Mercury: GLOBAL warming could dissolve the shells of marine life as oceans become more acidic, scientists in Hobart said yesterday. Shell-life in the Southern Ocean will face the acid test first, because colder waters will become acidic faster. Researchers investigating the effects of ocean acidity left Hobart aboard the Aurora Australis yesterday — its first voyage for the summer season. A major focus of research in Antarctica this season will be the future of shells in an …