A report assessing the suitability of a new approach to monitoring groundwater levels based on GRACE (Gravity Recovery and Climate Experiment) satellite data has been released by the Australian Government National Water Commission. Potential use of this technology could complement traditional direct observations, but at a lower cost.
The study found that more work is required before the estimates derived from GRACE satellite data can be reliably reconciled with current groundwater monitoring observations.
The likely causes of the discrepancies identified arise from the large spatial scale of the GRACE data collection, inaccuracies in modelling soil moisture storage, poor spatial sampling of the existing groundwater bores, and a lack of precise knowledge for converting groundwater levels into groundwater volumes.
The report recommends further studies into appropriate techniques to convert GRACE data into groundwater data through better modelling of soil moisture storage. This would involve additional collection of groundwater and soil data and/or identification or development of groundwater models at more detailed spatial scales.
The report is available to download for free from http://www.nwc.gov.au/publications/waterlines/71
