noaa-cave-20612 Brown's Cave, Florida Mid-Holocene Speleothem Stable Isotope Data Pollock, A.L.; van Beynen, P.E.; DeLong, K.L.; Polyak, V.J.; Asmerom, Y. Brown's Cave, Florida Mid-Holocene Speleothem Stable Isotope Data 2016-10-14 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/20612 Investigator A.L. Pollock Investigator P.E. van Beynen Investigator K.L. DeLong Investigator V.J. Polyak Investigator Y. Asmerom earth science paleoclimate speleothems depth,null,null,millimeter,null,speleothems,null,null,N,null earth science paleoclimate speleothems delta 18O,calcium carbonate,null,per mil VPDB,null,speleothems,raw,isotope ratio mass spectrometry,N,null earth science paleoclimate speleothems delta 13C,calcium carbonate,null,per mil VPDB,null,speleothems,raw,isotope ratio mass spectrometry,N,null earth science paleoclimate speleothems age,null,null,calendar year before present,null,speleothems,null,null,N,Distance from top of speleothem earth science paleoclimate speleothems carbon isotopes earth science paleoclimate speleothems oxygen isotopes geoscientificInformation 6603 cal yr BP 4626 cal yr BP Complete 28.8894 28.8894 -82.5186 -82.5186 Continent North America United States Of America Florida Brown's Cave>LATITUDE 28.8894>LONGITUDE -82.5186 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 Pollock, A.L., P.E. van Beynen, K.L. DeLong, V. Polyak and Y. Asmerom 2017 The Holocene

The mid-Holocene is a period of warmer temperatures relative to those for most of this current interglacial. It possessed a weak latitudinal temperature gradient which is similar to what is expected in the coming decades. A changing gradient will impact climate teleconnections that have a significant effect on precipitation variability. Our window into the mid-Holocene climate is a high resolution (near-annual) stalagmite stable isotope-based paleoprecipitation record from Brown's Cave in West-Central Florida. An oxygen isotope (d18O) time-series tied to a uranium-series (U-series) chronology covers a 2,000-year period from 6.6 to 4.6 ka. To test the hypothesis of future drier climate, we compared our reconstruction to another speleothem derived precipitation record from our study area that spans the last 1,600 years. The comparison showed that the mid-Holocene was drier than the last 1.5 millennia. We posit the cause of this aridity was a westward expansion of the North Atlantic Subtropical High (NASH) coupled with changes in the planetary boundary layer in the Gulf of Mexico. Time series analysis of our oxygen isotopic record found little evidence of any teleconnections originating from the North Atlantic. We found no periodicity matching the North Atlantic Oscillation during the mid-Holocene. However, there is some indication of a weak, quasi-persistent oscillation within the temporal periodicity of the Atlantic Multidecadal Variability. STUDY NOTES: Speleothem stable isotope (d13C and d18O) data from stalagmite BC01-07 collected in Brown's cave, central Florida, for the mid-Holocene (6.6 - 4.6 KYrBP)

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/northamerica/usa/florida/browns2017iso.txt Data File; Brown's Cave Mid-Holocene Stable Isotope Data USA/NOAA DIF Version 9.8.4 2018-12-11 2018-12-11