{"NOAAStudyId":"12912","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":"2012-05-17","dataPublisher":"NOAA","dataType":"SPELEOTHEMS","dataTypeInformation":"https://www.ncdc.noaa.gov/data-access/paleoclimatology-data/datasets/speleothem","difMetadataLink":"http://www1.ncdc.noaa.gov/pub/data/metadata/published/paleo/dif/xml/noaa-cave-12912.xml","doi":null,"earliestYearBP":12395,"earliestYearCE":-10445,"entryId":"noaa-cave-12912","funding":[],"investigators":"Berkelhammer, M.B.; Sinha, A.; Stott, L.D.; Cheng, H.; Pausata, F.; Yoshimura, K.","mostRecentYearBP":3653,"mostRecentYearCE":-1703,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/12912","originalSource":null,"publication":[{"abstract":"The emergence of high-resolution proxy records from the Asian Monsoon \r\nregion suggest that the monsoon system is bistable and can abruptly \r\ntransition between a suppressed and active state. This observation \r\nis critical in considering how the monsoon system may have influenced \r\nthe development of societies across South and East Asia during \r\nthe Holocene.  Using a new high-resolution (~5 years/sample) speleothem \r\nstable isotope record from Northeast India that spans the early and mid-\r\nHolocene, a number of abrupt changes in the oxygen isotopic composition \r\nof precipitation (d18O) are documented. The most dramatic of these \r\nevents occurred ~4,000 years ago when, over the course of approximately \r\na decade, isotopic values abruptly rose above any seen during the early \r\nto mid Holocene and remained at this anomalous state for almost two \r\ncenturies.  This event occurs nearly synchronously with climatic changes \r\ndocumented in a number of proxy records across North Africa, the Middle \r\nEast, the Tibetan Plateau, Southern Europe and perhaps as far as North \r\nAmerica. The changes in d18O were likely driven by a dynamic response \r\nof the Indian Summer Monsoon (ISM) to changes in surface heating on the \r\nTibetan Plateau and/or to large-scale ocean dynamics in the Indian Ocean \r\nBasin.  At this point, a quantitative characterization of the change in \r\nthe ISM is hindered by unconstrained aspects of the regional response \r\nof d18O to climate, but we hypothesize the excursion could represent \r\na shift towards an earlier monsoon withdrawal, a more northerly vapor \r\nsource region or a general decline in the total amount of monsoon \r\nprecipitation.  The new record provides a very significant advance \r\nwith respect to age control and sample resolution of terrestrial \r\nclimate change over South Asian during this period when a number \r\nof major societal changes occurred. While evidence of a causal \r\nrelationship between climate and the re-organization of the Indus \r\nValley and Old Kingdom Nile civilizations is beyond the scope of \r\nthis study, the tight age constraints of the record show with \r\na high degree of certainty that much of the documented de-urbanization \r\nof the Indus Valley at 3.9k yr BP occurred after multiple decades \r\nof a shift in the monsoon's character but before the monsoon returned \r\nto its previous mid-Holocene state. \r\n","author":{"name":"Berkelhammer, M., A. Sinha, L. Stott, H. Cheng, F. Pausata, and K. Yoshimura"},"citation":"M. Berkelhammer, A. Sinha, L. Stott, H. Cheng, F.S.R. Pausata, K. Yoshimura (2012) An Abrupt Shift in the Indian Monsoon 4000 Years Ago. In: Climates, Landscapes and Civilization, Eds: Liviu Giosan, Dorian Q. Fuller, Kathleen Nicoll, Rowan K. Flad, Peter D. Clift. DOI: 10.1029/2012GM001207.","edition":null,"identifier":{"id":"10.1029/2012GM001207","type":"doi","url":"http://dx.doi.org/10.1029/2012GM001207"},"issue":null,"journal":"Geophysical Monograph Series","pages":null,"pubRank":"1","pubYear":2012,"reportNumber":null,"title":"An Abrupt shift in the Indian Monsoon 4,000 years ago","type":"publication","volume":null}],"reconstruction":"N","scienceKeywords":["Monsoon"],"site":[{"NOAASiteId":"53045","geo":{"geoType":"Feature","geometry":{"coordinates":["25.2622","91.8167"],"type":"POINT"},"properties":{"easternmostLongitude":"91.8167","maxElevationMeters":"1290","minElevationMeters":"1290","northernmostLatitude":"25.2622","southernmostLatitude":"25.2622","westernmostLongitude":"91.8167"}},"locationName":"Continent>Asia>Southcentral Asia>India","mappable":"Y","paleoData":[{"NOAADataTableId":"21255","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>speleothems>oxygen isotopes"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/asia/india/mawmluh2012.txt","linkText":"mawmluh2012.txt","urlDescription":"Speleothem","variables":[{"cvAdditionalInfo":null,"cvDataType":"SPELEOTHEMS","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"calendar year before present","cvWhat":"age variable>age"},{"cvAdditionalInfo":null,"cvDataType":"SPELEOTHEMS","cvDetail":"raw","cvError":null,"cvFormat":"Numeric","cvMaterial":"geological material>identified mineral>carbonate>calcium carbonate","cvMethod":"isotope ratio mass spectrometry","cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil VPDB","cvWhat":"chemical composition>isotope>isotope ratio>delta 18O"}]},{"NOAAKeywords":["earth science>paleoclimate>speleothems>oxygen isotopes"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/asia/india/mawmluh2012.xls","linkText":"mawmluh2012.xls","urlDescription":"Speleothem","variables":[]}],"dataTableName":"KM-A","dataTableNotes":null,"earliestYear":12395,"earliestYearBP":12395,"earliestYearCE":-10445,"mostRecentYear":3653,"mostRecentYearBP":3653,"mostRecentYearCE":-1703,"species":[],"timeUnit":"cal yr BP"}],"siteName":"Mawmluh Cave"}],"studyCode":null,"studyName":"Mawmluh Cave, India Holocene Stalagmite d18O Data","studyNotes":"d18O from a calcitic stalagmite (KM-A) from Mawmluh Cave, \nlocated in Cherrapunji, Meghalaya in northeast India. \nDating is based on 8 U/Th series dates, which are described \nin the publication text. \n\nMawmluh Cave, India: \n25°15'44\"N, 91°52'54\"E, 1290m elevation. \n","version":"1.0","xmlId":"10978"}