Abstract
To understand Holocene climate evolutions in low-latitude region of the western Pacific, paired δ18O and Mg/Ca records of planktonic foraminifer Globigerinoides ruber (250-300μm, sensu stricto, s.s.) from a marine core ORI715-21 (121.5°E, 22.7°N, water depth 760m) underneath the Kuroshio Current (KC) off eastern Taiwan were analyzed. Over the past 7500years, the geochemical proxy-inferred sea surface temperature (SST) hovered around 27-28°C and seawater δ18O (δ18OW) slowly decreased 0.2-0.4‰ for two KC sites at 22.7° and 25.3°N. Comparison with a published high-SST and high-salinity equatorial tropical Pacific record, MD98-2181 located at the Mindanao Current (MC) at 6.3°N, reveals an anomalous time interval at 3.5-1.5kyr ago (before 1950 AD). SST gradient between the MC site and two KC site decrease from 1.5-2.0°C to only 0-1°C, and δ18OW from 0.1-0.3‰ to 0‰ for this 2-kyr time window. The high SST and low gradient could result from a northward shift of the North Equatorial Current, which implies a weakened KC. The long-term descending δ18OW and increasing precipitation in the entire low-latitude western Pacific and the gradually decreasing East Asian summer monsoonal rainfall during middle-to-late Holocene is likely caused by different land and ocean responses to solar insolation and/or enhanced moisture transportation from the Atlantic to Pacific associated with the southward movement of ITCZ.
| Original language | English |
|---|---|
| Pages (from-to) | 234-239 |
| Number of pages | 6 |
| Journal | Journal of Asian Earth Sciences |
| Volume | 66 |
| DOIs | |
| Publication status | Published - 2013 Apr 8 |
Fingerprint
Keywords
- Holocene
- Kuroshio Current
- Mindanao Current
- North Equatorial Current
- Northwestern Pacific
- Sea surface temperature
- Seawater δO
ASJC Scopus subject areas
- Geology
- Earth-Surface Processes
Cite this
Persistent sea surface temperature and declined sea surface salinity in the northwestern tropical Pacific over the past 7500years. / Lo, Li; Lai, Yung Hsiang; Wei, Kuo Yen; Lin, Yu Shih; Mii, Horng-Sheng; Shen, Chuan Chou.
In: Journal of Asian Earth Sciences, Vol. 66, 08.04.2013, p. 234-239.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Persistent sea surface temperature and declined sea surface salinity in the northwestern tropical Pacific over the past 7500years
AU - Lo, Li
AU - Lai, Yung Hsiang
AU - Wei, Kuo Yen
AU - Lin, Yu Shih
AU - Mii, Horng-Sheng
AU - Shen, Chuan Chou
PY - 2013/4/8
Y1 - 2013/4/8
N2 - To understand Holocene climate evolutions in low-latitude region of the western Pacific, paired δ18O and Mg/Ca records of planktonic foraminifer Globigerinoides ruber (250-300μm, sensu stricto, s.s.) from a marine core ORI715-21 (121.5°E, 22.7°N, water depth 760m) underneath the Kuroshio Current (KC) off eastern Taiwan were analyzed. Over the past 7500years, the geochemical proxy-inferred sea surface temperature (SST) hovered around 27-28°C and seawater δ18O (δ18OW) slowly decreased 0.2-0.4‰ for two KC sites at 22.7° and 25.3°N. Comparison with a published high-SST and high-salinity equatorial tropical Pacific record, MD98-2181 located at the Mindanao Current (MC) at 6.3°N, reveals an anomalous time interval at 3.5-1.5kyr ago (before 1950 AD). SST gradient between the MC site and two KC site decrease from 1.5-2.0°C to only 0-1°C, and δ18OW from 0.1-0.3‰ to 0‰ for this 2-kyr time window. The high SST and low gradient could result from a northward shift of the North Equatorial Current, which implies a weakened KC. The long-term descending δ18OW and increasing precipitation in the entire low-latitude western Pacific and the gradually decreasing East Asian summer monsoonal rainfall during middle-to-late Holocene is likely caused by different land and ocean responses to solar insolation and/or enhanced moisture transportation from the Atlantic to Pacific associated with the southward movement of ITCZ.
AB - To understand Holocene climate evolutions in low-latitude region of the western Pacific, paired δ18O and Mg/Ca records of planktonic foraminifer Globigerinoides ruber (250-300μm, sensu stricto, s.s.) from a marine core ORI715-21 (121.5°E, 22.7°N, water depth 760m) underneath the Kuroshio Current (KC) off eastern Taiwan were analyzed. Over the past 7500years, the geochemical proxy-inferred sea surface temperature (SST) hovered around 27-28°C and seawater δ18O (δ18OW) slowly decreased 0.2-0.4‰ for two KC sites at 22.7° and 25.3°N. Comparison with a published high-SST and high-salinity equatorial tropical Pacific record, MD98-2181 located at the Mindanao Current (MC) at 6.3°N, reveals an anomalous time interval at 3.5-1.5kyr ago (before 1950 AD). SST gradient between the MC site and two KC site decrease from 1.5-2.0°C to only 0-1°C, and δ18OW from 0.1-0.3‰ to 0‰ for this 2-kyr time window. The high SST and low gradient could result from a northward shift of the North Equatorial Current, which implies a weakened KC. The long-term descending δ18OW and increasing precipitation in the entire low-latitude western Pacific and the gradually decreasing East Asian summer monsoonal rainfall during middle-to-late Holocene is likely caused by different land and ocean responses to solar insolation and/or enhanced moisture transportation from the Atlantic to Pacific associated with the southward movement of ITCZ.
KW - Holocene
KW - Kuroshio Current
KW - Mindanao Current
KW - North Equatorial Current
KW - Northwestern Pacific
KW - Sea surface temperature
KW - Seawater δO
UR - http://www.scopus.com/inward/record.url?scp=84875364824&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84875364824&partnerID=8YFLogxK
U2 - 10.1016/j.jseaes.2013.01.014
DO - 10.1016/j.jseaes.2013.01.014
M3 - Article
AN - SCOPUS:84875364824
VL - 66
SP - 234
EP - 239
JO - Journal of Asian Earth Sciences
JF - Journal of Asian Earth Sciences
SN - 1367-9120
ER -