Ecosystem modelling
Phytoplankton are microscopic algae that grow in the surface waters of the ocean and, like plants on land, consume carbon dioxide (CO2), which is absorbed into the ocean from the atmosphere. The growth of the phytoplankton depends on sunlight and on their supply of nutrients. This supply is in turn influenced by ocean circulation, including eddies, currents, and vertical processes, such as mixing, that bring nutrients to the surface from deeper waters in the ocean. Just how these mechanisms operate, and how they will change in the future, is not well understood.
Computer models, that represent the interactions between physical and biological processes, can help us to understand the role that marine life plays in regulating atmospheric CO2 and how this will respond to future climate change.
Here at NOC, we are developing complex models of the world’s oceans, which include the role of marine life, in order to address the following questions:
- How do physical processes in the ocean, such as eddies and vertical mixing, influence the distribution of biological activity in the ocean?
- How do different nutrient cycles (carbon, nitrogen, silicon, iron) interact to regulate the activity of phytoplankton?
- What are the consequences for higher trophic levels, such as zooplankton and fish, of success of different phytoplankton groups in different oceanic areas?
- How is ocean acidification, caused by CO2 from the atmosphere dissolving into the upper ocean, affecting sensitive marine organisms such as algae and corals?
- What are the effects of changing circulation and associated marine ecosystem dynamics on the so-called ‘biological pump’ – the rain of sinking dead organic matter from the surface to the deep ocean, which serves to capture carbon from the atmosphere?
