"Some researchers are seriously considering geoengineering to reverse the slow acidification of the ocean. Dissolving minerals like olivine or limestone into seawater would increase its alkalinity. (Remember the pH strip in your 10 gallon fish tank? Blue=alkaline, red=acidic.) Not only would that make it easier on marine life, but it would also allow the ocean-sponge to soak up more carbon dioxide from the atmosphere. Two British scientists proposed this idea last year in a paper in the journal Reviews of Geophysics, predicting that with a bit more research (and money) it may be possible to capture hundreds of billions to trillions of tons of carbon without messing up the marine ecosystem."

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"Time for artificial planet coolers? A cooling “sunshade” for the planet could reduce harmful coral bleaching and the number of hurricanes, which damage reefs. With the effects of climate change becoming increasingly apparent, the idea of squirting a cloud of sulphate aerosols into the upper atmosphere is being investigated by several groups of scientists. This would scatter some of the sun’s rays back into space, reducing the rate at which the Earth is warming."

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"Researchers are finding that kelp, eelgrass, and other vegetation can effectively absorb CO2 and reduce acidity in the ocean. Growing these plants in local waters, scientists say, could help mitigate the damaging impacts of acidification on marine life."

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"As a potential solution, Francesc Montserrat of the Royal Netherlands Institute for Sea Research and his colleagues are exploring whether a natural mineral can mop up unwanted acid in seawater. “We’re trying to put some numbers on the table so that if politicians decide that we need to do this in 10 to 15 years’ time, the research is there and we can say, ‘here are the problems you might be dealing with’,” he says."

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