München 2019 – wissenschaftliches Programm
UP 9.4: Vortrag
Donnerstag, 21. März 2019, 15:20–15:40, HS 22
Testing the variability of speleothem growth in Glacial versus Interglacial climate — •Carla Roesch and Kira Rehfeld — Institute of Environmental Physics, Ruprecht-Karls-University Heidelberg, Germany
Major changes in global mean climate occurred since the Last Glacial Maximum (21 kyr ago), with a 3-8∘C warming of global mean temperature, an about 120m rise in sea level and an increase of about 100ppm in CO2. On long timescales, new evidence shows that surface temperature variability decreased globally. However, signs and magnitudes are still poorly constrained for precipitation.
Variations in growth rates of speleothems (cave deposits) have been suggested as an indicator of such global environmental changes. To further investigate the dynamics and variability of paleoclimate we investigate changes in speleothem growth rates. These are derived by modeling the accumulation process based on Uranium/Thorium radiometric point estimates of the age at different depths within the archive. The Bayesian models we apply draw accumulation rates from a Gamma-distribution.
We compare our results to reconstructions from other age-depth models to test the possibility of changing growth rates from the last Glacial to our current Interglacial.