Carbon emissions threaten marine species

No one had great expectations about the outcome of discussions on climate change at the recent G8 summit of the world's wealthiest nations in Scotland, and the modest resulting statement did little to reassure researchers that the topic is being taken as seriously as many feel it demands. " At the heart of the communique is a disappointing failure by the leaders of the G8 unequivocally to recognise the urgency with which we must be addressing the global threat of climate change, " commented Britain's science academy, the Royal Society. Just ahead of the meeting, the society produced a report highlighting just one of the consequences of growing human-derived carbon dioxide emissions to the atmosphere: increasing acidity of the oceans as the waters absorb growing volumes of the greenhouse gas. Failure to address the issues " may mean that there is no place in the oceans of the future for many of the species and ecosystems that we know today, " said John Raven, chair of the group that produced the report. The oceans cover two-thirds of the Earth's surface. They play a vital role in global biogeochemical cycles, contribute enormously to the planet's biodiversity and provide a livelihood for millions of people. " The oceans are absorbing carbon dioxide from the atmosphere and this is causing chemical changes by making them more acidic, that is decreasing the pH. In the past 200 years the oceans have absorbed approximately half of the carbon dioxide produced by fossil fuel burning and cement production, " the report says. " Ocean acidification is serious and its impact on the climate will be irreversible, " said Raven. Calculations based on measurements of the surface oceans and knowledge of ocean chemistry indicate that this uptake of carbon dioxide has led to a reduction of the pH of surface seawater of 0.1 units, equivalent to a 30 per cent increase in the concentration of hydrogen ions. " If global emissions of carbon dioxide from human activities News focus Carbon emissions threaten marine species Researchers, increasingly frustrated at the political response to the evidence of climate change as a result of human-derived carbon dioxide emissions, are still reporting new worries. A recent report highlights the impact of the emissions on the acidity of the oceans and the possible consequences. Nigel Williams reports. Acid challenge: many organisms that use calcium to build body structures may find their future …