Earth observation

Whilst water quality sensors in-situ provide highly accurate data, they are restricted to the specific area where they are installed.

Earth observation (EO) data is the collection of satellite and in-situ information about Earth’s surface and it’s physical, chemical and biological systems. It provides unprecedented capabilities and efficiencies in monitoring the dynamics of our planet.

EO data from satellites can detect water quality issues like algal blooms and sediment plumes using colour signatures visible from space. AquaWatch uses high-quality satellite imagery in combination with its water-based sensors and data analytics to support continental-scale water quality monitoring.

AquaWatch leverages this technology to measure water quality issues from 600 kilometres away in space. By doing so, it delivers critical data for managing health, environmental impact and industrial activities.

CSIRO is working with space technology partners to design the optimal satellite imaging system for high quality and high-resolution measurement of water quality from space. CSIRO values our international partners who provide us access to EO data from their satellites.

Space technology: CyanoSense

In collaboration with Australian partners, the CSIRO Space Optics team has developed a compact hyperspectral imager for low-Earth orbit designed to detect blue-green algae in coastal and inland waterways. The presence of this algae can be used as an early indicator for potentially harmful algal blooms, which if not properly managed are a risk to aquatic ecosystems and cause significant economic impacts.

Measuring water quality from space is particularly challenging as imaging targets are typically small, dark, and have narrow spectral fingerprints.

Addressing these challenges, the CyanoSense payload combines a high-resolution, precision manufactured telescope with a compact filter-based spectrometer and a high signal to noise ratio in the key spectral bands needed to detect cyanobacterial algal blooms.

Additionally, the payload is designed to be lightweight and compact, making it easy to integrate into existing satellite platforms and with on-board processing capabilities.

The development of specialised satellite sensors for water quality measurements, like CyanoSense, will enhance the AquaWatch system with higher quality data from space.

To better understand the data requirements the team consulted closely with Earth observation colleagues and Dr Mark Matthews (CyanoLakes), who provided the team with a study that helped inform the optimum spectral range and resolution of the imager.

The Space Optics team work closely with colleagues from the Institute for Photonics and Advanced Sensing (IPAS) at the University of Adelaide, where the team’s laboratory is located.