Recontructing East Asian monsoon climate history between 12.5 and 7 Ma: Linkages to tectonic events, cryosphere evolution and orbital forcing

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The Middle to Late Miocene climate transition towards modern boundary conditions is stillpoorly resolved, mainly due to the scarcity of continuous, well-dated climate archives. Wepropose to reconstruct East Asian climate variability and investigate monsoonal evolution inresponse to tectonic events, cryosphere evolution and orbital forcing over the Mioceneinterval 12.5 -7 Ma. Our primary targets are: 1) to develop a high-resolution, orbitally-tunedchronology in South China Sea ODP Site 1146, where an expanded, continuous carbonaterichsedimentary succession was recovered and 2) to provide a synthesis of climate andocean chemistry proxies (principally benthic and planktic δ18O, δ13C supplemented by Mg/Ca,carbonate dissolution indices and faunal census counts) that will focus on the temporalevolution of surface and bottom water masses. We will target phases of major climaticchange such as the Late Miocene ice growth events (Mi5-Mi7 of Miller et al., 1991) and theinferred change in monsoon intensity at ~ 8 Ma associated with Himalayan uplift. This workwill supply an essential chronological framework for the South China Sea, and provide ahigh-resolution multiproxy investigation of East Asian climate and monsoon variability.