HR: 09:15h
AN: GC51B-06    [Abstracts]
TI: Assessing the Impact of Land Use and Land Cover Change on Global Water Resources
AU: * Batra, N
EM: nbatra2@uiuc.edu
AF: University of Illinois at Urbana-Champaign, Dept. of Civil and Env. Engg. 205 North Mathews Av. Hydrosystems Lab, Urbana, IL 61801, United States
AU: Yang, Y E
EM: yang24@uiuc.edu
AF: University of Illinois at Urbana-Champaign, Dept. of Civil and Env. Engg. 205 North Mathews Av. Hydrosystems Lab, Urbana, IL 61801, United States
AU: Choi, H I
EM: hichoi@uiuc.edu
AF: Illinois State Water Survey, 2204 Griffith Drive, Champaign, IL 61820, United States
AU: Islam, A
EM: a.islam@cgiar.org
AF: International Water Management Institute, 127, Sunil Mawatha, Pelawatte, Battaramulla, Sri Lanka., Colombo, 2075, Sri Lanka
AU: Charlotte, D F
EM: c.fraiture@cgiar.org
AF: International Water Management Institute, 127, Sunil Mawatha, Pelawatte, Battaramulla, Sri Lanka., Colombo, 2075, Sri Lanka
AU: Cai, X
EM: xmcai@express.cites.uiuc.edu
AF: University of Illinois at Urbana-Champaign, Dept. of Civil and Env. Engg. 205 North Mathews Av. Hydrosystems Lab, Urbana, IL 61801, United States
AU: Kumar, P
EM: kumar1@uiuc.edu
AF: University of Illinois at Urbana-Champaign, Dept. of Civil and Env. Engg. 205 North Mathews Av. Hydrosystems Lab, Urbana, IL 61801, United States
AB: Land use and land cover changes (LULCC) significantly modify the hydrological regime of the watersheds, affecting water resources and environment from regional to global scale. This study seeks to advance and integrate water and energy cycle observation, scientific understanding, and human impacts to assess future water availability. To achieve the research objective, we integrate and interpret past and current space based and in situ observations into a global hydrologic model (GHM). GHM is developed with enhanced spatial and temporal resolution, physical complexity, hydrologic theory and processes to quantify the impact of LULCC on physical variables: surface runoff, subsurface flow, groundwater, infiltration, ET, soil moisture, etc. Coupled with the common land model (CLM), a 3-dimensional volume averaged soil-moisture transport (VAST) model is expanded to incorporate the lateral flow and subgrid heterogeneity. The model consists of 11 soil-hydrology layers to predict lateral as well as vertical moisture flux transport based on Richard's equations. The primary surface boundary conditions (SBCs) include surface elevation and its derivatives, land cover category, sand and clay fraction profiles, bedrock depth and fractional vegetation cover. A consistent global GIS-based dataset is constructed for the SBCs of the model from existing observational datasets comprising of various resolutions, map projections and data formats. Global ECMWF data at 6-hour time steps for the period 1971 through 2000 is processed to get the forcing data which includes incoming longwave and shortwave radiation, precipitation, air temperature, pressure, wind components, boundary layer height and specific humidity. Land use land cover data, generated using IPCC scenarios for every 10 years from 2000 to 2100 is used for future assessment on water resources. Alterations due to LULCC on surface water balance components: ET, groundwater recharge and runoff are then addressed in the study. Land use change disrupts the hydrological cycle through increasing the water yield at some places leading to floods while diminishing, or even eliminating the low flow at other places.
DE: 1630 Impacts of global change (1225)
DE: 1632 Land cover change
DE: 1637 Regional climate change
DE: 1836 Hydrological cycles and budgets (1218, 1655)
DE: 1843 Land/atmosphere interactions (1218, 1631, 3322)
SC: Global Environmental Change [GC]
MN: 2007 Fall Meeting