Oceans Absorbing Half of CO2 Emissions; Effects Uncertain

According to studies published today in the journal Science, the world’s oceans have absorbed almost half of all the carbon dioxide emissions created by humankind since the beginning of the industrial era — some 118 billion metric tons. Yowza! The good news is that by serving as a CO2 “sink,” oceans slow global warming — and they have the capacity to absorb much more. The bad news is that the massive increase in CO2 has made ocean water more acidic, impeding the ability of marine organisms like coral to form their outer shells; such organisms play a fundamental role in ocean ecosystems, and by the end of the century their deterioration could have untold effects on the entire chain of marine life. The dissolution of the calcium carbonate in the shells also changes water chemistry and could affect oceans’ CO2-bearing capacity in coming years.