@article {pienkowski_revised_2022,
	title = {Revised marine reservoir offset (ΔR) values for molluscs and marine mammals from Arctic North America},
	journal = {Boreas},
	year = {2022},
	note = {_eprint: https://onlinelibrary.wiley.com/doi/pdf/10.1111/bor.12606},
	month = {11/2022},
	abstract = {Appropriate marine{\textendash}terrestrial reservoir offset (ΔR) values are essential for accurate calibration of marine radiocarbon dates. However, ΔR values are only valid for the specific calibration curve that their calculation is based on. Here, we present revised ΔR values for the Marine20 calibration curve from Arctic North America, based on previously published 14C dates on pre-bomb live-collected marine molluscs (n = 124) and cetaceans (beluga whales; tooth dentine; n = 12), and bowhead whale{\textendash}driftwood age comparisons from the same glacio-isostatically uplifted shorelines (n = 18). Molluscan-based ΔR are: Chukchi/Beaufort sea coasts, 265{\textpm}116 14C years; NW Canadian Arctic Archipelago, 188{\textpm}91 14C years; NE Baffin Island, 81{\textpm}18 14C years; SE Baffin Island, 14{\textpm}58 14C years; Hudson Strait, -73{\textpm}64 14C years; Ungava Bay, 0{\textpm}86 14C years; Foxe Basin, 175{\textpm}89 14C years; Hudson Bay, -21{\textpm}72 14C years; James Bay, 209{\textpm}114 14C years; West Greenland, -93{\textpm}111 14C years. Species-specific marine mammal ΔR terms are 107{\textpm}59 14C years for beluga and 24{\textpm}58 14C years for bowheads. Our revised ΔR values are applicable for as long as the same broad oceanographic conditions (circulation, ventilation) have persisted, i.e. through the Holocene. While molluscan values are applicable to other marine carbonate (e.g. foraminifera), cetacean ΔR are valid only for the species they were calculated for and should not be applied to other marine mammals. Importantly, the ΔR terms calculated here are only valid for Marine20 and should not be used with earlier or later calibration curves.},
	doi = {https://doi.org/10.1111/bor.12606},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/bor.12606},
	author = {Pie{\'n}kowski, Anna J. and Coulthard, Roy D. and Furze, Mark F. A.}
}
@article {41,
	title = {The late Quaternary environmental evolution of marine Arctic Canada: Barrow Strait to Lancaster Sound},
	journal = {Quaternary Science Reviews},
	volume = {91},
	year = {2014},
	pages = {184-203},
	abstract = {A marine sediment core from the east-central Canadian Arctic Archipelago (Core 86027-154; 74{\textdegree} 22.01'N 89{\textdegree} 51.26'W; 329 m water depth), studied by a multiproxy approach [lithostratigraphy, biogeochemistry, micropalaeontology (dinoflagellate cysts, other non-pollen palynomorphs, benthic and planktonic foraminifera, ostracods)], and encompassing 14 AMS 14C dates, provides valuable insights into regional deglacial to Holocene palaeoenvironments. Six palaeoenvironmental zones are recognized, based on prominent changes in the litho- and biostratigraphy. The waterlain diamicton of Zone I records immediate deglaciation, being derived from lift-off and calving of previously grounded glacial ice. Though deglacial timing is complicated by the sparsity of dating materials and the Portlandia Effect, age{\textendash}depth model extrapolation places deglaciation at 11.54 cal ka BP. Zone II (11.5{\textendash}11.0 cal ka BP) represents a distinct progression from initially ice-proximal to increasingly ice-distal conditions, interrupted by an interval of pervasive sea-ice (11.4{\textendash}11.2 cal ka BP). Noteworthy biological activity commences in Zone III (11.0{\textendash}9.7 cal ka BP) with a prominent signal of planktonic foraminifera (Neogloboquadrina pachyderma). This likely signifies penetration of deeper, Atlantic-derived water through the central Canadian Arctic Archipelago upon deglaciation, facilitated by the greater, glacioisostatically-induced water depths (+80 m), and implies separation of Laurentide and Innuitian ice sheets by \~{}11.0 cal ka BP. Zone IV (9.7{\textendash}7.2 cal ka BP) records ameliorated, biologically favourable conditions with reduced seasonal sea-ice accompanied by high microfossil species diversity and the presence of subpolar taxa. Zone V (7.2{\textendash}6.5 cal ka BP) signals the exclusion of Atlantic-derived water, concomitant with increasing sea-ice, simultaneously representing the termination of the dynamic deglacial to early Holocene environments (zones I{\textendash}IV). Conditions similar to modern typified by uniform sediment characteristics, present-day microfossil assemblage structures, and sparse benthic foraminifera were established by 5.6 cal ka BP (Zone VI).},
	issn = {0277-3791},
	doi = {10.1016/j.quascirev.2013.09.025},
	url = {http://www.sciencedirect.com/science/article/pii/S0277379113003752},
	author = {Pie{\'n}kowski, Anna J. and England, John H. and Furze, Mark F. A. and MacLean, Brian and Blasco, Steve}
}
@article {64,
	title = {New cetacean ΔR values for Arctic North America and their implications for marine-mammal-based palaeoenvironmental reconstructions},
	journal = {Quaternary Science Reviews},
	volume = {91},
	year = {2014},
	pages = {218-241},
	abstract = {Radiocarbon-dated marine mammal remains from emergent Arctic coastlines have frequently been used to reconstruct Holocene sea-ice histories. The use of such reconstructions has hitherto been complicated by uncertain marine reservoir corrections precluding meaningful intercomparisons with data reported in calibrated or sidereal years. Based on an exhaustive compilation of previously published marine mammal radiocarbon dates (both live-harvested materials and subfossils) from the Canadian Arctic Archipelago (CAA), new, statistically-derived δ13C and ΔR values are provided. Average δ13C values are: -16.1 {\textpm} 1.1{\textperthousand} (bone collagen; n = 193) for bowhead (Balaena mysticetus); -14.4 {\textpm} 0.5{\textperthousand} (n = 44; dentine) for beluga (Delphinapterus leucas); -14.8 {\textpm} 1.9{\textperthousand} (teeth and tusks; n = 18) and -18.0 {\textpm} 4.7{\textperthousand} (n = 9; bone collagen) for walrus (Odobenus rosmarus). ΔR values are 170 {\textpm} 95 14C years for bowhead (n = 23) and 240 {\textpm} 60 14C years for beluga (n = 12). Scarce data preclude calculation of meaningful, statistically robust walrus ΔR. Using the new ΔR values, an expanded and revised database of calibrated bowhead dates (651 dates; many used in previous CAA sea-ice reconstructions) shows pronounced late Quaternary spatio-temporal fluctuations in bone abundance. Though broadly resembling earlier bowhead subfossil frequency data, analysis of the new expanded database suggests early- and mid-Holocene increases in whale abundance to be of longer duration and lower amplitude than previously considered. A more even and persistent spread of infrequent low-abundance remains during {\textquotedblleft}whale free{\textquotedblright} intervals is also seen. The dominance of three eastern regions (Prince Regent Inlet \& Gulf of Boothia; Admiralty Inlet; Berlinguet Inlet/Bernier Bay) in the CAA data, collectively contributing up to 88\% of all subfossil remains in the mid-Holocene, is notable. An analysis of calibrated regional sea-level index points suggests that severance of the Admiralty Inlet-Gulf of Boothia marine channel due to isostatically-driven regression may have played a significant role in enhanced whale mortality during this interval. Comparisons between the newly calibrated bowhead data and other regional sea-ice proxy data further highlight spatial and temporal discrepancies, potentially due to regional asynchronicities and variable sensitivities in proxy response to climate and oceanographic forcing. However, the limited number of deglacial{\textendash}postglacial marine records continues to hamper extensive intercomparisons between marine mammal and other proxy datasets. Nevertheless, an examination of assumptions inherent in linking bowhead subfossil frequencies, population densities, and sea-ice thickness and distribution, shows that such relationships are highly complex. Factors such as broad sea-ice preferences, variable mortality rates and causes, long distance carcass transport, variable coastline and basin/channel geometries, and changing emergence rates all complicate the correlation of whale bone abundance to sea-ice histories.},
	issn = {0277-3791},
	doi = {10.1016/j.quascirev.2013.08.021},
	url = {http://www.sciencedirect.com/science/article/pii/S027737911300334X},
	author = {Furze, Mark F. A. and Pie{\'n}kowski, Anna J. and Coulthard, Roy D.}
}
