Eight centuries of hydroclimatic variability recorded in a southwest Australian speleothem with an annually resolved chronology — Australian Meteorological and Oceanographic Society
  1. Schedule
  2. Afternoon Tea + Poster Session 1
  3. Eight centuries of hydroclimatic variability recorded in a southwest Australian speleothem with an annually resolved chronology

Eight centuries of hydroclimatic variability recorded in a southwest Australian speleothem with an annually resolved chronology (#1045)

Pauline Treble 1 2 , Nerilie Abram 3 , Andy Baker 2 , Alan Griffiths 1 , John Hellstrom 4 , Petra Bajo 1 4 5 , Andrea Borsato 6 , David Paterson 7
  1. ANSTO, Lucas Heights, NSW, Australia
  2. UNSW Sydney, Kensington, NSW, Australia
  3. Australian National University, Acton, ACT, Australia
  4. University of Melbourne, Parkville, VIC, Australia
  5. Croatian Geological Survey, Zagreb, Croatia
  6. University of Newcastle, Callaghan, NSW, Australia
  7. Australian Synchrotron ANSTO, Clayton, VIC, Australia

Speleothems from Golgotha Cave in south west Western Australia have been investigated to extend our knowledge of past climate variability for this region during the last millennium. A challenge in their interpretation has been the disagreement between these records despite representing coeval growth from within the same cave. This presentation will focus on a record (GL-S4) that grew continuously over the past eight centuries determined by counting annual chemical laminations. The paleoclimate interpretation of the GL-S4 record is informed by long-term monitoring of Golgotha Cave to characterise the hydrology1-5, hydrochemistry5,6, rainfall water isotopes7 and the development of proxy system forward models1,8. A principal components analysis demonstrates that the dominant variability in the GL-S4 record is attributable to hydroclimate (PC 1), soil connectivity (PC 2) and bedrock weathering (PC 3). These results provide eight centuries of baseline data to extend our knowledge of past hydroclimate variability for this region that is currently experiencing a prolonged decrease in rainfall.

  1. Treble, P.C., et al. (2013), An isotopic and modelling study of flow paths and storage in Quaternary calcarenite, SW Australia: implications for speleothem paleoclimate records, Quat. Sci. Rev., 64, 90-103.
  2. Mahmud, K., et al. (2015), Terrestrial LiDAR Survey and Morphological Analysis to Identify Infiltration Properties in the Tamala Limestone, Western Australia, IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 8, 4871-4881.
  3. Mahmud, K., et al. (2016), Estimation of deep infiltration in unsaturated limestone environments using cave lidar and drip count data, Hydrol. Earth Syst. Sci., 20, 359-373.
  4. Mahmud, K., et al. (2018), Hydrological characterization of cave drip waters in a porous limestone: Golgotha Cave, Western Australia, Hydrol. Earth Syst. Sci., 22, 977-988.
  5. Treble, P.C., et al. (2015), Impacts of cave air ventilation and in-cave prior calcite precipitation on Golgotha Cave dripwater chemistry, southwest Australia, Quat. Sci. Rev., 127, 61-72.
  6. Treble, P.C., et al. (2016), Roles of forest bioproductivity, transpiration and fire in a nine-year record of cave dripwater chemistry from southwest Australia, Geochim. Cosmochim. Acta, 184, 132-150.
  7. Griffiths et al. (in prep.), A decade of precipitation stable water isotope variability in coastal southwestern Western Australia.
  8. Treble, P.C., et al. (2019), Separating isotopic impacts of karst and in-cave processes from climate variability using an integrated speleothem isotope-enabled forward model, EarthArXIV 10.31223/osf.io/j4kn6.
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