Rising levels of carbon dioxide in the atmosphere are a major cause of climate change, and now a new study has confirmed that atmosphere CO2 is also affecting the ocean chemistry and potentially harming sea life. Montana State University scientist Robert Dore has been researching the water in the Pacific Ocean for almost two decades. “We’ve been going to the same spot in the Pacific Ocean, and we try and characterize long-term change in the open ocean environment. And one of the key things that we measure is CO2 levels. And we’ve been able to record this increasing quantity of atmosphere CO2 into the ocean.” Scientists expected that as atmosphere CO2 increased, more and more of the carbon dioxide would be absorbed into the ocean, affecting the chemical balance of the sea water, with a potentially harmful impact on shellfish and coral in particular. “As carbon dioxide dissolves in the water or seawater in this case, it forms a weak acid, carbonic acid,” Dore explains. “And therefore, as the concentration of CO2 in the atmosphere goes up and that exchanges with the surface seawater, it drives the pH down, and makes it more acidic.” The seawater samples Dore and his colleagues have analyzed confirm what the theory predicts. The effect was particular striking at about 250 meters down, and again at 500 meters. Dore and his colleagues came up with two possible explanations. It could be that surface water picked up CO2 and then moved to those depths. Or there could be a biological explanation. “It’s important to realize that the oceans are really becoming acidic. And it can have negative impacts on a whole variety of sea life from fish to coral. It’s potentially catastrophic.” 小题1:What can be the best title of the passage?
a. Sea life is endangered. b. CO2 goes into the surface water. c. The ocean chemistry is affected. d. CO2 decreases the pH and makes the seawater more acidic. e. CO2 levels in the atmosphere go up.
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