Deadline: 6th January 2014.
Supervisor: Dr Giorgio Dall’Olmo [email protected] Â
The Biological Carbon Pump comprises all the biologically-mediated processes by which carbon is removed from the ocean surface and transported at depth. Over long time scales this pump is thought to contribute to controlling the Earth’s climate, but large uncertainties remain regarding its global magnitude and spatio-temporal variability. These uncertainties largely arise from lack of observations.
The greatest contributors to the Biological Carbon Pump are particles generated near the surface by photosynthesis and consumed, as they settle, by heteroptrophic organisms (respiration). Photosynthesis and respiration are opposite processes.Â One should expect, therefore, a clear relationship between the supply of organic carbon to the deep ocean and the consumption of oxygen. Instead, current measurements suggest that significantly more oxygen is consumed than carbon supplied. This is one of the most intriguing and unanswered questions regarding the Biological Carbon Pump.
One proposed explanation for the above paradox is that current methods for estimating carbon fluxes at depth are missing the component of the carbon flux that is carried by slowly-settling particles. These slowly settling particles could account for up to 60% of the total suspended particulate carbon. Thus, it is fundamental to understand the dynamics of these particles.
Slowly settling particles are expected to be small and therefore challenging to observe. Fortunately, the abundance of small particles is registered by optical scattering. Scattering measurements can also be collected by robots autonomously floating in the ocean (Bio-Argo floats). Data from these novel platforms are now suggesting that small-particles fluxes could indeed be of comparable magnitude to particle fluxes measured by traditional techniques. Bio-Argo floats can also measure other fundamental biogeochemical variables such as the concentration of dissolved oxygen. These data, therefore, have a tremendous potential for shedding new light on fundamental carbon cycle questions.
The overall aim of this Ph.D. will be to assess the balance between small-particle fluxes and oxygen budgets in the upper 1000m of the water column. The study will focus on the Nordic Seas. Specific objectives will involve:
â¢Â Quantification of primary production, carbon fluxes, and oxygen budgets by exploiting in-situ float measurements as well as satellite ocean colour images.
â¢Â Quantification of the Biological Carbon Pump characteristics (strength, efficiency, temporal and spatial variability) in the study area.
â¢Â Quantification of the mesopelagic budget of carbon supply and oxygen demand.
For information contact: Dr. Dall’Olmo ([email protected]).
This project has been shortlisted for funding by the newly-created ENV East Doctoral Training Partnership (DTP) â a collaboration led by the University of East Anglia, with the Universities of Essex and Kent, and twenty other partners. Shortlisted applicants will be interviewed as part of the Studentship Competition. The interview dates will be 14th and 15th February 2014 at one of the three Universities listed above.
First degree (2.1) in a relevant area of study.
Funding is available for this project. For full details visit: www.uea.ac.uk/study/postgraduate/research-degrees/science/environmental-sciences.
To discuss the application process or particular projects, please contact the:Â Admissions Office, email: [email protected] or telephone +44 (0)1603 591709.Â