Microscopic Life and Chemical Cycling

Marine Life and Chemical Cycling

In the next five years, we aim to take significant steps in the advancement of our knowledge concerning marine microscopic life and large-scale cycling of major chemicals

The Challenge

The ocean is home to billions of microscopic plants (phytoplankton) and the organisms which consume them (Zooplankton). Zooplankton are food for the fish that sustain the major supplies of protein that people draw from the ocean. Phytoplankton photosynthesis converts the carbon dioxide that enters the surface ocean from the atmosphere into organic matter, some of which sticks together into large particles visible to the naked eye known as marine snow. When this material sinks it transfers carbon from the upper ocean to the interior helping to keep our climate the way it is today. The controls over this process include the availability of nitrogen, phosphorus, silicon and iron, elements which we collectively refer to as nutrients. Therefore the supply of these elements to the ocean from rivers and the atmosphere, coupled to their oceanic cycling, regulate our climate and the living marine resources we harvest from the ocean. 

Our Research

NOC has a large research programme focused on the role microscopic life plays in regulating our climate. Key research foci include the amount of carbon fixed by organisms in the upper ocean, how much of this material sinks out of the upper ocean and the fate of this material in midwater regions. We use satellites, autonomous platforms and shipboard expeditions to key regions such as the North Atlantic, Southern Ocean and tropical waters to determine these elements in different biomes. An important strand of our work is observing sinking material and balancing the production of this material against the consumption term in different places and depth layers of the ocean.

How this provides a benefits to society

A major beneficiary of this work is the numerical modelling effort that underpins our ability to predict the future evolution of our climate. The UK Earth System model contains a marine biological component that is, due to necessity, a simplified representation of reality. Our work helps to both improve and constrain the working of this modelling effort, thereby improving the quality of the model predictions the UK feeds into the IPCC process. Ultimately this allows us to more accurately determine the impact of future patterns of energy generation on how our planet will evolve, as well as to take mitigation measures informed by the best possible evidence base available.