@article {zhou_authigenic_2023,
	title = {Authigenic uranium deposition in the glacial North Atlantic: Implications for changes in oxygenation, carbon storage, and deep water-mass geometry},
	journal = {Quaternary Science Reviews},
	volume = {300},
	year = {2023},
	month = {01/2023},
	pages = {107914},
	abstract = {Oxygen in the ocean has essential ecological and climatic functions, and can be an important indicator of deep-ocean ventilation and carbon storage. Previous studies are divided on whether the subsurface North Atlantic, which today is well-oxygenated, had higher or lower oxygen levels during the Last Glacial Maximum (LGM). Crucially, the limited number of previous reconstructions precludes any conclusions regarding basin-wide patterns in past changes in oxygenation. Authigenic uranium in deep-sea sediments is a sensitive redox tracer that can shed light on bottom water oxygen. Here, we leverage published and new U- and Th-series isotope measurements from North Atlantic sediments to calculate the mass accumulation rate of authigenic uranium (aU MAR) during the Holocene and the LGM. We find that greater aU burial, reflecting lower-than-Holocene oxygen levels and correspondingly greater respired carbon storage, were persistent features of the LGM in the deep North Atlantic. The eastern basin was substantially less well-oxygenated than the western basin. This zonal contrast is possibly related to the farther advance and greater infilling to the east of the mid-Atlantic Ridge of deep waters originating from the Southern Ocean. An alternative explanation is the different residence time in the two basins of deep waters originating from the subpolar North Atlantic. Previous compilations of two nutrient tracers, δ13C and CdW, are consistent with the varying-deep-circulation interpretation of our aU MAR dataset. The observed threshold behavior of aU or the pattern of export productivity, especially at high latitudes, may also have enhanced this west-east difference.},
	keywords = {Authigenic uranium, Bottom water oxygen, Last glacial maximum, North Atlantic},
	issn = {0277-3791},
	doi = {10.1016/j.quascirev.2022.107914},
	url = {https://www.sciencedirect.com/science/article/pii/S0277379122005455},
	author = {Zhou, Y. and McManus, J. F.}
}
@article {2677,
	title = {Coupled ocean and atmospheric changes during Greenland stadial 1 in southwestern Europe},
	journal = {Quaternary Science Reviews},
	volume = {212},
	year = {2019},
	month = {Jan-05-2019},
	pages = {108 - 120},
	abstract = {Paleoclimate reconstructions suggest that the complex variability within the Greenland stadial 1 (GS-1) over western Europe was governed by coupled ocean and atmospheric changes. However, few works from the North Atlantic mid-latitudes document both the GS-1 onset and its termination, which are often considered as single abrupt transition events. Here, we present a direct comparison between marine (alkenone-based sea surface temperatures) and terrestrial (pollen) data, at very high resolution (28 years mean), from the southwestern Iberian shelf record D13882. Our results reveal a rather complex climatic period with internally changing conditions. The GS-1 onset (GS-1a: 12890-12720 yr BP) is marked by a progressive cooling and drying; GS-1b (12720-12390 yr BP) is the coldest and driest phase; GS-1c (12390-12030 yr BP) is marked by a progressive warming and increase in moisture conditions; GS-1 termination (GS-1d: 12030-11770 yr BP) is marked by rapid switches between cool wet, cold dry and cool wet conditions. Although hydroclimate response was very unsteady throughout the GS-1 and in particular during its termination phase, the persistence of an open temperate and Mediterranean forest in southwestern Iberia during the entire episode suggests that at least some moisture was delivered via the Westerlies. We propose coupled ocean and atmospheric mechanisms to reproduce these scenaria. Changes in the strength of the Atlantic Meridional Overturning Circulation (AMOC) as well as variations in the North Atlantic sea-ice growth have favoured the displacement of the polar jet stream{\textquoteright}s latitudinal position and contributed to a complex spatial pattern and strength of the Westerlies across western Europe.},
	keywords = {Climate variability, Greenland stadial, Iberian margin, Jet stream, Moisture availability, North Atlantic, Paleoclimate, Westerlies, Younger Dryas Complex},
	issn = {02773791},
	doi = {10.1016/j.quascirev.2019.03.033},
	url = {https://www.researchgate.net/publication/332292599_Coupled_ocean_and_atmospheric_changes_during_Greenland_stadial_1_in_southwestern_Europe},
	author = {Naughton, F. and Costas, S. and Gomes, S.D. and Desprat, S. and Rodrigues, T. and Sanchez Go{\~n}i, M.F. and Renssen, H. and Trigo, R. and Bronk-Ramsey, C. and Oliveira, D. and Salgueiro, E. and Voelker, A.H.L. and Abrantes, F.}
}
@article {2691,
	title = {Holocene and Last Interglacial climate of the Faroe Islands from sedimentary plant wax hydrogen and carbon isotopes},
	journal = {Quaternary Science Reviews},
	volume = {223},
	year = {2019},
	month = {Jan-11-2019},
	pages = {105930},
	abstract = {The Last Interglacial period (LIG) is Earth{\textquoteright}s most recent globally warm period and is analogous in some ways to projected future global warming. However, questions remain regarding the state of the climate during the LIG in the North Atlantic, a region that is extremely sensitive to changes in oceanic and atmospheric circulation. Here, we present hydrogen and carbon isotope (δD and δ13C) records from a suite of plant wax biomarkers preserved in Holocene and LIG lacustrine sediments from the North Atlantic Faroe Islands and interpret them as qualitative proxies for temperature and hydroclimate variability. These data are used to directly compare LIG and Holocene climate using the same proxy approaches from the same terrestrial location. Measuring multiple isotopes on multiple types of waxes elucidates the sources of homologous plant waxes. We deduce that the δD values of long-chain n-alkanes (C27{\textendash}C33) and mid-chain n-alkanes (C23{\textendash}C25) in these sedimentary archives reflect leaf water and lake water δD values, respectively, while the δD values for both long-chain (C28{\textendash}C30) and mid-chain n-alkanoic acids (C24{\textendash}C26) primarily represent lake water δD values. Plant wax-inferred δD values of precipitation during the early Holocene (10,100 to 8,200  cal  yr BP) are \~{}35{\textperthousand} more positive than late Holocene values, and decline over the Holocene. δD-inferred hydrologic change and δ13C -inferred plant water use efficiency both indicate that the Faroe Islands became drier throughout the Holocene. Comparison with measurements from LIG plant waxes indicates that late LIG in the Faroe Islands was hydrologically similar to the early-to mid-Holocene (8,200 to 4,000  cal  yr BP), with enriched precipitation isotopes and reduced evapotranspiration indicating a warmer, wetter environment.},
	keywords = {Holocene, interglacial, North Atlantic, Organic geochemistry, paleoclimatology, Stable isotopes},
	issn = {02773791},
	doi = {10.1016/j.quascirev.2019.105930},
	url = {https://www.sciencedirect.com/science/article/pii/S0277379119304251},
	author = {Curtin, Lorelei and D{\textquoteright}Andrea, William J. and Balascio, Nicholas and Pugsley, Genevieve and de Wet, Gregory and Bradley, Raymond}
}
@inbook {1390,
	title = {North Atlantic intermediate depth variability during the Younger Dryas; evidence from benthic foraminiferal Mg/Ca and the GFDL R30 coupled climate model},
	booktitle = {Geophysical Monograph, vol. 173},
	year = {2007},
	note = {id: 857; American Geophysical Union 2005 fall meeting, San Francisco, CA, United States, Dec 5-9, 2005 NSF grants OCE-0096495, ATM-0502428, OCE-0096472, OCE-0220776 and ATM-0501351 References: 72; illus.; Y},
	month = {2007},
	pages = {247-263},
	publisher = {American Geophysical Union},
	organization = {American Geophysical Union},
	address = {Washington},
	keywords = {24, Quaternary geology, Atlantic Ocean, benthic environment, Cenozoic, chemical ratios, Foraminifera, Glaciation, Gulf of Mexico, ice cores, Invertebrata, isotope ratios, isotopes, Little Bahama Bank, Mg/Ca, microfossils, North Atlantic, O-18/O-16, oxygen, paleo-oceanography, paleobathymetry, paleosalinity, paleotemperature, Pleistocene, Protista, Quaternary, Stable isotopes, Straits of Florida, upper, upper Weichselian, Weichselian, Younger Dryas},
	isbn = {9780875904382},
	author = {Came, Rosemarie E. and Curry, William B. and Oppo, Delia W. and Broccoli, Anthony J. and Stouffer, Ronald J. and Lynch-Stieglitz, Jean},
	editor = {Schmittner, Andreas}
}
@article {1012,
	title = {Radiocarbon calibration beyond 20,000 B.P. by means of planktonic foraminifera of the Iberian Margin},
	journal = {Quaternary Research},
	volume = {61},
	year = {2004},
	note = {id: 401},
	pages = {204-214},
	abstract = {We present a new set of 14C ages obtained by accelerator mass spectrometry (AMS) on planktonic foraminifera from a deep-sea core collected off the Iberian Margin (MD952042). This site, at 37{\textdegree}N, is distant from the high-latitude zones where 14C reservoir age is large and variable. Many independent proxies {\textemdash} alkenones, magnetic susceptibility, ice-rafted debris, foraminifera stable isotopes, abundances of foraminifera, pollen, and dinoflagellates {\textemdash} show abrupt changes correlative with Dansgaard-Oeschger and Heinrich events of the last glacial period. The good stratigraphic agreement of all proxies {\textemdash} from the fine to the coarse-size fractions {\textemdash} indicates that the foraminifera 14C ages are representative of the different sediment fractions. To obtain reliable 14C ages of foraminifera beyond 20,000 14C yr B.P., we leached the shells prior to carbonate hydrolysis and subsequent analysis. For a calendar age scale, we matched the Iberian Margin U37K' profile with that of Greenland Summit δ18O. Both are proxies for temperature, which in models varies synchronously in the two areas. The match creates no spurious jumps in sedimentation rate and requires only a limited number of tie points. Except for ages older than 40,000 14C yr B.P., Greenland{\textquoteright}s GISP2 and GRIP records yield similar calendars. The 14C and imported calendar ages of the Iberian Margin record are then compared to data {\textemdash} from lacustrine annual varves and from corals and speleothems dated by U{\textendash}Th {\textemdash} previously used to extend the calibration beyond 20,000 14C yr B.P. The new record follows a smooth pattern between 23,000 and 50,000 cal yr B.P. We find good agreement with the previous data sets between 23,000 and 31,000 cal yr B.P. In the interval between 33,000 and 41,000 cal yr B.P., for which previous records disagree by up to 5000 cal yr, the Iberian Margin record closely follows the polynomial curve that was previously defined by an interpolation of the coral ages and runs between the Lake Suigetsu and the Bahamian speleothem data sets.},
	keywords = {Dansgaard-Oeschger events, Heinrich events, Laschamp magnetic excursion, Last glacial cycle, North Atlantic, Radiocarbon calibration},
	doi = {10.1016/j.yqres.2003.11.006},
	author = {Bard, E. and Rostek, F. and Menot-Combes, G.}
}
