Almost one third of the world’s population depends on water supplied from rivers originating in the Tibetan Plateau, i.e., mainly monsoonal precipitation. Therefore, how the Asian Monsoon system will develop in the future has socio-economic significance. It is essential to refine future climate change scenarios (e.g., IPCC) and the consequences of a changing climate for ecosystems and human societies by validation against improved knowledge of the timing, duration and intensity of past climatic variability and environmental impact on long geologic time scales and under different boundary conditions. Nam Co, one of the largest and deepest lakes on the Tibetan Plateau, records the temporal development of large-scale atmospheric circulation systems due to its location in the modern monsoon regime. Comprehensive pre-site survey seismic data clearly show an infill of >700 m of well-layered, undisturbed sediments in the central part of the lake, spanning several glacial/interglacial cycles. Short piston-core sediment accumulation rates for the past 24 ka and seismostratigraphic investigations suggest a lake formation of >1 Ma. Nam Co's sedimentary record is an exemplary archive to fill the paleoclimate data gap between two ICDP/IODP transects that will allow comparisons of climate evolution/behavior on a continental scale. Continuous, high-resolution Nam Co paleoenvironmental records for these long time scales will further allow the study of sediment budget changes under varying climatic and tectonic settings and contribute to a better understanding of the Quaternary geomagnetic field, since capturing rates of change and defining dynamic features can only be preserved in the highest resolution records. The high altitude Tibetan Plateau also is unique as it has a high degree of endemism in aquatic organisms that are dependent on persistent water bodies; Nam Co likely served as a dispersal centre, because most other lakes desiccated during dry glacial periods. Therefore, Nam Co is a first-class site to study the links between climate and biological evolution within isolated Tibetan Plateau ecosystems. These studies will also include the unknown geomicrobiological communities and processes in the high altitude lacustrine deep biosphere.

Leading PI: Dr. Torsten Haberzettl (University of Greifswald, Germany).