Differentiating between rain,snow, and glacier contributions to river discharge in the western Himalaya using remote-sensing data and distributed hydrological modeling |
| |
| Institution: | 1. Department of Earth and Environmental Science, Potsdam University, Germany;2. Department of Geography, University of California, Santa Barbara, USA;3. Earth Surface Geochemistry, Helmholtz Centre Potsdam, GFZ German Research Center for Geosciences, Telegrafenberg, 14473 Potsdam, Germany;4. Institute of Geological Sciences, Freie Universität Berlin, 12249 Berlin, Germany;1. College of Engineering, Peking University, Beijing 100871, PR China;2. Institute of Water Sciences, Peking University, Beijing 100871, PR China;1. Laboratoire Hydrosciences — UMR 5569 (CNRS, IRD, Montpellier University 1&2), CC57, Université Montpellier 2 Sciences et Techniques, Place Eugène Bataillon, 34095 Montpellier Cedex 5, France;2. Department of Environmental Sciences, COMSATS Institute of Information Technology, 22060 Abbottabad, Pakistan;3. Institute of Earth Surface Dynamics, Faculty of Geosciences and Environment, University of Lausanne, Switzerland;4. Laboratoire des Transferts en Hydrologie et Environnement — UMR 5564 (CNRS, IRD), Université Joseph Fourrier, Grenoble INP), LGGE, 54 rue Molière, Domaine Universitaire, BP 96, 38402 Saint Martin d''Heres Cedex, France;5. Centre of Excellence in Water Resources Engineering (CEWRE), University of Engineering & Technology (UET), — Lahore, Pakistan;6. International Water Management Institute, 12 km Multan Road, Chowk Thokar Niaz Baig, 53700 Lahore, Pakistan |
| |
| Abstract: | Rivers draining the southern Himalaya provide most of the water supply for the densely populated Indo-Gangetic plains. Despite the importance of water resources in light of climate change, the relative contributions of rainfall, snow and glacier melt to discharge are not well understood, due to the scarcity of ground-based data in this complex terrain. Here, we quantify discharge sources in the Sutlej Valley, western Himalaya, from 2000 to 2012 with a distributed hydrological model that is based on daily, ground-calibrated remote-sensing observation. Based on the consistently good model performance, we analyzed the spatiotemporal distribution of hydrologic components and quantified their contribution to river discharge. Our results indicate that the Sutlej River's annual discharge at the mountain front is sourced to 55% by effective rainfall (rainfall reduced by evapotranspiration), 35% by snow melt and 10% by glacier melt. In the high-elevation orogenic interior glacial runoff contributes ～30% to annual river discharge. These glacier melt contributions are especially important during years with substantially reduced rainfall and snowmelt runoff, as during 2004, to compensate for low river discharge and ensure sustained water supply and hydropower generation. In 2004, discharge of the Sutlej River totaled only half the maximum annual discharge; with 17.3% being sourced by glacier melt. Our findings underscore the importance of calibrating remote-sensing data with ground-based data to constrain hydrological models with reasonable accuracy. For instance, we found that TRMM (Tropical Rainfall Measuring Mission) product 3B42 V7 systematically overestimates rainfall in arid regions of our study area by a factor of up to 5. By quantifying the spatiotemporal distribution of water resources we provide an important assessment of the potential impact of global warming on river discharge in the western Himalaya. Given the near-global coverage of the utilized remote-sensing datasets this hydrological modeling approach can be readily transferred to other data-sparse regions. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
