Note: This position is linked to / funded by the EUR-OCEANS 'submesocale' Flagship awarded to UPMC and NOC after the June 2009 call.
Almost half of the global net primary production each year is attributed to oceanic phytoplankton. Organic material created through primary production can be sequestered deep in the ocean when it sinks, removing carbon dioxide from the atmosphere. This is the marine ‘biological pump’, a crucial component of the global carbon cycle.
Much work has been done in assessing the controls on this key process. In particular, in recent years it has become apparent that physical processes at the mesoscale (defined here as 10-100km) and submesoscale (1-10km), such as eddies, fronts and filaments, play a major role in driving primary production. This breakthrough was greatly aided by modelling studies which could examine processes at the necessary scales before observations could tackle them directly.
Although considerable attention is now being given to mesoscale and submesoscale variability in surface production little has been focussed on how such variability in the sinking flux of material is mediated from surface to sea floor. In particular, deep observations are still sparse and even more challenging to collect than in the surface. Accordingly the source of much of the variability seen in the few tantalising direct observations of the sinking flux is unknown, leaving large uncertainties in our global estimates of the size of the biological pump. One possibility is that a significant fraction of the variability may correspond to that seen in primary production at the mesoscale and submesoscale.
This project will investigate the conditions under which mesoscale and submesoscale variability in surface primary production can induce similar variability in the flux arriving at the benthos. It will embed a biological model into a high resolution physical simulation capable of reproducing mesoscale and submesoscale physical activity. By assessing the sensitivity of the sinking flux at depth to parameters controlling the rate of sinking and remineralisation, the influence of mesoscale and submesoscale surface physical phenomenon on the deep sequestration of organic material will be assessed.
The post is for 1 year, funded by the EUROceans Consortium, and the successful candidate will split their time between LOCEAN, Paris and the National Oceanography Centre, Southampton. Applications are encouraged from anyone with a suitably numerate PhD or equivalent in marine science. Modelling experience would be a significant advantage, particularly of high-resolution physical-biological simulations. The deadline for applications is 1st March 2010. Both informal enquiries and formal applications should be directed to either Dr Marina Levy of LOCEAN (email@example.com) or Dr Adrian Martin of NOCS (firstname.lastname@example.org).