Circulation and oceanography of the Broughton Archipeligo
There are two main work components in this project; a program of field observations and a numerical modelling component. The observational program consists of quarterly water sampling surveys throughout the region and long-term deployments of recording instruments in key locations. The numerical modelling work is sub-divided into two parts, the refinement and validation of a barotropic (depth averaged) tidal model and the development and validation of a three-dimensional baroclinic circulation model of the region.
Currently, there are not many measurements of water properties in this region, and although some observations of currents and water levels have been collected, their short duration limits their usefulness. The field component of this proposal will add substantially to the data base of observations and increase our understanding of the circulation, and spatial and temporal variations of key water properties (e.g., dissolved oxygen) in this region. The long-term current velocity and water level data are essential for the refinement and validation of both the barotropic tidal model and the three-dimensional baroclinic model.
Water sampling stations have been strategically located throughout the region of interest in order to provide wide area coverage. Using a ship-board CTD/rosette system (Conductivity, Temperature and Depth) continuous profiles of temperature, salinity, dissolved oxygen, light transmission and fluorescence will be obtained as well as water samples at discrete depths for nutrients (nitrate plus nitrite, phosphate and silicate) and other chemical variables. The plan is to this conduct synoptic survey of the region four times per year for two years in order to resolve the annual cycle. To resolve the short time scale variations (hours to weeks) in dissolved oxygen we propose to purchase two internally recording dissolved oxygen instruments and maintain them for at least one year in key locations.
2002 - 2005
Pacific: Vancouver Island West Coast
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