Now showing items 532-551 of 838

  • A new automated method for measuring noble gases and their isotopic ratios in water samples 

    Stanley, Rachel H. R.; Baschek, Burkard; Lott, Dempsey E.; Jenkins, William J. (American Geophysical Union, 2009-05-29)
    A method is presented for precisely measuring all five noble gases and their isotopic ratios in water samples using multiple programmed multistage cryogenic traps in conjunction with quadrupole mass spectrometry and magnetic ...
  • A new database to explore the findings from large-scale ocean iron enrichment experiments 

    Boyd, Philip W.; Bakker, Dorothee C. E.; Chandler, Cynthia L. (The Oceanography Society, 2012-12)
    Some of the largest scientific manipulation experiments conducted on our planet have enriched broad swaths of the surface ocean with iron. Surface ocean signatures of these iron enrichment experiments have covered areas ...
  • A new Holocene eruptive history of Erebus volcano, Antarctica using cosmogenic 3He and 36Cl exposure ages 

    Parmelee, David E. F.; Kyle, Philip R.; Kurz, Mark D.; Marrero, Shasta M.; Phillips, Fred M. (Elsevier, 2015-09-05)
    The ages of recent effusive eruptions on Erebus volcano, Antarctica are poorly known. Published 40Ar/39Ar ages of the 10 youngest “post-caldera” lava flows are unreliable because of the young ages of the flows (<10 ka) and ...
  • A new method for the determination of low-level actinium-227 in geological samples 

    Dulaiova, Henrieta; Sims, Kenneth W. W.; Charette, Matthew A.; Prytulak, Julie; Blusztajn, Jerzy S. (2012-07-31)
    We developed a new method for the determination of 227Ac in geological samples. The method uses extraction chromatographic techniques and alpha-spectrometry and is applicable for a range of natural matrices. Here we report ...
  • A new method for the estimation of sinking particle fluxes from measurements of the particle size distribution, average sinking velocity, and carbon content 

    McDonnell, Andrew M. P.; Buesseler, Ken O. (Association for the Sciences of Limnology and Oceanography, 2012-05)
    We describe a new method for estimating sinking particulate carbon fluxes at high spatial and temporal resolutions from measurements of the particle concentration size distribution taken with an in situ camera system, in ...
  • New perspectives on radium behavior within a subterranean estuary 

    Gonneea, Meagan E.; Morris, Paul J.; Dulaiova, Henrieta; Charette, Matthew A. (2007-04-02)
    Over the past decade, radium isotopes have been frequently applied as tracers of submarine groundwater discharge (SGD). The unique radium signature of SGD is acquired within the subterranean estuary, a mixing zone between ...
  • Niche of harmful alga Aureococcus anophagefferens revealed through ecogenomics 

    Gobler, Christopher J.; Berry, Dianna L.; Dyhrman, Sonya T.; Wilhelm, Steven W.; Salamov, Asaf; Lobanov, Alexei V.; Zhang, Yan; Collier, Jackie L.; Wurch, Louie L.; Kustka, Adam B.; Dill, Brian D.; Shah, Manesh; VerBerkmoes, Nathan C.; Kuo, Alan J.; Terry, Astrid; Pangilinan, Jasmyn; Lindquist, Erika A.; Lucas, Susan; Paulsen, Ian T.; Hattenrath-Lehmann, Theresa K.; Talmage, Stephanie C.; Walker, Elyse A.; Koch, Florian; Burson, Amanda M.; Marcoval, Maria Alejandra; Tang, Ying-Zhong; LeCleir, Gary R.; Coyne, Kathryn J.; Berg, Gry M.; Bertrand, Erin M.; Saito, Mak A.; Gladyshev, Vadim N.; Grigoriev, Igor V. (2011-01)
    Harmful algal blooms (HABs) cause significant economic and ecological damage worldwide. Despite considerable efforts, a comprehensive understanding of the factors that promote these blooms has been lacking because the ...
  • Nitrogen cycling in oxygen deficient zones : insights from δ15N and δ18O of nitrite and nitrate 

    Buchwald, Carolyn (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2013-02)
    The stable isotopes, δ15N and δ18O, of nitrite and nitrate can be powerful tools used to interpret nitrogen cycling in the ocean. In order to interpret isotope profiles, the isotope systematics of each process involved ...
  • Nitrogen cycling in the deep sedimentary biosphere : nitrate isotopes in porewaters underlying the oligotrophic North Atlantic 

    Wankel, Scott D.; Buchwald, Carolyn; Ziebis, Wiebke; Wenk, Christine B.; Lehmann, Moritz F. (Copernicus Publications on behalf of the European Geosciences Union, 2015-12-21)
    Nitrogen (N) is a key component of fundamental biomolecules. Hence, its cycling and availability are central factors governing the extent of ecosystems across the Earth. In the organic-lean sediment porewaters underlying ...
  • Nitrogen fixation in the South Atlantic Gyre and the Benguela Upwelling System 

    Sohm, Jill A.; Hilton, Jason A.; Noble, Abigail E.; Zehr, Jonathan P.; Saito, Mak A.; Webb, Eric A. (American Geophysical Union, 2011-08-27)
    Dinitrogen (N2) fixation is recognized as an important input of new nitrogen (N) to the open ocean gyres, contributing to the export of organic matter from surface waters. However, very little N2-fixation research has ...
  • Nitrogen isotopes in chlorophyll and the origin of Eastern Mediterranean sapropels 

    Sachs, Julian P. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1997-02)
    The goals of this thesis were: (1) to establish methods for the determination of nitrogen and carbon isotope ratios in marine particulate and sedimentary chlorophyll derivatives; (2) to establish chlorophyll δ15N and ...
  • Noble gas constraints on air-sea gas exchange and bubble fluxes 

    Stanley, Rachel H. R.; Jenkins, William J.; Lott, Dempsey E.; Doney, Scott C. (American Geophysical Union, 2009-11-19)
    Air-sea gas exchange is an important part of the biogeochemical cycles of many climatically and biologically relevant gases including CO2, O2, dimethyl sulfide and CH4. Here we use a three year observational time series ...
  • Nonequilibrium clumped isotope signals in microbial methane 

    Wang, David T.; Gruen, Danielle S.; Lollar, Barbara Sherwood; Hinrichs, Kai-Uwe; Stewart, Lucy C.; Holden, James F.; Hristov, Alexander N.; Pohlman, John W.; Morrill, Penny L.; Konneke, Martin; Delwiche, Kyle B.; Reeves, Eoghan P.; Sutcliffe, Chelsea N.; Ritter, Daniel J.; Seewald, Jeffrey S.; McIntosh, Jennifer C.; Hemond, Harold F.; Kubo, Michael D.; Cardace, Dawn; Hoehler, Tori M.; Ono, Shuhei (2015-02-09)
    Methane is a key component in the global carbon cycle with a wide range of anthropogenic and natural sources. Although isotopic compositions of methane have traditionally aided source identification, the abundance of its ...
  • North Pacific carbon cycle response to climate variability on seasonal to decadal timescales 

    McKinley, Galen A.; Takahashi, Taro; Buitenhuis, Erik T.; Chai, Fei; Christian, James R.; Doney, Scott C.; Jiang, Mingshun; Lindsay, Keith; Moore, J. Keith; Le Quere, Corinne; Lima, Ivan D.; Murtugudde, Raghu; Shi, L.; Wetzel, P. (American Geophysical Union, 2006-07-04)
    Climate variability drives significant changes in the physical state of the North Pacific, and thus there may be important impacts of climate variability on the upper ocean carbon balance across the basin. We address this ...
  • North-South asymmetry in the modeled phytoplankton community response to climate change over the 21st century 

    Marinov, Irina; Doney, Scott C.; Lima, Ivan D.; Lindsay, Keith; Moore, J. Keith; Mahowald, Natalie M. (John Wiley & Sons, 2013-12-20)
    Here we analyze the impact of projected climate change on plankton ecology in all major ocean biomes over the 21st century, using a multidecade (1880–2090) experiment conducted with the Community Climate System Model ...
  • NotCal04; comparison/ calibration 14C records 26-50 cal kyr BP 

    van der Plicht, Johannes; Beck, J. Warren; Bard, Edouard; Baillie, Mike G. L.; Blackwell, Paul G.; Buck, Caitlin E.; Friedrich, Michael; Guilderson, Thomas P.; Hughen, Konrad A.; Kromer, Bernd; McCormac, F. G.; Ramsey, C. Bronk; Reimer, Paul J.; Reimer, Ron W.; Remmele, Sabine; Richards, D. A.; Southon, John R.; Stuiver, Minze; Weyhenmeyer, Constanze E. (Dept. of Geosciences, University of Arizona, 2004)
    The radiocarbon calibration curve IntCal04 extends back to 26 cal kyr BP. While several high-resolution records exist beyond this limit, these data sets exhibit discrepancies of up to several millennia. As a result, no ...
  • A novel lineage of proteobacteria involved in formation of marine Fe-oxidizing microbial mat communities 

    Emerson, David; Rentz, Jeremy A.; Lilburn, Timothy G.; Davis, Richard E.; Aldrich, Henry; Chan, Clara S.; Moyer, Craig L. (Public Library of Science, 2007-08-01)
    For decades it has been recognized that neutrophilic Fe-oxidizing bacteria (FeOB) are associated with hydrothermal venting of Fe(II)-rich fluids associated with seamounts in the world's oceans. The evidence was based almost ...
  • Nutrient limitation dynamics of a coastal Cape Cod pond : seasonal trends in alkaline phosphatase activity 

    Haupert, Christie L. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2000-11-13)
    A bi-weekly seasonal study was conducted in Ashumet Pond (Cape Cod, Massachusetts). The Redfield Ratio (106C:16N:1P) and alkaline phosphatase activity (APA) were utilized in tandem as nutrient deficiency indicators (NDIs) ...
  • Nutrition and income from molluscs today imply vulnerability to ocean acidification tomorrow 

    Cooley, Sarah R.; Lucey, Noelle; Kite-Powell, Hauke L.; Doney, Scott C. (2011-05-20)
    Atmospheric carbon dioxide (CO2) emissions from human industrial activities are causing a progressive alteration of seawater chemistry, termed ocean acidification, that has decreased seawater pH and carbonate ion ...
  • Observations of carbon export by small sinking particles in the upper mesopelagic 

    Durkin, Colleen A.; Estapa, Margaret L.; Buesseler, Ken O. (Elsevier, 2015-02-27)
    Carbon and nutrients are transported out of the surface ocean and sequestered at depth by sinking particles. Sinking particle sizes span many orders of magnitude and the relative influence of small particles on carbon ...