Microfossils as indicators of aquatic ecosystem evolution and monsoon dynamics

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During the 2nd funding period (12 months) we propose to (1) perform coupled actualisticecological and taxonomic analysis of Recent ostracodes from the Tibetan Plateau (TP), to use species assemblages and shell chemistry to detect lake level changes in response to monsoon dynamics, melt water supply and variations in precipitation vs. evaporation ratios at (2) annual to decadal resolution for the past approx. 1000 years from Lakes Mug Co, Ra’og Co and Tangra Yum Co located along an East-West transect ranging from approx. 101°E to 86°E, and at (3) decadal to centennial resolution from Lakes Tangra Yum Co and Heihai to assess longterm environmental changes and short-term events during the late Pleistocene and Holocene. Lake sites are strategically selected on the southern and northern TP in order to detect different monsoonal air mass impact. The environmental interpretation of fossil ostracode assemblages will be based on ecological tolerances, preferences and transfer functions. The proxy data-inferred regional hydrological effects of monsoon development will be compared to results from statistical downscaling at selected sites for the last 7000 years. GCM simulations forced with different combinations of external forcing parameters (orbital, solar, volcanic, greenhouse gases) will be used to decipher climatic drivers of Holocene monsoon dynamics.