Ice age terminations

Online Access: Get full text
doi: 10.1126/science.1177840
Author(s): Cheng, Hai; Edwards, R. Lawrence; Broecker, Wallace S.; Denton, George H.; Kong Xinggong; Wang Yongjin; Zhang, Rong; Wang, Xianfeng
Author Affiliation(s): Primary:
University of Minnesota, Department of Geology and Geophysics, Minneapolis, MN, United States
Lamont-Doherty Earth Observatory, United States
University of Maine, United States
Nanjing Normal University, China
NOAA, Geophysical Fluid Dynamics Laboratory, United States
Volume Title: Science
Source: Science, 326(5950), p.248-252. Publisher: American Association for the Advancement of Science, Washington, DC, United States. ISSN: 0036-8075 CODEN: SCIEAS
Note: In English. Supplemental information/data is available in the online version of this article. 63 refs.; illus.
Summary: 230Th-dated oxygen isotope records of stalagmites from Sanbao Cave, China, characterize Asian Monsoon (AM) precipitation through the ends of the third- and fourthmost recent ice ages. As a result, AM records for the past four glacial terminations can now be precisely correlated with those from ice cores and marine sediments, establishing the timing and sequence of major events. In all four cases, observations are consistent with a classic Northern Hemisphere summer insolation intensity trigger for an initial retreat of northern ice sheets. Meltwater and icebergs entering the North Atlantic alter oceanic and atmospheric circulation and associated fluxes of heat and carbon, causing increases in atmospheric CO2 and Antarctic temperatures that drive the termination in the Southern Hemisphere. Increasing CO2 and summer insolation drive recession of northern ice sheets, with probable positive feedbacks between sea level and CO2.
Year of Publication: 2009
Key Words: 24 Surficial Geology, Quaternary Geology; Actinides; Antarctica; Asia; Atlantic Ocean; Carbon dioxide; Cenozoic; China; Climate change; Correlation; Far East; Hubei China; Ice cores; Isotope ratios; Isotopes; Metals; North Atlantic; O-18/O-16; Oxygen; Paleoclimatology; Paleotemperature; Quaternary; Radioactive isotopes; Reconstruction; Sanbao Cave; Solution features; Speleothems; Stable isotopes; Stalagmites; Th-230; Thorium; Upper Quaternary
Coordinates: N314000 N314000 E1102600 E1102600
Record ID: 2010030531
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute.