Australia: The Commonwealth Scientific and Industrial Research Organisation (CSIRO) has developed a way of using remote sensing (RS) technology to provide information about inland water quality. Over a 10-year investment strategy, CSIRO has developed a way of using remote sensing techniques to remotely detect ‘visually active’ water quality variables in marine coastal waters.
By measuring the colour of the water in detail, variables such as chlorophyll, cyanobacterial pigments, organic and inorganic sediments as well as dissolved organic matter can be quantitatively observed. The approach of measuring water colour works for instruments in close proximity to the water surface or for satellite sensors based hundreds of kilometres in space.
CSIRO has developed an algorithm based on physics-based adaptive linear matrix inversion (aLMI) which can simultaneously derive concentrations of a number of water quality variables over different water types. The Great Barrier Reef Marine Park Authority now uses this technique for systematic and cost-effective assessment of water quality variables in the Great Barrier Reef lagoon using satellite data.
The current one-year project will investigate the application of the aLMI to develop this same capability for Australia’s inland waters. The algorithm will require different optical datasets to cope with the greater range of water quality that exists in inland waters. One of the project objectives is to collate and evaluate existing datasets and develop new datasets for variables relevant to Australian inland waters.
As well as testing the method on satellite data, the project will also test novel, ‘near-surface sensing’ approaches to provide continuous water quality monitoring. These methods will be validated against traditional sampling methods.
Initial demonstration projects for near-surface sensors and satellite retrievals are proposed in the Murray-Darling Basin and in Queensland where a range of water types provide opportunities to investigate the robustness of the approach, covering a range of hydrological conditions, sediment events, algal blooms and black water events.