North America Last 2ka Decadal Temperature Reconstructions Trouet, V.; Diaz, H.F.; Wahl, E.R.; Viau, A.E.; Graham, R.; Graham, N.E.; Cook, E.R. Trouet, V. Diaz, H.F. Wahl, E.R. Viau, A.E. Graham, R. Graham, N.E. Cook, E.R. Air Temperature Reconstruction PAGES 2k Network PAGES NAmerica 2k temperature earth science/paleoclimate/climate reconstructions|tree ring (age,null,null,year Common Era,null,climate reconstructions|tree ring,null,null,N,null) earth science/paleoclimate/climate reconstructions|tree ring (surface air temperature,ring width,percentile,degree Celsius,annual,climate reconstructions|tree ring,anomalized,regression analysis,N,16th percentile; wrt 1904-1980; simple linear regression; 2m air temperature) earth science/paleoclimate/climate reconstructions|tree ring (surface air temperature,ring width,null,degree Celsius,annual,climate reconstructions|tree ring,anomalized,regression analysis,N,wrt 1904-1980; principal components spatial regression; 2m air temperature) earth science/paleoclimate/climate reconstructions|tree ring (surface air temperature,ring width,percentile,degree Celsius,annual,climate reconstructions|tree ring,anomalized,regression analysis,N,97.5th percentile; wrt 1904-1980; principal components spatial regression; 2m air temperature) earth science/paleoclimate/climate reconstructions|pollen (age,null,null,year Common Era,null,climate reconstructions|pollen,null,null,N,null) earth science/paleoclimate/climate reconstructions|tree ring (surface air temperature,ring width,percentile,degree Celsius,annual,climate reconstructions|tree ring,anomalized,regression analysis,N,2.5th percentile; wrt 1904-1980; principal components spatial regression; 2m air temperature) earth science/paleoclimate/climate reconstructions|tree ring (surface air temperature,ring width,percentile,degree Celsius,annual,climate reconstructions|tree ring,anomalized,regression analysis,N,0.5th percentile; wrt 1904-1980; simple linear regression; 2m air temperature) earth science/paleoclimate/climate reconstructions|pollen (surface air temperature,null,two standard error lower bound,degree Celsius,annual,climate reconstructions|pollen,anomalized,principal component analysis|regression analysis,N,wrt 1904-1980; principal components regression; 2m air temperature) earth science/paleoclimate/climate reconstructions|tree ring (surface air temperature,ring width,null,degree Celsius,annual,climate reconstructions|tree ring,anomalized,regression analysis,N,wrt 1904-1980; simple linear regression; 2m air temperature) earth science/paleoclimate/climate reconstructions|tree ring (surface air temperature,ring width,percentile,degree Celsius,annual,climate reconstructions|tree ring,anomalized,regression analysis,N,99.5th percentile; wrt 1904-1980; simple linear regression; 2m air temperature) earth science/paleoclimate/climate reconstructions|pollen (surface air temperature,null,one standard error upper bound,degree Celsius,annual,climate reconstructions|pollen,anomalized,principal component analysis|regression analysis,N,wrt 1904-1980; principal components regression; 2m air temperature) earth science/paleoclimate/climate reconstructions|tree ring (surface air temperature,ring width,percentile,degree Celsius,annual,climate reconstructions|tree ring,anomalized,regression analysis,N,5th percentile; wrt 1904-1980; simple linear regression; 2m air temperature) earth science/paleoclimate/climate reconstructions|tree ring (surface air temperature,ring width,percentile,degree Celsius,annual,climate reconstructions|tree ring,anomalized,regression analysis,N,97.5th percentile; wrt 1904-1980; simple linear regression; 2m air temperature) earth science/paleoclimate/climate reconstructions|pollen (surface air temperature,null,null,degree Celsius,annual,climate reconstructions|pollen,anomalized,principal component analysis|regression analysis,N,wrt 1904-1980; principal components regression; 2m air temperature) earth science/paleoclimate/climate reconstructions|pollen (surface air temperature,null,one standard error lower bound,degree Celsius,annual,climate reconstructions|pollen,anomalized,principal component analysis|regression analysis,N,wrt 1904-1980; principal components regression; 2m air temperature) earth science/paleoclimate/climate reconstructions|tree ring (surface air temperature,ring width,percentile,degree Celsius,annual,climate reconstructions|tree ring,anomalized,regression analysis,N,2.5th percentile; wrt 1904-1980; simple linear regression; 2m air temperature) earth science/paleoclimate/climate reconstructions|tree ring (surface air temperature,ring width,percentile,degree Celsius,annual,climate reconstructions|tree ring,anomalized,regression analysis,N,84th percentile; wrt 1904-1980; simple linear regression; 2m air temperature) earth science/paleoclimate/climate reconstructions|tree ring (surface air temperature,ring width,percentile,degree Celsius,annual,climate reconstructions|tree ring,anomalized,regression analysis,N,95th percentile; wrt 1904-1980; simple linear regression; 2m air temperature) earth science/paleoclimate/climate reconstructions|pollen (surface air temperature,null,two standard error upper bound,degree Celsius,annual,climate reconstructions|pollen,anomalized,principal component analysis|regression analysis,N,wrt 1904-1980; principal components regression; 2m air temperature) earth science/paleoclimate/reconstructions (Temperate North America>LATITUDE >LONGITUDE ) Past global climate changes had strong regional expression. To elucidate their spatio-temporal pattern, we reconstructed past temperatures for seven continental-scale regions during the past one to two millennia. The most coherent feature in nearly all of the regional temperature reconstructions is a long-term cooling trend, which ended late in the nineteenth century. At multi-decadal to centennial scales, temperature variability shows distinctly different regional patterns, with more similarity within each hemisphere than between them. There were no globally synchronous multi-decadal warm or cold intervals that define a worldwide Medieval Warm Period or Little Ice Age, but all reconstructions show generally cold conditions between ad 1580 and 1880, punctuated in some regions by warm decades during the eighteenth century. The transition to these colder conditions occurred earlier in the Arctic, Europe and Asia than in North America or the Southern Hemisphere regions. Recent warming reversed the long-term cooling; during the period ad 1971-2000, the area-weighted average reconstructed temperature was higher than any other time in nearly 1,400 years. STUDY NOTES: PAGES North America 2k Temperature Reconstructions, including tree-ring based reconstructions at annual and decadal resolution (1200-1980 CE), plus a pollen-based reconstruction at 30 year resolution (480-1950 CE). NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Trouet, V. Investigator : Diaz, H.F. Investigator : Wahl, E.R. Investigator : Viau, A.E. Investigator : Graham, R. Investigator : Graham, N.E. Investigator : Cook, E.R. 2014-03-30 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/16257 https://www1.ncdc.noaa.gov/pub/data/paleo/pages2k/trouet2013nam480pollen.txt https://www1.ncdc.noaa.gov/pub/data/paleo/pages2k/trouet2013nam1200tr-ann.txt https://www1.ncdc.noaa.gov/pub/data/paleo/pages2k/trouet2013nam1200tr-dec.txt https://www1.ncdc.noaa.gov/pub/data/paleo/pages2k/trouet2013nam480pollen.txt https://www1.ncdc.noaa.gov/pub/data/paleo/pages2k/trouet2013nam1200tr-ann.txt https://www1.ncdc.noaa.gov/pub/data/paleo/pages2k/trouet2013nam1200tr-dec.txt English https://www.ncdc.noaa.gov/paleo/study/16257 https://www1.ncdc.noaa.gov/pub/data/paleo/pages2k/trouet2013nam480pollen.txt https://www1.ncdc.noaa.gov/pub/data/paleo/pages2k/trouet2013nam1200tr-ann.txt https://www1.ncdc.noaa.gov/pub/data/paleo/pages2k/trouet2013nam1200tr-dec.txt Trouet, V., H.F. Diaz, E.R. Wahl, A. Viau, R. Graham, N. Graham, and E.R. Cook2013A 1500-Year Reconstruction of Annual Mean Temperature for Temperate North America on Decadal-to-Multidecadal Time ScalesEnvironmental Research Letters8202400810.1088/1748-9326/8/2/024008http://iopscience.iop.org/1748-9326/8/2/024008/article PAGES 2k Consortium. 2013. Continental-scale temperature variability during the past two millennia. Nature Geoscience, Vol. 6, pp. 339-346, May 2013. www.nature.com/naturegeoscience DOI: 10.1038/NGEO1797 START YEAR: 480 AD * END YEAR: 1987 AD -130 30 -75 55