Now showing items 9-28 of 921

    • Advances in measurements of particle cycling and fluxes in the ocean 

      Owens, Stephanie A. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2013-02)
      The sinking flux of particles is an important removal mechanism of carbon from the surface ocean as part of the biological pump and can play a role in cycling of other chemical species. This work dealt with improving ...
    • Aging of marine organic matter during cross-shelf lateral transport in the Benguela upwelling system revealed by compound-specific radiocarbon dating 

      Mollenhauer, Gesine; Inthorn, Maik; Vogt, Thomas; Zabel, Matthias; Sinninghe Damste, Jaap S.; Eglinton, Timothy I. (American Geophysical Union, 2007-09-18)
      Organic matter accumulation and burial on the Namibian shelf and upper slope are spatially heterogeneous and strongly controlled by lateral transport in subsurface nepheloid layers. Much of the material deposited in ...
    • Air-sea CO2 flux in the Pacific Ocean for the period 1990–2009 

      Ishii, Masao; Feely, Richard A.; Rodgers, Keith B.; Park, Geun-Ha; Wanninkhof, Rik; Sasano, D.; Sugimoto, H.; Cosca, C. E.; Nakaoka, Shin-ichiro; Telszewski, Maciej; Nojiri, Yukihiro; Mikaloff Fletcher, Sara E.; Niwa, Y.; Patra, Prabir K.; Valsala, V.; Nakano, Hideyuki; Lima, Ivan D.; Doney, Scott C.; Buitenhuis, Erik T.; Aumont, Olivier; Dunne, John P.; Lenton, A.; Takahashi, Taro (Copernicus Publications on behalf of the European Geosciences Union, 2014-02-06)
      Air–sea CO2 fluxes over the Pacific Ocean are known to be characterized by coherent large-scale structures that reflect not only ocean subduction and upwelling patterns, but also the combined effects of wind-driven gas ...
    • Air-sea CO2 fluxes and the controls on ocean surface pCO2 seasonal variability in the coastal and open-ocean southwestern Atlantic Ocean : a modeling study 

      Arruda, R.; Calil, P. H. R.; Bianchi, A. A.; Doney, Scott C.; Gruber, Nicolas; Lima, Ivan D.; Turi, G. (Copernicus Publications on behalf of the European Geosciences Union, 2015-10-12)
      We use an eddy-resolving, regional ocean biogeochemical model to investigate the main variables and processes responsible for the climatological spatio-temporal variability of pCO2 and the air-sea CO2 fluxes in the ...
    • Air-sea gas transfer : its dependence on wind stress, small-scale roughness, and surface films 

      Frew, Nelson M.; Bock, Erik J.; Schimpf, Uwe; Hara, Tetsu; Haußecker, Horst; Edson, James B.; McGillis, Wade R.; Nelson, Robert K.; McKenna, Sean P.; Uz, B. Mete; Jahne, B. (American Geophysical Union, 2004-08-21)
      The influence of wind stress, small-scale waves, and surface films on air-sea gas exchange at low to moderate wind speeds (<10 m s−1) is examined. Coincident observations of wind stress, heat transfer velocity, surface ...
    • Air-sea gas transfer velocity estimates from the Jason-1 and TOPEX altimeters : prospects for a long-term global time series 

      Glover, David M.; Frew, Nelson M.; McCue, Scott J. (2006-03-02)
      Estimation of global and regional air–sea fluxes of climatically important gases is a key goal of current climate research programs. Gas transfer velocities needed to compute these fluxes can be estimated by combining ...
    • Alkenone distribution in Lake Van sediment over the last 270 ka : influence of temperature and haptophyte species composition 

      Randlett, Marie-Eve; Coolen, Marco J. L.; Stockhecke, Mona; Pickarski, Nadine; Litt, Thomas; Balkema, Cherel; Kwiecien, Ola; Tomonaga, Yama; Wehrli, Bernhard; Schubert, Carsten J. (Elsevier, 2014-07-29)
      Fossil long-chain alkenones have been used for several decades to reconstruct past ocean surface water temperatures and gained recent interest as a paleotemperature proxy for continental lake settings. However, factors ...
    • Analysis of high-precision vanadium isotope ratios by medium resolution MC-ICP-MS 

      Nielsen, Sune G.; Owens, Jeremy D.; Horner, Tristan J. (2015-11)
      We present and verify a new method to measure vanadium isotope ratios using a Thermo Scientific Neptune multi-collector inductively-coupled plasma mass spectrometer (MCICP- MS) operated in medium mass resolution mode. ...
    • Analysis of unresolved complex mixtures of hydrocarbons extracted from Late Archean sediments by comprehensive two-dimensional gas chromatography (GC×GC) 

      Ventura, Gregory T.; Kenig, Fabien; Reddy, Christopher M.; Frysinger, Glenn S.; Nelson, Robert K.; Van Mooy, Benjamin A. S.; Gaines, Richard B. (2008-03)
      Hydrocarbon mixtures too complex to resolve by traditional capillary gas chromatrography display gas chromatograms with dramatically rising baselines or “humps” of coeluting compounds that are termed unresolved complex ...
    • Ancient DNA derived from alkenone-biosynthesizing haptophytes and other algae in Holocene sediments from the Black Sea 

      Coolen, Marco J. L.; Boere, Arjan C.; Abbas, Ben; Baas, Marianne; Wakeham, Stuart G.; Sinninghe Damste, Jaap S. (American Geophysical Union, 2006-02-18)
      Holocene sea surface temperatures (SST) of the Black Sea have been reconstructed using sedimentary C37 unsaturated alkenones assumed to be derived from the coccolithophorid haptophyte Emiliania huxleyi, whose fossil ...
    • Ancient DNA techniques : applications for deep-water corals 

      Waller, Rhian G.; Adkins, Jess F.; Robinson, Laura F.; Shank, Timothy M. (University of Miami - Rosenstiel School of Marine and Atmospheric Science, 2007-11-01)
      The potential applications of ancient DNA (aDNA) techniques have been realized relatively recently, and have been revolutionized by the advent of pCR techniques in the mid 1980s. Although these techniques have been proven ...
    • And on top of all that… coping with ocean acidification in the midst of many stressors 

      Breitburg, Denise L.; Salisbury, Joseph E.; Bernhard, Joan M.; Cai, Wei-Jun; Dupont, Sam; Doney, Scott C.; Kroeker, Kristy J.; Levin, Lisa A.; Long, W. Christopher; Milke, Lisa M.; Miller, Seth H.; Phelan, Beth; Passow, Uta; Seibel, Brad A.; Todgham, Anne E.; Tarrant, Ann M. (The Oceanography Society, 2015-06)
      Oceanic and coastal waters are acidifying due to processes dominated in the open ocean by increasing atmospheric CO2 and dominated in estuaries and some coastal waters by nutrient-fueled respiration. The patterns and ...
    • Animating the carbon cycle 

      Schmitz, Oswald J.; Raymond, Peter A.; Estes, James A.; Kurz, Werner A.; Holtgrieve, Gordon W.; Ritchie, Mark E.; Schindler, Daniel E.; Spivak, Amanda C.; Wilson, Rod W.; Bradford, Mark A.; Christensen, Villy; Deegan, Linda A.; Smetacek, Victor; Vanni, Michael J.; Wilmers, Christopher C. (2013-08)
      Understanding the biogeochemical processes regulating carbon cycling is central to mitigating atmospheric CO2 emissions. The role of living organisms has been accounted for, but the focus has traditionally been on ...
    • The annual cycle of gross primary production, net community production, and export efficiency across the North Pacific Ocean 

      Palevsky, Hilary I.; Quay, Paul D.; Lockwood, Deirdre E.; Nicholson, David P. (John Wiley & Sons, 2016-02-27)
      We measured triple oxygen isotopes and oxygen/argon dissolved gas ratios as nonincubation-based geochemical tracers of gross oxygen production (GOP) and net community production (NCP) on 16 container ship transects across ...
    • Annual cycles of ecological disturbance and recovery underlying the subarctic Atlantic spring plankton bloom 

      Behrenfeld, Michael J.; Doney, Scott C.; Lima, Ivan D.; Boss, Emmanuel S.; Siegel, David A. (John Wiley & Sons, 2013-06-20)
      Satellite measurements allow global assessments of phytoplankton concentrations and, from observed temporal changes in biomass, direct access to net biomass accumulation rates (r). For the subarctic Atlantic basin, analysis ...
    • Anthropogenic disturbance of element cycles at the Earth’s surface 

      Sen, Indra S.; Peucker-Ehrenbrink, Bernhard (2012-07)
      The extent to which humans are modifying Earth’s surface chemistry can be quantified by comparing total anthropogenic element fluxes with their natural counterparts (Klee & Graedel, 2004). We quantify anthropogenic mass ...
    • Anthropogenic ocean acidification over the twenty-first century and its impact on calcifying organisms 

      Orr, James C.; Fabry, Victoria J.; Aumont, Olivier; Bopp, Laurent; Doney, Scott C.; Feely, Richard A.; Gnanadesikan, Anand; Gruber, Nicolas; Ishida, Akio; Joos, Fortunat; Key, Robert M.; Lindsay, Keith; Maier-Reimer, Ernst; Matear, Richard J.; Monfray, Patrick; Mouchet, Anne; Najjar, Raymond G.; Plattner, Gian-Kasper; Rodgers, Keith B.; Sabine, Christopher L.; Sarmiento, Jorge L.; Schlitzer, Reiner; Slater, Richard D.; Totterdell, Ian J.; Weirig, Marie-France; Yamanaka, Yasuhiro; Yool, Andrew (2005-07-29)
      The surface ocean is everywhere saturated with respect to calcium carbonate (CaCO3). Yet increasing atmospheric CO2 reduces ocean pH and carbonate ion concentrations [CO32−] and thus the level of saturation. Reduced ...
    • Anticipating ocean acidification's economic consequences for commercial fisheries 

      Cooley, Sarah R.; Doney, Scott C. (2009-05)
      Ocean acidification, a consequence of rising anthropogenic CO2 emissions, is poised to change marine ecosystems profoundly by increasing dissolved CO2 and decreasing ocean pH, carbonate concentration, and calcium carbonate ...
    • Apparent oxygen utilization rates calculated from tritium and helium-3 profiles at the Bermuda Atlantic Time-series Study site 

      Stanley, Rachel H. R.; Doney, Scott C.; Jenkins, William J.; Lott, Dempsey E. (Copernicus Publications on behalf of the European Geosciences Union., 2012-06-04)
      We present three years of Apparent Oxygen Utilization Rates (AOUR) estimated from oxygen and tracer data collected over the ocean thermocline at monthly resolution between 2003 and 2006 at the Bermuda Atlantic Time-series ...
    • Applications of fluorescence spectroscopy to environmental chemistry 

      Green, Sarah A. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1992-02)
      The work presented in this thesis consists of three parts. The first is a photophysical study of the mechanism of fluorescence quenching by stable nitroxyl radicals, which are becoming an important analytical tool for ...