Ocean biogeochemistry and ecosystems (OBE) research at the NOC is multidisciplinary; studying ocean physics, chemistry and biology using leading modelling and instrumentation techniques to understand ocean biogeochemistry and biodiversity.
The aim of our research is to address the ways in which the growth of biological communities in the ocean are regulated, the roles such communities play in the global climate system and the influence of global change on these communities.
Much of our research is motivated by the magnitude of the biological carbon pump (BCP), the biological mechanism by which carbon is stored in the oceans interior. It is several times larger than the annual accumulation of CO2 in the atmosphere, and without it atmospheric CO2 would be significantly higher than it is today. Basic information regarding its structure, stability and functioning is needed to assist in predicting future atmosphere-ocean CO2 partitioning.
We study the impact of the ocean circulation on the marine ecosystem at all scales, from the size of whole oceans to less than a kilometre. In particular we study the influence of physical processes on ‘primary productivity’, the uptake of carbon dioxide, through photosynthesis, by the multitude of tiny marine plants called phytoplankton, which form the base of the marine ecosystem.
For many years, the NOC has studied how life in the deep sea might be influenced by the changing of the seasons, in other words ‘deep seasonality’. More recently, we have broadened our work to study topics like the longer-term influence of climate and increasing industrial activity in the deep sea.
We provide information on the dynamics of animals, habitats, and processes over a range of space and time scales, both at and above the deep seafloor. Our work includes observation, experiment, and theory. We are involved in new technology development to further our science. We carry out original research and support the UK and European marine science strategies with the aims of scientific discovery and the sustainable use of deep-sea resources.
Export and Particle Flux
Microscopic plants grow in the upper sunlit zone of the ocean, the start of a complex range of interactions and exchanges, which constitute the marine food web. Although most of the action takes place within the top few tens of meters of the surface, some of the material sinks into the deeper water to fuel the biological communities in the dark ocean. This process of sinking also removes carbon from the ocean surface thus encouraging the oceans to take up more CO2 from the atmosphere where it enhances global warming. If we are to understand this process of sinking and the factors that affect it, one of the crucial factors to determine is the quantity and characteristics of material settling down through the different layers of the water column.
We aim to address the processes by which material leaves the upper sunlit zone, the factors that affect this export and the way the settling material changes as it sinks through the water column fuelling life in the dark ocean and ultimately the organisms living on the deep-sea floor.
NOC research on microbial plankton seeks to determine the functional roles of dominant microbial groups in oceanic pelagic ecosystems. We have a particular interest in the microbial biogeochemistry of the oligotrophic (nutrient-poor) oceanic gyres, which are the most spatially extensive biomes on Earth (they cover more than 40% of the Earth’s surface), and which are expanding under the influence of climate change. Sunlight-fuelled, microbially driven carbon sequestration and nutrient dynamics in the surface waters of the gyres should have a significant but uncertain feedback effect (which is a subject of our studies) on global carbon cycling and climate.
Carbon and Nutrient Dynamics
Microscopic phytoplankton control many of the chemical processes that occur in the ocean. These wonderfully diverse plant-like organisms provide food for the entire marine food chain, produce much of the oxygen that we breathe and help to remove carbon dioxide (CO2) from the atmosphere. Without the oceans, the high concentrations of carbon dioxide that have accumulated in the atmosphere from human activities such as, fossil fuel burning and the removal of the rain forests, would be much higher. By removing CO2, the phytoplankton counteract these emissions, which are causing global warming, but in turn they also produce other gases that may contribute to it. Hence, our research focuses on the role of the ocean in climate change and how this role may change in the future.
We make measurements from a wide range of observing platforms including research vessels, time series stations and ships of opportunity and also carry out experiments in the laboratory and on ships. We use our data to better understand ocean processes and also to develop computer models that simulate the phenomena we observe and this helps us to further understand the processes on a global scale. To do our work we need to develop instruments and sensors, not only to make the measurements but also to collect the samples from the ocean so that they can be processed back in the laboratory. Some of this work is very complex, particularly when developing new chemical methods to analyse our samples and when ensuring that the sensors are working correctly in the harsh marine environment and giving us the information we need. We undertake our science from the shallow coastal seas to the open ocean and from ocean depths to the surface also determining the rate at which chemicals enter and leave the ocean at the surface, the so called air-sea interface. With all this information we can extend our knowledge of the ocean’s role in global system and predict the effects of climate change.