Benguela Current GeoB 1023-5 21ka Alkenone SST Reconstruction Kim, J.-H.; Schneider, R.R.; Mueller, P.J.; Wefer, G. Kim, J.-H. Schneider, R.R. Mueller, P.J. Wefer, G. Sea Surface Temperature Reconstruction earth science/paleoclimate/paleoceanography (age,null,null,calendar year before present,null,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,null) earth science/paleoclimate/paleoceanography (alkenone unsaturation index Uk37 prime,null,null,dimensionless,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (sedimentation rate,null,null,centimeter per kiloyear,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (depth,null,null,centimeter,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleocean earth science/paleoclimate/paleocean earth science/paleoclimate/paleocean earth science/paleoclimate/paleocean (GeoB1023-5>LATITUDE -17.17>LONGITUDE 11.02) Sediment core GeoB 1023-5 from the eastern South Atlantic was investigated at high temporal resolution forvariations of sea-surface temperature (SST) during the past 22 kyr, using the alkenone (UK037 ) method. SSTs increased by 3.5°C from about 18°C during the Last Ice Age (21ū2 cal kyr BP) to about 21.5°C at 14.5 cal kyr BP. This warming trend associated with the deglaciation phase was followed by a cooling event with lowest SSTs near 20°C, persisting forabout 1000 years between 13 and 12 cal kyr BP. The SSTs then continued to increase to about 22.5°C at the Holoceneclimatic optimum at 7 cal kyr BP, and decreased again during the Late Holocene to a core-top value of 19.8°C that iscomparable to modern annual mean SST values. When compared with alkenone SST records from the eastern NorthAtlantic, our SST record indicates continuous warming throughout the deglaciation phase in the Benguela Current,while its northern counterpart, the Canary Current, experienced prominent cooling during `Heinrich Event 1' (H1). Onthe other hand, for the time period corresponding to the `Younger Dryas' (YD) cooling event, the Benguela SST recordexhibits a cold-temperature interval that corresponds to that observed in the eastern North Atlantic SST records. Thisobservation suggests that interhemispheric climate response in Atlantic eastern boundary current systems was differentwith respect to the two abrupt climate events associated with Termination I. For the H1, the eastern South Atlantic SSTrecord strongly supports the hypothesis that an `anti-phase' thermal behavior in South Atlantic surface waters wasforced by the slowdown of the North Atlantic Deep Water formation during cold spells in the North Atlantic. Incontrast, the abrupt cooling in the eastern South Atlantic coincident with the YD period was probably induced by morevigorous global atmospheric circulation, enhancing the upwelling intensity in both eastern boundary current systems.This atmospheric control may have overridden any effect caused by changes in thermohaline circulation on the SouthAtlantic SSTs during the YD, which leads to the assumption that the thermohaline circulation was already much closerto its interglacial mode during the YD than during the H1. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Kim, J.-H. Investigator : Schneider, R.R. Investigator : Mueller, P.J. Investigator : Wefer, G. 2002-07-01 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/8622 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/kim2002 https://www1.ncdc.noaa.gov/pub/data/paleo/paleocean/sediment_files/complete/gb1023-5-tab.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/kim2002 https://www1.ncdc.noaa.gov/pub/data/paleo/paleocean/sediment_files/complete/gb1023-5-tab.txt English https://www.ncdc.noaa.gov/paleo/study/8622 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/kim2002 https://www1.ncdc.noaa.gov/pub/data/paleo/paleocean/sediment_files/complete/gb1023-5-tab.txt Kim, J.-H., R.R. Schneider, P.J. Mueller, and G. Wefer. 2002. Interhemispheric comparison of deglacial sea-surface temperature patterns in Atlantic eastern boundary currents. Earth and Planetary Science Letters, 194, 383-393. START YEAR: 17766 14C yr BP * END YEAR: 310 14C yr BP 11.02 -17.17 11.02 -17.17