OMEGA PROJECT. Objectives

Objectives

Three-dimensional ageostrophic circulation: to determine the three-dimensional ageostrophic circulation within an intense mesoscale upper ocean front (upper 300 m) and quantitatively estimate the vertical velocity.
1. To measure the short term three-dimensional spatial variability of the density field using quasi-synoptic sampling (CTD and SeaSoar) and to obtain the associated ageostrophic velocity distribution.
2. To determine the short term (order of 1 week) three-dimensional spatial and temporal variability of the density field and the associated ageostrophic velocity distribution using repeated sampling and data assimilation into a primitive equations (P.E.) numerical model.
3. To monitor the larger scale temporal variations in the current systems using the surface geostrophic velocity and hence the geoid along satellite tracks and also using prognostic P.E. computations.
4. To measure the three-dimensional ageostrophic flow using Lagrangian floats at different depths.
Vertical motion and bio-geochemical influences: to evaluate the impact of the ageostrophic vertical motion on the biogeochemical properties in the upper 200 m.
1. To investigate and assess the impact of mesoscale vertical motion on biogeochemical fluxes and biomass.
2. To improve our understanding of the relationship between remotely-sensed surface signatures (SST, surface height, SAR and ocean colour) and sub- surface structures in the water column.
3. To validate new optical satellite sensors to be launched between now and the scheduling of cruises related to this proposal.
New tool for routine computation of vertical velocity: to provide the scientific community with a new and useful tool for computation of vertical motions from routine CTD and ADCP data.

To analyse and integrate all the different estimates of the three-dimensional ageostrophic flow, with emphasis on the vertical velocity and net transport.
To establish a methodology for routine computation of vertical velocities from CTD and ADCP data.