AWRA-G: groundwater component of AWRA

[摘要] The Australian Water Resources Assessment (AWRA) model system developed by CSIRO for the Bureau of Meteorology (BOM) under the Water Information Research and Development Alliance (WIRADA) integrates a variety of models, data sources and analysis techniques to enable BOM to meet its requirements under the Water Act 2007 for undertaking annual water resource assessments and national water accounts. AWRA consists of several linked components using observations of elements of the water balance to account for water resources on a continental scale. The model components are: a landscape water balance model (AWRA-L), a river routing model (AWRA-L), and a groundwater component model (AWRA-G). These three component models combined are expected to be able to model the fluxes and stores of water throughout the landscape.The groundwater component (AWRA-G) addresses an improved representation of groundwater in the AWRA system to describe aquifer dynamics and groundwater-surface water processes. While most continental scale land surface models do not have the capacity to allow water to flow between cells and thus ignore this element of the water balance, AWRA-G does account for lateral flows. In general, AWRA-G is envisaged to provide estimates of groundwater fluxes that are not incorporated into either AWRA-L (van Dijk, 2010) and its modifications to in-cell soil and groundwater processes (Peeters et al., 2011), or AWRA-R (Frost et al., 2011; Leighton et al., 2011). The groundwater processes identified that are not incorporated into AWRA-L or AWRA-R and are integrated into AWRA-G are:•Lateral groundwater flow between AWRA-L cells in regional and intermediate groundwater systems•Groundwater extraction (pumping)•River losses to groundwater (from AWRA-R)•Recharge from overbank flooding •Groundwater discharge to the ocean•Interactions between deep confined systems and surficial groundwater systemsBasis of AWRA-G is a good knowledge of aquifer properties (e.g. water table, transmissivity, etc.) on a continental scale. Since information is sparse at the current stage, these properties have to be derived from known sources like digital elevation maps (DEM), geologic maps of Australia and general maps of groundwater flow systems using simplifying assumptions. As a first step such simplified input data serve as a good basis for testing and implementation of AWRA-G. Both, the derivation of simplified aquifer properties and the implementation of AWRA-G are described in this report.Very simple tests carried out with AWRA-G, exemplified on the Loddon catchment and the whole of Australia, show the general behaviour of water redistribution due to groundwater processes on a large scale.

[发布日期] 2012-06-29 [发布机构] CSIRO

[效力级别] Natural Resource Management [学科分类] 地球科学(综合)