Southern Ocean control on the extent of denitrification in the southeast Pacific over the last 70 ka |
| |
| Affiliation: | 1. Princeton Environmental Institute and Department of Geosciences, Princeton University, Princeton, NJ, USA;2. College of Oceanic and Atmospheric Sciences, Oregon State University, Corvallis, OR, USA;3. Département de Géologie et Océanographie, Université Bordeaux I, UMR CNRS 5805 EPOC, avenue des facultés, 33405 Talence cedex, France;1. Godwin Laboratory for Palaeoclimate Research, Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ, UK;2. Department of Geological Sciences and INSTAAR, University of Colorado, Boulder, CO, 80309, USA;1. Department of Oceanography, Texas A&M University, College Station, TX 77843, USA;2. Department of Marine Science, University of Connecticut, Groton, CT 06340, USA;3. Department of Ocean, Earth, and Atmospheric Sciences, Old Dominion University, Norfolk, VA 23529, USA;4. Department of Geological Sciences, University of Florida, Gainesville, FL 32611, USA;5. Global Aquatic Research LLC, Sodus, NY 14551, USA;6. Department of Geology and Geophysics, Texas A&M University, College Station, TX 77843, USA;1. Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, 360 Woods Hole Road, MA 02543, Woods Hole, USA;2. Renard Centre of Marine Geology, Ghent University, Krijgslaan 281 S8, 9000, Gent, Belgium;3. Department of Geological Sciences and Institute of Arctic and Alpine Research (INSTAAR), University of Colorado Boulder, 450 UCB, Boulder, CO 80309, USA;4. Department of Oceanography and COPAS-Sur Austral Program, University of Concepción, Barrio Universitario s/n, Concepción, Chile;1. Department of Geography, Durham University, South Road, Durham DH1 3LE, UK;2. School of Geography Planning and Environmental Management, University of Queensland, Brisbane, QLD 4072, Australia;1. Stanford University, Department of Environmental Earth System Science, Stanford, CA 94305, USA;2. MIT/WHOI Joint Program in Chemical Oceanography, Woods Hole, MA 02543, USA;3. Woods Hole Oceanographic Institution, Department of Marine Chemistry and Geochemistry, Woods Hole, MA 02543, USA;1. Godwin Laboratory for Palaeoclimate Research, Department of Earth Sciences, University of Cambridge, Cambridge CB2 3EQ, UK;2. LSCE/IPSL Laboratoire, CNRS–CEA–UVSQ, 91198 Gif-sur-Yvette, France |
| |
| Abstract: | Temporal changes in oceanic denitrification, the bacterial reduction of nitrate under suboxic conditions, highlight the potential importance of N inventory changes and the production of N2O on the climate system. At the same time, the cause of the globally observed variation in denitrification remains unclear. High-resolution benthic foraminiferal oxygen isotope and bulk sediment nitrogen isotope records from ODP Site 1234 on the Chile Margin record integrated denitrification changes within the Peru–Chile Upwelling system over the last ∼70 ka. Denitrification changes in the southeast Pacific are coherent with Antarctic climate changes recorded by the Byrd ice core δ18O record, and lead northern hemisphere climate events. The southern-hemisphere character of the Chile margin δ15N record suggests that episodes of reduced denitrification in the SE Pacific represent times when more oxygen was supplied as the result of changes in the ventilation and preformed nutrient content of Subantarctic Mode Water (SAMW), which forms in the Subantarctic zone of the Southern Ocean and feeds into the low-latitude thermocline. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
