HR: 11:50h
AN: U42A-07    [Abstracts]
TI: Holocene Sun-Monsoon Linkage Recorded in Stalagmites From Oman
AU: Mangini, A
EM: augusto.mangini@iuo.uni-heidelberg.de
AF: Heidelberg Academy of Sciences, Im Neuenheimer Feld 229, Heidelberg, 69120 Germany
AU: * Fleitmann, D
EM: fleitman@pangea.stanford.edu
AF: Department of Geological and Environmental Sciences, Stanford University, 325 Braun Hall, Stanford, CA 94305-2115 United States
AU: Neff, U
EM: uli.neff@iup.uni-heidelberg.de
AF: Heidelberg Academy of Sciences, Im Neuenheimer Feld 229, Heidelberg, 69120 Germany
AU: Burns, S J
EM: sburns@geo.umass.edu
AF: Department of Geosciences, University of Massachusetts, Morrill Science Center,, Amherst, MA 01002 United States
AU: Mudelsee, M
EM: mudelsee@rz.uni-leipzig.de
AF: Institute of Meteorology, University of Leipzig, Stephanstrasse 3, Leipzig, 04103 Germany
AU: Kramers, J
EM: kramers@geo.unibe.ch
AF: Institute of Geological Sciences, University of Bern, Baltzerstrasse 1-3, Bern, 3012 Switzerland
AU: Matter, A
EM: albert.matter@geo.unibe.ch
AF: Institute of Geological Sciences, University of Bern, Baltzerstrasse 1-3, Bern, 3012 Switzerland
AB: In order to reveal a possible sun-climate connection well-dated and highly resolved climate records from key-localities are necessary. Such records can be gained from Uranium-series dated stalagmites from Oman, where climate is still strongly influenced by the Indian monsoon. Two high-resolution oxygen isotope profiles derived from Th-U-dated stalagmites from Hoti Cave ($23\deg$05N, $57\deg$21E; 800 masl) in Northern Oman and Qunf Cave ($17\deg$10N, $54\deg$18E; 650 masl) continuously cover the period between 10.1 and 6.2 kyr B.P. and 10.5 and 2.7 kyr B.P respectively. The temporal resolution of these oxygen isotope profiles averages 4 and 5 years for stalagmites H5 (Hoti Cave) and Q5 (Qunf Cave) respectively. We assume that oxygen isotope ratios (\delta$^{18}$O) of stalagmite calcite primarily reflect variations in the amount of monsoon rainfall (the so-called "amount effect"), with more negative \delta$^{18}$O values reflecting higher monsoon rainfall due to changes in monsoon intensity and/or convective activity within the ITCZ. The high temporal resolution of both speleothem \delta$^{18}$O records enables a precise comparison with atmospheric \Delta$^{14}$C measured in tree-rings. The similarity between the \delta$^{18}$O and \Delta$^{14}$C time series at multi-decadal timescales, both in their general pattern and in the number of peaks, suggests that higher monsoon rainfall in Oman coincides with higher solar activity and vice versa. Because much of the variation in \Delta$^{14}$C at these timescales is attributed to solar forcing through variations in solar activity, the data reveal a possible close sun-monsoon connection.
DE: 9320 Asia
DE: 3344 Paleoclimatology
DE: 1854 Precipitation (3354)
DE: 1045 Low-temperature geochemistry
DE: 1650 Solar variability
SC: Union [U]
MN: 2004 AGU Fall Meeting