 We are on One Tree Island in the southern Great Barrier Reef. One Tree Island is in a research-only zone and that makes it perfect for studying coral reefs because it's not impacted by fishing or tourism. One Tree Island itself is a fairly large lagoon that's several kilometres long by several kilometres wide. So there are all these special environments on the outside reef and also inside the lagoon as well. What we're walking along is the reef flat. This area is really important because this is the bit that cements the reef together and makes the stable platform for One Tree Island to be located upon. The reef flat also dissipates all the energy that comes towards One Tree. So if you have big storms, it takes away the energy and so the island can remain. Without this reef flat that's cemented together, we wouldn't have an island here basically. As there's more carbon dioxide emissions in the atmosphere, the ocean actually absorbs some of that carbon and in fact quite a lot of that carbon and so we're seeing an increased concentration of carbon in the ocean waters and that's actually not good for the reef because it changes the acidity of the water. You can almost think of the reef like a house where it's made up of bricks and cement where the corals form these big blocks that are the bricks of the reef making the main structure and other organisms make the cement that holds all these blocks together. So the worry is that as acidification continues in the future these cements might start to dissolve away leaving the house to crumble. If we can better understand what's happening here hopefully we can better manage reefs like One Tree Island into the future.