New Zealand South Island 30KYr Speleothem Stable Isotope Data Williams, P.W.; Neil, H.L.; Zhao, J.-x. Williams, P.W. Neil, H.L. Zhao, J.-x. Last Glacial Maximum earth science/paleoclimate/speleothems (delta 18O,calcium carbonate,null,per mil PDB,null,speleothems,corrected,isotope ratio mass spectrometry,N,corrected for ice volume) 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 (NWSI north-west of the South Island>LATITUDE -42>LONGITUDE 172) The occurrence of speleothems in New Zealand with reversed magnetism indicates that secondary calcite deposition in caves has occurred for more than 780 thousand years (ka). 394 uranium-series dates on 148 speleothems show that such deposition has taken place somewhere in the country with little interruption for more than 500 ka. A relative probability distribution of speleothem ages indicates that most growth occurred in mild, moist interglacial and interstadial intervals, a conclusion reinforced by comparing peaks and troughs in the distribution with time series curves of speleothem d18O and d13C values. The stable isotope time series were constructed using data from 15 speleothems from two different regions of the country. The greater the number of overlapping speleothem series (i.e. the greater the sample depth) for any one region, the more confidence is justified in considering the stacked record to be representative of the region. Revising and extending earlier work, composite records are produced for central-west North Island (CWNI) and north-west South Island (NWSI). Both demonstrate that over the last 15 ka the regions responded similarly to global climatic events, but that the North Island site was also influenced by the waxing and waning of regional subtropical marine influences that penetrated from the north but did not reach the higher latitudes of the South Island. Cooling marking the commencement of the last glacial maximum (LGM) was evident from about 28 ka. There was a mid-LGM interstadial at 23-21.7 ka and Termination 1 occurred around 18.1 ka. The glacial-interglacial transition was marked by a series of negative excursions in d18O that coincide with dated recessional moraines in South Island glaciers. A late glacial cooling event, the NZ Late Glacial Reversal, occurred from 13.4-11.2 ka and this was followed by an early Holocene optimum at 10.8 ka. Comparison of d18O records from NWSI and EPICA DML ice-core shows climatic events in New Zealand to lag those in Antarctica by several centuries to a thousand years. Waxing and waning of subantarctic and subtropical oceanic influences in the Tasman Sea are considered the immediate drivers of palaeoclimatic change. STUDY NOTES: Composite speleothem d18O and d13C data for north-west South Island, New Zealand. d18O data are ice volume corrected (ivc) assuming 1.2 per mil correction at 20 ka. The original data were published in Williams et al. (2005) and were based on 8 speleothems with 43 TIMS dates. The new record is constructed from the same 8 speleothems but has 56 dates and 641 stable isotope data points, and extends from 500 - 30 000 years BP. Northwest South Island ~42°S, 172°E. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Williams, P.W. Investigator : Neil, H.L. Investigator : Zhao, J.-x. 2010-07-22 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/9792 https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/pacific/south-island2010.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/pacific/south-island2010.xls https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/pacific/south-island2010.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/pacific/south-island2010.xls English https://www.ncdc.noaa.gov/paleo/study/9792 https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/pacific/south-island2010.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/pacific/south-island2010.xls Williams, P.W., H. Neil, and J.-X. Zhao. 2010. Age frequency distribution and revised stable isotope curves for New Zealand speleothems: palaeoclimatic implications. International Journal of Speleology, 39(2), 99-112. Bologna (Italy). ISSN 0392-6672. START YEAR: 29876 cal yr BP * END YEAR: 508 cal yr BP 172 -42 172 -42