Mt. Arthur, New Zealand 31KYr Speleothem Stable Isotope Data Hellstrom, J.C.; McCulloch, M.T.; Stone, J.O. Hellstrom, J.C. McCulloch, M.T. Stone, J.O. earth science/paleoclimate/speleothems (depth,null,null,millimeter,null,speleothems,null,null,N,null) earth science/paleoclimate/speleothems (age,null,null,calendar year before present,null,speleothems,null,null,N,null) earth science/paleoclimate/speleothems (delta 13C,calcium carbonate,null,per mil PDB,null,speleothems,raw,isotope ratio mass spectrometry,N,null) earth science/paleoclimate/speleothems (delta 18O,calcium carbonate,null,per mil PDB,null,speleothems,raw,isotope ratio mass spectrometry,N,null) earth science/paleoclimate/speleothems earth science/paleoclimate/speleothems (Nettlebed Cave>LATITUDE -41.25>LONGITUDE 172.6833) Uranium-series dating and stable isotope analyses of two speleothems from northwest Nelson, New Zealand, record changes in regional climate and local forest extent over the past 31,000 years. Oxygen isotope variation in these speleothems primarily represents changes in the meteoric waters falling above the caves, possibly responding to latitudinal changes in the position of the Subtropical Front in the Tasman Sea. Seven positive excursions can be identified in the oxygen isotope record, which coincide with periods of glacier advance, known to be sensitive to northward movement of the Subtropical Front. Four glacier advances occurred during oxygen isotope stage 2, with the most extreme glacial conditions centered on 19,000 cal yr B.P. An excursion in the oxygen isotope record from 13,800 to 11,700 cal yr B.P. provides support for a previously identified New Zealand glacier advance at the time of the Younger Dryas Stade, but suggests it began slightly before the Younger Dryas as recorded in Greenland ice cores. Carbon isotope variations in the speleothems record changes in forest productivity, closely matching existing paleovegetation records. On the basis of vegetation changes, stage 2 glacial climate conditions terminated abruptly in central New Zealand, from 15,700 to 14,200 cal yr B.P. Evidence of continuous speleothem growth at one site suggests that depression of the local treeline was limited to 600-700 m below its present altitude, throughout the last 31,000 years. STUDY NOTES: Continuous high-resolution stable isotope records from caves in New Zealand over the last 31,000 yr. Mt. Arthur (1795 m) is located northwestern corner of New Zealand's South Island, underlain by many known cave systems, the two largest and deepest being Exhaleair and Nettlebed Caves used for this study. A 50-mm-diameter core sample was recovered from each site by drilling into gently sloping flowstones (massive sheet speleothems which form on cave walls and floors). Core MD3 was dated at nine points, and Core ED1 was dated at three points, using the mass-spectrometric 238U-234U-230Th method. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Hellstrom, J.C. Investigator : McCulloch, M.T. Investigator : Stone, J.O. 2010-09-30 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/10441 https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/pacific/mt-arthur1998.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/pacific/mt-arthur1998.xls https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/pacific/mt-arthur1998.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/pacific/mt-arthur1998.xls English https://www.ncdc.noaa.gov/paleo/study/10441 https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/pacific/mt-arthur1998.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/pacific/mt-arthur1998.xls Hellstrom, J., M. McCulloch, and J. Stone. 1998. A detailed 31,000-year record of climate and vegetation change, from the isotope geochemistry of two New Zealand speleothems. Quaternary Research, Vol. 50, pp. 167-178. ARTICLE NO. QR981991 START YEAR: 31271 cal yr BP * END YEAR: 128 cal yr BP 172.6833 -41.25 172.6833 -41.25