Now showing items 492-511 of 769

  • Natural variability in a stable, 1000-yr global coupled climate-carbon cycle simulation 

    Doney, Scott C.; Lindsay, Keith; Fung, Inez Y.; John, Jasmin (American Meteorological Society, 2006-07-01)
    A new 3D global coupled carbon–climate model is presented in the framework of the Community Climate System Model (CSM-1.4). The biogeochemical module includes explicit land water–carbon coupling, dynamic carbon allocation ...
  • Nature, origin, transport and deposition of andosol parent material in south-central Chile (36-42°S) 

    Bertrand, Sebastien; Fagel, Nathalie (2007-07)
    The andosols of south-central Chile (36-42°S) are developed on yellow-brown loams that cover the region with a thickness of several meters. In the literature, several hypotheses concerning the nature, origin, mode of ...
  • Net atmospheric mercury deposition to Svalbard : estimates from lacustrine sediments 

    Drevnick, Paul E.; Yang, Handong; Lamborg, Carl H.; Rose, Neil L. (2012-05)
    In this study we used lake sediments, which faithfully record Hg inputs, to derive estimates of net atmospheric Hg deposition to Svalbard, Norwegian Arctic. With the exception of one site affected by local pollution, ...
  • Net community production and gross primary production rates in the western equatorial Pacific 

    Stanley, Rachel H. R.; Kirkpatrick, John B.; Cassar, Nicolas; Barnett, Bruce A.; Bender, Michael L. (American Geophysical Union, 2010-10-12)
    Net community production (NCP) and gross primary production (GPP) are two key metrics for quantifying the biological carbon cycle. In this study, we present a detailed characterization of NCP and GPP in the western equatorial ...
  • A new approach to estimation of global air-sea gas transfer velocity fields using dual-frequency altimeter backscatter 

    Frew, Nelson M.; Glover, David M.; Bock, Erik J.; McCue, Scott J. (American Geophysical Union, 2007-11-03)
    A new approach to estimating air-sea gas transfer velocities based on normalized backscatter from the dual-frequency TOPEX and Jason-1 altimeters is described. The differential scattering of Ku-band (13.6 GHz) and C-band ...
  • 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 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 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 ...