{"NOAAStudyId":"20652","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":"2016-10-28","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-20652.xml","doi":null,"earliestYearBP":705,"earliestYearCE":1245,"entryId":"noaa-recon-20652","funding":[{"fundingAgency":"Natural Sciences and Engineering Research Council of Canada","fundingGrant":"Discovery Grant"}],"investigators":"Porter, T.J.; Pisaric, M.; Kokelj, S.; deMontigny, P.","mostRecentYearBP":-57,"mostRecentYearCE":2007,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/20652","originalSource":null,"publication":[{"abstract":"We present a reconstruction of June-July minimum temperatures since AD 1245 for the Mackenzie Delta region based on a 29-site network of white spruce (Picea glauca) ring-width series. Most but not all trees experienced a divergent temperature-growth response, similar to the divergence that has affected other white spruce trees across Yukon and Alaska. However, divergence in the study region began as early as AD 1900 and we have documented our methods to avoid including divergent signals in the reconstruction. Calibration/verification testing based on local temperature data, and multi-century coherence with nearby and large-scale temperature proxy records, confirm that our reconstruction is robust. The reconstruction shows cool conditions in the late 13th, early 18th and early 19th centuries, corresponding with solar minima and increased volcanism. These cool periods are interrupted by warm periods consistent with early to mid-20th century warmth. The late 20th century is the warmest interval, and the last decade is estimated to be 1.4C warmer than any decade before the mid-20th century. The reconstructed climate history corroborates other proxy-based inferences and supports the notion that high-latitude regions such as the Mackenzie Delta have experienced rapid warming in recent decades that is exceptional in the last eight centuries.","author":{"name":"Trevor J. Porter, Michael F.J. Pisaric, Steven V. Kokelj, Peter deMontigny"},"citation":"Trevor J. Porter, Michael F.J. Pisaric, Steven V. Kokelj, Peter deMontigny. 2013. A ring-width-based reconstruction of June-July minimum temperatures since AD 1245 from white spruce stands in the Mackenzie Delta region, northwestern Canada. Quaternary Research, 80(2), 167-179. doi: 10.1016/j.yqres.2013.05.004","edition":null,"identifier":{"id":"10.1016/j.yqres.2013.05.004","type":"doi","url":"http://dx.doi.org/10.1016/j.yqres.2013.05.004"},"issue":"2","journal":"Quaternary Research","pages":"167-179","pubRank":"1","pubYear":2013,"reportNumber":null,"title":"A ring-width-based reconstruction of June-July minimum temperatures since AD 1245 from white spruce stands in the Mackenzie Delta region, northwestern Canada","type":"publication","volume":"80"}],"reconstruction":"Y","scienceKeywords":["Air Temperature Reconstruction"],"site":[{"NOAASiteId":"56878","geo":{"geoType":"Feature","geometry":{"coordinates":["68.12","69.13","-135.52","-132.22"],"type":"POLYGON"},"properties":{"easternmostLongitude":"-132.22","maxElevationMeters":"5","minElevationMeters":"5","northernmostLatitude":"69.13","southernmostLatitude":"68.12","westernmostLongitude":"-135.52"}},"locationName":"Continent>North America>Canada>Northwest Territories","mappable":"N","paleoData":[{"NOAADataTableId":"31424","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>reconstructions>air temperature"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/northamerica/canada/mackenzie2013temp.txt","linkText":"Mackenzie Delta June-July Minimum Temperature Reconstruction ","urlDescription":"Data File","variables":[{"cvAdditionalInfo":null,"cvDataType":"CLIMATE RECONSTRUCTIONS|TREE RING","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"year Common Era","cvWhat":"age variable>age"},{"cvAdditionalInfo":"1 standard error = +/- 0.86 deg C; simple linear regression","cvDataType":"CLIMATE RECONSTRUCTIONS|TREE RING","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"reconstruction material>physical measurement>ring width","cvMethod":"regression analysis","cvSeasonality":"2-month period>Jun-Jul","cvShortName":null,"cvUnit":"degree Celsius","cvWhat":"earth system variable>temperature variable>minimum temperature>minimum surface temperature"},{"cvAdditionalInfo":"Environment Canada regional compilation of local instrumental records","cvDataType":"INSTRUMENTAL","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":"2-month period>Jun-Jul","cvShortName":null,"cvUnit":"degree Celsius","cvWhat":"earth system variable>temperature variable>minimum temperature>minimum surface temperature"},{"cvAdditionalInfo":"Regional divergence-free tree-ring chronology","cvDataType":"TREE RING","cvDetail":"composited","cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":null,"cvWhat":"statistical variable>proxy composite>tree ring standardized growth index"}]}],"dataTableName":"Mackenzie2013Temp","dataTableNotes":null,"earliestYear":1245,"earliestYearBP":705,"earliestYearCE":1245,"mostRecentYear":2007,"mostRecentYearBP":-57,"mostRecentYearCE":2007,"species":[],"timeUnit":"AD"}],"siteName":"Mackenzie Delta"}],"studyCode":null,"studyName":"Mackenzie Delta, NW Canada 750 Year Summer Temperature Reconstruction","studyNotes":"A ring-width-based reconstruction of Summer (June-July) minimum temperatures since AD 1245 from white spruce stands in the Mackenzie Delta region, northwestern Canada.","version":"1.0","xmlId":"18471"}