The significance and management of natural carbon stores in the open ocean
This report focuses on the open ocean, which is often referred to in the literature as the largest carbon sink on Earth. The report has been produced to promote better understanding of how atmospheric carbon is captured, stored and mobilized in the ocean, and how this has a significant bearing on sustainability, the welfare of people, and the future scale and intensity of climate change and ocean acidification. Whilst there has been a significant effort on managing carbon in natural environments on land in places such as forest and peatlands, we have been largely ignoring the ocean that is now responding to the full impact of the consequences of our activities.
The report sets out the importance of carbon in the open ocean and, through examples, illustrates the significance and values of some of its major carbon pools and sinks. This analysis ranges from microscopic organisms in the plankton that drive the biological pump, which take CO2 out of the air and ultimately trap a proportion of solid carbon permanently in the sediments of the deep ocean, through to groups of animals, which perhaps hitherto have not been considered as very relevant in carbon management, such as krill and fish – and in so doing introduces the notion of ‘mobile carbon units’. The report ranges in its attention from the surface waters, where carbon capture is powered by photosynthetic activities, through to the deep ocean. It describes the role and importance of deep sea microbes, and the recently discovered, increasingly important chemosynthetic pathways through which carbon is converted in the deep dark ocean to organic matter.