weakening. Weak baroclinicity associated with vertical shear was also deemed important in organizing mesoscale ascent and the convection outbreaks. The remnant tropical disturbances contributed exceptional water vapour content to higher latitudes that led to strong diabatic heating, and the tropical remnants contributed vorticity that was the seed of the development in the subtropics. Predictability of these events more than three days in advance appears to be minimal.

  7. 76 FR 56905 - The Central Valley Project, the California-Oregon Transmission Project, the Pacific Alternating...

    Science.gov (United States)

    2011-09-14

    ..., California; City of Lodi, California; City of Palo Alto, California; City of Santa Clara (dba Silicon Valley... September 14, 2011 Part III Department of Energy Western Area Power Administration The Central Valley... Administration The Central Valley Project, the California-Oregon Transmission Project, the Pacific...

  8. Intensified impact of northern tropical Atlantic SST on tropical cyclogenesis frequency over the western North Pacific after the late 1980s

    Science.gov (United States)

    Cao, Xi; Chen, Shangfeng; Chen, Guanghua; Wu, Renguang

    2016-08-01

    Previous studies suggest that spring SST anomalies over the northern tropical Atlantic (NTA) affect the tropical cyclone (TC) activity over the western North Pacific (WNP) in the following summer and fall. The present study reveals that the connection between spring NTA SST and following summer-fall WNP TC genesis frequency is not stationary. The influence of spring NTA SST on following summer-fall WNP TC genesis frequency is weak and insignificant before, but strong and significant after, the late 1980s. Before the late 1980s, the NTA SST anomaly-induced SST anomalies in the tropical central Pacific are weak, and the response of atmospheric circulation over the WNP is not strong. As a result, the connection between spring NTA SST and following summer-fall WNP TC genesis frequency is insignificant in the former period. In contrast, after the late 1980s, NTA SST anomalies induce pronounced tropical central Pacific SST anomalies through an Atlantic-Pacific teleconnection. Tropical central Pacific SST anomalies further induce favorable conditions for WNP TC genesis, including vertical motion, mid-level relative humidity, and vertical zonal wind shear. Hence, the connection between NTA SST and WNP TC genesis frequency is significant in the recent period. Further analysis shows that the interdecadal change in the connection between spring NTA SST and following summer-fall WNP TC genesis frequency may be related to the climatological SST change over the NTA region.

  9. Interdecadal shift in the western North Pacific Summer SST anomaly in the late 1980s

    Institute of Scientific and Technical Information of China (English)

    WU BingYi; ZHANG RenHe

    2007-01-01

    An interdecadal shift in summer (June-August) sea surface temperature (SST) variations during the period of 1968―2002 was identified in the late 1980s, which is characterized by a phase alternating from negative to positive phases of the leading mode of the empirical orthogonal function (EOF) analysis of the summer monthly mean SST in the Pacific domain 100°―180°E and 0°―40°N, accounting for 30.5% of the total variance. During the period of 1968―1987, the leading mode with a mean negative phase state (mean standard deviation = -0.586) controlled SST variability in the western North Pacific. Correspondingly, negative SST anomalies occupied the western North Pacific south of Japan and Chinese marginal seas. During the period of 1988―2002, the leading mode shifted to its strong positive polarity (mean standard deviation = 0.781), thus positive SST anomalies appeared in the western North Pacific. Accompanied by the interdecadal shift in summer mean SST, summer mean rainfall increased in southern and southeastern China during the late period, particularly in southeastern China where increase in summer mean rainfall exceeded 40 mm, at the 0.05 significance level.

  10. Pacific Decadal Variability and Central Pacific Warming El Niño in a Changing Climate

    Energy Technology Data Exchange (ETDEWEB)

    Di Lorenzo, Emanuele

    2015-02-27

    This research aimed at understanding the dynamics controlling decadal variability in the Pacific Ocean and its interactions with global-scale climate change. The first goal was to assess how the dynamics and statistics of the El Niño Southern Oscillation and the modes of Pacific decadal variability are represented in global climate models used in the IPCC. The second goal was to quantify how decadal dynamics are projected to change under continued greenhouse forcing, and determine their significance in the context of paleo-proxy reconstruction of long-term climate.

  11. Population structure of nuclear and mitochondrial DNA variation among humpback whales in the North Pacific.

    Science.gov (United States)

    Baker, C S; Medrano-Gonzalez, L; Calambokidis, J; Perry, A; Pichler, F; Rosenbaum, H; Straley, J M; Urban-Ramirez, J; Yamaguchi, M; von Ziegesar, O

    1998-06-01

    The population structure of variation in a nuclear actin intron and the control region of mitochondrial DNA is described for humpback whales from eight regions in the North Pacific Ocean: central California, Baja Peninsula, nearshore Mexico (Bahia Banderas), offshore Mexico (Socorro Island), southeastern Alaska, central Alaska (Prince Williams Sound), Hawaii and Japan (Ogasawara Islands). Primary mtDNA haplotypes and intron alleles were identified using selected restriction fragment length polymorphisms of target sequences amplified by the polymerase chain reaction (PCR-RFLP). There was little evidence of heterogeneity in the frequencies of mtDNA haplotypes or actin intron alleles due to the year or sex composition of the sample. However, frequencies of four mtDNA haplotypes showed marked regional differences in their distributions (phi ST = 0.277; P < 0.001; n = 205 individuals) while the two alleles showed significant, but less marked, regional differences (phi ST = 0.033; P < 0.013; n = 400 chromosomes). An hierarchical analysis of variance in frequencies of haplotypes and alleles supported the grouping of six regions into a central and eastern stock with further partitioning of variance among regions within stocks for haplotypes but not for alleles. Based on available genetic and demographic evidence, the southeastern Alaska and central California feeding grounds were selected for additional analyses of nuclear differentiation using allelic variation at four microsatellite loci. All four loci showed significant differences in allele frequencies (overall FST = 0.043; P < 0.001; average n = 139 chromosomes per locus), indicating at least partial reproductive isolation between the two regions as well as the segregation of mtDNA lineages. Although the two feeding grounds were not panmictic for nuclear or mitochondrial loci, estimates of long-term migration rates suggested that male-mediated gene flow was several-fold greater than female gene flow. These results

  12. Streamflow Measurements in North-Central Nebraska, November 2006

    Science.gov (United States)

    Peterson, Steven M.; Strauch, Kellan R.

    2007-01-01

    Streamflow measurements were made during November of 2006 in the Elkhorn and Loup River basins and selected streams in the Niobrara and Platte River basins in north-central Nebraska. At these 531 sites, flows ranging from no flow to 2,600 ft3/s were measured or observed. The data are presented in a table along with the quality of measurement and the method that was used. Maps show the location of the study area and the sites.

  13. North pacific right whale surveys conducted in the Bering Sea and North Pacific Ocean by Alaska Fisheries Science Center, National Marine Mammal Laboratory from 2007-08-01 to 2011-09-10 (NCEI Accession 0133935)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The North Pacific right whale (NPRW) was heavily hunted between the 17th and the 20th centuries. Protection was supposedly afforded by international treaties in the...

  14. Distant Influence of Kuroshio Eddies on North Pacific Weather Patterns?

    Science.gov (United States)

    Ma, Xiaohui; Chang, Ping; Saravanan, R.; Montuoro, Raffaele; Hsieh, Jen-Shan; Wu, Dexing; Lin, Xiaopei; Wu, Lixin; Jing, Zhao

    2015-12-01

    High-resolution satellite measurements of surface winds and sea-surface temperature (SST) reveal strong coupling between meso-scale ocean eddies and near-surface atmospheric flow over eddy-rich oceanic regions, such as the Kuroshio and Gulf Stream, highlighting the importance of meso-scale oceanic features in forcing the atmospheric planetary boundary layer (PBL). Here, we present high-resolution regional climate modeling results, supported by observational analyses, demonstrating that meso-scale SST variability, largely confined in the Kuroshio-Oyashio confluence region (KOCR), can further exert a significant distant influence on winter rainfall variability along the U.S. Northern Pacific coast. The presence of meso-scale SST anomalies enhances the diabatic conversion of latent heat energy to transient eddy energy, intensifying winter cyclogenesis via moist baroclinic instability, which in turn leads to an equivalent barotropic downstream anticyclone anomaly with reduced rainfall. The finding points to the potential of improving forecasts of extratropical winter cyclones and storm systems and projections of their response to future climate change, which are known to have major social and economic impacts, by improving the representation of ocean eddy-atmosphere interaction in forecast and climate models.

  15. Data-driven prediction strategies for low-frequency patterns of North Pacific climate variability

    CERN Document Server

    Comeau, Darin; Giannakis, Dimitrios; Majda, Andrew J

    2015-01-01

    The North Pacific exhibits patterns of low-frequency variability on the intra-annual to decadal time scales, which manifest themselves in both model data and the observational record, and prediction of such low-frequency modes of variability is of great interest to the community. While parametric models, such as stationary and non-stationary autoregressive models, possibly including external factors, may perform well in a data-fitting setting, they may perform poorly in a prediction setting. Ensemble analog forecasting, which relies on the historical record to provide estimates of the future based on past trajectories of those states similar to the initial state of interest, provides a promising, nonparametric approach to forecasting that makes no assumptions on the underlying dynamics or its statistics. We apply such forecasting to low-frequency modes of variability for the North Pacific sea surface temperature and sea ice concentration fields extracted through Nonlinear Laplacian Spectral Analysis. We find ...

  16. Interannual variability and future projection of summertime ocean wave heights in the western North Pacific

    Directory of Open Access Journals (Sweden)

    W. Sasaki

    2006-10-01

    Full Text Available A 70-yr (from 1985–1995 to 2055–2065 change of decadal mean summertime extreme significant wave heights (SWH in the western North Pacific under CO2-induced global warming condition is projected. For this purpose, possible atmospheric fields under future global warming are derived from 10-yr time-slice experiments using a T106 AGCM. The future changes of SWH are assessed by an empirical approach, where possible changes of SWH are estimated using a linear regression model which shows an empirical relationship between SWH anomalies and an eastward shift of the monsoon trough. It is projected that SWH increases by up to ~0.4 m over a wide area of the western North Pacific.

  17. Tropical Pacific influences on the North Atlantic Thermohaline Circulation

    Directory of Open Access Journals (Sweden)

    M. Latif

    2003-06-01

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

  18. Relationships between ENSO and East Asian-western North Pacific monsoon: observations versus 18 CMIP5 models

    Science.gov (United States)

    Wu, B.

    2014-12-01

    The relationships between ENSO and the East Asian-western North Pacific monsoon during ENSO mature winter and decaying summer are studied by examining the pre-industrial control runs of 18 global climate models (GCMs) that participated in the phase five of the Coupled Model Intercomparison Project (CMIP5). In the observation, the tropical western North Pacific (WNP) is dominated by an anomalous anticyclone (cyclone) during El Niño (La Niña) mature winter, referred to as WNPAC (WNPC). WNPAC is asymmetric with WNPC. Multi-model assessments support the idea that the asymmetry results from the combined effects of the asymmetric remote forcing from the equatorial central-eastern Pacific and the asymmetric local sea surface temperature (SST) anomalies. It has been proposed that the asymmetric circulation anomalies over the tropical WNP have a contribution to the asymmetric decaying rates between El Niño and La Niña. The mechanism works in the CMIP5 models. Those models that can (cannot) simulate the asymmetry between WNPAC and WNPC tend to reproduce ENSO with asymmetric (symmetric) decaying rates. In the observation, WNPAC maintains throughout El Niño decaying summer. The maintenance of WNPAC primarily relies on the local forcing of underlying cold SST anomalies in the early summer, remaining from preceding winter and spring, whereas to remote forcing from the tropical Indian Ocean in the late summer. The two mechanisms are reproduced by the multi-model ensemble mean. The scatter diagrams for the CMIP5 models demonstrate that the response of WNPAC to the remote forcing from the tropical Indian Ocean intensifies from June to July, concurring with the establishment of the climatological WNP monsoon trough.

  19. Prediction of dominant intraseasonal modes in the East Asian-western North Pacific summer monsoon

    Science.gov (United States)

    Oh, Hyoeun; Ha, Kyung-Ja

    2016-10-01

    Intraseasonal monsoon prediction is the most imperative task, but there remains an enduring challenge in climate science. The present study aims to provide a physical understanding of the sources for prediction of dominant intraseasonal modes in the East Asian-western North Pacific summer monsoon (EA-WNPSM): pre-Meiyu&Baiu, Changma&Meiyu, WNPSM, and monsoon gyre modes classified by the self-organizing map analysis. Here, we use stepwise regression to determine the predictors for the four modes in the EA-WNPSM. The selected predictors are based on the persistent and tendency signals of the sea surface temperature (SST)/2m air temperature and sea level pressure fields, which reflect the asymmetric response to the El Niño Southern Oscillation (ENSO) and the ocean and land surface anomalous conditions. For the pre-Meiyu&Baiu mode, the SST cooling tendency over the western North Pacific (WNP), which persists into summer, is the distinguishing contributor that results in strong baroclinic instability. A major precursor for the Changma&Meiyu mode is related to the WNP subtropical high, induced by the persistent SST difference between the Indian Ocean and the western Pacific. The WNPSM mode is mostly affected by the Pacific-Japan pattern, and monsoon gyre mode is primarily associated with a persistent SST cooling over the tropical Indian Ocean by the preceding ENSO signal. This study carries important implications for prediction by establishing valuable precursors of the four modes including nonlinear characteristics.

  20. Sequential megafaunal collapse in the North Pacific Ocean: An ongoing legacy of industrial whaling?

    OpenAIRE

    Springer, A. M.; Estes, J. A.; van Vliet, G. B.; T. M. Williams; Doak, D F; Danner, E. M.; Forney, K. A.; Pfister, B.

    2003-01-01

    Populations of seals, sea lions, and sea otters have sequentially collapsed over large areas of the northern North Pacific Ocean and southern Bering Sea during the last several decades. A bottom-up nutritional limitation mechanism induced by physical oceanographic change or competition with fisheries was long thought to be largely responsible for these declines. The current weight of evidence is more consistent with top-down forcing. Increased predation by killer whales probably drove the sea...

  1. Contrasting Marine Carbon Monoxide Budget in the North Pacific and the Amundsen Sea

    Science.gov (United States)

    Kwon, Young Shin; Siek Rhee, Tae

    2016-04-01

    Carbon monoxide (CO) is a trace gas that affects the global climate indirectly by participating in the atmospheric chemistry. Although in many studies it is estimated to be produced fast in the surface ocean from the photolysis of chromophoric dissolved organic carbon (CDOM), also it decreases considerably by the microbial oxidation and the vertical mixing in water column. Therefore, the strength of oceanic source to the atmosphere is not so considerable. To investigate how the CO budget in the mixed layer governs the CO emission from sea to air, we conducted the underway measurements of CO, the dark incubation experiments, and the measurements of CDOM absorbance during two expeditions in the Amundsen Sea and the North Pacific in summer season of 2012. Dark incubation experiments revealed that microbial consumption rate in the North Pacific was 2.7 nM d‑1whilst 1.2 nM d‑1 in the Amundsen Sea, which is ca. 2.3 times smaller. However, CO production rate was as much as about 40 times higher in the North Pacific (1 nM d‑1) due mainly to sea-ice albedo in the Amundsen Sea. It seems that this different CO budget between the two regions causes different amplitude of diurnal variation of dissolved CO. That is, compared to the Amundsen Sea, CO is produced faster in daytime and removed faster all day in the North Pacific where the sinusoidal amplitude of CO is larger. In both regions, ˜97% of CO is estimated to be consumed by microbes, and sea-to-air flux density calculated from the underway measurements was insignificant in terms of the total atmospheric reservoir. Our observations indicate that the source strength of the ocean was evenly weak regardless of the scale of CO budget in the ocean. That is, marine biota can be thought as a main control of CO in the atmosphere, the important trace gas for the global climate change.

  2. Tempo-spatial patterns of bacterial community composition in the western North Pacific Ocean

    OpenAIRE

    Kataoka, Takafumi; Hodoki, Yoshikuni; Suzuki, Koji; Saito, Hiroaki; Higashi, Seigo

    2009-01-01

    In the western North Pacific, where subarctic Oyashio waters encounter subtropical Kuroshio waters, phylotype composition of heterotrophic bacteria was estimated by denaturing gradient gel electrophoresis (DGGE) of PCR-amplified bacterial 16S ribosomal DNA. Total bacterial abundance was also measured by flow cytometry. The study area was divided into four water masses: coastal, Oyashio, Kuroshio, and the Kuroshio-Oyashio transition. Abundances of heterotrophic bacteria in the Oyashio, Kuroshi...

  3. Pelagic Ostracods of the Genera Halocypris and Felia (Subfamily Halocypridinae) from the North Pacific

    OpenAIRE

    Chavtur, Vladimir G.; STOVBUN, GALINA G.

    2008-01-01

    Morphology of Halocypris inflata (Dana, 1853), H. pelagica Claus, 1890, Felia cornuta (Müller, 1906) and F. bicornis (Müller, 1906) is examined with North Pacific materials and compared with previous records. Complete synonymy and corrected distribution were given for these species. Halocypris angustifrontalis, new species is described in detail. It differs from known species of this genus by its very large size and the structure of the coxal segment of the mandible. Keys to all species of bo...

  4. Impact of tropical Pacific variability on the mean North Atlantic thermohaline circulation

    OpenAIRE

    Semenov, Vladimir; Latif, Mojib

    2006-01-01

    A series of 500 years long coupled general circulation model simulations has been performed, in which the sea surface temperatures (SSTs) in different tropical oceans have been prescribed from climatology. A statistically significant reduction by about one Sverdrup of the meridional overturning circulation (MOC) in the North Atlantic was found when the tropical Pacific SSTs do not vary interannually. Anomalously low salinities originating in the tropical Atlantic due to increased precipitatio...

  5. AFSC/RACE/GAP/Conrath: Notes on the Reproductive Biology of Female Salmon Sharks in the Eastern North Pacific Ocean

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Little information has previously been published on the reproductive biology of the salmon shark in the Eastern North Pacific ocean. This data set incorporates...

  6. The Moisture Structure of ISO in Western North Pacific Revealed by AIRS

    Institute of Scientific and Technical Information of China (English)

    TAO Li; FU Xiouhua; WANG Bin

    2009-01-01

    Using the humidity profiles from the Atmospheric Infrared Sounder (AIRS) dataset, rainfall from the Tropical Rainfall Measuring Mission (TRMM) Global Precipitation Index (GPI), and surface winds from QuickSCAT (QSCAT) as well as SST from the Advanced Microwave Scanning Radiometer for NASA's Earth Observing System (AMSR_E), we analyzed the structure of summer intraseasonal oscillation (ISO) over the western North Pacific region in 2003-2004. We find that the signal of 20-90-day oscillations in the western North Pacific originates from the equatorial Indian Ocean, and propagates eastward to Philippine Sea and then moves northwestward to South China. The AIRS humidity data reveal that the boundary-layer moisture leads the mid-troposphere moisture during the ISO propagation. The positive SST anomaly may play an important role to moistening the boundary-layer, which preconditions the ISO propagation. Therefore, the intraseasonal SST anomaly could positively feed back to the atmosphere through moistening the boundary-layer, destabilizing the troposphere, and contributing to the northwestward propagation of the ISO in western North Pacific. On the other hand, the salient feature that the boundary-layer moisture anomaly leads mid-troposphere moisture does not exist in ECMWF/TOGA analysis.

  7. New predictors and a new prediction model for the typhoon frequency over western North Pacific

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In this paper, the impacts of the atmospheric circulation during boreal winter-spring on the western North Pacific (WNP) typhoon frequency (WNPTF) are studied. Several new factors in winter-spring influencing the typhoon frequency were identified, including the sea ice cover in the North Pacific and the North Pacific oscillation. Based on these results, the multi-linear regression was applied to establishing a new forecast model for the typhoon frequency by using the datasets of 1965―1999. The forecast model shows a high correlation coefficient (0.79) between the model simulated and the actual typhoon frequencies in the period of 1965―1999. The forecast model also exhibits reasonable hindcasts for the typhoon frequencies for the years 2000―2006. Therefore, this work demonstrates that the new predictors are significant for the prediction of the interannual variability of the WNPTF, which could be potentially used in the operational seasonal forecast of the typhoon frequency in the WNP to get a more physically based operational prediction model and higher forecast skill.

  8. Reexamination of tropical cyclone heat potential in the western North Pacific

    Science.gov (United States)

    Wada, Akiyoshi

    2016-06-01

    Tropical cyclone heat potential (TCHP), a measure of the oceanic heat content from the surface to the 26°C isotherm depth, has been widely used for tropical cyclone (TC) forecasting and climatological studies. This study reexamines TCHP and the relation to TCs in the western North Pacific in view of the importance of the oceanic reference isothermal depth. Original TCHP is not applicable around the Kuroshio and Kuroshio Extension regions because the value is zero where sea surface temperature is below 26°C. Therefore, this study proposes an improved version of TCHP as new TCHP under relatively weak baroclinic conditions in the atmospheric environment during the TC season from July to November. The alternative oceanic reference isothermal temperature (TRef24) used to calculate new TCHP is determined based on 2 m dew point temperature or 24°C when it is lower than 24°C. We examine the relationship between TCHPs and changes in best track central pressures during the previous 6 h from 2002 to 2012. Relatively high new TCHP is associated with deep oceanic isotherm depth and the decrease in TRef24 around the Kuroshio region from September to November. Case studies for Typhoons Maemi (2003), Songda (2004), and Roke (2011) reveal that TCs could intensify/redevelop around the Ryukyu Islands over warm eddies revealed by high new TCHP, where original TCHP is relatively low. The results indicate that new TCHP can be a metric for TC intensification caused by wind-induced surface heat exchange processes associated with atmospheric temperature and moisture near the surface and upper ocean stratification.

  9. Physical and underway data collected aboard the ROGER REVELLE during cruise AMAT02RR in the North Pacific Ocean and South Pacific Ocean from 2005-09-03 to 2006-03-03 (NCEI Accession 0155592)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0155592 includes physical and underway data collected aboard the ROGER REVELLE during cruise AMAT02RR in the North Pacific Ocean and South Pacific...

  10. 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...

  11. 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...

  12. 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...

  13. Relative importance of tropical SST anomalies in maintaining the Western North Pacific anomalous anticyclone during El Niño to La Niña transition years

    Science.gov (United States)

    Chen, Zesheng; Wen, Zhiping; Wu, Renguang; Lin, Xiaobin; Wang, Jiabao

    2016-02-01

    This study investigates the relative importance of tropical Indian Ocean warming (IOW) and equatorial central to eastern Pacific cooling (EPC) in sustaining an anomalous Western North Pacific anticyclone (WNPAC) during the transition from an El Niño in the preceding winter to a La Niña in the subsequent summer through a suite of numerical experiments. The numerical results indicate that the WNPAC is maintained by a combined effect of IOW and EPC during the La Niña developing years. The contribution of IOW in maintaining the WNPAC sustains from spring to early summer, but appears to weaken after that as IOW decays. The role of IOW is via an eastward-propagating Kelvin wave induced Ekman divergence mechanism. The decay of IOW is because of reduction in downward solar radiation associated with above normal precipitation in situ. As the cooling develops over central to eastern Pacific from spring to summer, EPC starts to contribute to the maintenance of the WNPAC during summer through stimulating a Rossby wave response to its northwest. In this study, we have identified that the cooling over the central to eastern Pacific plays an important role in sustaining the WNPAC during La Niña developing summers. This finding may help improve the prediction of the East Asian summer monsoon, which is closely associated with the WNPAC.

  14. Nitrate + nitrite content (concentration), phosphate, and silicate collected from NOAA Ship Oscar Elton Sette in the North Pacific Ocean from 2008-03-26 to 2011-03-24 (NCEI Accession 0129883)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Laboratory analysis of water samples collected aboard NOAA Ship Oscar Elton Sette along a 158°W transect from 26°-36°N in the central North Pacific. Laboratory...

  15. CRED Reson 8101 multibeam backscatter data of Palmyra Atoll, Pacific Remote Island Areas, Central 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 the lagoon, shelf, and slope environments of Palmyra Atoll, Pacific Island Areas, Central...

  16. Magnetostratigraphic correlation of the Upper Cretaceous System in the North Pacific

    Science.gov (United States)

    Kodama, K.

    2003-06-01

    Magnetostratigraphic data for Upper Cretaceous sedimentary strata in widely separated regions of the North Pacific, including Japan, Far East Russia and western North America, are reviewed in terms of calibration to the geomagnetic polarity time scale and regional correlation. A series of normal and reversed polarity zones are recognized in the Upper Cretaceous strata in Shikoku and Hokkaido, Japan, and South Sakhalin, Far East Russia. Combined magnetostratigraphic and biostratigraphic correlation has assigned these zones to the Late Cretaceous geomagnetic polarity chrons including C31r through C33r and the Cretaceous long normal interval. Corresponding geomagnetic reversals have been documented from the Upper Cretaceous successions of the Western Interior of North America, in combination with high-resolution ammonite biostratigraphy and radiometric age dates. Biostratigraphy of the Great Valley Sequence in California is also well-defined, but there is only one reversed interval that can be correlated with polarity chron C33r. The most complete record of polarity reversals in South Sakhalin would provide an integrated reference scheme which can be of significant use not only to correlate dissimilar faunal assemblages of disparate regions in the North Pacific, but also to contribute to a global definition of Upper Cretaceous stage boundaries.

  17. Denali Ice Core Record of North Pacific Hydroclimate, Temperature and Atmospheric Circulation over the Past Millennium

    Science.gov (United States)

    Osterberg, E. C.; Wake, C. P.; Kreutz, K. J.; Winski, D.; Ferris, D. G.; Introne, D.; Campbell, S.; Birkel, S. D.

    2015-12-01

    While tree ring and lake sediment core studies have revealed a great deal about North Pacific (e.g. Alaska) surface temperature variability over the past millennium, we do not have an equivalent understanding of North Pacific hydroclimate variability or temperatures at high elevations. A millennial-length precipitation proxy record is needed to place late 20th century Alaskan precipitation increases into longer context, and to evaluate hydroclimate changes during the Little Ice Age and Medieval Climate Anomaly. High-elevation summer temperature records would be valuable for understanding the sensitivity of Alaskan glaciers to past warm and cool periods. Here we present an overview of the new Denali Ice Core record collected from the summit plateau (4000 m a.s.l.) of Mt. Hunter (63° N, 151° W) in Denali National Park, Alaska. Two parallel ice cores were collected to bedrock (208 m in length) in May-June 2013, sampled using the Dartmouth continuous melter system, and analyzed for major ions, trace elements, particle concentration and size distribution, and stable isotope ratios at Dartmouth and the Universities of Maine and New Hampshire. The cores are dated using robust annual oscillations in dust elements, methanesulfonate, ammonium, and stable isotopes, and validated using major volcanic eruptions recorded as sulfate, chloride and heavy metal spikes, and the 1963 nuclear weapons testing 137Cs spike. Preliminary analyses indicate a significant increase in both summer temperature and annual accumulation over the 20th century, and significant relationships with major ocean-atmospheric modes including the Pacific Decadal Oscillation. We compare the new Denali record to the Eclipse Icefield and Mt. Logan ice core records and develop composite records of North Pacific hydroclimate and atmospheric circulation variability over the past millennium.

  18. Impact of Low-Level Southerly Surges on Mixed Rossby Gravity Waves over the Central Pacific.

    Science.gov (United States)

    Fukutomi, Y.

    2014-12-01

    This study examines dynamical impacts of lower-tropospheric southerly wind surges originating in midlatitudes of the Southern Hemisphere (SH) on the development of mixed Rossby gravity (MRG) waves over the central Pacific during June-August 1979-2012, through the statistical analysis of the JRA-55 products and NOAA outgoing long wave radiation data. The central Pacific MRG waves are identified by an extended EOF (EEOF) analysis on 2-8-day filtered daily 850-hPa meridional wind anomalies during June-August 1979-2012. Composite analysis based on the leading EEOF time coefficients is able to capture the development of the MRG waves associated with a southerly surge originating in the SH extratropics. As a weak clockwise gyre as a part of an off-equatorial easterly wavetrain moves eastward and southeastward from the off-equatorial eastern Pacific into the equatorial central Pacific, the southerly surge penetrates into the equatorial tropics at around 150W. Then, the clockwise gyre develops into a MRG-type gyre over the central Pacific. A transition from an easterly wave-type gyre into a MRG-type gyre occurs associated with the southerly surge. The southerly surge forms a cross-equatorial flow on the western flank of the MRG-type gyre. The gyre is amplified when the southerly surge reaches the equatorial tropics. At the same time, convection coupled with the MRG-type gyre is enhanced. The southerly surges are originated in the midlatitude South Pacific, and they are induced by synoptic-scale baroclinic disturbances propagating along the SH midlatitude westerly jet. An eddy vorticity budget analysis indicates that the southerly surge plays an important role in spinning up the MRG-type gyre through transient advection of absolute vorticiy. A case study of a MRG-wave event in mid-July 2006 also illustrates development of a MRG wave associated with the southerly surge and an easterly wave-to-MRG wave transition.

  19. Systematic status of wild Canis in North-central Texas

    Science.gov (United States)

    Mech, L. David; Nowak, Ronald M.

    2010-01-01

    Skulls of wild Canis collected 2003–2004 in north-central Texas are morphometrically similar to a series taken there and in nearby areas in 1964–1971, which was considered to represent a population of Coyotes (C. latrans) modified through introgression from Red Wolves (C. rufus). A few of the new specimens closely resemble small examples of Red Wolves. Such affinity is supported by authoritative examination of living and videotaped animals. The persistence of influence of Red Wolves, long after presumed extirpation through hybridization and human persecution, may be relevant to wolf conservation.

  20. Interannual and decadal variability and trends in upper ocean temperatures in the North Pacific Ocean

    International Nuclear Information System (INIS)

    Temperature profiles from the surface to 400 m deployed over the North Pacific Ocean for the 45 years from 1950--1994 are mapped onto a coarse grid each month, allowing trends in the upper ocean temperature to be estimated. Only temperature profiles distributed from 20 degree N-60 degree N are used, these subjected to rigorous scientific quality control. Two parameters are chosen to be representative of the upper ocean thermal structure; i.e., sea surface temperature (SST) and heat storage over the upper 400 m (HS400). Mapping of SST and HS400 is conducted monthly, with optimal interpolation utilizing a priori estimates of the covariance structure of the anomalous fields determined by White. This yields a time sequence of 540 monthly maps for each parameter over this 45-year period. Examining these time sequences for decadal variability and trends finds their magnitude and sign to change substantially as a function of geographical location over the North Pacific Ocean. For example, all along the west coast of North America, both SST and HS400 warmed during the past 45 years. But, in the middle of the North Pacific Ocean, both parameters cooled over this period. The average SST and HS400 over the entire domain from 20 degree-60 degree N did not show a trend. Rather, decadal variability dominated the time sequence, with the 1950's colder than normal, the 1960's near normal, the 1970's warmer than normal, the 1980's colder than normal, and the 1990's warmer than normal. This natural decadal variability obscures any possible anthropogenic warming due to increased greenhouse gas concentrations in the atmosphere over this period

  1. Investigating the 'Iron Hypothesis' in the North Pacific: Trans-Pacific Dust and Methanesulfonate (MSA) in the Denali Ice Core, Alaska

    Science.gov (United States)

    Saylor, P. L.; Osterberg, E. C.; Winski, D.; Ferris, D. G.; Koffman, B. G.; Kreutz, K. J.; Wake, C. P.; Campbell, S. W.

    2015-12-01

    Oceanic deposition of Asian-sourced, Iron-rich dust particulate has been linked to enhanced phytoplankton productivity in regions of the Pacific Ocean. High Nutrient Low Chlorophyll (HNLC) ocean regions, such as the North Pacific, are hypothesized to play a significant role in changing atmospheric CO­2 concentrations on glacial-interglacial timescales. Phytoplankton blooms generate methanesulfonate (MSA), an atmospheric oxidation product of dimethylsulfide (DMS) that is readily aerosolized and deposited in nearby glacial ice. In the summer of 2013, an NSF-funded team from Dartmouth College and the Universities of Maine and New Hampshire collected two 1000 year-long parallel ice cores to bedrock from the summit plateau of Mount Hunter in Denali National Park, Alaska (62.940° N, 151.088° W, 3912 m elevation). The Mt. Hunter ice core site is well situated to record changes in trans-Pacific dust flux and MSA emissions in the North Pacific. Here we investigate the history of dust flux to Denali over the last millennium using major and trace element chemistry and microparticle concentration and size distribution data from the Mt. Hunter cores. We evaluate potential controlling mechanisms on Denali dust flux including conditions at Asian dust sources (storminess, wind speed, precipitation), the strength of the Aleutian Low, and large-scale climate modes such as the El Niño-Southern Oscillation and the Pacific Decadal Oscillation. We also evaluate the Mt. Hunter record for relationships between dust flux and MSA concentrations to investigate whether dust fertilization enhanced North Pacific phytoplankton production over the past 1000 years. Future work will create a composite North Pacific dust record using new and existing Mt. Logan ice core records to evaluate these relationships over the entire Holocene.

  2. Iron fertilisation by Asian dust influences North Pacific sardine regime shifts

    Science.gov (United States)

    Qiu, Yongsong

    2015-05-01

    Forcing factors and mechanisms underlying multidecadal variability in the production of the world's major fish stocks are one of the great mysteries of the oceans. The Japanese and California sardine are species that exhibit the regime shifts. It is shown in the present work that during two periods of frequent Asian dust events over the last 100 years, sardines on opposite sides of the Pacific Ocean only flourished under a dust-active regime. The earlier such regime that peaked in the 1930s was strong, and it brought synchronous changes in the two species that were linked to the frequency of Asian dust events. However, there is an apparent mismatch in the rise and fall of abundance between the two species in the current dust-active regime. The massive increase in Japanese sardine stock in the 1970s was related to high levels of ocean precipitation and strong winter mixing, whereas the stock collapse since 1988 has been attributed to diminished winter mixing. High levels of ocean precipitation in the western North Pacific effectively cause wet deposition of Asian dust and enhance Japanese sardine stock, whereas it reduces dust flux that can be transported to the eastern North Pacific, delaying the increase of California sardine stock. Analysis further indicates that productivity of Japanese sardine stock is jointly controlled by wet deposition of Asian dust and winter mixing, which supplies macronutrients from depth. California sardine productivity is inversely related to precipitation in the western North Pacific and is positively affected by precipitation off western North America. This indicates that Asian dust influx dominates productivity of the species because of iron-limited ocean productivity in the California sardine ranges. The analysis suggests that dust regime shifts influence shifts in sardine productivity regimes and that iron input from Asian dust during trans-Pacific transport is directly responsible. It appears that in addition to enhancing

  3. Synchronous seasonal change in fin whale song in the North Pacific.

    Science.gov (United States)

    Oleson, Erin M; Širović, Ana; Bayless, Alexandra R; Hildebrand, John A

    2014-01-01

    Fin whale (Balaenoptera physalus) song consists of down-swept pulses arranged into stereotypic sequences that can be characterized according to the interval between successive pulses. As in blue (B. musculus) and humpback whales (Megaptera novaeangliae), these song sequences may be geographically distinct and may correlate with population boundaries in some regions. We measured inter-pulse intervals of fin whale songs within year-round acoustic datasets collected between 2000 and 2006 in three regions of the eastern North Pacific: Southern California, the Bering Sea, and Hawaii. A distinctive song type that was recorded in all three regions is characterized by singlet and doublet inter-pulse intervals that increase seasonally, then annually reset to the same shorter intervals at the beginning of each season. This song type was recorded in the Bering Sea and off Southern California from September through May and off Hawaii from December through April, with the song interval generally synchronized across all monitoring locations. The broad geographic and seasonal occurrence of this particular fin whale song type may represent a single population broadly distributed throughout the eastern Pacific with no clear seasonal migratory pattern. Previous studies attempting to infer population structure of fin whales in the North Pacific using synchronous individual song samples have been unsuccessful, likely because they did not account for the seasonal lengthening in song intervals observed here. PMID:25521493

  4. Synchronous seasonal change in fin whale song in the North Pacific.

    Directory of Open Access Journals (Sweden)

    Erin M Oleson

    Full Text Available Fin whale (Balaenoptera physalus song consists of down-swept pulses arranged into stereotypic sequences that can be characterized according to the interval between successive pulses. As in blue (B. musculus and humpback whales (Megaptera novaeangliae, these song sequences may be geographically distinct and may correlate with population boundaries in some regions. We measured inter-pulse intervals of fin whale songs within year-round acoustic datasets collected between 2000 and 2006 in three regions of the eastern North Pacific: Southern California, the Bering Sea, and Hawaii. A distinctive song type that was recorded in all three regions is characterized by singlet and doublet inter-pulse intervals that increase seasonally, then annually reset to the same shorter intervals at the beginning of each season. This song type was recorded in the Bering Sea and off Southern California from September through May and off Hawaii from December through April, with the song interval generally synchronized across all monitoring locations. The broad geographic and seasonal occurrence of this particular fin whale song type may represent a single population broadly distributed throughout the eastern Pacific with no clear seasonal migratory pattern. Previous studies attempting to infer population structure of fin whales in the North Pacific using synchronous individual song samples have been unsuccessful, likely because they did not account for the seasonal lengthening in song intervals observed here.

  5. Whales, Dolphins, and Porpoises of the Eastern North Pacific and Adjacent Arctic Waters: A Guide to Their Identification.

    Science.gov (United States)

    Leatherwood, Stephen; And Others

    This field guide is designed to permit observers to identify the cetaceans (whales, dolphins, and porpoises) they see in the waters of the eastern North Pacific, including the Gulf of California, Hawaii, and the western Arctic of North America. The animals described are grouped not by scientific relationships but by similarities in appearance in…

  6. Geologic framework, age, and lithologic characteristics of the North Park Formation in North Park, north-central Colorado

    Science.gov (United States)

    Shroba, Ralph R.

    2016-10-18

    Deposits of the North Park Formation of late Oligocene and Miocene age are locally exposed at small, widely spaced outcrops along the margins of the roughly northwest-trending North Park syncline in the southern part of North Park, a large intermontane topographic basin in Jackson County in north-central Colorado. These outcrops suggest that rocks and sediments of the North Park Formation consist chiefly of poorly consolidated sand, weakly cemented sandstone, and pebbly sandstone; subordinate amounts of pebble conglomerate; minor amounts of cobbly pebble gravel, siltstone, and sandy limestone; and rare beds of cobble conglomerate and altered tuff. These deposits partly filled North Park as well as a few small nearby valleys and half grabens. In North Park, deposits of the North Park Formation probably once formed a broad and relatively thick sedimentary apron composed chiefly of alluvial slope deposits (mostly sheetwash and stream-channel alluvium) that extended, over a distance of at least 150 kilometers (km), northwestward from the Never Summer Mountains and northward from the Rabbit Ears Range across North Park and extended farther northwestward into the valley of the North Platte River slightly north of the Colorado-Wyoming border. The maximum preserved thickness of the formation in North Park is about 550 meters near the southeastern end of the North Park syncline.The deposition of the North Park Formation was coeval in part with local volcanism, extensional faulting, development of half grabens, and deposition of the Browns Park Formation and Troublesome Formation and was accompanied by post-Laramide regional epeirogenic uplift. Regional deposition of extensive eolian sand sheets and loess deposits, coeval with the deposition of the North Park Formation, suggests that semiarid climatic conditions prevailed during the deposition of the North Park Formation during the late Oligocene and Miocene.The North Park Formation locally contains a 28.1-mega-annum (Ma

  7. Lg Coda Variations in North-Central Iran

    Directory of Open Access Journals (Sweden)

    Mojtaba Naghavi

    2012-01-01

    Full Text Available Ground motion records in north-central Iran have been used in order to obtain the Lg coda , using stack spectral ratio method. The lateral variations in 0 and its frequency dependence are estimated in the 0.3–7.0 Hz frequency range which led to =267(±32×0.71(±0.14. The observed variations in quality factor show low values of 0 in western part of the study region where bounded by relatively high values in southern and northern parts. Since the seismicity of the study area is quite shallow the obtained results can be attributed to the upper 30 km of the crust. The Damavand volcano and its surrounding region also exhibit variations in the value of 0 which result in low and intermediate values of 0 in western and eastern parts, respectively. Current seismicity in Damavand is mostly confined to its southwestern part, whereas our results proved to possess low values of 0. In general, most of factor variations can be attributed to the lateral heterogeneity as well as the severity of the crustal velocity gradient, and as expected the north-central Iran is well inferred as a tectonically active region.

  8. The continental margin is a key source of iron to the HNLC North Pacific Ocean

    Energy Technology Data Exchange (ETDEWEB)

    Lam, P.J.; Bishop, J.K.B

    2008-01-15

    Here we show that labile particulate iron and manganese concentrations in the upper 500m of the Western Subarctic Pacific, an iron-limited High Nutrient Low Chlorophyll (HNLC) region, have prominent subsurface maxima between 100-200 m, reaching 3 nM and 600 pM, respectively. The subsurface concentration maxima in particulate Fe are characterized by a more reduced oxidation state, suggesting a source from primary volcagenic minerals such as from the Kuril/Kamchatka margin. The systematics of these profiles suggest a consistently strong lateral advection of labile Mn and Fe from redox-mobilized labile sources at the continental shelf supplemented by a more variable source of Fe from the upper continental slope. This subsurface supply of iron from the continental margin is shallow enough to be accessible to the surface through winter upwelling and vertical mixing, and is likely a key source of bioavailable Fe to the HNLC North Pacific.

  9. A model of loggerhead sea turtle (Caretta caretta habitat and movement in the oceanic North Pacific.

    Directory of Open Access Journals (Sweden)

    Melanie Abecassis

    Full Text Available Habitat preferences for juvenile loggerhead turtles in the North Pacific were investigated with data from two several-year long tagging programs, using 224 satellite transmitters deployed on wild and captive-reared turtles. Animals ranged between 23 and 81 cm in straight carapace length. Tracks were used to investigate changes in temperature preferences and speed of the animals with size. Average sea surface temperatures along the tracks ranged from 18 to 23 °C. Bigger turtles generally experienced larger temperature ranges and were encountered in warmer surface waters. Seasonal differences between small and big turtles suggest that the larger ones dive deeper than the mixed layer and subsequently target warmer surface waters to rewarm. Average swimming speeds were under 1 km/h and increased with size for turtles bigger than 30 cm. However, when expressed in body lengths per second (bl s(-1, smaller turtles showed much higher swimming speeds (>1 bl s (-1 than bigger ones (0.5 bl s(-1. Temperature and speed values at size estimated from the tracks were used to parameterize a habitat-based Eulerian model to predict areas of highest probability of presence in the North Pacific. The model-generated habitat index generally matched the tracks closely, capturing the north-south movements of tracked animals, but the model failed to replicate observed east-west movements, suggesting temperature and foraging preferences are not the only factors driving large-scale loggerhead movements. Model outputs could inform potential bycatch reduction strategies.

  10. Holocene Pacific - North American plate interaction in southern Alaska: implications for the Yakataga seismic gap.

    Science.gov (United States)

    Lahr, J.C.; Plafker, G.

    1980-01-01

    The St. Elias, Alaska, earthquake (magnitude 7.1 MS) on February 28, 1979, occurred along the complex Pacific-North American plate boundary between Yakutat Bay and Prince William Sound, rupturing only a fraction of the seismic gap identified in that region. To aid in evaluating the potential for, and likely site of, a future earthquake occurring in the remainder of the gap, we have formulated a kinematic model of neotectonic deformation in southern Alaska from available geologic and seismic data. In this model the part of the North American plate bordering on the Gulf of Alaska is divided into three subblocks, which are partially coupled to the Pacific plate. On the basis of the model, the gap-filling rupture or ruptures would most likely be along the north-dipping thrust faults of the Pamplona zone between Icy Bay and the eastern end of the Aleutian Trench. If the accumulated strain of 3.8 m postulated for this region were released suddenly in one event involving the remainder of the gap, the result would be an earthquake as large as magnitude 8. -Authors

  11. Constraints on the magnitude of the deglacial migration of the ITCZ in the Central Equatorial Pacific Ocean

    Science.gov (United States)

    Reimi, Maria A.; Marcantonio, Franco

    2016-11-01

    Accurate paleo-latitudinal reconstructions of the Intertropical Convergence Zone (ITCZ) are necessary for understanding tropical hydroclimate and atmospheric circulation. Paleoclimate models and records suggest that as global temperatures increase, the ITCZ should migrate towards the warmer hemisphere. Many uncertainties remain regarding the magnitude of this migration, and few studies have focused on the Central Equatorial Pacific (CEP). Here, we use eolian dust records recovered from three locations in the CEP to address changes in dust provenance across the paleo ITCZ since the last glacial maximum (LGM). Radiogenic isotope compositions of Nd and Pb show that dust delivered to the CEP was sourced mainly from two regions: East Asia and South America. From these data we deduced that since Marine Oxygen Isotope Stage 2 (MIS2) the ITCZ has migrated north to its modern position, being displaced by as much as 7°, to as little as 2.5°. We find that the ITCZ migrated further north during the early Holocene (∼9 kyr), reaching its position furthest north during the mid-Holocene warm interval (∼7 kyr), based on an increase in South American dust at the northernmost sites.

  12. Ecoregional analysis of nearshore sea-surface temperature in the North Pacific.

    Directory of Open Access Journals (Sweden)

    Meredith C Payne

    Full Text Available The quantification and description of sea surface temperature (SST is critically important because it can influence the distribution, migration, and invasion of marine species; furthermore, SSTs are expected to be affected by climate change. To better understand present temperature regimes, we assembled a 29-year nearshore time series of mean monthly SSTs along the North Pacific coastline using remotely-sensed satellite data collected with the Advanced Very High Resolution Radiometer (AVHRR instrument. We then used the dataset to describe nearshore (<20 km offshore SST patterns of 16 North Pacific ecoregions delineated by the Marine Ecoregions of the World (MEOW hierarchical schema. Annual mean temperature varied from 3.8°C along the Kamchatka ecoregion to 24.8°C in the Cortezian ecoregion. There are smaller annual ranges and less variability in SST in the Northeast Pacific relative to the Northwest Pacific. Within the 16 ecoregions, 31-94% of the variance in SST is explained by the annual cycle, with the annual cycle explaining the least variation in the Northern California ecoregion and the most variation in the Yellow Sea ecoregion. Clustering on mean monthly SSTs of each ecoregion showed a clear break between the ecoregions within the Warm and Cold Temperate provinces of the MEOW schema, though several of the ecoregions contained within the provinces did not show a significant difference in mean seasonal temperature patterns. Comparison of these temperature patterns shared some similarities and differences with previous biogeographic classifications and the Large Marine Ecosystems (LMEs. Finally, we provide a web link to the processed data for use by other researchers.

  13. Structure and dynamics of decadal anomalies in the wintertime midlatitude North Pacific ocean-atmosphere system

    Science.gov (United States)

    Fang, Jiabei; Yang, Xiu-Qun

    2015-12-01

    The structure and dynamics of decadal anomalies in the wintertime midlatitude North Pacific ocean-atmosphere system are examined in this study, using the NCEP/NCAR atmospheric reanalysis, HadISST SST and Simple Ocean Data Assimilation data for 1960-2010. The midlatitude decadal anomalies associated with the Pacific Decadal Oscillation are identified, being characterized by an equivalent barotropic atmospheric low (high) pressure over a cold (warm) oceanic surface. Such a unique configuration of decadal anomalies can be maintained by an unstable ocean-atmosphere interaction mechanism in the midlatitudes, which is hypothesized as follows. Associated with a warm PDO phase, an initial midlatitude surface westerly anomaly accompanied with intensified Aleutian low tends to force a negative SST anomaly by increasing upward surface heat fluxes and driving southward Ekman current anomaly. The SST cooling tends to increase the meridional SST gradient, thus enhancing the subtropical oceanic front. As an adjustment of the atmospheric boundary layer to the enhanced oceanic front, the low-level atmospheric meridional temperature gradient and thus the low-level atmospheric baroclinicity tend to be strengthened, inducing more active transient eddy activities that increase transient eddy vorticity forcing. The vorticity forcing that dominates the total atmospheric forcing tends to produce an equivalent barotropic atmospheric low pressure north of the initial westerly anomaly, intensifying the initial anomalies of the midlatitude surface westerly and Aleutian low. Therefore, it is suggested that the midlatitude ocean-atmosphere interaction can provide a positive feedback mechanism for the development of initial anomaly, in which the oceanic front and the atmospheric transient eddy are the indispensable ingredients. Such a positive ocean-atmosphere feedback mechanism is fundamentally responsible for the observed decadal anomalies in the midlatitude North Pacific ocean

  14. Structure and dynamics of decadal anomalies in the wintertime midlatitude North Pacific ocean-atmosphere system

    Science.gov (United States)

    Fang, Jiabei; Yang, Xiu-Qun

    2016-09-01

    The structure and dynamics of decadal anomalies in the wintertime midlatitude North Pacific ocean-atmosphere system are examined in this study, using the NCEP/NCAR atmospheric reanalysis, HadISST SST and Simple Ocean Data Assimilation data for 1960-2010. The midlatitude decadal anomalies associated with the Pacific Decadal Oscillation are identified, being characterized by an equivalent barotropic atmospheric low (high) pressure over a cold (warm) oceanic surface. Such a unique configuration of decadal anomalies can be maintained by an unstable ocean-atmosphere interaction mechanism in the midlatitudes, which is hypothesized as follows. Associated with a warm PDO phase, an initial midlatitude surface westerly anomaly accompanied with intensified Aleutian low tends to force a negative SST anomaly by increasing upward surface heat fluxes and driving southward Ekman current anomaly. The SST cooling tends to increase the meridional SST gradient, thus enhancing the subtropical oceanic front. As an adjustment of the atmospheric boundary layer to the enhanced oceanic front, the low-level atmospheric meridional temperature gradient and thus the low-level atmospheric baroclinicity tend to be strengthened, inducing more active transient eddy activities that increase transient eddy vorticity forcing. The vorticity forcing that dominates the total atmospheric forcing tends to produce an equivalent barotropic atmospheric low pressure north of the initial westerly anomaly, intensifying the initial anomalies of the midlatitude surface westerly and Aleutian low. Therefore, it is suggested that the midlatitude ocean-atmosphere interaction can provide a positive feedback mechanism for the development of initial anomaly, in which the oceanic front and the atmospheric transient eddy are the indispensable ingredients. Such a positive ocean-atmosphere feedback mechanism is fundamentally responsible for the observed decadal anomalies in the midlatitude North Pacific ocean

  15. A 290-a record of atmospheric circulation over the North Pacific from a Mt. Logan ice core, Yukon Territory

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Calibrations between sodium (Na+) concentrations from a Mt. Logan ice core and sea level pressure (SLP) series show that Na+ concentrations are closely correlated with the autumn-time (SeptemberOctober-November) Aleutian low (AleuLow). A deepening of the AleuLow strengthens the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. The Mt. Logan Na+ record is used to develop a 292 a (1688~1979) reconstruction of the AleuLow revealing a dramatic intensification of atmospheric circulation over the North Pacific region since the 20th century. Mean SLP of the AleuLow was about 1 hPa lower during the 20th century than during prior periods. The strongest deepening of the AleuLow appeared in the 1950s. Significant correlations are also found between the Mt. Logan AleuLow proxy series and the Pacific decadal oscillation (PDO) and Pacific circulation (PC) index during the 20th century. Evolutionary spectral analysis of the proxy record shows significant periodicities from 15 to 30 a consistent with PDO fluctuations and the bidecadal oscillation of North Pacific atmosphere-ocean circulation. A period of 11 a in the AleuLow record may be associated with the Schwabe 11-a cycle of sunspot activity. Additional longer ice core records from this region will aid in the efforts to further understand the climatic change over the North Pacific region.

  16. Harmful algal blooms in the PICES region of the North Pacific

    OpenAIRE

    2002-01-01

    Foreword Background and objectives [pdf, 0.84 MB] Country reviews and status reports Section I. Western North Pacific Japan Yasuwo Fukuyo, Ichiro Imai, Masaaki Kodama and Kyoichi Tamai Red tides and harmful algal blooms in Japan [pdf, 0.7 MB] People's Republic of China Tian Yan, Ming-Jiang Zhou and Jing-Zhong Zou A national report of HABs in China [pdf, 0.24 MB] Republic of Korea Sam Geun Lee, Hak Gyoon Kim, Eon Seob Cho and Chang Kyu Lee Harmful ...

  17. Interdecadal variability of the tropospheric biennial oscillation in the western North Pacific

    Institute of Scientific and Technical Information of China (English)

    Zheng Bin; Lin Ai-Lan; Gu De-Jun; Li Chun-Hui

    2008-01-01

    The observed tropospheric biennial oscillation (TBO) in the western North Pacific (WNP) monsoon region has an interdecadal variability with a period of 40-50 yr.That suggests a weaker effect of the TBO on the East Asia followed by a stronger one.A simple analytic model was designed to investigate the mechanism of the interdecadal variability of the TBO.The results indicated that a local TBO air-sea system not only supports the TBO variability in the WNP monsoon region but also produces an interdecadal variability of the TBO.

  18. Contrasting the eastern Pacific El Niño and the central Pacific El Niño: process-based feedback attribution

    Science.gov (United States)

    Hu, Xiaoming; Yang, Song; Cai, Ming

    2016-10-01

    This paper examines the roles of radiative and non-radiative air-sea coupled thermodynamic processes in modifying sea surface temperature (SST) anomalies driven by (air-sea coupled) oceanic dynamic processes, focusing on their contributions to the key differences between the eastern Pacific (EP) El Niño and the central Pacific (CP) El Niño. The attribution is achieved by decomposing SST anomalies into partial temperature anomalies due to individual processes using a coupled atmosphere-surface climate feedback-response analysis method. Oceanic processes induce warming from the central to the eastern equatorial Pacific and cooling over the western basin with a maximum warming center in the central Pacific for both types of El Niño. The processes that act to oppose the oceanic process-induced SST anomalies are surface latent heat flux, sensible heat flux, cloud, and atmospheric dynamic feedbacks, referred to as negative-feedback processes. The cooling due to each of the four negative-feedback processes is the strongest in the region where the initial warming due to oceanic processes is the largest. Water-vapor feedback is the sole process that acts to enhance the initial warming induced by oceanic processes. The increase in atmospheric water vapor over the eastern Pacific is much stronger for the EP El Niño than for the CP El Niño. It is the strong water-vapor feedback over the eastern Pacific and the strong negative feedbacks over the central equatorial Pacific that help to relocate the maximum warming center from the central Pacific to the eastern basin for the EP El Niño.

  19. Distribution and biology of epipelagic animals in the northern North Pacific Ocean and adjacent seas-I. Fishes and squids in the southern Okhotsk Sea and western North Pacific Ocean off the Kuril Islands in the autumn of 1993

    OpenAIRE

    Nagasawa, Kazuya; Ueno, Yasuhiro; Azuma, Teruo; OGURA, Miki(College of National Rehabilitation Center for the Disabled); Startsev, Alexander V.; Ivanova, Irena M.; Morris, John F. T.

    1996-01-01

    A surface-trawl survey was conducted by the R/V Kaiyo mare in the southern Okhotsk Sea and western North Pacific Ocean off the Kuril Islands in October and November 1993. The distributions and abundances of the species caught are described and discussed. Twenty-four fish species (1 lamprey, 1 shark, and 22 teleosts) and one squid species were identified. Juvenile Pacific salmon (6 species of the genus Oncorhynchus) were the most abundant, followed by myctophids, juvenile arabesque greenling (...

  20. Subtropical Potential Vorticity Intrusion Drives Increasing Tropospheric Ozone over the Tropical Central Pacific

    Science.gov (United States)

    Nath, Debashis; Chen, Wen; Graf, Hans-F.; Lan, Xiaoqing; Gong, Hainan; Nath, Reshmita; Hu, Kaiming; Wang, Lin

    2016-01-01

    Drawn from multiple reanalysis datasets, an increasing trend and westward shift in the number of Potential Vorticity intrusion events over the Pacific are evident. The increased frequency can be linked to a long-term trend in upper tropospheric equatorial westerly wind and subtropical jets during boreal winter to spring. These may be resulting from anomalous warming and cooling over the western Pacific warm pool and the tropical eastern Pacific, respectively. The intrusions brought dry and ozone rich air of stratospheric origin deep into the tropics. In the tropical upper troposphere, interannual ozone variability is mainly related to convection associated with El Niño/Southern Oscillation. Zonal mean stratospheric overturning circulation organizes the transport of ozone rich air poleward and downward to the high and midlatitudes leading there to higher ozone concentration. In addition to these well described mechanisms, we observe a long-term increasing trend in ozone flux over the northern hemispheric outer tropical (10–25°N) central Pacific that results from equatorward transport and downward mixing from the midlatitude upper troposphere and lower stratosphere during PV intrusions. This increase in tropospheric ozone flux over the Pacific Ocean may affect the radiative processes and changes the budget of atmospheric hydroxyl radicals. PMID:26868836

  1. Fertility and pacification among the Mekranoti of Central Brazil.

    Science.gov (United States)

    Werner, D

    1983-06-01

    Demographic data from 3 different historical periods of the Mekranoti-Kayapo Indians of Central Brazil were used to examine various explanations for historical changes in fertility among this group. The possible effects of warfare on Mekranoti fertility were also examined since warfare has had an important role in many preindustrial societies. The Mekranoti are a group of 285 relatively unacculturated Indians living in a single village in southern Para, Brazil. As in precontact days, their economy is based on slash and burn agriculture, hunting, and fishing. To assess Mekranoti fertility, pregnancy histories collected from all women 15 years or older as of December 1976 were used. In precontact years a woman who survived to age 50 could expect to give birth 6.5 times. During the contact years this average dropped to 5.6 and in the postcontact period it soared to almost 8.5. The drop in Mekranoti fertility from precontact to contact years corresponds with an increase in mortality. The direction of these changes would support a "health" argument about fertility, but the degrees of change do not. Whereas mortality increased markedly after 1955, fertility fell only slightly. The data are not consistent with the view that changes in lactation periods are responsible for fertility changes. The number of uses of contraceptives per reproductive woman year did not not vary much in the different historical periods and certainly could not account for differences in Mekranoti fertility. The data suggest that fertility changes over Mekranoti history may be due in part to sexual abstinence resulting either from postpartum sexual taboos or, more importantly, from a lack of husbands. Sex imbalances resulting from high male mortality in warfare and subsequent disruption of marriages by disease and death left many women without spouses for long periods of time. The findings are consistent with other studies that found lower fertility associated with male absence. The Mekranoti are

  2. Thermal Evolution of the North-Central Gulf Coast

    Science.gov (United States)

    Nunn, Jeffrey A.; Scardina, Allan D.; Pilger, Rex H., Jr.

    1984-12-01

    The subsidence history of the North Louisiana Salt Basin, determined from well data, indicates that the region underwent extension during rifting and has since passively subsided due to conductive cooling of the lithosphere. Timing of the rifting event is consistent with opening of the Gulf of Mexico during Late Triassic to Early Jurassic time. Crustal extension by a factor of 1.5 to 2 was computed from "tectonic" subsidence curves. However, data from the early subsidence history are insufficient to distinguish between uniform and nonuniform extension of the lithosphere. The magnitude of extension is in good agreement with total sediment and crustal thicknesses from seismic refraction data in the adjacent Central Mississippi Salt Basin. The temperature distribution within the sediments is calculated using a simple heat conduction model. Temperature and subsidence effects of thermal insulation by overlying sediments are included. The computed temperature distribution is in good agreement with bottom hole temperatures measured in deep wells. Temperature histories predicted for selected stratigraphic horizons within the North Louisiana Salt Basin suggest that thermal conditions have been favorable for hydrocarbon generation in the older stata. Results from a two-dimensional heat conduction model suggest that a probable cause for the early formation of the adjacent uplifts is lateral heat conduction from the basin. Rapid extension of the lithosphere underneath areas with horizontal dimensions of 50-100 km produces extremely rapid early subsidence due to lateral heat conduction. The moderate subsidence rate observed in the North Louisiana Salt Basin during the Jurassic and Early Cretaceous suggests slow extension over a long period of time.

  3. Diagnostic Analysis on a Regional Rainstorm Weather in North-central Henan Province

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The research aimed to analyze a regional rainstorm weather process in north-central Henan Province. [Method] Based on the conventional meteorological observation data and the rainfall data of Henan Meteorological Station, the diagnostic analysis of atmospheric thermodynamics and dynamics on a rainstorm weather process in north-central Henan Province on July 19, 2010 was carried out. The characteristics of physical quantity field and the evolution of weather situation in north-central Henan Provi...

  4. On meridional circulation and heat budget of the troposphere over the Equatorial Central Pacific

    OpenAIRE

    Hastenrath, Stefan L.

    2011-01-01

    The existence of an equatorial dry zone in the Central Pacific enclosed between moister belts in both hemispheres is borne out by rainfall measurements and daily ESSA III and ESSA V cloud mosaics. The tropospheric wind regime is studied mainly on the basis of aerological soundings during the Line Islands Experiment (LIE) in spring 1967 and observations of earlier periods. During LIE, upper-tropospheric Westerlies extend continuously across the equator. In the lower layers, Easterlies dominate...

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

    Science.gov (United States)

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

    2011-05-01

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

  6. Intensification of North Pacific intermediate water ventilation during the Younger Dryas

    Science.gov (United States)

    Ohkushi, Ken'ichi; Hara, Naoki; Ikehara, Minoru; Uchida, Masao; Ahagon, Naokazu

    2016-04-01

    Modern North Pacific intermediate water (NPIW) is formed in the mixed water region where the Oyashio and Kuroshio currents meet. The source for cooling and freshening of NPIW is intermediate water in the Okhotsk Sea. The Okhotsk intermediate water outflows to the open Pacific, forming the Oyashio intermediate water by mixing with the subarctic gyre water. In the Oyashio region, the intermediate water originating from the Okhotsk Sea flows mainly at depths shallower than 500 m. On the other hand, ventilation of intermediate water in the subarctic Pacific during the deglaciation remains a topic of debate. In this study, foraminiferal δ18O and δ13C signatures were determined in a dated sediment core collected at 777 m water depth to evaluate the intensity and depth distribution of the source of NPIW since the last deglaciation in the Oyashio region. Benthic foraminiferal δ18O increased by 0.3-0.4‰ from the end of the Bølling/Ållerød warm episode to the Younger Dryas cold episode, suggesting intermediate water cooling. Consistent with this trend, benthic δ13C values point to decreased nutrient contents during the cold event. Conversely, benthic δ18O signatures from a nearby core site at a water depth of 1,366 m did not show such cooling. These results suggest that cold intermediate water originating from the north was actively ventilated at depths of at least 700-800 m, and possibly even 1,200 m during the Younger Dryas, implying that NPIW ventilation was thicker and deeper than under modern conditions.

  7. Variability in the correlation between Asian dust storms and chlorophyll a concentration from the North to Equatorial Pacific.

    Science.gov (United States)

    Tan, Sai-Chun; Yao, Xiaohong; Gao, Hui-Wang; Shi, Guang-Yu; Yue, Xu

    2013-01-01

    A long-term record of Asian dust storms showed seven high-occurrence-frequency centers in China. The intrusion of Asian dust into the downwind seas, including the China seas, the Sea of Japan, the subarctic North Pacific, the North Pacific subtropical gyre, and the western and eastern Equatorial Pacific, has been shown to add nutrients to ocean ecosystems and enhance their biological activities. To explore the relationship between the transported dust from various sources to the six seas and oceanic biological activities with different nutrient conditions, the correlation between monthly chlorophyll a concentration in each sea and monthly dust storm occurrence frequencies reaching the sea during 1997-2007 was examined in this study. No correlations were observed between dust and chlorophyll a concentration in the dust sources and many sea areas, suggesting a link between dust and chlorophyll a concentration in those seas. However, the correlation coefficients were highly variable. In general, the correlation coefficients (0.54-0.63) for the Sea of Japan were highest, except for that between the subarctic Pacific and the Taklimakan Desert, where it was as high as 0.7. For the >50 m China seas and the North Pacific subtropical gyre, the correlation coefficients were in the range 0.32-0.57. The correlation coefficients for the western and eastern Equatorial Pacific were relatively low (dust sources, the transport pathways, the dust deposition, the nutrient conditions of oceans, and the probability of dust storms reaching the seas. PMID:23460892

  8. Pacific sleeper shark Somniosus pacificus trophic ecology in the eastern North Pacific Ocean inferred from nitrogen and carbon stable-isotope ratios and diet.

    Science.gov (United States)

    Courtney, D L; Foy, R

    2012-04-01

    Stable-isotope ratios of nitrogen (δ¹⁵N) and lipid-normalized carbon (δ¹³C') were used to examine geographic and ontogenetic variability in the trophic ecology of a high latitude benthopelagic elasmobranch, the Pacific sleeper shark Somniosus pacificus. Mean muscle tissue δ¹³C' values of S. pacificus differed significantly among geographic regions of the eastern North Pacific Ocean. Linear models identified significant ontogenetic and geographic variability in muscle tissue δ¹⁵N values of S. pacificus. The trophic position of S. pacificus in the eastern North Pacific Ocean estimated here from previously published stomach-content data (4·3) was within the range of S. pacificus trophic position predicted from a linear model of S. pacificus muscle tissue δ¹⁵N (3·3-5·7) for fish of the same mean total length (L(T) ; 201·5 cm), but uncertainty in predicted trophic position was very high (95% prediction intervals ranged from 2·9 to 6·4). The relative trophic position of S. pacificus determined here from a literature review of δ¹⁵N by taxa in the eastern North Pacific Ocean was also lower than would be expected based on stomach-content data alone when compared to fishes, squid and filter feeding whales. Stable-isotope analysis revealed wider variability in the feeding ecology of S. pacificus in the eastern North Pacific Ocean than shown by diet data alone, and expanded previous conclusions drawn from analyses of stomach-content data to regional and temporal scales meaningful for fisheries management.

  9. Pacific sleeper shark Somniosus pacificus trophic ecology in the eastern North Pacific Ocean inferred from nitrogen and carbon stable-isotope ratios and diet.

    Science.gov (United States)

    Courtney, D L; Foy, R

    2012-04-01

    Stable-isotope ratios of nitrogen (δ¹⁵N) and lipid-normalized carbon (δ¹³C') were used to examine geographic and ontogenetic variability in the trophic ecology of a high latitude benthopelagic elasmobranch, the Pacific sleeper shark Somniosus pacificus. Mean muscle tissue δ¹³C' values of S. pacificus differed significantly among geographic regions of the eastern North Pacific Ocean. Linear models identified significant ontogenetic and geographic variability in muscle tissue δ¹⁵N values of S. pacificus. The trophic position of S. pacificus in the eastern North Pacific Ocean estimated here from previously published stomach-content data (4·3) was within the range of S. pacificus trophic position predicted from a linear model of S. pacificus muscle tissue δ¹⁵N (3·3-5·7) for fish of the same mean total length (L(T) ; 201·5 cm), but uncertainty in predicted trophic position was very high (95% prediction intervals ranged from 2·9 to 6·4). The relative trophic position of S. pacificus determined here from a literature review of δ¹⁵N by taxa in the eastern North Pacific Ocean was also lower than would be expected based on stomach-content data alone when compared to fishes, squid and filter feeding whales. Stable-isotope analysis revealed wider variability in the feeding ecology of S. pacificus in the eastern North Pacific Ocean than shown by diet data alone, and expanded previous conclusions drawn from analyses of stomach-content data to regional and temporal scales meaningful for fisheries management. PMID:22497395

  10. Assessment of tsunami hazards for the Central American Pacific coast from southern Mexico to northern Peru

    OpenAIRE

    B. Brizuela; Armigliato, A.; S. Tinti

    2014-01-01

    Central America (CA), from Guatemala to Panama, has been struck by at least 52 tsunamis between 1539 and 2013, and in the extended region from Mexico to northern Peru (denoted as ECA, Extended Central America in this paper) the number of recorded tsunamis in the same time span is more than 100, most of which were triggered by earthquakes located in the Middle American Trench that runs parallel to the Pacific coast. The most severe event in the catalogue is the tsunami that o...

  11. Bundled slaty cleavage in laminated argillite, north-central minnesota

    Science.gov (United States)

    Southwick, D.L.

    1987-01-01

    Exceptional bundled slaty cleavage (defined herein) has been found in drill cores of laminated, folded, weakly metamorphosed argillite at several localities in the early Proterozoic Animikie basin of north-central Minnesota. The cleavage domains are more closely spaced within the cleavage bundles than outside them, the mean tectosilicate grain size of siltstone layers, measured normal to cleavage, is less in the cleavage bundles than outside them, and the cleavage bundles are enriched in opaque phases and phyllosilicates relative to extra-bundle segments. These facts suggest that pressure solution was a major factor in bundle development. If it is assumed that opaque phases have been conserved during pressure solution, the modal differences in composition between intra-bundle and extra-bundle segments of beds provide a means for estimating bulk material shortening normal to cleavage. Argillite samples from the central part of the Animikie basin have been shortened a minimum of about 22%, as estimated by this method. These estimates are similar to the shortening values derived from other strain markers in other rock types interbedded with the argillite, and are also consistent with the regional pattern of deformation. ?? 1987.

  12. North Pacific Mesoscale Coupled Air-Ocean Simulations Compared with Observations

    Energy Technology Data Exchange (ETDEWEB)

    Koracin, Darko; Cerovecki, Ivana; Vellore, Ramesh; Mejia, John; Hatchett, Benjamin; McCord, Travis; McLean, Julie; Dorman, Clive

    2013-04-11

    Executive summary The main objective of the study was to investigate atmospheric and ocean interaction processes in the western Pacific and, in particular, effects of significant ocean heat loss in the Kuroshio and Kuroshio Extension regions on the lower and upper atmosphere. It is yet to be determined how significant are these processes are on climate scales. The understanding of these processes led us also to development of the methodology of coupling the Weather and Research Forecasting model with the Parallel Ocean Program model for western Pacific regional weather and climate simulations. We tested NCAR-developed research software Coupler 7 for coupling of the WRF and POP models and assessed its usability for regional-scale applications. We completed test simulations using the Coupler 7 framework, but implemented a standard WRF model code with options for both one- and two-way mode coupling. This type of coupling will allow us to seamlessly incorporate new WRF updates and versions in the future. We also performed a long-term WRF simulation (15 years) covering the entire North Pacific as well as high-resolution simulations of a case study which included extreme ocean heat losses in the Kuroshio and Kuroshio Extension regions. Since the extreme ocean heat loss occurs during winter cold air outbreaks (CAO), we simulated and analyzed a case study of a severe CAO event in January 2000 in detail. We found that the ocean heat loss induced by CAOs is amplified by additional advection from mesocyclones forming on the southern part of the Japan Sea. Large scale synoptic patterns with anomalously strong anticyclone over Siberia and Mongolia, deep Aleutian Low, and the Pacific subtropical ridge are a crucial setup for the CAO. It was found that the onset of the CAO is related to the breaking of atmospheric Rossby waves and vertical transport of vorticity that facilitates meridional advection. The study also indicates that intrinsic parameterization of the surface fluxes

  13. Influence of climatic warming in the Southem and Northem Hemisphere on the tropical cyclone over the western North Pacific Ocean

    Institute of Scientific and Technical Information of China (English)

    TIAN Rong-xiang; WENG Huan-xin

    2006-01-01

    Based on analyzing the surface air temperature series in the Southern and Northern Hemisphere and the tropical cyclone (TC) over the western North Pacific Ocean, the relationships between climatic warming and the frequency and intensity of tropical cyclone are investigated. The results showed that with the climatic warming in both hemispheres, the frequency of the tropical cyclone over the western North Pacific Ocean reduces and its intensity weakens simultaneously. A possible explanation might be that the cold air invasion from the Southern Hemisphere weakens due to global warming.

  14. Temperature, salinity, and nutrients data from bottle, CTD, and XBT casts from the JOHN P. TULLY and other vessels in the North Atlantic and North Pacific Oceans from 03 August 1959 to 01 July 2001 (NODC Accession 0000664)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bottle, CTD, and XBT data were collected in the North Atlantic and North Pacific Oceans from the John P. Tully and other vessels from 03 August 1959 to 01 July...

  15. Temperature, salinity, and nutrients data from CTD, MBT, and bottle casts in the Arctic, North Atlantic and North Pacific Oceans from the SACKVILLE and other platforms from 1928-05-12 to 1998-11-03 (NODC Accession 0000448)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — CTD, MBT, bottle and other data were collected in the Arctic, North Atlantic, and North Pacific Oceans from the SACKVILLE and other platforms from 12 May 1928 to 03...

  16. Temperature, salinity, and nutrients data from bottle, CTD, and XBT casts in the Arctic, North Atlantic, and North Pacific Oceans from the ANTON DOHRN and other platforms from 02 July 1916 to 28 January 1999 (NODC Accession 0000677)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bottle, CTD, and XBT data were collected in the Arctic, North Atlantic, and North Pacific Oceans from the ANTON DOHRN and other vessels from 02 July 1916 to 28...

  17. Transport process of Pu isotope in marginal seas of the western North Pacific Ocean

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Masatoshi [Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, Hirosaki, 036-8564, Aomori (Japan); Zheng, Jian [Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, 263-8555, Chiba (Japan)

    2014-07-01

    Significant quantities of Pu isotopes have been released into the marine environment as the result of atmospheric nuclear weapons testing. Most radionuclides globally dispersed in atmospheric nuclear weapons testing were released into the environment during the 1950's and 1960's. In the western North Pacific Ocean, the principal source can be further distinguished as two distinct sources of Pu: close-in tropospheric fallout from nuclear weapons testing at the Pacific Proving Grounds (PPG) in the Marshall Islands and global stratospheric fallout. Since the {sup 240}Pu/{sup 239}Pu atom ratio is characteristic for the Pu emission source, information on Pu isotopic signature is very useful to better understand the transport process in the oceans and to identify the sources of Pu. The mean atom ratio of {sup 240}Pu/{sup 239}Pu from the global stratospheric fallout is 0.180 ±0.014 based on soil sample data, whereas that from close-in tropospheric fallout from the PPG is 0.33 - 0.36. The {sup 240}Pu/{sup 239}Pu atom ratios in seawater samples collected in marginal seas of the western North Pacific Ocean will provide important and useful data for understanding the process controlling Pu transport and for distinguishing future Pu sources. The objectives of this study were to measure the {sup 239+240}Pu concentrations and {sup 240}Pu/{sup 239}Pu atom ratios in seawater from the Sea of Okhotsk, Japan Sea, South China Sea and Sulu Sea and to discuss the transport process of Pu. Large-volume seawater samples (250 L each) were collected from the surface to the bottom in marginal seas of the western North Pacific Ocean with acoustically triggered quadruple PVC sampling bottles during the R/V Hakuho-Maru cruise. The {sup 239}Pu and {sup 240}Pu concentrations and {sup 240}Pu/{sup 239}Pu atom ratios were measured with a double-focusing SF-ICP-MS, which was equipped with a guard electrode to eliminate secondary discharge in the plasma and to enhance overall sensitivity. In

  18. Distributions of dissolved organic and inorganic carbon and radiocarbon in the eastern North Pacific continental margin

    Science.gov (United States)

    Bauer, James E.; Druffel, Ellen R. M.; Wolgast, David M.; Griffin, Sheila; Masiello, Caroline A.

    Temporal variations in the natural radiocarbon ( 14C) signatures of dissolved organic and inorganic carbon (DOC and DIC, respectively) in seawater have been studied previously (Druffel, E.R.M., Bauer, J.E., Williams, P.M., Griffin, S., Wolgast, D.M., 1996. Seasonal variability of radiocarbon in particulate organic carbon in the northeast Pacific. J. Geophys. Res. 101, 20 543-20 552; Bauer, J.E., Druffel, E.R.M., Williams, P.M., Wolgast, D.M., Griffin, S., 1998. Temporal variability in dissolved organic carbon and radiocarbon in the eastern North Pacific Ocean. J. Geophys. Res. 103, 2867-2882) at a long-term time-series station (Sta. M: 32°N, 123W) in the eastern North Pacific located at the eastern edge of the North Pacific abyssal plain. In June 1995 a transect was made from Sta. M inshore to approximately 500 m depth in order to evaluate the distributions of 14C in DOC and DIC from the abyssal plain to the upper continental slope. Concentrations and Δ 14C values of DOC in mixed layer waters (25 and 85 m) decreased toward the upper slope. In deeper waters, concentrations and Δ 14C values were in general similar at all three sites. Differences in DOC concentrations and Δ 14C-DOC between Sta. M and the rise and upper slope sites were explained in part by the mixing of DOC and Δ 14C along constant density ( σt) surfaces. However, specific deviations from conservative behavior due to mixing were observed for Δ 14C-DOC at mesopelagic (˜700 m) and near-bottom (˜3600- 3900 m) depths of the continental rise. Comparable findings are reported for DIC, where σt-normalized concentrations and Δ 14C values in Sta. M, rise and upper slope waters were similar, with the exception of slight increases in concentrations and Δ 14C values in near-bottom waters of the rise. These observations indicate that both DOC and DIC in continental rise and slope surface waters of the eastern North Pacific Ocean margin are comprised of a component of actively upwelled material derived

  19. Pu isotopes in the western North Pacific Ocean before the accident at Fukushima Dai-ichi Nuclear Power Station

    Science.gov (United States)

    Yamada, M.; Zheng, J.; Aono, T.

    2011-12-01

    Anthropogenic radionuclides such as Pu-239 (half-life: 24100 yr), Pu-240 (half-life: 6560 yr) and Pu-241 (half-life: 14.325 yr) mainly have been released into the environment as the result of atmospheric nuclear weapons testing. In the North Pacific Ocean, two distinct sources of Pu isotopes can be identified; i.e., the global stratospheric fallout and close-in tropospheric fallout from nuclear weapons testing at the Pacific Proving Grounds in the Marshall Islands. The atom ratio of Pu-240/Pu-239 is a powerful fingerprint to identify the sources of Pu in the ocean. The Pu-240/Pu-239 atom ratios in seawater and marine sediment samples collected in the western North Pacific before the accident at Fukushima Dai-ichi Nuclear Power Station will provide useful background data for understanding the process controlling Pu transport and for distinguishing future Pu sources. The atom ratios of Pu-240/Pu-239 in water columns from the Yamato and Tsushima Basins in the Japan Sea were significantly higher than the mean global fallout ratio of 0.18; however, there were no temporal variation of atom ratios during the period from 1984 to 1993 in the Japan Sea. The total Pu-239+240 inventories in the whole water columns were approximately doubled during the period from 1984 to 1993 in the two basins. The atom ratio of Pu-240/Pu-239 in surface water from Sagami Bay, western North Pacific Ocean, was 0.224 and showed no notable variation from the surface to the bottom with the mean atom ratio being 0.234. The atom ratios for the Pacific coast, near the Rokkasho nuclear fuel reprocessing plant, were approximately the same as the 0.224 ratio obtained from Sagami Bay, western North Pacific margin. The atom ratios in the surficial sediments from Sagami Bay ranged from 0.229 to 0.247. The mean atom ratio in the sediment columns in the East China Sea ranged from 0.248 for the Changjiang estuary to 0.268 for the shelf edge. The observed atom ratios were significantly higher than the mean

  20. A new centennial index to study the Western North Pacific Monsoon decadal variability

    Science.gov (United States)

    Vega, Inmaculada; Gómez-Delgado, F. de Paula; Gallego, David; Ribera, Pedro; Peña-Ortiz, Cristina; García-Herrera, Ricardo

    2016-04-01

    The concept of the Western North Pacific Summer Monsoon (WNPSM) appeared for the first time in 1987. It is, unlike the Indian Summer Monsoon (ISM) and the East Asian summer monsoon (EASM), an oceanic monsoon mostly driven by the meridional gradient of sea surface temperature. Its circulation is characterized by a northwest-southeast oriented monsoon trough with intense precipitation and low-level southwesterlies and upper-tropospheric easterlies in the region [100°-130° E, 5°-15°N]. Up to now, the primary index to characterize the WNPSM has been the Western North Pacific Monsoon Index (WNPMI) which covers the 1949-2013 period. The original WNPMI was defined as the difference of 850-hPa westerlies between two regions: D1 [5°-15°N, 100°-130°E] and D2 [20°-30°N, 110°-140°E]. Both domains are included in the main historical ship routes circumnavigating Asia for hundreds of years. Many of the logbooks of these ships have been preserved in historical archives and they usually contain daily observations of wind force and direction. Therefore, it has been possible to compute a new index of instrumental character, which reconstructs the WNPSM back to the middle of the 19th Century, by using solely historical wind direction records preserved in logbooks. We define the monthly Western North Pacific Directional Index (WNPDI) as the sum of the persistence of the low-level westerly winds in D1 and easterly winds in D2. The advantages of this new index are its nature (instrumental) and its length (1849-2013), which is 100 years longer than the WNPMI (which was based on reanalysis data). Our WNPDI shows a high correlation (r=+0.87, pPhilippines or the west coast of Myanmar where the changes in precipitation between well developed and weak monsoons can reach up to 400 mm. The relationships between the WNPDI and global climatic patterns such as the PDO, the ENSO or El Niño Modoki are extremely complicated and our results suggest that the influence of these patterns is

  1. A relative paleointensity record of the geomagnetic field since 1.6 Ma from the North Pacific

    Science.gov (United States)

    Yamazaki, Toshitsugu; Kanamatsu, Toshiya

    2007-07-01

    A paleomagnetic study was conducted on a sediment core KR0310-PC1 taken from the central North Pacific in order to obtain a relative paleointensity record in the Matuyama chron from this region. The core reached to about 1.6 Ma. The age control is based on the correlation of the S ratio ( S -0.1T) variations with a global oxygen-isotope stack. Isothermal remanent magnetization (IRM) was used as the normalizer of the relative paleointensity estimation; anhysteretic remanent magnetization (ARM) was not adopted because ARM is sensitive to magnetostatic interaction among magnetic particles, which is evidenced in these sediments by an inverse correlation between the ratio of ARM to saturation IRM (SIRM) and SIRM without significant magnetic grain-size changes. For the last 350 kyrs, the record of core NGC65, which was obtained at practically the same site as KR0310-PC1 and covers the Brunhes chron (Yamazaki, 1999), was incorporated because the upper part of KR0310-PC1 was physically disturbed. In the record of NGC65/KR0310-PC1, the average paleointensity in the late Matuyama chron is not lower than that during the Brunhes chron, which does not support the conclusion of Valet et al. (2005) based on their Sint-2000 stack. A spectral analysis on the NGC65/KR0310-PC1 paleointensity record shows a power at the ˜100 kyr eccentricity period. The relative paleointensity and magnetic properties of NGC65/KR0310-PC1 were compared with those of MD982185 from the western equatorial Pacific (Yamazaki and Oda, 2002, 2005). The two sites belong to different oceanographic regimes. Coherent variations in the relative paleointensity despite incoherent changes in the magnetic properties suggest that rock-magnetic contamination to the relative paleointensity is small, if any, and the ˜100 kyr period in the relative paleointensity records would reflect the geomagnetic field behavior.

  2. Interdecadal modulation on the relationship between ENSO and typhoon activity during the late season in the western North Pacific

    Science.gov (United States)

    Zhao, Haikun; Wang, Chunzai

    2016-07-01

    The present study identifies an interdecadal modulation of the Pacific decadal oscillation (PDO) on the relationship between El Niño-Southern oscillation (ENSO) and typhoon activity during the late season (October-December) in the western North Pacific. The PDO is uncorrelated with ENSO during the warm phase of 1979-1997, while the PDO is positively correlated with ENSO during the cold phase of 1998-2012. Further analyses show that the warm phase is associated with the reduced ENSO-typhoon activity relationship and more typhoons, whereas the cold phase is corresponded to the enhanced ENSO-typhoon activity relationship and fewer typhoons. These variations are mainly manifested by a significant difference of typhoon activity in the southeastern part of the western North Pacific. Moreover, the change of ENSO-typhoon relationship is largely due to changes in large-scale environmental conditions especially from low-level vorticity and vertical wind shear between the two phases, which are related to the changes in tropical Indo-Pacific sea surface temperature. The study implies that the phase of the PDO should be taken into account when ENSO is used as a predictor for predicting typhoon activity in the western North Pacific.

  3. Variability in the correlation between Asian dust storms and chlorophyll a concentration from the North to Equatorial Pacific.

    Directory of Open Access Journals (Sweden)

    Sai-Chun Tan

    Full Text Available A long-term record of Asian dust storms showed seven high-occurrence-frequency centers in China. The intrusion of Asian dust into the downwind seas, including the China seas, the Sea of Japan, the subarctic North Pacific, the North Pacific subtropical gyre, and the western and eastern Equatorial Pacific, has been shown to add nutrients to ocean ecosystems and enhance their biological activities. To explore the relationship between the transported dust from various sources to the six seas and oceanic biological activities with different nutrient conditions, the correlation between monthly chlorophyll a concentration in each sea and monthly dust storm occurrence frequencies reaching the sea during 1997-2007 was examined in this study. No correlations were observed between dust and chlorophyll a concentration in the 50 m China seas and the North Pacific subtropical gyre, the correlation coefficients were in the range 0.32-0.57. The correlation coefficients for the western and eastern Equatorial Pacific were relatively low (<0.36. These correlation coefficients were further interpreted in terms of the geographical distributions of dust sources, the transport pathways, the dust deposition, the nutrient conditions of oceans, and the probability of dust storms reaching the seas.

  4. Revised draft: North Central Regional geologic characterization report. Volume 1

    International Nuclear Information System (INIS)

    This report presents available geologic information pertinent to siting a repository for high-level nuclear waste in crystalline rock in Minnesota, Wisconsin, and the Upper Peninsula of Michigan. For each of the states within the North Central Region, information is provided on the disqualifying factor and the screening variables to be used in region-to-area screening. These factors and variables include hydrologically significant natural resources, rock mass extent, post-emplacement faulting, suspected Quaternary faulting, seismicity, rock and mineral resources, major groundwater discharge zones, water resources, groundwater salinity, and state of stress. Information is presented on age, areal extent, shape, thickness of overburden, composition, texture, degree and type of alteration, and structural features associated with each rock body or complex. Regional seismic and tectonic information is presented, including patterns of earthquake occurrence, earthquake magnitudes, horizontal ground accelerations, and vertical crustal movements. Also included are discussions of the rock and mineral deposits or mines located within or near crystalline rock bodies; groundwater resources and regional hydrology; postulated changes in climate and the associated effects; and landforms, surface processes, and surficial materials on or near the subject rock bodies. A discussion of the relationship between the DOE Siting Guidelines and the geologic disqualifying factor and regional screening variables to be used in the region-to-area screening process is also presented

  5. Revised draft: North Central Regional environmental characterization report. Volume 1

    International Nuclear Information System (INIS)

    This report presents available environmental information pertinent to siting a repository for high-level nuclear waste in crystalline rock in Minnesota, Wisconsin, and the Upper Peninsula of Michigan. For each of the states within the North Central Region, information is provided on those environmental disqualifying factors and regional screening variables to be used in region-to-area screening. These environmental factors and variables include existing and proposed federal protected lands, proximity to federal protected lands, existing state protected lands, proximity to state protected lands, population density and distribution, proximity to highly populated areas, national and state forest lands, state wildlife lands, designated critical habitats for threatened and endangered species, surface water bodies, and wetlands. In addition, supplementary descriptive information providing a general characterization of the region is presented, as is information on environmental parameters that may be of use at later phases of screening. Also included is a discussion of the relationship between the DOE Siting Guidelines and those environmental disqualifying factors and regional screening variables to be used in the region-to-area screening process

  6. North Central Regional environmental characterization report. Volume 1. Final report

    International Nuclear Information System (INIS)

    This report presents available environmental information pertinent to siting a repository for high-level nuclear waste in crystalline rock in Minnesota, Wisconsin, and the Upper Peninsula of Michigan. For each of the states within the North Central Region, information is provided on those environmental disqualifying factors and regional screening variables to be used in region-to-area screening. These environmental factors and variables include existing and proposed Federal-protected lands, proximity to Federal-protected lands, components of national forest lands, existing state-protected lands, proximity to state-protected lands, population density and distribution, proximity to highly populated areas or to 1-mile square areas with 1000 or more persons, national and state forest lands, designated critical habitats for threatened and endangered spcies, surface water bodies, and wetlands. In addition, supplementary descriptive information providing a general characterization of the region is presented, as is information on environmental parameters that will be of use at later phases of screening. Also included is a discussion of the relationship between the US Department of Energy Siting Guidelines (10CFR 960) and those environmental disqualifying factors and regional screening variables to be used in the region-to-area screening process

  7. Ground-water resources of north-central Connecticut

    Science.gov (United States)

    Cushman, Robert Vittum

    1964-01-01

    The term 'north-central Connecticut' in this report refers to an area of about 640 square miles within the central lowland of the Connecticut River basin north of Middletown. The area is mostly a broad valley floor underlain by unconsolidated deposits of Pleistocene and Recent age which mantle an erosional surface formed on consolidated rocks of pre-Triassic and Triassic age. The mean annual precipitation at Hartford, near the center of the area, is 42.83 inches and is uniformly distributed throughout the year. The average annual streamflow from the area is about 22 inches or about half the precipitation. The consolidated water-bearing formations are crystalline rocks of pre-Triassic age and sedimentary and igneous rocks of the Newark group of Triassic age. The crystalline rocks include the Middletown gneiss, the Maromas granite gneiss, the Glastonbury granite-gneiss of Rice and Gregory (1906), and the Bolton schist which form the basement complex and the Eastern Upland of north-central Connecticut. Enough water for domestic, stock, and small commercial use generally can be obtained from the crystalline rocks. Recoverable ground water occurs in the interconnected joints and fracture zones and is yielded in amounts ranging from 29 to 35 gpm (gallons per minute) to wells ranging in depth from 29 to 550 feet. The sedimentary rocks of Triassic age underlie all the Connecticut River Lowland and are predominantly arkosic sandstone and shale. Water supplies sufficient for domestic, stock, and small commercial use can be obtained from shallow wells penetrating these rocks, and larger supplies sufficient for industries and smaller municipalities can probably be obtained from deeper wells. Reported yields range from ? to 578 gpm; the larger yields are generally obtained from wells between 300 and 600 feet in depth. Yields are larger where the overlying material is sand and gravel or where the rocks are well fractured. The igneous rocks of Triassic age are basalt and have

  8. NDT education improvements through the North Central Collaboration for NDT

    Science.gov (United States)

    Larson, B. F.; Wormley, S. J.

    2001-04-01

    The North Central Collaboration for Education in NDE/NDT is an effort aimed at enhancing NDE education and improving articulation between community college technician programs and university technical degree programs. NDT instructors at four community colleges are working with the staff at the Center for NDE at Iowa State University. Through this arrangement, advanced teaching methods and new materials that allow students to learn concepts better and in less time are being developed. For example, materials have been developed that will facilitate the use of an X-ray inspection simulation program in teaching basic radiography. Course materials have been developed and posted on the Internet that allow instructors to use interactive Java applets to better illustrate and explain difficult to grasp concepts. Some of the materials introduce subjects that are not currently extensively taught such as real-time radiography and distance-amplitude-correction (DAC) through curved surfaces. This paper will review NDT technician education, discuss the need for improvement in the methods used to educate technicians and highlight some of the efforts of the collaboration.

  9. North Central Regional geologic characterization report. Volume 1. Final report

    International Nuclear Information System (INIS)

    This report presents available geologic information pertinent to siting a repository for high-level nuclear waste in crystalline rock in Minnesota, Wisconsin, and the Upper Peninsula of Michigan. For each of the states within the North Central Region, information is provided on the geologic disqualifying factor and the geologic regional screening variables to be used in region-to-area screening. The geologic factor and variables include deep mines and quarries, rock mass extent, post-emplacement faulting, suspected Quaternary faulting, seismicity, rock and mineral resources, major groundwater discharge zones, groundwater resources, state of stress, thickness of rock mass, and thickness of overburden. Information is presented on age, areal extent, shape, composition, texture, degree and type of alteration, thickness, and structural features associated with each rock body or complex. Regional seismic and tectonic information is presented, including patterns of earthquake occurrence, earthquake magnitudes, horizontal ground accelerations, and vertical crustal movements. Also included are discussions of the rock and mineral deposits or mines located within or near crystalline rock bodies; groundwater resources and regional hydrology; postulated changes in climate and the associated effects; and landforms, surface processes, and surficial materials on or near the rock bodies. A discussion is also presented of the relationship between the US Department of Energy Siting Guidelines (10 CFR 960) and the geologic disqualifying factor and regional screening variables to be used in the region-to-area screening process. 43 figs., 15 tabs

  10. The Coupled Model Predictability of the Western North Pacific Summer Monsoon with Different Leading Times

    Institute of Scientific and Technical Information of China (English)

    LU Ri-Yu; LI Chao-Fan; Se-Hwan YANG; Buwen DONG

    2012-01-01

    Leading time length is an important issue for modeling seasonal forecasts. In this study, a comparison of the interannual predictability of the Western North Pacific (WNP) summer monsoon between different leading months was performed by using one-, four-, and sevenmonth lead retrospective forecasts (hindcasts) of four coupled models from Ensembles-Based Predictions of Climate Changes and Their Impacts (ENSEMBLES) for the period of 1960 2005. It is found that the WNP summer anomalies, including lower-tropospheric circulation and precipitation anomalies, can be well predicted for all these leading months. The accuracy of the four-month lead prediction is only slightly weaker than that of the one-month lead prediction, although the skill decreases with the increase of leading months.

  11. 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.

    2015-12-01

    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 δ13C 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.

  12. Enhanced or Weakened Western North Pacific Subtropical High under Global Warming?

    Science.gov (United States)

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

    2015-11-26

    The Western North Pacific Subtropical High (WNPSH) regulates East Asian climate in summer. Anomalous WNPSH causes floods, droughts and heat waves in China, Japan and Korea. The potential change of the WNPSH under global warming is concerned by Asian people, but whether the WNPSH would be enhanced or weakened remains inconclusive. Based on the multi-model climate change projection from the 5th phase of Coupled Model Intercomparison Project (CMIP5), we show evidences that the WNPSH tends to weaken and retreat eastward in the mid-troposphere in response to global warming, accompanied by an eastward expansion of East Asian rain belt along the northwestern flank of WNPSH. Weakened meridional temperature gradient on the northern flank of WNPSH and the associated thermal wind account for the weakened WNPSH in the mid troposphere. We recommend the WNPSH be measured by eddy geopotential height (He) instead of traditionally used geopotential height, especially in climate change studies.

  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.

  14. Intermediate-wavelength magnetic anomaly field of the North Pacific and posible source distributions

    Science.gov (United States)

    Labrecque, J. L.; Cande, S. C.; Jarrard, R. D.

    1985-01-01

    A technique that eliminates external field sources and the effects of strike aliasing was used to extract from marine survey data the intermediate wavelength magnetic anomaly field for (B) in the North Pacific. A strong correlation exists between this field and the Magsat field although a directional sensitivity in the Magsat field can be detected. The intermediate wavelength field is correlated to tectonic features. Island arcs appear as positive anomalies of induced origin likely due to variations in crustal thickness. Seamount chains and oceanic plateaus also are manifested by strong anomalies. The primary contribution to many of these anomalies appears to be due to a remanent magnetization. The source parameters for the remainder of these features are presently unidentified ambiguous. Results indicate that the sea surface field is a valuable source of information for secular variation analysis and the resolution of intermediate wavelength source parameters.

  15. The intermediate wavelength magnetic anomaly field of the north Pacific and possible source distributions

    Science.gov (United States)

    Labrecque, J. L.; Cande, S. C.; Jarrard, R. D. (Principal Investigator)

    1983-01-01

    A technique that eliminates external field sources and the effects of strike aliasing was used to extract from marine survey data the intermediate wavelength magnetic anomaly field for (B) in the North Pacific. A strong correlation exists between this field and the MAGSAT field although a directional sensitivity in the MAGSAT field can be detected. The intermediate wavelength field is correlated to tectonic features. Island arcs appear as positive anomalies of induced origin likely due to variations in crustal thickness. Seamount chains and oceanic plateaus also are manifested by strong anomalies. The primary contribution to many of these anomalies appears to be due to a remanent magnetization. The source parameters for the remainder of these features are presently unidentified ambiguous. Results indicate that the sea surface field is a valuable source of information for secular variation analysis and the resolution of intermediate wavelength source parameters.

  16. 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. PMID:26612834

  17. Asian industrial lead inputs to the North Pacific evidenced by lead concentrations and isotopic compositions in surface waters and aerosols.

    Science.gov (United States)

    Gallon, Céline; Ranville, Mara A; Conaway, Christopher H; Landing, William M; Buck, Clifton S; Morton, Peter L; Flegal, A Russell

    2011-12-01

    Recent trends of atmospheric lead deposition to the North Pacific were investigated with analyses of lead in aerosols and surface waters collected on the fourth Intergovernmental Oceanographic Commission Contaminant Baseline Survey from May to June, 2002. Lead concentrations of the aerosols varied by 2 orders of magnitude (0.1-26.4 pmol/m(3)) due in part to variations in dust deposition during the cruise. The ranges in lead aerosol enrichment factors relative to iron (1-119) and aluminum (3-168) were similar, evidencing the transport of Asian industrial lead aerosols across the North Pacific. The oceanic deposition of some of those aerosols was substantiated by the gradient of lead concentrations of North Pacific waters, which varied 3-fold (32.7-103.5 pmol/kg), were highest along with the Asian margin of the basin, and decreased eastward. The hypothesized predominance of Asian industrial lead inputs to the North Pacific was further corroborated by the lead isotopic composition of ocean surface waters ((206)Pb/(207)Pb = 1.157-1.169; (208)Pb/(206)Pb = 2.093-2.118), which fell within the range of isotopic ratios reported in Asian aerosols that are primarily attributed to Chinese industrial lead emissions.

  18. Pre-bomb marine reservoir ages in the western north Pacific : Preliminary result on Kyoto University collection

    NARCIS (Netherlands)

    Yoneda, M; Kitagawa, H; van der Plicht, J; Uchida, M; Tanaka, A; Uehiro, T; Shibata, Y; Morita, M; Ohno, T

    2000-01-01

    The calibration of radiocarbon dates on marine materials involves a global marine calibration with regional corrections. The marine reservoir ages in the Western North Pacific have not been discussed, while it is quite important to determine the timing of palaeo-environmental changes as well as arch

  19. Effects of South China Sea/western North Pacific summer monsoon on tropospheric biennial oscillation (TBO)

    Institute of Scientific and Technical Information of China (English)

    Zheng Bin; Gu De-Jun; Lin Ai-Lan; Li Chun-Hui

    2007-01-01

    Severed theories have been developed to explain tropical biennial oscillation (TBO), as an air-sea interactive system to impact Asian and global weather and climate, and some models have been established to produce a TBO. A simple 5-box model, with almost all the key processes associated with TBO, can produce a TBO by including air-sea interactions in the monsoon regions. Despite that, the South China Sea/western North Pacific summer monsoon (SCS/WNPSM), a very important monsoon subsystem, is neglected. In this paper, based on the dynamical framework of 5-box model, the term of SCS/WNPSM has been added and a 6-box model has been developed. Comparing the difference of TBO sensibilities with several key parameters, air-sea coupling coefficient α, SST-thermocline feedback coefficient γ and wind-evaporation feedback coefficient λ, between the modified model and original model, TBO is more sensible to the parameters in the new model. The results imply that the eastern Pacific and local wind-evaporation play more important roles in the TBO when including SCS/WNPSM.

  20. Observed Eastward Progression of the Fukushima 134Cs Signal Across the North Pacific

    Science.gov (United States)

    Yoshida, S.; Macdonald, A. M.; Jayne, S. R.; Rypina, I.; Buesseler, K.

    2015-12-01

    Radionuclide samples taken as part of hydrographic surveys at 30°N in the North Pacific reveal that the easternmost edge of Fukushima-derived 134Cs observed at 174.3°W in 2012 had progressed eastward across the basin to 160.6°W by 2013. The 2013 30°N observations indicate surface 134Cs concentrations of 3-5 Bq/m3 between 160°E and 160°W, slightly lower concentrations west of 160°E and no detectable signal east of 160.6°W. Profile samples show 134Cs penetration to 500 m west of 180° with shoaling penetration depth toward to the east. The near-uniform vertical distribution of 137Cs between 152°W and 121.3°W in the top 500 m is indicative of trace amounts of radionuclides remaining from weapons testing. The physical processes responsible for the deep 134Cs penetration in the western Pacific appear to be related to distinct water mass subduction pathways, however the timing and rapidity of deep penetration over the broad scales observed has yet to be clarified.

  1. Biological communities in San Francisco Bay track large-scale climate forcing over the North Pacific

    Science.gov (United States)

    Cloern, James E.; Hieb, Kathryn A.; Jacobson, Teresa; Sansó, Bruno; Di Lorenzo, Emanuele; Stacey, Mark T.; Largier, John L.; Meiring, Wendy; Peterson, William T.; Powell, Thomas M.; Winder, Monika; Jassby, Alan D.

    2010-11-01

    Long-term observations show that fish and plankton populations in the ocean fluctuate in synchrony with large-scale climate patterns, but similar evidence is lacking for estuaries because of shorter observational records. Marine fish and invertebrates have been sampled in San Francisco Bay since 1980 and exhibit large, unexplained population changes including record-high abundances of common species after 1999. Our analysis shows that populations of demersal fish, crabs and shrimp covary with the Pacific Decadal Oscillation (PDO) and North Pacific Gyre Oscillation (NPGO), both of which reversed signs in 1999. A time series model forced by the atmospheric driver of NPGO accounts for two-thirds of the variability in the first principal component of species abundances, and generalized linear models forced by PDO and NPGO account for most of the annual variability of individual species. We infer that synchronous shifts in climate patterns and community variability in San Francisco Bay are related to changes in oceanic wind forcing that modify coastal currents, upwelling intensity, surface temperature, and their influence on recruitment of marine species that utilize estuaries as nursery habitat. Ecological forecasts of estuarine responses to climate change must therefore consider how altered patterns of atmospheric forcing across ocean basins influence coastal oceanography as well as watershed hydrology.

  2. THE EFFECT OF WARM POOL THERMAL STATES ON TROPICAL CYCLONES IN THE WESTERN NORTH PACIFIC

    Institute of Scientific and Technical Information of China (English)

    CHEN Guang-hua; HUANG Rong-hui

    2007-01-01

    The influence of thermal states in the warm pool on tropical cyclones (TCs) in the western North Pacific (WNP) is investigated. There are fewer typhoons during warm years of the warm pool in which tropical storms tend to form in the northwest quadrant and move westward. Inversely, typhoons tend to recurve northeastward to the southeast of Japan and increase in number in the southeast quadrant during cold years. Based on composite analyses, circulation-induced dynamic factors rather than thermal factors are identified as being responsible for TCs activities. During the warm state, the monsoon trough retreats westwards, which leads to anomalous vorticity in low-level and divergence in high-level in the western part of west Pacific. Above-normal TCs activity is found in this area. Furthermore, wind anomalies at 500 hPa determine the main track types. On the contrary, when the warm pool is in cold state, the atmospheric circulation is responsible for the formation of more TCs in the southeast quadrant and recurving track.

  3. Response to state comments on the revised draft North Central Regional characterization reports for the Crystalline Repository Project

    International Nuclear Information System (INIS)

    The purpose of this document is to respond to the comments received from the states of the North Central Region on the revised draft North Central Regional Characterization Reports (RCRs). The responses in this document indicate the manner in which the suggestions or comments received have been considered in modifying the revised draft North Central RCRs. Both general comments related to the overall Crystalline Repository Project (CRP) and comments on specific sections of the RCRs are addressed. This document responds to North Central State comments on both the revised draft North Central Regional Geologic Characterization Report (RGCR) and the revised draft North Central Regional Environmental Characterization Report (RECR)

  4. Resource manager information needs regarding hydrologic regime shifts for the North Pacific Landscape Conservation

    Science.gov (United States)

    Woodward, Andrea; Jenni, Karen

    2014-01-01

    Landscape Conservation Cooperatives (LCCs) are a network of 22 public-private partnerships, defined by ecoregion, that share and provide science to ensure the sustainability of land, water, wildlife, and cultural resources in North America. LCCs were established by the U.S. Department of the Interior (DOI) in recognition of the fact that response to climate change must be coordinated on a landscape-level basis because important resources, ecosystem processes, and resource management challenges extend beyond most of the boundaries considered in current natural resource management. The North Pacific LCC (NPLCC) covers the range of the Pacific coastal temperate rainforest, including an area of 528,360 km2 spanning 22 degrees of latitude from the Kenai Peninsula, Alaska, to Bodega Bay, California. The coverage area includes parts of four States, two Canadian provinces, and more than 100 Tribes and First Nation language groups. It extends from alpine areas at the crest of coastal mountains across subalpine, montane, and lowland forests to the nearshore marine environment. This wide range of latitudes and elevation zones; terrestrial, freshwater, and marine habitats; and complex jurisdictional boundaries hosts a diversity of natural resources and their corresponding management issues are equally diverse. As evidenced by the Science and Traditional Ecological Knowledge (S-TEK) Strategy guiding principles, identifying and responding to the needs of resource managers is key to the success of the NPLCC. To help achieve this goal of the NPLCC, the U.S. Geological Survey (USGS) has organized several workshops with resource managers and resource scientists to identify management information needs relevant to the priority topics identified in the S-TEK Strategy. Here, we detail the results from a first workshop to address the effects of changes in hydrologic regime on rivers, streams, and riparian corridors. The workshop focused on a subset of the full NPLCC geography and was

  5. Arabian Peninsula-North Pacific Oscillation and its association with the Asian summer monsoon

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Using correlation and EOF analyses on sea level pressure from 57-year NCEP-NCAR reanalysis data, the Arabian Peninsula-North Pacific Oscillation (APNPO) is identified. The APNPO reflects the co-variability between the North Pacific high and South Asian summer monsoon low. This teleconnec- tion pattern is closely related to the Asian summer monsoon. On interannual timescale, it co-varies with both the East Asian summer monsoon (EASM) and South Asian summer monsoon (SASM); on decadal timescale, it co-varies with the EASM: both exhibit two abrupt climate changes in the middle 1960s and the late 1970s respectively. The possible physical process for the connections between the APNPO and Asian summer monsoon is then explored by analyzing the APNPO-related atmospheric circulations. The results show that with a strong APNPO, the Somali Jet, SASM flow, EASM flow, and South Asian high are all enhanced, and an anomalous anticyclone is produced at the upper level over northeast China via a zonal wave train. Meanwhile, the moisture transportation to the Asian monsoon regions is also strengthened in a strong APNPO year, leading to a strong moisture convergence over India and northern China. All these changes of circulations and moisture conditions finally result in an anoma- lous Asian summer monsoon and monsoon rainfall over India and northern China. In addition, the APNPO has a good persistence from spring to summer. The spring APNPO is also significantly corre- lated with Asian summer monsoon variability. The spring APNPO might therefore provide valuable in- formation for the prediction of Asian summer monsoon.

  6. Ocean acidification from 1997 to 2011 in the subarctic western North Pacific Ocean

    Directory of Open Access Journals (Sweden)

    M. Wakita

    2013-05-01

    Full Text Available Rising atmospheric CO2 contents have led to greater CO2 uptake by the oceans, lowering both pH due to increasing hydrogen ions and CaCO3 saturation states due to declining carbonate ion (CO32−. Here, we used previously compiled data sets and new data collected in 2010 and 2011 to investigate ocean acidification of the North Pacific western subarctic gyre. In winter, the western subarctic gyre is a source of CO2 to the atmosphere because of convective mixing of deep waters rich in dissolved inorganic carbon (DIC. We calculated pH in winter mixed layer from DIC and total alkalinity (TA, and found that it decreased at the rate of −0.001 ± 0.0004 yr−1 from 1997 to 2011. This decrease rate is slower than that expected under condition of seawater/atmosphere equilibration, and it is also slower than the rate in the subtropical regions (−0.002 yr−1. The slow rate is caused by a reduction of CO2 emission in winter due to an increase in TA. Below the mixed layer, the calcite saturation horizon (~185 m depth shoaled at the rate of 2.9 ± 0.9 m yr−1 as the result of the declining CO32− concentration (−0.03 ± 0.01 μmol k−1yr−1. Between 200 m and 300 m depth, pH decline during the study period (−0.0051 ± 0.0010 yr−1 was larger than ever reported in the open North Pacific. This enhanced acidification rate below the calcite saturation horizon reflected not only the uptake of anthropogenic CO2 but also the increase in the decomposition of organic matter evaluated from the increase in AOU, which suggests that the dissolution of CaCO3 particles increased.

  7. Wind-driven circulation in the subarctic north Pacific using altimeter data

    Indian Academy of Sciences (India)

    Osamu Isoguchi; Hiroshi Kawamura

    2002-09-01

    Time-dependent wind-driven circulation in the subarctic north Pacific is investigated by using Topex/Poseidon (T/P) altimeter data and European Centre for Medium-Range Weather Forecasts (ECMWF) wind data for about 6 years. The first empirical orthogonal function (EOF) of the T/P- derived sea level anomaly (SLA) without the variation related to the steric height change (SLA1) and the first EOF of the ECMWF-based wind stress curl fields represent basin-sized south-north oscillations and their time series agree well with a correlation of 0.49. They appear to express the spin-up and spin-down of the subarctic gyre. The third EOF of SLA (SLA3) and the second EOF of the wind stress curl are also related to the variation of the subarctic gyre. Though the correlation of their time series is 0.27, drastic changes in early winter coincide well. The two EOF pairs can be considered to mean that the SLA variation followed by the latitudinal migration of the Aleutian low is separated into two standing oscillation patterns, that is, the sea level variation combined with SLA1 and SLA3 expresses seasonal variations of the wind-driven circulation of the subarctic gyre. The interannual SLAs constructed by subtracting the SLA1 and SLA3 components clearly show trans-pacific westward propagation even in the high-latitudes. The time series of SLA1 is in agreement with that of in situ SLAs measured with the tide gauge at Petropavlovsk (53-01N, 158-38E), which implies the possibility to monitor the subarctic circulation using tide gauge data.

  8. Two new species of the bee genus Peponapis, with a key to the North and Central American species (Hymenoptera: Apidae: Eucerini) Dos especies nuevas de abejas del género Peponapis, con una clave para las especies de América del Norte y Central (Hymenoptera: Apidae: Eucerini)

    OpenAIRE

    Ricardo Ayala; Terry Griswold

    2012-01-01

    Two new species of squash bees, Peponapis pacifica Ayala and Griswold sp. n. and P. parkeri Griswold and Ayala sp. n., are described and illustrated. Peponapis pacifica is oligolectic on flowers of Schizocarpum longisepalum (Cucurbitaceae) endemic to Mexico, where it is found in the tropical dry forest along the Pacific Coast, between Sonora and Chiapas and in the Balsas River basin; and P. parkeri is known only from the Pacific slope of Costa Rica. A key for the North and Central American sp...

  9. Skill of western North Pacific tropical cyclone intensity forecast guidance relative to Weighted-Analog technique

    Science.gov (United States)

    Tsai, Hsiao-Chung; Elsberry, Russell L.

    2016-06-01

    The accuracy of the western North Pacific tropical cyclone intensity forecast guidance products available at the Joint Typhoon Warning Center (JTWC) is evaluated relative to a new skill metric called Weighted Analog Intensity Pacific (WAIP) that includes knowledge of the JTWC official track forecast and the current intensity, which is information that is available at the time the intensity forecast is generated. An intensity consensus technique called S5XX that includes statistical-dynamic intensity forecasts plus other dynamic and thermodynamic prediction techniques has statistically significant smaller errors than WAIP at 24 h and 48 h and has similar accuracy through 120 h. While the track consensus CONW is a critical input to the JTWC official track forecast, it has no skill relative to WAIP as an intensity forecast. Three regional numerical models also have no skill relative to WAIP, and especially at forecast intervals beyond 72 h because their mean absolute errors are statistically significantly larger than for WAIP. Furthermore, these regional models have statistically significant positive or negative intensity biases relative to the verifying intensities. However, an experimental consensus technique called CMES that includes these three regional models has small accuracy relative to WAIP in the 24 h to 72 h forecast intervals. Geographical-based comparisons of the intensity guidance products with the WAIP indicate almost all of the products are more accurate than WAIP over the South China Sea region. The statistical-dynamic consensus technique S5XX does have skill through 72 h for landfalling situations along the coasts of China and Southeast Asia. At 120 h, the WAIP has superior performance over the guidance products over most areas of the western North Pacific, but again the S5XX is more accurate than WAIP for landfalling tropical cyclones on the Philippine Islands, Southeast Asia, South China, and northeastern Japan. This information will be useful to

  10. Distribution, source and chemical speciation of phosphorus in surface sediments of the central Pacific Ocean

    Science.gov (United States)

    Ni, Jianyu; Lin, Peng; Zhen, Yang; Yao, Xuying; Guo, Laodong

    2015-11-01

    The abundance of five forms of phosphorus (P) in surface sediments from the central Pacific Ocean (4.5-15ºN, 154-143ºW) was determined using a sequential extraction procedure (SEDEX) to examine the distribution and source of different P species. Total P (TP) concentrations ranged from 13.2 to 119 μmol-P/g with an average of 48.6±27.4 μmol-P/g. Within the TP pool, total inorganic P (TIP) concentrations varied from 11.1 to 121 μmol-P/g, while total organic P (TOP) concentrations ranged from undetectable to 4.8 μmol-P/g. Inorganic P was generally the predominant form in surface sediments, comprising on average up to 93% of sedimentary TP, leaving <16% as TOP. Among the five P species, the authigenic or CaCO3-bound P and detrital P were the two major P species (comprising on average 43.4±13.5% and 45.7±14.8% of TP, respectively), followed by the refractory organic P, representing 6.7±2.4% of TP. Fe-bound P accounted for 3.3±1.3% of TP, and exchangeable or adsorbed P made up less than 1% of TP. The spatial distribution of different sedimentary P species showed that higher concentrations of detrital P and Fe-bound P were both found at around 11°N, suggesting similar sources for these two P species. Much of the detrital P was derived from atmospheric sources in the study area, where heavy rainfall in the intertropical convergence zone between 3°N and 11°N has been widely reported. Compared with other marine environments, the central Pacific Ocean had relatively higher detrital P, but lower abundance of adsorbed-P and Fe-bound P. These unquine results suggested that most of the labile P could have been released into the water column during its settling from the surface to the seafloor, or that atmospheric inputs of refractory P were an important source for sedimentary P, accounting for an average of 63% of the TP, in the central Pacific Ocean. High proportions of authigenic P in deep-sea sediments, on the other hand, implied that oceanic sediments are an

  11. Climate variation and prediction of rapid intensification in tropical cyclones in the western North Pacific

    Science.gov (United States)

    Wang, B.; Zhou, X.

    2008-02-01

    One of the greatest challenges in tropical weather forecasting is the rapid intensification (RI) of the tropical cyclone (TC), during which its one-minute maximum sustained wind speed increases at least 30 knots per 24 hours. Here we identify and elucidate the climatic conditions that are critical to the frequency and location of the RI on annual, intraseasonal, and interannual time scales. Whereas RI and formation share common environmental preferences, we found that the percentage of TCs with RI varies annually and from year to year. In August, only 30% of TC actually experiences RI, in contrast to the annual maximum of 47% in November. The proportion of RI in July September is higher during El Niño years (53%) than the corresponding one in the La Niña years (37%). Three climate factors may contribute to the increase in the proportion of RI: the southward shift in the monthly or seasonal mean location of the TC formation, the increase in the low-level westerly meridional shear vorticity, and the decrease in northerly vertical shear. When the mean latitude of TC formation increases, the mixed-layer heat content decreases while TC’s inertial stability increases; both are more detrimental to the RI than to TC formation because the RI requires large amount of latent heat energy being extracted efficiently from the ocean mixed layer and requires accelerated low-level radial inflow that carries latent heat reaching the inner core region. We further demonstrate that the RI frequency in the Philippine Sea and South China Sea can be predicted 10 to 30 days in advance based on the convective anomalies in the equatorial western Pacific (5° S 5° N, 130° 150° E) on intraseasonal time scale. The Niño 3.4 SSTA in June is a potential predictor for the peak TC season (July September) RI activity in the southeast quadrant of the western North Pacific (0 20° N, 140 180° E). The RI is an essential characteristic of category 4 and 5 hurricanes and super typhoons because

  12. Relationships among aerosol constituents from Asia and the North Pacific during PEM-West A

    Science.gov (United States)

    Arimoto, R.; Duce, R. A.; Savoie, D. L.; Prospero, J. M.; Talbot, R.; Cullen, J. D.; Tomza, U.; Lewis, N. F.; Ray, B. J.

    1996-01-01

    Aerosol particle samples collected from Asia and the North Pacific were analyzed to investigate the relationships among atmospheric sea salt, mineral aerosol, biogenic emissions (methanesulfonate (MSA)), and several anthropogenic substances (sulfate, nitrate, and various trace elements). These studies specifically focused on the sources for aerosol SO4= and on the long-range transport of continental materials to the North Pacific. Ground-based aerosol sampling was conducted at four coastal-continental sites: Hong Kong, Taiwan, Okinawa, and Cheju; and at three remote Pacific islands, Shemya, Midway, and Oahu. Non-sea-salt (nss) SO4= and MSA were uncorrelated at the East Asian sites presumably because pollution sources overwhelm the biogenic emissions of nss SO4=. At the coastal-continental sites, marine biogenic emissions accounted for only 10 to Midway r = 0.70; Oahu r = 0.59), and higher percentages of biogenic nss SO4= occurred, 55 and 70% at Oahu and Midway, respectively. The concentrations of nss SO4= and NO3- were correlated at Cheju, Hong Kong, Taiwan, Okinawa, Midway, and Oahu, indicating some similarities in their sources and the processes governing their transport; however, differences in the nss SO4=/NO3- ratios among sites suggest regional differences in the pollution component of the aerosol. At Shemya the concentrations of MSA during the summer (100 ng m-3 or more) are about 2 orders of magnitude higher than those in winter. The dimethylsulfide-derived fraction of the nss SO4= is highest in the summer when the monthly median nss SO4=/MSA ratios range from 2.7 to 4.5, i.e., comparable to the ratios observed over Antarctica and other high-latitude locations. However, the monthly median nss SO4=/MSA ratios increase, reaching 50 to 200 in the winter as productivity nearly ceases, and the biogenic fraction of nss SO4= at Shemya decreases dramatically; this suggests a strong seasonal pollution component to the sulfate aerosol. The meteorological conditions

  13. Stable isotope signatures of seasonal precipitation on the Pacific coast of central Panama.

    Science.gov (United States)

    Kern, Zoltán; Harmon, Russell S; Fórizs, István

    2016-01-01

    As calculated from data archived in the IAEA-WMO Global Network of Isotopes in Precipitation programme, the amount-weighted local meteoric water line for the Pacific coast of central Panama is: δ(2)H = 7.63(±0.08) × δ(18)O + 6.51(±0.49). Amount-weighted mean isotopic values were regressed against the sea surface temperature (SST) fields of the adjacent tropical oceans. A negative correlation of precipitation isotope composition with Caribbean SSTs is observed only for the early wet season (May-June), whilst the mid-summer dry period is characterized by positive correlation with eastern Pacific SSTs, similar to the late wet season (October-November). The negative response of May-June rainfall isotopic composition to Caribbean SSTs is explained by a SST-mediated change in stratiform rain fraction from organized convective systems proximal to the Inter Tropical Convergence Zone (ITCZ). The positive correlation for the rest of the wet season, when the organized convective zone of ITCZ and its attached stratiform belt are distant from the Pacific coast of Panama, is interpreted as simple evaporative temperature effect on isotopic fractionation. PMID:25761056

  14. Assimilation of Satellite Altimetry into a Western North Pacific Operational Model

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    An ocean data assimilation system, COMPASS-K (the Comprehensive Ocean Modeling, Prediction, Analysis and Synthesis System in the Kuroshio-region), has been developed at the Meteorological Research Institute (MRI). The purposes of the development are understanding ocean variability in the Kuroshio re gion as a local response to a global climate change with assimilated four-dimensional data sets, develop ment of an operational system in the Japan Meteorological Agency, and for the GODAE (Global Ocean Data Assimilation Experiment) project. The model is an eddy permitting version of an MRI-OGCM. Space-time decorrelation scales of ocean variability are estimated with TOPEX/POSEIDON (T/P) altimeter data. Subsurface temperature and salinity fields are projected from the T / P altimeter data with a statistical correlation method and are assim ilated into the model with a time-retrospective nudging scheme. Seasonal variation in the western North Pacific is investigated. Realistic space-time distribution of the physical quantities, the path of Kuroshio and its separation from Honshu are captured well. The Kuroshio volume transport is well reproduced in a reanalysis experiment of 1993. Preliminary predictability experi ments are done in February and March, 1994. Predictability diagram shows the time scale of the predictability for temperature field is about 17 days in the Kuroshio south of Japan. This time scale is smal ler than that in the North Atlantic.

  15. Magnetotelluric Data, North Central Yucca Flat, Nevada Test Site, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    J.M. Williams; B.D. Rodriguez, and T.H. Asch

    2005-11-23

    Nuclear weapons are integral to the defense of the United States. The U.S. Department of Energy, as the steward of these devices, must continue to gauge the efficacy of the individual weapons. This could be accomplished by occasional testing at the Nevada Test Site (NTS) in Nevada, northwest of Las Vegas. Yucca Flat Basin is one of the testing areas at the NTS. One issue of concern is the nature of the somewhat poorly constrained pre-Tertiary geology and its effects on ground-water flow in the area subsequent to a nuclear test. Ground-water modelers would like to know more about the hydrostratigraphy and geologic structure to support a hydrostratigraphic framework model that is under development for the Yucca Flat Corrective Action Unit (CAU). During 2003, the U.S. Geological Survey (USGS) collected and processed Magnetotelluric (MT) and Audio-magnetotelluric (AMT) data at the Nevada Test Site in and near Yucca Flat to help characterize this pre-Tertiary geology. That work will help to define the character, thickness, and lateral extent of pre-Tertiary confining units. In particular, a major goal has been to define the upper clastic confining unit (UCCU) in the Yucca Flat area. Interpretation will include a three-dimensional (3-D) character analysis and two-dimensional (2-D) resistivity model. The purpose of this report is to release the MT sounding data for north central Yucca Flat, Profile 7, as shown in Figure 1. No interpretation of the data is included here.

  16. Neogene north American-Caribbean plate boundary across Northern Central America: Offset along the polochic fault

    Science.gov (United States)

    Burkart, Burke

    1983-12-01

    The Polochic fault was a segment of the North American-Caribbean plate boundary across Central America in the Neogene. Its 130 km of left slip was previously determined by matching structures and stratigraphie outcrop patterns of northwest and central Guatemala across the fault. Additional support for the model and the youthfulness of the recorded offset comes from an essentially perfect match of major geomorphic features across the fault. A reconstruction process which eliminates 123 km of left slip brings together rivers and drainage divides that existed before the Polochic became active. With the reconstruction carried across the isthmus on an east-west fault the regional structural geology assumes the coherent pattern of a continuous orogenic belt whose geometry is compatible with the model of collisional tectonics centered on the Motagua "suture zone". Confined within this belt, narrowed to some 60 km by the reconstruction, lie the major Laramide thrusts, folds and tectonically emplaced serpentinites of Guatemala. Crystalline rocks of Guatemala re-join the Chiapas Massif and Paleozoic sedimentary rocks, exposed in the core of an almost-continuous anticlinorium, extend from southern Chiapas to Lake Izabal. The Polochic does not bend in eastern Guatemala but continues eastward to the Motagua fault where it dies. Westward drift of the northern block resulted in rifting which extended from eastern Guatemala into the Caribbean along the Cayman trough. The Honduras depression may represent an element of a triple junction along with the Polochic and Izabal-Cayman rift. The Polochic continues westward into the Pacific Ocean and offsets the Middle America trench. The Polochic has offset the Miocene volcanic belt of northern Central America, confirming the previous estimate of a Neogene time of movement. About 300 km of relative east-west Neogene displacement has been recorded on the Mid-Cayman rise, only 130 km of which can be accounted for across the Polochic. It is

  17. Impacts of enhanced central Pacific ENSO on wave climate and headland-bay beach morphology

    Science.gov (United States)

    Mortlock, Thomas R.; Goodwin, Ian D.

    2016-06-01

    Wave climate and Pacific basin coastal behaviour associated with El Niño Southern Oscillation (ENSO) is understood at a reconnaissance level, but the coastal response to different central Pacific (CP) versus eastern Pacific (EP) flavours of ENSO is unknown. We show that CP ENSO events produce different patterns of directional wave power to EP ENSO along the southeast Australian shelf and southwest Pacific region, because of significant variability in trade-wind wave generation. The modulation of the trade wind wave climate during CP ENSO has thus far been neglected in existing coastal process studies. We also show that coastal change between CP and EP ENSO cannot be inferred from shifts in the deepwater wave climate. This is because variability in trade wind wave generation is masked in deepwater by the persistence of high power extra-tropical waves that have reduced impact on nearshore processes due to high wave refraction. Morphodynamic modelling in a headland-bay beach indicates that CP ENSO leads to higher coastal erosion potential and slower post-storm recovery than EP ENSO during an El Niño/La Niña cycle. We show that the alongshore variability in beach morphological type can be used to model the static equilibrium planform response for each ENSO phase. Results indicate that shoreline response to ENSO in most headland-bay beach coasts is not as simple as the existing paradigm that (anti-) clockwise rotation occurs during El Niño (La Niña). Our methods provide a second-order approach to project coastal response and predict the discrete shoreline rotations for ENSO flavours.

  18. Convergent evolution of ecomorphological adaptations in geographically isolated Bay gobies (Teleostei: Gobionellidae) of the temperate North Pacific.

    Science.gov (United States)

    Ellingson, Ryan A; Swift, Camm C; Findley, Lloyd T; Jacobs, David K

    2014-01-01

    North Pacific Bay gobies (Teleostei: Gobioidei: Gobionellidae) inhabit bays, beaches, coastal lagoons, and estuaries of temperate Asia and North America, but are absent from the boreal northernmost Pacific. Previously, morphological characters conventionally subdivided the clade into two groups - an elongate-bodied, infaunal-inhabiting "Astrabe" group, and a deeper-bodied, non-infaunal "Chasmichthys" group - each with a disjunct East-West (amphi-) Pacific distribution. Here we use mitochondrial and multi-locus nuclear DNA sequence data to show that several morphological characters previously used to delimit these two groups have in fact arisen independently on both sides of the Pacific, revealing convergence of ecologically adaptive characters within a geographically divided clade. Basal divergence of the resultant tree coincides with a dramatic global cooling event at the Eocene/Oligocene transition, without evidence of subsequent trans-Pacific migration. A novel approach to partitioning sequence data by relative rate, as opposed to traditional gene/codon position partitioning, was used to help distinguish phylogenetic signal from noise on a per-site basis. Resulting improvements in topology and nodal support, along with decreased computational effort, suggest that this partitioning strategy may be useful for future studies in phylogenetics and phylogenomics. PMID:24148989

  19. Maximum wind radius estimated by the 50 kt radius: improvement of storm surge forecasting over the western North Pacific

    Science.gov (United States)

    Takagi, Hiroshi; Wu, Wenjie

    2016-03-01

    Even though the maximum wind radius (Rmax) is an important parameter in determining the intensity and size of tropical cyclones, it has been overlooked in previous storm surge studies. This study reviews the existing estimation methods for Rmax based on central pressure or maximum wind speed. These over- or underestimate Rmax because of substantial variations in the data, although an average radius can be estimated with moderate accuracy. As an alternative, we propose an Rmax estimation method based on the radius of the 50 kt wind (R50). Data obtained by a meteorological station network in the Japanese archipelago during the passage of strong typhoons, together with the JMA typhoon best track data for 1990-2013, enabled us to derive the following simple equation, Rmax = 0.23 R50. Application to a recent strong typhoon, the 2015 Typhoon Goni, confirms that the equation provides a good estimation of Rmax, particularly when the central pressure became considerably low. Although this new method substantially improves the estimation of Rmax compared to the existing models, estimation errors are unavoidable because of fundamental uncertainties regarding the typhoon's structure or insufficient number of available typhoon data. In fact, a numerical simulation for the 2013 Typhoon Haiyan as well as 2015 Typhoon Goni demonstrates a substantial difference in the storm surge height for different Rmax. Therefore, the variability of Rmax should be taken into account in storm surge simulations (e.g., Rmax = 0.15 R50-0.35 R50), independently of the model used, to minimize the risk of over- or underestimating storm surges. The proposed method is expected to increase the predictability of major storm surges and to contribute to disaster risk management, particularly in the western North Pacific, including countries such as Japan, China, Taiwan, the Philippines, and Vietnam.

  20. Persistent millennial-scale climate variability in the eastern tropical North Pacific over the last two glacial cycles

    Science.gov (United States)

    Arellano-Torres, Elsa; Ganeshram, Raja S.; Pichevin, Laetitia E.; Salas-de-Leon, David Alberto

    2015-06-01

    High-resolution sediment records from the eastern tropical North Pacific (ETNP) spanning the last ~240 ka B.P. were studied to document the nature of millennial-scale climatic events in the tropical Pacific and to investigate teleconnection mechanisms. We present organic carbon (%OC) and diffuse spectral reflectivity records as indicative of upwelling and productivity changes off NW Mexico over the middle to late Pleistocene. The new productivity records document the persistence of abrupt millennial-scale changes over the last two glacial cycles. Detailed spectral and wavelet time series analyses show the predominance of longer climatic cycles (2-6 ka) during the last and the penultimate glacial periods. The persistence of millennial variability during the penultimate glacial, in absence of large ice rafted debris events in the North Atlantic, suggests that freshwater input through ice sheet dynamics is not essential for millennial-scale climate variability. Given the worldwide emerging picture of remarkable similar millennial-scale records over long time periods, we suggest that the pacing of this climate variability may represent a natural resonance in the climate system, amplified by a tightly coupled oceanic and atmospheric teleconnection processes. We present a schematic scenario of millennial-scale climate change depicting the role of the tropical Pacific in this global teleconnection system by linking productivity and upwelling changes in the ETNP with shifts in the position of the Intertropical Convergence Zone and the strength of the subtropical North Pacific High.

  1. Variability in the correlation between Asian dust storms and chlorophyll a concentration from the North to Equatorial Pacific.

    Science.gov (United States)

    Tan, Sai-Chun; Yao, Xiaohong; Gao, Hui-Wang; Shi, Guang-Yu; Yue, Xu

    2013-01-01

    A long-term record of Asian dust storms showed seven high-occurrence-frequency centers in China. The intrusion of Asian dust into the downwind seas, including the China seas, the Sea of Japan, the subarctic North Pacific, the North Pacific subtropical gyre, and the western and eastern Equatorial Pacific, has been shown to add nutrients to ocean ecosystems and enhance their biological activities. To explore the relationship between the transported dust from various sources to the six seas and oceanic biological activities with different nutrient conditions, the correlation between monthly chlorophyll a concentration in each sea and monthly dust storm occurrence frequencies reaching the sea during 1997-2007 was examined in this study. No correlations were observed between dust and chlorophyll a concentration in the atmospheric deposition is commonly believed to exert less impact on coastal seas. Significant correlations existed between dust sources and many sea areas, suggesting a link between dust and chlorophyll a concentration in those seas. However, the correlation coefficients were highly variable. In general, the correlation coefficients (0.54-0.63) for the Sea of Japan were highest, except for that between the subarctic Pacific and the Taklimakan Desert, where it was as high as 0.7. For the >50 m China seas and the North Pacific subtropical gyre, the correlation coefficients were in the range 0.32-0.57. The correlation coefficients for the western and eastern Equatorial Pacific were relatively low (dust sources, the transport pathways, the dust deposition, the nutrient conditions of oceans, and the probability of dust storms reaching the seas.

  2. Active Pacific North America Plate boundary tectonics as evidenced by seismicity in the oceanic lithosphere offshore Baja California, Mexico

    Science.gov (United States)

    Hauksson, Egill; Kanamori, Hiroo; Stock, Joann; Cormier, Marie-Helene; Legg, Mark

    2014-03-01

    Pacific Ocean crust west of southwest North America was formed by Cenozoic seafloor spreading between the large Pacific Plate and smaller microplates. The eastern limit of this seafloor, the continent-ocean boundary, is the fossil trench along which the microplates subducted and were mostly destroyed in Miocene time. The Pacific-North America Plate boundary motion today is concentrated on continental fault systems well to the east, and this region of oceanic crust is generally thought to be within the rigid Pacific Plate. Yet, the 2012 December 14 Mw 6.3 earthquake that occurred about 275 km west of Ensenada, Baja California, Mexico, is evidence for continued tectonism in this oceanic part of the Pacific Plate. The preferred main shock centroid depth of 20 km was located close to the bottom of the seismogenic thickness of the young oceanic lithosphere. The focal mechanism, derived from both teleseismic P-wave inversion and W-phase analysis of the main shock waveforms, and the 12 aftershocks of M ˜3-4 are consistent with normal faulting on northeast striking nodal planes, which align with surface mapped extensional tectonic trends such as volcanic features in the region. Previous Global Positioning System (GPS) measurements on offshore islands in the California Continental Borderland had detected some distributed Pacific and North America relative plate motion strain that could extend into the epicentral region. The release of this lithospheric strain along existing zones of weakness is a more likely cause of this seismicity than current thermal contraction of the oceanic lithosphere or volcanism. The main shock caused weak to moderate ground shaking in the coastal zones of southern California, USA, and Baja California, Mexico, but the tsunami was negligible.

  3. Assessment of tsunami hazards for the Central American Pacific coast from southern Mexico to northern Peru

    Science.gov (United States)

    Brizuela, B.; Armigliato, A.; Tinti, S.

    2014-07-01

    Central America (CA), from Guatemala to Panama, has been struck by at least 52 tsunamis between 1539 and 2013, and in the extended region from Mexico to northern Peru (denoted as ECA, Extended Central America in this paper) the number of recorded tsunamis in the same time span is more than 100, most of which were triggered by earthquakes located in the Middle American Trench that runs parallel to the Pacific coast. The most severe event in the catalogue is the tsunami that occurred on 2 September 1992 off Nicaragua, with run-up measured in the range of 5-10 m in several places along the Nicaraguan coast. The aim of this paper is to assess the tsunami hazard on the Pacific coast of this extended region, and to this purpose a hybrid probabilistic-deterministic analysis is performed, that is adequate for tsunamis generated by earthquakes. More specifically, the probabilistic approach is used to compute the Gutenberg-Richter coefficients of the main seismic tsunamigenic zones of the area and to estimate the annual rate of occurrence of tsunamigenic earthquakes and their corresponding return period. The output of the probabilistic part of the method is taken as input by the deterministic part, which is applied to calculate the tsunami run-up distribution along the coast.

  4. Shark tooth weapons from the 19th Century reflect shifting baselines in Central Pacific predator assemblies.

    Science.gov (United States)

    Drew, Joshua; Philipp, Christopher; Westneat, Mark W

    2013-01-01

    The reefs surrounding the Gilbert Islands (Republic of Kiribati, Central Pacific), like many throughout the world, have undergone a period of rapid and intensive environmental perturbation over the past 100 years. A byproduct of this perturbation has been a reduction of the number of shark species present in their waters, even though sharks play an important in the economy and culture of the Gilbertese. Here we examine how shark communities changed over time periods that predate the written record in order to understand the magnitude of ecosystem changes in the Central Pacific. Using a novel data source, the shark tooth weapons of the Gilbertese Islanders housed in natural history museums, we show that two species of shark, the Spot-tail (Carcharhinus sorrah) and the Dusky (C. obscurus), were present in the islands during the last half of the 19(th) century but not reported in any historical literature or contemporary ichthyological surveys of the region. Given the importance of these species to the ecology of the Gilbert Island reefs and to the culture of the Gilbertese people, documenting these shifts in baseline fauna represents an important step toward restoring the vivid splendor of both ecological and cultural diversity. PMID:23573214

  5. Shark tooth weapons from the 19th Century reflect shifting baselines in Central Pacific predator assemblies.

    Directory of Open Access Journals (Sweden)

    Joshua Drew

    Full Text Available The reefs surrounding the Gilbert Islands (Republic of Kiribati, Central Pacific, like many throughout the world, have undergone a period of rapid and intensive environmental perturbation over the past 100 years. A byproduct of this perturbation has been a reduction of the number of shark species present in their waters, even though sharks play an important in the economy and culture of the Gilbertese. Here we examine how shark communities changed over time periods that predate the written record in order to understand the magnitude of ecosystem changes in the Central Pacific. Using a novel data source, the shark tooth weapons of the Gilbertese Islanders housed in natural history museums, we show that two species of shark, the Spot-tail (Carcharhinus sorrah and the Dusky (C. obscurus, were present in the islands during the last half of the 19(th century but not reported in any historical literature or contemporary ichthyological surveys of the region. Given the importance of these species to the ecology of the Gilbert Island reefs and to the culture of the Gilbertese people, documenting these shifts in baseline fauna represents an important step toward restoring the vivid splendor of both ecological and cultural diversity.

  6. 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...

  7. Physical and underway data collected aboard the ROGER REVELLE during cruise RR0914 in the North Pacific Ocean, Philippine Sea and South Pacific Ocean from 2009-11-05 to 2009-11-14 (NODC Accession 0089672)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089672 includes physical and underway data collected aboard the ROGER REVELLE during cruise RR0914 in the North Pacific Ocean, Philippine Sea and...

  8. Physical and underway data collected aboard the Marcus G. Langseth during cruise MGL1208 in the North Pacific Ocean and South Pacific Ocean from 2012-04-30 to 2012-05-26 (NODC Accession 0104335)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0104335 includes physical and underway data collected aboard the Marcus G. Langseth during cruise MGL1208 in the North Pacific Ocean and South...

  9. 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...

  10. Mercury sources, distribution, and bioavailability in the North Pacific Ocean: Insights from data and models

    Science.gov (United States)

    Sunderland, E.M.; Krabbenhoft, D.P.; Moreau, J.W.; Strode, S.A.; Landing, W.M.

    2009-01-01

    Fish harvested from the Pacific Ocean are a major contributor to human methylmercury (MeHg) exposure. Limited oceanic mercury (Hg) data, particularly MeHg, has confounded our understanding of linkages between sources, methylation sites, and concentrations in marine food webs. Here we present methylated (MeHg and dimethylmercury (Me2Hg)) and total Hg concentrations from 16 hydrographie stations in the eastern North Pacific Ocean. We use these data in combination with information from previous cruises and coupled atmospheric-oceanic modeling results to better understand controls on Hg concentrations, distribution, and bioavailability. Total Hg concentrations (average 1.14 ?? 0.38 pM) are elevated relative to previous cruises. Modeling results agree with observed increases and suggest that at present atmospheric Hg deposition rates, basin-wide Hg concentrations will double relative to circa 1995 by 2050. Methylated Hg accounts for up to 29% of the total Hg in subsurface waters (average 260 ??114 fM). We observed lower ambient methylated Hg concentrations in the euphotic zone and older, deeper water masses, which likely result from decay of MeHg and Me2Hg when net production is not occurring. We found a significant, positive linear relationship between methylated Hg concentrations and rates of organic carbon remineralization (r2 = 0.66, p importance of particulate organic carbon (POC) transport and remineralization on the production and distribution of methylated Hg species in marine waters. Specifically, settling POC provides a source of inorganic Hg(II) to microbially active subsurface waters and can also provide a substrate for microbial activity facilitating water column methylation. Copyright 2009 by the American Geophysical Union.

  11. Possible influence of western North Pacific monsoon on TC activity in mid-latitudes of East Asia

    Science.gov (United States)

    Choi, Ki-Seon; Cha, Yumi; Kim, Hae-Dong; Kang, Sung-Dae

    2016-01-01

    This study analyzed the correlation between tropical cyclone (TC) frequency and the Western North Pacific monsoon index (WNPMI), which have both been influential in East Asia's mid-latitude regions during the summer season over the past 37 years (1977-2013). A high positive correlation existed between these two variables, which was not reduced even if El Niño-Southern Oscillation (ENSO) years were excluded. To determine the cause of this positive correlation, the highest (positive WNPMI phase) and lowest WNPMIs (negative WNPMI phase) during a nine-year period were selected to analyze the mean difference between them, excluding ENSO years. In the positive WNPMI phase, TCs were mainly generated in the eastern seas of the tropical and subtropical western North Pacific, passing through the East China Sea and moving northward toward Korea and Japan. In the negative phase, TCs were mainly generated in the western seas of the tropical and subtropical western North Pacific, passing through the South China Sea and moving westward toward China's southern regions. Therefore, TC intensity in the positive phase was stronger due to the acquisition of sufficient energy from the sea while moving a long distance up to East Asia's mid-latitude. Additionally, TCs occurred more in the positive phase. Regarding the difference of the two phases between the 850 and 500-hPa streamlines, anomalous cyclones were strengthened in the tropical and subtropical western North Pacific, whereas anomalous anticyclones were strengthened in East Asia's mid-latitude regions. Due to these two anomalous pressure systems, anomalous southeasterlies developed in East Asia's mid-latitude regions, which played a role in the anomalous steering flows that moved TCs into these regions. Furthermore, due to the anomalous cyclones that developed in the tropical and subtropical western North Pacific, more TCs could be generated in the positive phase. Both the lower and upper tropospheric layers had warm anomalies

  12. Anthropogenic warming has decreased water supply in North Central Texas

    Science.gov (United States)

    Brikowski, T. H.

    2015-12-01

    North Central Texas, including Dallas-Ft. Worth, the 4th largest metropolitan area in the U.S., has been in a state of drought for most of this 21st Century. Seven million residents there depend almost exclusively on surface water resources, and net water storage declined precipitously until record rainfall in early 2015. Part of the decline in water availability can be attributed to reduced runoff, where despite slightly above normal precipitation, natural basin runoff has declined almost 20% since its peak in the mid-1990's. These changes have coincided with 0.85oC warming above the historical 20th Century mean. Prevalent Vertisol (cracking) soils in the region make runoff especially sensitive to climate variations, and make it difficult to apply traditional hydrologic models to investigate climate-runoff links. Non-parametric (empirical) runoff elasticity methods circumvent these limitations, and are applied here, focusing on the Upper Trinity River basin (UTB). Diagrammatic assessment of UTB temperature-precipitation (T-Pr) runoff elasticity indicates persistent warming greatly increases the risk of reduced runoff, based on historical experience. Evaluation of individual parameter elasticity indicates dry periods since 2000 have primarily been T-driven, in contrast to the Pr-driven 1951-6 drought of record. Observed decline in runoff during 2000-2010 is entirely attributable to increased T. Additional runoff declines from 2011-14 were driven by reduced Pr, augmenting the T-driven reductions. These T effects are most prominent to the west, and decline to minimal extent just east of the UTB. The observed warming can be related to anthropogenic CO2 increase with >95% certainty based on comparison of CMIP5 climate model results for the UTB with and without CO2 forcing. UTB runoff fraction of Pr decreased after 1980 with >97.5% certainty. These results strongly indicate that 21st Century 20% decline in runoff from previous century norms is largely attributable to

  13. Influence of hydrography of Central Mexican Pacific in the spatial variation of inorganic nutrients during 2010

    Science.gov (United States)

    Olivos-Ortiz, A.; Gaviño-Rodríguez, J. H.; Quijano-Scheggia, S.; Pelayo-Martinez, G.; Torres-Orozco, E.; Calva-Chavez, M.

    2014-12-01

    The Mexican Central Pacific (MCP) is considered an oligotrophic area that holds important populations of different species with ecological and economic importance like marine mammals, billfish and tunas. Hydrographic mechanisms are responsible to interplay with the biogeochemical cycles of nutrients to support primary productivity for these food webs. It is argued that seasonal upwelling of bottom waters rich in nutrients generates distributed in patches of high-productivity, which are also linked to topographic continental forcing. The goal of this study is determine the presence of water masses, depth of the mixed layer, temperature, salinity, patterns of geostrophic currents and their influence on the spatiotemporal variability of inorganic nutrients. For that pupose, three oceanographic cruises were conducted in January, May-June, and October of 2010 off the coast of the MCP. Each campaign consisted of 15 stations in five perpendicular transects with stations at 2, 50 and 100 nm offshore. At each station samples were taken to determine the concentration of NO3-+ NO2-, NH4+, PO43- and SiO2 at 0, 10, 25, 50, 75, 100, 150 and 200 m depth. CTD casts were made up to 500m to obtain profiles of salinity, temperature, water masses, and identify geostrophic currents (direction and intensity). Identified water masses were: Pacific Tropical Surface Water (PTSW), Pacific Equatorial Surface Water (PESW), Equatorial Pacific Water (EPW), California Current Water (CCW), Subtropical Subsurface Water (STSsW), and Pacific Intermediate Water (PIT); these water masses were present in all three seasons being more clear the presence of CCW during autumn and PTSW in winter. The interaction between coastal topography, geostrophic circulation, and the depth of the mixed layer (55m oceanic part in January and 10m coastal area in October) were the factors that determined the location of areas of high concentration of nutrients. The distribution of nutrients was heterogeneous

  14. February 27, 2010 Chilean Tsunami in Pacific and its Arrival to North East Asia

    Science.gov (United States)

    Zaytsev, Andrey; Pelinovsky, EfiM.; Yalciner, Ahmet C.; Ozer, Ceren; Chernov, Anton; Kostenko, Irina; Shevchenko, Georgy

    2010-05-01

    The outskirts of the fault plane broken by the strong earthquake on February 27, 2010 in Chili with a magnitude 8.8 at the 35km depth of 35.909°S, 72.733°W coordinates generated a moderate size tsunami. The initial amplitude of the tsunami source is not so high because of the major area of the plane was at land. The tsunami waves propagated far distances in South and North directions to East Asia and Wet America coasts. The waves are also recorded by several gauges in Pacific during its propagation and arrival to coastal areas. The recorded and observed amplitudes of tsunami waves are important for the potential effects with the threatening amplitudes. The event also showed that a moderate size tsunami can be effective even if it propagates far distances in any ocean or a marginal sea. The far east coasts of Russia at North East Asia (Sakhalin, Kuriles, Kamchatka) are one of the important source (i.e. November 15, 2006, Kuril Island Tsunami) and target (i.e. February, 27, 2010 Chilean tsunami) areas of the Pacific tsunamis. Many efforts have been spent for establishment of the monitoring system and assessment of tsunamis and development of the mitigation strategies against tsunamis and other hazards in the region. Development of the computer technologies provided the advances in data collection, transfer, and processing. Furthermore it also contributed new developments in computational tools and made the computer modeling to be an efficient tool in tsunami warning systems. In this study the tsunami numerical model NAMI DANCE Nested version is used. NAMI-DANCE solves Nonlinear form of Long Wave (Shallow water) equations (with or without dispersion) using finite difference model in nested grid domains from the source to target areas in multiprocessor hardware environment. It is applied to 2010 Chilean tsunami and its propagation and coastal behavior at far distances near Sakhalin, Kuril and Kamchatka coasts. The main tide gauge records used in this study are from

  15. Principles underlying the epizootiology of viral hemorrhagic septicemia in Pacific herring and other fishes throughout the North Pacific Ocean

    Science.gov (United States)

    Hershberger, Paul K.; Garver, Kyle A.; Winton, James R.

    2016-01-01

    Although viral hemorrhagic septicemia virus (VHSV) typically occurs at low prevalence and intensity in natural populations of Pacific herring (Clupea pallasii) and other marine fishes in the Northeast Pacific Ocean, epizootics of the resulting disease (VHS) periodically occur, often in association with observed fish kills. Here we identify a list of principles, based on a combination of field studies, controlled laboratory experiments, and previously unpublished observations, that govern the epizootiology of VHS in Pacific herring. A thorough understanding of these principles provides the basis for identifying risk factors that predispose certain marine fish populations to VHS epizootics, including the lack of population resistance, presence of chronic viral carriers in a population, copious viral shedding by infected individuals, cool water temperatures, limited water circulation patterns, and gregarious host behavioral patterns. Further, these principles are used to define the epizootiological stages of the disease in Pacific herring, including the susceptible (where susceptible individuals predominate a school or subpopulation), enzootic (where infection prevalence and intensity are often below the limits of reasonable laboratory detection), disease amplification (where infection prevalence and intensity increase rapidly), outbreak (often accompanied by host mortalities with high virus loads and active shedding), recovery (in which the mortality rate and virus load decline owing to an active host immune response), and refractory stages (characterized by little or no susceptibility and where viral clearance occurs in most VHS survivors). In addition to providing a foundation for quantitatively assessing the potential risks of future VHS epizootics in Pacific herring, these principles provide insights into the epizootiology of VHS in other fish communities where susceptible species exist.

  16. Seasonal variation of the upper ocean responding to surface heating in the North Pacific

    Science.gov (United States)

    Lee, Eunjeong; Noh, Yign; Qiu, Bo; Yeh, Sang-Wook

    2015-08-01

    Seasonal variations of the upper ocean, such as mixed layer depth (MLD) and sea surface temperature (SST), responding to the atmospheric forcing in the North Pacific (10°N-50°N), are investigated by analyzing the Argo and NCEP/NCAR reanalysis 1 data. The OAFlux data are also used for comparison. During the early heating period in the high-latitude ocean north of 30°N, where a seasonal thermocline is formed above the deep mixed layer under strong surface heating, the MLD h is found to be scaled as h∝>(Lλ>)1/2, where L is the Monin-Obukhov length scale and λ is the Ekman length scale. On the other hand, in the low-latitude ocean south of 30°N, where the preexisting MLD is shallow and surface heating is weak, h is found to be scaled by λ. It is found that a large amount of heat flux across the MLD occurs, especially in the high-latitude ocean during the late heating period, in which h is small. It suggests the contribution by turbulent mixing across the MLD in addition to radiation penetration, and the eddy diffusivity in the high-latitude ocean is estimated as Kv ˜ 10-4-10-3 m2 s-1. The heat budget of the mixed layer reveals that the contribution from the ocean heat transport is much smaller than the surface heat flux in the high-latitude ocean except in the Kuroshio region, but it is sometimes comparable in the low-latitude ocean.

  17. 226Ra evidence for the ecosystem shift over the past 40 years in the North Pacific Subtropical Gyre

    Institute of Scientific and Technical Information of China (English)

    YANG JunHong; CHEN Min; QIU YuSheng; LI YanPing; MA Qiang; L(U) E; ZHANG Run; HUANG YiPu

    2007-01-01

    Surface seawater was collected for 226Ra measurement in the North Pacific Subtropical Gyre from July to October, 1999 and October to December, 2003. Combined with the historical data reported for this sea area, a declined trend of surface 226Ra concentrations was observed since 1960s, indicating the ecosystem shift in response to global warming. On one side, the enhanced stratification of the upper water column resulting from global warming reduced the 226Ra input from the depth, on the other, the temporal increase of biological production resulting from the climate-related ecosystem structure change strengthened the 226Ra removal from the surface ocean. Both the physical and biological processes resulted in the decrease of surface 226Ra concentrations in the North Pacific Subtropical Gyre. The temporal trend of surface 226Ra concentrations was consistent with the trends of chlorophyll a, silicate, phosphate and primary production previously reported. This study provided 226Ra evidence for the ecosystem shift under global change.

  18. On the source of cross-grain lineations in the central Pacific gravity field

    Science.gov (United States)

    McAdoo, David C.; Sandwell, David T.

    1989-07-01

    Subtle lineations in the marine gravity field of the central Pacific derived from Seasat altimeter data were observed by Haxby and Weissel (1986). They suggested that these "cross-grain" lineations were evidence of small-scale convection beneath the Pacific plate. We have examined these features by comparing multiple, collinear gravity and bathymetry profiles in the Fourier transform domain. Our nine gravity profiles were each obtained by stacking (averaging) three or more individual, repeat Geosat/ERM altimeter passes. Prior to stacking, the individual Geosat passes were fit to a cubic spline and then differentiated along track to produce along-track deflections of the vertical (or horizontal gravity). Corresponding bathymetric profiles were produced by projecting, onto Geosat ground tracks, bathymetric observations from six R/V Thomas Washington legs and three R/V Conrad legs that virtually coincide with these Geosat tracks. After Fourier transforming the resulting gravity and bathymetry profiles, we estimate admittances of gravity to bathymetry. These admittances are generally low; they also tend to be negative at very short wavelengths (λ<50 km). They are consistent with models of flexural isostatic compensation by a very thin lithosphere (approximately 2 km). They are not consistent with models of dynamic compensation. We suggest, therefore, that either (1) these cross-grain lineations began to form very near the East Pacific Rise or (2) they formed on older, anomalously weak lithosphere. We also suggest that the gravity lineations result primarily from loads beneath the seafloor in combination with, secondarily, loads on the seafloor. Depths of these subseafloor loads appear not to exceed significantly typical Moho depths.

  19. Nineteenth-century Ship-based Catches of Gray Whales, Eschrichtius robustus, in the Eastern North Pacific

    OpenAIRE

    Reeves, Randall R.; Smith, Tim D.; Lund, Judith N.; Lebo, Susan A.; Josephson , Elizabeth A.

    2010-01-01

    The 19th century commercial ship-based fishery for gray whales, Eschrichtius robustus, in the eastern North Pacific began in 1846 and continued until the mid 1870’s in southern areas and the 1880’s in the north. Henderson identified three periods in the southern part of the fishery: Initial, 1846–1854; Bonanza, 1855–1865; and Declining, 1866–1874. The largest catches were made by “lagoon whaling” in or immediately outside the whale population’s main wintering areas in Mexico—Magdalena Bay, Sc...

  20. The change features of the west boundary bifurcation line of the North Equatorial Current in the Pacific

    Science.gov (United States)

    Guo, Junru; Liu, Yulong; Song, Jun; Bao, Xianwen; Li, Yan; Chen, Shaoyang; Yang, Jinkun

    2015-12-01

    The equatorial Current in the North Pacific (NEC) is an upper layer westward ocean current, which flows to the west boundary of the ocean, east of the Philippines, and bifurcates into the northerly Kuroshio and the main body of the southerly Mindanao current. Thus, NEC is both the south branch of the Subtropical Circulation and the north branch of the Tropical Circulation. The junction of the two branches extends to the west boundary to connect the bifurcation points forming the bifurcation line. The position of the North Pacific Equatorial Current bifurcation line of the surface determines the exchange between and the distribution of subtropical and tropical circulations, thus affecting the local or global climate. A new identification method to track the line and the bifurcation channel was used in this study, focusing on the climatological characteristics of the western boundary of the North Equatorial Current bifurcation line. The long-term average NEC west boundary bifurcation line shifts northwards with depth. In terms of seasonal variation, the average position of the western boundary of the bifurcation line is southernmost in June and northernmost in December, while in terms of interannual variation, from spring to winter in the years when ENSO is developing, the position of the west boundary bifurcation line of NEC is relatively to the north (south) in EI Niño (La Niña) years as compared to normal years.

  1. Distribution and air-sea exchange of organochlorine pesticides in the North Pacific and the Arctic

    Science.gov (United States)

    Cai, Minghong; Ma, Yuxin; Xie, Zhiyong; Zhong, Guangcai; MöLler, Axel; Yang, Haizhen; Sturm, Renate; He, Jianfeng; Ebinghaus, Ralf; Meng, Xiang-Zhou

    2012-03-01

    Surface seawater and boundary layer air samples were collected on the icebreaker Xuelong (Snow Dragon) during the Fourth Chinese Arctic Research Expedition (CHINARE2010) cruise in the North Pacific and Arctic Oceans during 2010. Samples were analyzed for organochlorine pesticides (OCPs), including three isomers of hexachlorocyclohexane (HCH), hexachlorobenzene (HCB), and two isomers of heptachlor epoxide. The gaseous total HCH (ΣHCHs) concentrations were approximately four times lower (average 12.0 pg m-3) than those measured during CHINARE2008 (average 51.4 pg m-3), but were comparable to those measured during CHINARE2003 (average 13.4 pg m-3) in the same study area. These changes are consistent with the evident retreat of sea ice coverage from 2003 to 2008 and increase of sea ice coverage from 2008 to 2009 and 2010. Gaseous β-HCH concentrations in the atmosphere were typically below the method detection limit, consistent with the expectation that ocean currents provide the main transport pathway for β-HCH into the Arctic. The concentrations of all dissolved HCH isomers in seawater increase with increasing latitude, and levels of dissolved HCB also increase (from 5.7 to 7.1 pg L-1) at high latitudes (above 73°N). These results illustrate the role of cold condensation processes in the transport of OCPs. The observed air-sea gas exchange gradients in the Arctic Ocean mainly favored net deposition of OCPs, with the exception of those for β-HCH, which favored volatilization.

  2. Behavior of 137Cs concentrations in the North Pacific in an ocean general circulation model

    Science.gov (United States)

    Tsumune, Daisuke; Aoyama, Michio; Hirose, Katsumi

    2003-08-01

    We have carried out a first simulation of the spatial distributions and the temporal variations of 137Cs concentrations in the North Pacific in off line calculations by using archived output of an ocean general circulation model (OGCM) developed by the National Center of Atmospheric Research (NCAR). Artificial radionuclides including 137Cs are introduced into ocean surface due to global fallout originating from the large-scale atmospheric nuclear weapons tests in 1961-1962. The distribution of radioactive deposition used as forcing for this simulation is estimated from global precipitation data and observed values of annual deposition of radionuclides at the Meteorological Research Institute (MRI) in Japan. 137Cs originating from global fallout have been transported into the ocean interior by advection and diffusion, and the 137Cs concentrations reduced by radioactive decay. We assess the skill of the model calculations by comparing simulated values of 137Cs in seawater with the observed values included in the database compiled by MRI because 137Cs is one of the most useful tracers regarding water motion in the ocean. The vertical and horizontal distributions of the calculated 137Cs concentrations were in good agreement with those of the observed 137Cs concentrations, except in the deep layer.

  3. Occurrence and diversity of mesophilic Shewanella strains isolated from the North-West Pacific Ocean.

    Science.gov (United States)

    Ivanova, Elena P; Sawabe, Tomoo; Zhukova, Natalia V; Gorshkova, Nataliya M; Nedashkovskaya, Olga I; Hayashi, Karin; Frolova, Galina M; Sergeev, Alexander F; Pavel, Konstantin G; Mikhailov, Valery V; Nicolau, Dan V

    2003-06-01

    Although bacteria of the genus Shewanella belong to one of the readily cultivable groups of "Gammaproteobacteria", little is known about the occurrence and abundance of these microorganisms in the marine ecosystem. Studies revealed that of 654 isolates obtained from marine invertebrates (ophiuroid Amphiopholis kochii, sipuncula Phascolosoma japonicum, and holothurian Apostichopus japonicus, Cucumaria japonica), seawater and sediments of the North-West Pacific Ocean (i.e. the Sea of Japan and Iturup Is, Kurile Islands), 10.7% belonged to the genus Shewanella. The proportion of viable Shewanella species varied from 4% to 20% depending on the source of isolation. From the isolation study, representative strains of different phenotypes (from seventy presumptive Shewanella strains) were selected for detailed characterization using phenotypic, chemotaxonomic, and phylogenetic testing. 16S rDNA sequence-based phylogenetic analysis confirmed the results of tentative identification and placed the majority of these strains within only a few species of the genus Shewanella with 98-99% of 16S rDNA sequences identity mainly with S. japonica and S. colwelliana, suggesting that the strains studied might belong to these species. Numerically dominant strains of S. japonica were metabolically active and produced proteinases (gelatinases, caseinases), lipases, amylases, agarases, and alginases. Shewanella strains studied demonstrated weak antimicrobial and antifungal activities that might be an indication of their passive role in the colonization on living and non-living surfaces. PMID:12866857

  4. Can the climate background of western North Pacific typhoon activity be predicted by climate model?

    Institute of Scientific and Technical Information of China (English)

    LANG XianMei; WANG HuiJun

    2008-01-01

    Based on the observation and reanalysis data through 1948-2004, the vertical shear of zonal wind, outgoing Iongwave radiation, and divergence fields in the lower and upper troposphere during summer are revealed to correlate significantly with the concurrent western North Pacific (WNP) typhoon frequency, and they therefore can be regarded as predictors for the WNP typhoon activity anomaly. After that, the 34-year (1970-2003) ensemble hindcast experiments are performed by the nine-level atmospheric general circulation model developed at the Institute of Atmospheric Physics Under the Chinese Academy of Sciences (IAP9L-AGCM), aiming to investigate the numerical predictability of the summer vertical shear of zonal wind and divergence field in the lower troposphere. It is found that the temporal correlation coefficients between the hindcast and observation are 0.70 and 0.62 for the vertical shear of zonal wind and divergence field, respectively. This suggests that the model possesses a large potential skill for predicting the large-scale climate background closely related to the WNP typhoon activity, and the model is therefore capable of performing the real-time numerical prediction of the WNP typhoon activity anomaly to some extent.

  5. Sequential megafaunal collapse in the North Pacific Ocean: An ongoing legacy of industrial whaling?

    Science.gov (United States)

    Springer, A.M.; Estes, J.A.; Van Vliet, G. B.; Williams, T.M.; Doak, D.F.; Danner, E.M.; Forney, K.A.; Pfister, B.

    2003-01-01

    Populations of seals, sea lions, and sea otters have sequentially collapsed over large areas of the northern North Pacific Ocean and southern Bering Sea during the last several decades. A bottom-up nutritional limitation mechanism induced by physical oceanographic change or competition with fisheries was long thought to be largely responsible for these declines. The current weight of evidence is more consistent with top-down forcing. Increased predation by killer whales probably drove the sea otter collapse and may have been responsible for the earlier pinniped declines as well. We propose that decimation of the great whales by post-World War II industrial whaling caused the great whales' foremost natural predators, killer whales, to begin feeding more intensively on the smaller marine mammals, thus "fishing-down" this element of the marine food web. The timing of these events, information on the abundance, diet, and foraging behavior of both predators and prey, and feasibility analyses based on demographic and energetic modeling are all consistent with this hypothesis.

  6. Radiative forcing due to dust aerosol over east Asia-north Pacific region during spring,2001

    Institute of Scientific and Technical Information of China (English)

    WANG Hong; SHI Guangyu; Aoki Teruo; WANG Biao; ZHAO Tianliang

    2004-01-01

    An optical model accounting for the East Asian dust is proposed as a result of theory calculation and composition analysis of the aerosol samples collected in China desert during the international project, "Studies on the Origin and Transport of Aeolian Dust and its Effects on Climate (ADEC)". Study indicates that dust aerosols emitting from China deserts have smaller imaginary parts of refractive indices, therefore absorb less and scatter more solar radiation than the most dust optical models published so far. Furthermore, the forward fraction of scattering is less and the backscattering is stronger than those of the other models. The seasonal averaged radiative forcing in spring, 2001 over east Asia-north Pacific region is simulated employing the new dust optical model. The net forcing at the top of atmosphere (TOA) is estimated as -0.943 W·m-2 for regional and seasonal mean, with shortwave and longwave contributions of -1.700 and 0.759 W·m-2, respectively. The surface net forcing is calculated to be -5.445 W·m-2, and made up of shortwave component of -6.250 W·m-2 and longwave component of +0.759 W·m-2. The distributions of TOA and surface net forcing over this region are also analyzed in this study.

  7. Simulations of tropical cyclogenesis associated with different monsoon trough patterns over the western North Pacific

    Science.gov (United States)

    Cao, Xi; Chen, Guanghua; Li, Tim; Ren, Fumin

    2016-08-01

    The numerical simulations of tropical cyclone (TC) genesis during the strong and weak monsoon trough (MT) years, in which meteorological fields are composited, are conducted using advanced research weather research and forecasting model. The simulation results show that both tropical disturbances tend to form in the east of the western North Pacific (WNP) near 160°-170°E during the strong and weak MT years. During the strong MT years, there is a faster formation rate of TC. The eastward-extending MT gradually evolves into a closed monsoon gyre over the WNP during the early stage. The following rapid development of TC can be attributed to the enhanced lower-level southwesterly flows induced by the cross-equatorial currents, enhanced easterly winds, and weak vertical wind shear, which provide a favorable environment for TC genesis. The strengthened large-scale circulation spawns abundant convective updrafts resulting in the aggregation of cyclonic vorticity. In contrast, during the weak MT years, the westward-retreated MT gradually evolves into expansive easterly winds over the WNP. Two episodes of convective updrafts are triggered with a longer interval, and thus lead to a slower TC genesis compared with that during the strong MT years.

  8. Photic zone changes in the north-west Pacific Ocean from MIS 4–5e

    Directory of Open Access Journals (Sweden)

    G. E. A. Swann

    2015-01-01

    Full Text Available In comparison to other sectors of the marine system, the palaeoceanography of the subarctic North Pacific Ocean is poorly constrained. New diatom isotope records of δ13C, δ18O, δ30Si (δ13Cdiatom, δ18Odiatom, and δ30Sidiatom are presented alongside existing geochemical and isotope records to document changes in photic zone conditions, including nutrient supply and the efficiency of the soft-tissue biological pump, between Marine Isotope Stage (MIS 4 and MIS 5e. Peaks in opal productivity in MIS 5b/c and MIS 5e are both associated with the breakdown of the regional halocline stratification and increased nutrient supply to the photic zone. Whereas the MIS 5e peak is associated with low rates of nutrient utilisation, the MIS 5b/c peak is associated with significantly higher rates of nutrient utilisation. Both peaks, together with other smaller increases in productivity in MIS 4 and 5a, culminate with a significant increase in freshwater input which strengthens/re-establishes the halocline and limits further upwelling of sub-surface waters to the photic zone. Whilst δ30Sidiatom and previously published records of diatom δ15N (δ15Ndiatom (Brunelle et al., 2007, 2010 show similar trends until the latter half of MIS 5a, the records become anti-correlated after this juncture and into MIS 4, suggesting a possible change in photic zone state such as may occur with a shift to iron or silicon limitation.

  9. Fast and Slow Responses of the North Pacific Mode Water and Subtropical Countercurrent to Global Warming

    Institute of Scientific and Technical Information of China (English)

    XU Lixiao; XIE Shang-Ping; LIU Qinyu

    2013-01-01

    Six coupled general circulation models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) are employed for examining the full evolution of the North Pacific mode water and Subtropical Countercurrent (STCC) under global warming over 400 years following the Representative Concentration Pathways (RCP) 4.5.The mode water and STCC first show a sharp weakening trend when the radiative forcing increases,but then reverse to a slow strengthening trend of smaller magnitude after the radiative forcing is stablized.As the radiative forcing increases during the 21 st century,the ocean warming is surface-intensified and decreases with depth,strengthening the upper ocean's stratification and becoming unfavorable for the mode water formation.Moving southward in the subtropical gyre,the shrinking mode water decelerates the STCC to the south.After the radiative forcing is stabilized in the 2070s,the subsequent warming is greater at the subsurface than at the sea surface,destabilizing the upper ocean and becoming favorable for the mode water formation.As a result,the mode water and STCC recover gradually after the radiative forcing is stabilized.

  10. Enhanced Particulate Organic Carbon Export at Eddy Edges in the Oligotrophic Western North Pacific Ocean.

    Directory of Open Access Journals (Sweden)

    Yung-Yen Shih

    Full Text Available Mesoscale eddies in the subtropical oligotrophic ocean are ubiquitous and play an important role in nutrient supply and oceanic primary production. However, it is still unclear whether these mesoscale eddies can efficiently transfer CO2 from the atmosphere to deep waters via biological pump because of the sampling difficulty due to their transient nature. In 2007, particulate organic carbon (POC fluxes, measured below the euphotic zone at the edge of warm eddy were 136-194 mg-C m-2 d-1 which was greatly elevated over that (POC flux = 26-35 mg-C m-2 d-1 determined in the nutrient-depleted oligotrophic waters in the Western North Pacific (WNP. In 2010, higher POC fluxes (83-115 mg-C m-2 d-1 were also observed at the boundary of mesoscale eddies in the WNP. The enhanced POC flux at the edge of eddies was mainly attributed to both large denuded diatom frustules and zooplankton fecal pellets based on scanning electron microscopy (SEM examination. The result suggests that mesoscale eddies in the oligotrophic waters in the subtropical WNP can efficiently increase the oceanic carbon export flux and the eddy edge is a crucial conduit in carbon sequestration to deep waters.

  11. Ecogenomic sensor reveals controls on N2-fixing microorganisms in the North Pacific Ocean.

    Science.gov (United States)

    Robidart, Julie C; Church, Matthew J; Ryan, John P; Ascani, François; Wilson, Samuel T; Bombar, Deniz; Marin, Roman; Richards, Kelvin J; Karl, David M; Scholin, Christopher A; Zehr, Jonathan P

    2014-06-01

    Nitrogen-fixing microorganisms (diazotrophs) are keystone species that reduce atmospheric dinitrogen (N2) gas to fixed nitrogen (N), thereby accounting for much of N-based new production annually in the oligotrophic North Pacific. However, current approaches to study N2 fixation provide relatively limited spatiotemporal sampling resolution; hence, little is known about the ecological controls on these microorganisms or the scales over which they change. In the present study, we used a drifting robotic gene sensor to obtain high-resolution data on the distributions and abundances of N2-fixing populations over small spatiotemporal scales. The resulting measurements demonstrate that concentrations of N2 fixers can be highly variable, changing in abundance by nearly three orders of magnitude in less than 2 days and 30 km. Concurrent shipboard measurements and long-term time-series sampling uncovered a striking and previously unrecognized correlation between phosphate, which is undergoing long-term change in the region, and N2-fixing cyanobacterial abundances. These results underscore the value of high-resolution sampling and its applications for modeling the effects of global change. PMID:24477197

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

    Directory of Open Access Journals (Sweden)

    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.

  13. 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

  14. Effect of horizontal grid resolution on simulations of the subtropical mode water in the North Pacific

    Science.gov (United States)

    Lee, Ho Jin; Yeop Kim, Sang; Lee, Kyung Eun

    2016-04-01

    We investigate how the Subtopical Mode Water (STMW) can be simulated differently in the North Pacific using a global Ocean General Circulation Model (OGCM) with non-eddying and eddy permitting resolution. The OGCM used in this study is the MOM version 4.1 and has a total of 50 levels along the vertical direction with enhanced resolution near the surface. The CORE version 2 (normal year forcing) data derived from the air-sea flux climatology averaged over 60 years (1948‑2007) are used to calculate heat, salt and momentum fluxes with a bulk formula at the sea surface. The sea surface salinity is restored to the climatological monthly mean surface salinity of the Polar Science Center Hydrographic Climatology on a 60-day timescale, to make up the fresh water flux at the sea surface. Two models that have horizontal resolutions of 1° and 1/4 °, respectively, are integrated during 50 years. The inter-annual variation of the STMW volume was well reproduced with the eddy-permitting grid resolution although the model was forced by a climatological atmospheric forcing. The annual formation and erosion volume of STMW varies by 7% and 9% of the mean volume, respectively.

  15. NOAA marine environmental buoy data from the National Data Buoy Center in the Gulf of Alaska, Gulf of Mexico, Bering Sea, North Atlantic Ocean, North Pacific Ocean, Coastal Waters of SE Alaska, Coastal Waters of Western U.S., Great Lakes, North American Coastline-North, and North American Coastline-South from 2002-10-01 to 2002-10-31 (NODC Accession 0000400)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Pressure, temperature, and other data were collected from fixed platforms in the Gulf of Alaska, Gulf of Mexico, Bering Sea, North Atlantic Ocean, North Pacific...

  16. Seasonal variations in planktonic foraminiferal flux and oxygen isotopic composition in the western North Pacific : Implications for paleoceanographic reconstruction

    OpenAIRE

    SAGAWA, Takuya; Kuroyanagi, Azumi; Irino, Tomohisa; Kuwae, Michinobu; Kawahata, Hodaka

    2013-01-01

    The oxygen isotopic composition (delta O-18) of planktonic foraminiferal shells in seafloor sediment provides information on past surface oceanography. Knowledge of seasonal and depth habitat, as well as the delta O-18 disequilibrium (vital effect), is essential to constrain the interpretation of sedimentary delta O-18. Here, we present a 1-year time series of planktonic foraminiferal shell fluxes and delta(18)Ofrom a sediment trap moored in the northwestern margin of the North Pacific. The v...

  17. Whales, dolphins, and porpoises of the eastern North Pacific and adjacent Arctic waters: a guide to their identification

    OpenAIRE

    Leatherwood, Stephen; Randall R Reeves; Perrin, William F; William E Evans; Hobbs, Larry

    1982-01-01

    This is an identification guide for cetaceans (whales, dolphins, and porpoises), that was designed to assist laymen in identifying cetaceans encountered in eastern North Pacific and Arctic waters. It was intended for use by ongoing cetacean observer programs. This is a revision of an earlier guide with the same title published in 1972 by the Naval Undersa Center and the National Marine Fisheries Service. It includes sections on identifying cetaceans at sea as well as stranded animals on sh...

  18. Physical and underway data collected aboard the NEW HORIZON during cruise NH1502 in the North Pacific Ocean on 2015-02-18 (NCEI Accession 0145830)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0145830 includes physical and underway data collected aboard the NEW HORIZON during cruise NH1502 in the North Pacific Ocean on 2015-02-18. These...

  19. Salinity and sigma-t data from moored current meter and CTD casts in the North Pacific Ocean from 26 August 1979 - 07 June 1982 (NODC Accession 8200146)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Salinity and sigma-t data were collected using moored current meter and CTD casts in the North Pacific Ocean from August 26, 1979 to June 7, 1982. Data were...

  20. Chemical and temperature profile data from CTD casts in the East China Sea, Sea of Japan, and North Pacific Ocean (NODC Accession 9700022)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Chemical and temperature profile data were collected from CTD casts in the East China Sea, Sea of Japan, and North Pacific Ocean. Data were submitted by the Japan...

  1. Physical and underway data collected aboard the NEW HORIZON during cruise NH1313 in the North Pacific Ocean on 2013-06-04 (NCEI Accession 0132108)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0132108 includes physical and underway data collected aboard the NEW HORIZON during cruise NH1313 in the North Pacific Ocean on 2013-06-04. These...

  2. Current meter and temperature profile data from current meter and buoy casts in the North Pacific Ocean from 01 October 1997 to 31 August 1998 (NODC Accession 9800144)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Current meter and temperature profile data were collected using current meter and buoy casts in the North Pacific Ocean from 01 October 1997 to 31 August 1998. Data...

  3. 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...

  4. Plankton data collected using net casts from the FRANCISCO DE ULLOA in the North Pacific Ocean from 15 July 1998 to 30 July 1998 (NODC Accession 0000911)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Plankton data were collected using net casts in the North Pacific Ocean from FRANCISCO DE ULLOA. Data were collected from 15 July 1998 to 30 July 1998. Data were...

  5. Zooplankton data collected using net casts from the FRANCISCO DE ULLOA in the North Pacific Ocean from 01 January 1999 to 31 January 1999 (NODC Accession 0000912)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Zooplankton data were collected using net casts in the North Pacific Ocean from FRANCISCO DE ULLOA. Data were collected from 01 January 1999 to 31 January 1999....

  6. Genetic diversity in two introduced biofouling amphipods (Amphipods valida and Jassa marmorata) along the Pacific North American coast: investigation into molecular identification and cryptic diversity

    Science.gov (United States)

    We investigated patterns of genetic diversity among invasive populations of A. valida and J. marmorata from the Pacific North American coast to assess the accuracy of morphological identification and determine whether or not cryptic diversity and multiple introductions contribute...

  7. Physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1406 in the North Pacific Ocean on 2014-10-22 (NCEI Accession 0150629)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150629 includes physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1406 in the North Pacific Ocean on 2014-10-22....

  8. Physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1211 in the North Pacific Ocean on 2012-07-14 (NCEI Accession 0134541)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0134541 includes physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1211 in the North Pacific Ocean on 2012-07-14....

  9. Physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1509 in the North Pacific Ocean on 2015-06-02 (NCEI Accession 0145849)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0145849 includes physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1509 in the North Pacific Ocean on 2015-06-02....

  10. Physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1212 in the North Pacific Ocean on 2012-07-15 (NCEI Accession 0134542)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0134542 includes physical and underway data collected aboard the ROBERT GORDON SPROUL during cruise SP1212 in the North Pacific Ocean on 2012-07-15....

  11. Shallow-water zoantharians (Cnidaria, Hexacorallia from the Central Indo-Pacific

    Directory of Open Access Journals (Sweden)

    James Reimer

    2014-10-01

    Full Text Available Despite the Central Indo-Pacific (CIP and the Indonesian Archipelago being a well-known region of coral reef biodiversity, particularly in the ‘Coral Triangle’, little published information is available on its zoantharians (Cnidaria: Hexacorallia: Zoantharia. In order to provide a basis for future research on the Indo-Pacific zoantharian fauna and facilitate comparisons between more well-studied regions such as Japan and the Great Barrier Reef, this report deals with CIP zoantharian specimens in the Naturalis collection in Leiden, the Netherlands; 106 specimens were placed into 24 morpho-species and were supplemented with 88 in situ photographic records from Indonesia, the Philippines, and Papua New Guinea. At least nine morpho-species are likely to be undescribed species, indicating that the region needs more research in order to properly understand zoantharian diversity within the CIP. The Naturalis’ zoantharian specimens are listed by species, as well as all relevant collection information, and in situ images are provided to aid in future studies on zoantharians in the CIP.

  12. An Assessment of Multi-model Simulations on the Variability of Western North Pacific Tropical Cyclones and Its Association with ENSO

    Science.gov (United States)

    Han, Rongqing; Wang, Hui; Hu, Zeng-Zhen; Kumar, Arun; Li, Weijing; Long, Lindsey N.; Schemm, Jae-Kyung E.; Peng, Peitao; Wang, Wanqiu; Si, Dong; Jia, Xiaolong; Zhao, Ming; Vecchi, Gabriel A.; Larow, Timothy E.; Lim, Young-Kwon; Schubert, Siegfried D.; Camargo, Suzana J.; Henderson, Naomi; Jonas, Jeffrey A.; Walsh, Kevin J. E.

    2016-04-01

    An assessment on the simulations of interannual variability of tropical cyclones (TCs) over the western North Pacific (WNP) and association with El Niño-Southern Oscillation (ENSO), as well as a subsequent diagnosis for possible causes of the model biases generated from simulating the large scale climate conditions, are documented in the paper. The model experiments are carried out by the Hurricane Work Group under the U.S. Climate Variability and Predictability Research Program (CLIVAR) using five global climate models (GCMs) with a total of 16 ensemble members forced by the observed sea surface temperature, and spanning 28-yr period from 1982 to 2009. The results show GISS and GFDL model ensemble means best simulate the interannual variability of TCs and the multi-model ensemble mean (MME) follows. Also, the MME has the closest climate mean annual number of WNP TCs and the smallest root-mean-square error to the observation. Most GCMs can simulate the interannual variability of WNP TCs well, with stronger TC activities during two types of El Niño, namely eastern Pacific (EP) and central Pacific (CP) El Niño, and weaker activity during La Niña. However, none of models captures the differences in TC activity between EP and CP El Niño as shown in observations, which may be due to the bias of the circulations in models in response to the westward shift of tropical heating associated with CP El Niño. In addition, a general unrealistic scene exists in model simulations with the underestimated intensities of the convection anomaly over the maritime continent in the western tropical Pacific during each ENSO phase of whatever warm or cold, which may be the important source of biases in simulating WNP TC associated with the ENSO events.

  13. Pre-bomb marine reservoir ages in the western north Pacific: Preliminary result on Kyoto University collection

    Energy Technology Data Exchange (ETDEWEB)

    Yoneda, Minoru E-mail: myoneda@nies.go.jp; Kitagawa, Hiroyuki; Plicht, Johannes van der; Uchida, Masao; Tanaka, Atsushi; Uehiro, Takashi; Shibata, Yasuyuki; Morita, Masatoshi; Ohno, Terufumi

    2000-10-01

    The calibration of radiocarbon dates on marine materials involves a global marine calibration with regional corrections. The marine reservoir ages in the Western North Pacific have not been discussed, while it is quite important to determine the timing of palaeo-environmental changes as well as archaeological interpretation around this region. The lack of adequate collection of the pre-bomb shell from western north Pacific was the biggest problem. Recently we had a chance to examine specimens from an old shell collection stored in Kyoto University, including shell specimens from Japan, Korea, Taiwan and the Micronesia of 1920s and 1930s. We explored the possibility for usage of specimen without clear evidence of live collection by measuring 30 apparent radiocarbon ages of pre-bomb mollusk shells from 18 sites in Western North Pacific. The preliminary results showed several discrepancies with previously reported results and with each other. We have to carefully select the shell specimen that has biological signs such as articulating fulcrum. In order to exploit this big resource of pre-bomb shell collection, the new technique to distinguish fossils from live collected samples should be developed by using chemical and physical methods.

  14. Response of Mode Water and Subtropical Countercurrent to Greenhouse Gas and Aerosol Forcing in the North Pacific

    Institute of Scientific and Technical Information of China (English)

    WANG Liyi; LIU Qinyu; XU Lixiao; XIE Shang-Ping

    2013-01-01

    The response of the North Pacific Subtropical Mode Water and Subtropical Countercurrent (STCC) to changes in greenhouse gas (GHG) and aerosol is investigated based on the 20th-century historical and single-forcing simulations with the Geophysical Fluid Dynamics Laboratory Climate Model version 3 (GFDL CM3).The aerosol effect causes sea surface temperature (SST)to decrease in the mid-latitude North Pacific,especially in the Kuroshio Extension region,during the past five decades (1950-2005),and this cooling effect exceeds the warming effect by the GHG increase.The STCC response to the GHG and aerosol forcing are opposite.In the GHG (aerosol) forcing run,the STCC decelerates (accelerates) due to the decreased (increased) mode waters in the North Pacific,resulting from a weaker (stronger) front in the mixed layer depth and decreased (increased) subduction in the mode water formation region.The aerosol effect on the SST,mode waters and STCC more than offsets the GHG effect.The response of SST in a zonal band around 40°N and the STCC to the combined forcing in the historical simulation is similar to the response to the aerosol forcing.

  15. Relationship of regional PM2.5 variations in east Asia and climate variability in the North Pacific

    Science.gov (United States)

    So, J.; Yeh, S. W.; Kim, M.; Park, R.

    2014-12-01

    Recent studies have suggested that the Short Lived Climate Pollutants (SLCPs) such as Sulfate aerosols, Black carbon, Seasalt play a role to influence the weather and climate variability by changing radiative forcings. Therefore, it is useful to examine the relationship between atmospheric variability and SLCPs. Particularly, the concentration of Particle Matter 2.5 (PM2.5) is significant in east Asia, which is mostly due to a rapid industrialization. It is known that both the atmospheric circulation and cloud variability is closely associated with the variations of PM2.5 in east Asia are associated with major atmospheric variables for 1986-2010 using the GEOS-Chem model and the observational datasets. The composite analysis reveals that the high and low concentration year of PM2.5 in east Asia is differently associated with the spatial pattern of atmospheric anomalies over the North Pacific. In addition, the changes in the PM2.5 concentration in east Asia may lead the changes in the amount of high and low cloud in the downstream region of the North Pacific. This indicates that the PM2.5 variations in east Asia may significantly influence the weather and climate variability in the North Pacific by modulating the cloud amount and atmospheric circulation, which is largely consistent with some previous studies.

  16. Molecular phylogeny of Babesia poelea from brown boobies (Sula leucogaster) from Johnston Atoll, Central Pacific

    Science.gov (United States)

    Yabsley, Michael J.; Work, Thierry M.; Rameyer, Robert A.

    2006-01-01

    The phylogenetic relationship of avian Babesia with other piroplasms remains unclear, mainly because of a lack of objective criteria such as molecular phylogenetics. In this study, our objective was to sequence the entire 18S, ITS-1, 5.8S, and ITS-2 regions of the rRNA gene and partial β-tubulin gene of B. poelea, first described from brown boobies (Sula leucogaster) from the central Pacific, and compare them to those of other piroplasms. Phylogenetic analyses of the entire 18S rRNA gene sequence revealed that B. poelea belonged to the clade of piroplasms previously detected in humans, domestic dogs, and wild ungulates in the western United States. The entire ITS-1, 5.8S, ITS-2, and partial β-tubulin gene sequence shared conserved regions with previously described Babesia and Theileria species. The intron of the β-tubulin gene was 45 bp. This is the first molecular characterization of an avian piroplasm.

  17. USGS research on geohazards of the North Pacific: past, present, and future

    Science.gov (United States)

    McNutt, M. K.; Eichelberger, J. C.

    2012-12-01

    The disastrous earthquakes and tsunamis of Sumatra in 2004 and Tohoku in 2011 have driven re-examination of where and how such events occur. Particular focus is on the North Pacific. Of the top 30 earthquakes recorded instrumentally worldwide, 50% occurred along the line of subduction from the Kuril Islands to the southern Alaska mainland. This region has seen monstrous volcanic eruptions (Katmai-Novarupta, 1912), destructive tsunamis (Severo-Kurilsk, 1952), and one of Earth's largest instrumentally-recorded earthquakes (M9.2 Alaska, 1964). Only the modest populations in these frontier towns half a century ago kept losses to a minimum. Impact of any natural disaster to population, vital infrastructure, and sea and air transportation would be magnified today. While USGS had a presence in Alaska for more than a century, the great Alaska earthquake of 1964 ushered in the first understanding of the area's risks. This was the first mega-thrust earthquake properly interpreted as such, and led to re-examination of the 1960 Chilean event. All modern conceptions of mega-thrust earthquakes and tsunamis derive some heritage from USGS research following the 1964 event. The discovery of oil in the Alaska Arctic prompted building a pipeline from the north slope of Alaska to the ice-free port of Valdez. The USGS identified risks from crossing permafrost and active faults. Accurate characterization of these hazards informed innovative designs that kept the pipeline from rupturing due to ground instability or during the M7.9 Denali earthquake of 2002. As a large state with few roads, air travel is common in Alaska. The frequent ash eruptions of volcanoes in the populous Cook Inlet basin became a serious issue, highlighted by the near-crash of a large passenger jet in 1989. In response, the USGS and its partners developed and deployed efficient seismic networks on remote volcanoes and initiated regular satellite surveillance for early warning of ash eruptions. Close collaboration

  18. On the formation of a conservation hotspot for juvenile North Pacific loggerhead sea turtles (Caretta caretta)

    Science.gov (United States)

    Wingfield, Dana K.

    2009-12-01

    This research examined the incorporation of highly productive regions within the marine system. I combined historical conservation literature, remotely sensed oceanography, ship based surveys, satellite tagged animals, and statistical models to explore an integrated approach to the identification of key oceanic regions that require incorporation into current marine conservation strategies. In my first chapter, I undertook a literature review of the term "hotspot", one of the most common ways by which scientists ascribe conservation prioritization in the marine and terrestrial systems. My results showed that marine literature has identified important areas of biodiversity and productivity (i.e. high primary production that results in trophic linkages and species aggregations) are in need of protection from human threats. However, current non-governmental organizations focus primarily on biodiversity, thus missing important areas of productivity for marine conservation. In my second chapter, I demonstrated how remotely sensed oceanography, ship-based surveys, and satellite tagged animals can help to identify the formation of such a "productivity hotspot". Specifically, I examined the connection between physical forcing (surface winds and vertical Ekman upwelling), sea-surface temperature, primary production (chlorophyll-a concentrations), retentive features of fronts and dynamic height, and prey abundance (red crabs) in the spatial and temporal concentration of the critically endangered North Pacific juvenile loggerhead sea turtle (Caretta caretta) within its foraging habitat off the Pacific coast of Baja California. Finally, in my third chapter, I identified habitat selection of loggerheads to better understand the species preference within suitable habitat. I sampled several environmental variables (depth, sea-surface temperature, and chlorophyll- a) within 'preferred' versus 'avoided' turtle habitat. Results from a generalized additive model showed the statistical

  19. Evaluation of radioactive cesium impact from atmospheric deposition and direct release fluxes into the North Pacific from the Fukushima Daiichi nuclear power plant

    Science.gov (United States)

    Tsubono, Takaki; Misumi, Kazuhiro; Tsumune, Daisuke; Bryan, Frank O.; Hirose, Katsumi; Aoyama, Michio

    2016-09-01

    The North Pacific distribution of 134Cs released from the Fukushima Daiichi nuclear power plant (F1NPP) has been investigated using an eddy-resolving model. We conducted simulations based on two scenarios: (1) an input flux that was a combination of atmospheric deposition and direct release from the F1NPP (combination-flux scenario) and (2) an input flux that took account only of the direct release of 134Cs (single-flux scenario). The combination-flux scenario simulation successfully reproduced the distribution of 134Cs activity observed in the surface layer from April 2011 to January 2014. The results indicate that 134Cs deposited via atmospheric deposition into the Kuroshio-Oyashio Interfrontal Zone and 134Cs directly released from F1NPP were both transported to south of the Subarctic Front around 42°N in June of 2012. The combination-flux scenario suggests that the 134Cs activities observed in the area north of 42°N in 2012 originated from atmospheric deposition and that the 134Cs activity was subducted in Central Mode Water during the winters of 2011 and 2012. We directly compared simulated and observed 134Cs activities in the surface layer at 179 points across a wide area to the east of 155°E from 2011 to 2013 to evaluate the accuracy of the two scenarios. The root-mean-square error and correlation coefficient, R, were 7.3 Bq m-3 and 0.86, respectively, for the combination-flux scenario and 13.8 Bq m-3 and 0.46, respectively, for the single-flux scenario, confirming that reproduction of the 134Cs activity in the North Pacific after the F1NPP accident requires taking both fluxes into consideration. Based on a linear least-squares regression between simulated and observed 134Cs activity, the total 134Cs flux into the North Pacific was estimated at 16.1±1.4 PBq.

  20. A comparative study of Taiwan's short-term medical missions to the South Pacific and Central America

    Directory of Open Access Journals (Sweden)

    Chiu Ya-Wen

    2012-12-01

    Full Text Available Abstract Background Taiwan has been dispatching an increasing number of short-term medical missions (STMMs to its allied nations to provide humanitarian health care; however, overall evaluations to help policy makers strengthen the impact of such missions are lacking. Our primary objective is to identify useful strategies by comparing STMMs to the South Pacific and Central America. Methods The data for the evaluation come from two main sources: the official reports of 46 missions to 11 countries in Central America and 25 missions to 8 countries in the South Pacific, and questionnaires completed by health professionals who had participated in the above missions. In Central America, STMMs were staffed by volunteer health professionals from multiple institutions. In the South Pacific, STMMs were staffed by volunteer health professionals from single institutions. Results In comparison to STMMs to Central America, STMMs to the South Pacific accomplished more educational training for local health providers, including providing heath-care knowledge and skills (p Conclusions Health-care services provided by personnel from multiple institutions are as efficient as those from single institutions. Proficiency in the native language and provision of education for local health-care workers are essential for conducting a successful STMM. Our data provide implications for integrating evidence into the deployment of STMMs.

  1. Approaches to English Literacy Teaching in the Central Pacific Republic of Kiribati: Quality Teaching, Educational Aid and Curriculum Reform

    Science.gov (United States)

    Burnett, Greg

    2013-01-01

    English literacy competence in the Central Pacific Republic of Kiribati is considered important for employment, overseas study and general engagement with a globalizing world. It is also considered as a key factor in the current government's response to climate change and sea level rise, enabling skilled relocation of I-Kiribati to other…

  2. Central Wind Forecasting Programs in North America by Regional Transmission Organizations and Electric Utilities: Revised Edition

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, J.; Porter, K.

    2011-03-01

    The report and accompanying table addresses the implementation of central wind power forecasting by electric utilities and regional transmission organizations in North America. The first part of the table focuses on electric utilities and regional transmission organizations that have central wind power forecasting in place; the second part focuses on electric utilities and regional transmission organizations that plan to adopt central wind power forecasting in 2010. This is an update of the December 2009 report, NREL/SR-550-46763.

  3. Authigenic gypsum found in gas hydrate-associated sediments from Hydrate Ridge, the eastern North Pacific

    Institute of Scientific and Technical Information of China (English)

    WANG Jiasheng; Erwin Suess; Dirk Rickert

    2004-01-01

    Characteristic gypsum micro-sphere and granular mass were discovered by binocular microscope in the gas hydrate-associated sediments at cores SO143-221 and SO143/TVG40-2A respectively on Hydrate Ridge of Cascadia margin, the eastern North Pacific. XRD patterns and EPA analyses show both micro-sphere and granular mass of the crystals have the typical peaks and the typical main chemical compositions of gypsum, although their weight percents are slightly less than the others in the non-gas hydrate-associated marine regions. SEM pictures show that the gypsum crystals have clear crystal boundaries, planes, edges and cleavages of gypsum in form either of single crystal or of twin crystals. In view of the fact that there are meanwhile gas hydrate-associated authigenic carbonates and SO42(-rich pore water in the same sediment cores, it could be inferred reasonably that the gypsums formed also authigenically in the gas hydrate-associated environment too, most probably at the interface between the downward advecting sulfate-rich seawater and the below gas hydrate, which spilled calcium during its formation on Hydrate Ridge. The two distinct forms of crystal intergrowth, which are the granular mass of series single gypsum crystals at core SO143/TVG40-2A and the microsphere of gypsum crystals accompanied with detrital components at core SO143-221 respectively, indicate that they precipitated most likely in different interstitial water dynamic environments. So, the distinct authigenic gypsums found in gas hydrate-associated sediments on Hydrate Ridge could also be believed as one of the parameters which could be used to indicate the presence of gas hydrate in an unknown marine sediment cores.

  4. DIFFERENCES AMONG DIFFERENT DATABASES IN THE NUMBER OF TROPICAL CYCLONES FORMING OVER THE WESTERN NORTH PACIFIC

    Institute of Scientific and Technical Information of China (English)

    WU Sheng-an; KONG Hai-jiang; WU hui

    2010-01-01

    As shown in comparisons of the characteristics of inter-annual and inter-decadal variability and periodical changes in the number of tropical cyclones forming over the western North Pacific by three major forecast centers,i.e.China Meteorological Administration (CMA),Regional Specialized Meteorological Center of Tokyo (JMA) and Joint Typhoon Warning Center (JTWC) of Guam,there are the following important points.(1) Climatology of tropical cyclone (TC) or typhoon (TC on the intensity of TS or stronger) shows some difference in tropical cyclone frequency among the centers,which is more notable with TC than with typhoon.Both of them are more at the database of CMA than at those of the other two centers.(2) The difference is too significant to ignore in the inter-annual variability of tropical cyclone frequency between CMA and JTWC,which mainly results from the obvious difference in the inter-annual variability of the number of generated tropical depression (TD) between the two databases.The difference is small in the inter-annual variability of TS formations among all the three databases,and consistence is good between JMA and CMA or JTWC.(3) Though differences are not significant in the periodical variation of TC formations between CMA and JTWC,they are markedly apart in the inter-decadal variability,which is mainly shown by an anti-phase during the 1990s.(4) Non-homogeneity may exist around the late stage of the 1960s in the data of tropical cyclone frequency.

  5. Contributions from DMS and ship emissions to CCN observed over the summertime North Pacific

    Directory of Open Access Journals (Sweden)

    L. Langley

    2010-02-01

    Full Text Available Measurements of cloud condensation nuclei (CCN made over the North Pacific Ocean in July 2002 are analysed with concurrent measurements of aerosol number, mass and composition. Overall the CCN are controlled by the sulphate, including one case that suggests particle nucleation and growth resulting from dimethyl sulphide oxidation that enhanced CCN concentrations. Hourly CCN concentrations are correlated with concentrations of sulphate plus methanesulphonic acid (MSA over the entire study period (r2=0.43 and 0.52 for supersaturations of 0.34% and 0.19%, respectively, and are not well correlated with other organics (r2<0.2. One case study reveals elevated mass and number concentrations of ultrafine and fine organic particles due to regional ship emissions, identified through quadrupole aerosol mass spectrometer (Q-AMS measurements, during which organic mass concentrations are correlated with CCN values (r2=0.39 and 0.46 for supersaturations of 0.19% and 0.34%, respectively. The evolution of the time series and mass distributions of organics, sulphate and MSA over this timeframe indicate that the regional distribution of small, diffuse ship-sourced organic particles act as condensation sites for sulphur species, resulting in a subsequent increase in number concentrations of CCN. We conclude that, where present, direct emissions of anthropogenic organic particles may exert a strong control on marine CCN concentrations once diffused into the marine atmosphere, by acting as condensation sites for biogenic and anthropogenic sulphur species.

  6. Age and Growth of the Dusky Shark, Carcharhinus obscurus, in the Western North Pacific Ocean

    Directory of Open Access Journals (Sweden)

    Shoou-Jeng Joung

    2015-01-01

    Full Text Available Age and growth of the dusky shark, Carcharhinus obscurus, in the western North Pacific Ocean was estimated based on 434 specimens (213 females and 256 males collected between September 2002 and November 2003 at the Nanfanao fish market, in northeastern Taiwan. Sex-specific relationships between body weight (W and total length (TL were estimated as follows: W = 2.03 _ 10-6TL3.216 (n = 209, p < 0.01 for females and W = 8.01 _ 10-6TL2.957 (n = 294, p < 0.01 for males. The relationship between TL and the vertebral centrum radius (R for both sexes _ data was described using the following equation TL = 14.74 + 20.31R (n = 399, p < 0.01. Growth band pairs (including translucent and opaque bands in precaudal vertebrae were determined to form once annually, based on centrum edge analysis and verified by statistical analysis. The maximum number of growth band pairs was 29 for females and 24 for males. The Robertson growth function best fit the observed length-at-age data. Sex-specific growth equations were not significantly different; thus, the combined growth parameters for both sexes were estimated as: asymptotic length (L∞(L∞ = 369.4 cm TL, b = 0.912, growth coefficient (kR = 0.126 yr-1 (n = 385, p < 0.01. Age at maturity was estimated to be 16.6 yrs for females and 15.5 yrs for males.

  7. Low prevalence of avian influenza virus in shorebirds on the Pacific coast of North America

    Science.gov (United States)

    Iverson, Samuel A.; Takekawa, John Y.; Schwarzbach, Steven; Cardona, Carol J.; Warnock, Nils; Bishop, Mary Anne; Schirato, Greg A.; Paroulek, Sara; Ackerman, Joshua T.; Ip, Hon; Boyce, Walter M.

    2008-01-01

    The emergence of highly pathogenic avian influenza (HPAI) H5N1 has elevated concerns about wild birds as virus hosts; however, little is known about the ecological and epidemiological factors of transmission by shorebirds. Here we summarize results for 2,773 shorebirds that were live-trapped on the Pacific coast of the United States during 2006-2007 and tested for avian influenza virus using real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and virus isolation. As was the case throughout North America, HPAI H5N1 was not detected in shorebirds during this interval. Contrary to other wild bird groups, most notably waterfowl, the prevalence of even low pathogenicity virus among shorebirds in our study areas in California, Washington, and Alaska was extremely low (0.5%). Virus was detected by RT-PCR from four different species, including, Dunlin (Calidris alpina; N = 3), Western Sandpiper (C. mauri; N = 8), Long-billed Dowitcher (Limnodromus scolopaceus; N = 1), and American Avocet (Recurvirostra americana; N = 1), with the detections in the latter three constituting the first published records for these birds. Based on studies in the eastern United States, we expected, but did not detect (H1 = 1.6, P = 0.21) elevated avian influenza prevalence among shorebirds during spring migration. Diagnostic tests, which were designed to evaluate testing and sampling methods, indicated poor functioning of traditional virus isolation methods and no improvement in detection likelihood by collecting oropharyngeal swabs in addition to cloacal swab samples for low pathogenicity viruses (Z1 = 0.7, P = 0.48).

  8. Contributions from DMS and ship emissions to CCN observed over the summertime North Pacific

    Directory of Open Access Journals (Sweden)

    L. Phinney

    2009-01-01

    Full Text Available Measurements of cloud condensation nuclei (CCN made over the remote North Pacific Ocean in July 2002 are analysed with concurrent measurements of aerosol number, mass and composition. Overall the CCN are controlled by the sulphate, including one case of particle nucleation and growth resulting from dimethyl sulphide oxidation that enhanced CCN concentrations. Hourly CCN concentrations are correlated with concentrations of sulphate plus methanesulphonic acid (MSA over the entire study period (r2=0.43 and 0.52 for supersaturations of 0.34 and 0.19%, respectively, and are not well correlated with other organics (r2<0.2. One case study reveals elevated mass and number concentrations of ultrafine and fine organic particles due to regional ship emissions, during which organic mass concentrations (see Fig. 2. In Fig. 7c, the 80–90 nm particle concentrations are correlated with CCN values (r2=0.39 and 0.46 for supersaturations of 0.19 and 0.34%, respectively. The evolution of the time series and mass distributions of organics, sulphate and MSA over this timeframe indicate that the regional distribution of small, diffuse ship-sourced organic particles act as condensation sites for sulphur species, resulting in a subsequent increase in number concentrations of CCN. Direct emissions of organic particles may exert a strong control on marine CCN concentrations once diffused into the marine atmosphere by acting as condensation sites for biogenic and anthropogenic sulphur species.

  9. A preliminary study on thermoluminescence characteristics of sediments from the North Pacific

    Institute of Scientific and Technical Information of China (English)

    L(U) Huahua; SHI Xuefa; WU Yonghua; YANG Gang; WEI Jianwei; REN Xiangwen

    2007-01-01

    Thirty-eight surficial deposit samples were collected from the equatorial North Pacific, and the natural thermoluminescence (TL) characteristics of both bulk and clay fraction samples (<2 μm fractions) were studied by the FJ427-A1 automatic TL Dosimeter for the first time. With the measurements of clay mineral composition, element composition by XRD and ICP, the correlations between TL intensity and sedimentary environment proxies were analyzed, such as water depth, ratio of FeO to Fe2O3 contents, LOI, and major clay mineral concentration, and it was found the bulk sample's TL signal was stronger than the clay ones. Usually, increase in the clay components may result in the decrease of TL intensity. From the shape of TL curves, the pelagic sediments can be divided into two groups: the majority group has two glow peaks, in general, the first peak is broad and flat, but the second narrow and sharp; the minority group only has a single peak because the first is absent. The peak centers of TL curves are almost fixed, falling in the temperature sections 230~260 and 390~405 ℃ respectively. Lorentz model packed in the Origin 7.5 was chosen to deal with the TL curves. From the processing results, three parameters (H, C and A), corresponding to the height, center, and kurtosis of TL curve, were obtained to describe the curve characteristics. The correlations between TL curve parameters and sedimentary environment proxies were also calculated. On the basis of the above work, the relationship between TL characteristics and sediment type, mineral composition, sedimentary environment of surface sediments was discussed in the study area, and a conclusion is: sediments from the environment of shallower water, higher organic contents and weaker reductivity have stronger TL signals.

  10. 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.

  11. Caldera formation and varied eruption styles on North Pacific seamounts: the clastic lithofacies record

    Science.gov (United States)

    Portner, Ryan A.; Clague, Dave A.; Paduan, Jennifer B.

    2014-08-01

    Detailed examination of volcaniclastic and sedimentary rocks collected from the Taney (30 Ma), President Jackson (4 Ma), Vance (3 Ma) and Alarcon (2 Ma) near-ridge seamount chains of the North Pacific reveals seven clastic lithofacies that record various modes of eruption, magma fragmentation, and particle dispersal. Lithofacies are distinguished by differences in lithology, bedding habit, compositional heterogeneity, and relationship to volcanic landforms. Breccia lithofacies were produced through mechanical fragmentation during caldera collapse (polymict) or effusive eruptions onto steep slopes (monomict). Rare globular lapilli mudstone lithofacies contain clasts with morphologies formed by magma-sediment mingling processes (peperite). Seamount summit pyroclastic deposits include proximal lapilli tuff with vesicular pyroclasts, and more distal limu o Pele tuff lithofacies. Much finer-grained hydrothermal mudstone/tuff lithofacies occurs around caldera rims and contains greenschist minerals, hydrothermal clays and basaltic ash that record subsurface phreatomagmatic fragmentation processes. Very fine-grained ash is transported to distal regions by oceanic currents and hydrothermal plumes, and is a component of the regional pelagic sediment budget. Pyroclastic lithofacies only occur on seamount summits suggesting formation during the latter stages of seamount evolution. As a seamount drifts away from an adjacent ridge axis and associated heat source, its magma supply is reduced allowing for magmatic gas buildup and mild explosive eruptions. During this stage, the diminished melt supply under the seamount is unable to fully compensate for extension along the ridge axis and vertical seamount growth. Lateral intrusion into spreading-related structures in this stage causes magma withdrawal and caldera formation. Formation of caldera ring faults also promotes seawater ingress into subseafloor hydrothermal cells, which interact with magma conduits causing phreatomagmatic

  12. The characteristic differences of tropical cyclones forming over the western North Pacific and the South China Sea

    Institute of Scientific and Technical Information of China (English)

    YUAN Jinnan; WANG Dongxiao; LIU Chunxia; HUANG Jian; HUANG Huijun

    2007-01-01

    The best track dataset of tropical cyclones in the western North Pacific (WNP) and the South China Sea (SCS) from 1977 to 2005 during the satellite era, the NCEP/NCAR reanalysis dataset and the extended reconstructed sea surface temperature dataset are employed in this study. The main climatological characteristics of tropical cyclone formation over the WNP and the SCS are compared. It is found that there is obviously different for the locations of tropical cyclone origins, achieving the lowest central pressure and termination points between over the WNP and over the SCS. The annual number of tropical cyclones forming over the SCS is obviously less than over the WNP, and there is a significant negative correlation with the correlation coefficient being - 0.36 at the 5% significance level between over the WNP and over the SCS. The mean speed of tropical cyclone moving is 6.5 m/s over the WNP and 4.6 m/s over the SCS. The mean lowest central pressure of tropical cyclones is obviously weaker over the SCS than over the WNP. The tropical cyclone days per year, mean total distance and total displacement of tropical cyclone traveled over the WNP are all obviously longer than those over the SCS. Tropical cyclone may intensify to Saffir - Simpson hurricane scale 5 over the WNP, but no tropical cyclone can intensify to Saffir - Simpson hurricane scale 3 over the SCS. The changing ranges of the radii (R15,R16) of the 15.4 m/s winds them and the 25.7 m/s winds over the WNP are obviously wider than those over the SCS,and the median values of the radii over the WNP are also larger than those over the SCS. For the same intensity of tropical cyclones, both radii have larger medians over the WNP than over the SCS. The correlations of annual mean tropical cyclone size parameters between over the WNP and over the SCS are not significant. At the same time, the asymmetric radii of tropical cyclones over the WNP are different from those over the SCS.

  13. Surface-Wind Anomalies in North-Atlantic and North Pacific from SSM/I Observations: Influence on Temperature of Adjoining Land Regions

    Science.gov (United States)

    Otterman, Joseph; Atlas, R.; Ingraham, J.; Ardizzone, J.; Starr, D.; Terry, J.

    1998-01-01

    Surface winds over the oceans are derived from Special Sensor Microwave Imager (SSM/I) measurements, assigning direction by Variational Analysis Method (VAM). Validations by comparison with other measurements indicate highly-satisfactory data quality. Providing global coverage from 1988, the dataset is a convenient source for surface-wind climatology. In this study, the interannual variability of zonal winds is analyzed concentrating on the westerlies in North Atlantic and North Pacific, above 30 N. Interannual differences in the westerlies exceeding 10 m sec (exp -1) are observed over large regions, often accompanied by changes of the same magnitude in the easterlies below 30 N. We concentrate on February/March, since elevated temperatures, by advancing snow-melt, can produce early spring. The extremely strong westerlies in 1997 observed in these months over North Atlantic (and also North Pacific) apparently contributed to large surface-temperature anomalies in western Europe, on the order of +3 C above the climatic monthly average for England and France. At these latitudes strong positive anomalies extended in a ring around the globe. We formulated an Index of South westerlies for the North Atlantic, which can serve as an indicator for day-by-day advection effects into Europe. In comparing 1997 and 1998 with the previous years, we establish significant correlations with the temperature anomalies (one to five days later, depending on the region, and on the season). This variability of the ocean-surface winds and of the temperature anomalies on land may be related to the El Nino/La Nina oscillations. Such large temperature fluctuations over large areas, whatever the cause, can be regarded as noise in attempts to assess long-term trends in global temperature.

  14. [Nesting habitat characterization for Amazona oratrix (Psittaciformes: Psittacidae) in the Central Pacific, Mexico].

    Science.gov (United States)

    Monterrubio-Rico, Tiberio C; Álvarez-Jara, Margarito; Tellez-Garcia, Loreno; Tena-Morelos, Carlos

    2014-09-01

    The nesting requirements of the Yellow-headed Parrot (Amazona oratrix) are poorly understood, despite their broad historical distribution, high demand for pet trade and current endangered status. Information concerning their nesting requirements is required in order to design specific restoration and conser- vation actions. To assess this, we studied their nesting ecology in the Central Pacific, Michoacan, Mexico during a ten year period. The analyzed variables ranged from local scale nest site characteristics such as nesting tree species, dimensions, geographic positions, diet and nesting forest patches structure, to large scale features such as vegetation use and climatic variables associated to the nesting tree distributions by an ecological niche model using Maxent. We also evaluated the parrot tolerance to land management regimes, and compared the Pacific nest trees with 18 nest trees recorded in an intensively managed private ranch in Tamaulipas, Gulf of Mexico. Parrots nested in tall trees with canopy level cavities in 92 nest-trees recorded from 11 tree species. The 72.8% of nesting occurred in trees of Astronium graveolens, and Enterolobium cyclocarpum which qualified as key- stone trees. The forests where the parrots nested, presented a maximum of 54 tree species, 50% of which were identified as food source; besides, these areas also had a high abundance of trees used as food supply. The lowest number of tree species and trees to forage occurred in an active cattle ranch, whereas the highest species rich- ness was observed in areas with natural recovery. The nesting cavity entrance height from above ground of the Pacific nesting trees resulted higher than those found in the Gulf of Mexico. We hypothesize that the differences may be attributed to Parrot behavioral differences adapting to differential poaching pressure and cavity avail- ability. Nesting trees were found in six vegetation types; however the parrots preferred conserved and riparian semi

  15. Carbon dioxide, temperature, salinity and other variables collected via time series monitoring from MOORINGS in the North Pacific Ocean from 2008-11-11 to 2010-09-01 (NODC Accession 0100066)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0100066 includes chemical, physical, time series and underway - surface data collected from MOORINGS in the North Pacific Ocean and South Pacific...

  16. Carbon dioxide, temperature, salinity and other variables collected via time series monitoring from MOORINGS in the North Pacific Ocean from 2010-01-17 to 2011-03-05 (NODC Accession 0100067)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0100067 includes chemical, physical, time series and underway - surface data collected from MOORINGS in the North Pacific Ocean and South Pacific...

  17. Carbon dioxide, temperature, salinity and other variables collected via time series monitoring from MOORINGS in the North Pacific Ocean from 2004-12-19 to 2007-07-30 (NODC Accession 0100073)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0100073 includes chemical, physical, time series and underway - surface data collected from MOORINGS in the North Pacific Ocean and South Pacific...

  18. Carbon dioxide, temperature, salinity and other variables collected via time series monitoring from MOORINGS in the North Pacific Ocean from 2007-02-18 to 2007-10-03 (NODC Accession 0100070)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0100070 includes chemical, physical, time series and underway - surface data collected from MOORINGS in the North Pacific Ocean and South Pacific...

  19. Carbon dioxide, temperature, salinity and other variables collected via time series monitoring from MOORINGS in the North Pacific Ocean from 2005-12-01 to 2008-05-30 (NODC Accession 0100069)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0100069 includes chemical, physical, time series and underway - surface data collected from MOORINGS in the North Pacific Ocean and South Pacific...

  20. Carbon dioxide, temperature, salinity and other variables collected via time series monitoring from MOORINGS in the North Pacific Ocean from 1998-06-22 to 2004-11-23 (NODC Accession 0100079)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0100079 includes chemical, time series and underway - surface data collected from MOORINGS in the North Pacific Ocean and South Pacific Ocean from...

  1. Temperature profile and water depth data collected from AMERICAN RESERVIST using BT and XBT casts in the North Pacific Ocean from 20 January 1974 to 29 September 1977 (NODC Accession 8900287)

    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 AMERICAN RESERVIST in the North Pacific Ocean and TOGA Area - Pacific Ocean....

  2. Temperature profile and water depth data collected from BAINBRIDGE using BT and XBT casts in the North Pacific Ocean from 28 June 1976 to 31 August 1989 (NODC Accession 8900257)

    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 BAINBRIDGE in the North Pacific Ocean and TOGA Area - Pacific Ocean. Data...

  3. Temperature profile and water depth data collected from BAINBRIDGE using BT and XBT casts in the North Pacific Ocean from 03 July 1975 to 31 October 1977 (NODC Accession 8900230)

    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 BAINBRIDGE in the North Pacific Ocean and TOGA Area - Pacific Ocean. Data...

  4. Temperature profile and water depth data collected from AVON and other platforms using BT and XBT casts in the North Pacific Ocean from 08 April 1975 to 30 November 1989 (NODC Accession 8900300)

    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 AVON and other platforms in the North Pacific Ocean and TOGA Area - Pacific...

  5. Predicting connectivity of green turtles at Palmyra Atoll, central Pacific: a focus on mtDNA and dispersal modelling

    Science.gov (United States)

    Naro-Maciel, Eugenia; Gaughran, Stephen J.; Putman, Nathan F.; Amato, George; Arengo, Felicity; Dutton, Peter H.; McFadden, Katherine W.; Vintinner, Erin C.; Sterling, Eleanor J.

    2014-01-01

    Population connectivity and spatial distribution are fundamentally related to ecology, evolution and behaviour. Here, we combined powerful genetic analysis with simulations of particle dispersal in a high-resolution ocean circulation model to investigate the distribution of green turtles foraging at the remote Palmyra Atoll National Wildlife Refuge, central Pacific. We analysed mitochondrial sequences from turtles (n = 349) collected there over 5 years (2008–2012). Genetic analysis assigned natal origins almost exclusively (approx. 97%) to the West Central and South Central Pacific combined Regional Management Units. Further, our modelling results indicated that turtles could potentially drift from rookeries to Palmyra Atoll via surface currents along a near-Equatorial swathe traversing the Pacific. Comparing findings from genetics and modelling highlighted the complex impacts of ocean currents and behaviour on natal origins. Although the Palmyra feeding ground was highly differentiated genetically from others in the Indo-Pacific, there was no significant differentiation among years, sexes or stage-classes at the Refuge. Understanding the distribution of this foraging population advances knowledge of green turtles and contributes to effective conservation planning for this threatened species.

  6. Central Gulf of Alaska Rockfish Permit Program

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The North Pacific Fishery Management Council adopted the Central Gulf of Alaska Rockfish Program (Rockfish Program) on June 14, 2010, to replace the expiring Pilot...

  7. The Structure of Genetic Diversity in Eelgrass (Zostera marina L.) along the North Pacific and Bering Sea Coasts of Alaska

    Science.gov (United States)

    Talbot, Sandra; Sage, Kevin; Rearick, Jolene; Fowler, Megan C.; Muñiz-Salazar, Raquel; Baibak, Bethany; Wyllie-Echeverria, Sandy; Cabello-Pasini, Alehandro; Ward, David H.

    2016-01-01

    Eelgrass (Zostera marina) populations occupying coastal waters of Alaska are separated by a peninsula and island archipelago into two Large Marine Ecosystems (LMEs). From populations in both LMEs, we characterize genetic diversity, population structure, and polarity in gene flow using nuclear microsatellite fragment and chloroplast and nuclear sequence data. An inverse relationship between genetic diversity and latitude was observed (heterozygosity: R2 = 0.738, P genetic partitioning across most sampling sites (θ = 0.302, P Genetic data failed to support recent proposals that multiple Zostera species (i.e. Z. japonica and Z. angustifolia) are codistributed with Z. marina in Alaska. Comparative analyses also failed to support the hypothesis that eelgrass populations in the North Atlantic derived from eelgrass retained in northeastern Pacific Last Glacial Maximum refugia. These data suggest northeastern Pacific populations are derived from populations expanding northward from temperate populations following climate amelioration at the terminus of the last Pleistocene glaciation.

  8. Modern modes of provenance and dispersal of terrigenous sediments in the North Pacific and Bering Sea: implications and perspectives for palaeoenvironmental reconstructions

    Science.gov (United States)

    Wang, Rong; Biskaborn, Boris K.; Ramisch, Arne; Ren, Jian; Zhang, Yongzhan; Gersonde, Rainer; Diekmann, Bernhard

    2016-08-01

    During expedition 202 aboard the RV Sonne in 2009, 39 seafloor surface sediment sites were sampled over a wide sector of the North Pacific and adjoining Bering Sea. The data served to infer land-ocean linkages of terrigenous sediment supply in terms of major sources and modes of sediment transport within an over-regional context. This is based on an integrated approach dealing with grain-size analysis, bulk mineralogy and clay mineralogy in combination with statistical data evaluation (end-member modelling of grain-size data, fuzzy cluster analysis of mineralogical data). The findings on clay mineralogy served to update those of earlier work extracted from the literature. Today, two processes of terrigenous sediment supply prevail in the study area: far-distance aeolian sediment supply to the pelagic North Pacific, and hemipelagic sediment dispersal from nearby land sources via ocean currents along the continental margins and island arcs. Aeolian particles show the finest grain sizes (clay and fine silt), whereas hemipelagic sediments have high abundances of coarse silt. Exposed sites on seamounts and the continental slope are partly swept by strong currents, leading to residual enrichment of fine sand. Four sediment sources can be distinguished on the basis of distinct index minerals revealed by statistical data analysis: dust plumes from central Asia (quartz, illite), altered materials from the volcanic regions of Kamchatka and the Aleutian Arc (smectite), detritus from the Alaskan Cordillera (chlorite, hornblende), and fluvial detritus from far-eastern Siberia and the Alaska mainland (quartz, feldspar, illite). These findings confirm those of former studies but considerably expand the geographic range of this suite of proxies as far south as 39°N in the open North Pacific. The present integrated methodological approach proved useful in identifying the major modern processes of terrigenous sediment supply to the study region. This aspect deserves attention in

  9. Plate tectonic reconstructions and paleogeographic maps of the central and North Atlantic oceans

    OpenAIRE

    Sibuet, Jean-Claude; Rouzo, Stephane; Srivastava, Shiri

    2012-01-01

    We have established a new plate kinematic model of the central and North Atlantic oceans between North America, Africa, Meseta, Iberia, Flemish Cap, and Galicia Bank from Late Triassic to Late Cretaceous to better understand the nature and timing of rifting of Nova Scotia and Morocco conjugate continental margins since Late Triassic. The maps of salt distributions at the Sinemurian-Pliensbachian limit (190 Ma; after salt deposition) and in middle Bajocian (170 Ma) show that an area of the Nov...

  10. 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...

  11. 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 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 — NODC Accession 0108082 includes chemical, discrete sample, physical and profile data collected from SOUTHERN SURVEYOR in the North Pacific Ocean and South Pacific...

  12. 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...

  13. 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...

  14. 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 1999-11-21 to 1999-12-27 (NODC Accession 0112351)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0112351 includes biological, chemical, discrete sample, physical and profile data collected from MIRAI in the North Pacific Ocean and South Pacific...

  15. 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...

  16. 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...

  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 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...

  18. 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...

  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 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...

  20. 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...

  1. 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...

  2. 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...

  3. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and Calcium collected from discrete sample and profile observations using CTD, bottle and other instruments from the 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 MILLER FREEMAN in the North Pacific Ocean and South Pacific...

  4. 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...

  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 MOORINGS in the North Pacific Ocean and South Pacific Ocean from 2004-05-23 to 2011-09-01 (NODC Accession 0100077)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0100077 includes chemical, physical and time series data collected from MOORINGS in the North Pacific Ocean and South Pacific Ocean from 2004-05-23...

  6. 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...

  7. Inter-annual dynamics of abyssal polychaete communities in the North East Pacific and North East Atlantic—A family-level study

    Science.gov (United States)

    Laguionie-Marchais, C.; Billett, D. S. M.; Paterson, G. L. D.; Ruhl, H. A.; Soto, E. H.; Smith, K. L., Jr.; Thatje, S.

    2013-05-01

    Characterising how deep-sea communities change on contemporary time-scales and understanding underlying ecosystem processes has become important under changing climate and the rise in the exploitation of deep-sea resources. However, little is known about these dynamics and processes. Long-term observations from which inter-annual variations can be detected are scarce in the deep sea. This study examines inter-annual changes in density, family richness and evenness, family and functional group rank abundance distributions of infaunal polychaetes at two abyssal stations in the North East Pacific (Station M, 1991 to 2005) and in the North East Atlantic (Porcupine Abyssal Plain, 1991 to 1999). The two long-term data sets were used to investigate not only if polychaete community structure and composition varied at inter-annual scales in terms of diversity and rank abundance distributions but also if any changes were related to previous observations in megafauna and environmental factors at each locality. The polychaete community structure at each locality was analysed using univariate statistics as well as multivariate ordination techniques based on Bray-Curtis similarity of the yearly family density. Sub-surface deposit feeders, such as Paraonidae, dominated the North East Pacific, whereas surface deposit feeders, such as Cirratulidae, dominated the North East Atlantic. Both stations showed inter-annual variations in density, family evenness and rank abundance distributions. The greatest changes occurred in 1998 in both time series when polychaete densities peaked, and switches in the rank abundance of the most abundant families and functional groups took place. Inter-annual variations in the polychaete community were correlated with a limited number of holothurian species changes, but no correlation was found with particulate organic matter flux or climate indices. Ecological and environmental factors behind the family-level changes remain elusive. Overall, changes in

  8. Interdecadal changes on the seasonal prediction of the western North Pacific summer climate around the late 1970s and early 1990s

    Science.gov (United States)

    Li, Chaofan; Lu, Riyu; Dong, Buwen

    2016-04-01

    Identifying predictability and the corresponding sources for the western North Pacific (WNP) summer climate in the case of non-stationary teleconnections during recent decades benefits for further improvements of long-range prediction on the WNP and East Asian summers. In the past few decades, pronounced increases on the summer sea surface temperature (SST) and associated interannual variability are observed over the tropical Indian Ocean and eastern Pacific around the late 1970s and over the Maritime Continent and western-central Pacific around the early 1990s. These increases are associated with significant enhancements of the interannual variability for the lower-tropospheric wind over the WNP. In this study, we further assess interdecadal changes on the seasonal prediction of the WNP summer anomalies, using May-start retrospective forecasts from the ENSEMBLES multi-model project in the period 1960-2005. It is found that prediction of the WNP summer anomalies exhibits an interdecadal shift with higher prediction skills since the late 1970s, particularly after the early 1990s. Improvements of the prediction skills for SSTs after the late 1970s are mainly found around tropical Indian Ocean and the WNP. The better prediction of the WNP after the late 1970s may arise mainly from the improvement of the SST prediction around the tropical eastern Indian Ocean. The close teleconnections between the tropical eastern Indian Ocean and WNP summer variability work both in the model predictions and observations. After the early 1990s, on the other hand, the improvements are detected mainly around the South China Sea and Philippines for the lower-tropospheric zonal wind and precipitation anomalies, associating with a better description of the SST anomalies around the Maritime Continent. A dipole SST pattern over the Maritime Continent and the central equatorial Pacific Ocean is closely related to the WNP summer anomalies after the early 1990s. This teleconnection mode is quite

  9. Marketing Remote Sensing Data for North Pacific Fisheries Development and Management

    Science.gov (United States)

    1995-01-01

    Fish poaching, drug trafficking, ocean dumping, and other illegal activities are important problems on the high seas and in national economic zones. The primary thrust of the EOCAP II project, "Marketing Remote Sensing Data for North Pacific Fisheries Development and Management", was to use space-based sensors to improve the effectiveness of marine monitoring, control, and surveillance (MCS). Our initial objectives were to concentrate on the development of MCS tools using Advanced Very High Resolution Radiometry (AVHRR) and Synthetic Aperture Radar (SAR) data. Although we have successfully completed development of an initial version of our SAR-based monitoring tool (OmniVision), project activity has resulted in a much broader application of space-based assets to marine applications. Based in part on work commenced within EOCAP II, a new company, Ocean and Coastal Environmental Sensing, Inc. (OCENS), has been launched and the development of several new software products outside of the MCS arena initiated. One of those products, SeaStation, is near completion with a Fall, 1995 release date. Equity investment in OCENS now totals $70,000-with an additional amount being sought in the first round of financing. One of the pre-eminent objectives of EOCAP II is to make contributions to the US economy and job growth through the expansion of commercial uses of remotely sensed data. OCENS and the software products it is introducing into marine and coastal zone markets responds to this primary object*e. EOCAP II funding leveraged the market and technical know-how of OCENS founders into smart products that benefit marine and coastal zone users. Although technical difficulties and geopolitical shifts damaged the commercial feasibility of initial project objectives, the flexibility of the EOCAP II program now permits long-term business success. This in no small part stems from the fact that the EOCAP program recognizes the realities of small and start-up businesses and does not

  10. Evaluating controls on planktonic foraminiferal geochemistry in the Eastern Tropical North Pacific

    Science.gov (United States)

    Gibson, Kelly Ann; Thunell, Robert C.; Machain-Castillo, Maria Luisa; Fehrenbacher, Jennifer; Spero, Howard J.; Wejnert, Kate; Nava-Fernández, Xinantecatl; Tappa, Eric J.

    2016-10-01

    To explore relationships between water column hydrography and foraminiferal geochemistry in the Eastern Tropical North Pacific, we present δ18O and Mg/Ca records from three species of planktonic foraminifera, Globigerinoides ruber, Globigerina bulloides, and Globorotalia menardii, collected from a sediment trap mooring maintained in the Gulf of Tehuantepec from 2006-2012. Differences in δ18O between mixed-layer species G. ruber and G. bulloides and thermocline-dweller G. menardii track seasonal changes in upwelling. The records suggest an increase in upwelling during the peak positive phase of El Niño, and an overall reduction in stratification over the six-year period. For all three species, Mg/Ca ratios are higher than what has been reported in previous studies, and show poor correlations to calcification temperature. We suggest that low pH (7.6-8.0) and [3 2-CO] values (∼70-120 μmol/kg) in the mixed layer contribute to an overall trend of higher Mg/Ca ratios in this region. Laser Ablation Inductively Coupled Mass Spectrometry analyses of G. bulloides with high Mg/Ca ratios (>9 mmol/mol) reveal the presence of a secondary coating of inorganic calcite that has Mg/Ca and Mn/Ca ratios up to an order of magnitude higher than these elemental ratios in the primary calcite, along with elevated Sr/Ca and Ba/Ca ratios. Some of the samples with abnormally high Mg/Ca are found during periods of high primary productivity, suggesting the alteration may be related to changes in carbonate saturation resulting from remineralization of organic matter in oxygen-poor waters in the water column. Although similar shell layering has been observed on fossil foraminifera, this is the first time such alteration has been studied in shells collected from the water column. Our results suggest a role for seawater carbonate chemistry in influencing foraminiferal calcite trace element:calcium ratios prior to deposition on the seafloor, particularly in high-productivity, low

  11. Diversity of cultured photosynthetic flagellates in the North East Pacific and Arctic Oceans in summer

    Science.gov (United States)

    Balzano, S.; Gourvil, P.; Siano, R.; Chanoine, M.; Marie, D.; Lessard, S.; Sarno, D.; Vaulot, D.

    2012-06-01

    During the MALINA cruise (summer 2009) an extensive effort was undertaken to isolate phytoplankton strains from the North East (NE) Pacific Ocean, the Bering Strait, and the Beaufort Sea. Strains were isolated by flow cytometry sorting (FCS) and pipetting before or after phytoplankton enrichment of seawater samples. Strains were isolated both onboard and back in the laboratory and cultured at 4 °C under light/dark conditions. Overall, we isolated and characterised by light microscopy and 18S rRNA gene sequencing 104 strains of photosynthetic flagellates which grouped into 21 genotypes (defined by 99.5% 18S rRNA gene sequence similarity) mainly affiliated to Chlorophyta and Heterokontophyta. The taxon most frequently isolated was an Arctic ecotype of the green algal genus Micromonas (Arctic Micromonas) which was almost the only phytoplankter recovered within picoplankton (≤ 2 μm) size range. Strains of Arctic Micromonas as well as three unidentified strains related to the same genus were identified in further details by sequencing the Internal Transcribed Spacer (ITS) region of the rRNA operon. The MALINA Micromonas strains share identical 18S rRNA and ITS sequences suggesting high genetic homogeneity within Arctic Micromonas. The unidentified strains form a genotype likely belonging to a new genus within the family Mamiellaceae to which Micromonas belongs. Other green algae genotypes from the genera Nephroselmis, Chlamydomonas, Pyramimonas were also isolated whereas Heterokontophyta included Pelagophyceae, Dictyochophyceae and Chrysophyceae. Dictyochophyceae included Pedinellales which could not be identified to the genus level whereas Chrysophyceae comprised Dinobryon faculiferum. Moreover, we isolated Rhodomonas sp. as well as a few Haptophyta and dinoflagellates. We identified the dinoflagellate Woloszynskia cincta by Scanning Electron Microscopy (SEM) and 28S rRNA gene sequencing. Our morphological analyses show that this species possess the diagnostic

  12. Latitudinal distributions of organic nitrogen and organic carbon in marine aerosols over the western North Pacific

    Directory of Open Access Journals (Sweden)

    Y. Miyazaki

    2010-11-01

    Full Text Available Marine aerosol samples were collected over the western North Pacific along the latitudinal transect from 44° N to 10° N in late summer 2008 for measurements of organic nitrogen (ON and organic carbon (OC as well as isotopic ratios of total nitrogen (TN and total carbon (TC. Increased concentrations of methanesulfonic acid (MSA and diethylammonium (DEA+ at 40–44° N and subtropical regions (10–20° N together with averaged satellite chlorophyll a data and 5-day back trajectories suggest a significant influence of marine biological activities on aerosols in these regions. ON exhibited increased concentrations up to 260 ngN m−3 in these marine biologically influenced aerosols. Water-insoluble organic nitrogen (WION was found to be the most abundant nitrogen in the aerosols, accounting for 55 ± 16% of total aerosol nitrogen. In particular, the average WION/ON ratio was as high as 0.93 ± 0.07 at 40–44° N. These results suggest that marine biological sources significantly contributed to ON, a majority of which is composed of water-insoluble fractions in the study region. Analysis of the stable carbon isotopic ratios (δ13C indicated that, on average, marine-derived carbon accounted for ~88 ± 12% of total carbon in the aerosols. In addition, the δ13C increased from −22 to −20‰ when ON/OC ratios increased from 0.15 to 0.35 in marine biologically influenced aerosols. These results clearly show that organic nitrogen is enriched in organic aerosols originated from an oceanic region with high biological productivity, indicating a preferential transfer of nitrogen-containing organic compounds from the sea surface to the marine atmosphere. Both WION concentrations and WION/water-insoluble organic carbon (WIOC ratios showed positive correlations with local wind speeds, suggesting that sea-to-air emissions of ON via sea spray significantly contributes to marine organic aerosols over the

  13. Latitudinal distributions of organic nitrogen and organic carbon in marine aerosols over the western North Pacific

    Directory of Open Access Journals (Sweden)

    Y. Miyazaki

    2011-04-01

    Full Text Available Marine aerosol samples were collected over the western North Pacific along the latitudinal transect from 44° N to 10° N in late summer 2008 for measurements of organic nitrogen (ON and organic carbon (OC as well as isotopic ratios of total nitrogen (TN and total carbon (TC. Increased concentrations of methanesulfonic acid (MSA and diethylammonium (DEA+ at 40–44° N and subtropical regions (10–20° N together with averaged satellite chlorophyll-a data and 5-day back trajectories suggest a significant influence of marine biological activities on aerosols in these regions. ON exhibited increased concentrations up to 260 ngN m−3 in these marine biologically influenced aerosols. Water-insoluble organic nitrogen (WION was found to be the most abundant nitrogen in the aerosols, accounting for 55 ± 16% of total aerosol nitrogen. In particular, the average WION/ON ratio was as high as 0.93 ± 0.07 at 40–44° N. These results suggest that marine biological sources significantly contributed to ON, a majority of which is composed of water-insoluble fractions in the study region. Analysis of the stable carbon isotopic ratios (δ13C indicated that, on average, marine-derived carbon accounted for ~88 ± 12% of total carbon in the aerosols. In addition, the δ13C showed higher values (from −22 to −20‰ when ON/OC ratios increased from 0.15 to 0.35 in marine biologically influenced aerosols. These results clearly show that organic nitrogen is enriched in organic aerosols originated from an oceanic region with high biological productivity, indicating a preferential transfer of nitrogen-containing organic compounds from the sea surface to the marine atmosphere. Both WION concentrations and WION/water-insoluble organic carbon (WIOC ratios tended to increase with increasing local wind speeds, indicating that sea-to-air emissions of ON via sea spray contribute significantly to the marine organic

  14. 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

  15. Physical and chemical effects of ingested plastic debris on short-tailed shearwaters, Puffinus tenuirostris, in the North Pacific Ocean

    OpenAIRE

    Yamashita, Rei; Takada, Hideshige; Fukuwaka, Masa-aki; Watanuki, Yutaka

    2011-01-01

    We investigated the plastics ingested by short-tailed shearwaters, Puffinus tenuirostris, that were accidentally caught during experimental fishing in the North Pacific Ocean in 2003 and 2005. The mean mass of plastics found in the stomach was 0.23 g per bird (n = 99). Plastic mass did not correlate with body weight. Total PCB (sum of 24 congeners) concentrations in the abdominal adipose tissue of 12 birds ranged from 45 to 529 ng/g-lipid. Although total PCBs or higher-chlorinated congeners, ...

  16. Acoustic detection and satellite-tracking leads to discovery of rare concentration of endangered North Pacific right whales

    OpenAIRE

    Wade, Paul; Heide-Jørgensen, Mads Peter; Shelden, Kim; Barlow, Jay; Carretta, James; Durban, John; LeDuc, Rick; Munger, Lisa; Rankin, Shannon; Sauter, Allan; Stinchcomb, Charles

    2006-01-01

    The North Pacific right whale, Eubalaena japonica, is one of the most endangered species of whale in the world. On 10 August 2004, two right whales were located in the Bering Sea using headings to right whale calls provided by directional sonobuoys. A satellite-monitored radio tag attached to one of these whales functioned for 40 days. Over the 40-day period, this whale moved throughout a large part of the southeast Bering Sea shelf, including areas of the outer-shelf where right whales have ...

  17. Os isotope dating and growth hiatuses of Co-rich crust from central Pacific

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Up to now, accurate determination of the growth age and hiatuses of the Co-rich crust is still a difficult work, which constrains the researches on the genesis, growth process, controlling factors, regional tectonics, paleo-oceanographic background, etc. of the Co-rich crust. This paper describes our work in determining the initial growth age of the Co-rich crust to be of the late Cretaceous Campanian Stage (about 75-80 Ma), by selecting the Co-rich crust with clear multi-layer structures in a central Pacific seamount for layer-by-layer sample analysis and using a number of chronological methods, such as Co flux dating, dating by correlation with 187Os/188Os evolution curves of seawater, and stratigraphic divi- sion by calcareous nannofossils. We have also discovered growth hiatuses with different time intervals in the early Paleocene, middle Eocene, late Eocene and early-middle Miocene, respectively. These re- sults have provided an important age background for further researches on the Co-rich crust growth process and the paleo-oceanographic environment evolution thereby revealed in the said region.

  18. Toward a classification of the Central Pacific El Niño

    Science.gov (United States)

    Pascolini-Campbell, M.; Zanchettin, D.; Bothe, O.; Timmreck, C.; Matei, D.; Jungclaus, J. H.; Graf, H.-F.

    2012-09-01

    We investigate the various methods currently available for distinguishing between the Central Pacific (CP) El Niño (or "El Niño Modoki") and the canonical El Niño by considering 10 different methods and 5 sea surface temperature (SST) datasets from 1880 to 2010. Years which are classified as CP El Niños with the greatest convergence between method and SST dataset are considered to provide a more robust identification of these events. The results identify 13 yr which are classified the most consistently as CP events: 1885/1886, 1914/1915, 1940/1941, 1958/1959, 1963/1964, 1968/1969, 1977/1978, 1986/1987, 1991/1992, 2002/2003, 2003/2004, 2004/2005 and 2009/2010. Our findings also indicate the persistence of CP events throughout the time period investigated, inciting the role of multidecadal natural climate variability in generating CP El Niños.

  19. Toward a classification of the Central Pacific El Niño

    Directory of Open Access Journals (Sweden)

    M. Pascolini-Campbell

    2012-09-01

    Full Text Available We investigate the various methods currently available for distinguishing between the Central Pacific (CP El Niño (or "El Niño Modoki" and the canonical El Niño by considering 10 different methods and 5 sea surface temperature (SST datasets from 1880 to 2010. Years which are classified as CP El Niños with the greatest convergence between method and SST dataset are considered to provide a more robust identification of these events. The results identify 13 yr which are classified the most consistently as CP events: 1885/1886, 1914/1915, 1940/1941, 1958/1959, 1963/1964, 1968/1969, 1977/1978, 1986/1987, 1991/1992, 2002/2003, 2003/2004, 2004/2005 and 2009/2010. Our findings also indicate the persistence of CP events throughout the time period investigated, inciting the role of multidecadal natural climate variability in generating CP El Niños.

  20. Effects of the Yakutat terrane collision with North America on the neighboring Pacific plate

    Science.gov (United States)

    Reece, R.; Gulick, S. P.; Christeson, G. L.; Barth, G. A.; van Avendonk, H.

    2011-12-01

    High-resolution bathymetry data show a 30 km N-S trending ridge within the deep-sea Surveyor Fan between the mouths of the Yakutat Sea Valley and Bering Trough in the Gulf of Alaska. The ridge originates in the north, perpendicular to and at the base of the continental slope, coincident with the Transition Fault, the strike-slip boundary between the Yakutat terrane (YAK) and the Pacific plate (PAC). The ridge exhibits greatest relief adjacent to the Transition Fault, and becomes less distinct farther from the shelf edge. Seismic reflection data reveal a sharp basement high beneath the ridge (1.1 sec of relief above "normal" basement in two-way travel time) as well as multiple similarly oriented strike-slip fault segments. The ridge, basement high, and faults are aligned and co-located with an intraplate earthquake swarm on the PAC, which includes four events > 6.5 Mw that occurred from 1987-1992. The swarm is defined by right-lateral strike-slip events, and is collectively called the Gulf of Alaska Shear Zone (GASZ). Based on the extent of historic seismicity, the GASZ extends at least 230 km into the PAC, seemingly ending at the Kodiak-Bowie Seamount Chain. Farther southwest, between the Kodiak-Bowie and Patton-Murray Seamount Chains, there is a large regional bathymetric low with an axis centered along the Aja Fracture Zone, perpendicular to the GASZ and Aleutian Trench. Basement and overlying sediment in the low are irregularly, but pervasively faulted. The GASZ and faulted bathymetric low could represent PAC deformation due to PAC-YAK coupling whereby YAK resistance to subduction is expressed as deformation in the thinner (weaker) PAC crust. The YAK is an allochthonous, basaltic terrane coupled to the PAC that began subducting at a low angle beneath North America (NA) ~25-40 Ma. Due to its 15-25 km thickness, the YAK is resistant to subduction compared to the normal oceanic crust of the PAC. As a result the plates developed differential motion along the

  1. Feedback of 10-20-day intraseasonal oscillations on seasonal mean SST in the tropical Western North Pacific during boreal spring through fall

    Science.gov (United States)

    Wu, Renguang

    2016-09-01

    The present study documents the factors for year-to-year changes in the intensity of 10-20-day intraseasonal oscillations (ISOs) and investigates the feedback of the 10-20-day ISO intensity on seasonal mean sea surface temperature (SST) change in the tropical western North Pacific during boreal spring through fall. An analysis of local correlation reveals a significant negative correlation of the 10-20-day ISO intensity and the seasonal mean SST tendency in the tropical western North Pacific during spring, summer, and fall, suggesting a plausible feedback of the ISO intensity on seasonal mean SST anomaly. The 10-20-day ISO intensity change over the tropical western North Pacific is influenced by El Niño-Southern Oscillation (ENSO) through modulation of vertical shear of zonal winds, lower-level moisture, and upward motion. Due to the phase dependence of location of these ENSO-induced background field changes, the ISO intensity is subject to ENSO influence in different regions during the three seasons. The feedback of the 10-20-day ISO intensity on local seasonal mean SST change in the tropical western North Pacific is demonstrated by separating latent heat flux anomalies into components on different time scales. The ISO-induced latent heat flux anomalies may accumulate in a season and overcome interannual anomalies due to seasonal mean changes. Thus, the ISO-induced surface heat flux change may play an important role in the seasonal mean SST anomaly in the tropical western North Pacific.

  2. Feeding habits of Dall's porpoises ( Phocoenoides dalli) in the subarctic North Pacific and the Bering Sea basin and the impact of predation on mesopelagic micronekton

    Science.gov (United States)

    Ohizumi, Hiroshi; Kuramochi, Toshiaki; Kubodera, Tsunemi; Yoshioka, Motoi; Miyazaki, Nobuyuki

    2003-05-01

    We investigated the stomach contents of Dall's porpoises collected in pelagic waters spanning most of their range in the North Pacific and the Bering Sea. Analysis revealed the porpoises fed mainly on myctophid fishes in the subarctic North Pacific and on gonatid squids as well as myctophid fishes in the Bering Sea. Most of the prey items were mesopelagic micronekton, primarily fishes and squids that migrate vertically to shallower waters at night. Stomach content was greater during twilight hours, suggesting the porpoises foraged actively on myctophids at night in shallower waters. Stomach contents were strongly characterized by local mesopelagic prey fauna, and prey species selectivity was not apparent. The annual consumption by Dall's porpoises was estimated to be 2.0-2.8 million tons, or 4.7-6.5% of the biomass of mesopelagic fishes in the subarctic North Pacific, and may account for approximately 24-33% of the overall mortality of mesopelagic micronekton, especially myctophids. Myctophids are also common, but less important, prey of other subarctic predators. Dall's porpoises are likely the primary consumers of myctophids in the subarctic North Pacific. Since myctophids are the major component of the mesotrophic level, the trophic relationship between myctophids and Dall's porpoises is thought to be an important pathway of mass and energy in the pelagic food web in the subarctic North Pacific.

  3. Organic composition of single and submicron particles in different regions of western North America and the eastern Pacific during INTEX-B 2006

    Directory of Open Access Journals (Sweden)

    D. A. Day

    2009-08-01

    Full Text Available Single particles were collected from an aircraft platform as part of the Intercontinental Chemical Transport Experiment – Phase B (INTEX-B conducted over the eastern Pacific and western North America. Single particle spectra were obtained using scanning transmission X-ray microscopy-near edge X-ray absorption fine structure spectroscopy (STXM-NEXAFS. Bulk submicron particles were also collected and organic functional group and elemental concentrations were quantified with Fourier transform infrared (FTIR spectroscopy and X-ray fluorescence (XRF. Single particle spectra were classified into metaclasses associated with different sources and atmospheric processing. Particles with spectra indicative of secondary organic aerosol production and combustion sources were found at several locations and a range of altitudes. At lower altitudes, particles with spectra resembling soil dust and biomass burning fingerprints were commonly observed. The types of particle spectra most commonly observed aloft were similar to those observed during a previous study over the northwestern Pacific, indicating that long-range transport may have been an important particle source. Single particle spectra provided evidence that condensation and surface-limited oxidation contributed to particle growth. Organic mass (OM concentrations ranged from 1 to 7 μg m−3 and averaged 2.4–4.1 μg m−3. Alkane functional groups were the largest fraction of OM, averaging 1.9–2.1 μg m−3 or 50–76% of OM, followed by alcohol functional groups (0.35–0.39 μg m−3, 9–14%. Organic and elemental concentrations are compared within and among geographical air mass regions: "Pacific" free troposphere, "Continental" free troposphere, "Seattle" metropolitan region, and the California "Central Valley". OM concentrations were highest and most variable in the Central Valley (3.5±2 μg m−3. Oxygen-to-carbon ratios were

  4. A hypothesis and a case-study projection of an influence of MJO modulation on boreal-summer tropical cyclogenesis in a warmer climate with a global non-hydrostatic model: a transition toward the central Pacific?

    Directory of Open Access Journals (Sweden)

    KAZUYOSHI eOOUCHI

    2014-02-01

    Full Text Available The eastward shift of the enhanced activity of tropical cyclone to the central Pacific is a robust projection result for a future warmer climate, and is shared by most of the state-of-the-art climate models. The shift has been argued to originate from the underlying El-Ñino like sea-surface temperature (SST forcing. This study explores the possibility that the change of the activity of the Madden-Julian Oscillation (MJO can be an additional, if not alternative, contributor to the shift, using the dataset of Yamada et al. (2010 from a global non-hydrostatic 14-km grid mesh time-slice experiment for a boreal-summer case. Within the case-study framework, we develop the hypothesis that an eastward shift of the high-activity area of the MJO, as manifested itself as the significant intra-seasonal modulation of the enhanced precipitation, is associated with the increased tropical cyclogenesis potential over the North central Pacific by regulating cyclonic relative vorticity and vertical shear. In contrast, the North Indian Ocean and maritime continent undergo relatively diminished genesis potential. An implication is that uncertainty in the future tropical cyclogenesis in some part of the Pacific and other ocean basins could be reduced if projection of the MJO and its connection with the underlying SST environment can be better understood and constrained by the improvement of climate models.

  5. Observation of the April 2001 Asian Dust Event by Robotic Carbon Biomass Profiling Floats in the Subarctic North Pacific

    Science.gov (United States)

    Bishop, J. K.; Davis, R. E.

    2001-12-01

    My thesis work (Bishop, 1977) with John was to explore the first aspects of particulate matter biogeochemistry using large volume in-situ filtration sampling. The hardware has evolved from a single sampling device to the 12 unit Multiple Unit Large Volume in-situ Filtration System (MULVFS). These samples have been analyzed for an increasingly 'Edmondian' suite of chemical species. The science question John asked me to address was "How does the chemistry, biology and vertical flux of particulate matter vary in space and time? What are the dominant controlling processes?" The question remains central to the understanding of the biologically driven part of ocean's carbon cycle and still is largely unanswered for most of the world's ocean, especially in the upper ocean from the base of the euphotic zone to kilometer depths. A recent milestone for MULVFS sampling was our first winter-time collection of particles from waters of the subarctic Pacific during Feb. 1996. This kilometer deep profile did establish a benchmark for interpretation of changes in particulate matter abundances in subsurface waters in later seasons. At the same time we found abundant large diatoms and a coccolithophore `bloomlet' in the winter-time surface layer. They had vanished when we revisted the site 9 weeks later. The system had moved much faster than we could follow. The international project Argo will deploy several thousand autonomous profiling floats over the next few years to provide an improved view of the climate state of the ocean. The recent 20-fold plus improvement of rates of ocean to satellite data telemetry permits augmentation of the long-lived Argo-style floats with low-power sensors for carbon system components. As a first step, we have developed a prototype robotic autonomous carbon observer capable of performing high frequency (diurnal) observations of the upper kilometer for seasons to years. The aim is to enable improved exploration of the ocean biological carbon pump

  6. Central Tropical Pacific SST and Salinity Variability over the Little Ice Age

    Science.gov (United States)

    Sayani, H. R.; Cobb, K. M.; Khare, A.; Stone, C.; Grothe, P. R.; Chen, T.; Cheng, H.; Lu, Y.; Edwards, R. L.

    2015-12-01

    Anthropogenic trends are difficult to separate from natural variability in the tropical Pacific, where instrumental data coverage is sparse. Of particular interest are variations of climate in the pre-industrial era, but instrumental data from this time period is virtually nonexistent. Corals allow for the investigation of pre-industrial climate variability, but most living coral colonies rarely span more than a century. Fossil corals provide a valuable archive of climate variability over the past millennia [Cobb et al., 2013] and are best suited to the reconstruction of ENSO. For the reconstruction of mean climate, systematic offsets between proxy records from contemporaneous corals translates to large error bars on the resulting reconstructions [e.g. Felis et al., 2003; Pfeiffer et al., 2009]. By building composite paleoclimate records using multiple corals from the Line Islands (2°N - 6°N, 157°W - 162°W), we quantify mean climate state and climate variability in the central tropical Pacific (CTP) during the Little Ice Age (LIA). We compare paired d18O and Sr/Ca records from Line Island fossil corals to a large collection of modern coral d18O and Sr/Ca records from the same islands to estimate SST and salinity changes from the LIA to the late 20th century. Taken together, Sr/Ca records from three Palmyra Atoll fossil corals spanning 1630-1703CE suggest CTP temperatures may have been 1.7±0.9˚C cooler during much of the 17th century. Reconstructed seawater d18O values are indicative of drier conditions at Palmyra, consistent with a southward shift of the ITCZ during the LIA documented in sediments from the Line Islands [Sachs et al., 2009]. We compare the results from seven LIA-dated fossil corals from nearby Christmas Island (Kiritimati; 2˚N, 157˚W) to the results obtained from Palmyra, enabling us to resolve potential shifts in the meridional gradients of SST and hydrology in this region during the LIA. References:Cobb, K. M., et al. (2013) Science. doi

  7. Weights, hematology and serum chemistry of free-ranging brown boobies (Sula leucogaster) in Johnston Atoll, Central Pacific

    Science.gov (United States)

    Work, T.M.

    1999-01-01

    Hematologic and serum chemistry values are reported for 105 brown boobies (Sula leucogaster) from Johnston Atoll, Central Pacific. Hematocrit, estimated total plasma solids, total and differential white cell counts, serum glucose, calcium, phosphorus, uric acid, total protein, albumin, globulin, aspartate aminotransferase, and creatinine phosphokinase were analyzed. Hematologic and serum chemistry values varied with age and sex. Values were compared with those of red-footed boobies and other tropical and temperate marine pelecaniforms.

  8. Postrelease survival, vertical and horizontal movements, and thermal habitats of five species of pelagic sharks in the central Pacific Ocean

    OpenAIRE

    Musyl, Michael K.; Brill, Richard W; Curran, Daniel S.; Fragoso, Nuno M.; McNaughton, Lianne M.; Nielsen, Anders; Kikkawa, Bert S.; Moyes, Christopher D

    2011-01-01

    From 2001 to 2006, 71 pop-up satellite archival tags (PSATs) were deployed on five species of pelagic shark (blue shark [Prionace glauca]; shortfin mako [Isurus oxyrinchus]; silky shark [Carcharhinus falciformis]; oceanic whitetip shark [C. longimanus]; and bigeye thresher [Alopias superciliosus]) in the central Pacific Ocean to determine species-specific movement patterns and survival rates after release from longline fishing gear. Only a single postrelease mortality could be unequivoc...

  9. Abyssal fauna of the UK-1 polymetallic nodule exploration claim, Clarion-Clipperton Zone, central Pacific Ocean: Echinodermata

    OpenAIRE

    Glover, Adrian G.; Wiklund,Helena; Rabone, Muriel; Amon, Diva J; Smith, Craig R.; O'Hara,Tim; Mah, Christopher L.; Dahlgren, Thomas G

    2016-01-01

    Abstract We present data from a DNA taxonomy register of the abyssal benthic Echinodermata collected as part of the Abyssal Baseline (ABYSSLINE) environmental survey cruise ‘AB01’ to the UK Seabed Resources Ltd (UKSRL) polymetallic-nodule exploration claim ‘UK-1’ in the eastern Clarion-Clipperton Zone (CCZ), central Pacific Ocean abyssal plain. Morphological and genetic data are presented for 17 species (4 Asteroidea , 4 Crinoidea , 2 Holothuroidea and 7 Ophiuroidea ) identified by a combinat...

  10. DIGITAL GEOLOGIC MAP OF SHERMAN QUADRANGLE, NORTH CENTRAL TEXAS (CD-ROM)

    Science.gov (United States)

    This compact disc contains digital data sets of the surficial geology and geologic faults for the 1:250,000-scale Sherman quadrangle, North Central Texas, and can be used to make geologic maps, and determine approximate areas and locations of various geologic units. The source d...

  11. A Year of Transition: North Central Regional Center for Rural Development Annual Report 2009

    Science.gov (United States)

    North Central Regional Center for Rural Development, 2009

    2009-01-01

    The North Central Regional Center for Rural Development (NCRCRD) is one of four centers in the United States that work to improve opportunities and quality of life in rural communities. With funding from the USDA National Institute of Food and Agriculture and the land-grant universities in its 12-state region, the NCRCRD engages Extension…

  12. North Central Climate Science Center--science agenda 2012-2017

    Science.gov (United States)

    Morisette, Jeffrey T.

    2012-01-01

    The information presented here provides the five-year science agenda for the North Central Climate Science Center. It is meant to be a high-level guide that describes the spatial context of the center, the primary partners and stakeholders, and the strategic framework the center will use in applying climate science to inform management.

  13. Open-Country Poverty in a Relatively Affluent Area - The East North Central States.

    Science.gov (United States)

    Fitzwilliams, Jeanette

    Poverty among open-country households in the East North Central States (11%) was slightly above the incidence found among U.S. whites in general. Incidence of poverty was greatest among the aged, disabled, and small farmers of all ages who made farming their major source of earnings. Of the respondent households in this 1967 survey, 87% had…

  14. The impact of cooling ponds in North Central Texas on dairy farm performance

    NARCIS (Netherlands)

    Tomaszewski, M.A.; Haan, de M.H.A.; Thompson, J.A.; Jordan, E.R.

    2005-01-01

    The objective of this study was to determine whether measurable differences existed between farms with and without cooling ponds. Data from Dairy Herd Improvement records for 1999 through 2002 were obtained on 42 herds located in North Central Texas. Nineteen herds had installed cooling ponds, where

  15. Analysis and prognosis of tropical cyclone genesis over the western North Pacific on the background of global warming

    Institute of Scientific and Technical Information of China (English)

    LI Yongping; WANG Xiaofeng; YU Runling; QIN Zenghao

    2007-01-01

    As revealed by the observational study, there are more tropical cyclones generated over the western North Pacific from the early 1950s to the early 1970s in the 20th century and less tropical cyclones from the mid-1970s to the present. The decadal change of tropical cyclones activities are closely related to the decadal changes of atmospheric general circulation in the troposphere, which provide favorable or unfavorable conditions for the formation of tropical cyclone. Furthermore, based on the simulation of corresponding atmospheric general circulation from a coupled climate model under the schemes of Intergovernmental Panel on Climate Change (IPCC) special report on emission scenarios (SRES) A2 and B2 emissions scenarios an outlook on the tropical cyclone frequency generated over the western North Pacific in the coming half century is presented. It is indicated that in response to the global climate change the general circulation of atmosphere would become unfavorable for the formation of tropical cyclone as a whole and the frequency of tropical cyclones formation would likely decrease by 5% within the next half century, although more tropical cyclones would appear during a short period in it.

  16. STUDY ON THE CHARACTERISTICS OF TROPICAL CYCLONES ACTIVITY OVER THE WESTERN NORTH PACIFIC IN 2004 AND THE CAUSATION

    Institute of Scientific and Technical Information of China (English)

    DONG Mei-ying; ZHENG Pei-qun; XUE Gen-yuan

    2007-01-01

    In this paper, we summarized the characteristics of tropical cyclones (TC) activity over the western North Pacific in 2004 and analyzed their causation. Compared with the normal, the annual frequency of TC in 2004 was slightly higher, tropical cyclones in 2004 had a longer life span and occurred in a concentrated period, the source of TC were situated eastward; in all tracks of TC, the recurvature tracks took up larger proportion, the landfall regions of TC were located northward, which concentrated from East China to Japan. The primary causes were revealed as follows. Firstly, the intensity and area of the western North Pacific subtropical high was stronger and larger than usual respectively, and its ridge was frequently in the form of cells and stretched northwestward. Secondly, the convergence of intertropical convergence zone (ITCZ) was reinforced and the convergence zone moved more eastward than average. Thirdly, the meridionality of the westerlies was larger than average and the cell-shaped ridge formed a saddle region,which is in favor of TC northward motion and recurature.

  17. 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 (pclimate variability can play in ocean biology.

  18. Sulphur compounds, methane, and phytoplankton: interactions along a north-south transit in the western Pacific Ocean

    Science.gov (United States)

    Zindler, C.; Bracher, A.; Marandino, C. A.; Taylor, B.; Torrecilla, E.; Kock, A.; Bange, H. W.

    2012-10-01

    Here we present results of the first comprehensive study of sulphur compounds and methane in the oligotrophic tropical West Pacific Ocean. The concentrations of dimethylsuphide (DMS), dimethylsulphoniopropionate (DMSP), dimethylsulphoxide (DMSO), and methane (CH4), as well as various phytoplankton marker pigments in the surface ocean were measured along a north-south transit from Japan to Australia in October 2009. DMS (0.9 nmol l-1), dissolved DMSP (DMSPd, 1.6 nmol l-1) and particulate DMSP (DMSPp, 2 nmol l-1) concentrations were generally low, while dissolved DMSO (DMSOd, 4.4 nmol l-1) and particulate DMSO (DMSOp, 11.5 nmol l-1) concentrations were comparably enhanced. Positive correlations were found between DMSO and DMSP as well as DMSP and DMSO with chlorophyll a, which suggests a similar source for both compounds. Similar phytoplankton groups were identified as being important for the DMSO and DMSP pool, thus, the same algae taxa might produce both DMSP and DMSO. In contrast, phytoplankton seemed to play only a minor role for the DMS distribution in the western Pacific Ocean. The observed DMSPp : DMSOp ratios were very low and seem to be characteristic of oligotrophic tropical waters representing the extreme endpoint of the global DMSPp : DMSOp ratio vs. SST relationship. It is most likely that nutrient limitation and oxidative stress in the tropical West Pacific Ocean triggered enhanced DMSO production leading to an accumulation of DMSO in the sea surface. Positive correlations between DMSPd and CH4, as well as between DMSO (particulate and total) and CH4, were found along the transit. We conclude that both DMSP and DMSO serve as substrates for methanogenic bacteria in the western Pacific Ocean.

  19. The diverse crustal structure and magmatic evolution of the Manihiki Plateau, central Pacific

    Directory of Open Access Journals (Sweden)

    K. Hochmuth

    2014-07-01

    Full Text Available The Manihiki Plateau is a Large Igneous Province (LIP in the central Pacific. It was emplaced as part of the "Super-LIP" Ontong Java Nui and experienced fragmentation into three sub-plateaus, possibly during the break-up of Ontong Java Nui. The Manihiki Plateau is presumably the centerpiece of this "Super-LIP" and its investigation can therefore decipher the break-up mechanisms as well as the evolution of the plateau after its initial emplacement. By analyzing two seismic refraction/wide-angle reflection profiles crossing the two largest sub-plateaus of the Manihiki Plateau, the High Plateau and the Western Plateaus, we give new insights into their crustal structure and magmatic evolution. The High Plateau shows a crustal structure of 20 km thickness and a seismic P wave velocity distribution, which is comparable to other LIPs. The High Plateau experienced a strong secondary volcanism, which can be seen in relicts of seamount chain volcanism. The Western Plateaus on the other hand show no extensive secondary volcanism and are mainly structured by fault systems and sedimentary basins. A constant decrease in Moho depth (9–17 km is a further indicator of crustal stretching on the Western Plateaus. Those findings lead to the conclusion, that the two sub-plateaus of the Manihiki Plateau experienced a different magmatic and tectonic history. Whereas the High Plateau experienced a secondary volcanism, the Western Plateaus underwent crustal stretching during and after the break-up of Ontong Java Nui. This indicates, that the sub-plateaus of the Manihiki Plateau play an individual part in the break-up history of Ontong Java Nui.

  20. Classification of seamount morphology and its evaluating significance of ferromanganese crust in the central Pacific Ocean

    Institute of Scientific and Technical Information of China (English)

    CHU Fengyou; SUN Guosheng; MA Weilin; LI Shoujun; QIAN Xinyan; ZHAO Hongqiao

    2006-01-01

    Using the SeaBeam technology, the morphology of seamount and its relation to the formation of cobalt-rich crust in the central Pacific Ocean were surveyed during the cruise in 2003 for marine mineral resources. The result shows that seamounts can be divided morphologically into the spire seamount and the flat topped seamount. These two types of seamount bear great differences in their landform, lithology and cobalt-rich crust. On the upper portion of the flat topped seamount, the flat top and the sharp escarpments are unfavorable to the growth of crust, and, consequently, the crusts here are mostly laminar or gravelly, their thicknesses generally show great variations, and the consecutive ore body often develops in its deep water region. On the spire topped seamount, however, the flat area is small, and its gradient is constant without large variation from the top to the bottom. This favors the growth of cobalt-rich crust and often leads to consecutive tabular ore body of medium thickness, occurring on the spire topped seamount from the shallow water region to the deep water region. The cobalt-rich crust on the spire topped seamount is much better than that on the flat topped seamount for the crust abundance, crust coverage and number of ore-occurrences within unit area. Furthermore, the crust on the spire topped seamount is rich in cobalt, nickel, manganese elements of high economic value. Because the crust with high quality ore often occurs in the shallow water region on the spire topped seamount, it can be mined and use more easily in the future.

  1. The diverse crustal structure and magmatic evolution of the Manihiki Plateau, central Pacific

    Science.gov (United States)

    Hochmuth, K.; Gohl, K.; Uenzelmann-Neben, G.; Werner, R.

    2014-07-01

    The Manihiki Plateau is a Large Igneous Province (LIP) in the central Pacific. It was emplaced as part of the "Super-LIP" Ontong Java Nui and experienced fragmentation into three sub-plateaus, possibly during the break-up of Ontong Java Nui. The Manihiki Plateau is presumably the centerpiece of this "Super-LIP" and its investigation can therefore decipher the break-up mechanisms as well as the evolution of the plateau after its initial emplacement. By analyzing two seismic refraction/wide-angle reflection profiles crossing the two largest sub-plateaus of the Manihiki Plateau, the High Plateau and the Western Plateaus, we give new insights into their crustal structure and magmatic evolution. The High Plateau shows a crustal structure of 20 km thickness and a seismic P wave velocity distribution, which is comparable to other LIPs. The High Plateau experienced a strong secondary volcanism, which can be seen in relicts of seamount chain volcanism. The Western Plateaus on the other hand show no extensive secondary volcanism and are mainly structured by fault systems and sedimentary basins. A constant decrease in Moho depth (9-17 km) is a further indicator of crustal stretching on the Western Plateaus. Those findings lead to the conclusion, that the two sub-plateaus of the Manihiki Plateau experienced a different magmatic and tectonic history. Whereas the High Plateau experienced a secondary volcanism, the Western Plateaus underwent crustal stretching during and after the break-up of Ontong Java Nui. This indicates, that the sub-plateaus of the Manihiki Plateau play an individual part in the break-up history of Ontong Java Nui.

  2. 234Th, 210Pb, 210Po and stable Pb in the central equatorial Pacific: Tracers for particle cycling

    Science.gov (United States)

    Murray, J.W.; Paul, B.; Dunne, J.P.; Chapin, T.

    2005-01-01

    Samples were collected during the 1992 US JGOFS EqPac Survey I and II cruises from 12??N to 12??S at 140??W in the central equatorial Pacific for water column profiles of dissolved, particulate and total 234Th, 210Pb and 210Po and total acid soluble stable Pb and sediment trap fluxes of 234Th, 210Pb and 210Po. Survey I occurred in February/March with moderate El Nino conditions while Survey II was conducted in September/October when there was a well developed cold-tongue. 234Th, 210Pb and 210Po are all particle reactive yet they partition differently between dissolved and particulate phases. Fractionation factors (the ratios of the distribution coefficients) show that the selectivity for suspended and sediment trap particles follows Th>Po>Pb. Scavenging residence times (??) for 234Th, 210Pb and 210Po ranged from 25 to 100 d, 3 to 8 years and 100 to 500 d, respectively. These particle reactive tracers have very different distributions in the water column, which reflect differences in their sources and sinks. The deficiency of 234Th relative to 238U was fairly uniformly distributed meridionally, though deficiencies were higher during Survey II when there was higher new production. Excess 210Pb relative to 226Ra was very asymmetrical with much higher excess values north of the equator. The distributions were similar for Surveys I and II. The deficiency of 210Po relative to 210Pb had a symmetrical distribution about the equator for both Survey I and II but the deficiencies were larger during Survey I when upwelling was smaller. Stable Pb was generally higher at the surface than at 250 m and there was no meridional trend from 12??N to 12??S. A mass balance for 210Pb was used to determine the atmospheric input of 210Pb. The average values for Surveys I and II were 0.12 and 0.32 dpm cm-2 year-1, respectively. There was no general increase in atmospheric input of 210Pb north of the equator but there was a strong maximum at 2-3??N during Survey I coincident with the

  3. Status Assessment of Laysan and Black-Footed Albatrosses, North Pacific Ocean, 1923-2005

    Science.gov (United States)

    Arata, Javier A.; Sievert, Paul R.; Naughton, Maura B.

    2009-01-01

    Over the past century, Laysan (Phoebastria immutabilis) and black-footed (Phoebastria nigripes) albatrosses have been subjected to high rates of mortality and disturbance at the breeding colonies and at sea. Populations were greatly reduced and many colonies were extirpated around the turn of the 20th century as a result of feather hunting. Populations were recovering when military occupation of several breeding islands during World War II led to new population declines at these islands and additional colony extirpations. At sea, thousands of Laysan and black-footed albatrosses were killed each year in high-seas driftnet fisheries, especially from 1978 until the fisheries were banned in 1992. Through the 1990s, there was a growing awareness of the large numbers of albatrosses that were being killed in longline fisheries. During the 1990s, other anthropogenic factors, such as predation by non-native mammals and exposure to contaminants, also were documented to reduce productivity or increase mortality. In response to the growing concerns over the impacts of these threats on albatross populations, the U.S. Fish and Wildlife Service contracted with the U.S. Geological Survey to conduct an assessment of Laysan and black-footed albatross populations. This assessment includes a review of the taxonomy, legal status, geographic distribution, natural history, habitat requirements, threats, and monitoring and management activities for these two species. The second part of the assessment is an analysis of population status and trends from 1923 to 2005. Laysan and black-footed albatrosses forage throughout the North Pacific Ocean and nest on tropical and sub-tropical oceanic islands from Mexico to Japan. As of 2005, 21 islands support breeding colonies of one or both species. The core breeding range is the Hawaiian Islands, where greater than 99 percent of the World's Laysan albatrosses and greater than 95 percent of the black-footed albatrosses nest on the small islands and

  4. Palaeoceanographic conditions during the formation of ferromanganese crust from the Afanasiy Nikitin seamount, north central Indian Ocean: geochemical evidence

    Digital Repository Service at National Institute of Oceanography (India)

    Banakar, V.K.; Pattan, J.N.; Mudholkar, A.V.

    of the Central Pacific Basin, Circum-Pac. Comic. Energy Miner. Resour. (Earth. Sci. Ser., 15). Springer, New York, pp. 261-283. Hein. J.R., Bohrson, W.A., Schulz, M.S., Noble, M. and Clague, D.A., 1992b. Variation in the fine scale composition of a central...

  5. Cross-spectral study of the spatial relationships in the North Pacific sea-surface temperature anomaly field. Report No. 23

    Energy Technology Data Exchange (ETDEWEB)

    Middleton, J.W.

    1980-03-01

    Cross-spectral analysis is used to examine the dependence of the temporal covariation of sea-surface temperature (SST) anomalies at pairs of spatially separated points in the North Pacific on (1) the time scale of the variations, (2) the relative displacement of the points and (3) their location within the North Pacific basin. Spatial scales considered here range from 1000 kilometers up to the width of the basin. The study focuses on cross-spectral estimates for the interannual frequency band, 0.125-0.75 yr/sup -1/ although estimates for three other bands spanning higher frequencies are also examined.

  6. Techno-Arrogance and Halfway Technologies: Salmon Hatcheries on the Pacific Coast of North America.

    Science.gov (United States)

    Meffe, Gary K.

    1993-01-01

    Discusses an attempt to recover Pacific salmonid fisheries with hatcheries as an example of a human attitude toward nature that places technological mastery over nature at the forefront of our approach to many environmental problems. Points out how this approach addresses the symptoms but not the causes of the salmon population decline. Suggests…

  7. A seamless, high-resolution digital elevation model (DEM) of the north-central California coast

    Science.gov (United States)

    Foxgrover, Amy C.; Barnard, Patrick L.

    2012-01-01

    A seamless, 2-meter resolution digital elevation model (DEM) of the north-central California coast has been created from the most recent high-resolution bathymetric and topographic datasets available. The DEM extends approximately 150 kilometers along the California coastline, from Half Moon Bay north to Bodega Head. Coverage extends inland to an elevation of +20 meters and offshore to at least the 3 nautical mile limit of state waters. This report describes the procedures of DEM construction, details the input data sources, and provides the DEM for download in both ESRI Arc ASCII and GeoTIFF file formats with accompanying metadata.

  8. Investigations of the preferred modes of north Pacific jet variability, their downstream impacts, and tropical and extratropical precursors

    Science.gov (United States)

    Griffin, Kyle S.

    Time extended EOF (TE-EOF) analysis is employed to examine the synoptic-scale evolution of the two leading modes of north Pacific jet stream variability, namely its zonal extension/retraction (TE-EOF 1) and the north/south shift of its exit region (TE-EOF 2). Composite analyses are constructed preceding and following peaks in the principal component associated with each of the two TE-EOFs, providing insight into the preferred evolutions of the north Pacific jet. Jet extension events are associated with an anomalous Gulf of Alaska cyclone, while jet retractions are associated with an anomalous ridge over the Aleutians. Similar but shifted upper level patterns are noted with the corresponding poleward/equatorward shifted jet phases, with the poleward (equatorward) shift of the jet exit region associated with anomalous low-level warmth (cold) over western North America. Such composites also suggest connections between certain phases of these leading modes of jet variability and deep convection in the tropics, a connection that has been challenging to physically diagnose in previous studies. The isentropic pressure depth measures the mass contained within an isentropic layer in a given grid column, enabling the tracking of mass exhausted by deep convection. The gradient of isentropic pressure depth is directly associated with the vertical geostrophic wind shear in that layer and thus provides a means to track the influence of convective mass flux on the evolution of the jet stream. A case study focused on the extreme North American warm episode of March 2012 demonstrates how positive pressure depth anomalies from a strong MJO event impact the jet stream over eastern Asia and drive a portion of the mid-latitude response that leads to the flow amplification and subsequent downstream warmth. This study demonstrates one way by which isentropic pressure depth can diagnose the impacts of tropical deep convection on the mid-latitude circulation. Using TE-EOFs, composites of

  9. Zooplankton abundance, biovolume and size spectra at western boundary currents in the subtropical North Pacific during winter 2012

    Science.gov (United States)

    Dai, Luping; Li, Chaolun; Yang, Guang; Sun, Xiaoxia

    2016-03-01

    Horizontal changes in mesozooplankton abundance, biovolume and size spectra at western boundary currents in the subtropical North Pacific during winter 2012 were evaluated by ZooScan measurement on samples collected by net towing from 23 stations. Zooplankton abundance and biovolume ranged from 35.1 to 456.8 ind. m- 3 and 4.3 to 231.7 mm3 m- 3, respectively. Copepoda were the most dominant species, followed by Chaetognatha and Tunicata. According to the Bray-Curtis cluster analysis based on biovolume of zooplankton size classes of each taxonomic group at intervals of 1 (log2 mm3 ind.- 1) between - 6 and 12 and considering the effect of regional factors, zooplankton communities were classified into four groups, which basically coincided with the geographical patterns of different currents: the North Equatorial Current (NEC), the North Equatorial Counter Current (NECC), the Kuroshio Current (KC), and the Mindanao Eddy (ME), respectively. The largest and lowest biovolumes were observed in the NECC region and the NEC region, respectively, and both were dominated by the 0.3 to 1 mm equivalent spherical diameter (ESD) size class, while the ME region was dominant by the 1 to 2 mm ESD size class. The slopes of the normalized biovolume size spectra for each group were slightly lower than - 1 (range from - 0.85 to - 0.92), which indicates that zooplankton communities in the study area were characterized by low productivity and high energy transfer efficiency.

  10. U/Th-dating living and young fossil corals from the central tropical Pacific

    Science.gov (United States)

    Cobb, Kim M.; Charles, Christopher D.; Cheng, Hai; Kastner, Miriam; Edwards, R. Lawrence

    2003-05-01

    This study evaluates the accuracy of U/Th dates for young (reef corals, both living and fossil, and explores strategies for refining those dates. The high precision of the U/Th method (±1-2%) for dating young corals is well-established. Earlier studies have demonstrated the method's accuracy for select samples of known age. However, these studies have focused on typical samples that have extremely low 232Th concentrations (tens of pg/g). Here we study the dating systematics of young corals that have low but significant amounts of 232Th (up to 1000 pg/g), indicating the presence of small fractions of non-radiogenic 230Th (i.e. 230Th not generated by in situ U decay). We report U/Th ages for living and subaerially exposed fossil corals from Palmyra Island, located in the central tropical Pacific, that range from 50 to 700 yr old. The Palmyra corals contain varying amounts of 232Th and small fractions of associated non-radiogenic 230Th. Uncertainty associated with the correction for non-radiogenic 230Th can lead to significant errors in U/Th dates. We have characterized non-radiogenic 230Th/ 232Th values, ( 230Th/ 232Th) nr, as a means of minimizing this source of error. We calculate ( 230Th/ 232Th) nr values ranging from 0 to 2×10 -5 for the Palmyra living corals by comparing measured U/Th dates to absolute dates for the living coral, whose chronology is well-established. For the fossil corals, we employ three different approaches to arrive at ( 230Th/ 232Th) nr estimates. First, we compare measured U/Th dates to absolute dates in samples from a young fossil coral that overlaps the living coral. Next, we use the firm relative dating constraints imposed by five overlapping fossil corals from the 14th-15th centuries to calculate ( 230Th/ 232Th) nr values. Finally, we attempt to anchor the 14th-15th century floating coral chronology to an absolute chronology by correlating the climate signals in the coral records to those in absolutely dated climate proxy records. All

  11. [Species and size composition of fishes in Barra de Navidad lagoon, Mexican central Pacific].

    Science.gov (United States)

    González-Sansón, Gaspar; Aguilar-Betancourt, Consuelo; Kosonoy-Aceves, Daniel; Lucano-Ramírez, Gabriela; Ruiz-Ramírez, Salvador; Flores-Ortega, Juan Ramón; Hinojosa-Larios, Angel; de Asís Silva-Bátiz, Francisco

    2014-03-01

    State, and it also constitutes the more complete reference on the detailed size composition of a set of dominant species in a coastal lagoon in the central Mexican Pacific.

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

    Directory of Open Access Journals (Sweden)

    J. Charpentier

    2007-05-01

    Full Text Available The biogeochemical mechanism of bacterial N2O production in the ocean has been the subject of many discussions in recent years. New isotopomeric tools can help further knowledge on N2O sources in natural environments. This research shows and compares hydrographic, nitrous oxide concentration, and N2O isotopic and isotopomeric data from three stations across the South Pacific Ocean, from the center of the subtropical oligotrophic gyre (~26° S; 114° W to the upwelling zone along the central Chilean coast (~34° S. Althought AOU/N2O and NO3 trends support the idea that most of N2O source (mainly from intermediate water (200–1000 m come from nitrification, N2O isotopomeric composition (intramolecular distribution of 15N isotopes in N2O reveals an abrupt change in the mechanism of nitrous oxide production, always observed through lower SP (site preference of 15N, at a high – stability layer, where particles could act as microsites and N2O would be produced by nitrifier denitrification (reduction of nitrite to nitrous oxide mediated by primary nitrifiers. There, nitrifier denitrification can account for 40% and 50% (center and east border of the gyre, respectively of the nitrous oxide produced in this specific layer. This process could be associated with the deceleration of sinking organic particles in highly stable layers of the water column. In constrast, coastal upwelling system is characterized by oxygen deficient condition and some N deficit in a eutrophic system. Here, nitrous oxide accumulates up to 480% saturation, and isotopic and isotopomer signal show highly complex nitrous oxide production processes, which presumably reflect both the effect of nitrification and denitrification at low oxygen levels on N2O production, but non N2O consumption by denitrification was observed.

  13. 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

  14. Environmental history of mangrove vegetation in Pacific west-central Mexico during the last 1300 years

    Directory of Open Access Journals (Sweden)

    Blanca Lorena Figueroa-Rangel

    2016-08-01

    Full Text Available AbstractMangroves are a highly threatened ecosystem due to climate change and human activity, which increases coastal vulnerability. Knowledge about the ecological dynamics of mangroves on a centennial timescale can reveal the different responses in vegetation, which is useful for implementing basic actions for mangrove restoration, conservation and management. A mangrove ecosystem in the Cuyutlán Lagoon area along the Pacific coast of west-central Mexico is significantly altered as a result of industrialization, salt extraction, and road construction. The long-term dynamics of the mangrove ecosystem has also been controlled by Holocene climatic variability. This study reconstructs the environmental history of mangrove vegetation around the Cuyutlán Lagoon during the last ~1300 years in response to periods of human activity and climate change. The reconstruction was performed using paleoecological techniques in sediment cores that include the use of fossil pollen as a proxy for vegetation and magnetic susceptibility and geochemical data (determined by loss-on-ignition and X-ray fluorescence as a proxy for past environmental changes. The chronology was determined using 14C dating and the age-depth model was constructed by linear interpolation. Redundancy analysis and non-metric multidimensional scaling (NMDS were used to discern patterns of distribution of the different proxies. Results revealed that the mangrove pollen assemblage of the Cuyutlán Lagoon was dominated by the arboreal taxa Rhizophora mangle, Euphorbiaceae, Moraceae and Pinaceae, herbaceous taxa like Poaceae, Chenopodiaceae/Amaranthaceae, and aquatics such as Typhaceae and Cyperaceae. NMDS showed a clear separation between two events of human activity—the Spanish Occupation of Colima (~AD 1523-1524 and the opening of the Manzanillo port (~AD 1824-1825. Climate change events such as the Medieval Climate Anomaly (MCA (~AD 800-1200 and the Little Ice Age (LIA (~AD 1350-1850 were

  15. Anthropogenic processing of dust affects the oxygen content of the North Pacific Ocean

    Science.gov (United States)

    Nenes, Athanasios; Ito, Taka; Johnson, Matthew; Meskhidze, Nicholas; Valett, Jackie; Deutsch, Curtis

    2015-04-01

    Observations from the last several decades show a significant expansion of the tropical Pacific oxygen minimum zone (OMZ). However, the underlying causes remain elusive, as the currently accepted effects of ocean warming and associated solubility decease cannot fully explain the observed oxygen trend. Here we show that anthropogenic pollution can change the pattern of biological productivity and oxygen trends consistent with observations in the tropics and extratropics. These effects are caused by the mobilization of iron in mineral dust by pollutants, where it is transported and deposited to the HNLC regions of the tropical pacific affecting primary productivity and oxygen consumption by bacterial respiration. In this study, it is shown that pollution-mobilized iron deposited to high latitude oceanic environments can profoundly impact subsurface oxygen and the extent of the OMZ through long-range oceanic transport. Together with the intensification of tropical upwelling since the 1990s associated with natural climate variability, our results can explain the expansion of the OMZ in the tropical Pacific in the late twentieth century. Unlike climate variability, however, anthropogenic pollution likely influences the long-term trends in marine biogeochemistry and further alters regional productivity and subsurface oxygen distributions with profound implications for marine habitats and nitrate inventory of the oceans.

  16. Contrasting distributions of dissolved gaseous mercury concentration and evasion in the North Pacific Subarctic Gyre and the Subarctic Front

    Science.gov (United States)

    Kim, Hyunji; Rhee, Tae Siek; Hahm, Doshik; Hwang, Chung Yeon; Yang, Jisook; Han, Seunghee

    2016-04-01

    The distribution of dissolved gaseous mercury (DGM) and the oxidation-reduction processes of mercury (Hg) in the surface and subsurface ocean are currently understudied despite their importance in ocean-atmosphere interactions. We investigated the Hg(0) evasion and the DGM distribution at water depths of 2-500 m in the Subarctic Front, Western Subarctic Gyre, and Bering Sea of the Northwestern Pacific. The mean DGM concentration in the surface mixed water (chlorophyll-a concentration and extracellular protease activity predicted 54% and 48% of the DGM variation, respectively, in the euphotic zone (2-50 m). The DGM concentration in aphotic intermediate water (415±286 fM) was positively correlated to the apparent oxygen utilization (AOU; r2=0.94 and p<0.001 for the Western Subarctic Gyre and the Bering Sea; r2=0.61 and p=0.01 for the Subarctic Front), emphasizing the importance of microbial oxidation of organic matter. The DGM-to-AOU ratio in aphotic water was significantly (p<0.05, ANCOVA) higher at the Western Subarctic Gyre and Bering Sea sites (2.5±0.14) than the ratio at the Subarctic Front sites (0.89±0.27) that mainly consisted of newly formed North Pacific Intermediate Water. The overall results imply that variation of DGM and Hg(0) evasion is closely linked to primary production in euphotic water and organic remineralization in aphotic intermediate water. The oceanic alterations in these factors may induce significant modification in Hg redox speciation in the Northwestern Pacific.

  17. Distribution of {delta}{sup 14}C in western North Pacific and tracing carbons of human origin

    Energy Technology Data Exchange (ETDEWEB)

    Aramaki, Takafumi; Mizushima, Toshihiko; Togawa, Orihiko [Japan Atomic Energy Research Inst., Mutsu, Aomori (Japan). Mutsu Establishment; Watanabe, Shuichi; Tsunogai, Shizuo [Hokkaido Univ., Sapporo (Japan); Kuji, Tomoyuki [Japan marine Sience Fundation, Mutsu, Aomori (Japan)

    2001-02-01

    Seawater were collected at six points, 0deg to 48degN around 165degE. Dissolved inorganic carbonates was reduced into graphite. The ratio C-11/C-12 was measured by the accelerator mass analyzer. {sup 14}C concentration was calculated from {delta}{sup 13}C value calculated from the {sup 13}C/{sup 12}C ratio. {sup 14}C resulting from the nuclear weapon test was calculated by comparing estimated {sup 14}C and real {sup 14}C concentration. It was compared with that in 1970s. {sup 14}Cbomb has dissolved into North Pacific Intermediate Water in Arctic latitude, which has moved to Mid-latitude. (A. Yamamoto)

  18. Intraseasonal variability and tropical cyclogenesis in the western North Pacific simulated by a global nonhydrostatic atmospheric model

    Science.gov (United States)

    Nakano, Masuo; Sawada, Masahiro; Nasuno, Tomoe; Satoh, Masaki

    2015-01-01

    successive daily experiments for extended-range (30 day) forecasts are conducted using a global nonhydrostatic atmospheric model without convective parameterization. The model successfully reproduces tropical cyclogenesis (TCG) in six out of eight cases in the western North Pacific in August 2004, up to 2 weeks prior to cyclone formation. Detailed analyses reveal that Typhoon Songda's genesis is related to the eastward extension of the monsoon trough associated with the intraseasonal variability (ISV). The successful simulation of the migration and extension of the monsoon trough leads to a 2 week forecast for Songda's genesis. These findings highlight the need for a model capable of predicting the modulation of large-scale fields by ISV for TCG forecasts and that a global nonhydrostatic cloud-system-resolving model is a promising tool for TCG forecasts.

  19. Introduction to the North Pacific Research Board Gulf of Alaska Integrated Ecosystem Research Program (GOAIERP): Volume I

    Science.gov (United States)

    Dickson, Danielle M. S.; Baker, Matthew R.

    2016-10-01

    The North Pacific Research Board (NPRB) supports research to address pressing fishery management and ecosystem information needs in the marine waters of Alaska. Understanding dynamics at the scale of ecosystems requires integrated approaches that explore underlying mechanistic processes and interactions. It also requires analytic approaches that investigate the influence, cause, effect, and relative importance of various phenomena and drivers in determining ecosystem structure, processes and biophysical interactions. To address ecosystem-level hypotheses and questions at this scale, NPRB developed the Integrated Ecosystem Research Program (IERP). These programs employ multi-disciplinary and multi-institutional approaches to investigating ecosystem processes. The aim is to provide a basis for understanding core processes and to provide information and products that have targeted application to management priorities.

  20. Population differentiation and hybridisation of Australian snubfin (Orcaella heinsohni) and Indo-Pacific humpback (Sousa chinensis) dolphins in North-Western Australia

    NARCIS (Netherlands)

    Brown, Alexander M.; Kopps, Anna M.; Allen, Simon J.; Bejder, Lars; Littleford-Colquhoun, Bethan; Parra, Guido J.; Cagnazzi, Daniele; Thiele, Deborah; Palmer, Carol; Frere, Celine H.

    2014-01-01

    Little is known about the Australian snubfin (Orcaella heinsohni) and Indo-Pacific humpback (Sousa chinensis) dolphins (‘snubfin’ and ‘humpback dolphins’, hereafter) of north-western Australia. While both species are listed as ‘near threatened’ by the IUCN, data deficiencies are impeding rigorous as

  1. The Role of the Kuroshio in the Winter North Pacific Ocean-Atmosphere Interaction: Comparison of a Coupled Model and Observations

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A comparative study between the output of the Flexible Global Climate Model Version 1.0 (FGCM-1.0) and the observations is performed. At 500 hPa, the geopotential height of FGCM is similar to the observations, but in the North Pacific the model gives lower values, and the differences are most significant over the northern boundary of the Pacific. In a net heat flux comparison, the spatial patterns of the two are similar in winter, but more heat loss appears to the east of Japan in FGCM than in COADS. On the interannual timescale, strong (weak) Kuroshio transports to the east of Taiwan lead the increasing (decreasing) net heat flux, which is centered over the Kuroshio Extension region, by 1-2 months, with low (high) pressure anomaly responses appearing at 500 hPa over the North Pacific (north of 25°N) in winter.The northward heat transport of the Kuroshio is one of the important heat sources to support the warming of the atmosphere by the ocean and the formation of the low pressure anomaly at 500 hPa over the North Pacific in winter.

  2. Wildlife use of existing culverts and bridges in North Central Pennsylvania

    OpenAIRE

    Brudin, Carl O. III

    2003-01-01

    The Pennsylvania Department of Transportation (PENNDOT) District 3-0 initiated a study in North Central Pennsylvania evaluating existing bridges and culverts for use as underpasses by wildlife. This project was a two-phase study to investigate animal passage through existing drainage box culverts, arch culverts and bridges on existing highway systems. The objective of this study was to (1) determine whether wildlife are using existing structures as passageways based on wildlife sign and remot...

  3. Radiological health assessment of natural radioactivity in the vicinity of Obajana cement factory, North Central Nigeria

    OpenAIRE

    Omoniyi Matthew Isinkaye; Jibiri, Nnamdi N.; Adebowale A Olomide

    2015-01-01

    Measurements of activity concentrations of natural radionuclides in and around Obajana cement factory, North Central Nigeria have been carried out in this study to determine the activity levels of natural radionuclides in different environmental matrices in order to assess the radiological health hazards associated with the use of these matrices by the local population. A low-background Pb-shielded gamma spectroscopic counting assembly utilizing NaI (Tl) detector was employed for the measurem...

  4. Drinking water and pregnancy outcome in central North Carolina: source, amount, and trihalomethane levels.

    OpenAIRE

    Savitz, D A; Andrews, K W; Pastore, L M

    1995-01-01

    In spite of the recognition of potentially toxic chemicals in chlorinated drinking water, few studies have evaluated reproductive health consequences of such exposure. Using data from a case-control study of miscarriage, preterm delivery, and low birth weight in central North Carolina, we evaluated risk associated with water source, amount, and trihalomethane (THM) concentration. Water source was not related to any of those pregnancy outcomes, but an increasing amount of ingested water was as...

  5. Strategic Planning for Activation and Operation of the North Central Superpave Center (NCSC): Interim Report

    OpenAIRE

    Olek, J.; McDaniel, Rebecca

    1997-01-01

    The North Central Superpave Center (NCSC) was established to serve the needs of the states and industry in ten states and two Canadian provinces as they implement the Superpave system. Accomplishing this goal requires the cooperation and active support of a number of people and organizations. Organizational and operational issues related to infrastructure, personnel, equipment and finances also needed to be resolved. This project was designed to address those issues, develop a comprehensive s...

  6. Semi-automated characterisation of seabed pockmarks in the central North Sea

    OpenAIRE

    Gafeira, J.; Long, D; Diaz-Doce, D.

    2012-01-01

    Pockmarks are indicators of focused fluid seepage, most notably gas such as methane, and can occur in vast numbers in many marine and even in lacustrine environments. The presence and distribution of pockmarks need to be considered in the development of any infrastructure at the seabed. However, manual mapping of these features can be extremely time-consuming and it is implicitly subjective. An extensive area in the central North Sea, where the seabed comprises a thick sequence of muds and sa...

  7. Appraisal of Rural Water Supply: Case Study of Kwara State, North Central Nigeria

    OpenAIRE

    Peter Aderemi Adeoye; Adesiji Richard Adeolu; Hassana Mustapha Ibrahim

    2013-01-01

    Provision of clean domestic water for both rural and urban dwellers should be seen as a necessity by policy makers. However, this is not so for developing nations where rural dwellers are neglected whenever water supply schemes are been contemplated. This paper assessed rural water supply system in Kwara State, North Central Nigeria. Questionnaires were administered to respondents in the area under investigation for quantitative evaluation while samples were taken from their prevailing water...

  8. Influences of the El Nino Southern Oscillation and the Pacific Decadal Oscillation on the Timing of the North American Spring

    Science.gov (United States)

    McCabe, Gregory J.; Ault, Toby R.; Cook, Benjamin I.; Betancourt, Julio L.; Schwartz, Mark D.

    2012-01-01

    Detrended, modelled first leaf dates for 856 sites across North America for the period 1900-2008 are used to examine how the El Nino Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO) separately and together might influence the timing of spring. Although spring (mean March through April) ENSO and PDO signals are apparent in first leaf dates, the signals are not statistically significant (at a 95% confidence level (p Nino and positive PDO conditions. An analysis of the spatial distributions of first leaf dates for separate and combined ENSO/PDO conditions features a northwest-southeast dipole that is significantly (at p <0.05) different than the distributions for neutral conditions. The nature of the teleconnection between Pacific SST's and first leaf dates is evident in comparable composites for detrended sea level pressure (SLP) in the spring months. During positive ENSO/PDO, there is an anomalous flow of warm air from the southwestern US into the northwestern US and an anomalous northeasterly flow of cold air from polar regions into the eastern and southeastern US. These flow patterns are reversed during negative ENSO/PDO. Although the magnitudes of first leaf date departures are not necessarily significantly related to ENSO and PDO, the spatial patterns of departures are significantly related to ENSO and PDO. These significant relations and the long-lived persistence of SSTs provide a potential tool for forecasting the tendencies for first leaf dates to be early or late.

  9. The Structure of Genetic Diversity in Eelgrass (Zostera marina L.) along the North Pacific and Bering Sea Coasts of Alaska

    Science.gov (United States)

    Talbot, Sandra L.; Sage, George K; Rearick, Jolene R.; Fowler, Meg C.; Muñiz-Salazar, Raquel; Baibak, Bethany; Wyllie-Echeverria, Sandy; Cabello-Pasini, Alejandro; Ward, David H.

    2016-01-01

    Eelgrass (Zostera marina) populations occupying coastal waters of Alaska are separated by a peninsula and island archipelago into two Large Marine Ecosystems (LMEs). From populations in both LMEs, we characterize genetic diversity, population structure, and polarity in gene flow using nuclear microsatellite fragment and chloroplast and nuclear sequence data. An inverse relationship between genetic diversity and latitude was observed (heterozygosity: R2 = 0.738, P < 0.001; allelic richness: R2 = 0.327, P = 0.047), as was significant genetic partitioning across most sampling sites (θ = 0.302, P < 0.0001). Variance in allele frequency was significantly partitioned by region only in cases when a population geographically in the Gulf of Alaska LME (Kinzarof Lagoon) was instead included with populations in the Eastern Bering Sea LME (θp = 0.128–0.172; P < 0.003), suggesting gene flow between the two LMEs in this region. Gene flow among locales was rarely symmetrical, with notable exceptions generally following net coastal ocean current direction. Genetic data failed to support recent proposals that multiple Zostera species (i.e. Z. japonica and Z. angustifolia) are codistributed with Z. marina in Alaska. Comparative analyses also failed to support the hypothesis that eelgrass populations in the North Atlantic derived from eelgrass retained in northeastern Pacific Last Glacial Maximum refugia. These data suggest northeastern Pacific populations are derived from populations expanding northward from temperate populations following climate amelioration at the terminus of the last Pleistocene glaciation. PMID:27104836

  10. Surface constraints on the temporal and spatial evolution of the Farallon-Pacific-North America plate boundary

    Science.gov (United States)

    McQuarrie, N.; Oskin, M.

    2009-05-01

    Extension and volcanism are two surface derived data sets used to infer mantle processes back in time. We integrate two new large GIS-based datasets to create palinspastic restorations of extension and volcanism allowing us to readdress the relationship between plate-boundary deformation, intra-plate extension and magmatism in western North America. Using ArcGIS and custom software, we retrodeformed the NAVDat (North American Volcanic Database, navdat.geongrid.org) using the western North America reconstruction of McQuarrie and Wernicke (2005). We compare this data to strain rates calculated over a 50 km-grid forward- deformed from 36 Ma to present. With the deformed grid and palinspastically restored volcanic dataset we quantitatively compare rates of magmatism and deformation and evaluate the age, location, and migration of Cenozoic volcanic arcs. A first order conclusion from this study is that magmatism, throughout the Basin and Range, is primarily driven by plate boundary effects. The plate boundary effects include subduction and rollback of the Farallon plate, creation and expansion of slab windows as the Pacific plate intercepts the North American plate and re-establishment of the ancestral Cascade arc along the eastern margin of the Sierra Nevada at ˜ 15 Ma. Notable exceptions include the Yellowstone hotspot system along the northern boarder of our study area and late-stage (<8 Ma) passive, extension related asthenospheric upwelling that accompanied a thinning lithosphere along the eastern and western margins of the Basin and Range. The palinspastic reconstructions presented here highlight that the classic, high-angle, Basin and Range faulting that comprises most of the physiographic Basin and Range province commenced during a remarkably amagmatic period. These observations largely contradicts the active rifting model where magmatism triggers Basin and Range extension

  11. Spatiotemporal distribution of seawater pH in the North Pacific subpolar region by using the parameterization technique

    Science.gov (United States)

    Li, Bofeng; Watanabe, Yutaka W.; Yamaguchi, Azusa

    2016-05-01

    We provided parameterizations to speculate changes in the vertical distributions of the seawater total alkalinity (TA), dissolved inorganic carbon (DIC), and pH by using all available observations of dissolved oxygen (DO, µmol kg-1), water temperature (T, ºC), and salinity (S) data from previous high quality data sets of ocean hydrographic properties. All data sets were collected in the North Pacific subpolar region during the period of 2000-2010, for 40-400 m depth, and between 40°N and 56°N, 145°E and 130°W). Root mean square errors for the parameterizations with 7.4 µmol kg-1 for TA, 7.1 µmol kg-1 for DIC, and 0.02 for pH were obtained with R2 of more than 0.95. To evaluate the validity of these parameterizations, we compared measured TA, DIC, and pH with predicted values. The differences were almost within 10 µmol kg-1 for TA and DIC, and 0.05 for pH. Applying our parameterizations to the climatological data sets of DO, T, and S data from World Ocean Atlas 2009, we reconstructed seasonal and monthly vertical distributions of seawater TA, DIC, and pH. Furthermore, by substituting our parameterizations into detailed vertical distributions of DO, T, and S data measured bi-weekly by automatic ocean hydrographic sensors from Argo profiling floats, we described the detailed vertical spatiotemporal distributions of seawater TA, DIC, and pH. In the North Pacific subpolar region, in the case that there is no time-series of ocean carbon species, our parameterizations allowed us to elucidate the dynamics of ocean carbon chemistry from two-week scale to decadal scale.

  12. The changing climate and human vulnerability in north-central Namibia

    Directory of Open Access Journals (Sweden)

    Margaret N. Angula

    2016-01-01

    Full Text Available North-central Namibia is more vulnerable to effects of climate change and variability. Combined effects of environmental degradation, social vulnerability to poverty and a changing climate will compromise subsistence farming in north-central Namibia (NCN. This will make subsistence and small-scale farmers in the region more vulnerable to projected changes in the climate system. Thus, the aim of this article was to examine factors contributing to subsistence farmers’ vulnerability to impacts of climate change. The article further discusses different aspects of human vulnerability and existing adaptation strategies in response to impacts of climate related disasters experienced over the past three to four decades in NCN. Qualitative and quantitative research approaches and methodology were employed to obtain information from subsistence farmers in north-central Namibia. The sociodemographic characteristics of Ohangwena, Oshana and Omusati Region reveals high levels of unemployment, high adult and elderly population and high dependency on agricultural livelihood system. These indicators help understand levels of household vulnerability. The study concludes that households interviewed revealed low levels of adaptive capacity due to exposure to climate risks and combined effects of social, political and cultural factors. This article provided an understanding that is required to inform the adaptation pathways relevant for NCN.

  13. Genetic and morphological divergence among Cooper's Hawk (Accipiter cooperii) populations breeding in north-central and western North America

    Science.gov (United States)

    Sonsthagen, Sarah A.; Rosenfield, Robert N.; Bielefeldt, John; Murphy, Robert K.; Stewart, Andrew C.; Stout, William C.; Driscoll, Timothy G.; Bozek, Michael A.; Sloss, Brian L.; Talbot, Sandra L.

    2012-01-01

    Cooper's Hawk (Accipiter cooperii) populations breeding in the northern portion of the species' range exhibit variation in morphological traits that conforms to predictions based on differences in prey size, tree stand density, and migratory behavior. We examined genetic structure and gene flow and compared divergence at morphological traits (PST) and genetic markers (FST) to elucidate mechanisms (selection or genetic drift) that promote morphological diversification among Cooper's Hawk populations. Cooper's Hawks appear to conform to the genetic pattern of an east-west divide. Populations in British Columbia are genetically differentiated from north-central populations (Wisconsin, Minnesota, and North Dakota; pairwise microsatellite FST= 0.031-0.050; mitochondrial DNA ΦST = 0.177-0.204), which suggests that Cooper's Hawks were restricted to at least two Pleistocene glacial refugia. The strength of the Rocky Mountains—Great Plains area as a barrier to dispersal is further supported by restricted gene-flow rates between British Columbia and other sampled breeding populations. Divergence in morphological traits (PST) was also observed across study areas, but with British Columbia and North Dakota differentiated from Wisconsin and Minnesota, a pattern not predicted on the basis of FST and ΦST interpopulation estimates. Comparison of PSTand FSTestimates suggests that heterogeneous selection may be acting on Cooper's Hawks in the northern portion of their distribution, which is consistent with hypotheses that variation in prey mass and migratory behavior among populations may be influencing overall body size and wing chord. We were unable to distinguish between the effects of genetic drift and selection on tail length in the study populations.

  14. Herbarium specimens reveal the footprint of climate change on flowering trends across north-central North America.

    Science.gov (United States)

    Calinger, Kellen M; Queenborough, Simon; Curtis, Peter S

    2013-08-01

    Shifting flowering phenology with rising temperatures is occurring worldwide, but the rarity of co-occurring long-term observational and temperature records has hindered the evaluation of phenological responsiveness in many species and across large spatial scales. We used herbarium specimens combined with historic temperature data to examine the impact of climate change on flowering trends in 141 species collected across 116,000 km(2) in north-central North America. On average, date of maximum flowering advanced 2.4 days °C(-1), although species-specific responses varied from - 13.5 to + 7.3 days °C(-1). Plant functional types exhibited distinct patterns of phenological responsiveness with significant differences between native and introduced species, among flowering seasons, and between wind- and biotically pollinated species. This study is the first to assess large-scale patterns of phenological responsiveness with broad species representation and is an important step towards understanding current and future impacts of climate change on species performance and biodiversity. PMID:23786499

  15. Glycerol dialkyl glycerol tetraethers and TEX86 index in sinking particles in the western North Pacific

    OpenAIRE

    Yamamoto, Masanobu; Shimamoto, Akifumi; Fukuhara, Tatsuo; Tanaka, Yuichiro; Ishizaka, Joji

    2012-01-01

    Seasonal and depth variation in the flux of glycerol dialkyl glycerol tetraethers (GDGTs) and TEX86 (TEXH86 and TEXL86) values in sinking particles was examined by conducting a 21 month time-series sediment trap experiment at a mooring station (WCT-2, 39°N, 147°E) in the mid-latitude NW Pacific. The aim was to understand the sinking process of GDGTs in the water column and the preservation of the TEX86 signal in the water column and sediment surface. In the shallow trap, the sinking flux of G...

  16. Sulphur compounds, methane, and phytoplankton: interactions along a north-south transit in the western Pacific Ocean

    Directory of Open Access Journals (Sweden)

    C. Zindler

    2012-10-01

    Full Text Available Here we present results of the first comprehensive study of sulphur compounds and methane in the oligotrophic tropical West Pacific Ocean. The concentrations of dimethylsuphide (DMS, dimethylsulphoniopropionate (DMSP, dimethylsulphoxide (DMSO, and methane (CH4, as well as various phytoplankton marker pigments in the surface ocean were measured along a north-south transit from Japan to Australia in October 2009. DMS (0.9 nmol l−1, dissolved DMSP (DMSPd, 1.6 nmol l−1 and particulate DMSP (DMSPp, 2 nmol l−1 concentrations were generally low, while dissolved DMSO (DMSOd, 4.4 nmol l−1 and particulate DMSO (DMSOp, 11.5 nmol l−1 concentrations were comparably enhanced. Positive correlations were found between DMSO and DMSP as well as DMSP and DMSO with chlorophyll a, which suggests a similar source for both compounds. Similar phytoplankton groups were identified as being important for the DMSO and DMSP pool, thus, the same algae taxa might produce both DMSP and DMSO. In contrast, phytoplankton seemed to play only a minor role for the DMS distribution in the western Pacific Ocean. The observed DMSPp : DMSOp ratios were very low and seem to be characteristic of oligotrophic tropical waters representing the extreme endpoint of the global DMSPp : DMSOp ratio vs. SST relationship. It is most likely that nutrient limitation and oxidative stress in the tropical West Pacific Ocean triggered enhanced DMSO production leading to an accumulation of DMSO in the sea surface. Positive correlations between DMSPd and CH4, as well as between DMSO (particulate and total and CH4, were found along the transit. We conclude that both DMSP and DMSO serve as substrates for methanogenic bacteria in the western Pacific Ocean.

  17. 77 FR 8759 - International Fisheries; Western and Central Pacific Fisheries for Highly Migratory Species...

    Science.gov (United States)

    2012-02-15

    ..., Howland Island, Johnston Atoll, Wake Island, and Midway Atoll), must submit a transshipment logbook..., NMFS, Pacific Islands Regional Office (PIRO), 1601 Kapiolani Blvd., Suite 1110, Honolulu, HI 96814-4700... Adobe PDF file formats only. An initial regulatory flexibility analysis (IRFA) prepared under...

  18. Effect of biomass burning over the western North Pacific Rim: wintertime maxima of anhydrosugars in ambient aerosols from Okinawa

    Science.gov (United States)

    Zhu, C.; Kawamura, K.; Kunwar, B.

    2015-02-01

    Biomass burning (BB) largely modifies the chemical composition of atmospheric aerosols on the globe. We collected aerosol samples (TSP) at Cape Hedo, on subtropical Okinawa Island, from October 2009 to February 2012 to study anhydrosugars as BB tracers. Levoglucosan was detected as the dominant anhydrosugar followed by its isomers, mannosan and galactosan. We found a clear seasonal trend of levoglucosan and mannosan with winter maxima and summer minima. Positive correlation was found between levoglucosan and nss-K+ (r = 0.38, p levoglucosan / mannosan ratios were lower (2.1-4.8) in May-June and higher (13.3-13.9) in November-December. The lower values may be associated with softwood burning in northern China, Korea and southwestern Japan whereas the higher values are probably caused by agricultural waste burning of maize straw in the North China Plain. Anhydrosugars comprised 0.22% of water-soluble organic carbon (WSOC) and 0.13% of organic carbon (OC). The highest values to WSOC (0.37%) and OC (0.25%) were found in winter, again indicating an important BB contribution to Okinawa aerosols in winter. This study provides useful information to better understand the effect of East Asian biomass burning on the air quality in the western North Pacific Rim.

  19. Species composition and diversity of pelagic fishes based on a longline fishery catch in the North Pacific Ocean

    Institute of Scientific and Technical Information of China (English)

    ZHU Jiangfeng; DAI Xiaojie; CHEN Yong

    2011-01-01

    Evaluation of spatial-temporal variability of species composition and diversity in oceanic ecosystems is not easy because it is usually difficult to obtain sufficient data quantifying such variability.In this study, we examined pelagic species diversity indicators, species richness, Shannon-Wiener index of diversity and Hurlbert's species evenness, for fish assemblages from two areas (north and south) in the North Pacific Ocean (2°-12°N, 178°E-165°W) during May-July 2008. The assemblages were based on data collected by an onboard scientific observer during a commercial longline fishing trip. The species richness and Shannon-Wiener diversity index of fish assemblages in the northern area were slightly higher than those in the southern area, although these differences were not significant (t test,P>0.05). Non-parametric multidimensional scaling and analysis of similarities indicated that there were significant differences in fish assemblages between the two areas (P<0.01).

  20. The importance of genetic verification for determination of Atlantic salmon in north Pacific waters

    Science.gov (United States)

    Nielsen, J.L.; Williams, I.; Sage, G.K.; Zimmerman, C.E.

    2003-01-01

    Genetic analyses of two unknown but putative Atlantic salmon Salmo salar captured in the Copper River drainage, Alaska, demonstrated the need for validation of morphologically unusual fishes. Mitochondrial DNA sequences (control region and cytochrome b) and data from two nuclear genes [first internal transcribed spacer (ITS-1) sequence and growth hormone (GH1) amplification product] indicated that the fish caught in fresh water on the Martin River was a coho salmon Oncorhynchus kisutch, while the other fish caught in the intertidal zone of the Copper River delta near Grass Island was an Atlantic salmon. Determination of unusual or cryptic fish based on limited physical characteristics and expected seasonal spawning run timing will add to the controversy over farmed Atlantic salmon and their potential effects on native Pacific species. It is clear that determination of all putative collections of Atlantic salmon found in Pacific waters requires validation. Due to uncertainty of fish identification in the field using plastic morphometric characters, it is recommended that genetic analyses be part of the validation process. ?? 2003 The Fisheries Society of the British Isles.