NASA mission a game changer for coral reef science

Coral reefs are in danger

Coral reef ecosystems are very fragile, with small environmental changes in sea level, water temperature or water quality having an enormous impact. NASA estimates that between 33 to 50 per cent of our planet’s coral reefs have been significantly degraded or lost, and there is a growing concern that most functioning reef ecosystems across the world will disappear by mid-century.

With the long term viability of places like the Great Barrier Reef at risk, it is essential to collect relevant information about these unique ecosystems to understand why and how reefs change in response to environmental fluctuations.

To date, most records of coral reefs have been taken manually from someone diving the reef and recording their observations. Ariel surveys using spotters and photographers as well as Landsat satellites and unmanned underwater vehicles have also provided very useful data, but all of these methods have limitations because of the vast size of the reef.

New technology takes to the skies

New technology created at NASA’s Jet Propulsion Laboratory (NASA-JPL) can now measure reef conditions using an airborne imaging spectrometer dedicated to aquatic environments installed in an aeroplane. The Coral Reef Airborne Laboratory (CORAL) will help scientists predict the future state of coral reefs like the Great Barrier Reef by providing critical data and new models needed to analyse the current status of the reef. This is the first dedicated aquatic environment imaging spectrometer ever flown in Australia.

CORAL acquires airborne spectral image data using the Portable Remote Imaging Spectrometer (PRISM) instrument installed in an aeroplane that then transects large areas of the reef.

This data will be used in conjunction with in-water measurements to provide a more detailed spatial analysis of the Great Barrier Reef and take coral reef research to a new level.

During the Australian part of the mission, CSIRO researchers will work with the CORAL team, performing in-water validation in the Torres Strait and through various parts of the Great Barrier Reef while onboard the blue-water research vessel, Investigator, which is operated by the CSIRO Marine National Facility.

A game-changer for coral reef health

During a three-year field expedition, NASA will use this technology to survey reefs systems in Florida, Hawaii, Palau, the Mariana Islands and The Great Barrier Reef.

It will record uniform data of a cross-section of the reef to give the most thorough picture of reef conditions to date.

It will highlight key marine health indicators such as benthic cover of coral, algae and sand cover, bio-optical properties of the water, primary productivity and calcification.

Integrating high resolution sensing into reef surveys allows scientists to scale-up their research in a way that is more relevant to the ecosystem. Scientists will be able to look for trends in coral reef condition and biogeophysical factors – both natural and man-made – to give a more meaningful understanding of the current state of the reef. They will then have the tools to more accurately model these impacts and mitigate against changes.

Significant scientific methodology has already gone into creating models that show what is happening in the reef ecosystem, and how it is changing. The NASA mission will provide the data needed to calibrate these models.

This is a pre-orbital mission which, if successful, could lead to a space-based imaging spectrometer accurately and constantly measuring changes in all coral reefs across the globe.