Thursday, March 21, 2013, 4:30PM - 5:30PM
Full title: Opportunities, limitations, and challenges of hydrochemistry-based melt modelling in high alpine catchments
Abstract: The hydrologic regimes of High Asian catchments are presently not well understood. Much progress has been made in recent years to monitor the changing state of glaciers, including in the Himalayan region of High Asia. While remote sensing is useful for modelling the behavior of ice and snow cover over vast stretches of remote regions, there are numerous uncertainties in translating this information to river discharge values. At the catchment scale the use of isotopes and conservative tracers allow for hydrochemistry-based hydrograph separation as a different approach to quantifying contributions of ice and snow melt to river discharge, as well as contributions from rain and groundwater storage.
Results presented here are from 2012 field work in the Langtang and Khumbu Valleys of Nepal. While preliminary estimates of cryospheric melt contributions to discharge can be made, data from the first field season highlight the spatiotemporal variability of chemistry results and are useful for guiding future field efforts. The end goal of the melt modelling is to evaluate vulnerability of water resources to the impacts of climate change. In order for people to adapt to those changes, it is first necessary to understand where water comes from. This work is conducted as part of the USAID-funded collaborative project Contributions to High Asian Runoff from Ice and Snow (CHARIS).