NOAA's Aquarius Reef Base is the only undersea research station operating in the world today. Located just three and a half miles offshore from Key Largo, Florida, at a depth of 60 feet, aquanauts spend ten day missions living and working on the seafloor. Changing Seas observed scientists during a recent mission as they studied the impacts ocean acidification is having on local reef ecosystems. Ocean acidification is caused by a change in the water's chemistry that could have potentially devastating impacts on corals in the future.