{"NOAAStudyId":"23031","contactInfo":{"address":"325 Broadway, E/NE31","city":"Boulder","constraints":"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.","country":"USA","dataCenterUrl":"https://www.ncdc.noaa.gov/data-access/paleoclimatology-data","email":"paleo@noaa.gov","fax":"303-497-6513","longName":"National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce ","phone":"303-497-6280","postalCode":"80305-3328","shortName":"DOC/NOAA/NESDIS/NCEI","state":"CO","type":"CONTACT INFORMATION"},"contributionDate":"2018-04-30","dataPublisher":"NOAA","dataType":"CLIMATE RECONSTRUCTIONS","dataTypeInformation":"https://www.ncdc.noaa.gov/data-access/paleoclimatology-data/datasets/climate-reconstruction","difMetadataLink":"http://www1.ncdc.noaa.gov/pub/data/metadata/published/paleo/dif/xml/noaa-recon-23031.xml","doi":null,"earliestYearBP":1949,"earliestYearCE":1,"entryId":"noaa-recon-23031","funding":[],"investigators":"Werner, J.P.; Divine, D.V.; Ljungqvist, F.C.; Nilsen, T.; Francus, P.","mostRecentYearBP":-52,"mostRecentYearCE":2002,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/23031","originalSource":null,"publication":[{"abstract":"In this article, the first spatially resolved and millennium-length summer (June-August) temperature reconstruction over the Arctic and sub-Arctic domain (north of 60N) is presented. It is based on a set of 44 annually dated temperature-sensitive proxy archives of various types from the revised PAGES2k database supplemented with six new recently updated proxy records. As a major advance, an extension of the Bayesian BARCAST climate field (CF) reconstruction technique provides a means to treat climate archives with dating uncertainties. This results not only in a more precise reconstruction but additionally enables joint probabilistic constraints to be imposed on the chronologies of the used archives. The new seasonal CF reconstruction for the Arctic region can be shown to be skilful for the majority of the terrestrial nodes. The decrease in the proxy data density back in time, however, limits the analyses in the spatial domain to the period after 750 CE, while the spatially averaged reconstruction covers the entire time interval of 1-2002 CE.\r\n\r\nThe centennial to millennial evolution of the reconstructed temperature is in good agreement with a general pattern that was inferred in recent studies for the Arctic and its subregions. In particular, the reconstruction shows a pronounced Medieval Climate Anomaly (MCA; here ca. 920-1060 CE), which was characterised by a sequence of extremely warm decades over the whole domain. The medieval warming was followed by a gradual cooling into the Little Ice Age (LIA), with 1766-1865 CE as the longest centennial-scale cold period, culminating around 1811-1820 CE for most of the target region.\r\n\r\nIn total over 600 independent realisations of the temperature CF were generated. As showcased for local and regional trends and temperature anomalies, operating in a probabilistic framework directly results in comprehensive uncertainty estimates, even for complex analyses. For the presented multi-scale trend analysis, for example, the spread in different paths across the reconstruction ensemble prevents a robust analysis of features at timescales shorter than ca. 30 years. For the spatial reconstruction, the benefit of using the spatially resolved reconstruction ensemble is demonstrated by focusing on the regional expression of the recent warming and the MCA. While our analysis shows that the peak MCA summer temperatures were as high as in the late 20th and early 21st centuries, the spatial coherence of extreme years over the last decades of the reconstruction (1980s onwards) seems unprecedented at least back until 750 CE. However, statistical testing could not provide conclusive support of the contemporary warming to exceed the peak of the MCA in terms of the pan-Arctic mean summer temperatures: the reconstruction cannot be extended reliably past 2002 CE due to lack of proxy data and thus the most recent warming is not captured.","author":{"name":"Johannes P. Werner, Dmitry V. Divine, Fredrik Charpentier Ljungqvist, Tine Nilsen, and Pierre Francus"},"citation":"Johannes P. Werner, Dmitry V. Divine, Fredrik Charpentier Ljungqvist, Tine Nilsen, and Pierre Francus. 2018. Spatio-temporal variability of Arctic summer temperatures over the past 2 millennia. Climate of the Past, 14, 527-557. doi: 10.5194/cp-14-527-2018","edition":null,"identifier":{"id":"10.5194/cp-14-527-2018","type":"doi","url":"http://dx.doi.org/10.5194/cp-14-527-2018"},"issue":null,"journal":"Climate of the Past","pages":"527-557","pubRank":"1","pubYear":2018,"reportNumber":null,"title":"Spatio-temporal variability of Arctic summer temperatures over the past 2 millennia","type":"publication","volume":"14"}],"reconstruction":"Y","scienceKeywords":["Air Temperature Reconstruction"],"site":[{"NOAASiteId":"54080","geo":{"geoType":"Feature","geometry":{"coordinates":["60","90","-180","180"],"type":"POLYGON"},"properties":{"easternmostLongitude":"180","maxElevationMeters":null,"minElevationMeters":null,"northernmostLatitude":"90","southernmostLatitude":"60","westernmostLongitude":"-180"}},"locationName":"Geographic Region>Arctic","mappable":"N","paleoData":[{"NOAADataTableId":"35713","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>reconstructions>air temperature"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/pages2k/werner2018arctic/","linkText":"Arctic2k Gridded Summer Temperature Reconstructions","urlDescription":"Data Folder","variables":[]},{"NOAAKeywords":["earth science>paleoclimate>reconstructions>air temperature"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/pages2k/werner2018arctic/readme-werner2018.txt","linkText":"Arctic2k Gridded Summer Temperature Reconstructions Readme File","urlDescription":"Data Description","variables":[]}],"dataTableName":"Werner2018Arctic","dataTableNotes":null,"earliestYear":1,"earliestYearBP":1949,"earliestYearCE":1,"mostRecentYear":2002,"mostRecentYearBP":-52,"mostRecentYearCE":2002,"species":[],"timeUnit":"AD"}],"siteName":"Arctic"}],"studyCode":null,"studyName":"PAGES2k 2,000 Year Arctic Gridded Temperature Reconstructions","studyNotes":null,"version":"1.0","xmlId":"21376"}