Scientists reveal ocean acidification from space

In a technology that can revolutionise the way marine biologists and climate scientists study the ocean, British scientists have revealed ocean acidification from space.

The new approach offers remote monitoring of large swathes of inaccessible ocean from satellites that orbit the Earth some 700 km above our heads.

"Satellites are likely to become increasingly important for the monitoring of ocean acidification, especially in remote and often dangerous waters like the Arctic," said Jamie Shutler from University of Exeter who is leading the research.

It can be both difficult and expensive to take year-round direct measurements in such inaccessible locations.

"We are pioneering these techniques so that we can monitor large areas of the Earth's oceans allowing us to quickly and easily identify those areas most at risk from the increasing acidification," he added.

Each year, more than a quarter of global CO2 emissions from burning fossil fuels and cement production are taken up by the Earth's oceans.

This process turns the seawater more acidic, making it more difficult for some marine life to live.

Rising CO2 emissions and the increasing acidity of seawater over the next century has the potential to devastate some marine ecosystems "a food resource on which we rely" and so careful monitoring of changes in ocean acidity is crucial.

The new technique uses satellite mounted thermal cameras to measure ocean temperature while microwave sensors measure the salinity.

Together, these measurements can be used to assess ocean acidification more quickly and over much larger areas than has been possible before.

A number of existing satellites can be used for the task. These include the European Space Agency's Soil Moisture and Ocean Salinity (SMOS) sensor that was launched in 2009 and NASA's Aquarius satellite that was launched in 2011.

The development of the technology and the importance of monitoring ocean acidification are likely to support the development of further satellite sensors in the coming years.

The paper appeared in the journal Environmental Science and Technology.