Earth’s oceans in peril

Climate change has already had such a devastating effect on the world’s oceans that future damage from rising and warming seas is now unavoidable, according to a new United Nations report. Since 1970, oceans have absorbed 90 percent of the excess heat generated by carbon pollution in the atmosphere, as well as much of the carbon dioxide itself. This has triggered profound changes in oceanic chemistry. Upper layers of open ocean are holding less oxygen and becoming more acidic, wreaking havoc on marine ecosystems. The frequency of marine heat waves, blamed for mass die-offs of coral reefs and other ocean habitats, has doubled since the 1980s. Even if humanity manages to massively slash carbon emissions in coming decades, the negative effects of climate change will continue, the report found. In the best-case scenario, sea levels are still expected to rise by 1 to 2 feet over the next century because of melting glaciers and sea ice. Andrew Pershing, chief scientific officer at the Gulf of Maine Research Institute, tells NPR.org, “That means, no matter what we do, we have to figure out how are we going to adapt to these changes.”

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