High-CO2 reefs: Where the future has already arrived

A brown-greenish lunar landscape covers the seafloor in some bays of Papua New Guinea. Poor in species, monotonous and separeted from the divers surroundings by curtains of rising bubbles. Is this what the future of tropical coral reefs looks like?

The volcanic carbon dioxide vents in the South Pacific archipelago provide scientists with a glimpse of the future. The gas causes the water to acidify. But only a few coral species such as the Porites genus are able to maintain their growth and reproduction at lower pH. And only algae and sea grasses can exist at locations of extreme acidities. Fish and other non-sessile creatures seem to avoid these areas.

In addition to ocean acidification, tropical coral reefs are also exposed to rising water temperatures. Therefore, the High-CO2-Reefs of Papua New Guinea make up an excellent natural laboratory for research on impacts of ocean acidification – but many other findings from other experiments and model calculation need to be considered in order to create a comprehensive projection.

In this video portrait, BIOACID scientist Dr. Christiane Hassenrück tells about her expedition to the high-CO2 reefs and her research on microorganisms – tiny bacteria that play a crucial role for these ecosystems.