Guardian: Huge vents covering the sea-floor – among the strangest and most spectacular sights in nature – pour carbon dioxide and other gases into the deep waters of the oceans. Last week, as researchers reported that they had now discovered more than 50,000 underwater volcanic springs, they also revealed a new use for them – as laboratories for measuring the impact of ocean acidification on marine life. The seas are slowly being made more acidic by the increasing amounts of carbon …