Online seminar by Elizabeth Patterson from William Paterson University
21 February 2025
KST 09:00
Abstract:
Speleothems are robust hydroclimate archives, but most proxies are qualitative (eg, “wetter” or “drier”), limiting their effectiveness for quantitative comparisons with climate models. Here, I use δ⁴⁴Ca and Mg/Ca—emerging proxies for rainfall amount—to generate semi-quantitative rainfall reconstructions from a stalagmite in central Vietnam (45–4 ka). Our reconstructions indicate a ~50% reduction in rainfall during the Last Glacial Maximum (21 ka), primarily driven by decreased autumn monsoon precipitation due to sea-level lowstand conditions. PMIP4-CMIP6 climate models also simulate Last Glacial Maximum drying in central Vietnam but substantially underestimate annual rainfall change due to a summer precipitation bias (model mean = 7% drier). However, simulated autumn rainfall better aligns with speleothem proxies (model mean = 29% drier), suggesting that models broadly capture changes in autumn monsoon rainfall. Ultimately, our findings further demonstrate the potential of δ⁴⁴Ca and Mg/Ca as quantitative rainfall proxies and highlight their utility in validating climate model simulations of rainfall amount.
Publications: https://sites.google.com/view/elizabethpattersonphd/publications?authuser=0
Zoom link:
https://pusan.zoom.us/j/83924031855?pwd=OqUaXRDRdHUELCJNhwvWrdDLSAek4Z.1
Meeting ID: 839 2403 1855
Passcode: 712616