Seasonality and variations in moisture-supply on different timescales (1-104 yrs) and their relation to surface processes in the NW Himalaya

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One of the outstanding questions in (paleo)climate research in the Himalaya and the adjacent mountainous areas in Central Asia concerns seasonality and the source of moisture. In this context, we intend to study in detail two of the dominant landscape-shaping processes generally associated with seasonal moisture supply: (1) glacial erosion and deposition, which are highly sensitive to spatiotemporal trends in moisture transport, and (2) landslides and associated processes that control hillslope decay. This proposal will analyze geomorphic processes on 1 to 104 yrs timescales and on 102 to 1010 m2 spatial scales. First, we strive to understand the present¬day synoptic moisture characteristics and their relation to local topography. We will use remotely-sensed rainfall and snow-cover data combined with field measurements of glacial velocities and snow depths on a weekly to annual basis. This will be complemented by field observation and change-detection techniques from satelliteimagery time series of the last 4 decades to identify and quantify landscape changes from hillslope to river-basin scales along the climatic gradient of the Himalaya. Second, we will use cosmogenic nuclide dating and geomorphic analysis to construct a detailed chronology of glacial and hillslope processes in a key region of the NW Himalaya that lies in the transition between the main moisture sources. This will allow deciphering the relative influence of erosive processes during climatic oscillations in the Indian Monsoon system. Overall, we expect to provide much needed data on the hydrologic budget of the Himalaya and the provenance of eroded sediments.