{"NOAAStudyId":"24979","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":"2018-08-14","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-24979.xml","doi":null,"earliestYearBP":null,"earliestYearCE":null,"entryId":"noaa-cave-24979","funding":[],"investigators":"Polk, J.S.; van Beynen, P.E.; Asmerom, Y.; Polyak, V.J.","mostRecentYearBP":null,"mostRecentYearCE":null,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/24979","originalSource":null,"publication":[{"abstract":"Little is known about the potential of organic substances found within cave sediments to provide useful reconstructions of past climatic changes. Here, we present a study of the carbon isotopes of fulvic acids extracted from sediments from a cave in west-central Florida. Fulvic acids are the most contemporaneous representation of soil humic substances derived from vegetation growing above the cave. Radiocarbon dating of these sediments constrains their depositional period to be late-Holocene. The range of the fulvic acid δ13C record shows the dominance of C3 vegetation during this period, but with changes in abundance and the shifting presence of C4 plants. The δ13C values record both the Little Ice Age and Medieval Climate Anomaly which produce drier and wetter conditions for Florida, respectively. Our conclusion that the stable carbon isotopic values of the cave sediment record as a proxy for vegetation change as driven by variability in precipitation is strongly supported by a comparison with the δ13C and δ18O values of two uranium-series dated speleothems from this part of Florida, with both being proxies for precipitation change.","author":{"name":"Polk, J.S., P. van Beynen, Y. Asmerom, and V.J. Polyak"},"citation":"Polk, J.S., P. van Beynen, Y. Asmerom, and V.J. Polyak. 2013. Reconstructing past climates using carbon isotopes from fulvic acids in cave sediments. Chemical Geology, 360-361, 1-9. doi: 10.1016/j.chemgeo.2013.09.022","edition":null,"identifier":{"id":"10.1016/j.chemgeo.2013.09.022","type":"doi","url":"http://dx.doi.org/10.1016/j.chemgeo.2013.09.022"},"issue":null,"journal":"Chemical Geology","pages":"1-9","pubRank":"1","pubYear":2013,"reportNumber":null,"title":"Reconstructing past climates using carbon isotopes from fulvic acids in cave sediments","type":"publication","volume":"360-361"}],"reconstruction":"N","scienceKeywords":null,"site":[{"NOAASiteId":"57700","geo":{"geoType":"Feature","geometry":{"coordinates":["29.15827","-82.3519"],"type":"POINT"},"properties":{"easternmostLongitude":"-82.3519","maxElevationMeters":"34","minElevationMeters":"34","northernmostLatitude":"29.15827","southernmostLatitude":"29.15827","westernmostLongitude":"-82.3519"}},"locationName":"Continent>North America>United States Of America>Florida","mappable":"Y","paleoData":[{"NOAADataTableId":"36782","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>speleothems>carbon isotopes"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/northamerica/usa/florida/polk2013/polk2013-jennings.txt","linkText":"Jennings Cave d13C Data","urlDescription":"NOAA Template File","variables":[{"cvAdditionalInfo":"composite sediment depth","cvDataType":"SPELEOTHEMS","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"centimeter","cvWhat":"depth variable>depth"},{"cvAdditionalInfo":null,"cvDataType":"SPELEOTHEMS","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":"reconstruction material>organic compound index>fulvic acid","cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"per mil VPDB","cvWhat":"chemical composition>isotope>isotope ratio>delta 13C"}]}],"dataTableName":"JenningsCave_Florida_USA_d13C Polk2013","dataTableNotes":"Contributed to NOAA Paleoclimatology as part of Rodysill 2018 synthesis study.","earliestYear":null,"earliestYearBP":null,"earliestYearCE":null,"mostRecentYear":null,"mostRecentYearBP":null,"mostRecentYearCE":null,"species":[],"timeUnit":null}],"siteName":"Jennings Cave, Florida"}],"studyCode":null,"studyName":"Jennings Cave, Florida, USA d13C cave sediment Data from -984 to 2007 CE","studyNotes":"Contributed to NOAA Paleoclimatology as part of Rodysill et al. 2018 synthesis study.","version":"1.0","xmlId":"23114"}