Ocean Acidification

The effects of ocean acidification on all calcifying organisms is still debated; however, most studies show an overall negative impact on marine calcification organisms. 

There are many ways you can help:

http://ocean.si.edu/ocean-news/how-you-can-help-ocean

http://www.coral.org/node/4258

http://action.biologicaldiversity.org/p/dia/action/public/?action_KEY=2700

http://ocean.nationalgeographic.com/ocean/critical-issues-ocean-acidification/