@inbook{d1247ced4bbc4a41b0e53385ed35cecc,
title = "Ice-core evidence of late-holocene reduction in north Atlantic ocean heat transport",
abstract = "The several-millennial cooling in central Greenland since the middle Holocene probably was caused by a trend to reduced oceanic heat transport as well as by orbital forcing, based on several lines of evidence. The late-Holocene trend is similar in many ways to the older coolings associated with abrupt, millennial climate changes. Climate records from Greenland ice cores indicate that both abrupt and gradual coolings involved: (i) greater temperature decrease in winter than in summer; (ii) greater accumulation-rate decrease in winter than in summer causing normally calibrated ice-isotopic changes to underestimate temperature changes; and (iii) increasing interannual climate variability. Paleoclimatic data and model results show that abrupt coolings have been linked to reduction in North Atlantic oceanic heat transport; we suggest that decreasing North Atlantic oceanic heat transport has also contributed to the Holocene trend. Gradual reductions in ocean heat transport precede abrupt reductions in both paleoclimatic records and model results, so it is likely that the natural trend has been toward the threshold for abrupt change in the late Holocene.",
author = "Alley, {Richard B.} and {\'A}g{\'u}stsd{\'o}ttir, {Anna Mari} and Fawcett, {Peter J.}",
note = "Funding Information: Acknowledgements.W e thank the GISP2 ScienceM anage- ment Office, the 109th New York Air National Guard, the Polar Ice Coring Office, the National Ice Core Laboratory, the Na- tional Science Foundation Office of Polar Programs, two anonymous reviewers, and numerousc olleagues at GISP2, GRIP, and elsewhere. We thank Peter Clark and Robin Webb for organizingt he meeting. RBA also thanks the D.&L. Pack- ard Foundationf or partial funding. Funding Information: We thank the GISP2 Science Management Office, the 109th New York Air National Guard, the Polar Ice Coring Office, the National Ice Core Laboratory, the National Science Foundation Office of Polar Programs, two anonymous reviewers, and numerous colleagues at GISP2, GRIP, and elsewhere. We thank Peter Clark and Robin Webb for organizing the meeting. RBA also thanks the D.&L. Packard Foundation for partial funding. Publisher Copyright: {\textcopyright} 1999 by the American Geophysical Union.",
year = "1999",
doi = "10.1029/GM112p0301",
language = "English (US)",
isbn = "9780875900957",
series = "Geophysical Monograph Series",
publisher = "Blackwell Publishing Ltd",
pages = "301--312",
editor = "Keigwin, {Lloyd D.} and Clark, {Peter U.} and Webb, {Robert S.}",
booktitle = "Mechanisms of Global Climate Change at Millennial Time Scales, 1999",
}