North Atlantic SST and Salinity Reconstructions over the Past Millennium Moffa-Sánchez, P.; Born, A.; Hall, I.R.; Thornalley, D.J.R.; Barker, S. Moffa-Sánchez, P. Born, A. Hall, I.R. Thornalley, D.J.R. Barker, S. Other Hydroclimate Reconstruction Sea Surface Temperature Reconstruction earth science/paleoclimate/paleoceanography (depth,null,null,millimeter,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (delta 18O,Globorotalia inflata,null,per mil PDB,null,paleoceanography,null,isotope ratio mass spectrometry,N,null) earth science/paleoclimate/climate reconstructions|paleoceanography (delta 18O,delta 18O|magnesium/calcium|sea water,null,per mil SMOW,null,climate reconstructions|paleoceanography,null,null,N,using G. inflata) earth science/paleoclimate/paleoceanography (magnesium/calcium,Globorotalia inflata,null,millimole per mole,null,paleoceanography,null,isotope ratio mass spectrometry,N,null) earth science/paleoclimate/climate reconstructions|paleoceanography (sea surface temperature,magnesium/calcium,null,degree Celsius,null,climate reconstructions|paleoceanography,null,null,N,using Thornalley et al.(2009)) earth science/paleoclimate/climate reconstructions|paleoceanography (salinity,delta 18O|magnesium/calcium|sea surface,null,practical salinity unit,null,climate reconstructions|paleoceanography,null,null,N,using G. inflata) earth science/paleoclimate/paleoceanography (age,null,null,year Common Era,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleocean earth science/paleoclimate/paleocean earth science/paleoclimate/paleocean (RAPiD-35-25B>LATITUDE 57.507833>LONGITUDE -48.723333) (RAPiD-17-5P>LATITUDE 61.481667>LONGITUDE -19.536) There were several centennial-scale fluctuations in the climate and oceanography of the North Atlantic region over the past 1,000 years, including a period of relative cooling from about AD 1450 to 1850 known as the Little Ice Age1. These variations may be linked to changes in solar irradiance, amplified through feedbacks including the Atlantic meridional overturning circulation2. Changes in the return limb of the Atlantic meridional overturning circulation are reflected in water properties at the base of the mixed layer south of Iceland. Here we reconstruct thermocline temperature and salinity in this region from AD 818 to 1780 using paired d18O and Mg/Ca ratio measurements of foraminifer shells from a subdecadally resolved marine sediment core. The reconstructed centennial-scale variations in hydrography correlate with variability in total solar irradiance. We find a similar correlation in a simulation of climate over the past 1,000 years. We infer that the hydrographic changes probably reflect variability in the strength of the subpolar gyre associated with changes in atmospheric circulation. Specifically, in the simulation, low solar irradiance promotes the development of frequent and persistent atmospheric blocking events, in which a quasi-stationary high-pressure system in the eastern North Atlantic modifies the flow of the westerly winds. We conclude that this process could have contributed to the consecutive cold winters documented in Europe during the Little Ice Age. STUDY NOTES: Provided Keywords: Last millennium, Subpolar North Atlantic NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Moffa-Sánchez, P. Investigator : Born, A. Investigator : Hall, I.R. Investigator : Thornalley, D.J.R. Investigator : Barker, S. 2016-02-22 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/19804 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/moffa-sanchez2014-ngs/moffa-sanchez2014-ngs-17-5p.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/moffa-sanchez2014-ngs/moffa-sanchez2014-ngs-35-25b.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/moffa-sanchez2014-ngs/moffa-sanchez2014-ngs-17-5p.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/moffa-sanchez2014-ngs/moffa-sanchez2014-ngs-35-25b.txt English https://www.ncdc.noaa.gov/paleo/study/19804 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/moffa-sanchez2014-ngs/moffa-sanchez2014-ngs-17-5p.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/moffa-sanchez2014-ngs/moffa-sanchez2014-ngs-35-25b.txt Moffa-Sanchez, P., A. Born, I.R. Hall, D.J.R. Thornalley, and S. Barker2014Solar forcing of North Atlantic surface temperature and salinity over the past millenniumNature Geoscience7275-27810.1038/ngeo2094http://www.nature.com/ngeo/journal/v7/n4/abs/ngeo2094.html START YEAR: 763 AD * END YEAR: 1914 AD -48.723333 57.507833 -19.536 61.481667