Kaufman et al. 2009 2,000 Year Arctic Temperature Synthesis Kaufman, D.S.; Schneider, D.P.; McKay, N.P.; Ammann, C.M.; Bradley, R.S.; Briffa, K.R.; Miller, G.H.; Otto-Bliesner, B.L.; Overpeck, J.T.; Vinther, B.M. Kaufman, D.S. Schneider, D.P. McKay, N.P. Ammann, C.M. Bradley, R.S. Briffa, K.R. Miller, G.H. Otto-Bliesner, B.L. Overpeck, J.T. Vinther, B.M. Air Temperature Reconstruction earth science/paleoclimate/climate reconstructions (proxy composite,multiple proxies,null,standard deviation unit,null,climate reconstructions,composited|normalized,null,N,null) earth science/paleoclimate/paleolimnology (organic matter,sediment,null,standard deviation unit,null,paleolimnology,normalized,null,N,null) earth science/paleoclimate/paleolimnology (absorbance,null,null,standard deviation unit,null,paleolimnology,normalized,x-ray densitometry,N,null) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Gulf of Alaska) earth science/paleoclimate/ice cores (delta 18O,bulk ice,null,standard deviation unit,null,ice cores,normalized,null,N,NGRIP) earth science/paleoclimate/paleolimnology (varve thickness,null,null,standard deviation unit,null,paleolimnology,normalized,null,N,null) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Avam-Taimyr) earth science/paleoclimate/climate reconstructions|paleolimnology (age,null,null,year Common Era,null,climate reconstructions|paleolimnology,null,null,N,null) earth science/paleoclimate/ice cores (delta 18O,bulk ice,null,standard deviation unit,null,ice cores,normalized,null,N,DYE-3) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Fennoscandia) earth science/paleoclimate/ice cores (delta 18O,bulk ice,null,standard deviation unit,null,ice cores,normalized,null,N,Crete) earth science/paleoclimate/climate reconstructions (temperature,multiple proxies,null,degree Celsius,Jun-Aug,climate reconstructions,anomalized,null,N,null) earth science/paleoclimate/ice cores (delta 18O,bulk ice,null,standard deviation unit,null,ice cores,normalized,null,N,Agassiz) earth science/paleoclimate/ice cores (delta 18O,bulk ice,null,standard deviation unit,null,ice cores,normalized,null,N,GRIP) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,Yamal) earth science/paleoclimate/climate reconstructions|paleolimnology (proxy composite,null,null,standard deviation unit,null,climate reconstructions|paleolimnology,corrected|smoothed,null,N,null) earth science/paleoclimate/ice cores (delta 18O,bulk ice,null,standard deviation unit,null,ice cores,normalized,null,N,Renland) earth science/paleoclimate/paleolimnology (biogenic silica,sediment,null,standard deviation unit,null,paleolimnology,normalized,null,N,null) earth science/paleoclimate/ice cores (delta 18O,bulk ice,null,standard deviation unit,null,ice cores,normalized,null,N,Devon ice core) earth science/paleoclimate/paleolimnology (varve thickness,null,null,standard deviation unit,null,paleolimnology,normalized,null,N,varve organic layer thickness) earth science/paleoclimate/reconstructions (Arctic>LATITUDE >LONGITUDE ) The temperature history of the first millennium C.E. is sparsely documented, especially in the Arctic. We present a synthesis of decadally resolved proxy temperature records from poleward of 60°N covering the past 2000 years, which indicates that a pervasive cooling in progress 2000 years ago continued through the Middle Ages and into the Little Ice Age. A 2000-year transient climate simulation with the Community Climate System Model shows the same temperature sensitivity to changes in insolation as does our proxy reconstruction, supporting the inference that this long-term trend was caused by the steady orbitally driven reduction in summer insolation. The cooling trend was reversed during the 20th century, with four of the five warmest decades of our 2000-year-long reconstruction occurring between 1950 and 2000. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Kaufman, D.S. Investigator : Schneider, D.P. Investigator : McKay, N.P. Investigator : Ammann, C.M. Investigator : Bradley, R.S. Investigator : Briffa, K.R. Investigator : Miller, G.H. Investigator : Otto-Bliesner, B.L. Investigator : Overpeck, J.T. Investigator : Vinther, B.M. 2009-07-01 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/8700 https://www1.ncdc.noaa.gov/pub/data/paleo/reconstructions/arctic/kaufman2009arctic.xls https://www1.ncdc.noaa.gov/pub/data/paleo/reconstructions/arctic/kaufman2009arctic.txt https://www1.ncdc.noaa.gov/pub/data/paleo/reconstructions/arctic/kaufman2009arctic.xls https://www1.ncdc.noaa.gov/pub/data/paleo/reconstructions/arctic/kaufman2009arctic.txt English https://www.ncdc.noaa.gov/paleo/study/8700 https://www1.ncdc.noaa.gov/pub/data/paleo/reconstructions/arctic/kaufman2009arctic.xls https://www1.ncdc.noaa.gov/pub/data/paleo/reconstructions/arctic/kaufman2009arctic.txt Kaufman, D.S., Schneider, D.P., McKay, N.P., Ammann, C.M., Bradley, R.S., Briffa K.R., Miller, G.H., Otto-Bliesner, B.L., Overpeck, J.T., Vinther, B.M., Arctic Lakes 2k Project Members (Abbott, M., Axford, Y., Bird, B., Birks, H.J.B., Bjune, A.E., Briner, J., Cook, T., Chipman, M., Francus, P., Gajewski, K., Geirsdóttir, Á., Hu, F.S., Kutchko, B., Lamoureux, S., Loso, M., MacDonald, G., Peros, M., Porinchu, D., Schiff, C., Seppä, H., Thomas, E.). 2009. Recent Warming Reverses Long-Term Arctic Cooling. Science, Vol. 325, pp. 1236-1239. DOI: 10.1126/science.1173983 START YEAR: 5 AD * END YEAR: 1995 AD -180 60 180 90