Subpolar North Atlantic 2000 Year Diatom August SST Reconstruction Miettinen, A.; Divine, D.V.; Koç, N.; Godtliebsen, F.; Hall, I.R. Miettinen, A. Divine, D.V. Koç, N. Godtliebsen, F. Hall, I.R. Meridional Overturning Circulation (MOC) PAGES 2k Network PAGES Ocean 2k Sea Surface Temperature Reconstruction earth science/paleoclimate/climate reconstructions|paleoceanography (age,null,null,year Common Era,null,climate reconstructions|paleoceanography,null,null,N,null) earth science/paleoclimate/climate reconstructions|paleoceanography (sea surface temperature,diatom assemblage,null,degree Celsius,Aug,climate reconstructions|paleoceanography,null,null,N,null) earth science/paleoclimate/paleocean earth science/paleoclimate/reconstructions earth science/paleoclimate/paleocean (RAPiD-21-COM>LATITUDE 57.4515>LONGITUDE -27.9088) A 2800-yr-long August sea surface temperature (aSST) record based on fossil diatom assemblages is generated from a marine sediment core from the northern subpolar North Atlantic. The record is compared with the aSST record from the Norwegian Sea to explore the variability of the aSST gradient between these areas during the late Holocene. The aSST records demonstrate the opposite climate tendencies toward a persistent warming in the core site in the subpolar North Atlantic and cooling in the Norwegian Sea. At the multicentennial scale of aSST variability of 600-900 yr, the records are nearly in antiphase with warmer (colder) periods in the subpolar North Atlantic corresponding to the colder (warmer) periods in the Norwegian Sea. At the shorter time scale of 200-450 yr, the records display a phase-locked behavior with a tendency for the positive aSST anomalies in the Norwegian Sea to lead, by ~30 yr, the negative aSST anomalies in the subpolar North Atlantic. This apparent aSST seesaw might have an effect on two major anomalies of the European climate of the past Millennium: Medieval Warm Period (MWP) and the Little Ice Age (LIA). During the MWP warming of the sea surface in the Norwegian Sea occurred in parallel with cooling in the northern subpolar North Atlantic, whereas the opposite pattern emerged during the LIA. The results suggest that the observed aSST seesaw between the subpolar North Atlantic and the Norwegian Sea could be a surface expression of the variability of the eastern and western branches of the Atlantic meridional overturning circulation (AMOC) with a possible amplification through atmospheric feedback. STUDY NOTES: A 2000-year-long (0-2004 AD) August Sea Surface Temperature (aSST) record with high-resolution. The aSST reconstruction is based on fossil diatom assemblages and the weighted averaging partial least squares (WA-PLS) transfer function method. Core Rapid 21-COM represents a composite of two individual sediment cores (Rapid 21-12B and Rapid 21-3K), which were recovered from the southern limb of the Gardar Drift, south of Iceland, during the RRS Charles Darwin cruise 159 in 2004. The age model for core Rapid 21-COM is based on 210Pb dating for the 54.3-cm-long sediment box-core Rapid 21-12B (Boessenkool et al. 2007) and on 14C dating for the 372.5-cm-long kasten core Rapid 21-3K (Boessenkool et al. 2007; Sicre et al. 2011). The previously published diatom-based aSST record from core Rapid 21–12B has 2-yr-average resolution for the last 230 years (Miettinen et al. 2011). Core Rapid 21-3K was sampled continuously at 1.0-cm intervals and analyzed at 1- to 5-cm intervals with a resolution of 8-10 yr for the interval AD 800-1770, representing the highest-resolution diatom SST reconstruction from the subpolar North Atlantic for this period, and 40 yr for interval 0-AD 800. Composite core Rapid 21-COM: 57°27.09'N, 27°54.53'W, 2,630 m water depth NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Miettinen, A. Investigator : Divine, D.V. Investigator : Koç, N. Investigator : Godtliebsen, F. Investigator : Hall, I.R. 2012-04-24 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/12905 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/miettinen2012/miettinen2012.xls https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/miettinen2012/miettinen2012.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/miettinen2012/miettinen2012.xls https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/miettinen2012/miettinen2012.txt English https://www.ncdc.noaa.gov/paleo/study/12905 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/miettinen2012/miettinen2012.xls https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/miettinen2012/miettinen2012.txt Miettinen, A., D. Divine, N. Koç¸ F. Godtliebsen, and I.R. Hall2012Multicentennial variability of the sea surface temperature gradient across the subpolar North Atlantic over the last 2.8 kyrJournal of Climate25124205-421910.1175/JCLI-D-11-00581.1 START YEAR: 2 AD * END YEAR: 2004 AD -27.9088 57.4515 -27.9088 57.4515