Updating what we know about ocean acidification and key global challenges

It is amazing to think that just ten years ago hardly anyone had heard of ocean acidification. It is now much more widely understood that the increasing amount of carbon dioxide (CO2) we are emitting into the air by our activities is reacting with the ocean to alter its chemistry and push it along the scale towards acidity and is, amongst other effects, reducing the availability of carbonate ions needed by many marine animals and plants to build their shells and skeletons. This paper from the International Ocean Acidification Reference User Group, in partnership with national research programmes, provides essential information, and highlights the actions needed on ocean acidification by Governments. There is little doubt that the ocean is under-going dramatic changes that will impact many human lives now, and ever more so in the coming generations, unless we act quickly and decisively. Previous acidification events in the Earth’s geological record were often associated with extinctions of many species. Whilst the causes of such extinction episodes are complex, it is notable that the biodiversity recovery took hundreds of thousands and – after mass extinctions – millions of years.