WCR: Effect of Changes in Climate, Snow Pack, Glaciers, and Permafrost on River Runoff in Tien Shan, Central Asia

点击翻译按钮获取中文摘要

0233583Aizen The evaluation of the long-term dynamics of water cycle components in the World's largest closed drainage system has not been examined in detail. Location of the Tien Shan and rich data provide a unique opportunity to assess the pathways of water among hydrological surface and subsurface reservoirs and to quantify the precipitation partitioning among land surface stores with different residence times. The main objective of our research is estimating, simulating, and predicting the variability in water cycle components and water composition in the Central Asian alpine basins. This project proposes to: (1) Provide background information and evaluate the long-term changes in type and quantity of precipitation, evaporation, total river runoff and snow/glacier/permafrost runoff, major ions, pH, conductivity, and dissolved oxygen. This data will be posted at the University of Idaho web site (www.mines.uidaho.edu/~aizen/aizen.html). (2) Discover the controls on the water chemistry (changes in glacier, snow, and permafrost river runoff, atmospheric deposition, rock weathering, etc.). Define the input/output chemical budget emphasizing on the watershed geology. (3) Implement modular-design, deterministic, distributed-parameter modeling systems: i.e., "Precipitation Runoff Modeling System" and/or snow-ice simulation with "Snowmelt Runoff Model" in application with the operational runoff modeling, which simulates active layer freezing and thawing. Geochemical modeling includes specification of the various elements and determination of saturation indices for various metals based on MINTEQA2 and WATEQ. Mass-balance calculations will be facilitated by computer codes such as BALANCE, NETPATH and PHREEQE. Validation of simulation results will be based on data sets other than those used in model calibration. (4) Develop and validate the transition from small hydrological units to complex geographical systems through the scaling relationships and to determine the distribution of point measurements. Three representative sub-basins will be used to determine water balances using data during each time step (daily, monthly, seasonally, and annually). (5) Apply climate scenarios to assess the climate-driven impact on future water resources and model the effect of global warming on water chemistry. The basis of this integrative research is the collaboration with the Central Asian, the USA, the Japan, and the Chinese institutions.