Norwegian Sea Diatom SST Reconstruction for the last 2,000 Years Berner, K.S.; Koç, N.; Godtliebsen, F.; Divine, D.V. Berner, K.S. Koç, N. Godtliebsen, F. Divine, D.V. Sea Surface Temperature Reconstruction earth science/paleoclimate/climate reconstructions|paleoceanography (depth,null,null,centimeter,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,regression analysis,N,weighted-averaging partial least-squares regression) earth science/paleoclimate/climate reconstructions|paleoceanography (age,null,null,year Common Era,null,climate reconstructions|paleoceanography,null,null,N,null) earth science/paleoclimate/reconstructions (Vøring Plateau>LATITUDE 66.97>LONGITUDE 7.64) A high-resolution sediment core from the Vøring Plateau has been studied to document the centennial to millennial variability of the surface water conditions during the Holocene Climate Optimum (HCO) and the late Holocene period (LHP) in order to evaluate the effects of solar insolation on surface ocean climatology. Quantitative August summer sea surface temperatures (SSSTs) with a time resolution of 2–40 years are reconstructed by using three different diatom transfer function methods. Spectral- and scale-space methods are applied to the records to explore the variability present in the time series at different time scales. The SSST development in core MD95-2011 shows a delayed response to Northern Hemisphere maximum summer insolation at ca. 11,000 years B.P. The record shows the maximum SSST of the HCO to be from 7.3 to 8.9 kyr B.P., which implies that the site was located in the regional warm water pool removed from the oceanic fronts and Arctic waters. Superimposed on the general cooling trendare higher-frequency variabilities at time scales of 80–120, 210–320, 320–640, and 640–1280 years. The climate variations at the time scale of 320–640 years are documented both for periods of high and low solar orbital insolation. We found evidence that the submillennial-scale mode of variability (640–900 years) in SSST evident during the LHP is directly associated with varying solar forcing. At the shorter scale of 260–450 years, the SSST during the LHP displays a lagged response to solar forcing with a phase-locked behavior indicating the existence of a feedback mechanism in the climate system triggered by variations in the solar constant as well as the role of the thermal inertia of the ocean. The abruptness of the cooling events in the LHP, especially pronounced during the onsets of the Holocene Cold Period I (approximately 2300 years B.P.) and the Little Ice Age (approximately 550 years B.P.), can be explained by a shutdown of deep convection in the Nordic Seas in response to negative solar insolation anomalies. These cooling events are on the order of 1.5°C. STUDY NOTES: A 2000-year-long diatom inferred August sea surface temperature reconstruction, with 2-13 year resolution, from marine sediment core CR 948/2011 from the Vøring Plateau, Norwegian Sea. The composite core CR 948/2011 consists of the calypso core MD95-2011 and the boxcore JM97-948/2A. A modern training set consisting of 139 surface samples with 52 diatom species from the Nordic Seas and the North Atlantic was utilized to convert downcore diatom counts to quantitative August SST using the weighted averaging partial least squares (WA-PLS) transfer function method. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Berner, K.S. Investigator : Koç, N. Investigator : Godtliebsen, F. Investigator : Divine, D.V. 2014-11-26 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/17475 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/berner2011/berner2011.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/berner2011/berner2011.txt English https://www.ncdc.noaa.gov/paleo/study/17475 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/berner2011/berner2011.txt Berner, K.S., N. Koç, F. Godtliebsen, and D. Divine2011Holocene climate variability of the Norwegian Atlantic Current during high and low solar insolation forcingPaleoceanography26PA222010.1029/2010PA002002 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 Climate254205-421910.1175/JCLI-D-11-00581.1 START YEAR: 4 AD * END YEAR: 1995 AD 7.64 66.97 7.64 66.97