Scoop Lake, South Greenland 3000 Year Chironomid d18O and Temperature Lasher, G.E.; Axford, Y. Lasher, G.E. Axford, Y. earth science/paleoclimate/paleolimnology (Scoop Lake>LATITUDE 60.697>LONGITUDE -45.419) Recent work has documented glacier advances in West Greenland coincident with the Medieval Climate Anomaly (MCA) and warmth across much of northern Europe. The North Atlantic Oscillation (NAO) has been invoked to explain antiphasing of temperatures between these North Atlantic regions. Historical and model observations suggest negative correlation between the mode of NAO and both temperature and d18O values of precipitation over much of Greenland. We test for a hypothesized positive NAO mode and associated cool conditions during the MCA in South Greenland within the Norse Eastern Settlement by reconstructing d18O values of precipitation at subcentennial resolution over the past 3000 yr using aquatic insect subfossils preserved in lake sediments. More positive d18O values are found between 900 and 1400 CE, indicating a period of warmth in South Greenland superimposed on late Holocene insolation-forced Neoglacial cooling, and thus not supporting a positive NAO anomaly during the MCA. Highly variable d18O values record an unstable climate at the end of the MCA, preceding Norse abandonment of Greenland. The spatial pattern of paleoclimate in this region supports proposals that North Atlantic subpolar ocean currents modulated South Greenland's climate over the past 3000 yr, particularly during the MCA. Terrestrial climate in the Labrador Sea and Baffin Bay regions may be spatially heterogeneous on centennial time scales due in part to the influence of the subpolar gyre. STUDY NOTES: Oxygen isotope record measured on chironomid head capsule macrofossils. Paleo lake water is inferred from chironomid d18O values NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Lasher, G.E. Investigator : Axford, Y. 2019-02-11 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/26170 https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/greenland/scoop2019.txt https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/greenland/scoop2019.txt English https://www.ncdc.noaa.gov/paleo/study/26170 https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/greenland/scoop2019.txt Lasher, G. Everett; Axford, Yarrow2019Medieval warmth confirmed at the Norse Eastern Settlement in GreenlandGeology10.1130/G45833.1https://pubs.geoscienceworld.org/gsa/geology/article-abstract/568708/medieval-warmth-confirmed-at-the-norse-eastern START YEAR: 2782 cal yr BP * END YEAR: -66 cal yr BP -45.419 60.697 -45.419 60.697