Northern Hemisphere 1000 Year Multiproxy Temperature Reconstruction Shi, F.; Yang, B.; Mairesse, A.; von Gunten, L.; Li, J.; Bräuning, A.; Yang, F.; Xiao, X. Shi, F. Yang, B. Mairesse, A. von Gunten, L. Li, J. Bräuning, A. Yang, F. Xiao, X. Air Temperature Reconstruction earth science/paleoclimate/climate reconstructions (surface temperature,multiple proxies,null,degree Celsius,annual,climate reconstructions,anomalized|smoothed,principal component analysis,N,PC10+AR2; smoothed loess 0.01; anomalized 1961-1990 A.D.) earth science/paleoclimate/climate reconstructions (surface temperature,multiple proxies,null,degree Celsius,annual,climate reconstructions,anomalized|smoothed,regression analysis,N,anomalized 1961-1990 AD; regularized errors-in-variables) earth science/paleoclimate/climate reconstructions (surface temperature,multiple proxies,range upper bound,degree Celsius,annual,climate reconstructions,anomalized|smoothed,principal component analysis,N,PC10+AR2; smoothed loess 0.01; anomalized 1961-1990 A.D.) earth science/paleoclimate/instrumental (surface temperature,null,null,degree Celsius,annual,instrumental,anomalized|smoothed,null,N,CRUTEM3v; anomalized from 1961-1990 AD) earth science/paleoclimate/climate reconstructions (age,null,null,year Common Era,null,climate reconstructions,null,null,N,null) earth science/paleoclimate/climate reconstructions (surface temperature,multiple proxies,range lower bound,degree Celsius,annual,climate reconstructions,anomalized|smoothed,principal component analysis,N,PC10+AR2; smoothed loess 0.01; anomalized 1961-1990 A.D.) earth science/paleoclimate/climate reconstructions (surface temperature,multiple proxies,null,degree Celsius,annual,climate reconstructions,anomalized|smoothed,composite plus scale,N,anomalized 1961-1990 AD) earth science/paleoclimate/reconstructions (Northern Hemisphere>LATITUDE >LONGITUDE ) Previous studies have either exclusively used annual tree-ring data or have combined tree-ring series with other, lower temporal resolution proxy series. Both approaches can lead to significant uncertainties, as tree-rings may underestimate the amplitude of past temperature variations, and the validity of non-annual records cannot be clearly assessed. In this study, we assembled 45 published Northern Hemisphere (NH) temperature proxy records covering the past millennium, each of which satisfied 3 essential criteria: the series must be of annual resolution, span at least a thousand years, and represent an explicit temperature signal. Suitable climate archives included ice cores, varved lake sediments, tree-rings and speleothems. We reconstructed the average annual land temperature series for the NH over the last millennium by applying 3 different reconstruction techniques: (1) principal components (PC) plus second-order autoregressive model (AR2), (2) composite plus scale (CPS) and (3) regularized errors-in-variables approach (EIV). Our reconstruction is in excellent agreement with 6 climate model simulations (including the first 5 models derived from the fifth phase of the Coupled Model Intercomparison Project (CMIP5) and an earth system model of intermediate complexity (LOVECLIM), showing similar temperatures at multi-decadal timescales; however, all simulations appear to underestimate the temperature during the Medieval Warm Period (MWP). A comparison with other NH reconstructions shows that our results are consistent with earlier studies. These results indicate that well-validated annual proxy series should be used to minimize proxy-based artifacts, and that these proxy series contain sufficient information to reconstruct the low-frequency climate variability over the past millennium. STUDY NOTES: Northern Hemisphere 1000 year annual temperature reconstructions based on 45 published temperature proxy records, including ice core, varved lake sediments, tree-rings and speleothem records. The average annual land temperature series for the NH over the last millennium was reconstructed by 3 different reconstruction techniques: (1) 10 principal components (PC10+AR2) plus second-order autoregressive model (AR2), (2) composite plus scale (CPS), and (3) regularized errors-in-variables approach (EIV). Figure 2 data are Northern Hemisphere (NH) land temperature anomalies (with respect to AD 1961-1990) over the last 1000 yr reconstructed with PC10+AR2 (red solid line), CPS (black solid line) and EIV (blue dashed line). The 3 reconstruction results were smoothed by the loess method (span: 0.01). All models were fitted to the period AD 1850-1998 and reconstructed for AD 998-1849. Figure 4 data are with 0.05 filtered values for AD 1001-1960. Every series was firstly expressed as anomalies from AD 1850-1960, and was then variance matched using the instrumental data from AD 1850-1960. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Shi, F. Investigator : Yang, B. Investigator : Mairesse, A. Investigator : von Gunten, L. Investigator : Li, J. Investigator : Bräuning, A. Investigator : Yang, F. Investigator : Xiao, X. 2013-04-24 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/14250 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/shi2013/shi2013nh.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/shi2013/shi2013nh.txt English https://www.ncdc.noaa.gov/paleo/study/14250 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/shi2013/shi2013nh.txt Feng Shi, Bao Yang, Aurèlien Mairesse, Lucien von Gunten, Jianping Li, Achim Bräuning, Fengmei Yang, Xia Xiao. 2013. Northern Hemisphere temperature reconstruction during the last millennium using multiple annual proxies. Climate Research, Vol. 56, Issue 3, pp. 231-244. DOI: 10.3354/cr01156 START YEAR: 1000 AD * END YEAR: 2009 AD -180 0 180 90