Southwest Australian speleothem records – an update

Abstract

Southwest Western Australia (SWWA) experienced a clear climatic change during the late 20thC and has been identified as highly vulnerable to future climate change (Hope et al., 2010). Paleoclimate records could assist in understanding SWWA climate but very few exist for this region. Early investigations into speleothems were very promising, demonstrating that speleothem-based proxies record the multidecadal reduction in rainfall since the 1970s (Treble et al., 2003, 2005; Fischer and Treble, 2008). Subsequent efforts to build a paleoclimate record revealed that the climate-speleothem signal was poorly understood in our studied cave e.g. disagreement between coeval records; non-linear response in the speleothem-climate signal. To address this, a cave monitoring program was launched in 2005 involving instrumentation of Golgotha Cave and monthly drip water collection. We present a summary of these findings during 2005-2013 from two contrasting high and low-flow drip sites, as well as our progress on building a high-resolution climate record spanning the last ~600 years