As atmospheric CO2 concentration increases, its solubility into the earth's oceans also increases. The increase of CO2 concentration in the surface sea water is making the oceans more acidic, by reacting with the water to form carbonic acid. Also, the abundance of protons in the water is decreasing the carbonate saturation of the water. Many creatures, including coral reefs and, well anything that lives in a shell, uses the carbonate ions in the water to precipitate calcium carbonate which makes up their skeletal structures. Ocean acidification is a major problem with devastating effects that are happening right now. The major differences between this problem and global warming are, first, the acidifying effects of atmospheric CO2 rely on BASIC chemistry to produce the hypothesis, not models or projections; second, the changes may happen so suddenly that adaptive tendencies of a species may not have time to cope with a changing environment. This means that when the ocean pH reaches the calcification threshold, these species would be lost, forever. I have been surprised at how little attention this problem has been given. I found one group working towards a solution. An open source project called Cquestrate has an idea that would, potentially, reduce atmospheric CO2, actually turning back the clock on climate change, while, at the same time, mitigating ocean acidification. This slide show explains the process http://www.cquestrate.com/the-idea/slideshow-presentation
It seems to me that without communication from all disciplines of science with industry and policy making, solving climate change will never happen, and, disturbingly, we may make a mistake that would make matters worse.