@article {27,
	title = {Radiocarbon evidence for a possible abyssal front near 3.1 km in the glacial equatorial Pacific Ocean},
	journal = {Earth and Planetary Science Letters},
	volume = {425},
	year = {2015},
	pages = {93-104},
	abstract = {We investigate the radiocarbon ventilation age in deep equatorial Pacific sediment cores using the difference in conventional 14C age between coexisting benthic and planktonic foraminifera, and integrate those results with similar data from around the North Pacific Ocean in a reconstruction for the last glaciation (15 to 25 conventional 14C ka). Most new data from both the Equatorial Pacific and the Emperor Seamounts in the northwestern Pacific come from maxima in abundance of benthic taxa because this strategy reduces the effect of bioturbation. Although there remains considerable scatter in the ventilation age estimates, on average, ventilation ages in the Equatorial Pacific were significantly greater below 3.2 km ( \~{} 3080 {\textpm} 1125 yrs , n = 15 ) than in the depth interval 1.9 to 3.0 km ( \~{} 1610 {\textpm} 250 yrs , n = 12 ). When compared to the average modern seawater Δ C 14 profile for the North Pacific, the Equatorial Pacific glacial data suggest an abyssal front located somewhere between 3.0 and 3.2 km modern water depth. Above that depth, the data may indicate slightly better ventilation than today, and below that depth, glacial Equatorial Pacific data appear to be as old as last glacial maximum (LGM) deep water ages reported for the deep southern Atlantic. This suggests that a glacial reservoir of aged waters extended throughout the circumpolar Southern Ocean and into the Equatorial Pacific. Renewed ventilation of such a large volume of aged (and, by corollary, carbon-rich) water would help to account for the rise in atmospheric pCO2 and the fall in Δ C 14 as the glaciation drew to a close.},
	issn = {0012-821X},
	doi = {10.1016/j.epsl.2015.05.025},
	url = {http://www.sciencedirect.com/science/article/pii/S0012821X15003210},
	author = {Keigwin, L. D. and Lehman, S. J.}
}
@article {678,
	title = {Rapid sea-level rise and Holocene climate in the Chukchi Sea},
	journal = {Geology},
	volume = {34},
	year = {2006},
	note = {089zkTimes Cited:67Cited References Count:18},
	month = {Oct},
	pages = {861-864},
	abstract = {Three new sediment cores from the Chukchi Sea preserve a record of local paleoenvironment, sedimentation, and flooding of the Chukchi Shelf (similar to-50 m) by glacial-eustatic sea-level rise. Radiocarbon dates on foraminifera provide the first marine evidence that the sea invaded Hope Valley (southern Chukchi Sea, -53 m) as early as 12 ka. The lack of significant sediment accumulation since ca. 7 ka in Hope Valley, southeastern Chukchi Shelf, is consistent with decreased sediment supply and fluvial discharge to the shelf as deglaciation of Alaska concluded. Abundant benthic foraminifera from a site west of Barrow Canyon indicate that surface waters were more productive 4-6 ka, and this productivity varied on centennial time scales. An offshore companion to this core contains a 20 m record of the Holocene. These results show that carefully selected core sites from the western Arctic Ocean can have a temporal resolution equal to the best cores from other regions, and that these sites can be exploited for high-resolution studies of the paleoenvironment.},
	issn = {0091-7613},
	doi = {10.1130/G22712.1},
	author = {Keigwin, L. D. and Donnelly, J. P. and Cook, M. S. and Driscoll, N. W. and Brigham-Grette, J.}
}
@article {694,
	title = {Radiocarbon variability in the western North Atlantic during the last deglaciation},
	journal = {Science},
	volume = {310},
	year = {2005},
	note = {Robinson, Laura FAdkins, Jess FKeigwin, Lloyd DSouthon, JohnFernandez, Diego PWang, S-LScheirer, Daniel SengResearch Support, Non-U.S. Gov{\textquoteright}tResearch Support, U.S. Gov{\textquoteright}t, Non-P.H.S.2005/12/03 09:00Science. 2005 Dec 2;310(5753):1469-73. Epub 2005 Nov 3.},
	month = {Dec 02},
	pages = {1469-73},
	abstract = {We present a detailed history of glacial to Holocene radiocarbon in the deep western North Atlantic from deep-sea corals and paired benthic-planktonic foraminifera. The deglaciation is marked by switches between radiocarbon-enriched and -depleted waters, leading to large radiocarbon gradients in the water column. These changes played an important role in modulating atmospheric radiocarbon. The deep-ocean record supports the notion of a bipolar seesaw with increased Northern-source deep-water formation linked to Northern Hemisphere warming and the reverse. In contrast, the more frequent radiocarbon variations in the intermediate/deep ocean are associated with roughly synchronous changes at the poles.},
	issn = {0036-8075 (Linking)},
	doi = {10.1126/science.1114832},
	author = {Robinson, L. F. and Adkins, J. F. and Keigwin, L. D. and Southon, J. and Fernandez, D. P. and Wang, S. L. and Scheirer, D. S.}
}
@article {2044,
	title = {Radiocarbon and stable isotope constraints on Last Glacial Maximum and Younger Dryas ventilation in the western North Atlantic},
	journal = {Paleoceanography},
	volume = {19},
	year = {2004},
	note = {870dfTimes Cited:72
Cited References Count:60
},
	month = {Nov 3},
	abstract = {[1] Foraminiferal abundance, C-14 ventilation ages, and stable isotope ratios in cores from high deposition rate locations in the western subtropical North Atlantic are used to infer changes in ocean and climate during the Younger Dryas (YD) and Last Glacial Maximum (LGM). The delta(18)O of the surface dwelling planktonic foram Globigerinoides ruber records the present-day decrease in surface temperature (SST) of similar to 4 degreesC from Gulf Stream waters to the northeastern Bermuda Rise. If during the LGM the modern delta(18)O/salinity relationship was maintained, this SST contrast was reduced to 2 degreesC. With LGM to interglacial delta(18)O changes of at least 2.2parts per thousand, SSTs in the western subtropical gyre may have been as much as 5 degreesC colder. Above similar to 2.3 km, glacial delta(13)C was higher than today, consistent with nutrient-depleted ( younger) bottom waters, as identified previously. Below that, delta(13)C decreased continually to - 0.5parts per thousand, about equal to the lowest LGM delta(13)C in the North Pacific Ocean. Seven pairs of benthic and planktonic foraminiferal C-14 dates from cores > 2.5 km deep differ by 1100 +/- 340 years, with a maximum apparent ventilation age of similar to 1500 years at 4250 m and at similar to 4700 m. Apparent ventilation ages are presently unavailable for the LGM < 2.5 km because of problems with reworking on the continental slope when sea level was low. Because LGM \&delta;C-13 is about the same in the deep North Atlantic and the deep North Pacific, and because the oldest apparent ventilation ages in the LGM North Atlantic are the same as the North Pacific today, it is possible that the same water mass, probably of southern origin, flowed deep within each basin during the LGM. Very early in the YD, dated here at 11.25 +/- 0.25 ( n = 10) conventional C-14 kyr BP ( equal to 12.9 calendar kyr BP), apparent ventilation ages < 2.3 km water depth were about the same as North Atlantic Deep Water today. Below similar to 2.3 km, four YD pairs average 1030 +/- 400 years. The oldest apparent ventilation age for the YD is 1600 years at 4250 m. This strong contrast in ventilation, which indicates a front between water masses of very different origin, is similar to glacial profiles of nutrient-like proxies. This suggests that the LGM and YD modes of ocean circulation were the same.},
	keywords = {benthic foraminifera, deep-sea sediments, ice-age, Ocean circulation, ocean ventilation, pacific-ocean, radiocarbon, SARGASSO SEA, southern-ocean, Thermohaline circulation, united-states, water circulation, western north atlantic},
	isbn = {0883-8305},
	doi = {10.1029/2004PA001029},
	url = {http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2\&amp;SrcAuth=Alerting\&amp;SrcApp=Alerting\&amp;DestApp=WOS\&amp;DestLinkType=FullRecord;UT=WOS:000225033500003},
	author = {Keigwin, L. D.}
}
@article {755,
	title = {The Role of the Deep-Ocean in North-Atlantic Climate-Change between 70-Kyr and 130-Kyr Ago},
	journal = {Nature},
	volume = {371},
	year = {1994},
	note = {Ph254Times Cited:159Cited References Count:32},
	month = {Sep 22},
	pages = {323-326},
	abstract = {THE suggestion(1) that changes in North Atlantic Deep Water (NADW) production are linked through surface heat flux to the atmospheric temperature over Greenland is supported by earlier indications(2,3) that NADW production decreased during glacial times, and by the subsequent finding(4-6) that it declined during the Younger Dryas cool period at the end of the last glaciation. Changes in North Atlantic surface temperatures have been found? to mirror high-frequency temperature changes recorded in Greenland ice cores over the past 80 kyr, but the connection to abyssal circulation has yet to be established, except for one or two isolated oscillations(8,9). Here we present carbon and oxygen isotope analyses of benthic foraminifera in a high-resolution North Atlantic deepsea sediment core for the period 70-130 kyr ago. These data allow us to reconstruct the history of NADW production, which shows a close correlation with Greenland climate variability for much of this time interval, suggesting that the climate influence of NADW variability was widespread. We see no evidence, however, for changes in NADW production during substage 5e (the Eemian interglacial period), in contrast with recent ice-core data(10) which suggest severe climate instability in Greenland during this time period. Our results may support suggestions, based on data from a second ice core, that this apparent instability is am artefact caused by ice flow(11). Alternatively, the Eemian climate instability may have had a different origin from the subsequent climate events.},
	issn = {0028-0836},
	doi = {10.1038/371323a0},
	author = {Keigwin, L. D. and Curry, W. B. and Lehman, S. J. and Johnsen, S.}
}
