@article {1977,
	title = {Radiocarbon dating of alkenones from marine sediments: I. Isolation protocol},
	journal = {Radiocarbon},
	volume = {47},
	year = {2005},
	note = {993nkTimes Cited:13
Cited References Count:22
},
	month = {2005},
	pages = {401-412},
	abstract = {The chemical and isotopic compositions of long-chain (C-36-C-39) unsaturated ketones (alkenones), a unique class of algal lipids, encode surface ocean properties useful for paleoceanographic reconstruction. Recently, we have sought to extend the utility of alkenones as oceanic tracers through measurement of their radiocarbon contents. Here. we describe a method for isolation of alkenones from sediments as a compound class based on a sequence of wet chemical techniques. The steps involved, which include silica gel column chromatography, urea adduction, and silver nitrate-silica gel column chromatography, exploit various structural attributes of the alkenones. Amounts of purified alkenones estimated by GC/FID measurements were highly correlated with CO2 yields after sample combustion, indicating purities of greater than 90\% for samples containing >= 100 mu g C. The degree of alkenone unsaturation (U-37(K{\textquoteright})) also varied minimally through the procedure. We also describe a high-performance liquid chromatography (HPLC) method to isolate individual alkenones for molecular-level structural and isotopic determination.},
	keywords = {AMS, carbon, indicators, proxy, records, tool},
	isbn = {0033-8222},
	author = {Ohkouchi, N. and Xu, L. and Reddy, C. M. and Montlucon, D. and Eglinton, T. I.}
}
@article {1980,
	title = {Radiocarbon dating of alkenones from marine sediments: II. Assessment of carbon process blanks},
	journal = {Radiocarbon},
	volume = {47},
	year = {2005},
	note = {993nkTimes Cited:13
Cited References Count:20
},
	month = {2005},
	pages = {413-424},
	abstract = {We evaluate potential process blanks associated with radiocarbon measurement of microgram to milligram quantities of alkenones at the National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) facility. Two strategies to constrain the contribution of blanks to alkenone C-14 dates were followed: 1) dating of samples of known age and 2) multiple measurements of identical samples. We show that the potential contamination associated with the procedure does not lead to a systematic bias of the results of alkenone dating to either younger or older ages. Our results indicate that alkenones record Delta(14)C of ambient DIC with an accuracy of approximately 10 parts per thousand. A conservative estimate of measurement precision is 17 parts per thousand for modern samples. Alkenone C-14 ages are expected to be reliable within 500 yr for samples younger than 10,500 C-14 yr.},
	keywords = {c-14 ams, organic-compounds, records, samples, system, tool},
	isbn = {0033-8222},
	author = {Mollenhauer, G. and Montlucon, D. and Eglinton, T. I.}
}
@article {2084,
	title = {East Asian monsoon forcing of suborbital variability in the Sulu Sea during Marine Isotope Stage 3: Link to Northern Hemisphere climate},
	journal = {Geochemistry Geophysics Geosystems},
	volume = {4},
	year = {2003},
	note = {631mwTimes Cited:41
Cited References Count:53
},
	month = {Jan 2},
	abstract = {[1] We have generated a new high-resolution record of variations in planktonic foraminiferal oxygen isotopes (delta(18)O) and Mg/Ca from a sediment core (IMAGES 97-2141) in the Sulu Sea located in the Philippine archipelago of western tropical Pacific. This record reveals distinct, suborbital-scale delta(18)O changes, most notably during Marine Isotope Stage 3 (MIS3) (similar to30,000 to 60,000 years B.P.). The amplitudes of these delta(18)O fluctuations (0.4 to 0.7parts per thousand) exceed that which can be attributed to sea level changes and must be due to changes in sea surface conditions. In the same interval, variations in planktonic foraminifera Mg/Ca suggest that suborbital surface ocean temperature variations of 1 to 1.5degreesC in the Sulu Sea were not in phase with delta(18)O. Combined, this evidence indicates that the MIS3 millennial delta(18)O events in the Sulu Sea were primarily the result of changes in surface water salinity, which today is directly related to the East Asian Monsoon (EAM) and its influence on the balance between surface water contributions from the South China Sea and Western Pacific Warm Pool (WPWP). Within dating uncertainties the MIS3 Sulu Sea delta(18)O suborbital variability indicates that times of fresher surface conditions in the Sulu Sea coincide with similar conditions in the WPWP [Stott et al., 2002] and also with intensifications of the summer EAM as recorded in the U-Th dated Chinese (Hulu Cave) speleothem delta(18)O record [Wang et al., 2001] and thus by inference with interstadials in the Greenland Ice core records. Combined, these results indicate that pronounced suborbital variability in the summer EAM and Intertropical Convergence Zone (ITCZ) during MIS3 was tightly coupled with climate conditions in the northern high latitudes.},
	keywords = {1620 global change : climate dynamics (3309), 4267 oceanography : general : paleoceanography, dissolution, equatorial pacific, eurasian snow cover, isotope stage 3, last glacial period, late pleistocene, Mg/Ca, millennial-scale climate change, oxygen isotopes, paleoceanography, planktonic-foraminifera, records, se asian monsoon, south china sea, summer monsoon, surface temperature-variations},
	isbn = {1525-2027},
	doi = {10.1029/2002GC000390},
	author = {Dannenmann, S. and Linsley, B. K. and Oppo, D. W. and Rosenthal, Y. and Beaufort, L.}
}
