TY - JOUR
T1 - Nitrogen isotopic variations in the Gulf of California since the Last Deglaciation
T2 - Response to global climate change
AU - Pride, Carol
AU - Thunell, Robert
AU - Sigman, Daniel
AU - Keigwin, Lloyd
AU - Altabet, Mark
AU - Tappa, Eric
N1 - Funding Information:
We thank the director and crew of B/O El Puma, the director and staff of the Centro Regional de Investigacion Pesquera, the staff of the Centro de Investigaciones Biologicas, and the crews of BIP XI and Atlantis II for their assistance in coring and maintaining the sediment trapping program. We appreciate the valuable reviews contributed by A. Van Geen and one anonymous reviewer. We would also like to acknowledge J. Pike and A. Kemp for sharing their detailed core description of JPC-56. This research was supported in part by NSF Grants OCE-9301413, OCE-8917699, OCE-9201255, OCE-9526356 (MAA), and OPP-9530714 (MAA). Radiocarbon dating and δ18O analyses were supported by an NSF grant to L.Keigwin. C. Pride''s research was performed under appointment to the Graduate Fellowships for Global Change program administered by Oak Ridge Associated Universities for the U.S. Department of Energy, Office of Health and Environmental Research, Atmospheric and Climate Research Division. Data archived at the World Data Center-A for Paleoclimatology, NOAA-NGDC, 325 Broadway, Boulder, Colorado (e-mail: paleo@mail.ngdc.noa.gov; URL: http://www.ngdc.noaa.gov/paleo).
Publisher Copyright:
Copyright 1999 by the American Geophysical Union.
PY - 1999/6
Y1 - 1999/6
N2 - High-resolution records of the nitrogen isotopic composition of organic matter (δ15Norg), opal content, and opal accumulation rates from the central Gulf of California reveal large and abrupt variations during deglaciation and gradual Holocene changes coincident with climatic changes recorded in the North Atlantic. Homogenous sediments with relatively low δ15Norg values and low opal content were deposited at the end of the last glacial period, during the Younger-Dryas event, and during the middle to late Holocene. In contrast, laminated sediments deposited in the two deglacial stages are characterized by very high δ15Norg values (>14‰) and opal accumulation rates (29-41 mg cm-2 yr-1). Abrupt shifts in δ15Norg were driven by widespread changes in the extent of suboxic subsurface waters supporting denitrification and were amplified in the central gulf record due to variations in upwelling, vertical mixing, and/or the latitudinal position of the Intertropical Convergence Zone.
AB - High-resolution records of the nitrogen isotopic composition of organic matter (δ15Norg), opal content, and opal accumulation rates from the central Gulf of California reveal large and abrupt variations during deglaciation and gradual Holocene changes coincident with climatic changes recorded in the North Atlantic. Homogenous sediments with relatively low δ15Norg values and low opal content were deposited at the end of the last glacial period, during the Younger-Dryas event, and during the middle to late Holocene. In contrast, laminated sediments deposited in the two deglacial stages are characterized by very high δ15Norg values (>14‰) and opal accumulation rates (29-41 mg cm-2 yr-1). Abrupt shifts in δ15Norg were driven by widespread changes in the extent of suboxic subsurface waters supporting denitrification and were amplified in the central gulf record due to variations in upwelling, vertical mixing, and/or the latitudinal position of the Intertropical Convergence Zone.
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U2 - 10.1029/1999PA900004
DO - 10.1029/1999PA900004
M3 - Article
AN - SCOPUS:0032825094
SN - 0883-8305
VL - 14
SP - 397
EP - 409
JO - Paleoceanography
JF - Paleoceanography
IS - 3
ER -