Prof R Lampitt, Dr S Painter
No more applications being accepted
Funded PhD Project (European/UK Students Only)
About the Project
A major proportion of anthropogenic CO2 is transported out of the upper sunlit zone as a result of a downward sedimentation of biogenic material. This downward “Biological Carbon Pump” (BCP) is highly variable on both seasonal and annual time scales owing to complex interactions between upper ocean physical dynamics and ecosystem structure and function. A small proportion of the settling material reaches the deep sea where it is sequestered for centuries and an even smaller proportion is incorporated into deep sea sediments and sequestered for millennia. Where time-series proxies for the BCP exist (such as deep sediment traps) they show striking variability on scales from days to years. It is still uncertain how this variability is controlled by the physical environment (e.g. temperature) or biological processes. Because of this, there is massive uncertainty about how the BCP will evolve over the coming decades and centuries as the climate changes. It is, however, certain that modification of the BCP will occur, and that this will feed back into the global climate system. Until we have a better understanding of the factors which determine the way the BCP functions at present, it will be impossible to predict how this will change in the future.
The student will use long-term time series data to investigate drivers and changes in the BCP of the North Atlantic. For nearly 30 years, with only a few gaps, time-series sediment traps have been deployed at 3000m depth at the Porcupine Abyssal Plain Observatory (PAP) to collect sedimenting material reflecting the strength and variability of the BCP. Over much of this period, biogeochemical variables such as chlorophyll, temperature and CO2 have been measured with high temporal resolution (a few hours) as indicators of the physical and biological environment driving the BCP (http://projects.noc.ac.uk/pap/). The aim of this PhD project is to uncover the factors responsible for the dramatic temporal variability in the BCP. To do so, the student will use data from the sediment traps, the PAP observatory sensors and other data such as from the Continuous Plankton Recorder and satellites. There will be opportunities to participate in research cruises during which additional material could be collected using a variety of different methods (e.g.The Marine Snow Catcher). Novel analysis of existing samples and those collected during research cruises will be carried out using, for instance, molecular techniques to provide additional insights into ecosystem drivers particularly in relation to microbial communities.
The SPITFIRE DTP programme provides comprehensive personal and professional development training alongside extensive opportunities for students to expand their multi-disciplinary outlook through interactions with a wide network of academic, research and industrial/policy partners. The student will be registered at the University of Southampton and hosted at the National Oceanography Centre. Methods to analyse existing and new data from the sediment trap programme and many other data sources will be an important part of the training. Specific training will include (1) chemical, microscopical and molecular analysis of existing and new material, (2) participation in research cruises on RRS Discovery or RRS James Cook to collect additional material using modern oceanographic and biogeochemical sampling techniques, (3) acquisition and analysis of data from satellite remote sensing, CPR and other open-source data bases, (4) large data analysis, (5) statistics and interpretation of time-series data.
Funding Notes
This SPITFIRE project is open to applicants who meet the SPITFIRE eligibility, alongside other exceptional applicants and will come with a fully funded studentship for UK students and EU students who meet the RCUK eligibility criteria.
To check your eligibility and find information on how to apply click
http://www.spitfire.ac.uk/how-apply
References
Giering, S. L., et al. (2014), Reconciliation of the carbon budget in the ocean's twilight zone, Nature, 307, 480–483, doi:10.1038/nature13123.
Frigstad, H., S. A. Henson, S. E. Hartman, A. M. Omar, E. Jeansson, H. Cole, C. Pebody, and R. S. Lampitt. (2015). Links between surface productivity and deep ocean particle flux at the Porcupine Abyssal Plain sustained observatory. Biogeosciences, 12, 5885-5897, https://doi.org/10.5194/bg-12-5885-2015
Lampitt, R.S., I.Salter, B.A.deCuevas, S.Hartman, K.E.Larkin, C.A.Pebody (2010). Long-term variability of downward particle flux in the deep northeast Atlantic: Causes and trends. Deep-Sea Research II 571346–1361