The History of the Monsoon in Southern Arabia: Results Based on Stable Isotopes and U/Th Dating of Speleothems

Abstract

Studies of marine sediments have shown that the intensity of the Indian Ocean monsoon system has varied greatly over the past several glacial-interglacial cycles in response to changes in Northern Hemisphere insolation in the precession band and/or to glacial boundary conditions (e.g. Sirocko et al., 1993; Overpeck et al., 1996). Less well known is how marine indicators of increased monsoon intensity relate to climate variation of continental areas around the Indian Ocean, particularly the Arabian Peninsula. Here we present a palaeoclimate record extending back to 125 ka from northern Oman based on U-Th dating and stable isotope analyses of speleothems. The aims of this study are to provide further information on the timing and intensity of monsoonal rainfall on the Arabian Peninsula, to extend the palaeoclimate record further back in time, and to investigate how continental climate variation compares to marine records of monsoon variation from the nearby Arabian Sea.