Carbon dioxide emissions are altering the chemical balance of the oceans, as acidification threatens the marine ecosystems that provide livelihoods to millions around the world. Carol Turley explains.

• 二氧化碳排放正改变着海洋的化学平衡，卡罗尔?特里解释说，酸化将威胁海洋生态系统，而全世界有千百万人依靠它生活。