Gulf of Alaska Alkenone paleotemperatures, d18Oseawater reconstructions, benthic oxygen isotopes and benthic faunal data for the past 18,000 years Praetorius, S.K.; Mix, A.C.; Davies-Walczak, M.H.; Wolhowe, M.D.; Addison, J.A.; Prahl, F.G. Praetorius, S.K. Mix, A.C. Davies-Walczak, M.H. Wolhowe, M.D. Addison, J.A. Prahl, F.G. Sea Surface Temperature Reconstruction earth science/paleoclimate/climate reconstructions|paleoceanography (depth at sample end,null,null,centimeter,null,climate reconstructions|paleoceanography,null,null,N,null) earth science/paleoclimate/climate reconstructions|paleoceanography (depth at sample start,null,null,centimeter,null,climate reconstructions|paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (alkenone unsaturation index Uk37 prime,null,one standard deviation,dimensionless,null,paleoceanography,null,gas chromatography,N,null) earth science/paleoclimate/paleoceanography (alkenone unsaturation index Uk37 prime,null,one standard deviation upper bound,dimensionless,null,paleoceanography,null,gas chromatography,N,null) earth science/paleoclimate/paleoceanography (weight,dry sediment,null,gram,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (identified foraminifer,null,null,count,null,paleoceanography,null,null,N,Nonionella) earth science/paleoclimate/paleoceanography (delta 18O,Cibicidoides wuellerstorfi,null,per mil VPDB,null,paleoceanography,corrected,null,N,corrected to Uvigerina peregrina d18O equivalent by adding 0.64; Sealevel corrected based on the reconstruction of Waelbroeck et al. 2002) earth science/paleoclimate/paleoceanography (sample identification,null,null,null,null,paleoceanography,null,null,C,core name) earth science/paleoclimate/climate reconstructions|paleoceanography (sea surface temperature,alkenone unsaturation index,one standard deviation upper bound,degree Celsius,null,climate reconstructions|paleoceanography,null,null,N,Calibration: Prahl et al. 1988) earth science/paleoclimate/climate reconstructions|paleoceanography (delta 18O,alkenone unsaturation index|delta 18O|sea water,one standard deviation lower bound,per mil PDB,null,climate reconstructions|paleoceanography,null,null,N,Calibration: Bemis et al. 1998; using G. bulloides) earth science/paleoclimate/climate reconstructions|paleoceanography (delta 18O,alkenone unsaturation index|delta 18O|sea water,one standard deviation upper bound,per mil PDB,null,climate reconstructions|paleoceanography,null,null,N,Calibration: Bemis et al. 1998; using G. bulloides) earth science/paleoclimate/climate reconstructions|paleoceanography (sea surface temperature,alkenone unsaturation index,one standard deviation lower bound,degree Celsius,null,climate reconstructions|paleoceanography,null,null,N,Calibration: Prahl et al. 1988) earth science/paleoclimate/climate reconstructions|paleoceanography (delta 18O,alkenone unsaturation index|delta 18O|sea water,null,per mil PDB,null,climate reconstructions|paleoceanography,corrected,null,N,Calibration: Bemis et al. 1998; sealevel correction based on Waelbroeck et al. 2002; using G. bulloides) earth science/paleoclimate/climate reconstructions|paleoceanography (delta 18O,alkenone unsaturation index|delta 18O|sea water,one standard deviation upper bound,per mil PDB,null,climate reconstructions|paleoceanography,null,null,N,Calibration: Bemis et al. 1998; using N. pachyderma s.) earth science/paleoclimate/paleoceanography (depth,null,null,meter,null,paleoceanography,null,null,N,midpoint depth in core) earth science/paleoclimate/paleoceanography (identified foraminifer,null,null,count,null,paleoceanography,null,null,N,Epistominella pacifica) earth science/paleoclimate/paleoceanography (total benthic foraminifers,null,null,count,null,paleoceanography,null,null,N,Total benthic fauna) earth science/paleoclimate/paleoceanography (delta 18O,Globigerina bulloides,null,per mil,null,paleoceanography,null,isotope ratio mass spectrometry,N,null) earth science/paleoclimate/paleoceanography (delta 18O,Neogloboquadrina pachyderma sinistral,null,per mil,null,paleoceanography,null,isotope ratio mass spectrometry,N,null) earth science/paleoclimate/paleoceanography (age,null,null,calendar year before present,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (identified foraminifer,null,null,count,null,paleoceanography,null,null,N,Islandiella) earth science/paleoclimate/climate reconstructions|paleoceanography (depth,null,null,meter,null,climate reconstructions|paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (C37 alkenone,null,null,milligram per gram,null,paleoceanography,null,null,N,concentration of C37 ketone abundance) earth science/paleoclimate/paleoceanography (identified foraminifer,null,null,count,null,paleoceanography,null,null,N,Bulimina exilis) earth science/paleoclimate/paleoceanography (identified foraminifer,null,null,count,null,paleoceanography,null,null,N,Bulimina striata) earth science/paleoclimate/paleoceanography (identified foraminifer,null,null,count,null,paleoceanography,null,null,N,Globobulimina affinis) earth science/paleoclimate/paleoceanography (identified foraminifer,null,null,count,null,paleoceanography,null,null,N,Elphidium batialis) earth science/paleoclimate/paleoceanography (identified foraminifer,null,null,count,null,paleoceanography,null,null,N,unidentified: cibicidoides-like) earth science/paleoclimate/climate reconstructions|paleoceanography (sample identification,null,null,null,null,climate reconstructions|paleoceanography,null,null,C,core name) earth science/paleoclimate/climate reconstructions|paleoceanography (delta 18O,alkenone unsaturation index|delta 18O|sea water,null,per mil PDB,null,climate reconstructions|paleoceanography,null,null,N,Calibration: Bemis et al. 1998; using G. bulloides) earth science/paleoclimate/paleoceanography (age,null,one standard deviation,calendar year before present,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (alkenone unsaturation index Uk37 prime,null,one standard deviation lower bound,dimensionless,null,paleoceanography,null,gas chromatography,N,null) earth science/paleoclimate/paleoceanography (depth at sample start,null,null,centimeter,null,paleoceanography,null,null,N,null) earth science/paleoclimate/climate reconstructions|paleoceanography (delta 18O,alkenone unsaturation index|delta 18O|sea water,one standard deviation lower bound,per mil PDB,null,climate reconstructions|paleoceanography,null,null,N,Calibration: Bemis et al. 1998; using N. pachyderma s.) earth science/paleoclimate/paleoceanography (delta 18O,Uvigerina peregrina,null,per mil VPDB,null,paleoceanography,null,isotope ratio mass spectrometry,N,null) earth science/paleoclimate/paleoceanography (delta 18O,Cibicidoides wuellerstorfi,null,per mil VPDB,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (delta 18O,Cibicidoides wuellerstorfi,null,per mil VPDB,null,paleoceanography,corrected,null,N,corrected to Uvigerina peregrina d18O equivalent by adding 0.64) earth science/paleoclimate/climate reconstructions|paleoceanography (depth,null,null,meter,null,climate reconstructions|paleoceanography,null,null,N,midpoint depth in core) earth science/paleoclimate/climate reconstructions|paleoceanography (age,null,null,calendar year before present,null,climate reconstructions|paleoceanography,null,null,N,null) earth science/paleoclimate/climate reconstructions|paleoceanography (sea surface temperature,alkenone unsaturation index,null,degree Celsius,null,climate reconstructions|paleoceanography,null,null,N,Calibration: Prahl et al. 1988) earth science/paleoclimate/climate reconstructions|paleoceanography (delta 18O,alkenone unsaturation index|delta 18O|sea water,null,per mil PDB,null,climate reconstructions|paleoceanography,null,null,N,Calibration: Bemis et al. 1998; using N. pachyderma s.) earth science/paleoclimate/climate reconstructions|paleoceanography (delta 18O,alkenone unsaturation index|delta 18O|sea water,null,per mil PDB,null,climate reconstructions|paleoceanography,null,null,N,Calibration: Bemis et al. 1998; sealevel correction based on Waelbroeck et al. 2002; using N. pachyderma s.) earth science/paleoclimate/paleoceanography (delta 18O,Uvigerina peregrina,null,per mil VPDB,null,paleoceanography,corrected,isotope ratio mass spectrometry,N,Sealevel corrected based on the reconstruction of Waelbroeck et al. 2002) earth science/paleoclimate/paleoceanography (depth at sample end,null,null,centimeter,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (grain size class,sediment,null,fraction,null,paleoceanography,null,null,N,Coarse fraction >125 um) earth science/paleoclimate/paleoceanography (Uvigerina peregrina,null,null,count,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (identified foraminifer,null,null,count,null,paleoceanography,null,null,N,Bolivina) earth science/paleoclimate/paleoceanography (identified foraminifer,null,null,count,null,paleoceanography,null,null,N,Spiroloculina) earth science/paleoclimate/paleoceanography (identified foraminifer,null,null,count,null,paleoceanography,null,null,N,Oolina) earth science/paleoclimate/paleoceanography (identified foraminifer,null,null,count,null,paleoceanography,null,null,N,Pyrgo) earth science/paleoclimate/paleocean earth science/paleoclimate/paleocean earth science/paleoclimate/paleocean earth science/paleoclimate/paleocean earth science/paleoclimate/paleocean (EW0408-85JC>LATITUDE 59.555>LONGITUDE -144.1535) (EW0408-26TC/JC>LATITUDE 56.96>LONGITUDE -136.43) (EW0408-87JC>LATITUDE 58.77>LONGITUDE -144.5) Marine sediments from the North Pacific document two episodes of expansion and strengthening of the subsurface oxygen minimum zone (OMZ) accompanied by seafloor hypoxia during the last deglacial transition. The mechanisms driving this hypoxia remain under debate. We present a new high-resolution alkenone palaeotemperature reconstruction from the Gulf of Alaska that reveals two abrupt warming events of 4–5 degrees Celsius at the onset of the Bølling and Holocene intervals that coincide with sudden shifts to hypoxia at intermediate depths. The presence of diatomaceous laminations and hypoxia-tolerant benthic foraminiferal species, peaks in redox-sensitive trace metals, and enhanced 15N/14N ratio of organic matter, collectively suggest association with high export production. A decrease in 18O/16O values of benthic foraminifera accompanying the most severe deoxygenation event indicates subsurface warming of up to about 2 degrees Celsius. We infer that abrupt warming triggered expansion of the North Pacific OMZ through reduced oxygen solubility and increased marine productivity via physiological effects; following initiation of hypoxia, remobilization of iron from hypoxic sediments could have provided a positive feedback on ocean deoxygenation through increased nutrient utilization and carbon export. Such a biogeochemical amplification process implies high sensitivity of OMZ expansion to warming. STUDY NOTES: Alkenone paleotemperatures, d18Oseawater reconstructions, and benthic faunal data in this worksheet are from jumbo piston core EW0408-85JC in the Gulf of Alaska. The age model for this core is previously published in Davies-Walczak et al., 2014 (DOI: 10.1016/j.epsl.2014.04.004). Additional benthic oxygen isotope data is provided from cores EW0408-87JC and EW0408-26JC in the Gulf of Alaska, along with the radiocarbon chronology for EW0408-87JC. Source reference for EW0408-26JC age model- Praetorius, S.K. and A.C., Science, 2014 (DOI: 10.1126/science.1252000). Please cite original reference when using this data and consult original publication for details on radiocarbon chronology. Sediment concentrations (K37's mg/g) are not reported for a small number of samples for which analysis of the recovery standard was compromised (indicated with NAN). Provided Keywords: ocean hypoxia, deglacial, oxygen minimum zone, alkenone paleotemperature NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Praetorius, S.K. Investigator : Mix, A.C. Investigator : Davies-Walczak, M.H. Investigator : Wolhowe, M.D. Investigator : Addison, J.A. Investigator : Prahl, F.G. 2017-04-18 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/21950 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-nps-d18o-85jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-faunal-85jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-gbull-d18o-85jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-age-85jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-87jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-26jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-alkenone-85jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-nps-d18o-85jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-faunal-85jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-gbull-d18o-85jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-age-85jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-87jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-26jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-alkenone-85jc.txt English https://www.ncdc.noaa.gov/paleo/study/21950 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-nps-d18o-85jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-faunal-85jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-gbull-d18o-85jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-age-85jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-87jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-26jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/praetorius2015/praetorius2015-alkenone-85jc.txt Praetorius, S.K., A.C. Mix, M.H. Davies, M.D. Wolhowe, J.A. Addison, and F.G. Prahl2015North Pacific deglacial hypoxic events linked to abrupt ocean warmingNature527362-36610.1038/nature15753http://www.nature.com/nature/journal/v527/n7578/full/nature15753.html Davies, M.H., A.C. Mix, J.S. Stoner, J.A. Addison, J. Jaeger, B. Finney, and J. Wiest2011The deglacial transition on the southeastern Alaska Margin: Meltwater input, sea level rise, marine productivity, and sedimentary anoxiaPaleoceanography26PA222310.1029/2010PA002051 START YEAR: 18120 cal yr BP * END YEAR: 500 cal yr BP -144.5 56.96 -136.43 59.555