noaa-recon-9924 Northern Hemisphere Extra-Tropics 2,000yr Decadal Temperature Reconstruction Ljungqvist, F.C. Northern Hemisphere Extra-Tropics 2,000yr Decadal Temperature Reconstruction 2010-08-31 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/9924 Investigator F.C. Ljungqvist earth science paleoclimate climate reconstructions temperature,multiple proxies,two standard deviations lower bound,degree Celsius,null,climate reconstructions,anomalized,null,N,null earth science paleoclimate climate reconstructions temperature,multiple proxies,two standard deviations upper bound,degree Celsius,null,climate reconstructions,anomalized,null,N,null earth science paleoclimate climate reconstructions age,null,null,year Common Era,null,climate reconstructions,null,null,N,mid-point of decade earth science paleoclimate climate reconstructions temperature,multiple proxies,null,degree Celsius,null,climate reconstructions,anomalized,null,N,anomalized wrt 1961-1990 earth science paleoclimate instrumental temperature,null,null,degree Celsius,null,instrumental,anomalized,null,N,Instrumental temperature data from the variance adjusted CRUTEM3+HadSST2 90–30°N data set earth science paleoclimate reconstructions air temperature geoscientificInformation Air Temperature Reconstruction decadal resolution 0 AD 1999 AD 1950 cal yr BP -49 cal yr BP Complete 0 90 -180 180 Geographic Region Northern Hemisphere Northern Hemisphere>LATITUDE >LONGITUDE None Please cite original publication, online resource, dataset and publication DOIs (where available), and date accessed when using downloaded data. If there is no publication information, please cite investigator, title, online resource, and date accessed. The appearance of external links associated with a dataset does not constitute endorsement by the Department of Commerce/National Oceanic and Atmospheric Administration of external Web sites or the information, products or services contained therein. For other than authorized activities, the Department of Commerce/NOAA does not exercise any editorial control over the information you may find at these locations. These links are provided consistent with the stated purpose of this Department of Commerce/NOAA Web site. English DOC/NOAA/NESDIS/NCEI National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce https://www.ncdc.noaa.gov/data-access/paleoclimatology-data DATA Center Contact Bruce Bauer bruce.a.bauer@noaa.gov paleo@noaa.gov 303-497-6280 303-497-6513

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Boulder CO 80305-3328 USA online ASCII Ljungqvist, F.C. 2010. A new reconstruction of temperature variability in the extra-tropical Northern Hemisphere during the last two millennia. Geografiska Annaler: Physical Geography, Vol. 92 A(3), pp. 339-351, September 2010. DOI: 10.1111/j.1468-0459.2010.00399.x

A new temperature reconstruction with decadal resolution, covering the last two millennia, is presented for the extratropical Northern Hemisphere (90-30°N), utilizing many palaeotemperature proxy records never previously included in any large-scale temperature reconstruction. The amplitude of the reconstructed temperature variability on centennial time-scales exceeds 0.6°C. This reconstruction is the first to show a distinct Roman Warm Period c. AD 1-300, reaching up to the 1961-1990 mean temperature level, followed by the Dark Age Cold Period c. AD 300- 800. The Medieval Warm Period is seen c. AD 800–1300 and the Little Ice Age is clearly visible c. AD 1300-1900, followed by a rapid temperature increase in the twentieth century. The highest average temperatures in the reconstruction are encountered in the mid to late tenth century and the lowest in the late seventeenth century. Decadal mean temperatures seem to have reached or exceeded the 1961-1990 mean temperature level during substantial parts of the Roman Warm Period and the Medieval Warm Period. The temperature of the last two decades, however, is possibly higher than during any previous time in the past two millennia, although this is only seen in the instrumental temperature data and not in the multi-proxy reconstruction itself. Our temperature reconstruction agrees well with the reconstructions by Moberg et al. (2005) and Mann et al. (2008) with regard to the amplitude of the variability as well as the timing of warm and cold periods, except for the period c. AD 300-800, despite significant differences in both data coverage and methodology. STUDY NOTES: Multi-proxy temperature reconstruction for the extra-tropical Northern Hemisphere (90-30°N) during the last two millennia based on 30 palaeotemperature proxy records with annual to multi-decadal resolution. Proxy types include historical documentary records, seafloor sediment records, lake sediment records, speleothem records, ice-core records, varved thickness sediment records, tree-ring width and maximum latewood density records. The reconstruction is presented as decadal anomalies in degrees C relative to the 1961–1990 reference period and provided with quantitative error bars.

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/ljungqvist2010/ljungqvist2010.xls GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/ljungqvist2010/ljungqvist2010.txt USA/NOAA DIF Version 9.8.4 2019-03-07 2019-03-07