FN Archimer Export Format
PT J
TI Bottom water variability in the subtropical northwestern Pacific from 26 kyr BP to present based on Mg/Ca and stable carbon and oxygen isotopes of benthic foraminifera
BT 
AF KUBOTA, Y.
   KIMOTO, K.
   ITAKI, T.
   YOKOYAMA, Y.
   MIYAIRI, Y.
   MATSUZAKI, H.
AS 1:1,2;2:2;3:3;4:4,5;5:4;6:6;
FF 1:;2:;3:;4:;5:;6:;
C1 Natl Museum Nat & Sci, Dept Geol & Paleontol, Tsukuba, Ibaraki 3050005, Japan.
   Japan Agcy Marine Earth Sci & Technol, Res Inst Global Change, Yokosuka, Kanagawa 2370061, Japan.
   Natl Inst Adv Ind Sci & Technol, Geol Survey Japan, Tsukuba, Ibaraki 3058567, Japan.
   Univ Tokyo, Atmosphere & Ocean Res Inst, Kashiwa, Chiba 2778564, Japan.
   Japan Agcy Marine Earth Sci & Technol, Dept Biogeochem, Yokosuka, Kanagawa 2370061, Japan.
   Univ Tokyo, Dept Nucl Engn & Management, Bunkyo Ku, Tokyo 1130032, Japan.
C2 NATL MUSEUM NAT & SCI, JAPAN
   JAMSTEC, JAPAN
   GEOL SURVEY JAPAN AIST, JAPAN
   UNIV TOKYO, JAPAN
   JAMSTEC, JAPAN
   UNIV TOKYO, JAPAN
IN DOAJ
IF 3.638
TC 19
UR https://archimer.ifremer.fr/doc/00352/46289/45950.pdf
   https://archimer.ifremer.fr/doc/00352/46289/45951.pdf
LA English
DT Article
CR MD 122 / WEPAMA
BO Marion Dufresne
AB To understand bottom water variability in the subtropical northwestern Pacific, bottom water temperatures (BWTs), carbon isotopes (delta C-13), and oxygen isotopes of seawater (delta O-18(w)) at a water depth of 1166 m were reconstructed from 26 kyr BP to present. A new regional Mg / Ca calibration for the benthic foraminifera Cibicidoides wuellerstorfi (type B) was established to convert the benthic Mg / Ca value to BWT, based on 26 surface sediment samples and two core-top samples retrieved around Okinawa Island. During the Last Glacial Maximum (LGM), the delta O-18(w) in the intermediate water in the northwestern South Pacific was similar to 0.4 parts per thousand lower than in the deep South Pacific, indicating a greater vertical salinity gradient than at present. This salinity (and probably density) structure would have led to stratification in the intermediate and deep Pacific, which would, in turn, have greatly influenced carbon storage during the glacial time. The benthic Mg / Ca and delta O-18(w) records suggest changes that seem to follow Heinrich event 1 (H1) and the Bolling-Alleod (B/A) and Younger Dryas (YD) intervals, with BWT higher during H1 (similar to 17 kyr BP) and YD (similar to 12 kyr BP) and lower during B/A (similar to 14 kyr BP). The warming in the bottom water during H1 suggests increased contribution of North Pacific Intermediate Water (NPIW) to the subtropical northwestern Pacific and decreased upwelling of cooler waters from the abyssal North Pacific. During the interval from 17 to 14.5 kyr BP, the BWT tended to decrease successively in association with a decrease in delta C-13 values, presumably as a result of increased upwelling of the abyssal waters to the intermediate depths of the North Pacific caused by shoaling and enhancement of the southward return flow of Pacific Deep Water (PDW). During the Holocene, the millennial- to sub-millennial-scale variations in the BWT generally correlate with the sea surface temperatures in the Okhotsk Sea, the source region of the NPIW, suggesting that changes in the BWT are linked to changes in the NPIW production rate.
PY 2015
SO Climate Of The Past
SN 1814-9324
PU Copernicus Gesellschaft Mbh
VL 11
IS 6
UT 000357119900002
BP 803
EP 824
DI 10.5194/cp-11-803-2015
ID 46289
ER

EF