Is it really "bad" for life if the oceans are acidifying under so much CO2? CO2 levels were much higher 100 million years ago and I'm sure this implies that ocean acidity was also higher 100 million years ago. And yet, marine life still thrived. Not the same kind of marine life as today, but a different kind of marine life. There will be new creatures that will fill in the gap caused by ocean acidification. Maybe, it might take a long time (by human standards). And of course, coral reefs (and the creatures that depend on them) might be irreplaceable (and seen as more valuable than the marine organisms of, say, 100 million years ago). But really, who's to determine which organisms have any more right to life than any other organisms? Although one of the issues is that extinctions will happen before new species evolve, and extinctions will cause a loss of information that we could get from the unique physiologies/social structures of various organisms. I'm not anti-environmentalist by any measure - in fact - I hate habitat destruction more than anything else simply because it prevents other organisms from filling in the void caused by localized extinctions.