Marine life threatened by high carbon dioxide levels
Oceans becoming more acidic as they absorb gas, study claims
LONDON Rising levels of carbon dioxide are harming all forms of marine life because the oceans are acidifying as they absorb the gas, German researchers have found.
Mollusks, corals and a class of creatures called echinoderms that includes starfish and sea urchins are the worst affected by the uptake of CO2 by the seas, according to a study released Sunday in the journal Nature Climate Change by researchers at the Alfred Wegener Institute in Bremerhaven. The gas forms carbonic acid when it dissolves in the oceans, lowering their pH level.
Creatures that show negative effects from acidification include commercial species such as oysters and cod. Given the pace at which carbon-dioxide emissions are growing, human emissions threaten to trigger extinctions at a faster pace than die-outs millions of years ago, according to the researchers.
“There is a danger that we’re pushing things too fast and too hard toward an evolutionary crisis,” Hans-Otto Poertner, one of the authors, said by phone.
The research was designed to look solely at the effects of the acidification caused by the carbon-dioxide emissions, according to Poertner.
“We are at a risk of causing extinctions,” Poertner said. “We cannot give with any certainty the year when people will start to report extinctions due to climate change. It depends on what temperature change and CO2 concentrations we allow.”