THE INTERACTION BETWEEN CLIMATE AND EROSION IN HIGH ALTITUDE MOUNTAIN ENVIRONMENTS: THE AFFECT OF PRECIPITATION GRADIENTS UPON HEADWALL EROSION IN NORTHERN INDIA, NW HIMALAYA

The interaction between tectonics, erosion and climate is integral to defining rates and styles of landscape evolution within high altitude mountain belts. Although compelling evidence suggests that long-term erosion rates are primarily governed by spatiotemporal variations in precipitation, few studies have systematically tested this hypothesis along a precipitation gradient within the Himalayan-Tibetan orogen. Critically there is an absence of substantiated research focused upon landscape change with respect to climate within the upper extent of glaciated catchments. More specifically, the strength of coupling between precipitation and erosional headwall processes in the NW Himalayas is unknown. The aim of this project is therefore to determine the affect of the steep S-N precipitation gradient upon rates of glacial headwall erosion in northern India. To accomplish this, I am applying cosmogenic nuclide dating (TCN) to supraglacial debris collected from 10 glaciated catchments between the warm, wet conditions of the Greater Himalayan Range in the south and the hyper-arid environment of the Transhimalaya in the north. The TCN concentration in the supraglacial debris collected from each of these catchments will be directly proportional to the duration of rock exposure to cosmic rays and inversely proportional to the rate of glacial headwall erosion. My primary hypothesis is that if glacial headwall erosion is related to precipitation magnitude, the headwall erosion rates will be greater in the wetter regions of the Himalaya. The erosion dataset generated from this project could compliment other projects as a measure of landscape change; future research into sediment transfer, mass displacements, avalanching and paraglacial and periglacial processes within the upper extents of glaciated catchments. This project will help to address present questions related to the control of environmental and climatic conditions upon landscape evolution and surface processes within high altitude, active mountain belts.