A SCOTTISH scientist is to lead a major investigation into the threat to marine life being posed by the rising acidity of the world’s oceans, caused by pollution from greenhouse gases.
Professor John Raven, of the School of Life Sciences at Dundee University, will lead a working group of eminent scientists appointed by the Royal Society, the UK’s national academy of science.
Its task will be to assess all the available evidence on the extent of acidification in the world’s oceans and the potentially disastrous impact on marine life.
The Intergovernmental Oceanographic Commission recently reported that up to 25 million tonnes of the greenhouse gas carbon dioxide are being added to the oceans each day. Once in the water, carbon dioxide reacts to form carbonic acid.
Research carried out by scientists at the National Oceanographic and Atmospheric Administration in the United States estimated that the world’s oceans have taken up about 120 billion tonnes of carbon generated by human activities since 1800.
And a study published last year by the Livermore National Laboratory in the US suggested that the projected increases in carbon dioxide in the atmosphere could cause ocean pH values - the scale for measuring acidity - to change more rapidly than at any time over the past 25 million years.
Oceans absorb carbon dioxide from the atmosphere and this, in turn, increases the acidity of the water. And there are mounting concerns that the rising levels of the gas from the burning of fossil fuels such as oil and coal may be exacerbating the situation.
A spokesman for the Royal Society said the investigation was prompted by concerns for the "potentially catastrophic consequences for marine life" as a result of the world’s oceans becoming increasingly acidic, because of carbon dioxide pollution.
He said: "Currently, the impact of this rising ocean acidity on marine life is largely unknown. However, there are fears that it could particularly affect corals and sea creatures with hard shells. This is because acidification seems to decrease the availability of calcium carbonate from the water - which these creatures use to produce their hard skeletons.
"Increased acidity may also directly affect the growth and reproduction rates of fish, as well as affecting the plankton populations which they rely on for food, and have potentially disastrous consequences for marine food webs."
Prof Raven will contribute his specialist skills on how photosynthetic organisms acquire carbon to the working group’s investigation.
Prof Raven, who is a principal investigator in the Division of Environmental and Applied Biology at Dundee University, said: "Our oceans may be doubly besieged.
"The same pollution that we believe is heating the world’s oceans through global warming is also altering their chemical balance.
"This study will look at what impact increased acidity levels might have on marine life and re-emphasise the urgent need to respond to the spectre of climate change, an issue identified by the UK government as a priority for its presidency of G8 in 2005."
Prof Raven and his colleagues on the working group are due to publish their initial findings early next year.